Hook-Plate Fixation in Patients with Acute Acromioclavicular Joint Dislocation Improved Radiographic But Not Clinical Outcomes Compared with Nonoperative Treatment

Cox, Charles L. MD, MPH

Journal of Bone & Joint Surgery - American Volume:
doi: 10.2106/JBJS.16.00582
Evidence-Based Orthopaedics
Author Information

1Vanderbilt University Medical Center, Nashville, Tennessee

Article Outline

Canadian Orthopaedic Trauma Society. Multicenter randomized clinical trial of nonoperative versus operative treatment of acute acromio-clavicular joint dislocation. J Orthop Trauma. 2015 Nov;29(11):479-87.

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In patients with high-grade, acute acromioclavicular (AC) joint dislocation, does operative repair with hook-plate fixation improve patient outcomes more than nonoperative treatment?

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Randomized (allocation concealed), unblinded, controlled trial with 2 years of follow-up and intention-to-treat analysis.

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11 hospitals in Canada.

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83 patients 16 to 60 years of age (mean age, 38 years; 94% men) who had a closed, complete (Rockwood grade-III to V) AC joint dislocation and were recruited ≤28 days after the injury. Exclusion criteria included previous surgery on the injured shoulder, scapulothoracic dissociation, vascular or ipsilateral shoulder injury, coracoid process fracture of the injured shoulder, or limited life expectancy. >80% of patients were assessed for secondary outcomes at 1 year; <80% were assessed for the primary outcome or for any outcome at >1 year.

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Operative repair (n = 40) or nonoperative treatment (n = 43). Operative repair was done ≤28 days after the injury and included anatomic reduction of the AC joint and fixation with a hook plate and screws. Ligament reconstructions, transfers, and subcoracoid fixation were not done. After surgery, patients used sling support, and physiotherapy was started at 2 weeks. Hook plates could be removed 6 months after implantation or earlier if clinically indicated. Nonoperative treatment included sling support for 4 weeks, followed by standard physiotherapy, including active and passive exercise and then resistance and strength exercises starting 6 weeks after the injury. In both groups, pendulum exercises could be added at the surgeon’s discretion.

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Main outcome measures:

Secondary outcomes included the Constant-Murley shoulder score (higher score = better outcome), radiographic assessment, return to work, and cosmesis. Complications were also reported. The primary outcome (Disabilities of the Arm, Shoulder and Hand [DASH] score at 1 year) is not reported here because <80% of patients completed assessments.

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Main results:

Constant-Murley scores were lower (worse outcome) in the operative treatment group than in the nonoperative treatment group at 6 weeks (mean, 51 vs. 75; p < 0.001), 3 months (mean, 69 vs. 86; p < 0.001), and 6 months (mean, 80 vs. 92; p < 0.001); the groups did not differ at 1 year (mean, 91 vs. 91; p = 0.83). The operative repair group had better radiographic outcomes (smaller coracoclavicular distance [p < 0.05] and more patients with a reduced AC joint [p < 0.001]) at all time points in comparison with the nonoperative treatment group. More patients returned to work at 3 months after nonoperative treatment than after operative treatment (76% vs. 43%; p = 0.004); the groups did not differ in terms of the proportion of patients who returned to work (about 90% in each group) or who were unhappy with the shoulder appearance (16% vs. 5.3%; p = 0.23) at 1 year. 7 major complications occurred in the operative treatment group, and 2 occurred in the nonoperative treatment group.

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In patients with acute AC joint dislocation, operative repair with hook-plate fixation improved radiographic but not clinical outcomes compared with nonoperative treatment.

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Source of funding:

Osteosynthesis and Trauma Care Foundation; Orthopaedic Trauma Association; Synthes.

For correspondence: Dr. M.D. McKee, Department of Surgery, Toronto, Ontario, Canada. E-mail address: mckeem@smh.ca

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In this trial, which was partially funded by Synthes, the authors chose to treat acute high-grade AC joint injuries with a Synthes hook plate. This surgical technique requires a second procedure to remove the plate (with higher potential cost and risk to patients), requires proper attention to plate placement to avoid major complications (with an 18% rate of major complications in this study), and fails to directly repair or reconstruct the anatomic injury (coracoclavicular and AC ligament disruption). The trial represents high-level evidence because of its randomized, prospective design and multicenter enrollment strategy. The generalizability of the findings is limited because (1) only 45% of eligible patients were enrolled, (2) only 67% of randomized patients completed assessments for the primary outcome (DASH score at 1 year), (3) the rate of patient follow-up at 2 years was poor (51% for radiographic assessment and 58% for Constant-Murley scores and cosmesis), and (4) grade-III, IV, and V AC joint injuries were grouped together.

The results showed that nonoperative treatment was associated with improved short-term patient-reported outcomes and fewer complications but that operative treatment was associated with improved radiographic outcomes. With the current emphasis on scapular positioning as it relates to glenohumeral function, readers are left to wonder about the future effects of a chronically dislocated AC joint and possible protracted scapular posture in the nonoperative treatment group. However, this trial provides useful clinical guidance for the initial treatment of acute high-grade AC joint injuries. Initial nonoperative treatment seems to be a viable and potentially cost-effective option even for grade-IV and V AC joint injuries; surgery can be reserved for patients who remain symptomatic over time. Future studies are needed to determine baseline risk factors for subsequent failure of nonoperative treatment and the long-term prognosis for patients with high-grade AC joint injuries.

Disclosure: The author indicated that no external funding was received for any aspect of this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article.

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