The purpose of this study was to examine our experience with this flap for the treatment of recalcitrant nonunions of the extremities. A retrospective chart review was performed on 11 consecutive patients treated with the medial femoral periosteal bone flap from June 2003 to March 2005. Patient demographics, nonunion characteristics, complications, and long-term outcome based on radiographic and clinical parameters were analyzed. Nine free transfers and 3 pedicled flaps were used for a total of 12 nonunion sites in 11 patients. The average age of the patient population was 49 years (21-64 years). The location of the nonunion sites were femur (n = 4), tibia (n = 2), humerus (n = 3), clavicle (n = 2), and radius (n = 1). The nonunion sites were secondary to traumatic fractures complicated by osteomyelitis (n = 10) and tumor extirpation (n = 2). The time period of nonunion prior to the use of vascularized periosteal bone graft ranged from 10 months to 23 years (median = 23 months). All patients had previous attempts at debridement with or without antibiotic bead placement, and all underwent rigid fixation with or without nonvascularized bone grafts prior to vascularized grafting. Following flap placement, 9 (75%) of the nonunion sites healed primarily without complication at an average period of 3.8 months (2-7 months). Two nonunions healed secondarily following hardware modification. There was only 1 flap failure secondary to arterial thrombosis, resulting in a below-knee amputation. The rate of limb salvage was 91%. Donor-site morbidity was minimal, with postoperative seromas occurring in 3 patients.

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Insulin resistance is associated with obesity but mechanisms controlling this relationship in humans are not fully understood. Studies in animal models suggest a linkage between adipose reactive oxygen species (ROS) and insulin resistance. ROS oxidize cellular lipids to produce a variety of lipid hydroperoxides that in turn generate reactive lipid aldehydes that covalently modify cellular proteins in a process termed carbonylation. Mammalian cells defend against reactive lipid aldehydes and protein carbonylation by glutathionylation using glutathione-S-transferase A4 (GSTA4) or carbonyl reduction/oxidation via reductases and/or dehydrogenases. Insulin resistance in mice is linked to ROS production and increased level of protein carbonylation, mitochondrial dysfunction, decreased insulin-stimulated glucose transport, and altered adipokine secretion. To assess protein carbonylation and insulin resistance in humans, eight healthy participants underwent subcutaneous fat biopsy from the periumbilical region for protein analysis and frequently sampled intravenous glucose tolerance testing to measure insulin sensitivity. Soluble proteins from adipose tissue were analyzed using two-dimensional gel electrophoresis and the major carbonylated proteins identified as the adipocyte and epithelial fatty acid–binding proteins. The level of protein carbonylation was directly correlated with adiposity and serum free fatty acids (FFAs). These results suggest that in human obesity oxidative stress is linked to protein carbonylation and such events may contribute to the development of insulin resistance.