Mild-to-moderate hip osteoarthritis and hip bracing influence hip and knee biomechanics during 90° turns while walking.

Abstract

Turning movements are frequently encountered during daily life and require more frontal and transverse hip mobility than straight walking. Thus, analysis of turning might be an insightful addition in the evaluation of conservative treatment approaches for hip osteoarthritis patients. The study objective was to quantify the effects of mild-to-moderate symptomatic hip osteoarthritis on lower-body turning biomechanics and evaluate the effects of hip bracing in this cohort. Biomechanical analysis of 90° step and spin turns in 21 persons with hip osteoarthritis and 21 healthy controls (case-control-study) and intervention study on the effects of hip bracing in hip osteoarthritis participants. Hip and knee kinematics and dynamics were compared using independent sample t-tests or one-way repeated measure ANOVAs. Persons with hip osteoarthritis have reduced peak hip extension and sagittal and transverse hip range of motion during turning. During the spin turn reduced hip adduction and frontal hip range of motion were found. Bracing increased the movement velocity at turn initiation and limited the transverse hip range of motion during both turns but increased knee peak adduction and internal rotation moments during spin turns. Persons with hip osteoarthritis present altered hip kinematics during 90° spin turns in all movement planes. Their inclusion during clinical movement analysis might facilitate the detection of mobility deficits at an early disease stage. Bracing led to higher movement velocity at turn initiation without increasing load at the hip joint and reduced transverse hip range of motion, avoiding the painful reaching of range of motion endpoints.