Intraarticular osteotomy of malunited tibial plateau fractures: an analysis of clinical results with a mean follow-up after 4 years

Purpose Malunions are a common complication after tibial plateau fractures (TPF), leading to stiffness, pseudo-instability and posttraumatic osteoarthritis. The purpose of this study was to analyse the clinical outcome after intraarticular osteotomy of malunited TPF and to perform a failure analysis. Methods Between 2013 and 2018, 23 patients (11 males, 12 females; 43.8 +/- 12.8 years) with intraarticular osteotomy after malunited TPF were included in the retrospective study. Clinical examination and postoperative scores were collected with a minimum follow-up of 24 months. Malunion was measured on pre- and postoperative CT scans and localized according to the 10-segment classification while the leg axis in the frontal plane was measured pre- and postoperatively on long leg standing radiographs. Results Excellent and good clinical outcome was achieved in 73.9% (n = 17) of the cases and patient related outcome improved significantly (Tegner 3.3 +/- 1.6-5 +/- 1.8,p < 0.001; clinical Rasmussen 14.6 +/- 3.8-24.9 +/- 4.4,p < 0.001). Radiological parameters also improved as an intraarticular step-off was reduced from 9 +/- 3.8 to 0.6 +/- 0.8 mm (p < 0.001) and a lower limb malalignment from 7.2 +/- 4.8 degrees to 1.5 +/- 1.9 degrees (p = 0.003). Failure analysis showed that an impaired clinical result correlated with a postoperative extension (n = 3,p < 0.001) and flexion deficit (n = 4,p = 0.035). Conclusion Intraarticular osteotomy of malunited TPF lead to good clinical results with significant clinical and radiological improvement in most cases while an impaired patient outcome correlated with a limited range of motion. This study is the first failure analysis of intraarticular osteotomy after malunited TPF published up to now.