Treatment of patellar fractures using bioresorbable forged composites of raw particulate unsintered hydroxyapatite/poly-L-lactide cannulated screws and nonabsorbable sutures.

Abstract

Forged composites of raw particulate unsintered hydroxyapatite/poly-L-lactide (F-u-HA/PLLA) implants are widely used in surgeries because they possess high mechanical strength, bioactivity, and radio-opacity. We previously reported that F-u-HA/PLLA implants were useful for treating lateral tibial condylar, lateral humeral condylar, and ankle fractures. The study aim was to investigate the efficacy of F-u-HA/PLLA cannulated screws and FiberLoop® for treating transverse patellar fractures. From April 2013 to February 2019, 15 patients with transverse patellar fractures were treated with F-u-HA/PLLA cannulated screws and FiberLoop® as follows: Open reduction and internal fixation (ORIF) were performed with two F-u-HA/PLLA cannulated screws and a temporary fixation Kirshner wire (K-wire). Three No. 2 FiberLoops® were inserted into these two screw holes and the K-wire hole for temporary fixation. All patients were allowed to full weight-bearing gaits using a knee brace. Knee range of motion exercise was initiated on postoperative day 1. Knee flexion was restricted to ≤90° for 1 month postoperatively. Radiograph was performed to evaluate fracture healing, screw breakage, reduction loss, and screw radio-opacity. Clinical outcomes and postoperative complications were assessed. The average follow-up was 16.0 months. All fractures were successfully united. Screw breakage, reduction loss, osteolysis, and radiolucent zones around the screws were not observed at the final radiographic follow-up. All F-u-HA/PLLA screw shadows were observed during the follow-up. The average range of flexion and extension were 132.0° and -2.7°, respectively. No patients experienced deep infection episodes, late aseptic tissue reactions, or foreign body reactions postoperatively. No patients complained of pain at the final follow-up. All patients returned to their pre-injury work level and activities of daily living. Our results strongly suggest that ORIF with F-u-HA/PLLA screws and FiberLoop® could be an alternative treatment option for transverse patellar fractures.