Proximal tibial bone loss in the first 2 years after unicondylar knee arthroplasty: Anatomical pattern, predictors and clinical correlation

Tibial stress fracture, anteromedial bone pain, and early subsidence could occur after unicondylar knee arthroplasty (UKA). The change in metaphyseal tibial bone density (MTBD) in the coronal and sagittal planes after UKA might be a contributing factor, but this has rarely been investigated. The aim of this study was to assess the regional and temporal change in MTBD in the coronal and sagittal planes in the first 2 years after UKA. Patients with fixed-bearing medial UKA were recruited. The change in MTBD in the first 24 months after UKA using digital radiological densitometry (DRD) was measured. Potential predictors and clinical correlations were analyzed. Eighty-four cases (female 60%) were selected for review. The follow up time was 63 (±17) months. Anterior and medial regions had the largest proportion of cases with MTBD reduction (90–97%, P