Dysplasia_Clinical.xlsx

<b>Abstract</b> <i>Background:</i> Arthritis secondary to developmental hip dysplasia often mandates implant surgery at a relatively young age. Hip resurfacing arthroplasty (HRA), compared with standard stemmed total hip arthroplasty (THA), affords a more active lifestyle including extreme-motion activities but stimulates concerns pertaining to implant failure. <i>Methods:</i><b> </b>We addressed the primary modes of failure through a series of interventions, including a new guideline for achieving proper implant alignment through intraoperative x-rays. We then compared two sequential cohorts in a single-surgeon practice: patients with developmental dysplasia who underwent HRA before (Group 1; 121 hips in 105 patients) and after (Group 2; 242 hips in 210 patients) June 2008, at which time the four interventions were all in place. <i>Results: </i>Implants in Group 2 failed less frequently within two years (0.8% vs. 6.6%, p = 0.002) and were more likely to have projected seven-year Kaplan-Meier survivorship (99% vs. 89%, p &lt; 0.0001 by log-rank test). Patients in Group 2 were more likely to have normal metal ion levels (77% vs. 56%, p = 0.0008) and optimum metal ion levels (99% vs. 86%, p = 0.0008). Patients in Group 2 also benefited from a 19-minute decrease in mean operation time, a 45% decrease in mean estimated blood loss, and a 0.9-day decrease in mean hospital stay (p &lt; 0.0001 in each instance). <i>Conclusions: </i>We believe the interventions reported here, combined with sufficient surgeon experience and properly designed implants, afford patients with developmental dysplasia a more active lifestyle with favorable implant survival.