Subcutaneous rupture of the tendinous segment of the extensor pollicis longus muscle as a late complication of a Colles fracture is extremely uncommon. Recently (January 1932) McMaster1 found only twenty-seven such cases reported in the literature and added an additional case. Included in McMaster's contribution is the only available instance of a rupture of the tendon of the flexor pollicis longus muscle following a Colles fracture. Four cases of late rupture of the extensor pollicis longus tendon are reported by Horwitz2 from Bier's clinic; two were associated with a Colles fracture, one with fracture of the base of the first metacarpal bone and one with osteitis fibrosa cystica of the styloid process of the radius.
Auxhausen expressed the opinion that rupture of this tendon is not as rare as is generally believed, since he and Hauck observed ten such cases. Platt's3 experience suggested a similar point of
LIPSHUTZ B. LATE SUBCUTANEOUS RUPTURE OF THE TENDON OF THE EXTENSOR POLLICIS LONGUS MUSCLE. Arch Surg. 1935;31(5):816-822. doi:10.1001/archsurg.1935.01180170141011