Medial tibial plateau fracture following unicompartmental knee arthroplasty – characteristics, risk factors, pathogenesis and treatment methods. Literature review and case report

Abstract

Introduction. Medial tibial plateau fracture (MTPF) after medial unicompartmental knee arthroplasty (UKA) is a rare but significant complication. Materials and methods. MEDLINE, ScienceDirect and Cochrane Library databases were searched using specific search terms. The inclusion criteria were articles in English, medial unicompartmental knee arthroplasty intraoperative or stress MTPF, reported patients’ demographics and fracture characteristics, the treatment process, any case with a follow-up for a minimum of 3 months and the reported outcome. The exclusion criteria were lateral tibial plateau fracture, traumatic injury, all cases with a follow-up shorter than 3 months and no reported outcome. Results. From 374 records initially found, 36 were included in the analysis highlighting the characteristics, causes and mechanisms of UKA-related MTPF. As to the treatment outcomes, only 10 studies with a total of 19 cases met our inclusion and exclusion criteria. What was also reported was a case report of a 52-year-old patient diagnosed with MTPF one week after UKA and treated using ORIF with support plate and bone augmentation. At the 8-month follow-up, the patient was complaint-free and received 88 points in the KOOS Score. Conclusions. Several measures were proposed in the literature to minimize the risk of UKA-related MTPF. One of them is appropriate patient selection (BMI, BMD). As to the operative technique, positioning tibial pins too close to the medial tibial cortex and tibial plateau, extending the sagittal and vertical cut, damaging the posterior cortex and using excessive force during hammering should be avoided. In addition, the proper tibial component size and placement (considering the gender, race and knee alignment) is also important. UKA-related MTPF was reported to be managed with either conservative treatment, ORIF or revision to total knee arthroplasty (TKA). While conservative treatment carries a high risk of failure, and the revision to TKA is a massive procedure associated with the removal of all UKA components, ORIF was reported to bring favorable outcomes, being less invasive than revision to TKA.