Schweitzer Timothy P, Rayan Ghazi M
Hand Surgery Section, Orthopedic Surgery Department, University of Oklahoma Health Sciences Center and Integris Baptist Medical Center, Oklahoma City, OK 73112, USA.
J Hand Surg Am. 2004 Sep;29(5):903-8. doi: 10.1016/j.jhsa.2004.04.025.
To conduct kinematic analyses of both intact and sectioned terminal tendon (TT) of multiple fingers in the hand.
The TTs of 36 fresh-frozen cadaveric digits were used in this study. TT excursion was assessed along with the influence on proximal joint motion. The influence of TT lengthening and shortening on distal interphalangeal (DIP) joint motion were investigated.
TT excursion averaged 1 mm at the DIP joint and was influenced by the proximal interphalangeal (PIP) joint but not the position of other joints in the hand and wrist. The greatest degree of DIP joint motion averaged 86 degrees when the PIP joint was in full flexion, whereas the least motion averaged 45 degrees when this joint was in neutral position. Lengthening of the TT resulted in angular deformity at the DIP joint. Average flexion deformities reached 25 degrees at 1 mm, 36 degrees at 2 mm, 49 degrees at 3 mm, and 63 degrees at 4 mm of lengthening. The middle finger showed the greatest flexion deformity, followed by the ring, small, and index fingers. Shortening the TT by as little as 1 mm resulted in difficult tendon repair because of excessive tension and minimal or no DIP joint flexion was obtained.
Only DIP and PIP joints affect TT excursion; hence these are the main joints to be immobilized to protect TT repair. The middle finger TT showed the least tolerance to lengthening with potential for mallet deformity. Joint flexion deformity is proportional to tendon lengthening. Only 1 mm of TT lengthening results in approximately 25 degrees of DIP joint extension lag, and 4 mm of TT lengthening results in DIP joint flexion deformity greater than 60 degrees . Even 1 mm of TT shortening will seriously restrict DIP joint flexion.
对手部多个手指完整和离断的终末肌腱（TT）进行运动学分析。
本研究使用了36个新鲜冷冻尸体手指的TT。评估了TT的移动情况以及对近端关节运动的影响。研究了TT延长和缩短对远侧指间（DIP）关节运动的影响。
DIP关节处TT移动平均为1mm，受近端指间（PIP）关节影响，但不受手和腕部其他关节位置的影响。当PIP关节完全屈曲时，DIP关节最大运动度平均为86度，而当该关节处于中立位时，最小运动度平均为45度。TT延长导致DIP关节出现角形畸形。延长1mm时平均屈曲畸形达25度，2mm时为36度，3mm时为49度，4mm时为63度。中指屈曲畸形最大，其次是环指、小指和示指。TT缩短仅1mm就会因张力过大导致肌腱修复困难，且DIP关节几乎无法屈曲或完全不能屈曲。
仅DIP和PIP关节影响TT移动；因此，这些是固定以保护TT修复的主要关节。中指TT对延长的耐受性最差，有发生锤状畸形的可能。关节屈曲畸形与肌腱延长成正比。TT延长仅1mm会导致DIP关节伸展滞后约25度，TT延长4mm会导致DIP关节屈曲畸形大于60度。即使TT缩短1mm也会严重限制DIP关节屈曲。
