Postoperative changes in the tensor fascia lata muscle after using the modified anterolateral approach for total hip arthroplasty.

The modified Watson-Jones approach to the hip has been described as a minimally invasive approach with the potential for fewer postoperative complications than the traditional approach. Because the approach relies on an intermuscular rather than an internervous plane, there is potential for injury to the superior gluteal nerve. The aim of this study was to evaluate incidence of tensor fascia lata (TFL) denervation in patients undergoing this approach. Twenty-six patients underwent total hip arthroplasty (THA) using a modified anterolateral approach. Postoperative MRIs were analyzed for signs of muscle denervation including atrophy, hypertrophy and fat replacement. At a median follow-up of 9.3months, 74% of patients exhibited either atrophy or hypertrophy of the TFL and 42% exhibited fat replacement on MRI.

Stasis predisposes ileal pouch inflammation in a rat model of ileal pouch-anal anastomosis.

BACKGROUND: While restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) has become the definitive surgical treatment for patients suffering from chronic ulcerative colitis (CUC), pouchitis still remains a major late complication. Fecal stasis has been implicated in the etiology of ileal inflammation; however, the mechanism(s) remain unclear, in part due to the lack of an animal model. Our goal was to surgically mimic the IPAA procedure in a rat to investigate the hypothesis that stasis leads to biochemical changes that predispose the ileal pouch to inflammation. MATERIALS AND METHODS: Thirty-two Sprague-Dawley rats underwent total colectomy with either straight ileorectal (IRA) or IPAA, and 11 nonoperated rats served as controls (Controls). Twenty-one d postoperatively, 48 h serial barium radiographs and 12 h charcoal transit follow-through studies were performed. Following sacrifice, ileal tissue was harvested for the measurement of myeloperoxidase activity (MPO) activity, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) mRNA levels, and histology. RESULTS: Serial barium radiographs showed stasis in the ileal pouch compared with IRA animals, and charcoal transit times that were two times longer (P ≤ 0.05) than that in the straight IRA rats. Ileal pouch MPO levels were significantly elevated in the IPAA rats compared with the straight IRA rats. ICAM-1 and VCAM-1 mRNA levels were not associated with neutrophil infiltration. CONCLUSIONS: These studies showed that ileal pouch stasis predisposes biochemical and histological evidence of ileal pouch mucosal inflammation. Studies such as this may provide the rationale for novel, adjunct therapies for the management of pouchitis in patients having undergone IPAA for CUC.