自体肌腱双骨隧道重建技术修复肘关节后外侧旋转不稳定

Autogenous tendon double bone-tunnel reconstruction technique to repair the posterolateral rotating instability of the elbow

目的 探讨自体肌腱双骨隧道重建桡侧尺副韧带（lateral ulnar collateral ligament,LUCL）治疗肘关节后外侧旋转不稳定（posterolateral rotatory instability,PLRI）的手术疗效。方法 2008年1月至2013年12月成都大学附属医院收治16例LUCL损伤患者,11例用双束编制的掌长肌腱对韧带进行重建,5例用对侧半腱肌肌腱重建LUCL治疗肘关节PLRI,移植肌腱穿过肱骨及尺骨双骨隧道带线锚钉固定。观察术后肘关节活动度、肘关节侧方轴移试验、外翻外旋应力位X线片。结果所有患者均获随访,随访时间1~5年,平均2.5年。患者肘关节活动功能明显改善,主观满意,被动外翻、外旋活动时肘关节完全稳定12例,部分不稳定但较术前明显改善4例,优良率为75%。术后Mayo评分65~100分,平均85分,新鲜损伤患者术后功能明显好于陈旧性损伤患者（P〈0.05）。结论 LUCL是影响肘关节PLRI最主要的结构,采用自体肌腱肱骨及尺骨双骨隧道重建LUCL效果良好。

Background The concept of posterolateral rotatory instability （PLRI）of the elbow was proposed in 1991 by O′Driscoll for the first time.The pathogenic mechanism of PLRI is injury to the radial collateral ligament complex at the elbow,among which the lateral ulnar collateral ligament （LUCL） plays a major role. However, because most physicians know little about the elbow dysfunction caused by such ligament inj ury,missed or delayed diagnosis often prevents timely and effective treatment,leading to seriously impact on the quality of life of patients.Surgical treatment is often very effective,but surgical approaches vary a lot.Rhyou et al established a horizontal bone tunnel cross the humerus for passing through the tendon,but this approach doesn′t allow attachment of the upper end of this ligament on the lateral condyle of the humerus. Sanchez-Sotelo et al. established bone tunnel on ulna and humerus perpendicular to the ligament,and passed longer tendon through the tunnel at an＂8＂shape,which was immobilized by suture knot.This procedure requires that the tendon have to be a long and thin one while problems such as tendon breakage and suture slippage often happen.The way Dehlinger et al.established the bone tunnel was similar to the present study,i.e.,after passing the bone tunnel;the tendon was only fixed to the bone marrow with suture. This method also has the disadvantage of poor stability and delayed functional exercise.This study used autologous tendon and established humerus and ulna double bone tunnel for ligament reconstruction in 16 patients and the treatment effect is reported below.Methods From January 2008 to December 2013,orthopedics division of our hospital admitted and diagnosed 16 cases of elbow LUCL tear with PLRI patients,of which 11 males and 5 females,aged 19-43 years old,average age of 28.8 years old,7 cases of fresh injuries and 9 cases of old injuries,4 cases of simple ulnar coronoid process fracture,3 cases of elbow dislocation,5 cases of coronoid fracture with elbow dislocation,and 4 cases of＂terrible triad inj ury of the elbow＂after internal fixation （all received coronoid fracture internal fixation）.There were two cases of radial head resection,7 patients with varus deformity and 5 cases of varus stress position with visible varus.Valgus stress was shown as widened humeroulnar interval,and positive Lateral Pivot Shift for Elbow test under anesthesia.Elbow MRI of all patients showed radial ulnar collateral ligament inj ury or breakage.Surgical Methods：The patients were in prone position.Modified Kocher approach was used.The origin of the common extensor tendon was released from epicondyle.The proximal and distal origin of LUCL and ulna supinator ridge was prepared.Then the unlar extensor carpi muscle was pulled medially and anconeus muscle pulled laterally.The tear patterns of the LUCL were explored （1 3 cases of distal LUCL inj ury,and 3 cases of proximal LUCL inj ury）.The palmaris longus tendon （alternatively the contralateral semitendinosus tendon）was harvested from volar wrist.The length of graft was about 1 2-1 5 cm.The tendon was fold and prepared with No.1 nonabsorbable suture. A V-shape bone tunnel on lateral humeral epicondyle and the supinator ridge was drilled.A 6-8 mm distance was between the two holes on the ulna and the connecting line between the two holes was in line with the direction of LUCL.The graft was passed through tunnels and sutured by suture anchors.The graft should be tensioned in 30°of flexion and maximal supination.The graft could be further strengthened by LUCL remnant.The coronoid fracture should be reduced and fixed.The stability of elbow was checked.Drainage tube was routinely used.The wound was closed in layers.The elbow was immobilized in neutral rotation and 90°of flexion by plaster cast.Post-operative treatment：rubber drainage tube is removed two days after the surgery based on the status of drainage.Patients are encouraged to get out of bed,and guided to flex and extend fingers.Upper arm muscle painless isometric exercise is started 1 week after the surgery.The plaster cast is removed after 2 weeks.Passive elbow flexion exercise is began and gradually increased the magnitude of passive exercise and the strength of the muscle force training,but active flexion of the elbow should be avoided,heavy lifting,supporting,medial and lateral rotation movements also should be avoided.Active flexion exercise is begun after 3 months,and gradually increased the intensity to reach normal activity level after 6 months.Efficacy evaluation：the Mayo elbow performance index was used to evaluate elbow function.Out total of 100 points,pain accounts for 45 points,mobility for 20 points,stability for 10 points,and daily activities for 25 points,≥90 as excellent,75-89 as good,60-74 as acceptable and 〈60 as poor.Results All patients achieved primary healing of the incision.Hospitalization time ranged 10-17 days,with an average of 14.4 days.All patients are received outpatient follow-up of 1-5 years,with an average follow-up time of 2.5 years. The patients′elbow motion improved significantly,and patients are generally satisfied.There were 1 2 cases of patients achieved total stability at passive valgus and lateral rotation,partially instable but significantly improved after the surgery in 4 cases,with a good to excellent rate of 75%.All the 4 patients with partial instability received LUCL reconstruction with suture anchors using the palmaris longus tendon graft.X-ray film can reflect their slight instability at valgus and lateral rotation stress position.Two of these 4 patients were diagnosed as terrible triad inj ury and received internal fixation plus radial head resection,1 case of old typeⅡ coronoid fracture patient who did not undergo surgery and 1 case of fresh type Ⅲ coronoid fracture patient.Postoperative pain relief, elbow mobility and Mayo scores of the fresh inj ury group were all significantly better than those of the old inj ury group （P〈0.05）.Conclusion Radial ulnar collateral ligament is the main structure to affect elbow PLRI,and use of autologous tendon and humerus and ulna double bone tunnel to reconstruct the radial ulnar collateral ligament achieves good results.