HEMIARTHROPLASTY FOR DISPLACED PROXIMAL HUMERUS FRACTURES, RESULTS OF TWO TYPES OF IMPLANTS

Abstract

Introduction: The goal of this study is to report the clinical and radiographic results of 2 types of implants used to treat 3 and 4 parts fractures of the proximal humerus.

Patients: Sixty-three patients (64 shoulders) were reviewed in this retrospective series. Forty women and 23 men were included, the mean age was 64 ± 12 (39–86). A group of 31 patients was managed with a ‘standard’ implant, a second group of 32 patients (33 shoulders) was managed with a ‘fracture’ implant. The delay between initial trauma and the surgical procedure was less than 4 weeks (1–30 days) for all patients.

Methods: All the procedures were carried out by a senior surgeon. The patients were reviewed by an independent observer with a mean follow-up of 59 ± 38 months (12–138) for a clinical and radiographic evaluation.

Results: In the ‘standard implant’ group; 84% of the patients were satisfied or very satisfied regarding the outcome of surgery. The subjective evaluation (SSV score) was 69% (30–100%). The active anterior elevation (AAE) was 117° ± 43° (30–180°), the active external rotation (AER) was 24° ± 20° (0–60°), the active internal rotation (AIR) was up to the T12 vertebra (buttocks-T8). The mean Constant score was 60 ± 20 points (24–95). The radiographic analysis revealed a greater tuberosity that was considered migrated, not healed or lysed in 65% of cases. The acromion – implant height was ≤ 7mm in 52% of the patients. In the ‘fracture implant’ group; all the patients were satisfied or very satisfied regarding the outcome of the surgery. The SSV score was 70% (20–100%). The AAE was 132° ± 36° (45–180°), the AER was 34° ± 16° (0–60°), the AIR was up to the L3 vertebra (buttocks-T8). The mean Constant score was 66 ± 16 points (33–95). The radiographic analysis revealed a greater tuberosity that was considered migrated, not healed or lysed in 33% of cases. The acromion – implant height was ≤ 7mm in 30% of the patients. The patients with a healed greater tuberosity in an adequate position had better Constant scores: 71 points versus 54 points for those with a greater tuberosity not healed/lysed or in a bad position (p=0.03). A healed greater tuberosity in an adequate position was obtained more constantly for the patients in the ‘fracture implant’ group (p=0.02).

Conclusion: A healed greater tuberosity in an adequate position is a significant parameter influencing the outcome of hemiarthroplasty for proximal humerus fractures. A fracture designed implant allows better greater tuberosity positioning and healing.