Abstract
Complex proximal humerus fractures have been described as the unsolved fracture. Review of literature shows a variety of treatment methods and results. We present the results of a prospective study of 47 complex proximal humerus fractures treated by PHILOS (Proximal Humeral Internal Locking System) plate. The aim of this study was to assess the effectiveness of the PHILOS plate in the surgical treatment of Neer’s type 3 & 4 fractures.
We operated upon 47 patients (mean age 56yrs) between March 2002 and January 2006 for fixation of 3 part (28 patients) and 4 part (19 patients) fractures at a level 1 trauma centre. An independent observer reviewed patients at 6 monthly intervals for clinical and radiological assessment. Outcome measures included DASH and Constant scores.
42 patients were available for follow up, which ranged from 12–66 (average 24.4) months. Recovery of movements, and relief in pain was satisfactory in most of the patients, but the strength of shoulder did not recover fully in any patient. There were two failures in our series, one due to breakage of plate and another due to non-union; both treated successfully by revision. 4 patients (8%) had radiological signs of avascular necrosis of humeral head but only 2 of them were symptomatic requiring further treatment. Pain due to impingement was noted in several patients leading to removal of plate (6 patients) and subacromial decompression (3 patients). We encountered the problem of cold welding and distortion of screw heads, while removing the plate. The broken plate was subjected to biomechanical and metallurgical analysis, which revealed that the plate is inherently weak at the site of failure.
We concluded that in spite of the above-mentioned complications, the PHILOS plate is a reliable implant to fix 3 and 4 part proximal humeral fractures. We were particularly impressed with the satisfactory results of fixation in 4 part fractures. However, we are not convinced about its strength. The plate may cause impingement in some patients necessitating its removal later on, which itself may not be easy.
Level of Evidence: Therapeutic study, level IV (case series).
Correspondence should be addressed to Mr Bimal Singh, c/o BOSA at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE
