Krause Fabian Götz, Aebi Hansjürg, Lehmann Oliver, Weber Martin
Department of Orthopaedic Surgery, Inselspital Berne, Switzerland.
Foot Ankle Int. 2007 Feb;28(2):255-62. doi: 10.3113/FAI.2007.0255.
The inevitable detachment of tendons and the loss of the forefoot in Chopart and Lisfranc amputations result in equinus and varus of the residual foot. In an insensate foot these deformities can lead to keratotic lesions and ulcerations. The currently available prostheses cannot safely counteract the deforming forces and the resulting complications.
A new below-knee prosthesis was developed, combining a soft socket with a rigid shaft. The mold is taken with the foot in the corrected position. After manufacturing the shaft, the lateral third of the circumference of the shaft is cut away and reattached distally with a hinge, creating a lateral flap. By closing this flap the hindfoot is gently levered from the varus position into valgus. Ten patients (seven amputations at the Chopart-level, three amputations at the Lisfranc-level) with insensate feet were fitted with this prosthesis at an average of 3 (range 1.5 to 9) months after amputation. The handling, comfort, time of daily use, mobility, correction of malposition and complications were recorded to the latest followup (average 31 months, range 24 to 37 months after amputation).
Eight patients evaluated the handling as easy, two as difficult. No patient felt discomfort in the prosthesis. The average time of daily use was 12 hours, and all patients were able to walk. All varus deformities were corrected in the prosthesis. Sagittal alignment was kept neutral. Complications were two minor skin lesions and one small ulcer, all of which responded to conservative treatment, and one ulcer healed after debridement and lengthening of the Achilles tendon.
The "flap-shaft" prosthesis is a valuable option for primary or secondary prosthetic fitting of Chopart-level and Lisfranc-level amputees with insensate feet and flexible equinus and varus deformity at risk for recurrent ulceration. It provided safe and sufficient correction of malpositions and enabled the patients to walk as much as their general condition permitted.
在Chopart和Lisfranc截肢术中，肌腱不可避免地离断以及前足缺失会导致残足出现马蹄内翻畸形。在感觉缺失的足部，这些畸形会导致角化性病变和溃疡。目前可用的假肢无法安全地抵消变形力及由此产生的并发症。
研发了一种新的膝下假肢，它结合了柔软的接受腔和刚性的杆体。取模时足部处于矫正位置。杆体制成后，将杆体圆周的外侧三分之一切除，并通过铰链在远端重新连接，形成一个外侧皮瓣。通过闭合这个皮瓣，后足被轻轻地从内翻位置矫正到外翻位置。10例足部感觉缺失的患者（7例Chopart平面截肢，3例Lisfranc平面截肢）在截肢后平均3个月（范围1.5至9个月）安装了这种假肢。记录了最新随访时（截肢后平均31个月，范围24至37个月）的操作便利性、舒适度、每日使用时间、活动能力、畸形矫正情况及并发症。
8例患者认为操作简便，2例认为操作困难。没有患者感到假肢不适。平均每日使用时间为12小时，所有患者都能够行走。假肢内所有内翻畸形均得到矫正。矢状面排列保持中立。并发症包括2处轻微皮肤病变和1处小溃疡，所有这些均对保守治疗有反应，1处溃疡在清创和跟腱延长后愈合。
“皮瓣 - 杆体”假肢是Chopart平面和Lisfranc平面截肢且足部感觉缺失、存在马蹄内翻畸形且有复发性溃疡风险的患者进行初次或二次假肢装配的一个有价值的选择。它能安全、充分地矫正畸形，使患者能够在其身体状况允许的情况下尽可能多地行走。
