Complications and outcome of four-corner arthrodesis: circular plate fixation versus traditional techniques

PURPOSE: To review the clinical and radiographic results of scaphoid excision and four-corner arthrodesis using a circular plate and screws compared with traditional fusion techniques (wires, staples, screws). METHODS: Fifty-eight patients with four-corner arthrodesis (plate fixation, n = 27; traditional fixation, n = 31) were evaluated for radiographic and clinical success using wrist radiographs and functional assays. Patients were subjectively surveyed using the standardized Disabilities of the Arm, Shoulder, and Hand questionnaire and classification scales for pain and satisfaction. Objective measurements included grip-strength and range-of-motion measurements. RESULTS: Radiographic analysis showed 26% nonunion with loose hardware in the plate group compared with 3% in the traditional group and 22% hardware impingement in the plate group compared with 3% in the traditional group. Clinical evaluation yielded a mean grip strength of 31 kg (70% of opposite side) for plate fixation and 33 kg (79% of opposite side) for traditional fixation. The mean flexion-extension arc was 48% and 50% of the opposite wrist for plate and traditional patients, respectively. The mean adjusted Disabilities of the Arm, Shoulder, and Hand questionnaire scores were 27 out of 100 for plate patients and 8 out of 100 for traditional patients. Pain classification scores showed that only 2 patients in the plate group were pain free whereas there were 8 patients in the traditional group who were pain free. Overall patient satisfaction was 60% for the plate group whereas the traditional patient group reported 100% satisfaction. CONCLUSIONS: The rate of major complications (nonunion or impingement) was much greater with circular plate fixation (48%) versus traditional fixation techniques (6%). With the plate procedure the grip strength and arc of motion decreased approximately 30% and 52%, respectively, compared with decreases of 21% and 50%, respectively, for traditional fusion methods. Additionally, subjective patient dissatisfaction was 40% in the plate group compared with 0% in the traditional group. We postulate that the increased complication and dissatisfaction rates associated with plate fixation may be attributable to possible biomechanical imperfections or increased technical demands with this fusion system.     

头、月、三角、钩骨局限性融合术治疗舟月骨进行性塌陷

目的：介绍治疗伴严重腕痛舟月骨进行性塌陷（scapholunate advanced collapse,SLAC)的新术式。方法：11例均为伴有严重腕痛、握力显著下降、腕关节功能受限的Ⅲ期舟月骨进行性塌陷的患者。入院后均行SLAC腕重建术（头、月、三角、钩骨局限性融合）。结果：术后随访7个月－3年半，以最后1次随访结果为准，优7例，良2例，可1例，差1例。除差的1例外，10例的腕痛完全消失或基本消失，平均握力恢复至健侧的80％，腕关节活动范围为健侧的51％。结论：SLAC腕重建术是治疗Ⅲ期能性舟月骨进行性塌陷的一种可靠的挽救性手术，术后能恢复握力、保留腕关节功能。     

四角融合术后腕关节稳定性的衡量指标

目的提出衡量腕关节四角融合术后融合体稳定性的指标,探讨术后如何改善腕功能。方法12具新鲜尸体前臂标本,男8具,女4具,左右各6肢,模拟行四角融合术后,固定于腕关节动力学测试仪上,模拟腕关节的掌屈、背伸、尺倾、桡倾等运动,运动前后摄腕关节正、侧位X线片,测量并观察头月角(α)、桡月角(β)、头月正位角(θ)、融合体高度(H)和融合体宽度(W)的变化,并行统计学分析。结果腕关节由运动前中立位至掌屈50°时,α、β、H值与运动前相比,差异均有统计学意义(P<0.01);背伸至40°时,α、β、H值与运动前相比,差异有统计学意义(P<0.01)。腕关节由中立位至桡倾15°时,θ与W与运动前比较,差异有统计学意义(P<0.05);至尺倾25°时,θ与W的运动前比较,差异有统计学意义(P<0.05)。结论头月角、桡月角、头月正位角、融合体高度和融合体宽度等指标可用于衡量四角融合术后融合体的稳定性。     

Four-corner arthrodesis: influence of the position of the lunate on postoperative wrist motion: a cadaveric study

PURPOSE: Evaluate the influence of the position of the lunate on postoperative wrist motion in four-corner arthrodesis. METHODS: Six upper cadaveric limbs were evaluated, comparing the total arc of motion in each wrist after simulating four-corner arthrodesis. The lunate was fixed in 3 different positions: neutral (0 degrees ), extended (30 degrees ), and flexed (20 degrees ). Statistical analyses (ANOVA and Bonferroni tests) were carried out to establish the significance of differences in articular motion in these 3 positions. RESULTS: Significant statistical differences were observed in full wrist extension. No significant differences, however, were found in flexion-extension total arc of motion, radial deviation, or ulnar deviation. CONCLUSIONS: According to our results in this cadaveric model, the position of the lunate affects postoperative wrist flexion and extension after four-corner arthrodesis. The flexed lunate position increases postoperative wrist extension and restrains wrist flexion. Inversely, the extended lunate position improves articular flexion and limits extension. Total arc of motion of the fused wrist does not vary in the 3 lunate positions.     

Scapholunate instability: current concepts in diagnosis and management

Injuries to the scapholunate joint are the most frequent cause of carpal instability and account for a considerable degree of wrist dysfunction, lost time from work, and interference with activities. The complex arrangement and kinematics of the 2 rows of carpal bones allows for an enormous degree of physiologic motion, and a hierarchy of primary and secondary ligaments serves to balance an inherently unstable structure. Although insufficient to cause abnormal carpal posture or collapse on static radiographs, an isolated injury to the scapholunate interosseous ligament may be the harbinger of a relentless progression to abnormal joint mechanics, cartilage wear, and degenerative change. Intervention for scapholunate instability is aimed at arresting the degenerative process by restoring ligament continuity and normalizing carpal kinematics. In this review, we discuss the anatomy, kinematics, and biomechanical properties of the scapholunate articulation and provide a foundation for understanding the spectrum of scapholunate ligament instability. We propose an algorithm for treatment based on the stage of injury, degree of secondary ligamentous damage, and arthritic change.     

Medial approach for subtalar distraction bone block arthrodesis

Subtalar distraction bone block arthrodesis is a useful technique commonly employed in the management of calcaneal and talar fracture malunion. Traditionally it is performed via a posterolateral or extensile lateral approach, however such approaches have been associated with wound complications, particularly secondary to the added stress caused by the subtalar distraction crucial to this technique. Medial approaches to the subtalar joint have been used in other procedures but have not been reported in subtalar distraction bone block arthrodesis. A novel case and technique illustrating the medial approach for subtalar distraction bone block arthrodesis is discussed.Level of clinical evidenceLevel 4.     

Success of Different Knee Arthrodesis Techniques After Failed Total Knee Arthroplasty: Is There a Preferred Technique?

Arthrodesis is a widely accepted treatment for failed total knee arthroplasty when further revision is contraindicated. In this study, we retrospectively review the pre-operative characteristics, operation techniques, treatment plans, and eventual outcomes in 42 consecutive patients (43 knees) who underwent knee arthrodesis at a single institution. Femorotibial fusion was achieved in 30 cases (75.0%). No cases of implant failure were recorded. Post-operative complications occurred in 20 cases (46.5%). Repeat arthrodesis was performed in 4 cases, and 2 patients eventually required above-the-knee amputation. Comparing the cases with successful vs. unsuccessful outcomes, there was a significant difference in days until hospital discharge following arthrodesis (P = .026), mean erythrocyte sedimentation rate prior to arthrodesis (P = .012), and the proportion of patients with post-operative wound complications (P = .021).     

Total hip arthroplasty for fused hips; planning and techniques

Conversion of an arthrodesed or fused hip to total hip arthroplasty (THA) is a challenging orthopedic problem due to the effects of previous operations, the altered anatomy, atrophy of the muscles, arthritis of neighboring joints, and limb length discrepancy. This prospective work included conversion of 19 arthrodesed hips to THA. The failure rate was 5% after an average follow-up period of 7 years. Specific preoperative planning and refined techniques have been elucidated to achieve a success rate nearly similar to that of primary THA.