Cam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement. We recruited nine participants with cam and/or pincer morphologies and with pain, 13 participants with cam and/or pincer morphologies and without pain, and 11 controls from a population-based cohort. We scanned hips in active squatting and passive sitting flexion, adduction, and internal rotation using open MRI and quantified anterior femoroacetabular clearance using the β angle.Aims
Methods
The “Knot of Henry” was dissected in 16 embalmed cadaveric feet to reveal the complex interconnections between flexor hallucis longus (FHL) and flexor digi-torum longus (FDL) tendons. Three distinct anatomical patterns were observed. Tension was applied manually to FHL or FDL proximal to the Knot. Digit movement was different depending on the anatomical pattern. FHL or FDL tendon transfer is an accepted technique to prevent progression of acquired plano-valgus deformity. In order to minimise donor deficit, we suggest the use of either FHL or FDL should be based on assessment of the anatomical pattern at the time of surgery.
