Αbsorbable Plates for Isolated Ulnar Diaphyseal Fractures in Adults – A Case Series Study

INTRODUCTION: Absorbable materials have been used as fixation devices in orthopaedic surgery. However, their use for treating isolated ulnar diaphyseal fractures in adults has not yet been studied. The aim of this study was to assess whether Inion OTPS™ absorbable implants consisting of L-lactide, D, L-lactide, and trimethylene carbonate provide adequate fixation for the healing of isolated ulnar diaphyseal fractures, their complication rate, and the patients’ clinical functional outcome. MATERIALS AND METHODS: Three consecutive patients (all women; mean age, 45 years, and range 38–55 years) with isolated, unstable ulnar fractures were enrolled and treated operatively using Inion OTPS™ absorbable plates and screws. Discontinuation of the study was decided because of the early failure of all implants. The patients were assessed clinically (DASH Score and grip strength) and radiographically at 6 weeks, 3 months, 6 months, and 9 months. The incidence of late foreign body reactions was evaluated for 10 years follow-up period. RESULTS: Implant failure was noticed radiographically in the early post-operative period in all three patients. Subsequently, one patient was treated operatively using metallic devices, and the other two with prolonged splinting. All fractures healed uneventfully in variable time frames. No foreign body reactions were noticed during and beyond the degradation period, other than a small painless mass in one case. CONCLUSION: The results of the current study suggest that the Inion OTPS™ plating system is not appropriate for the fixation of isolated unstable ulnar diaphyseal fractures. It seems that these specific implants cannot withstand the internal mechanical forces of this anatomical area despite the protective splinting.