Can the glenopolar angle be used to predict outcome and treatment of the floating shoulder?

OBJECTIVE: Displaced ipsilateral fractures of the clavicle and the glenoid neck are usually the result of high-energy trauma. The objective of this study is to evaluate the association of the glenopolar angle (GPA) with the clinical outcome of the floating shoulders.

METHODS: Seven patients treated conservatively and nine patients with clavicular fracture treated operatively were evaluated retrospectively. The GPA of the affected (a-GPA) and unaffected (u-GPA) shoulders, and the change (d-GPA) were measured. The Constant-Murley score of the affected (a-CS) and unaffected (u-CS) shoulders, and the change (d-CS) were measured at the last follow-up.

RESULTS: The mean follow-up was 25 months, and the score was 69.7 points. Patient age had no effect on the clinical outcome, and the change in GPA in the affected shoulder between the initial and last follow-up for the nonoperated and operated groups did not differ statistically (p > 0.05). There were positive correlations between a-CS and a-GPA (r = 0.760, p < 0.05) and between d-GPA and d-CS (r = 0.643, p < 0.05) and negative correlations between a-GPA and d-CS (r = -0.962, p < 0.05) and between d-GPA and a-CS (r = -0.703, p < 0.05).

CONCLUSION: The simple measurement of GPA may yield useful prognostic information and help in making decisions concerning the floating shoulder.