Srinivasan H
J Bone Joint Surg Am. 1976 Sep;58(6):777-85.
A detailed study of metacarpophalangeal flexion and interphalangeal extension movements of 141 fingers with complete intrinsic-muscle paralysis due to leprosy showed that long flexors and long extensors produce movement at the metacarpophalangeal and proximal interphalangeal joints simultaneously, and not successively as is generally believed. The amounts of flexion resulting from long flexor activity are almost equal at the two joints and metacarpophalangeal flexion is achieved without excessive flexion of the proximal interphalangeal joint, but this is masked by the claw-finger deformity. The movement resulting from activity of the long extensor is complex and there are three or more qualitatively different patterns of extension. Although the long extensor produces simultaneous extension at the metacarpophalangeal and proximal interphalangeal joints, the latter consistently lags behind the former so that full extension is not achieved at the proximal interphalangeal joint even when the metacarpophalangeal joint is maximally extended. The diverse patterns of extension are not related to duration of degree of clawing or to any particular finger.
一项对141根因麻风导致完全性固有肌麻痹的手指的掌指关节屈曲和指间关节伸展运动的详细研究表明，长屈肌和长伸肌同时而非如普遍认为的那样先后在掌指关节和近端指间关节产生运动。长屈肌活动所导致的屈曲量在两个关节处几乎相等，且掌指关节屈曲时近端指间关节不会过度屈曲，但这被爪形指畸形所掩盖。长伸肌活动所产生的运动较为复杂，存在三种或更多性质不同的伸展模式。尽管长伸肌在掌指关节和近端指间关节同时产生伸展，但后者始终落后于前者，以至于即使掌指关节最大程度伸展时，近端指间关节也无法实现完全伸展。伸展的不同模式与爪形指的持续时间或程度无关，也与任何特定手指无关。
