Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi 110029, India.
Singapore Med J. 2012 Jun;53(6):e133-5.
The anomalous orientation of musculature of the first dorsal fibro-osseous compartment of the wrist is clinically relevant to De Quervian's stenosing tenosynovitis and reconstructive surgeries. Split insertion of the abductor pollicis longus (APL) is commonly found in chimpanzees, gorillas and gibbons. A comparable identical pattern of anomalous slips in humans is of anthropological and phylogenetic importance and could be a result of atavism. This case report describes an unusual fused muscle belly of the APL and extensor pollicis brevis (EPB), which split into three slips--medial, intermediate and lateral. Further, the medial slip was seen to divide into two tendons, inserting on the base of the first metacarpal along with the intermediate slip. The lateral slip divided into three tendons, inserting into the base of the proximal phalanx, base of the first metacarpal and abductor pollicis brevis muscle. The fusion and unusual insertion pattern of the APL and EPB merits documentation for reconstructive procedures such as tendon transfer and interposition arthroplasty.
腕部第一背侧纤维骨性间隔的肌肉异常取向与德奎文氏狭窄性腱鞘炎和重建手术密切相关。在黑猩猩、大猩猩和长臂猿中，通常可以发现拇长展肌（APL）的分裂插入。人类中类似的异常滑肌模式具有人类学和系统发育学的重要性，可能是返祖现象的结果。本病例报告描述了一种不寻常的 APL 和伸拇指短肌（EPB）融合的肌腹，它分裂成三个滑肌——内侧、中间和外侧。此外，内侧滑肌分为两条肌腱，与中间滑肌一起插入第一掌骨基部。外侧滑肌分为三条肌腱，插入近节指骨基部、第一掌骨基部和拇指外展短肌。APL 和 EPB 的融合和异常插入模式值得记录，以便于进行肌腱转移和间置关节成形术等重建手术。
