股骨远端骨折微创内固定系统临床应用

目的 探讨应用股骨远端微创内固定系统（less invasive stabilization system—distal femur，LISS—DF）治疗33A3、33C2和33C3型骨折的疗效与影响因素。方法2004年8月～2005年12月，应用LISS—DF治疗26例股骨远端骨折。男15例，女11例；年龄32～72岁，平均55岁。33A3型9例，33C2型11例、33C3型6例。左侧16例，右侧10例。交通伤12例，高处坠落伤9例，压砸伤5例。开放性骨折3例，其中Gustilo Ⅰ型2例，Gustilo ⅡA型1例。受伤至手术时间6h～16d，平均4d。33C2、C3型骨折17例采用髌骨旁外侧切口，结合经关节逆行插入钢板接骨技术插入LISS—DF固定；33A3型骨折9例采用间接复位方法，经皮小切口将自攻或自钻型锁定头螺钉与LISS—DF钢板单皮质锁定。结果术后患者获随访12～26个月，平均14．5个月。1例出现骨延迟愈合，最终达骨性愈合；X线片示骨折愈合时间11～36周，平均16．1周；完全负重时间13～26周，平均17．6周。1例发生切口浅部感染，经换药后愈合；5例因股骨远端外侧严重疼痛于术后6～13个月行内固定物拔除术。均无深部感染、内固定松动、脱出及断裂发生。术后根据Rasmussen骨折复位标准评分12～19分，平均17．6分，其中优16例，良9例，可1例。按照Merchant膝关节功能评分：优13例，良11例，可2例，优良率为92．3％。结论LISS系统设计符合生物学固定原理，对股骨远端A3、C2和C3型骨折提供了一种新的有效内固定方法，但在临床应用中要严格掌握手术指征及操作规程。

TREATMENT OF DISTAL FEMUR FRACTURE BY LESS INVASIVE STABILIZATION SYSTEM-DISTAL FEMUR

OBJECTIVE: To investigate the therapeutic effects and the related factors during operation of the less invasive stabilization system-distal femur (LISS-DF)for Types 33A3, C2 and C3 fractures classfied on the criteria by Association of Orthopedics (AO). METHODS: From August 2004 to December 2005, 26 patients with distal femoral fractures were surgically treated by LISS-DF, including 9 patients with Type 33A3, 11 with Type 33C2, and 6 with Type 33C3. There were 15 males and 11 females, aged 32-72 years (average, 55 years). The fractures occurred on the left side in 16 patients and on the right side in 10 patients. The fractures resulted from a road traffic accident in 12 patients, a fall from the height in 9, and a crush injury in 5. Of the 26 patients, 3 had an open fracture (2 Gustilo Type I, 1 Gustilo Type II A), with the mean time between the injury and the operation of 4 days (range, 6 h-16 d). The operation through a lateral para-patellar incision and a trans-articular retrograde plate of osteosynthesis (TARPO) was performed on 17 patients for Type 33C2 and 33C3 fracture of the distal femur. The locking head screw (LHS) insertion through the stab incisions and monocortical fixation was performed on 9 patients for Type 33A3 fracture. RESULTS: The follow-up of all the patients for 12-26 months averaged 14.5 months revealed that the bone union was completed in all the 26 patients, 1 of whom had a delayed bone union. The X-ray films showed that the time for the bone union was 11-36 weeks averaged 16.1 weeks, and the time for the full weight loading was 13-26 weeks averaged 17.6 weeks. Superficial infection developed in 1 patient, and the infection was cured after the dressing changes. The internal fixator attachment was performed on 5 patients 6-13 months after operation, who had a serious pain in the lateral part of the distal femur. No deep infection, loosening of the internal fixation, breakage or failure of the implants was found in all the patients. Evaluated by the Merchant score system for the knee joint, of the 26 patients 13 achieved an excellent result, 11 achieved a good result, and 2 achieved a fair result, with 92.3% excellent and good results. Based on the Rasmussen criteria for the fracture reduction, the 26 patients had standard scores of 12-19 with an average of 17.6; of the 26 patients, 16 had an excellent result, 9 had a good result, and 1 had a fair result. CONCLUSION: The LISS is consistent with the principles of biological osteosynthesis on the design, and the system offers a new and effective internal fixation method for treatment of AO Types A3, C2 and C3 fractures. However, its operation indications and operating instructions should be strictly followed.