Clinical Outcomes of Pyrocarbon Hemiarthroplasty: A Short-Term, Multicenter Study.

Abstract

Unacceptable pain relief after hemiarthroplasty (HA) has limited its utilization for shoulder replacement. The material properties of pyrolytic carbon-graphite composites may result in less abrasion compared with metal bearing surfaces, theoretically decreasing glenoid-sided pain and erosion. This prospective, single-arm, multicenter study was performed to evaluate the short-term clinical outcomes and implant survivorship of pyrocarbon HA. The enrollment of 157 patients occurred at 18 sites between December 2015 and April 2017 as part of an Investigational Device Exemption protocol. The Constant score, American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, patient satisfaction, EuroQol-5 Dimensions (EQ-5D) score, and active range of motion were evaluated. A historical control cohort treated with cobalt-chromium HA was identified through a propensity score subclassification analysis. The pyrocarbon HA and cobalt-chromium HA cohorts were compared on the basis of a Composite Clinical Success (CCS) rate, defined as a ≥17-point change in the Constant score without revision or a device-related adverse event. Of the 157 patients enrolled, 144 had short-term follow-up (mean, 24.4 ± 1.2 months), 10 were lost to follow-up, and 3 underwent revision prior to 24 months due to pain or low-grade infection. The mean patient age was 52.4 ± 10.9 years (range, 19 to 73 years). There were significant improvements in all active range-of-motion and patient-reported outcomes. The outcomes of the pyrocarbon HA cohort (n = 157) were compared with those of the cobalt-chromium HA group (n = 169) eligible for a minimum 24-month follow-up, in which multiple imputation was employed to address missing data. The CCS was 82.7% for the pyrocarbon HA group and 66.8% for the cobalt-chromium HA group (p < 0.001). Pyrocarbon HA demonstrated favorable results at a short-term follow-up and improved outcomes compared with the propensity score subclassification-derived cobalt-chromium HA cohort. Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.