Is PHILOS as good as it sounds to be? Analysis of complications and functional outcome of PHILOS plating

Abstract

Aim: Proximal humeral fractures have posed a challenge for internal fixation. Among several methods, most recently, PHILOS (Proximal humeral Internal Locking system) plates have been promoted as most effective method to achieve fixation and union. However, there are no enough studies evaluating the complications and outcome of PHILOS plating. Some studies have shown complication rates ranging from 3.7% to 33.5%. So with this study, we aim to analyze the efficacy and the functional outcome following open reduction and internal fixation with PHILOS plate for displaced proximal humerus fractures. Methodology: In this study, we identified 38 patients in our orthopaedic unit treated surgically by open reduction and internal fixation using the proximal humeral internal locking system (PHILOS) plate from January 2013 to December 2016. All those patients who had a radiographic and regular clinical follow-up for at least 6 months were included in the analysis. Surgery was done for displaced 2-part, 3-part and 4-part proximal humerus fractures (Neer’s Classification) through deltopectoral approach during the time period. Six patients who did not fit into inclusion criteria, did not attend regular follow-up or had incomplete records were excluded from analysis. The study group comprising 32 patients was analyzed for complications and functional outcome by studying patient records and x-rays. The functional outcome was measured using Constant shoulder scoring system. Results: 68% of the patients were males (22 males and 10 females) and male to female ratio was 2.2:1. The mean age of the patients was 47 ± 16 years (Range 31-63 years). Involvement of left side proximal humerus fracture was more common (58%). 55% patients had 2-part fracture according to Neer’s classification. The range of movements at first, second and third follow ups increased gradually during subsequent follow ups. According to Constant Shoulder scores, 50% of the patients had excellent outcome followed by 21.9% good, 12.5% fair and 15.6% poor outcome. Total of 7 patients out of 32 had complications (21.8%) and most common complications noted were inadequate reduction, subacroimial impingement, adhesive capsulitis and loss of varus reduction. There were no nerve injuries or infection. Conclusion: Proximal humeral internal locking system (PHILOS) plate for the treatment of proximal humerus fractures leads to a satisfactory functional outcome in majority of the patients. However, functional results depend on correct anatomical reduction of the fracture and stable fixation. Complications still occur due to fracture severity and lack of technical expertise. However, complications like inadequate reduction, varus malalignment, subacromial impingement can still occur with this system. Varus malalignment was found to be a strong predictor of poor functional outcome