Metal on Metal Resurfacing Hip Arthroplasty for Hip Arthritis : A Short Term Outcome Analysis

INTRODUCTION: Arthroplasty is an operation to restore pain free motion to a joint and function to the muscles, ligaments and other sort tissue structures that control the joint. The goals of total joint arthroplasty are to relieve pain, to provide motion while maintaining stability and to correct deformity. Pain in the hip joint is one of the most common causes in disabling human locomotion. Pain in the hip may be due to various causes and there are many ways of treating it. Analgesics, arthrodesis, osteotomy, excision arthroplasty, and replacement arthroplasty are some of them. Total Hip Arthroplasty is the most commonly performed adult reconstructive hip procedure. Implanting artificial femoral head and acetabular socket to replace the degenerated/ destroyed hip joint will relieve the pain and provides pain free, mobile and stable joint. AIM: The aim of this study is to analyze the short term follow up of functional results of twelve resurfacing hip arthroplasties prospectively, done using ICON articular surface replacement prosthesis done in our Institute during the period June 2006 to August 2008. MATERIALS AND METHODS: This is a prospective study conducted at Department of Orthopaedics, Government General Hospital from June 07 to October 08. We had done 12 metal on metal resurfacing hip arthroplasty on 10 patients for various indications. Preoperative planning - The resurfacing hip arthroplasty is an elective surgery. A thorough preoperative evaluation is done. The indication for surgery, level of pain and disability, response to conservative therapy and the patient’s expectations of results are reviewed. Informed consent was obtained from all the patients. The general condition of the patient including his physical and mental status, general medical condition and ability to withstand the surgery are analyzed. Physical examination includes besides the affected hip, the contralateral hip, spine and both knees. Any limb length discrepancy, fixed deformities and the available range of movements are noted. Abductor mechanism and stability of the hip are assessed. RESULTS: In the study period, twelve hips were operated in ten patients. The age range was 17-40 years, average 26.3. There were 8 male patients and 2 female patients. Those females who were desirous of childbirth were excluded from the study and were offered other forms of treatment. The diagnosis leading to surgery was inflammatory arthritis in 5 patients (Juvenile ankylosing Spondylitis in 2 patients, Juvenile Rheumatoid Arthritis in 2 patients, Rheumatoid Arthritis in 1 patient) and secondary degenerative arthritis in 5 patients (secondary to AVN in 4 patients and post traumatic in 1 patient). Functional results - Of the ten patients, nine returned to premorbid function, eight being employed in their previous occupation and one patient has returned to school. One patient with Juvenile ankylosing Spondylitis is incapacitated by back pain. CONCLUSION: The mean pre-operative Harris Hip Score was 48.5, while the mean post-operative Harris Hip Score was 93.9, indicative of the overall excellent short-term clinical outcome. We conclude that surface arthroplasty is a viable alternative to total hip arthroplasty, especially in young individuals, with excellent short-term clinical outcome. As this is only a short term study, further follow up and evaluation with more number of patients is essential to come out with a definitive conclusion.