Association between patellar height and spinopelvic alignment in a static posture: A cross-sectional observational...

BackgroundAltered patellar height is associated with abnormal patellofemoral joint mechanics and is considered a structural risk factor for pain and instability. Although patellar height has been primarily explained by local knee structures, the contribution of static spinopelvic alignment remains unclear.ObjectiveTo compare spinopelvic alignment according to patellar height and to explore whether pelvic and spinal alignment variables are independently associated with patellar height.MethodsThis cross-sectional observational study included 71 young adults classified into patella alta, normal, and patella baja groups using the Insall-Salvati index. Pelvic tilt angle, lumbar lordosis angle, and thoracic kyphosis angle were measured in a standing position. Group differences were analyzed using one-way analysis of variance with Bonferroni post hoc tests. Multiple linear regression analysis was performed to identify independent predictors of patellar height.ResultsSignificant group differences were observed in pelvic tilt, lumbar lordosis, and thoracic kyphosis (all p < 0.001). The patella alta group demonstrated the greatest anterior pelvic tilt and lumbar lordosis, whereas the patella baja group showed reduced spinal curvature. In regression analysis, pelvic tilt angle independently predicted patellar height (β = 0.601, p < 0.001) explaining 44.6% of the variance, while lumbar lordosis and thoracic kyphosis were not significant predictors.ConclusionPatellar height is significantly associated with pelvic alignment, particularly anterior pelvic tilt. These findings highlight the importance of considering proximal spinopelvic alignment as a related postural factor when assessing patellar height.