Evaluation of the use of the hook plate in Neer type 2 lateral clavicle fractures and Rockwood types 3-5 acromioclavicular joint dislocations.

PURPOSE: For most types of acromioclavicular (AC) injuries, treatment is well established. For Neer type 2 lateral clavicle fractures and Rockwood types 3-5 AC dislocations, the ideal treatment is still a point of debate. The purpose of this study was to evaluate the functional and radiological outcome in patients treated for one of these two lesions in our hospital.

METHODS

Our study group consisted of 30 patients with a Neer type 2 lateral clavicle fracture (n = 19) or Rockwood types 3-5 AC dislocation (n = 11) treated with the clavicle hook plate. All implants were removed after healing. At a mean follow-up of 40 months (12-92), data were collected by the analysis of questionnaires (DASH, NSST, OSS, SF-36), clinical examination (Constant-Murley score), and radiological evaluation (Zanca view).

RESULTS

The mean Constant score was 88 [standard deviation (SD) 8] compared to 92 (SD 6) on the contralateral non-operated side. The questionnaires resulted in the following scores: median DASH: 4.5 (0-70); median NSST: 100 (8-100); mean OSS: 41 (SD 8); mean SF-36: 81 (SD 12). The mean coracoclavicular (CC) and AC distances were not significantly different.

CONCLUSIONS

This study suggests that hook plate fixation is a reliable treatment for Neer type 2 lateral clavicle fractures and Rockwood types 3-5 AC injuries. It results in a good and comparable function of the shoulder when compared to the contralateral side, high union rate, good to excellent objective and subjective results, and allows early active motion with limited abduction. A disadvantage is the necessity to remove the plate.