Functional recovery, complications and CT positioning of total hip replacement performed through a Rottinger anterolateral mini-incision. Review of a continuous series of 103 cases

Introduction: Minimally invasive approaches entail an increased risk of malpositioning and perioperative complications. Most studies analyzed these data only on plain X-ray rather than computed tomodensitometry (CT) in assessing implant positioning. Hypothesis: A Rottinger minimally invasive anterolateral (MIS-AL) approach provides rapid complication-free functional recovery with reliable implant positioning on CT-scan. Patients and method: One hundred and three primary cemented total hip replacements (THR) performed by a single surgeon using a MIS-AL approach underwent clinical assessment at six weeks and three, six and 12 months on X-ray, including CT and postoperative myoglobinemia and creatine phosphokinase (CPK). Results: Pain, on a visual analog scale, was graded less than 1 at 36 hours; canes ceased to be used at a mean three weeks; and mean Postel-Merle-D'Aubigne, score at six months was 17.36 (range, 13-18). There were ten approach-related complications (9.7%: one femoral perforation, two dislocations, two femoral neck fissures, two cases of meralgia paresthetica and three of tensor tendinitis). Mean CPK level was 390.9 +/- 252 mu g/L (range, 88-1095 mu g/L) at 24 hr post-operatively and 319 +/- 256 mu g/L (95-1028 mu g/L) at 48 hr. Mean postoperative myoglobinemia was 299 +/- 152.6 mu g/L (75-914 mu g/L). Mean acetabular inclination and anteversion on CT were respectively 44.7 degrees +/- 4.6 degrees (34 degrees-56 degrees) and 9.2 degrees +/- 9.2 degrees (-17 degrees-35 degrees) and mean femoral anteversion 23.5 degrees +/- 9.4 degrees (2 degrees-53 degrees). Discussion: Functional recovery was quick, but with an 8.7% complications rate (excluding four cases of spontaneously resolved tendon pain). CT showed reliable cup positioning, but a wide scatter in femoral anteversion. Elevated muscle enzyme levels possibly testified to approach-related tissue attrition. The MIS-AL approach involves a learning curve to avoid femoral perforation. It provided rapid functional recovery with reliable positioning, at least for the cup, and a low rate of associated complications. Level of evidence: III, prospective continuous study. (C) 2011 Elsevier Masson SAS. All rights reserved.