A prospective comparative study of functional outcome of 28 mm versus 36 mm femoral head sizes in uncemented total hip arthroplasty

Abstract

<div class="WordSection1"><p><strong>Background: </strong>Incidence of dislocation is about 1% to 6% for primary total hip arthroplasty (THA) and 4.8% to 13% for revision THA. The diameter of the femoral head is one of the important variables under the control of a surgeon. Larger heads with modern necks improve the head-to-neck ratio, increase jump distance, reduce component impingement, instability and increase ROM. Objective were to compare the functional outcome of 28 mm versus 36 mm head sizes in uncemented THA in terms of ROM and functional status.</p><p><strong>Methods: </strong>In this prospective comparative study conducted on 30 patients with 36 diseased hips undergoing primary THA with 28 mm and 36 mm femoral head sizes for degenerative arthritis aged between 20-70 years, in Sanjay Gandhi institute of trauma and orthopaedics, Bangalore from November 2019 to April 2021. All patients were followed up at 6, 12 and 24 weeks postoperatively and assessed for ROM and functional status using modified Harris hip score (HHS).</p><p><strong>Results: </strong>The flexion was 9.31 degrees, extension was 4.0 degrees, adduction was 3.35 degrees, abduction was 4.31 degrees, internal rotation was 6.13 degrees, external rotation was 9.06 degrees and modified HHS was more in patients who received 36 mm femoral head as compared to the patients who received 28 mm femoral head at the end of follow up.</p><p><strong>Conclusions: </strong>We conclude that the use of 36 mm femoral head provides better improvement in the range of motion, functional outcome, and better patient and surgeon satisfaction than 28 mm femoral head in THA.</p><p><strong> </strong></p></div>