Application of Staged Negative Pressure Wound Therapy and Flap Surgery for Infection Control After Patellar Internal Fixation Surgery

The anatomic position of the patella is superficial, making it vulnerable to injuries. Treatment of patella infection after internal fixation surgery remains a big challenge due to minimal soft tissue coverage and vital tissue exposure. Forty-two patients aged 10 to 59 years were admitted to the institution's burn unit between January 2010 and December 2019. Each presented with infection after patellar fracture surgery. Twenty-seven infections were superficial, whereas 15 were deep with pyogenous arthritis of the knee. Negative pressure wound therapy (NPWT) was applied after radical debridement to remove necrotic subcutaneous tissues and internal fixation devices. In addition, cases with septic arthritis were irrigated continuously with normal saline. After 5 to 10 days of NPWT treatment and irrigation, wound infection was well controlled. Afterward, 42 wounds were resurfaced with pedicled flaps, the 42 patients received 17 reverse-flow anterolateral thigh (ALT) perforator flap, 12 medial sural artery perforator flaps, 7 gastrocnemius musculocutaneous flaps, as well as 6 saphenous artery flaps. Thirty-seven flaps survived uneventfully. However, 3 flaps developed venous congestion in the distal end. Two flaps developed tip necrosis. All patients were followed up between 3 and 48 months. Infection beneath the flap occurred in 3 patients and healed after an additional debridement surgery. The staged NPWT and flap surgery strategy focus on thorough debridement and immediate internal fixation devices removal, effective fracture fixation, efficient NPWT application, targeted administration of antibiotics, and adequate soft tissue coverage. This study established that the procedure was effective in infection control after patellar internal fixation surgery.