Comparison of biomechanical and proprioceptive function following resurfacing arthroplasty and standard total hip replacement

• Main Author: Wells, Julie
• Published: University of Strathclyde 2009
• Subjects: 612
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.510724

Resurfacing arthroplasty is gaining popularity as an alternative method of hip joint reconstruction for younger individuals. Hip resurfacing has several perceived benefits over the conventional total hip arthroplasty (THA), including a greater range of motion offered by the larger diameter bearings and improved abductor muscle function due to femoral neck preservation. Literature reports that hip resurfacing often provides a 'natural' feel and allows greater functional return, which may be related to improved proprioception. However, existing studies have failed to fully substantiate the functional merits of resurfacing arthroplasty over those provided by the traditional stemmed THA. Outcomes were evaluated for 31 patients with primary unilateral resurfacing or standard stemmed THA at 3 and 12 months following surgery. Kinematic and kinetic data were collected while subjects completed level walking. stair ascent and stair descent activities. 3-dimensional hip moments and angles were compared between the arthroplasty groups. Threshold motion detection sense of the hip was tested to quantify hip joint proprioception, by administering passive abduction and flexion motion stimuli using a validated test rig and comparing threshold detection angles. Hip moments showed no statistically significant difference due to arthroplasty type. Slightly greater peak hip angles were achieved by those with standard THA. The resurfacing group showed greater walking velocities. Threshold detection angles were statistically similar. Resurfacing and standard THA demonstrated equivalent proprioceptive and functional outcomes. Motion detection sense did not differ due to arthroplasty type. Preserving the femoral offset did not appear to benefit abductor function and the greater diameter resurfacing bearings did not result in greater functional range of motion. The increased offset and greater head-neck ratio provided by the prosthetic neck may benefit abductor function and increase motion to an extent which meets the benefits of hip resurfacing. Given that there are greater risks and difficulties associated with hip resurfacing, standard THA may be viewed as the more desirable alternative for young active patients.