Orosz GM, Magaziner J, Hannan EL, Morrison RS, Koval K, Gilbert M, McLaughlin M, Halm EA, Wang JJ, Litke A, Silberzweig SB, Siu AL. Association of Timing of Surgery for Hip Fracture and Patient Outcomes. JAMA. 2004;291(14):1738-1743. doi:10.1001/jama.291.14.1738
Author Affiliations: Department of Geriatrics (Drs Orosz, Morrison, and Siu, and Mss Litke and Silberzweig), Department of Orthopedics (Dr Gilbert), Department of Medicine (Drs McLaughlin and Halm), and Department of Health Policy (Dr Wang), Mount Sinai School of Medicine, New York, NY; Department of Epidemiology and Preventive Medicine, School of Medicine, University of Maryland, Baltimore (Dr Magaziner); Department of Health Policy and Management, State University of New York, University at Albany School of Public Health (Dr Hannan); Department of Orthopedics, Hospital for Joint Diseases, New York, NY (Dr Koval); and Bronx VA Medical Center GRECC, Bronx, NY (Dr Siu).
Context Previous studies of surgical timing in patients with hip fracture have
yielded conflicting findings on mortality and have not focused on functional
Objective To examine the association of timing of surgical repair of hip fracture
with function and other outcomes.
Design Prospective cohort study including analyses matching cases of early
(≤24 hours) and late (>24 hours) surgery with propensity scores and excluding
patients who might not be candidates for early surgery.
Setting Four hospitals in the New York City metropolitan area.
Participants A total of 1206 patients aged 50 years or older admitted with hip fracture
over 29 months, ending December 1999.
Main Outcome Measures Function (using the Functional Independence Measure), survival, pain,
and length of stay (LOS).
Results Of the patients treated with surgery (n = 1178), 33.8% had surgery within
24 hours. Earlier surgery was not associated with improved mortality (hazard
ratio, 0.75; 95% confidence interval [CI], 0.52-1.08) or improved locomotion
(difference of −0.04 points; 95% CI, –0.49 to 0.39). Earlier surgery
was associated with fewer days of severe and very severe pain (difference
of −0.22 days; 95% CI, −0.41 to −0.03) and shorter LOS by
1.94 days (P<.001), but postoperative pain and
LOS after surgery did not differ. Analyses with propensity scores yielded
similar results. When the cohort included only patients who were medically
stable at admission and therefore eligible for early surgery, the results
were unchanged except that early surgery was associated with fewer major complications
(odds ratio, 0.26; 95% CI, 0.07-0.95).
Conclusions Early surgery was not associated with improved function or mortality,
but it was associated with reduced pain and LOS and probably major complications
among patients medically stable at admission. Additional research is needed
on whether functional outcomes may be improved. In the meantime, patients
with hip fracture who are medically stable should receive early surgery when
The incidence of hip fracture is increasing in the United States, with
more than 340 000 occurring in the year 2000.1 In
elderly patients, the 1-year mortality rate for hip fracture ranges from 14%
to 36%.2 Additionally, hip fracture is associated
with poor functional outcomes.3,4
Surgical repair is a key element in the management of hip fracture.
Before surgery, most patients are confined to bed rest. In theory, delay in
surgery and mobilization could affect functional and other outcomes by increasing
bed rest–associated complications, including thromboembolism,5 urinary tract infections,6 atelectasis,
and pressure ulcers.7 On the other hand, precipitous
surgery and failing to stabilize medical problems could increase the risk
of perioperative complications.
Whether early surgery is beneficial is a long-running controversy and
is one of the most common clinical issues in the early acute management of
these patients. A randomized trial of surgical timing in hip fracture has
never been conducted, but the relationship of timing and outcomes has been
examined in other studies.8- 20 Many
of these studies did not adjust for comorbid illness or other parameters that
might be used to "select" patients for earlier surgery. Of the studies that
controlled for comorbidity,11,14,16,17,19 some
found that early surgery is associated with lower mortality, LOS, and complications.
A more recent, large study,20 however, found
that surgery after 48 hours was not associated with increased mortality compared
with surgery in 24 to 48 hours. Of note, virtually all studies evaluated the
association of early surgery with mortality rather than functional outcomes.
We examined the association of the timing of hip fracture surgery with mortality,
functional outcomes, pain, length of stay (LOS), and complications.
Consecutive admissions to 4 hospitals in the New York City metropolitan
area were screened for cases of hip fracture for 29 months ending December
1999. The hospitals included 1 academic medical center, an urban teaching
hospital, an orthopedics hospital, and a suburban hospital. Exclusion criteria
included patient age younger than 50 years, fractures that occurred as an
inpatient, transfers from another hospital, multiple trauma, pathological
fractures, distal and femoral shaft fractures, bilateral hip fractures, or
previous fracture or surgery on the currently fractured site. The study was
approved by the institutional review boards at the 4 participating hospitals.
All patients provided verbal informed consent. Of the 1741 cases admitted,
23.4% met exclusionary criteria, 4.1% refused to participate, 2.6% were discharged
before consent could be obtained, 0.6% had incomplete data, and 69.3% (n =
1206) were enrolled.
Trained research associates enrolled patients as early in the admission
as possible (69% were enrolled on or before the day of surgery). Information
on prefracture function, residential location, and history of dementia was
collected from patients or their proxies (if the patient was delirious or
cognitively impaired). Information on each patient's functional status for
the 2 weeks prior to fracture was obtained by interview using the motor scale
of the Functional Independence Measure (FIM),21 which
consists of 13 items in 4 subscales of physical functioning (locomotion, self-care,
toileting, and transferring). Each item was scored between 1 (for complete
dependence) and 7 (for complete independence) using specific criteria. Medical
records were reviewed throughout the hospital admission to collect information
on comorbid medical problems, type of fracture, and other aspects of medical
Information was also collected on abnormal clinical findings (admission
physical examination and laboratory findings) that are commonly available
and used by clinicians to decide whether to delay surgery. This information
was used to determine whether the patient had (1) a systolic blood pressure
of 90 mm Hg or less; (2) a rate or rhythm abnormality (defined as atrial fibrillation
or supraventricular tachycardia at a rate greater than 120/min, ventricular
tachycardia, 3° block, or a rate of ≤45/min); (3) chest pain or myocardial
infarction within 3 months; (4) poorly compensated heart failure (a chest
x-ray consistent with congestive heart failure, the presence of dyspnea, abnormal
lung findings [eg, rales, rhonchi, and decreased breath sounds] or an S3 gallop); (5) an abnormal international normalized ratio of 1.4 or
higher; and (6) a laboratory abnormality (sodium <125 or >155 mEq/L; potassium
<2.5 or >6.1 mEq/L; bicarbonate <18 or >36 mEq/L; glucose >600 mg/dL
[33.3 mmol/L]; serum urea nitrogen >50 mg/dL [17.8 mmol/L]; creatinine >2.5
mg/dL [221 µmol/L]; hemoglobin ≤7.5 g/dL; a pulse oximetry reading
of <90%; PO2 <60 mm Hg; or PCO2 >55 mm Hg). Cutoff
values were established by examining the relationship between the occurrence
of early surgery and the range of values for each finding.
For the patients enrolled during the first 12 months, each patient was
also seen 5 days a week in the hospital to collect additional information
on pain and complications. At each visit, the patient was asked to assess
pain severity for the previous 24 or 48 hours (on a 5-point scale ranging
from no pain to very severe pain). The hospital course and medical record
were reviewed at each visit, and complications were recorded. Major complications
were defined as those that posed a threat to life or bodily functions and
that typically are treated with parenteral medications, procedures, or intensive
monitoring. Examples of major complications include (1) pneumonia if both
respiratory symptoms and/or hypoxia were documented, and (2) arrhythmias if
their occurrence increased the risk of ischemia or hemodynamic compromise.
Nurses identifying complications were not aware of the study hypothesis. Physicians
who categorized complications as to whether they were true complications or
arose from a preexisting condition were not blinded as to surgical timing.
All patients were followed up, and information on functional status
and mortality was obtained by telephone at 6 months. Additional deaths were
identified from hospital records and vital statistics. Ascertainment of death
or functional outcome was available for 94.0% of participants at 6 months.
We compared patients having surgery within 24 hours with those having
surgery after 24 hours on the following outcomes: (1) mean pain scores over
the first 5 hospital days; (2) number of days of severe and very severe pain
over hospital days 1 to 5 (assessed by asking patients if they were experiencing
no pain, or mild, moderate, or severe pain); (3) major postoperative complications;
(4) LOS; (5) mortality through 6 months; (6) FIM locomotion (a 2-item subscale
focusing on walking and climbing stairs) score at 6 months; (7) FIM self-care
(a 6-item scale of self-care activities including bathing and dressing); and
(8) FIM transferring (a 3-item scale focusing on transfers from the bed, toilet,
and tub). The analyses of complications (n = 554) and pain (n = 487 patients
able to report on pain) were limited to patients enrolled in the first 12
months. Other analyses involved data from all enrolled patients having surgery.
We focused on pain over the first 5 hospital days because we were interested
in cumulative pain burden rather than preoperative or postoperative pain that
would have been difficult to compare between the early and later surgery groups.
For the FIM measures, analyses were restricted to survivors. We excluded patients
who were totally or maximally dependent on walking at baseline (n = 75) from
analyses of FIM locomotion because the scale could not be responsive to worsening
in these patients due to a "floor" effect. To test the sensitivity of our
results to the exclusion of survivors, we also examined the effect on a combined
measure of mortality or needing total assistance in locomotion.22
Using ordinary least squares regression (for continuous outcomes), logistic
regression (for binary outcomes), or Cox proportional hazards regression for
our main analyses, we controlled for age, sex, nursing home residence, needing
a proxy for consent, delirium on admission, prefracture FIM locomotion score,
fracture type, hospitalization within 6 months, hospital site, day and time
of admission, abnormal clinical findings, and history of diabetes, chronic
obstructive pulmonary disease, stroke syndrome, dementia, cardiac disease,
and hypertension. Odds ratios (ORs) were adjusted to approximate the relative
We performed 2 types of supplementary or sensitivity analyses. First,
we performed an analysis using propensity scores24,25 to
match patients for whom the likelihood of having early surgery was similar.
In the first step, we used stepwise logistic regression to generate a propensity
score for having early surgery for each patient using the available variables.
Each case of surgery within 24 hours was then matched with a case having later
surgery based on the closest propensity score (within 10%) and closest age
(when multiple matches were obtained). We compared patients having surgery
within 24 hours to matching cases having surgery after 24 hours.
As our second supplementary analysis, we examined whether the results
changed when we excluded patients who might not be candidates for early surgery
because of markedly abnormal clinical findings or the need for additional
time for preoperative evaluation. Thus, the restricted cohort excludes patients
admitted with abnormal clinical findings, aortic stenosis, dementia, and end-stage
renal disease on dialysis. All analyses were performed using STATA, release
7 (STATA, College Station, Tex). P<.05 was considered
Twenty-eight patients (2.3%) did not have surgery and were excluded
from the analyses. Of the remaining patients (n = 1178), 33.8% (n = 398) had
surgery 24 hours or less after hospital arrival. The median time to surgery
was 19 hours (interquartile range, 15-22 hours) in the early surgery group
and 40.6 hours (interquartile range, 29-53 hours) in the late surgery group.
Compared with patients who went to surgery within 24 hours, patients who had
later surgery (n = 780) were less likely to have been admitted from nursing
homes (P = .04) and were more likely to have poorly
compensated heart failure (P<.001), abnormal international
normalized ratio (P<.001), and other laboratory
abnormalities (P = .02) (Table 1). Having surgery within 24 hours also varied by hospital
site, by day of the week, and time of admission.
The overall unadjusted mortality was 8.2% at 2 months and 17.5% at 6
months (unadjusted hazard ratio for early surgery was 0.68; 95% confidence
interval [CI], 0.48-0.97; P = .03). After adjustment
for the factors shown in Table 2,
earlier surgery was not associated with improved mortality (hazard ratio,
0.75; 95% CI, 0.52-1.08; P = .12).
Pain control was assessed in 487 of the 554 patients enrolled in the
first 12 months. Patients enrolled in the first 12 months were similar to
those enrolled later except that they were slightly less likely to have delirium
on admission, had slightly lower admission FIM scores, were more likely to
have a cardiac history, and be admitted in the previous 6 months (data available
from authors on request). Patients who responded to questions on pain had
better function, were younger, and were less likely to have dementia than
those who did not (data available from authors on request). Compared with
patients having later surgery, earlier surgery was associated with lower pain
scores (difference of −0.24 points; 95% CI, −0.44 to −0.06)
and fewer days of severe and very severe pain for the first 5 days of hospitalization
(difference of −0.22 days; 95% CI, −0.41 to −0.03 [Figure 1]). Early surgery was also associated
with shorter LOS by 1.94 days (P<.001). The differences
in pain and LOS were accounted for by the delay in surgery; postoperative
pain and LOS were equivalent. Early surgery was associated with improved FIM
self-care (P = .04), but not fewer complications
(P = .10). FIM locomotion scores did not differ at
6 months (difference of −0.04 points; 95% CI, –0.49 to 0.39).
The relationship of surgical timing with FIM locomotion score was similar
when we used different time frames (surgery within 24 hours, within 24-48
hours, or after 48 hours of arrival) for surgery (data available on request).
The logistic regression to derive the propensity score had a C statistic of 0.68. Of the cases who had surgery within 24 hours (n
= 398), 373 (93.7%) were successfully matched. No significant differences
were found between the 2 matched groups for the characteristics listed in Table 1. Earlier surgery was not associated
with improved mortality (OR, 0.98; 95% CI, 0.63-1.50; P = .99) in propensity score–matched cases. Early surgery was
associated with reduced pain and LOS (Table
3), but not complications or FIM functional status measures at 6
In the restricted cohort, early surgery continued to be associated with
reduced pain and LOS (Table 2).
Number of days of severe and very severe pain was −0.30 days fewer in
the early surgery group (95% CI, –0.50 to −0.08). Additionally,
early surgery was associated with reduced major postoperative complications
(P = .04). Early surgery was not associated with
functional outcomes or mortality in the restricted cohort (Table 2).
Previous studies have yielded conflicting results on the relationship
of early surgery for hip fracture and survival, and the relationship of early
surgery and functional outcomes and pain is unknown. In this study, we found
that compared with later surgery surgery in the first 24 hours was not associated
with either improved or worsened survival and function at 6 months, a time
frame during which most recovery will occur.3,4 On
the other hand, early surgery was consistently associated with decreased LOS
and less pain and probably with reduced major complications among patients
who were medically stable at admission. In an earlier study,26 we
reported that clinical reasons (waiting for test results or for medical stabilization)
were infrequent reasons for delayed surgery in patients operated on between
24 and 48 hours after admission. Instead, system problems (timely consultation
or availability of the surgeon or operating room) accounted for most delays.
Thus, it is feasible to improve surgical timing that could in turn translate
to improved efficiency and reductions in severe pain.
In the case of mortality, our finding is consistent with those of a
recent study of 8383 patients in which no association was found when mortality
was compared in early (defined as 24-48 hours) and later surgery.20 Patients with surgery in the first 24 hours were
excluded; thus, our study goes beyond that analysis by considering surgical
timing from the time of admission—a better test of the early surgery
hypothesis. In the case of functional outcomes, several explanations exist
for the null finding. First, the benefit could be small. For example, we hypothesized
that reduced pain might translate to improved function based on an earlier
study,27 but the effect of earlier surgery
on reduced pain may be too small or too short in duration to make a difference
on function. Second, the functional benefit may be limited to a subgroup of
patients and obscured in analyses focusing on the average patient. Third,
the benefit from early surgery may be limited and short-lived if it is not
followed up by timely mobilization, early rehabilitation,28 and
attention to postacute care.
This study is the largest study of hip fracture we know of that has
detailed clinical information (beyond administrative data and medical records)
on the hospital course, as well as information on functional outcomes through
6 months. Nevertheless, our study was limited by reliance on self-report for
functional status, by reduced statistical power for selected outcomes, and
by the observational study design.
In the case of measuring function, we selected our methods knowing that
prefracture function is an important predictor of outcomes. Since observing
function before the fracture is not feasible, a measure that involved reporting
of functional status was needed. We selected what we considered to be the
most appropriate interview measure given that a considerable fraction of hip
fracture patients would need proxy respondents because of dementia or delirium.
The literature on proxy respondents indicates that agreement between patients
and proxies is greatest for questions that focus on discrete and observable
tasks, as were the measures we used, relative to questions that may ask about
perceived limitations in doing those tasks.
For functional outcomes, the 95% CI for the FIM locomotion scale showed
that it is unlikely that early surgery improved or worsened locomotion by
more than half a point, and we believe that clinically significant differences
were excluded. For example, the difference in 6-month mortality between a
prefracture FIM locomotion score of 6 vs 8 (2-point difference) was 21% vs
15%; the mortality difference for a half point would be extremely small. Furthermore,
an unadjusted association between early surgery and improved mortality diminished
after adjustment for other risk factors; the benefit was largely eliminated
in analyses involving propensity score matching or a restricted cohort. Although
we could not exclude a moderately large benefit of early surgery, the 95%
CI (0.52-1.08 for the hazard ratio) in the main adjusted analysis indicates
that anything more than a small increase in mortality from early surgery is
unlikely. Finally, we showed that early surgery was consistently associated
with shortened LOS and reduced pain. In addition, the number of fewer days
of severe or very severe pain with early surgery (0.22-0.30 days or 5-7 fewer
hours of severe pain on average) suggests that this is a clinically significant
Although our study was observational, we attempted to control for selection
in several ways. First, our analyses adjusted for a range of variables used
by clinicians to select patients for early surgery. These measures go beyond
those available from administrative data and include information on function
collected from interviews. Second, we also used propensity score methods to
match cases of early and late surgery. Finally, we repeated our analyses excluding
patients who might not be appropriate candidates for early surgery. Given
that a randomized trial of early vs delayed surgery is not likely to be done,
we believe that this important clinical question can only be answered by careful
observational research methods.
In conclusion, early surgery alone does not appear to have a beneficial
effect on mortality or function for the average patient with hip fracture.
However, early surgery was associated with less pain, reduced LOS, and probably
fewer major complications among patients who were medically stable at admission.
Further studies are needed that focus on the functional impact of early surgery
on subgroups of patients. Additionally, research is needed on whether the
theoretical benefits of early surgery on functional outcomes may be achieved
when early surgery is combined with the timely provision of mobilization,
rehabilitation, and the full range of postacute medical services. In the meantime,
early surgery should be a goal for most medically stable patients with hip
fracture, given that adverse events are unlikely and that pain, LOS, and possibly
complications will be reduced.