Hip joint range of motion:
a) Rotation (transverse plane motion)
Generally assumed to be needing >45 degrees of external and internal rotation (90 degrees total). Importance of range and direction of motion in the transverse plane is that a contracture or osseous problems may result in an abnormal position of the limb and affect the angle of gait.
• patient sitting with knee flexed to 90 degrees
• hip joint is internally and externally rotated – observe extreme position
• external rotation is achieved by keeping one hand on the knee to stabilise it and moving the foot medially with the other hand until resistance is felt at the hip
• internal rotation is achieved by keeping one hand on the knee to stabilise it and moving the foot laterally with the other hand until resistance is felt at the hip – observe the pelvis and make sure that it is not elevate at end range of the hip joint (this will falsely increase the range)
• repeat with patient prone (hip extended) - observe extreme position
• the ranges of motion can be drawn as a line on an up-side-down semi circle that represents the entire possible range of motion of the hip joint
The so-called ‘neutral position’ of the hip is the midway point in its total range of motion.
A tractograph aligned with the tibial shaft and vertical can be used to measure range of motion or the range can be observed as being adequate or inadequate and if internal rotation is the same as external rotation. Alternatively a gravity goniometer with callipers can be placed on the femoral epicondyles
If there is a restriction in internal or external rotation of the hippo and it is evident in only one position (ie hip flexed or hip extended) indicates a soft tissue contracture (femoral position). If there is a restriction in internal and external rotation of the hip and it is evident in only one position (ie hip flexed and hip extended) indicates an osseous anomaly (femoral torsion).
b) Flexion/extension (sagittal plane motion)
Generally assumed to be:
Flexion with knee flexed > 75-90 degrees
Flexion with knee extended > 120 degrees
Extension with knee flexed > 20 degrees
Extension with knee extended > 30 degrees
• patient supine
• patient prone
c) Abduction/adduction (frontal plane motion)
Generally assumed to need:
> 45 degrees abduction from midline
> 30-45 degrees adduction from midline