Biomechanical Comparison of Reconstruction Techniques for Disruption of the Acromioclavicular and Coracoclavicular Ligaments

Albert W. Pearsall IV, MD, J. Marcus Hollis, PhD, George V. Russell, Jr., MD, David A. Stokes, MD

Disclosures

J South Orthop Assoc. 2002;11(1) 

In This Article

Abstract and Introduction

Injuries to the acromioclavicular joint are common. For selected injuries, operative reconstruction is recommended. The purpose of the current study was to compare three reconstruction procedures: (1) nine strands of woven polydioxanonsulphate (PDS II) suture passed through the clavicle and around the coracoid; (2) procedure No. 1 with 50% of the coracoacromioclavicular ligament placed through 2 clavicular drill holes; (3) No. 5 Merselene tape passed through 2 drill holes in the clavicle and acromion, with 50% of the coracoacromial ligament transferred to the clavicle. Fourteen fresh frozen human shoulders were tested using a 6 degree-of-freedom testing device. The intact shoulder showed significantly less displacement than any of the reconstructions. Merselene tape plus ligament showed the largest displacement, and PDS II braid plus ligament showed the least displacement. None of the procedures reconstituted acromioclavicular joint stiffness to intact state levels, though improved acromioclavicular joint stiffness was noted with a PDS braid plus ligament.

Disruption of the acromioclavicular joint has long been recognized as a disabling injury to patients who are involved in overhead activities.[1] Injuries to this joint may result in instability and discomfort.[2,3] The mechanism of injury to the acromioclavicular joint has been well described, frequently resulting from a fall on the shoulder with the scapula and extremity being driven downward and forward on the clavicle.[4,5] Rockwood et al[2] and Allman[6] classified these injuries into the 6 injury patterns frequently described today. While conservative treatment is recommended for most injuries classified as grade I, II, or III, reconstruction of the acromioclavicular joint has been advocated in selected grade III and most grade IV to VI injuries.[2]

Many types of acromioclavicular (AC) joint reconstruction procedures have been described in the literature, including primary joint fixation, coracoclavicular joint reconstruction, excision of the distal clavicle, and dynamic muscle transfers.[7,8] Weaver and Dunn[8] originally described transfer of the coracoacromial ligament as a means of coracoclavicular ligament reconstruction. A modificaton of their original procedure, involving augmentation of the coracoclavicular ligaments, was developed to protect the AC ligament during healing and to enable earlier rehabilitation.[9,10] Combinations of these techniques are now used to anatomically restore the disrupted acromioclavicular joint. Despite the extensive clinical literature describing these surgical techniques, we found only 3 recent biomechanical studies analyzing the strength of these surgical constructs.[11,12,13]

The purpose of the current study was to compare the stiffness, strength, and mode of failure of 3 acromioclavicular joint reconstruction procedures: (1) nine strands of woven No. 1 polydioxanone sulfate (PDS II) suture passed through claviclar drill holes and around the coracoid; (2) procedure No.1 with 50% of the coracoacromial (CAC) ligament secured to the clavicle through 2 drill holes; and (3) No. 5 Merselene tape passed through 2 drill holes in both the clavicle and acromion, in conjunction with securing 50% of the CAC ligament to the clavicle through 2 drill holes.

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