Influence of surgical experience in the learning curve of a new approach in hip replacement: anterior mini-invasive vs. standard lateral.

There is conflicting evidence regarding the potential benefit of minimally invasive surgery for total hip arthroplasty (THA), especially during the 'learning curve' of individual surgeons. Sixty patients who underwent THA between January and December 2010 were evaluated. The aim was to assess the anterior mini-invasive (MI) approach performed in 30 patients during the learning curve of a single experienced hip surgeon compared with the results of 30 patients operated upon through a standard lateral approach by the same surgeon. Operation and hospitalisation times, blood loss, number of transfusions, peri-operative complications and femoral/acetabular component placement were monitored. Harris Hip Score (HHS) and Hip Disability and Osteoarthritis Outcome Score (HOOS) were analysed before and 12 months after surgery. Pain Visual Analogue Scale (VAS) was also recorded 1 week and 1 month after surgery. Hospitalisation, blood loss, number of transfusions and VAS score 1 week postoperatively were significantly lower and operative time was significantly longer in the anterior MI approach. Similar functional outcomes 1 year after surgery, component positioning and complication rates were observed in both groups. The results suggest that anterior MI approach is a safe procedure during the learning curve of an experienced hip surgeon.