Session II - Upper Extremity

The Floating Shoulder: Clinical and Functional Results

Kenneth A. Egol, MD; Patrick M. Connor, MD; Madhav A. Karunakar, MD; Michael J. Bosse, MD; Stephen H. Sims, MD; James F. Kellam, MD, Carolinas Medical Center, Charlotte, NC; Miller Orthopaedic Clinic and University of Michigan

Background: Displaced ipsilateral fracture of the clavicle and glenoid neck or acromioclavicular dissociation and ipsilateral glenoid neck fracture (floating shoulder) is a complex injury pattern that is usually the result of high-energy trauma. The appropriate treatment of these injuries is controversial, as good results have been reported in series of patients using either operative or non-operative treatment.

Purpose: To examine and compare the results of differing treatment of patients who had sustained the injury complex known as "floating shoulder".

Methods: Nineteen patients who sustained a displaced ipsilateral glenoid neck and clavicle fracture or acromio-clavicular separation ("floating shoulder") were retrospectively evaluated for this study. Treatment included nonoperative management (12) or operative treatment (7) depending on the degree of displacement, associated injury or surgeon preference. All patients were examined at final follow-up by a physical therapist and either a fellowship trained shoulder surgeon or orthopaedic traumatologist. At the time of follow-up examination, standard radiographs were obtained. In addition, each patient responded to 3 different validated objective functional outcome measures: the SF-36, the American Shoulder and Elbow Surgeons' (ASES) rating scale and the Disabilities of the Arm, Shoulder and Hand (DASH). Isokinetic strength testing of the affected shoulder was performed and the results compared to those of the uninvolved shoulder with respect to forward elevation and external rotation. The main outcome measures included fracture healing, functional outcome, patient satisfaction and muscular strength. Standard statistical methods were employed; the Mann-Whitney U test and Fischer's exact test were used to compare outcomes.

Results: Only forward flexion was found to be statistically greater in the operatively treated group (P =.03) than in the nonoperatively treated patients. Operatively treated shoulders were found to be weaker in external rotation at 300 kgm/sec and weaker in internal rotation at 180 kgm/sec. When normalized to hand dominance, no statistical conclusion could be made. Although operatively treated patients trended towards better functional results, there was no statistical difference between functional outcome of either group with regard to any of the 3 objective outcome measures. Complications during treatment were equally divided between operative and nonoperative patients.

Conclusion: Double disruptions of the superior suspensory shoulder complex are severe injuries associated with high-energy trauma. Based on our results, we cannot recommend operative treatment of a double disruption of the superior suspensory shoulder complex as an absolute. Each case must be assessed individually.