Muscle versus Fascia Free Tissue Transfer for Treatment of Chronic Osteomyelitis in the Comorbid Population

Abstract

Objective: In patients with chronic lower extremity (LE) wounds, chronic osteomyelitis confers additional complexity to achieving adequate treatment. Previous reviews demonstrate increased rates of osteomyelitis recurrence in patients who receive muscle flaps compared to fasciocutaneous flaps for LE limb salvage; however, these studies were not limited to atraumatic populations who receive exclusively free flaps. Thus, this study compared rates of recurrence in chronic osteomyelitis patients undergoing LE reconstruction with fasciocutaneous versus muscle free flaps. Methods: Patients undergoing FTT between July 2011 and July 2021 were retrospectively reviewed. Patients were stratified into fasciocutaneous and muscle free flap groups. Primary outcomes included osteomyelitis recurrence, flap complications, limb salvage, and ambulatory status. Results: Forty-eight patients with pathologic diagnosis of chronic osteomyelitis of the wound bed were identified, of which 58.3% received fasciocutaneous (n=28) and 41.7% received muscle flaps (n =20). The most common comorbidities included diabetes mellitus (n=29, 60.4%), peripheral neuropathy (n=27, 56.3%) and peripheral vascular disease (n=24, 50.0%). Methicillin-resistant or -sensitive Staphylococcus aureus were the most common pathogen in 18.7% (n=9) of procedures. The majority of patients underwent a median of three debridements followed by NPWT prior to receiving FTT. At a median follow-up of 14.6 months, the limb salvage and ambulatory rates were 79.2% (n=38) and 83.3% (n=40), respectively. The overall rate of microsurgical flap success was 93.8% (n=45). Osteomyelitis recurred in 25% of patients (n=12) at a median duration of 4.0 months. There were no significant differences in rates of osteomyelitis recurrence, flap complications, limb salvage, ambulation, and mortality. On multivariate analysis, flap composition remained a nonsignificant predictor of osteomyelitis recurrence (OR 0.975, p=0.973). Conclusion: This study demonstrates that flap composition may not influence recurrence of osteomyelitis following free flap reconstruction of chronic lower extremity wounds, suggesting that optimal flap selection should be based on wound characteristics and patient goals.