[Skip to Navigation]
Sign In
Figure.  Studies Reporting Response to Treatment
Studies Reporting Response to Treatment

The size of the nodes corresponds to the number of patients. The thickness of the connecting lines corresponds to the number of studies. Techniques included open in situ decompression (OISD; 6 randomized clinical trials, 11 nonrandomized studies, 633 patients), subcutaneous transposition (SCT; 2 randomized clinical trials, 13 nonrandomized studies, 933 patients), submuscular transposition (SMT; 2 randomized clinical trials, 8 nonrandomized studies, 321 patients), endoscopic in situ decompression (EISD; 3 randomized clinical trials, 5 nonrandomized studies, 308 patients), open in situ decompression with medial epicondylectomy (OISD+E; 1 randomized clinical trial, 3 nonrandomized studies, 100 patients), endoscopic subcutaneous transposition (ESCT; 1 nonrandomized study, 52 patients), intramuscular transposition (IMT; 1 nonrandomized study, 9 patients), and speculum in situ decompression (SISD; 1 nonrandomized study, 15 patients).

Table 1.  League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Responding to Treatment (ie, Improving)a
League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Responding to Treatment (ie, Improving)a
Table 2.  League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Complicationsa
League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Complicationsa
Table 3.  League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Reoperation at the Same Surgical Site for Any Reasona
League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Reoperation at the Same Surgical Site for Any Reasona
Table 4.  League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Recurrent Cubital Tunnel Syndromea
League Table of Pairwise Comparisons in Network Meta-analysis for the Relative Risk (With 95% CIs) of Recurrent Cubital Tunnel Syndromea
Supplement.

eFigure 1. Study Selection Flowchart

eFigure 2. The Average Risk of Bias Contributions for Each Comparison

eFigure 3. Risk of Bias Summary for Randomized Studies

eFigure 4. Risk of Bias Summary for Nonrandomized Studies

eFigure 5. Design-Adjusted Analyses for Response to Treatment

eFigure 6. Forest Plots for Response to Treatment

eFigure 7. Network Plot of Randomized Studies Included in Analysis for Response to Treatment

eFigure 8. Network Plot of Nonrandomized Studies Included in Analysis for Response to Treatment

eFigure 9. Network Heat Plot for Response to Treatment

eFigure 10. Network Plot of Studies Included in the Analysis of Complications

eFigure 11. Network Heat Plot for Complications (Naive Random-Effects NMA)

eFigure 12. Network Heat Plot for Complications (Naive Fixed-Effects NMA)

eFigure 13. Network Plot of Studies Included in the Analysis of Reoperation

eFigure 14. Network Heat Plot for Reoperation (Naive Fixed-Effects Mantel-Haenszel NMA)

eFigure 15. Network Plot of Studies Included in the Analysis of Recurrence

eFigure 16. Network Heat Plot for Recurrence (Naive Random-Effects NMA)

eFigure 17. Network Heat Plot for Recurrence (Naive Fixed-Effects Mantel-Haenzel NMA)

eFigure 18. Comparison-Adjusted Funnel Plot

eTable 1. Summary of Study Characteristics

eTable 2. Summary of Variables That Might Moderate the Relative Effects of Treatments

eTable 3. Direct and Indirect Estimates From the Random-Effects NMA of Response to Treatment

eTable 4. Direct and Indirect Estimates From the Random-Effects NMA of Complications

eTable 5. League Table of Pairwise Comparisons for Complications (Fixed-Effects Mantel-Haenszel)

eTable 6. Direct and Indirect Estimates From the Fixed-Effects Mantel-Haenszel NMA of Complications

eTable 7. Comparisons of the Direct and Indirect Estimates From the Fixed-Effects NMA of Reoperation

eTable 8. Direct and Indirect Estimates From the Random-Effects NMA of Recurrence

eTable 9. League Table of Pairwise Comparisons for Recurrence (Fixed-Effects Mantel-Haenszel)

eTable 10. Direct and Indirect Estimates From the Fixed-Effects Mantel-Haenszel NMA of Recurrence

eTable 11. CINEMA Assessments for the Primary Outcome

eAppendix. Search Results

1.
An  TW, Evanoff  BA, Boyer  MI, Osei  DA.  The prevalence of cubital tunnel syndrome: a cross-sectional study in a US metropolitan cohort.   J Bone Joint Surg Am. 2017;99(5):408-416. doi:10.2106/JBJS.15.01162PubMedGoogle ScholarCrossref
2.
Hulkkonen  S, Lampainen  K, Auvinen  J, Miettunen  J, Karppinen  J, Ryhänen  J.  Incidence and operations of median, ulnar and radial entrapment neuropathies in Finland: a nationwide register study.   J Hand Surg Eur Vol. 2020;45(3):226-230. doi:10.1177/1753193419886741PubMedGoogle ScholarCrossref
3.
Basson  A, Olivier  B, Ellis  R, Coppieters  M, Stewart  A, Mudzi  W.  The effectiveness of neural mobilization for neuromusculoskeletal conditions: a systematic review and meta-analysis.   J Orthop Sports Phys Ther. 2017;47(9):593-615. doi:10.2519/jospt.2017.7117PubMedGoogle ScholarCrossref
4.
Apfel  E, Sigafoos  GT.  Comparison of range-of-motion constraints provided by splints used in the treatment of cubital tunnel syndrome—a pilot study.   J Hand Ther. 2006;19(4):384-391. doi:10.1197/j.jht.2006.07.028PubMedGoogle ScholarCrossref
5.
Svernlöv  B, Larsson  M, Rehn  K, Adolfsson  L.  Conservative treatment of the cubital tunnel syndrome.   J Hand Surg Eur Vol. 2009;34(2):201-207. doi:10.1177/1753193408098480PubMedGoogle ScholarCrossref
6.
NHS  Digital. Hospital admitted patient care activity, 2017-18. Published September 2018. Accessed December 2019. https://digital.nhs.uk
7.
Osei  DA, Groves  AP, Bommarito  K, Ray  WZ.  Cubital tunnel syndrome: incidence and demographics in a national administrative database.   Neurosurgery. 2017;80(3):417-420. doi:10.1093/neuros/nyw061PubMedGoogle ScholarCrossref
8.
Novak  CB, Mackinnon  SE.  Selection of operative procedures for cubital tunnel syndrome.   Hand (N Y). 2009;4(1):50-54. doi:10.1007/s11552-008-9133-zPubMedGoogle ScholarCrossref
9.
Adkinson  JM, Zhong  L, Aliu  O, Chung  KC.  Surgical treatment of cubital tunnel syndrome: trends and the influence of patient and surgeon characteristics.   J Hand Surg Am. 2015;40(9):1824-1831. doi:10.1016/j.jhsa.2015.05.009PubMedGoogle ScholarCrossref
10.
Byvaltsev  VA, Stepanov  IA, Kerimbayev  TT.  A systematic review and meta-analysis comparing open versus endoscopic in situ decompression for the treatment of cubital tunnel syndrome.   Acta Neurol Belg. 2019;120(1):1-8. doi:10.1007/s13760-019-01149-9PubMedGoogle ScholarCrossref
11.
O’Grady  EE, Vanat  Q, Power  DM, Tan  S.  A systematic review of medial epicondylectomy as a surgical treatment for cubital tunnel syndrome.   J Hand Surg Eur Vol. 2017;42(9):941-945. doi:10.1177/1753193417724351PubMedGoogle ScholarCrossref
12.
Mowlavi  A, Andrews  K, Lille  S, Verhulst  S, Zook  EG, Milner  S.  The management of cubital tunnel syndrome: a meta-analysis of clinical studies.   Plast Reconstr Surg. 2000;106(2):327-334. doi:10.1097/00006534-200008000-00014PubMedGoogle ScholarCrossref
13.
Caliandro  P, La Torre  G, Padua  R, Giannini  F, Padua  L.  Treatment for ulnar neuropathy at the elbow.   Cochrane Database Syst Rev. 2016;(11):CD006839. doi:10.1002/14651858.CD006839.pub4PubMedGoogle Scholar
14.
Liu  CH, Wu  SQ, Ke  XB,  et al.  Subcutaneous versus submuscular anterior transposition of the ulnar nerve for cubital tunnel syndrome: a systematic review and meta-analysis of randomized controlled trials and observational studies.   Medicine (Baltimore). 2015;94(29):e1207. doi:10.1097/MD.0000000000001207PubMedGoogle Scholar
15.
Zlowodzki  M, Chan  S, Bhandari  M, Kalliainen  L, Schubert  W.  Anterior transposition compared with simple decompression for treatment of cubital tunnel syndrome. A meta-analysis of randomized, controlled trials.   J Bone Joint Surg Am. 2007;89(12):2591-2598. doi:10.2106/JBJS.G.00183PubMedGoogle ScholarCrossref
16.
Chen  HW, Ou  S, Liu  GD,  et al.  Clinical efficacy of simple decompression versus anterior transposition of the ulnar nerve for the treatment of cubital tunnel syndrome: a meta-analysis.   Clin Neurol Neurosurg. 2014;126:150-155. doi:10.1016/j.clineuro.2014.08.005PubMedGoogle ScholarCrossref
17.
Smeraglia  F, Del Buono  A, Maffulli  N.  Endoscopic cubital tunnel release: a systematic review.   Br Med Bull. 2015;116(1):155-163. doi:10.1093/bmb/ldv049PubMedGoogle Scholar
18.
Buchanan  PJ, Chieng  LO, Hubbard  ZS, Law  TY, Chim  H.  Endoscopic versus open in situ cubital tunnel release: a systematic review of the literature and meta-analysis of 655 patients.   Plast Reconstr Surg. 2018;141(3):679-684. doi:10.1097/PRS.0000000000004112PubMedGoogle ScholarCrossref
19.
Toirac  A, Giugale  JM, Fowler  JR.  Open versus endoscopic cubital tunnel in situ decompression: a systematic review of outcomes and complications.   Hand (N Y). 2017;12(3):229-235. doi:10.1177/1558944716662018PubMedGoogle ScholarCrossref
20.
Ren  YM, Zhou  XH, Qiao  HY,  et al.  Open versus endoscopic in situ decompression in cubital tunnel syndrome: a systematic review and meta-analysis.   Int J Surg. 2016;35:104-110. doi:10.1016/j.ijsu.2016.09.012PubMedGoogle ScholarCrossref
21.
Shi  Q, MacDermid  JC, Santaguida  PL, Kyu  HH.  Predictors of surgical outcomes following anterior transposition of ulnar nerve for cubital tunnel syndrome: a systematic review.   J Hand Surg Am. 2011;36(12):1996-2001.e1, 6. doi:10.1016/j.jhsa.2011.09.024PubMedGoogle ScholarCrossref
22.
Macadam  SA, Gandhi  R, Bezuhly  M, Lefaivre  KA.  Simple decompression versus anterior subcutaneous and submuscular transposition of the ulnar nerve for cubital tunnel syndrome: a meta-analysis.   J Hand Surg Am. 2008;33(8):1314.e1-1314.e12. doi:10.1016/j.jhsa.2008.03.006PubMedGoogle ScholarCrossref
23.
Yahya  A, Malarkey  AR, Eschbaugh  RL, Bamberger  HB.  Trends in the surgical treatment for cubital tunnel syndrome: a survey of members of the American Society for Surgery of the Hand.   Hand (N Y). 2018;13(5):516-521. doi:10.1177/1558944717725377PubMedGoogle ScholarCrossref
24.
Carlton  A, Khalid  SI.  Surgical approaches and their outcomes in the treatment of cubital tunnel syndrome.   Front Surg. 2018;5(July):48. doi:10.3389/fsurg.2018.00048PubMedGoogle ScholarCrossref
25.
Kholinne  E, Alsharidah  MM, Almutair  O,  et al.  Revision surgery for refractory cubital tunnel syndrome: a systematic review.   Orthop Traumatol Surg Res. 2019;105(5):867-876. doi:10.1016/j.otsr.2019.03.020PubMedGoogle ScholarCrossref
26.
Salanti  G.  Indirect and mixed-treatment comparison, network, or multiple-treatments meta-analysis: many names, many benefits, many concerns for the next generation evidence synthesis tool.   Res Synth Methods. 2012;3(2):80-97. doi:10.1002/jrsm.1037PubMedGoogle ScholarCrossref
27.
Efthimiou  O, Debray  TPA, van Valkenhoef  G,  et al; GetReal Methods Review Group.  GetReal in network meta-analysis: a review of the methodology.   Res Synth Methods. 2016;7(3):236-263. doi:10.1002/jrsm.1195PubMedGoogle ScholarCrossref
28.
Salanti  G, Ades  AE, Ioannidis  JPA.  Graphical methods and numerical summaries for presenting results from multiple-treatment meta-analysis: an overview and tutorial.   J Clin Epidemiol. 2011;64(2):163-171. doi:10.1016/j.jclinepi.2010.03.016PubMedGoogle ScholarCrossref
29.
Higgins  JPT, Green  S, eds.  Cochrane Handbook for Systematic Reviews of Interventions, Version 5.1.0. Cochrane Collaboration; 2011.
30.
Moher  D, Liberati  A, Tetzlaff  J, Altman  DG; PRISMA Group.  Preferred Reporting Items for Systematic Reviews and Meta-analyses: the PRISMA statement.   Ann Intern Med. 2009;151(4):264-269, W64. doi:10.7326/0003-4819-151-4-200908180-00135PubMedGoogle ScholarCrossref
31.
Hutton  B, Salanti  G, Caldwell  DM,  et al.  The PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions: checklist and explanations.   Ann Intern Med. 2015;162(11):777-784. doi:10.7326/M14-2385PubMedGoogle ScholarCrossref
32.
Koziej  M, Trybus  M, Banach  M,  et al.  Comparison of patient-reported outcome measurements and objective measurements after cubital tunnel decompression.   Plast Reconstr Surg. 2018;141(5):1171-1181. doi:10.1097/PRS.0000000000004291PubMedGoogle ScholarCrossref
33.
Barry  MJ, Edgman-Levitan  S.  Shared decision making—pinnacle of patient-centered care.   N Engl J Med. 2012;366(9):780-781. doi:10.1056/NEJMp1109283PubMedGoogle ScholarCrossref
34.
Aagaard  T, Lund  H, Juhl  C.  Optimizing literature search in systematic reviews: are MEDLINE, EMBASE and CENTRAL enough for identifying effect studies within the area of musculoskeletal disorders?   BMC Med Res Methodol. 2016;16(1):161. doi:10.1186/s12874-016-0264-6PubMedGoogle ScholarCrossref
35.
Liu  C-H, Wu  S-Q, Ke  X-B,  et al.  Subcutaneous versus submuscular anterior transposition of the ulnar nerve for cubital tunnel syndrome: a systematic review and meta-analysis of randomized controlled trials and observational studies.   Medicine (Baltimore). 2015;94(29):e1207. doi:10.1097/MD.0000000000001207PubMedGoogle Scholar
36.
Capo  JT, Jacob  G, Maurer  RJ, Nourbakhsh  A, Preston  JS.  Subcutaneous anterior transposition versus decompression and medial epicondylectomy for the treatment of cubital tunnel syndrome.   Orthopedics. 2011;34(11):e713-e717. doi:10.3928/01477447-20110922-18PubMedGoogle Scholar
37.
Teo  MK, Trivedi  R, Waters  A.  The role of ulnar nerve transposition in ulnar entrapment neuropathy.   Br J Neurosurg. 2010;24(2):140. doi:10.3109/02688691003680382Google Scholar
38.
Izadpanah  A, Spinner  R, Kakar  S.  The efficacy of in-situ cubital tunnel release in management of elbow ulnar compression neuropathy in McGowan grade 3.   J Hand Surg Am. 2015;40(9). doi:10.1016/j.jhsa.2015.06.068Google Scholar
39.
Higgins  JP, Savović  J, Page  MJ, Sterne  JA.  Revised Cochrane Risk-of-Bias Tool for Randomized Trials (RoB2). Cochrane Library; 2016. doi:10.1002/14651858.CD201601
40.
Sterne  JA, Hernán  MA, Reeves  BC,  et al.  ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions.   BMJ. 2016;355:i4919. doi:10.1136/bmj.i4919PubMedGoogle ScholarCrossref
41.
Nikolakopoulou  A, Higgins  JPT, Papakonstantinou  T,  et al.  CINeMA: an approach for assessing confidence in the results of a network meta-analysis.   PLoS Med. 2020;17(4):e1003082. doi:10.1371/journal.pmed.1003082PubMedGoogle Scholar
42.
Rücker  G, Krahn  U, König  J, Efthimiou  O, Schwarzer  G. Netmeta: Network meta-analysis using frequentist methods. Published 2019. Accessed June 2019. https://github.com/guido-s/netmeta
43.
Efthimiou  O, Mavridis  D, Debray  TPA,  et al; GetReal Work Package 4.  Combining randomized and non-randomized evidence in network meta-analysis.   Stat Med. 2017;36(8):1210-1226. doi:10.1002/sim.7223PubMedGoogle ScholarCrossref
44.
Rücker  G, Schwarzer  G.  Ranking treatments in frequentist network meta-analysis works without resampling methods.   BMC Med Res Methodol. 2015;15(1):58. doi:10.1186/s12874-015-0060-8PubMedGoogle ScholarCrossref
45.
Higgins  JPT, Jackson  D, Barrett  JK, Lu  G, Ades  AE, White  IR.  Consistency and inconsistency in network meta-analysis: concepts and models for multi-arm studies.   Res Synth Methods. 2012;3(2):98-110. doi:10.1002/jrsm.1044PubMedGoogle ScholarCrossref
46.
König  J, Krahn  U, Binder  H.  Visualizing the flow of evidence in network meta-analysis and characterizing mixed treatment comparisons.   Stat Med. 2013;32(30):5414-5429. doi:10.1002/sim.6001PubMedGoogle ScholarCrossref
47.
Krahn  U, Binder  H, König  J.  A graphical tool for locating inconsistency in network meta-analyses.   BMC Med Res Methodol. 2013;13(1):35. doi:10.1186/1471-2288-13-35PubMedGoogle ScholarCrossref
48.
Chaimani  A, Higgins  JPT, Mavridis  D, Spyridonos  P, Salanti  G.  Graphical tools for network meta-analysis in STATA.   PLoS One. 2013;8(10):e76654. doi:10.1371/journal.pone.0076654PubMedGoogle Scholar
49.
Efthimiou  O, Rücker  G, Schwarzer  G, Higgins  JPT, Egger  M, Salanti  G.  Network meta-analysis of rare events using the Mantel-Haenszel method.   Stat Med. 2019;38(16):2992-3012. doi:10.1002/sim.8158PubMedGoogle ScholarCrossref
50.
Viechtbauer  W.  Conducting meta-analyses in R with the metafor package.   J Stat Softw. 2010;36(3). doi:10.18637/jss.v036.i03Google Scholar
51.
Wasserstein  RL, Lazar  NA.  The ASA statement on p-values: context, process, and purpose.   Am Stat. 2016;70(2):129-133. doi:10.1080/00031305.2016.1154108Google ScholarCrossref
52.
Amrhein  V, Greenland  S, McShane  B.  Scientists rise up against statistical significance.   Nature. 2019;567(7748):305-307. doi:10.1038/d41586-019-00857-9PubMedGoogle ScholarCrossref
53.
Efthimiou  O, White  IR.  The dark side of the force: multiplicity issues in network meta-analysis and how to address them.   Res Synth Methods. 2020;11(1):105-122. doi:10.1002/jrsm.1377PubMedGoogle ScholarCrossref
54.
Charles  YP, Coulet  B, Rouzaud  J-C, Daures  J-P, Chammas  M.  Comparative clinical outcomes of submuscular and subcutaneous transposition of the ulnar nerve for cubital tunnel syndrome.   J Hand Surg Am. 2009;34(5):866-874. doi:10.1016/j.jhsa.2009.01.008PubMedGoogle ScholarCrossref
55.
Dützmann  S, Martin  KD, Sobottka  S,  et al.  Open vs retractor-endoscopic in situ decompression of the ulnar nerve in cubital tunnel syndrome: a retrospective cohort study.   Neurosurgery. 2013;72(4):605-616. doi:10.1227/NEU.0b013e3182846dbdPubMedGoogle ScholarCrossref
56.
Gervasio  O, Gambardella  G, Zaccone  C, Branca  D.  Simple decompression versus anterior submuscular transposition of the ulnar nerve in severe cubital tunnel syndrome: a prospective randomized study.   Neurosurgery. 2005;56(1):108-117. doi:10.1227/01.NEU.0000145854.38234.81PubMedGoogle ScholarCrossref
57.
Geutjens  GG, Langstaff  RJ, Smith  NJ, Jefferson  D, Howell  CJ, Barton  NJ.  Medial epicondylectomy or ulnar-nerve transposition for ulnar neuropathy at the elbow?   J Bone Joint Surg Br. 1996;78(5):777-779. doi:10.1302/0301-620X.78B5.0780777PubMedGoogle ScholarCrossref
58.
Hahn  SB, Choi  YR, Kang  HJ, Kang  ES.  Decompression of the ulnar nerve and minimal medial epicondylectomy with a small incision for cubital tunnel syndrome: comparison with anterior subcutaneous transposition of the nerve.   J Plast Reconstr Aesthet Surg. 2010;63(7):1150-1155. doi:10.1016/j.bjps.2009.09.018PubMedGoogle ScholarCrossref
59.
Heikenfeld  R, Godolias  G.  Ulnar nerve decompression in cubital tunnel syndrome: open in situ decompression versus endoscopic decompression.   Arthrosc J Arthrosc Relat Surg. 2013;29(10):e98. doi:10.1016/j.arthro.2013.07.110Google Scholar
60.
Jaddue  DA, Saloo  SA, Sayed-Noor  AS.  Subcutaneous vs submuscular ulnar nerve transposition in moderate cubital tunnel syndrome.   Open Orthop J. 2009;3(1):78-82. doi:10.2174/1874325000903010078PubMedGoogle ScholarCrossref
61.
Kamat  AS, Jay  SM, Benoiton  LA, Correia  JA, Woon  K.  Comparative outcomes of ulnar nerve transposition versus neurolysis in patients with entrapment neuropathy at the cubital tunnel: a 20-year analysis.   Acta Neurochir (Wien). 2014;156(1):153-157. doi:10.1007/s00701-013-1962-zPubMedGoogle ScholarCrossref
62.
Keiner  D, Gaab  MR, Schroeder  HW, Oertel  J.  Comparison of the long-term results of anterior transposition of the ulnar nerve or simple decompression in the treatment of cubital tunnel syndrome—a prospective study.   Acta Neurochir (Wien). 2009;151(4):311-315. doi:10.1007/s00701-009-0218-4PubMedGoogle ScholarCrossref
63.
Köse  KÇ, Bilgin  S, Cebesoy  O,  et al.  Clinical results versus subjective improvement with anterior transposition in cubital tunnel syndrome.   Adv Ther. 2007;24(5):996-1005. doi:10.1007/BF02877704PubMedGoogle ScholarCrossref
64.
Krejčí  T, Večeřa  Z, Krejčí  O, Šalounová  D, Houdek  M, Lipina  R.  Comparing endoscopic and open decompression of the ulnar nerve in cubital tunnel syndrome: a prospective randomized study.   Acta Neurochir (Wien). 2018;160(10):2011-2017. doi:10.1007/s00701-018-3647-0PubMedGoogle ScholarCrossref
65.
Luo  S, Zhao  J, Su  W, Li  X.  Efficacy comparison between anterior subcutaneous and submuscular transposition of ulnar nerve to treat cubital tunnel syndrome.   Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010;24(5):577-580.PubMedGoogle Scholar
66.
Martin  K-D, Dützmann  S, Sobottka  SB,  et al.  Retractor-endoscopic nerve decompression in carpal and cubital tunnel syndromes: outcomes in a small series.   World Neurosurg. 2014;82(1-2):e361-e370. doi:10.1016/j.wneu.2013.09.026PubMedGoogle ScholarCrossref
67.
Mitsionis  GI, Manoudis  GN, Paschos  NK, Korompilias  AV, Beris  AE.  Comparative study of surgical treatment of ulnar nerve compression at the elbow.   J Shoulder Elbow Surg. 2010;19(4):513-519. doi:10.1016/j.jse.2009.10.014PubMedGoogle ScholarCrossref
68.
Schmidt  S, Kleist Welch-Guerra  W, Matthes  M, Baldauf  J, Schminke  U, Schroeder  HWS.  Endoscopic vs open decompression of the ulnar nerve in cubital tunnel syndrome: a prospective randomized double-blind study.   Neurosurgery. 2015;77(6):960-970. doi:10.1227/NEU.0000000000000981PubMedGoogle ScholarCrossref
69.
Stuffer  M, Jungwirth  W, Hussl  H, Schmutzhardt  E.  Subcutaneous or submuscular anterior transposition of the ulnar nerve?   J Hand Surg Br. 1992;17(3):248-250. doi:10.1016/0266-7681(92)90107-DPubMedGoogle ScholarCrossref
70.
Tong  J, Xu  B, Dong  Z, Zhang  C, Gu  Y.  Surgical outcome for severe cubital tunnel syndrome in patients aged >70 years: a mean follow-up of 4.5 years.   Acta Neurochir (Wien). 2017;159(5):917-923. doi:10.1007/s00701-017-3113-4PubMedGoogle ScholarCrossref
71.
Watts  AC, Bain  GI.  Patient-rated outcome of ulnar nerve decompression: a comparison of endoscopic and open in situ decompression.   J Hand Surg Am. 2009;34(8):1492-1498. doi:10.1016/j.jhsa.2009.05.014PubMedGoogle ScholarCrossref
72.
Zhang  D, Earp  BE, Blazar  P.  Rates of complications and secondary surgeries after in situ cubital tunnel release compared with ulnar nerve transposition: a retrospective review.   J Hand Surg Am. 2017;42(4):294.e1-294.e5. doi:10.1016/j.jhsa.2017.01.020PubMedGoogle ScholarCrossref
73.
Zhou  Y, Feng  F, Qu  X,  et al.  Effectiveness comparison between two different methods of anterior transposition of the ulnar nerve in treatment of cubital tunnel syndrome.   Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2012;26(4):429-432.PubMedGoogle Scholar
74.
Asamoto  S, Böker  D-K, Jödicke  A.  Surgical treatment for ulnar nerve entrapment at the elbow.   Neurol Med Chir (Tokyo). 2005;45(5):240-244. doi:10.2176/nmc.45.240PubMedGoogle ScholarCrossref
75.
Bacle  G, Marteau  E, Freslon  M,  et al.  Cubital tunnel syndrome: comparative results of a multicenter study of 4 surgical techniques with a mean follow-up of 92 months.   Orthop Traumatol Surg Res. 2014;100(4)(suppl):S205-S208. doi:10.1016/j.otsr.2014.03.009PubMedGoogle ScholarCrossref
76.
Baek  GH, Kwon  BC, Chung  MS.  Comparative study between minimal medial epicondylectomy and anterior subcutaneous transposition of the ulnar nerve for cubital tunnel syndrome.   J Shoulder Elbow Surg. 2006;15(5):609-613. doi:10.1016/j.jse.2005.10.007PubMedGoogle ScholarCrossref
77.
Bartels  RHMA, Verhagen  WIM, van der Wilt  GJ, Meulstee  J, van Rossum  LGM, Grotenhuis  JA.  Prospective randomized controlled study comparing simple decompression versus anterior subcutaneous transposition for idiopathic neuropathy of the ulnar nerve at the elbow: part 1.   Neurosurgery. 2005;56(3):522-530. doi:10.1227/01.NEU.0000154131.01167.03PubMedGoogle ScholarCrossref
78.
Biggs  M, Curtis  JA.  Randomized, prospective study comparing ulnar neurolysis in situ with submuscular transposition.   Neurosurgery. 2006;58(2):296-304. doi:10.1227/01.NEU.0000194847.04143.A1PubMedGoogle ScholarCrossref
79.
Bimmler  D, Meyer  VE.  Surgical treatment of the ulnar nerve entrapment neuropathy: submuscular anterior transposition or simple decompression of the ulnar nerve? long-term results in 79 cases.   Ann Chir Main Memb Super. 1996;15(3):148-157. doi:10.1016/S0753-9053%2896%2980005-6PubMedGoogle Scholar
80.
Bolster  MAJ, Zöphel  OT, van den Heuvel  ER, Ruettermann  M.  Cubital tunnel syndrome: a comparison of an endoscopic technique with a minimal invasive open technique.   J Hand Surg Eur Vol. 2014;39(6):621-625. doi:10.1177/1753193413498547PubMedGoogle ScholarCrossref
81.
Kazmers  NH, Lazaris  EL, Allen  CM, Presson  AP, Tyser  AR.  Comparison of surgical encounter direct costs for three methods of cubital tunnel decompression.   Plast Reconstr Surg. 2019;143(2):503-510. doi:10.1097/PRS.0000000000005196PubMedGoogle ScholarCrossref
82.
Malay  S, Chung  KC; SUN Study Group.  The minimal clinically important difference after simple decompression for ulnar neuropathy at the elbow.   J Hand Surg Am. 2013;38(4):652-659. doi:10.1016/j.jhsa.2013.01.022PubMedGoogle ScholarCrossref
83.
Kooner  S, Cinats  D, Kwong  C, Matthewson  G, Dhaliwal  G.  Conservative treatment of cubital tunnel syndrome: a systematic review.   Orthop Rev (Pavia). 2019;11(2):7955. doi:10.4081/or.2019.7955PubMedGoogle ScholarCrossref
84.
Smith  T, Nielsen  KD, Poulsgaard  L.  Ulnar neuropathy at the elbow: clinical and electrophysiological outcome of surgical and conservative treatment.   Scand J Plast Reconstr Surg Hand Surg. 2000;34(2):145-148. doi:10.1080/02844310050160006PubMedGoogle ScholarCrossref
85.
Wade  RG, Bland  JM, Wormald  JCR, Figus  A.  The importance of the unit of analysis: commentary on Beugels et al. (2016)—complications in unilateral versus bilateral deep inferior epigastric artery perforator flap breast reconstructions: a multicentre study.   J Plast Reconstr Aesthet Surg. 2016;69(9):1299-1300. doi:10.1016/j.bjps.2016.06.002PubMedGoogle ScholarCrossref
1 Comment for this article
EXPAND ALL
Ulnar "entrapment neuropathy" or "local neuropathy"?
Tapani Salmi, MD, PhD | Dept Clinical Neurophysiology, Helsinki University Hospital Finland
In numerous reports on ulnar nerve neuropathy at the cubital area, the non-dominant side is more frequent compared to the dominant side. This is very common in the clinical practice and demonstrates the importance of external (sudden and repeated) trauma to cause the local problem instead of the entrapment to be corrected using decompression type of surgery.

It would be interested to hear if the very simple factor, the site (dominant - nondominant) of the neuropathy is causing any difference to the current results of the surgery due to the different etiology of the neuropathy.
My hypothesis is
that in symptoms of the dominant site the surgery is required more often due to real compression and there should be some differences in the outcomes of surgery. The more common symptoms of the non-dominant site are caused by previous, often unrecognized external trauma (often occupational due to arm support of the chair etc), the elimination of the external compression is more important, and the outcomes of the surgery is not associated to the type of operation.
CONFLICT OF INTEREST: None Reported
READ MORE
Original Investigation
Surgery
November 24, 2020

Safety and Outcomes of Different Surgical Techniques for Cubital Tunnel Decompression: A Systematic Review and Network Meta-analysis

Author Affiliations
  • 1Department of Plastic and Reconstructive Surgery, Leeds Teaching Hospitals Trust, Leeds, United Kingdom
  • 2Leeds Institute for Medical Research, University of Leeds, Leeds, United Kingdom
  • 3Cancer Epidemiology Group, Institute of Cancer and Pathology and Institute of Data Analytics, University of Leeds, United Kingdom
  • 4Hull University Teaching Hospitals NHS Trust, Hull, United Kingdom
  • 5Bristol Institute of Clinical Neuroscience, Southmead Hospital, Bristol, United Kingdom
JAMA Netw Open. 2020;3(11):e2024352. doi:10.1001/jamanetworkopen.2020.24352
Key Points

Question  For adults with primary cubital tunnel syndrome, which operation is associated with the best chance of symptomatic cure and lowest risk of complications?

Findings  This network meta-analysis included 30 studies comparing 8 different operations in 2894 limbs. It found that 87% of patients improve with surgery and that open in situ decompression (with or without a medial epicondylectomy) was associated with the greatest response to treatment and lowest complication risk.

Meaning  The findings of this study suggest that for adults with primary cubital tunnel syndrome, the most beneficial operation appears to be open in situ decompression.

Abstract

Importance  Cubital tunnel syndrome is the second most common compressive neuropathy, affecting 6% of the population. Numerous different operations are performed globally to treat it; however, prior conventional (pairwise) meta-analyses have been unable to determine which procedure is associated with the best outcomes and fewest complications.

Objective  To evaluate which operation for cubital tunnel syndrome is associated with the greatest likelihood of symptomatic cure.

Data Sources  PubMed, EMBASE, and CENTRAL were searched from database inception to March 2, 2019, with no restrictions on the setting or design of studies.

Study Selection  Experimental and observational studies directly comparing the outcomes of at least 2 surgical treatments for adults with primary cubital tunnel syndrome were included. Case reports were excluded, and when comparative studies had subgroups with 1 participant, the single-participant subgroup was excluded. The treatments had to be in situ decompression with or without medial epicondylectomy or an anterior subcutaneous, subfascial, intramuscular, or submuscular transposition. The access could be open, minimally invasive, or endoscopic. The comparator could be sham surgery or any operation mentioned earlier.

Data Extraction and Synthesis  Data were extracted by 2 independent reviewers, following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline and the PRISMA Network Meta-analysis extension statement. Network meta-analysis was used to estimate the relative efficacy and safety associated with interventions using relative risks. Surgical techniques were ranked by their probability of being the best (P score) and interpreted in terms of their clinical impact.

Main Outcomes and Measures  The primary outcome was response to treatment (ie, symptomatic improvement). The secondary outcomes were perioperative complications, reoperation, and recurrence.

Results  A total of 30 studies of 2894 limbs undergoing 8 different operations were included. Across the studies, 56% of participants were men, the mean (SD) age was 48 (8) years, and patients had symptoms for a mean (SD) of 15 (7) months. Overall, 87% (95% CI, 92%-91%) of patients improved with surgery; all forms of in situ decompression were more effective than any type of transposition procedure; for example, open in situ decompression with epicondylectomy was associated with higher success rates than subcutaneous transposition (relative risk, 1.13; 95% CI, 1.01-1.25). Postoperatively, 3% (95% CI, 2%-4%) of patients developed complications, and in situ decompressions were ranked as the least risky, although there was considerable uncertainty in this outcome. Overall, 2% (95% CI, 1%-3%) of patients required reoperation; open in situ decompression was associated with the fewest reoperations; in comparison, submuscular transposition was associated with 5 times the risk of reoperation (relative risk, 5.08; 95% CI, 2.06-12.52). During surveillance, 3% (95% CI, 1%-4%) of patients developed recurrence, and open in situ decompression with epicondylectomy was ranked as the safest operation, although there was uncertainty in the estimates.

Conclusions and Relevance  In this network meta-analysis, open in situ decompression (with or without medial epicondylectomy) appeared to be the safest operation and also was associated with the best outcomes for patients with primary cubital tunnel syndrome. Future research should focus on better defining this disorder and developing core outcome measures.

Introduction

Cubital tunnel syndrome is the second most common compressive neuropathy, affecting up to 6% of the population1 or 36 per 100 000 person-years.2 Surgical decompression of the cubital tunnel is the most effective treatment.3-5 Consequently, approximately 15 000 people across the UK6 and US7 undergo surgical decompression annually.

There are numerous techniques for decompressing the ulnar nerve around the elbow, which include open, minimally invasive, and endoscopic approaches. Once the ulnar nerve is decompressed, to reduce traction on it in elbow flexion, resection of the medial epicondyle (epicondylectomy) may be performed, with or without anterior transposition of the ulnar nerve to a subcutaneous, subfascial, or submuscular position. Several factors inform surgeons’ choice of technique,8 and there are no clear indications for 1 approach over another. Therefore, most surgeons (86%) use more than 1 procedure in their treatment of patients with cubital tunnel syndrome.9 During the last decade, at least 15 systematic reviews and pairwise meta-analyses have failed to resolve uncertainty about the efficacy and safety of these different operations for primary cubital tunnel syndrome,10-22 which is manifested in persistent variation in practice.23 This uncertainty is important to resolve because as many as 30% of patients do not improve after surgery24 and many are subject to revision surgery, which is rarely curative.25

Network meta-analysis is a technique for comparing multiple treatments simultaneously by combining direct evidence from clinical studies and indirect evidence from within a network. This advanced form of meta-analysis has several distinct advantages over standard (pairwise) meta-analyses, including better precision and power,26,27 the ability to compare interventions that have not been directly compared before (ie, in a real-life head-to-head study), and the capacity to rank competing treatments to inform clinical decisions.28 Therefore, network meta-analysis has the potential to address some of the remaining uncertainties about the efficacy and safety associated with different operations for cubital tunnel syndrome. In this study, we aimed to rank the safety and outcomes of different techniques for adults with primary cubital tunnel decompression.

Methods

This review was registered on the PROSPERO database (CRD42019127892); it was designed and conducted in accordance with the Cochrane Handbook for Systematic Reviews of Interventions, version 5.1.029 and was written in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guideline30 and the PRISMA Network Meta-analysis extension statement.31

Study Selection

We included experimental and observational studies directly comparing the outcomes of at least 2 surgical treatments for adults (aged >16 years) with primary cubital tunnel syndrome. We excluded case reports, and when comparative studies had a subgroup with 1 participant, the single-participant subgroup was excluded. The intervention had to be 1 of the following open, minimally invasive, or endoscopic techniques: in situ decompression; in situ decompression with medial epicondylectomy; anterior subcutaneous, anterior subfascial, intramuscular, or submuscular transposition; or any combination thereof. The comparator could be sham surgery or any of the earlier mentioned techniques.

Outcomes

The primary outcome was response to treatment. In the absence of a core outcome set, symptomatic improvement was measured with a variety of well-known tools, such as the McGowan, Bishop, Dellon, Yasutaka, and Wilson-Krout classifications. All tools assess similar parameters and broadly agree in cubital tunnel syndrome.32 They cannot be approximated to a scale, but changes after surgery (for better or worse) can be dichotomized into responders and nonresponders. We used the outcome measures in the original study to classify patients as responders or nonresponders. For example, if a patient’s McGowan score improved after surgery, they were classified as a responder. Conversely, if a patient’s McGowan score did not change or worsened after surgery, then they were defined as a nonresponder (treatment failure). When multiple outcome measures were reported, the patient-reported assessment was used because this is the most meaningful approach for patients.33 There was no minimum or maximum severity (clinical or electrodiagnostic) required for inclusion.

The secondary outcomes included short-term surgical site complications that warranted any form of medical or surgical intervention, including bleeding, infection, and wound dehiscence. Numbness around the surgical site was not considered a complication unless it was caused by the division of a named cutaneous nerve and treated by microsurgical neurorrhaphy. Reoperation was defined as repeated surgery for any reason (eg, evacuation of a hematoma, debridement of an infected or necrotic wound, revisional surgery for recurrence) and recurrence of symptoms (as defined by the original study) after a period of symptomatic relief, whether or not additional treatment was required.

Search Strategy

PubMed, EMBASE, and CENTRAL were interrogated34 according to the search strategy in the eAppendix in the Supplement. No language restrictions were applied. Our searches yielded 1827 results in PubMed, 1508 in EMBASE, and 79 in CENTRAL on March 2, 2019. After deduplication, there were 522 citations, which were independently screened by 3 review authors (R.G.W., T.T.G., and R.F.). The full texts of all potentially relevant articles were obtained. The reference lists for included articles and previous systematic reviews10,11,17-21,35 were also reviewed. Included articles were compared and disagreements resolved by discussion.

Nodes

Treatments were grouped into the following nodes: open in situ decompression, open in situ decompression and medial epicondylectomy, subcutaneous transposition, submuscular transposition, endoscopic in situ decompression, endoscopic subcutaneous transposition, intramuscular transposition, and speculum in situ decompression. One study36 reported a subfascial transposition, but the described surgical technique was identical to an anterior subcutaneous transposition and so data were assimilated in the subcutaneous transposition node.

Data Extraction

Three review authors (R.G.W., T.T.G., and R.F.) extracted details of the study design, demographic characteristics, and statistics of interest. Where data were missing or unclear, the author(s) were contacted. The authors of 1 article37 provided data on request. In 1 study,36 2 groups with single participants were discarded. In 1 study,38 we were unable to disaggregate the outcomes for intramuscular transposition and submuscular transposition, requiring the exclusion of these groups. The unit of analysis was the unit reported in the study; bilateral procedures are rarely performed simultaneously, so we considered that bilateral procedures (if not otherwise stated) were performed at times sufficiently separated to be considered independent.

Risk of Bias Assessment

The risk of methodological bias was assessed by 3 authors (R.G.W., T.T.G., and R.F.) independently, using the Cochrane Risk of Bias tool39 (for randomized trials) or ROBINS-I tool40 (for observational studies). Assessments were displayed graphically with RevMan version 5 (Cochrane Collaboration) and the Confidence in Network Meta-Analysis41 tool. Disagreements were resolved by discussion.

Assessing the Transitivity Assumption in Network Meta-analysis

An important concept of network meta-analysis is that all patients in a network should be equally eligible (in principle) to receive any of the treatments, a phenomenon that is typically termed jointly randomizable. This means that all patients in our networks should in principle be eligible to undergo any of the decompressive operations described. We assessed the validity of the transitivity assumption underlying the network meta-analysis conceptually by considering whether participants in the identified studies were jointly randomizable (ie, could in principle receive any of the treatments in the network) and whether the distribution of effect modifiers was similar across nodes.27 In this case, an effect modifier is a factor that changes the effectiveness of surgery. For example, it is noted that older patients benefit less from decompressive surgery than younger patients; therefore, age might modify the effectiveness of surgery. We tested the distribution of commonly espoused effect modifiers (ie, age, sex, and symptom severity) to ensure that they were balanced and thus our estimates were not confounded.

Statistical Analysis

We produced a network plot to summarize the treatments followed by a series of frequentist, random-effects, network meta-analyses, using the netmeta package in R version 3 (R Project for Statistical Computing)42 and assuming a single heterogeneity parameter. To assess the agreement between randomized and nonrandomized evidence, we first performed separate network meta-analyses and compared the results.43 Because no important discrepancies were observed, we performed a joint analysis that included both study types (so-called naive network meta-analysis). Interventions were ranked by their P scores44 with the netrank function; P scores are assumed to take a value between 0 and 1, with a higher score indicating a better treatment.44 With the netleague package, network meta-analysis results are summarized in league tables and treatments ordered by their P score. Forest plots of relative risks and 95% CIs were generated with open in situ decompression as the reference treatment. Heterogeneity was quantified through the standard deviation of random effects (τ, assumed common for all comparisons in the network). Inconsistency was assessed with both global and local methods with the netsplit package45,46 and displayed via heat plots45,47 with the netheat command. We produced forest plots to show the relative risk and 95% CIs for the outcomes of interest, with open in situ decompression as the reference operation. To assess possible small study effects for the primary outcome, we produced a comparison adjusted funnel plot48 in Stata version 15 (StataCorp)48 with the netfunnel package.

Next, we performed a series of designed-adjusted analyses,43 whereby data from randomized studies were combined with data from nonrandomized studies after down-weighting of the effect of the latter. These analyses involved a variance-inflation factor43 (ie, an extra parameter used to increase the variance of nonrandomized studies), thus reducing their effect on the pooled network meta-analysis estimate. We used the following variance inflation factors: w= 1 (corresponding to the naive network meta-analysis [ie, including all studies at face value]), 0.8, 0.6, 0.4, 0.2, and 0 [ie, 0 excluded nonrandomized studies from the analysis]). Randomized clinical trials were not down-weighted in these designed-adjusted analyses. We produced forest plots with the results of all treatments vs the reference (open in situ decompression) for all analyses to show how gradually allowing nonrandomized evidence to inform the estimates of relative treatment effects. In our designed-adjusted analyses, we did not adjust the point estimates from nonrandomized studies43 because we could not be confident of the direction and magnitude of potential bias in the treatment effects.

Given that the secondary outcomes were rare, we used sensitivity fixed-effects Mantel-Haenszel network meta-analyses49 (using the netmetabin package), which synthesize odds ratios; however, for rare events, odds and risks are almost identical. Inconsistency in these networks was assessed with the netsplit package and SIDDE approach.49 The RStudio version 1.3 (R Project for Statistical Computing) package metaprop50 was used to estimate the pooled prevalence of outcomes, using Hartung-Knapp-Sidik-Jonkman random effects and the Freeman-Tukey double arcsine transformation to stabilize the variances of proportions close to 0 or 1.

Recent publications have highlighted problems with null hypothesis testing,51,52 particularly in network meta-analysis.53 Therefore, we did not use the concept of statistical significance when presenting or discussing results from network meta-analyses but instead focused on the clinical interpretation in relation to the corresponding point estimates and their respective confidence intervals.

Results
Study Selection

After review of 68 full texts, 38 articles were excluded with reasons (eFigure 1 in the Supplement), and 30 studies36-38,54-80 describing 8 operations were included.

Study Characteristics

eTable 1 in the Supplement shows that there were 2894 limbs (belonging to ≥ 2675 patients) derived from 6 randomized trials,56,57,59,64,68,77 1 quasi-randomized clinical trial,78 3 prospective cohort studies,60,62,71 14 retrospective cohort studies,36-38,54,55,58,61,63,66,67,70,72,74,75 and 6 studies that did not describe the design.65,69,73,76,79,80 Across the included studies, 56% were men, the mean (SD) age was 48 (8) years, and patients had symptoms for a mean (SD) of 15 (7) months.

Risk of Bias Within Studies

The average risk of bias contributions for each comparison within the network are shown in eFigure 2 in the Supplement. The assessments of the risk of methodological bias for randomized clinical trials and nonrandomized studies are shown in eFigure 3 and eFigure 4 in the Supplement, respectively.

Assessment of Transitivity

After grouping the studies by treatment comparison and inspecting the distribution of possible effect modifiers, there were no significant differences between the demographic characteristics or preoperative McGowan grades for all treatments (eTable 2 in the Supplement). Therefore, they were judged to be sufficiently similar to be jointly synthesized in a network meta-analysis.

Agreement Between Randomized and Nonrandomized Studies

eFigure 5 and eFigure 6 in the Supplement show how the estimates derived from a network meta-analysis of only randomized controlled trials compare with a network meta-analysis of nonrandomized studies. The graphs showed no discrepancies between randomized and nonrandomized evidence. This was further corroborated after testing for differences between the 2 estimates for each treatment comparison (P > .05 for all χ2 tests). Thus, there was no evidence of incompatibility between randomized and nonrandomized evidence, so we proceeded with a joint (ie, naive) analysis. The randomized and nonrandomized studies contributing to the analyses are disaggregated in eFigure 7 and eFigure 8 in the Supplement.

Response to Treatment

The network was composed of 30 studies,36-38,54-80 with 37 direct comparisons of 8 surgical techniques (Figure). Subcutaneous transposition was the most common operation (n = 1101 [38%]), followed by open in situ decompression (n = 803 [28%]), submuscular transposition (n = 397 [14%]), and endoscopic in situ decompression (n = 361 [12%]), with the remaining limbs treated by other techniques. Overall, 87% of patients improved with surgery (95% CI, 82%-91%; I2, 85%), and in situ decompressions (whether performed by an open, endoscopic, or minimally invasive approach) were superior to any type of transposition. Specifically, open in situ decompression and medial epicondylectomy was ranked as the best technique (P score, 0.8787), with a 13% (95% CI, 1%-25%) higher chance of cure than with subcutaneous transposition. Detailed results for all treatment comparisons are shown in Table 1. The estimated heterogeneity of the network was small (τ2 = 0.003); however, the local (ie, back-calculation) method identified inconsistency between the direct and indirect evidence for open in situ decompression and subcutaneous transposition (eFigure 9 and eTable 3 in the Supplement).

Surgical Site Complications

The network was composed of 25 studies36,55-63,65,67,69-75,77-79 with 22 direct comparisons of complications after 6 different operations (eFigure 10 in the Supplement). Overall, 3% of patients developed a postoperative complication (95% CI, 2%-4%; I2, 55%). Endoscopic in situ decompression was ranked as the most hazardous operation (ie, most likely to result in complications), whereas open in situ decompression and medial epicondylectomy was the least. Detailed results are shown in Table 2. There was no measurable heterogeneity (τ2 = 0) (eTable 4 in the Supplement) or inconsistency within the network (eFigure 11 in the Supplement).

A sensitivity fixed-effects Mantel-Haenszel network meta-analysis yielded similar findings (eTable 5 in the Supplement) and again showed that open in situ decompression was associated with fewer complications than transposition and endoscopic or minimally invasive procedures. There was still no measurable heterogeneity (τ2 = 0) (eTable 6 in the Supplement) or inconsistency within the network (eFigure 12 in the Supplement).

Reoperation

Reoperation was reported in 17 studies38,55,56,61-66,68,70-72,75,77-79; however, because of the rate of zero-event groups and the overall rarity of reoperation, only 7 studies38,55,68,72,75,77,78 could be synthesized in a fixed-effects Mantel-Haenszel network meta-analysis of 5 different treatments, with 15 direct comparisons (eFigure 13 in the Supplement). During follow-up, 2% of patients required revision surgery (95% CI, 1%-3%; I2, 61%). With 95% probability, submuscular transposition was the most hazardous technique, with 5 times the risk of reoperation compared with open in situ decompression (relative risk, 5.08; 95% CI, 2.06-12.52). Detailed comparisons of treatments are provided in Table 3. There was no measurable heterogeneity (τ2 = 0) (eTable 7 in the Supplement) or inconsistency within the network (eFigure 14 in the Supplement).

Recurrence

Overall, 15 studies36,38,55,56,63-68,72,75,77-79 reported recurrence, providing 19 direct comparisons of 8 operations (eFigure 15 in the Supplement). During surveillance, 3% of patients developed recurrent symptoms (95% CI, 1%-4%; I2, 66%). Open in situ decompression and medial epicondylectomy was ranked as the best technique with the lowest risk of recurrence. Conversely, and with 78% probability, submuscular transposition was the most hazardous operation and was associated with the highest risk of recurrence (Table 4). There was no measurable heterogeneity (τ2 = 0.93) (eTable 8 in the Supplement) or inconsistency within the network (eFigure 16 in the Supplement).

A sensitivity fixed-effects Mantel-Haenszel network meta-analysis yielded similar findings (eTable 9 in the Supplement). There was still no measurable heterogeneity (τ2 = 0) (eTable 10 in the Supplement) or inconsistency within the network (eFigure 17 in the Supplement).

Small-Study Effects

An adjusted funnel plot showed no evidence of small-study effects. eFigure 18 in the Supplement presents the details.

Assessing Confidence in Results From the Analyses

There was moderate confidence in the mixed evidence but low confidence in the indirect evidence. eTable 11 in the Supplement presents the details.

Discussion

This systematic review and network meta-analysis found that open in situ decompression with or without medial epicondylectomy was associated with the greatest response to treatment and the lowest risk of complications, reoperation, and recurrence. Our network meta-analysis provides a central reference point for the global evidence on cubital tunnel syndrome surgery to help inform clinician practice, training, and international guidelines.

Our findings show that in situ decompression (whether by open, endoscopic, or minimally invasive means) was associated with lower risk of complications than any form of transposition procedure for primary cubital tunnel syndrome (Table 2); furthermore, the addition of an epicondylectomy was associated with an increased probability of symptomatic cure without increasing the risks of complications. The 95% CIs around these estimates are narrow, indicating a high degree of certainty, which is corroborated by the sensitivity analysis. Clearly, selecting an operation with the highest success rate and lowest complication risk is beneficial to patients. The reduced operative time and complexity of in situ decompression77,81 are also beneficial to surgeons. Furthermore, health care services stand to gain from our findings because in situ decompressions are 18% to 55% less expensive than transposition procedures,81 a relative cost saving that does not include the direct and indirect savings that come from avoiding complications, reoperation, and recurrence, which are more common in transposition surgeries. Whether the addition of an epicondylectomy to an in situ decompression increases the direct cost is unclear and needs exploring. However, it is plausible that any increase in surgical time and cost may be offset by a lower risk of complications and reoperation. Overall, the results suggest that in situ decompression (with or without a medial epicondylectomy) is the most effective and safe operation for primary cubital tunnel syndrome.

This review has identified important deficiencies in the literature. First, stakeholders must reach consensus on the definition of cubital tunnel syndrome, with or without classification-system-based patient-reported outcomes measures that have constructive validity. Second, a set of core outcome measures is needed to complement work on the minimal clinical important differences in ulnar neuropathy.82 Thereafter, we echo calls13,83 for comparative studies of operative vs nonoperative treatments. There is a paucity of data on nonoperative management,84 and we have a responsibility to inform patients about the evidence for and against all management options.

Limitations

This study has limitations. The surveillance period used in most studies is arguably insufficient to capture all cases of reoperation and recurrence because relapse typically occurs between 6 and 21 months postoperatively.25 Therefore, our estimates may underestimate the true prevalence of recurrence, which, compounded by biases of attrition and reporting, may misrepresent the true risk of recurrence for a given procedure. As such, we recommend cautious interpretation of these outcomes.

Ideally, the analyses of response to treatment would have included nonoperative treatments, although this might violate transitivity assumptions, given that some surgeons may not accept or offer nonoperative treatment to patients with moderate or severe cubital tunnel syndrome.

Bilateral surgery was described in 6 studies,57,66,68,70,74,75 which raises concerns about the unit of analysis85 and makes it impossible to judge how this may have affected our network meta-analyses. Despite this, it is likely that bilateral operations were performed at times sufficiently separated to be considered independent events, and all studies that reported bilateral operations used the same procedure on both limbs.

We transformed binomial data (to pool) with the Freeman-Tukey method because it stabilizes the variances of proportions close to 0 or 1; however, this method can yield unreliable estimates when back-transformed. Similarly, we used the DerSimonian-Laird method to synthesize binomial data, and this can induce biased estimates with falsely high precision; better methods exist but are not yet available. Therefore, caution is recommended when the pooled prevalence of outcomes is interpreted.

Conclusions

Overall, the results of this study suggest that the rate of cure for patients with cubital tunnel syndrome who receive surgery is high and complications are uncommon. According to the available evidence and notwithstanding some uncertainty regarding the estimates, open in situ decompression (with or without medial epicondylectomy) appeared to be the best procedure for patients with primary cubital tunnel syndrome. We suggest that future research focus on defining the disorder and generating core outcome measures before further (necessary) comparative studies are undertaken.

Back to top
Article Information

Accepted for Publication: September 7, 2020.

Published: November 24, 2020. doi:10.1001/jamanetworkopen.2020.24352

Open Access: This is an open access article distributed under the terms of the CC-BY License. © 2020 Wade RG et al. JAMA Network Open.

Corresponding Author: Ryckie G. Wade, MBBS, MSc, MClinEd, Academic Plastic Surgery Office, Department of Plastic and Reconstructive Surgery, Leeds General Infirmary, Leeds Teaching Hospitals, Leeds LS1 3EX, United Kingdom (ryckiewade@gmail.com).

Author Contributions: Mr Wade and Ms Bourke had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis.

Concept and design: Wade, Burr, Teo.

Acquisition, analysis, or interpretation of data: All authors.

Drafting of the manuscript: Wade, Griffiths, Flather.

Critical revision of the manuscript for important intellectual content: Wade, Flather, Burr, Teo, Bourke.

Statistical analysis: Wade, Burr.

Obtained funding: Wade.

Administrative, technical, or material support: Wade, Griffiths, Flather.

Supervision: Wade, Teo, Bourke.

Conflict of Interest Disclosures: Mr Wade reported receiving grants from the National Institute for Health Research (NIHR) during the conduct of the study and from NIHR outside the submitted work. Dr Burr reported receiving personal fees from Takeda and AbbVie outside the submitted work. No other disclosures were reported.

Funding/Support: Mr Wade is a doctoral research fellow funded by the NIHR (DRF-2018-11-ST2-028).

Role of the Funder/Sponsor: The NIHR had no direct role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

Disclaimer: The views expressed are those of the author(s) and not necessarily those of the United Kingdom’s National Health Service, NIHR, or Department of Health.

Additional Contributions: We thank Hebatullah M. Abdulazeem, PGDip (Technische Universität München), and Shenxing Du (Dongyang People’s Hospital/The Affiliated Dongyang Hospital of Wenzhou Medical University) for translating articles originally written in German and Chinese, respectively. We thank Orestis Efthimiou, PhD (Institute of Social and Preventive Medicine, University of Bern), for providing the basis of the regimens in R for combining randomized and nonrandomized evidence. We thank Alexis Dinno, ScD, MPH, MEM (Portland State University), for her advice on the ideal method of adjustment for multiplicity when assessing our transitivity assumptions, using her dunntest package within Stata. No one received financial compensation for their contributions.

Additional Information: The raw extracted data are available via the Open Science Framework at https://osf.io/8kyw7/. The statistical syntax is available from Mr Wade on request.

References
1.
An  TW, Evanoff  BA, Boyer  MI, Osei  DA.  The prevalence of cubital tunnel syndrome: a cross-sectional study in a US metropolitan cohort.   J Bone Joint Surg Am. 2017;99(5):408-416. doi:10.2106/JBJS.15.01162PubMedGoogle ScholarCrossref
2.
Hulkkonen  S, Lampainen  K, Auvinen  J, Miettunen  J, Karppinen  J, Ryhänen  J.  Incidence and operations of median, ulnar and radial entrapment neuropathies in Finland: a nationwide register study.   J Hand Surg Eur Vol. 2020;45(3):226-230. doi:10.1177/1753193419886741PubMedGoogle ScholarCrossref
3.
Basson  A, Olivier  B, Ellis  R, Coppieters  M, Stewart  A, Mudzi  W.  The effectiveness of neural mobilization for neuromusculoskeletal conditions: a systematic review and meta-analysis.   J Orthop Sports Phys Ther. 2017;47(9):593-615. doi:10.2519/jospt.2017.7117PubMedGoogle ScholarCrossref
4.
Apfel  E, Sigafoos  GT.  Comparison of range-of-motion constraints provided by splints used in the treatment of cubital tunnel syndrome—a pilot study.   J Hand Ther. 2006;19(4):384-391. doi:10.1197/j.jht.2006.07.028PubMedGoogle ScholarCrossref
5.
Svernlöv  B, Larsson  M, Rehn  K, Adolfsson  L.  Conservative treatment of the cubital tunnel syndrome.   J Hand Surg Eur Vol. 2009;34(2):201-207. doi:10.1177/1753193408098480PubMedGoogle ScholarCrossref
6.
NHS  Digital. Hospital admitted patient care activity, 2017-18. Published September 2018. Accessed December 2019. https://digital.nhs.uk
7.
Osei  DA, Groves  AP, Bommarito  K, Ray  WZ.  Cubital tunnel syndrome: incidence and demographics in a national administrative database.   Neurosurgery. 2017;80(3):417-420. doi:10.1093/neuros/nyw061PubMedGoogle ScholarCrossref
8.
Novak  CB, Mackinnon  SE.  Selection of operative procedures for cubital tunnel syndrome.   Hand (N Y). 2009;4(1):50-54. doi:10.1007/s11552-008-9133-zPubMedGoogle ScholarCrossref
9.
Adkinson  JM, Zhong  L, Aliu  O, Chung  KC.  Surgical treatment of cubital tunnel syndrome: trends and the influence of patient and surgeon characteristics.   J Hand Surg Am. 2015;40(9):1824-1831. doi:10.1016/j.jhsa.2015.05.009PubMedGoogle ScholarCrossref
10.
Byvaltsev  VA, Stepanov  IA, Kerimbayev  TT.  A systematic review and meta-analysis comparing open versus endoscopic in situ decompression for the treatment of cubital tunnel syndrome.   Acta Neurol Belg. 2019;120(1):1-8. doi:10.1007/s13760-019-01149-9PubMedGoogle ScholarCrossref
11.
O’Grady  EE, Vanat  Q, Power  DM, Tan  S.  A systematic review of medial epicondylectomy as a surgical treatment for cubital tunnel syndrome.   J Hand Surg Eur Vol. 2017;42(9):941-945. doi:10.1177/1753193417724351PubMedGoogle ScholarCrossref
12.
Mowlavi  A, Andrews  K, Lille  S, Verhulst  S, Zook  EG, Milner  S.  The management of cubital tunnel syndrome: a meta-analysis of clinical studies.   Plast Reconstr Surg. 2000;106(2):327-334. doi:10.1097/00006534-200008000-00014PubMedGoogle ScholarCrossref
13.
Caliandro  P, La Torre  G, Padua  R, Giannini  F, Padua  L.  Treatment for ulnar neuropathy at the elbow.   Cochrane Database Syst Rev. 2016;(11):CD006839. doi:10.1002/14651858.CD006839.pub4PubMedGoogle Scholar
14.
Liu  CH, Wu  SQ, Ke  XB,  et al.  Subcutaneous versus submuscular anterior transposition of the ulnar nerve for cubital tunnel syndrome: a systematic review and meta-analysis of randomized controlled trials and observational studies.   Medicine (Baltimore). 2015;94(29):e1207. doi:10.1097/MD.0000000000001207PubMedGoogle Scholar
15.
Zlowodzki  M, Chan  S, Bhandari  M, Kalliainen  L, Schubert  W.  Anterior transposition compared with simple decompression for treatment of cubital tunnel syndrome. A meta-analysis of randomized, controlled trials.   J Bone Joint Surg Am. 2007;89(12):2591-2598. doi:10.2106/JBJS.G.00183PubMedGoogle ScholarCrossref
16.
Chen  HW, Ou  S, Liu  GD,  et al.  Clinical efficacy of simple decompression versus anterior transposition of the ulnar nerve for the treatment of cubital tunnel syndrome: a meta-analysis.   Clin Neurol Neurosurg. 2014;126:150-155. doi:10.1016/j.clineuro.2014.08.005PubMedGoogle ScholarCrossref
17.
Smeraglia  F, Del Buono  A, Maffulli  N.  Endoscopic cubital tunnel release: a systematic review.   Br Med Bull. 2015;116(1):155-163. doi:10.1093/bmb/ldv049PubMedGoogle Scholar
18.
Buchanan  PJ, Chieng  LO, Hubbard  ZS, Law  TY, Chim  H.  Endoscopic versus open in situ cubital tunnel release: a systematic review of the literature and meta-analysis of 655 patients.   Plast Reconstr Surg. 2018;141(3):679-684. doi:10.1097/PRS.0000000000004112PubMedGoogle ScholarCrossref
19.
Toirac  A, Giugale  JM, Fowler  JR.  Open versus endoscopic cubital tunnel in situ decompression: a systematic review of outcomes and complications.   Hand (N Y). 2017;12(3):229-235. doi:10.1177/1558944716662018PubMedGoogle ScholarCrossref
20.
Ren  YM, Zhou  XH, Qiao  HY,  et al.  Open versus endoscopic in situ decompression in cubital tunnel syndrome: a systematic review and meta-analysis.   Int J Surg. 2016;35:104-110. doi:10.1016/j.ijsu.2016.09.012PubMedGoogle ScholarCrossref
21.
Shi  Q, MacDermid  JC, Santaguida  PL, Kyu  HH.  Predictors of surgical outcomes following anterior transposition of ulnar nerve for cubital tunnel syndrome: a systematic review.   J Hand Surg Am. 2011;36(12):1996-2001.e1, 6. doi:10.1016/j.jhsa.2011.09.024PubMedGoogle ScholarCrossref
22.
Macadam  SA, Gandhi  R, Bezuhly  M, Lefaivre  KA.  Simple decompression versus anterior subcutaneous and submuscular transposition of the ulnar nerve for cubital tunnel syndrome: a meta-analysis.   J Hand Surg Am. 2008;33(8):1314.e1-1314.e12. doi:10.1016/j.jhsa.2008.03.006PubMedGoogle ScholarCrossref
23.
Yahya  A, Malarkey  AR, Eschbaugh  RL, Bamberger  HB.  Trends in the surgical treatment for cubital tunnel syndrome: a survey of members of the American Society for Surgery of the Hand.   Hand (N Y). 2018;13(5):516-521. doi:10.1177/1558944717725377PubMedGoogle ScholarCrossref
24.
Carlton  A, Khalid  SI.  Surgical approaches and their outcomes in the treatment of cubital tunnel syndrome.   Front Surg. 2018;5(July):48. doi:10.3389/fsurg.2018.00048PubMedGoogle ScholarCrossref
25.
Kholinne  E, Alsharidah  MM, Almutair  O,  et al.  Revision surgery for refractory cubital tunnel syndrome: a systematic review.   Orthop Traumatol Surg Res. 2019;105(5):867-876. doi:10.1016/j.otsr.2019.03.020PubMedGoogle ScholarCrossref
26.
Salanti  G.  Indirect and mixed-treatment comparison, network, or multiple-treatments meta-analysis: many names, many benefits, many concerns for the next generation evidence synthesis tool.   Res Synth Methods. 2012;3(2):80-97. doi:10.1002/jrsm.1037PubMedGoogle ScholarCrossref
27.
Efthimiou  O, Debray  TPA, van Valkenhoef  G,  et al; GetReal Methods Review Group.  GetReal in network meta-analysis: a review of the methodology.   Res Synth Methods. 2016;7(3):236-263. doi:10.1002/jrsm.1195PubMedGoogle ScholarCrossref
28.
Salanti  G, Ades  AE, Ioannidis  JPA.  Graphical methods and numerical summaries for presenting results from multiple-treatment meta-analysis: an overview and tutorial.   J Clin Epidemiol. 2011;64(2):163-171. doi:10.1016/j.jclinepi.2010.03.016PubMedGoogle ScholarCrossref
29.
Higgins  JPT, Green  S, eds.  Cochrane Handbook for Systematic Reviews of Interventions, Version 5.1.0. Cochrane Collaboration; 2011.
30.
Moher  D, Liberati  A, Tetzlaff  J, Altman  DG; PRISMA Group.  Preferred Reporting Items for Systematic Reviews and Meta-analyses: the PRISMA statement.   Ann Intern Med. 2009;151(4):264-269, W64. doi:10.7326/0003-4819-151-4-200908180-00135PubMedGoogle ScholarCrossref
31.
Hutton  B, Salanti  G, Caldwell  DM,  et al.  The PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions: checklist and explanations.   Ann Intern Med. 2015;162(11):777-784. doi:10.7326/M14-2385PubMedGoogle ScholarCrossref
32.
Koziej  M, Trybus  M, Banach  M,  et al.  Comparison of patient-reported outcome measurements and objective measurements after cubital tunnel decompression.   Plast Reconstr Surg. 2018;141(5):1171-1181. doi:10.1097/PRS.0000000000004291PubMedGoogle ScholarCrossref
33.
Barry  MJ, Edgman-Levitan  S.  Shared decision making—pinnacle of patient-centered care.   N Engl J Med. 2012;366(9):780-781. doi:10.1056/NEJMp1109283PubMedGoogle ScholarCrossref
34.
Aagaard  T, Lund  H, Juhl  C.  Optimizing literature search in systematic reviews: are MEDLINE, EMBASE and CENTRAL enough for identifying effect studies within the area of musculoskeletal disorders?   BMC Med Res Methodol. 2016;16(1):161. doi:10.1186/s12874-016-0264-6PubMedGoogle ScholarCrossref
35.
Liu  C-H, Wu  S-Q, Ke  X-B,  et al.  Subcutaneous versus submuscular anterior transposition of the ulnar nerve for cubital tunnel syndrome: a systematic review and meta-analysis of randomized controlled trials and observational studies.   Medicine (Baltimore). 2015;94(29):e1207. doi:10.1097/MD.0000000000001207PubMedGoogle Scholar
36.
Capo  JT, Jacob  G, Maurer  RJ, Nourbakhsh  A, Preston  JS.  Subcutaneous anterior transposition versus decompression and medial epicondylectomy for the treatment of cubital tunnel syndrome.   Orthopedics. 2011;34(11):e713-e717. doi:10.3928/01477447-20110922-18PubMedGoogle Scholar
37.
Teo  MK, Trivedi  R, Waters  A.  The role of ulnar nerve transposition in ulnar entrapment neuropathy.   Br J Neurosurg. 2010;24(2):140. doi:10.3109/02688691003680382Google Scholar
38.
Izadpanah  A, Spinner  R, Kakar  S.  The efficacy of in-situ cubital tunnel release in management of elbow ulnar compression neuropathy in McGowan grade 3.   J Hand Surg Am. 2015;40(9). doi:10.1016/j.jhsa.2015.06.068Google Scholar
39.
Higgins  JP, Savović  J, Page  MJ, Sterne  JA.  Revised Cochrane Risk-of-Bias Tool for Randomized Trials (RoB2). Cochrane Library; 2016. doi:10.1002/14651858.CD201601
40.
Sterne  JA, Hernán  MA, Reeves  BC,  et al.  ROBINS-I: a tool for assessing risk of bias in non-randomised studies of interventions.   BMJ. 2016;355:i4919. doi:10.1136/bmj.i4919PubMedGoogle ScholarCrossref
41.
Nikolakopoulou  A, Higgins  JPT, Papakonstantinou  T,  et al.  CINeMA: an approach for assessing confidence in the results of a network meta-analysis.   PLoS Med. 2020;17(4):e1003082. doi:10.1371/journal.pmed.1003082PubMedGoogle Scholar
42.
Rücker  G, Krahn  U, König  J, Efthimiou  O, Schwarzer  G. Netmeta: Network meta-analysis using frequentist methods. Published 2019. Accessed June 2019. https://github.com/guido-s/netmeta
43.
Efthimiou  O, Mavridis  D, Debray  TPA,  et al; GetReal Work Package 4.  Combining randomized and non-randomized evidence in network meta-analysis.   Stat Med. 2017;36(8):1210-1226. doi:10.1002/sim.7223PubMedGoogle ScholarCrossref
44.
Rücker  G, Schwarzer  G.  Ranking treatments in frequentist network meta-analysis works without resampling methods.   BMC Med Res Methodol. 2015;15(1):58. doi:10.1186/s12874-015-0060-8PubMedGoogle ScholarCrossref
45.
Higgins  JPT, Jackson  D, Barrett  JK, Lu  G, Ades  AE, White  IR.  Consistency and inconsistency in network meta-analysis: concepts and models for multi-arm studies.   Res Synth Methods. 2012;3(2):98-110. doi:10.1002/jrsm.1044PubMedGoogle ScholarCrossref
46.
König  J, Krahn  U, Binder  H.  Visualizing the flow of evidence in network meta-analysis and characterizing mixed treatment comparisons.   Stat Med. 2013;32(30):5414-5429. doi:10.1002/sim.6001PubMedGoogle ScholarCrossref
47.
Krahn  U, Binder  H, König  J.  A graphical tool for locating inconsistency in network meta-analyses.   BMC Med Res Methodol. 2013;13(1):35. doi:10.1186/1471-2288-13-35PubMedGoogle ScholarCrossref
48.
Chaimani  A, Higgins  JPT, Mavridis  D, Spyridonos  P, Salanti  G.  Graphical tools for network meta-analysis in STATA.   PLoS One. 2013;8(10):e76654. doi:10.1371/journal.pone.0076654PubMedGoogle Scholar
49.
Efthimiou  O, Rücker  G, Schwarzer  G, Higgins  JPT, Egger  M, Salanti  G.  Network meta-analysis of rare events using the Mantel-Haenszel method.   Stat Med. 2019;38(16):2992-3012. doi:10.1002/sim.8158PubMedGoogle ScholarCrossref
50.
Viechtbauer  W.  Conducting meta-analyses in R with the metafor package.   J Stat Softw. 2010;36(3). doi:10.18637/jss.v036.i03Google Scholar
51.
Wasserstein  RL, Lazar  NA.  The ASA statement on p-values: context, process, and purpose.   Am Stat. 2016;70(2):129-133. doi:10.1080/00031305.2016.1154108Google ScholarCrossref
52.
Amrhein  V, Greenland  S, McShane  B.  Scientists rise up against statistical significance.   Nature. 2019;567(7748):305-307. doi:10.1038/d41586-019-00857-9PubMedGoogle ScholarCrossref
53.
Efthimiou  O, White  IR.  The dark side of the force: multiplicity issues in network meta-analysis and how to address them.   Res Synth Methods. 2020;11(1):105-122. doi:10.1002/jrsm.1377PubMedGoogle ScholarCrossref
54.
Charles  YP, Coulet  B, Rouzaud  J-C, Daures  J-P, Chammas  M.  Comparative clinical outcomes of submuscular and subcutaneous transposition of the ulnar nerve for cubital tunnel syndrome.   J Hand Surg Am. 2009;34(5):866-874. doi:10.1016/j.jhsa.2009.01.008PubMedGoogle ScholarCrossref
55.
Dützmann  S, Martin  KD, Sobottka  S,  et al.  Open vs retractor-endoscopic in situ decompression of the ulnar nerve in cubital tunnel syndrome: a retrospective cohort study.   Neurosurgery. 2013;72(4):605-616. doi:10.1227/NEU.0b013e3182846dbdPubMedGoogle ScholarCrossref
56.
Gervasio  O, Gambardella  G, Zaccone  C, Branca  D.  Simple decompression versus anterior submuscular transposition of the ulnar nerve in severe cubital tunnel syndrome: a prospective randomized study.   Neurosurgery. 2005;56(1):108-117. doi:10.1227/01.NEU.0000145854.38234.81PubMedGoogle ScholarCrossref
57.
Geutjens  GG, Langstaff  RJ, Smith  NJ, Jefferson  D, Howell  CJ, Barton  NJ.  Medial epicondylectomy or ulnar-nerve transposition for ulnar neuropathy at the elbow?   J Bone Joint Surg Br. 1996;78(5):777-779. doi:10.1302/0301-620X.78B5.0780777PubMedGoogle ScholarCrossref
58.
Hahn  SB, Choi  YR, Kang  HJ, Kang  ES.  Decompression of the ulnar nerve and minimal medial epicondylectomy with a small incision for cubital tunnel syndrome: comparison with anterior subcutaneous transposition of the nerve.   J Plast Reconstr Aesthet Surg. 2010;63(7):1150-1155. doi:10.1016/j.bjps.2009.09.018PubMedGoogle ScholarCrossref
59.
Heikenfeld  R, Godolias  G.  Ulnar nerve decompression in cubital tunnel syndrome: open in situ decompression versus endoscopic decompression.   Arthrosc J Arthrosc Relat Surg. 2013;29(10):e98. doi:10.1016/j.arthro.2013.07.110Google Scholar
60.
Jaddue  DA, Saloo  SA, Sayed-Noor  AS.  Subcutaneous vs submuscular ulnar nerve transposition in moderate cubital tunnel syndrome.   Open Orthop J. 2009;3(1):78-82. doi:10.2174/1874325000903010078PubMedGoogle ScholarCrossref
61.
Kamat  AS, Jay  SM, Benoiton  LA, Correia  JA, Woon  K.  Comparative outcomes of ulnar nerve transposition versus neurolysis in patients with entrapment neuropathy at the cubital tunnel: a 20-year analysis.   Acta Neurochir (Wien). 2014;156(1):153-157. doi:10.1007/s00701-013-1962-zPubMedGoogle ScholarCrossref
62.
Keiner  D, Gaab  MR, Schroeder  HW, Oertel  J.  Comparison of the long-term results of anterior transposition of the ulnar nerve or simple decompression in the treatment of cubital tunnel syndrome—a prospective study.   Acta Neurochir (Wien). 2009;151(4):311-315. doi:10.1007/s00701-009-0218-4PubMedGoogle ScholarCrossref
63.
Köse  KÇ, Bilgin  S, Cebesoy  O,  et al.  Clinical results versus subjective improvement with anterior transposition in cubital tunnel syndrome.   Adv Ther. 2007;24(5):996-1005. doi:10.1007/BF02877704PubMedGoogle ScholarCrossref
64.
Krejčí  T, Večeřa  Z, Krejčí  O, Šalounová  D, Houdek  M, Lipina  R.  Comparing endoscopic and open decompression of the ulnar nerve in cubital tunnel syndrome: a prospective randomized study.   Acta Neurochir (Wien). 2018;160(10):2011-2017. doi:10.1007/s00701-018-3647-0PubMedGoogle ScholarCrossref
65.
Luo  S, Zhao  J, Su  W, Li  X.  Efficacy comparison between anterior subcutaneous and submuscular transposition of ulnar nerve to treat cubital tunnel syndrome.   Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2010;24(5):577-580.PubMedGoogle Scholar
66.
Martin  K-D, Dützmann  S, Sobottka  SB,  et al.  Retractor-endoscopic nerve decompression in carpal and cubital tunnel syndromes: outcomes in a small series.   World Neurosurg. 2014;82(1-2):e361-e370. doi:10.1016/j.wneu.2013.09.026PubMedGoogle ScholarCrossref
67.
Mitsionis  GI, Manoudis  GN, Paschos  NK, Korompilias  AV, Beris  AE.  Comparative study of surgical treatment of ulnar nerve compression at the elbow.   J Shoulder Elbow Surg. 2010;19(4):513-519. doi:10.1016/j.jse.2009.10.014PubMedGoogle ScholarCrossref
68.
Schmidt  S, Kleist Welch-Guerra  W, Matthes  M, Baldauf  J, Schminke  U, Schroeder  HWS.  Endoscopic vs open decompression of the ulnar nerve in cubital tunnel syndrome: a prospective randomized double-blind study.   Neurosurgery. 2015;77(6):960-970. doi:10.1227/NEU.0000000000000981PubMedGoogle ScholarCrossref
69.
Stuffer  M, Jungwirth  W, Hussl  H, Schmutzhardt  E.  Subcutaneous or submuscular anterior transposition of the ulnar nerve?   J Hand Surg Br. 1992;17(3):248-250. doi:10.1016/0266-7681(92)90107-DPubMedGoogle ScholarCrossref
70.
Tong  J, Xu  B, Dong  Z, Zhang  C, Gu  Y.  Surgical outcome for severe cubital tunnel syndrome in patients aged >70 years: a mean follow-up of 4.5 years.   Acta Neurochir (Wien). 2017;159(5):917-923. doi:10.1007/s00701-017-3113-4PubMedGoogle ScholarCrossref
71.
Watts  AC, Bain  GI.  Patient-rated outcome of ulnar nerve decompression: a comparison of endoscopic and open in situ decompression.   J Hand Surg Am. 2009;34(8):1492-1498. doi:10.1016/j.jhsa.2009.05.014PubMedGoogle ScholarCrossref
72.
Zhang  D, Earp  BE, Blazar  P.  Rates of complications and secondary surgeries after in situ cubital tunnel release compared with ulnar nerve transposition: a retrospective review.   J Hand Surg Am. 2017;42(4):294.e1-294.e5. doi:10.1016/j.jhsa.2017.01.020PubMedGoogle ScholarCrossref
73.
Zhou  Y, Feng  F, Qu  X,  et al.  Effectiveness comparison between two different methods of anterior transposition of the ulnar nerve in treatment of cubital tunnel syndrome.   Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2012;26(4):429-432.PubMedGoogle Scholar
74.
Asamoto  S, Böker  D-K, Jödicke  A.  Surgical treatment for ulnar nerve entrapment at the elbow.   Neurol Med Chir (Tokyo). 2005;45(5):240-244. doi:10.2176/nmc.45.240PubMedGoogle ScholarCrossref
75.
Bacle  G, Marteau  E, Freslon  M,  et al.  Cubital tunnel syndrome: comparative results of a multicenter study of 4 surgical techniques with a mean follow-up of 92 months.   Orthop Traumatol Surg Res. 2014;100(4)(suppl):S205-S208. doi:10.1016/j.otsr.2014.03.009PubMedGoogle ScholarCrossref
76.
Baek  GH, Kwon  BC, Chung  MS.  Comparative study between minimal medial epicondylectomy and anterior subcutaneous transposition of the ulnar nerve for cubital tunnel syndrome.   J Shoulder Elbow Surg. 2006;15(5):609-613. doi:10.1016/j.jse.2005.10.007PubMedGoogle ScholarCrossref
77.
Bartels  RHMA, Verhagen  WIM, van der Wilt  GJ, Meulstee  J, van Rossum  LGM, Grotenhuis  JA.  Prospective randomized controlled study comparing simple decompression versus anterior subcutaneous transposition for idiopathic neuropathy of the ulnar nerve at the elbow: part 1.   Neurosurgery. 2005;56(3):522-530. doi:10.1227/01.NEU.0000154131.01167.03PubMedGoogle ScholarCrossref
78.
Biggs  M, Curtis  JA.  Randomized, prospective study comparing ulnar neurolysis in situ with submuscular transposition.   Neurosurgery. 2006;58(2):296-304. doi:10.1227/01.NEU.0000194847.04143.A1PubMedGoogle ScholarCrossref
79.
Bimmler  D, Meyer  VE.  Surgical treatment of the ulnar nerve entrapment neuropathy: submuscular anterior transposition or simple decompression of the ulnar nerve? long-term results in 79 cases.   Ann Chir Main Memb Super. 1996;15(3):148-157. doi:10.1016/S0753-9053%2896%2980005-6PubMedGoogle Scholar
80.
Bolster  MAJ, Zöphel  OT, van den Heuvel  ER, Ruettermann  M.  Cubital tunnel syndrome: a comparison of an endoscopic technique with a minimal invasive open technique.   J Hand Surg Eur Vol. 2014;39(6):621-625. doi:10.1177/1753193413498547PubMedGoogle ScholarCrossref
81.
Kazmers  NH, Lazaris  EL, Allen  CM, Presson  AP, Tyser  AR.  Comparison of surgical encounter direct costs for three methods of cubital tunnel decompression.   Plast Reconstr Surg. 2019;143(2):503-510. doi:10.1097/PRS.0000000000005196PubMedGoogle ScholarCrossref
82.
Malay  S, Chung  KC; SUN Study Group.  The minimal clinically important difference after simple decompression for ulnar neuropathy at the elbow.   J Hand Surg Am. 2013;38(4):652-659. doi:10.1016/j.jhsa.2013.01.022PubMedGoogle ScholarCrossref
83.
Kooner  S, Cinats  D, Kwong  C, Matthewson  G, Dhaliwal  G.  Conservative treatment of cubital tunnel syndrome: a systematic review.   Orthop Rev (Pavia). 2019;11(2):7955. doi:10.4081/or.2019.7955PubMedGoogle ScholarCrossref
84.
Smith  T, Nielsen  KD, Poulsgaard  L.  Ulnar neuropathy at the elbow: clinical and electrophysiological outcome of surgical and conservative treatment.   Scand J Plast Reconstr Surg Hand Surg. 2000;34(2):145-148. doi:10.1080/02844310050160006PubMedGoogle ScholarCrossref
85.
Wade  RG, Bland  JM, Wormald  JCR, Figus  A.  The importance of the unit of analysis: commentary on Beugels et al. (2016)—complications in unilateral versus bilateral deep inferior epigastric artery perforator flap breast reconstructions: a multicentre study.   J Plast Reconstr Aesthet Surg. 2016;69(9):1299-1300. doi:10.1016/j.bjps.2016.06.002PubMedGoogle ScholarCrossref
×