Functional outcome and complications following PHILOS plate fixation in proximal humeral fractures

Proximal humeral fractures account for approximately 5% of all fractures. New plating techniques have been developed to improve stability. The purpose of this study was to evaluate functional outcome following plate fixation with the Proximal Humeral Internal Locking System (PHILOS) and to analyze potential implant-related complications.

The PHILOS plate was used for internal fixation of displaced proximal humeral fractures in 28 patients (20 females, 8 males; mean age 60.7+/-12.9 years). Fractures were caused by low-energy trauma (fall from standing height) in 21 patients, and by an accident while skiing or cycling in seven patients. Involvement was on the right in 16 cases and on the left in 12 cases. According to the Neer classification, 8, 12, and 8 patients had displaced 2-, 3-, or 4-part fractures, respectively. All patients received a similar physical therapy program following internal fixation with the PHILOS plate. The patients were assessed clinically and radiographically after a mean follow-up of 25.2+/-11.8 months. Functional outcome was assessed using the Constant-Murley score adjusted for age and gender. Range of motion and shoulder abduction strength were measured. The patients were also evaluated with the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and a visual analog scale (VAS). Complications during the follow-up period were recorded.

Twenty fractures (71.4%) healed in good anatomical position. At the end of the follow-up period, the mean Constant-Murley score was 57.9+/-21.7, and the mean age- and gender-adjusted Constant-Murley score was 67.5+/-23.6. The results were excellent or good in 16 patients (57.1%), moderate in one patient (3.6%), and poor in 11 patients (39.3%). The mean DASH and VAS scores were 28.3+/-24.3 and 75.4+/-21.2, respectively. Eleven complications (39.3%) were seen during the follow-up period. Reoperation was required in eight patients (72.3%). Complications included avascular necrosis of the humeral head in two patients (7.2%), subacromial impingement in six patients (21.4%), loosening of a locking head screw in one patient (3.6%), and transiently decreased radial nerve sensation in two patients (7.2%). Subacromial impingement was mainly caused by the superior plate position.

Our results demonstrate that the PHILOS plate provides sufficient fracture stabilization in the treatment of proximal humeral fractures of elderly patients.