The importance of axial rotation of the lower limb : a systematic review of measurement methods

Assessment of lower limb alignment is a cornerstone of orthopaedics. Few studies look at rotational alignment in the axial plane as measured by femoral version (FV) and tibial torsion (TT), both of which have implications for hip, knee, and ankle pathology. This review provides an overview of the axial rotation and evaluates CT-based measurement methods for FV and TT to identify the most reliable and reproducible techniques for use in clinical practice. A systematic PRISMA-guided review assessed original CT-based methods, examining inter- and intraobserver reliability (intraclass correlation coefficient (ICC)), frequency of use, and validation. Seven FV and nine TT CT-based techniques were identified. FV had a weighted mean of 17.8° anteversion (-9° to 60°). TT had a weighted mean of 30.8° (2° to 82°). ICCs ranged from good to excellent. The Murphy method (FV) and Goutallier method (TT) had the highest reliability and clinical utility. Lower limb axial rotational profile plays an important role in the management of hip, knee, and ankle arthroplasty surgery as well as many other orthopaedic pathologies. The Murphy and Goutallier methods should be adopted as standard for measuring FV and TT. Their high reproducibility and validation make them ideal for consistent clinical and research use.