尺骨鹰嘴骨折不同程度骨量丢失对肘关节稳定性的影响

目的 探讨尺骨鹰嘴骨折时不同程度骨量丢失对肘关节稳定性的影响.方法 取10具20侧男性新鲜上技标本,在距尺骨鹰嘴尖部10 mm处向远端截骨,制备鹰嘴中部不同程度骨缺损,即骨量丢失模型,截骨分为4组,每组5侧上肢标本,即尺骨鹰嘴完整组、截除3mm组、截除6mm组、截除9 mm组,骨折断端予张力带内固定后,测量每组肘关节屈伸活动范围变化及肘关节在屈曲30°、60°、90°、120°时,前臂施加1.96 N·m扭距,肘关节内外翻角度的变化,同时观察肱尺关节关系.结果当尺骨鹰嘴截骨至3 mm时,肘关节的伸直活动开始受限;当尺骨鹰嘴截骨至6 mm时,CB片示肱尺关节出现不服贴,鹰嘴尖紧贴滑车关节面,滑车与鹰嘴之间间隙增大,肘关节的伸直活动明显受限;当尺骨鹰嘴截骨至9mm时,CR片示肘关节明显处于半脱位,滑车切迹的弧度基本消失.肘关节屈曲30°、60°、90°时,随截骨量增大肘外翻角度增大,当截骨量达到6 mm时外翻角度明显增大,差异有统计学意义(P＜0.05).而肘关节屈曲30°、60°、90°、120°时,内翻角度组间差异无统计学意义(P＞0.05).结论 尺骨鹰嘴中部截骨缩短达到6mm时,滑车切迹弧度发生改变,出现肘关节不稳定.临床对于尺骨鹰嘴中部粉碎性骨折如短缩不超过6 mm可单纯固定,否则应考虑原位植骨内固定.     

尺骨冠突骨折对肘关节稳定性的影响

目的探讨不同程度尺骨冠突骨折对肘关节稳定性的影响。方法采用11具22侧新鲜成人尸体的上肢标本,在6侧上肢上测量尺骨冠突的高度,滑车切迹开口纵径,开角的大小以及冠突1/2高度处在冠状面的宽度,矢状面的厚度等。在分别距尺骨冠突尖2mm、冠突高1/4处、冠突高1/2处、冠突高3/4处和冠突基底处截骨,测量肘关节的伸屈活动度及稳定性。另16侧上肢随机分成两组,在冠突高1/2处截骨行内固定,一组不修复尺侧副韧带前束,而另一组修复尺侧副韧带前束,分别观测伸屈时肘关节外翻角度的变化。结果尺骨冠突截骨高度不超过冠突高的1/4时,肘关节伸屈稳定性不受影响;当截骨高度达冠突高的1/2以上时,肘关节稳定性明显受影响,活动时会出现半脱位或后脱位,同时尺侧副韧带前束受损;而当尺骨冠突截骨再复位内固定后,尺侧副韧带前束断裂不修复与修复之间,肘关节屈曲0°、30°、60°、90°和120°其外翻角度有显著增加(P<0.05),肘关节不稳定,证实尺侧副韧带前束在抗外翻应力方面有重要作用。结论尺骨冠突骨折不超过冠突原高度的1/4时,对肘关节稳定性无显著影响,有手术摘除碎骨片不会影响肘关节功能;当尺骨冠突骨折超过原高度的1/2合并有尺侧副韧带前束损伤时,会明显影响肘关节稳定性,在行复位内固定的同时,应修补或重建韧带以稳定     

肘关节尺侧逼韧带的生物力学评价

肘关节尺侧副韧带由前束和后束组成犤１－４犦，其前束被认为是肘关节抗外翻应力的主要结构犤４－７犦，前束损伤将导致肘关节轻度的外翻不稳定及在做投掷动作时肘内侧疼痛。前束又可分为前部和后部犤３，４，８犦。肘关节尺侧副韧带各组成部分在维持肘关节稳定中的生物力学作用目前尚不明确。本实验通过系统的解剖学和生物力学研究，探讨肘关节尺侧副韧带各组成部分在肘关节运动时的生物力学作用，研究肘关节外翻不稳定的发生机制。材料与方法冷冻保存的新鲜成人上肢标本２０具，室温下解冻，制成肘关节“骨－韧带”标本。在距关节面远、近…     

肘关节创伤中内侧副韧带重建必要性之辩

肘关节创伤中内侧副韧带结构损伤较为常见。内侧副韧带复合体分为前、斜、后三束,前束起始于肱骨内侧髁的前下部,止于尺骨冠突的前内缘。斜束紧贴尺骨面,连续前束和后束在尺骨上的止点。后束起于肱骨内侧髁的内下缘,止于尺骨鹰嘴近中1/3内缘。2009年肘关节恐怖三联征治疗指南中治疗肘关节恐怖三联征应常规行外侧副韧带修复,是否需要修复内侧结构（包括内侧副韧带及共同屈肌复合体）是争论焦点。肘关节恐怖三联征损伤不一定都损伤外侧副韧带,也有可能仅损伤内侧副韧带。内侧副韧带前束在抗外翻应力方面起主要作用,是肘关节内侧稳定的主要结构。内侧副韧带前束是肘关节韧带中最坚韧的一束,从肘关节伸直到屈曲60°的过程中呈紧张状态;屈曲超过60°,在抗外翻应力方面前、后束共同起作用。Eygendaal等通过长期随访发现,大部分内侧副韧带损伤的患者都存在肘关节外翻不稳定相关性疾病,如关节退化、异位骨化、疼痛等,因此认为应该对存在内侧副韧带损伤的患者进行MCL修复。Jeong等对13例肘关节恐怖三联征患者在对修复肘关节外侧的同时,常规通过外侧入路或内侧入路修复内侧受损结构,平均随访25个月,Mayo评分为平均95分（85~100分）,获优10例,良3例。他们认为采用内、外侧入路修复所有内、外侧损伤组织可达到满意的临床及影像学效果,建议对于肘关节恐怖三联征患者应常规修复关节内侧结构。Toros等认为一般仅对外侧结构修复完毕后仍存在持续性肘关节屈伸不稳定或明显外翻不稳定的患者,应采取内侧入路修复内侧结构。     

肘关节尺侧副韧带的生物力学评价

肘关节尺侧副韧带由前束和后束组成[1-4],其前束被认为是肘关节抗外翻应力的主要结构[4-7],前束损伤将导致肘关节轻度的外翻不稳定及在做投掷动作时肘内侧疼痛.前束又可分为前部和后部[3,4,8].肘关节尺侧副韧带各组成部分在维持肘关节稳定中的生物力学作用目前尚不明确.本实验通过系统的解剖学和生物力学研究,探讨肘关节尺侧副韧带各组成部分在肘关节运动时的生物力学作用,研究肘关节外翻不稳定的发生机制.     

肘关节副韧带的形态结构特点及功能分析

目的 搪塞肘关节副韧带的形态结构特点在不同屈曲角度时的形态变化规律。方法 在５４侧成人肘关节标本上解剖、观察肘关节副韧带的组成、形态特点及肘关节不同屈曲角度时副带的形态变化。结果 （１）尺侧副韧带前束起于肱骨内上髁的前下方,止于尺骨冠突内小结节;后束起于肱骨内上髁的内下方,止于尺骨鹰嘴内侧的骨面;（２）桡侧副韧带直于肱骨个上髁的外下方,其纤维部分止于环状韧带,部分止于尺骨冠突的外下方;桡侧副韧带     

尺骨鹰嘴粉碎性骨折短缩固定后的肘关节功能研究

目的尺骨鹰嘴粉碎性骨折后易出现骨折端短缩,导致肘关节功能障碍。通过尸体解剖实验,以不同的截骨厚度和方向来模拟骨折后尺骨鹰嘴短缩、变小等局部形态变化,探讨其对肘关节屈伸活动的影响。方法取3具新鲜成年男性尸体的双侧上肢标本,在距尺骨鹰嘴顶点25mm处行水平截骨并用两枚螺钉临时固定,再依次截骨1mm、3mm、5mm,测量肘关节的屈伸活动度。然后将标本分成两组,一组继续水平截骨至7mm和8mm,测量肘关节的屈伸活动度;而另一组则依次以5mm、7mm为水平截骨距离,分别采用楔形截骨的方法,观察肘关节屈伸功能的改善度。结果尺骨鹰嘴短缩3mm后原位固定,肘关节屈伸活动无明显受限;若尺骨鹰嘴缺损达5mm,则会因尺骨滑车切迹关节面弧度的改变而导致肘关节的伸直明显受限,将截骨处远端背侧的骨皮质去除3mm行楔形截骨后再固定,肘关节伸直功能还可以恢复正常。但若尺骨鹰嘴短缩达7mm和8mm时,肘关节的伸直受限分别为47°和35°,楔形截骨后也会出现肘关节不稳定。结论如尺骨鹰嘴粉碎性骨折所致的短缩在3mm之内,可行单纯固定,肘关节屈伸功能无明显受限;若短缩在3～5mm之间,仍可以采用短缩原位固定的方法,但应将尺骨鹰嘴后倾固定,使滑车切迹尽量保持原有的弧度;而若短缩达到7～8mm,即使保持滑车切迹的弧度,肘关节伸直仍明     

桡骨头切除对肘关节稳定性影响的生物力学研究

目的：探讨桡骨头粉碎性骨折不同治疗方法对肘关节稳定性的影响。方法：将10个尸体标本，分别测定在其它组织无损伤时，肘内侧副韧带切断时，肘内侧副韧带和前臂骨间膜均切断时的力－位移曲线（纵向位移）及肘外翻角。结果：肘内侧副韧带切断时的纵向位移及肘外翻角均大于其它组织无损伤时；肘内侧副韧带和前臂骨间膜均切断时的纵向位移及肘外翻角均大于其它组织无损伤时和肘内侧副韧带切断时，两两间比较均有显著性差异（P＜0．001）。结论：在其它组织无损伤时，单纯桡骨头切除是安全的；合并肘内侧副韧带损伤时，可在有效修补韧带的同时作单纯头切除，必要时行假体置换；合并肘内侧副韧带和前臂骨间膜均损伤时，最好作假体置换。     

尺骨冠突前内侧面骨折研究进展

尺骨冠突在肘关节稳定性中的作用越来越受到重视.解剖研究发现约有58%的尺骨冠突前内侧面没有尺骨干骺端和骨干的支持,受到内翻应力极易发生骨折.肘关节内翻、后内侧旋转损伤可引起冠突前内侧面骨折,常伴有肱尺关节半脱位和外侧副韧带起点处撕脱损伤.肘内侧副韧带前束不易受损.常表现为完整的内侧副韧带前束连带着前内侧面骨折块,一般骨折块较大,可引起肘关节内侧不稳.目前此类骨折以手术治疗为主,可先行肘内侧入路暴露骨折处,直视下解剖复位和牢固固定骨折块,再通过肘后外侧入路修复受损的外侧副韧带.重建冠突稳定性和修复受损的外侧副韧带可使肘关节获得稳定,并达到满意的治疗效果.但该法主要适用于单纯冠突前内侧面骨折,如果骨折是肘部复杂骨折脱位的一部分,可根据骨折类型选择合适的手术入路和固定方法.     

慢性肘关节不稳定的手术治疗

目的探讨慢性肘关节不稳定的原因和治疗方法。方法1998年8月～2002年8月,12例慢性肘关节不稳定患者完善体格检查及影像学检查,结合术中探查,分析其原因；采用内、外侧入路分别或同时修复与重建肘关节尺、桡侧副韧带,总结疗效。桡侧副韧带的修复方法是将指总伸肌腱的外侧半劈开向外侧转位,将外侧关节囊重叠缝合数针后,在尺骨冠突外侧尺侧副韧带前束的起止点处钻骨孔,将转位的肌腱穿过骨孔后缝合重建桡侧副韧带前束,然后将伸肌总腱缝合。尺侧副韧带的修复是将屈肌总腱劈为两半,取外侧半,保留其在肱骨髁的止点,从尺骨冠突内侧钻骨孔后将肌腱条穿过骨洞后反折缝合固定于尺侧副韧带前束的止点处,将后束增生瘢痕尽量切除,缝合关节囊及屈肌总腱。结果所有患者随访2～6年,平均3年。肘关节未发生复发性脱位,应力外翻试验阴性,肘关节外侧及后外侧轴移试验(PST)阴性,肘部无疼痛；活动范尉：平均屈伸0～135°,前臂旋转：平均旋前85°、旋后80°,患者均恢复正常生活及工作。根据中华医学会手外科学会(2000年,无锡)全国上肢功能评定标准进行肘关节功能评价,本组优8例,良4例,优良率为100%。结论慢性肘关节不稳定主要原因是肘关节侧副韧带损伤；采用手术重建肘关节侧副韧带治疗慢性肘关节不稳定效果可靠。     

Medial collateral ligament strain with partial posteromedial olecranon resection. A biomechanical study

BACKGROUND: Partial resection of the posteromedial aspect of the olecranon in the treatment of valgus extension impingement osteophytosis is a well-described technique. It has been hypothesized that removal of the normal olecranon process, beyond the osteophytic margin, increases the strain in the anterior bundle of the medial collateral ligament. METHODS: We used an electromagnetic tracking device to investigate the strain in the anterior bundle of the medial collateral ligament as a function of increasing applied torque and posteromedial resections of the olecranon in seven cadaveric elbows. Applied torques under valgus stress consisted of hand weight, hand weight plus 1.75 Nm, and hand weight plus 3.5 Nm. Resections were conducted in sequential 3-mm increments, from 0 to 9 mm. We measured changes in the length of the anterior and posterior bands of the anterior bundle of the medial collateral ligament with strain gauges. The strains of the two bands were averaged, and the average was reported. RESULTS: The strain in the anterior bundle of the medial collateral ligament was found to increase with increasing flexion angle, valgus torque, and olecranon resection beyond 3 mm. In two elbows, the anterior bundle of the medial collateral ligament ruptured during testing following the 9-mm resection. There was a significant difference between the strain following the 6-mm resection and that following the 3-mm resection at 110 degrees of flexion with 3.5 Nm of added torque (p = 0.004). CONCLUSIONS: In this in vitro cadaver study, an increase in flexion angle, an increase in valgus torque, and resection of > or =6 mm led to an increase in strain in the anterior bundle of the medial collateral ligament. The non-uniform change in strain related to 3 mm of resection suggests that resections of the posteromedial aspect of the olecranon of >3 mm may jeopardize the function of the anterior bundle.     

Partial posteromedial olecranon resection: a kinematic study

BACKGROUND: The posteromedial aspect of the olecranon process is a site of impingement and subsequent osteophyte development in throwing athletes. Treatment with débridement, with resection of osteophytes and varying amounts of normal olecranon bone, is common. We found no reports in the literature concerning the effects of resecting different amounts of normal bone from the posteromedial aspect of the olecranon. We hypothesized that excessive resection would increasingly alter elbow kinematics and that an optimum amount of olecranon resection could be identified. METHODS: We investigated the kinematic effects of increasing valgus and varus torques and posteromedial olecranon resections, in twelve cadaveric elbows, with use of an electromagnetic tracking device. Two valgus and two varus torques were applied, and three sequential resections were performed in 3-mm steps from 0 mm to 9 mm. Statistical analyses included paired t tests, 95% confidence intervals, a one-factor analysis of variance with repeated measures, and a post hoc test when significance was established. RESULTS: Sequential partial resection of the posteromedial aspect of the olecranon resulted in stepwise increases in valgus angulation with valgus torque. Clear differences were seen at each level of resection. A pattern of increased valgus angulation also was seen in association with increased valgus torque. Increased valgus torque resulted in a trend toward increased axial internal rotation of the ulna, whereas increased osseous resection resulted in a decrease in the absolute degree of internal rotation or, in some specimens, increased external rotation. CONCLUSIONS: Although no single critical amount of olecranon resection was identified, valgus angulation of the elbow increased in association with all resections, with a marked increase occurring in association with a 9-mm resection. Our findings challenge the rationale of removing any amount of normal olecranon bone in throwing athletes as doing so may increase strain on the medial collateral ligament. The implications for the professional throwing athlete are important, and we recommend that bone removal from the olecranon be limited to osteophytes, without the removal of normal bone.     

Posterior olecranon resection and ulnar collateral ligament strain

Valgus extension overload is well described in the throwing athlete. The surgical treatment involves posterior olecranon osteophyte resection. It is not known how much of the posterior olecranon can be resected before increased stress is placed on the ulnar collateral ligament. Ten cadaveric arms underwent posterior olecranon resection in 4-mm increments. After each bone resection, three different valgus loads were applied to the elbow at 70 degrees and 90 degrees of flexion. Ulnar collateral ligament strain significantly increased with each load. Significantly more strain occurred on the ulnar collateral ligament at 90 degrees compared with 70 degrees of elbow flexion. This difference may be the result of the relative importance of the ulnar collateral ligament and the posterior olecranon at different positions of elbow flexion. The strain on the ulnar collateral ligament was slightly higher after the 8-mm and 12-mm cuts but not statistically significant. This study suggests that at moderate quasistatic valgus loads, ulnar collateral ligament strain is not significantly increased with posterior olecranon resection.     

Contribution of monoblock and bipolar radial head prostheses to valgus stability of the elbow.

BACKGROUND: The purpose of this study was to evaluate the stabilizing effect of radial head replacement in cadaver elbows with a deficient medial collateral ligament. METHODS: Passive elbow flexion with the forearm in neutral rotation and in 80 degrees of pronation and supination was performed under valgus and varus loads (1) in intact elbows, (2) after a surgical approach (lateral epicondylar osteotomy of the distal part of the humerus), (3) after release of the anterior bundle of the medial collateral ligament, (4) after release of the anterior bundle of the medial collateral ligament and resection of the radial head, and (5) after subsequent replacement of the radial head with each of three different types of radial head prostheses (a Wright monoblock titanium implant, a KPS bipolar Vitallium [cobalt-chromium]-polyethylene implant, and a Judet bipolar Vitallium-polyethylene-Vitallium implant) in the same cadaver elbow. Total valgus elbow laxity was quantified with use of an electromagnetic tracking device. RESULTS: The mean valgus laxity changed significantly (p < 0.001) as a factor of constraint alteration. The greatest laxity was observed after release of the medial collateral ligament together with resection of the radial head (11.1 degrees +/- 5.6 degrees). Less laxity was seen following release of the medial collateral ligament alone (6.8 degrees +/- 3.4 degrees), and the least laxity was seen in the intact state (3.4 degrees +/- 1.6 degrees). Forearm rotation had a significant effect (p = 0.003) on valgus laxity throughout the range of flexion. The laxity was always greater in pronation than it was in neutral rotation or in supination. The mean valgus laxity values for the elbows with a deficient medial collateral ligament and an implant were significantly greater than those for the medial collateral ligament-deficient elbows before radial head resection (p < 0.05). The implants all performed similarly except in neutral forearm rotation, in which the elbow laxity associated with the Judet implant was significantly greater than that associated with the other two implants. CONCLUSIONS AND CLINICAL RELEVANCE: This study showed that a bipolar radial head prosthesis can be as effective as a solid monoblock prosthesis in restoring valgus stability in a medial collateral ligament-deficient elbow. However, none of the prostheses functioned as well as the native radial head, suggesting that open reduction and internal fixation to restore radial head anatomy is preferable to replacement when possible.     

Kinematics of partial and total ruptures of the medial collateral ligament of the elbow

In this study the kinematics of partial and total ruptures of the medial collateral ligament of the elbow are investigated. After selective transection of the medial collateral ligament of 8 osteoligamentous intact elbow preparations was performed, 3-dimensional measurements of angular displacement, increase in medial joint opening, and translation of the radial head were examined during application of relevant stress. Increase in joint opening was significant only after complete transection of the anterior part of the medial collateral ligament was performed. The joint opening was detected during valgus and internal rotatory stress only. After partial transection of the anterior bundle of the medial collateral ligament was performed, there was an elbow laxity to valgus and internal rotatory force, which became significant after transection of 100% of the anterior bundle of the medial collateral ligament and was maximum between 70 degrees to 90 degrees of flexion. No radial head movement was seen after partial or total transection of the anterior bundle of the medial collateral ligament was performed. In conclusion, this study indicates that valgus or internal rotatory elbow instability should be evaluated at 70 degrees to 90 degrees of flexion. Detection of partial ruptures in the anterior bundle of the medial collateral ligament based on medial joint opening and increased valgus movement is impossible.     

Metallic radial head arthroplasty improves valgus stability of the elbow

The stabilizing influence of radial head arthroplasty was studied in eight medial collateral ligament deficient anatomic specimen elbows. An elbow testing apparatus, which used computer controlled pneumatic actuators to apply tendon loading, was used to simulate active elbow flexion. The motion pathways of the elbow were measured using an electromagnetic tracking device, with the forearm in supination and pronation. As a measure of stability, the maximum varus to valgus laxity over the range of elbow flexion was determined from the difference between varus and valgus gravity loaded motion pathways. After transection of the medial collateral ligament, the radial head was excised and replaced with either a silicone or one of three metallic radial head prostheses. Medial collateral ligament transection caused a significant increase in the maximum varus to valgus laxity to 18.0 degrees +/- 3.2 degrees. After radial head excision, this laxity increased to 35.6 degrees +/- 10.3 degrees. The silicone implant conferred no increase in elbow stability, with a maximum varus to valgus laxity of 32.5 degrees +/- 15.5 degrees. All three metallic implants improved the valgus stability of the medial collateral ligament deficient elbow, providing stability similar to the intact radial head. The use of silicone arthroplasty to replace the radial head in the medial collateral ligament deficient elbow must be questioned. Metallic radial head arthroplasty provides improved valgus stability, approaching that of an intact radial head.     

Stabilizers of capitellocondylar total elbow arthroplasty

The contribution of the medial and lateral collateral ligaments (MCL, LCL) and muscle forces to the kinematics and stability of the capitellocondylar total elbow arthroplasty was investigated in six fresh cadaveric elbows. The three-dimensional orientation of the ulna relative to the humerus was monitored with the use of an electromagnetic tracking device in neutral, valgus, and varus stress positions with (1) the ligaments intact, (2) LCL insufficiency obtained by osteotomizing the lateral epicondyle, (3) partial MCL insufficiency obtained by sectioning either the anterior or posterior bundle of the MCL, and (4) complete MCL insufficiency. Simulated muscle forces were applied as follows: (1) no load, (2) 1 kg each to the biceps and the brachialis and 2 kg to the triceps, and (3) 2 kg to the biceps and the brachialis and 4 kg to the triceps. The laxity was defined as the difference in valgus/varus orientation of the ulna in the valgus and varus stress positions. The laxity at 40°, 75°, and 110° elbow flexion was analyzed. The greatest laxity occurred with LCL insufficiency (40.7° ± 11.6°, average at three flexion angles) followed by that with MCL insufficiency (15.7° ± 9.9°), both of which were significantly larger than laxity with the intact ligaments (5.6° ± 2.5°). The laxity with the anterior bundle sectioned (12.0° ± 8.1°) was significantly greater than with the posterior bundle sectioned (3.3° ± 3.6°); thus the contribution of anterior bundle to stability was four times that of posterior bundle. Stabilizing effect of muscle loading was small in elbows with intact ligaments, whereas it was large with LCL or MCL insufficiency. Based on these data, we can see that the integrity of both the MCL and LCL is essential to maintain stability of this total elbow, the anterior bundle is a more important stabilizer than the posterior bundle, and the collateral ligaments seem to be the primary stabilizer and the musculature seems to be the secondary stabilizer. Careful implantation technique to preserve the collateral ligaments is required to obtain postoperative stability of this arthroplasty. Otherwise, routine exposure of the MCL and repair or reinforcement of the MCL, if deficient, may need to be considered during surgery.     

肘关节内侧副韧带前束重建的生物力学研究

目的通过测量肘关节内侧副韧带(medial collateral ligament,MCL)前束生物力学指标,探讨前束完整及重建后对肘关节外翻稳定性的影响,评价采用人工肌腱、界面螺钉重建MCL前束疗效。方法成人完整上肢标本12具,男8具,女4具;左、右侧各6具;制成肘关节"骨-韧带"标本。采用生物力学及压敏胶片测量方法,分别测量MCL前束完整(对照组)及使用人工肌腱、界面螺钉重建后(实验组)肘关节屈曲0、30、60、90°时关节外翻松弛度、肱尺关节受力面积及肘关节内压强。结果两组在肘关节不同屈曲角度下,组内及组间关节松弛度比较,差异均无统计学意义(P>0.05)。除肘关节屈曲0°时两组肘关节压强小于其余屈曲角度(P<0.05),及对照组小于实验组(P<0.05)外,两组其余各角度组内及组间比较差异均无统计学意义(P>0.05)。除对照组内肘关节屈曲0°时肱尺关节受力面积大于其余屈曲角度(P<0.05)外,两组其余各角度组内及组间比较差异均无统计学意义(P>0.05)。结论 MCL前束对维持肘关节外翻稳定性具有重要意义,金属界面螺钉加人工肌腱重建后可即刻恢复内侧稳定。     

Elbow joint instability: A kinematic model

The effect of simultaneous ulnar and radial collateral ligament division on the kinematics of the elbow joint is studied in a cadaveric model. Severance of the anterior part of the ulnar collateral ligament and the annular ligament led to significant elbow joint instability in valgus and varus stress and in forced external and internal rotation. The mean maximum laxity in valgus stress and forced external rotation were 5.7° and 13.2°. The forearms of the elbow joint specimens were transfixed in maximum pronation. During valgus and varus stress the corresponding spontaneous ulnar rotation of the specimens was recorded. The reproducibility of the instability pattern suggests that this model is suitable for evaluating stabilizing procedures aimed at correction of elbow joint instability before these procedures are introduced into patient care.