三角韧带与下胫腓联合韧带对踝关节稳定的生物力学影响

目的探讨三角韧带与下胫腓联合对踝关节稳定性的生物力学影响。方法采用6例新鲜踝关节标本,常规制成骨-韧带模型(标本可重复利用)。分为:A组:踝关节各韧带均完整;B组:三角韧带离断,下胫腓联合完整;C组:下胫腓联合离断,三角韧带完整;D组:下胫腓联合及三角韧带均离断;E组:锚钉修复三角韧带、螺钉固定下胫腓联合韧带组。对标本施加600 N轴向加载。分别测量三种体位(中立位、背伸10°位、跖屈20°位)在各种状态下胫距关节的接触面积、接触压力、压应力分布等变化。对比分析三角韧带及下胫腓联合韧带修复前后对踝关节稳定的作用。结果在三种体位下均可发现,随着下胫腓联合及三角韧带的离断,胫距关节接触面积逐渐减小,接触压力逐渐增大,与正常A组对比差异有统计学意义(P<0.05),压应力分布逐渐集中并有向外侧移位趋势;三角韧带与下胫腓联合修复前后的胫距关节的接触面积、接触压力等差异有统计学意义(P<0.05);修复后的胫距关节接触面积增大、接触压力减少,与正常组A组对比差异无统计学意义(P>0.05),压应力分布分散。结论三角韧带与下胫腓联合断裂后,距骨发生移位,胫距关节面接触面积、接触压力及压应力分布发生剧烈变化。目前骨锚钉修复三角韧带、螺钉固定下胫腓联合能获得即刻稳定,且其生物力学强度与正常组相似,推荐对三角韧带伴下胫腓联合损伤者行手术治疗以恢复其正常解剖关系。     

Weber B型和C型踝关节骨折术中下胫腓联合稳定性的评价

目的 探讨Weber B型和C型踝关节骨折术中下胫腓联合稳定性的评价方法及效果. 方法 2007年3月至2009年3月,收治231例Weber B型和C型踝关节骨折患者,术中踝关节骨折的骨性结构恢复后,在C型臂X线透视下通过腓骨外拉应力试验来检查下胫腓联合的稳定性. 结果 Weber B型踝关节骨折145例,42例(28.9%)出现下胫腓联合不稳定;C型踝关节骨折86例,62例(72.1%)出现下胫腓联合不稳定.下胫腓联合不稳定的踝关节骨折均进行了下胫腓联合固定. 结论 Weber B型和C型踝关节骨折在骨性结构被恢复后,下胫腓联合不稳定仍然有较高的发生率.术中通过C型臂X线透视下腓骨外拉应力试验能简单有效地对下胫腓联合的稳定性进行评价,可根据其稳定性来确定是否行下胫腓联合固定.     

Weber B型和C型踝关节骨折术中下胫腓联合稳定性的评价

目的 探讨Weber B型和C型踝关节骨折术中下胫腓联合稳定性的评价方法及效果. 方法 2007年3月至2009年3月,收治231例Weber B型和C型踝关节骨折患者,术中踝关节骨折的骨性结构恢复后,在C型臂X线透视下通过腓骨外拉应力试验来检查下胫腓联合的稳定性. 结果 Weber B型踝关节骨折145例,42例(28.9%)出现下胫腓联合不稳定;C型踝关节骨折86例,62例(72.1%)出现下胫腓联合不稳定.下胫腓联合不稳定的踝关节骨折均进行了下胫腓联合固定. 结论 Weber B型和C型踝关节骨折在骨性结构被恢复后,下胫腓联合不稳定仍然有较高的发生率.术中通过C型臂X线透视下腓骨外拉应力试验能简单有效地对下胫腓联合的稳定性进行评价,可根据其稳定性来确定是否行下胫腓联合固定.     

Evaluation of the syndesmotic screw in low Weber C ankle fractures

OBJECTIVE: To determine the functional and radiographic outcome of low Weber C ankle fractures and to evaluate the contribution of the syndesmotic screw in their outcome. DESIGN: Prospective evaluation of a consecutive series. SETTING: Level I trauma center. PATIENTS: Forty-five patients divided into two groups matched for age, sex, and severity of injury. Twenty-six patients were treated with open reduction, internal fixation, and a supplemental syndesmotic screw, and nineteen patients were treated without a syndesmotic screw. Minimum time to follow-up was three years. METHODS: A subjective, objective, and radiographic ankle scoring system was used. Logistical regression analysis was performed to determine whether the presence or absence of a syndesmotic screw was a predictor of a poor outcome. The likelihood ratio test was used to evaluate the significance of each variable in both univariate and multivariate analyses. RESULTS: There was no statistically significant difference between either group, either using subjective outcome criteria (p = 0.86) or in ankle range of motion (p = 0.94). Logistical regression analysis indicated that fracture dislocation could be used as a predictor of a poor outcome for either group. Inadequate reduction and advancing age were also found to be significant predictors of a poorer outcome regardless of the use of a syndesmotic screw (p = 0.003, p = 0.004). CONCLUSIONS: Judicious fixation of Weber C type injuries within five centimeters of the ankle joint, with or without a syndesmotic screw, gives similar results. Obligatory fixation of these fractures with syndesmotic screws appears to have no benefit and creates the need for an additional procedure.     

A biomechanical evaluation of the tibiofibular and tibiotalar ligaments of the ankle

The purpose of this ex vivo biomechanical study was to determine the strength and stiffness of the anterior and posterior syndesmotic tibiofibular ligaments and the posterior tibiotalar component of the deltoid ligament. Injuries to these ligaments are a prevalent clinical problem, yet little is known about their mechanical behavior. Ten fresh-frozen cadaver lower extremities (average age at death, 72 +/- 8 years) were harvested. The anterior and posterior tibiofibular ligaments and the posterior tibiotalar component of the deltoid were isolated and prepared as bone-ligament-bone complexes for tensile testing to determine strength, stiffness, and mode of failure. The posterior tibiofibular ligament exhibited greater strength, but not significantly so (p < .05), than the anterior tibiofibular ligament and the posterior tibiotalar component of the deltoid ligament. There were no significant differences in stiffness between the three ligaments tested. The dominant mode of failure for the anterior tibiofibular ligament was ligament substance rupture, primarily near its fibular insertion, whereas the failure modes of the posterior tibiofibular ligament were evenly split between substance ruptures and fibular avulsions. The posterior tibiotalar component of the deltoid ligament ruptured most often near the talar insertion. The tibiofibular ligaments showed greater strength than the lateral collateral and deltoid ligaments, as mentioned in literature. The greater strength of the tibiofibular ligaments relative to the lateral collateral and deltoid ligaments suggests that these ligaments play an important role in ankle constraint.     

Proximity of the lateral talar process to the lateral stabilizing ligaments of the ankle and subtalar joint

BACKGROUND: Fractures of the lateral process of the talus have become more frequent as the sport of snowboarding has gained popularity. The anatomy of the ligamentous attachments to the process has been described, but ligament proximity to the lateral talar process has never been specified. The objective of this cadaver study was to measure the proximity of the lateral talar process to the various lateral stabilizing ligaments of the ankle and subtalar joint: the anterior talofibular ligament, lateral talocalcaneal ligament, posterior talofibular ligament, interosseous ligament, cervical ligament, and lateral root of the extensor retinaculum. METHODS: After thawing, all musculotendinous structures from 10 fresh-frozen cadaver lower limbs were carefully removed and the distal fibula was reflected to enable adequate exposure of the lateral talar process and ligamentous attachments. The apex of the lateral process was defined. Subsequently, the distance from the apex to the nearest edge and center of these surrounding ligaments was independently measured by two examiners. RESULTS: The average apex-edge distances were 9.3 mm (posterior talofibular); 8.7 mm (anterior talofibular), 3.4 mm (lateral talocalcaneal), 13.9 mm (interosseous), 19.1 mm (cervical), and 13.0 mm (lateral root of extensor retinaculum). The average apex-center distances for those ligaments found to actually insert on the lateral talar process were 18.0 mm (posterior talofibular), 15.7 mm (anterior talofibular), and 6.2 mm (lateral talocalcaneal). CONCLUSIONS: Contrary to previous reports, our cadaver dissections identified that only three ligaments attach to the lateral process of the talus: lateral talocalcaneal, anterior talofibular, and posterior talofibular. CLINICAL RELEVANCE: Familiarity with these anatomic relationships may help guide the clinical treatment of lateral talar process fractures.     

踝部损伤的下胫腓关节固定

踝部损伤时常发生下胫腓关节分离或下胫腓韧带损伤。1993—2003年，在治疗踝部损伤中共行下胫腓关节固定21例，效果满意，报告如下。     

胫腓钩在伴下胫腓韧带损伤的踝关节骨折脱位中的应用

目的评价胫腓钩治疗伴下胫腓韧带损伤的踝关节骨折的疗效。方法2002年3月～2005年11月,应用胫腓钩治疗伴下胫腓韧带损伤的旋前型踝关节骨折脱位患者18例。根据术前X线片判断下胫腓联合损伤的程度,经术中探查证实；于下胫腓联合平面置钩,钩住腓骨,固定于胫骨上。取内固定的同时取胫腓钩。结果16例患者获得3个月～4年(平均17个月)随访,根据踝关节活动度、疼痛及X线情况评定疗效：优14例,良2例,未发现内固定物松动、断裂现象。结论胫腓钩在治疗合并下胫腓韧带损伤的踝关节骨折脱位中能有效地复位和固定,并能提供下胫腓微动关节的生理功能。     

踝关节骨折伴下胫腓关节分离的治疗

目的 探讨踝关了骨折伴下胫腓关节分离的治疗方法。方法 对２０例踝关节骨折伴下胫腓韧带分离患者按Ｂｏｎｎｉｎ分度法,Ⅱ１２例,Ⅲ度８全和加压松质骨螺钉内固定术,使踝穴结构恢复正常。结果 随访８～１８个月,平均１４．５个月病人踝关节功能恢复正常,优良率达８５％。结论 对踝关节骨折伴下胫腓韧还分离的患者在治疗骨折的同时注意修补下胫腓韧带以恢复正常踝穴结构,避兔创伤生骨关节炎发生。     

The effect of the syndesmotic screw on the extension capacity of the ankle joint

Summary To investigate whether, when inserting a syndesmotic screw, the foot position effects the range of motion in dorsal extension, 16 osteoligamentous lower-leg preparations were studied. The specimens were placed in a test frame where a constant dorsal extension force could be applied to the foot. The dorsal extension capacity was recorded with a syndesmotic screw inserted by a standardized technique in various plantar flexion positions. The dorsal extension capacity decreased by an average of 0.1° for every degree of increase in plantar flexion when the screw was being inserted. There was a correlation between a large decrease in range of motion and a limited dorsal extension capacity to start with. No correlation could be found between a large decrease in range of motion and a large difference in width between the anterior and posterior edges of the talar trochlea. The results suggest that the foot should be in maximal dorsal extension when a syndesmotic screw is inserted in order to decrease the risk of stiffness.     

The effect of the syndesmotic screw on the extension capacity of the ankle joint

To investigate whether, when inserting a syndesmotic screw, the foot position effects the range of motion in dorsal extention, 16 osteoligamentous lower-leg preparations were studied. The specimens were placed in a test frame where a constant dorsal extention force could be applied to the foot. The dorsal extention capacity was recorded with a syndesmotic screw inserted by a standardized technique in various plantar flexion positions. The dorsal extension capacity decreased by an average of 0.1 degree for every degree of increase in plantar flexion when the screw was being inserted. There was a correlation between a large decrease in range of motion and a limited dorsal extension capacity to start with. No correlation could be found between a large decrease in range of motion and a large difference in width between the anterior and posterior edges of the talar trochlea. The results suggest that the foot should be in maximal dorsal extension when a syndesmotic screw is inserted in order to decrease the risk of stiffness.     

急性踝关节骨折伴三角韧带损伤术中诊断及治疗策略

目的探讨丝攻试验对三角韧带损伤的诊断价值,比较跨下胫腓联合螺钉固定与锚钉缝合修复三角韧带的疗效。方法 2011年6月至2013年12月,对我院收治的51例疑有三角韧带损伤的踝关节骨折患者进行丝攻试验,并将阳性患者随机分为锚钉缝合修补三角韧带组(A组)和跨下胫腓联合螺钉固定组(B组)。采用美国足踝骨科学会(AOFAS)踝-后足评分和疼痛视觉模拟评分(VAS)评价术后疗效。结果最终45例患者纳入统计学分析。A组21例,B组24例。A组有19例获得随访,平均随访14个月;B组有23例获得随访,平均随访18个月。末次随访时,A、B组患者均获得骨性愈合。A组AOFAS踝-后足评分和VAS评分分别为(87.50±6.30)分和(1.79±1.47)分,B组AOFAS踝-后足评分和VAS评分分别为(85.20±7.54)分和(1.56±1.20)分。两组AOFAS踝-后足评分和VAS评分差异无统计学意义。B组复位不良率达34.8%,A组仅为5.26%。结论三角韧带的完整性是影响下胫腓联合分离和内侧踝穴增宽的重要因素,修补三角韧带与跨下胫腓联合螺钉固定疗效相当,但其复位不良率低,且无二次取钉及断钉等问题。丝攻试验对于三角韧带损伤诊断和手术效果评估具有重要价值。     

下胫腓联合损伤对踝关节稳定性影响的生物力学研究

[目的]探讨下胫腓联合损伤对踝关节稳定性的生物力学影响。[方法]采用6例新鲜尸体标本,制作踝关节旋前外旋损伤模型,逐步离断下胫腓联合各韧带、骨间膜和三角韧带。对标本进行600 N轴向加载,同时对踝关节施加扭矩为5 Nm的外旋力。测量下胫腓联合不同程度损伤情况下,下胫腓联合的相对位移和踝关节外旋扭转角度。[结果]随着下胫腓联合韧带和三角韧带的序贯性离断,下胫腓联合的远端腓骨相对内外位移、前后位移、腓骨转角以及踝关节扭转角度呈逐渐增加趋势。[结论]下胫腓联合韧带维持踝关节稳定。在旋转稳定性方面,下胫腓后韧带的作用最为突出。下胫腓联合韧带离断后,再离断三角韧带,踝关节的稳定性进一步丢失。     

Injuries of the lateral ligaments of the ankle joint

Summary Between 1980 and 1984, 268 patients with recent ankle ligament ruptures were treated with primary surgical repair at to 2nd Department of Trauma Surgery, University of Vienna. The decision for immediate operative treatment was based on clinical findings as well as on a positive stress roentgenogram. Ligament ruptures were diagnosed if the talar tilt on the injured side exceeded that on the uninjured side by 5° or more or if the ventral subluxability of the talus was more than 5 mm compared with the uninjured side. One hundred twenty-two patients were followed up for 2–6 years after operation; follow-up included physical examination as well as standardized and stress roentgenograms. Good results were obtained in 80% of cases, moderate results in 17%, and poor results in 3%. All of the poor results were due to persistent radiological instability and/or arthrotic joint degeneration. The incidence of infection was 1.5%.     

Anatomy of the ligaments of the upper ankle joint

The ankle joint is stabilized by a specialized system of ligaments. These are the medial and lateral collateral ligaments and the anterior and posterior syndesmoses, the arrangement and orientation of which can only be understood in terms of function. In the vast majority of cases, injury involves the fibular capsuloligamentous apparatus which, according to anatomical and intra-operative findings, exhibits considerable anatomical variability, recognition of which is a prerequisite for the correct diagnosis and therapy of such lesions.     

Tightrope fixation of syndesmotic injuries in Weber C ankle fractures: a multicentre case series

Background

No general consensus has yet been established for the gold standard treatment of ankle syndesmotic complex injuries. Recent literature has documented the success of ankle tightrope fixation for heterogeneous ankle fracture patterns, resulting in syndesmotic complex injuries. We present a multicentre case series assessing the clinical, radiological and functional outcomes of patients with Weber C ankle fractures treated with the Arthrex TightRope^® fixation system.

Method

We performed a retrospective analysis of all adult patients with Weber C ankle fractures who were treated with the Arthrex TightRope^® fixation system at four centres over a 3-year period. All patients were followed up for a mean of 14 months (range 12–26). Outcomes measures were assessed subjectively using functional scores (AOFAS and Olerud and Molander) and objectively using radiological measurements, complication rates and revision surgery rates.

Results

Thirty-six patients met our eligibility criteria. The mean age at operation was 31 years (range 18–65). There were 20 males and 16 females. No patients were lost to follow-up. The ankle tightrope maintained satisfactory reduction in the ankle mortise in 97% of cases. Of these 35 successfully treated cases, no evidence of re-displacement on follow-up radiographs of the syndesmotic complex was observed at an average of 10.8 months (range 6–12). Post-operative mean medial clear space was 3.1 mm, and mean tibio-fibular overlap was 10.1 mm. The mean American Orthopaedic Foot and Ankle Society (AOFAS) score was 88.8 (range 67–98) at a mean follow-up of 14 months (range 12–26). The overall complication rate was 6% (one failure requiring revision surgery and one medial sided skin irritation requiring removal of suture button). No infections or wound complications occurred.

Conclusion

Tightrope fixation is a safe alternative to screw fixation for syndesmotic complex injuries in Weber C ankle fractures. We have shown that it has low complication rates and a high patient satisfaction.

     

The role of a fibular nail in the management of Weber type B ankle fractures in elderly patients with osteoporotic bone--a preliminary report

Fibular nailing was performed in 11 Weber type B ankle fractures in elderly patients (average 67.2 years) with osteoporotic bones between March 1996 and February 2000. All the fractures were displaced with significant talar shift. Nine patients remained under follow-up (average 25.9 months). Results were good and excellent in 88% of cases by the modified Olerud and Molander scoring system. One patient developed post-operative ankle subluxation and required ankle fusion. We feel that fibular nailing is an important tool in managing specific types of ankle fracture.