Using 3D printing-assisted shaping titanium cages and Masquelet techniques to reconstruct calcaneal osteomyelitis complicated by extensive soft tissue and uncontrolled defects

Objective: To investigate the clinical efficacy of three-dimensional (3D) printing-assisted shaping titanium cage combined with Masquelet technology in the treatment of calcaneal infectious defects. Methods: A retrospective analysis was performed of the data from nine patients with chronic calcaneal infection defects treated with distal gastronal flap coverage and one patient with free anterolateral thigh flap coverage, also using a 3D printing-assisted shaping titanium cage combined with both mask technology and rib autografting from January 2017 to January 2019. There were seven males and three females, with a mean age of 37 years (range, 17-52 years). The injury mechanism of the 10 patients included four motor vehicle incidents, four high fall injuries, and two rolling compactions. All patients were treated by two-stage procedures. The first stage included debridement, polymethyl methacrylate (PMMA) filling, and regional flap coverage. The soft tissue defect of the 10 cases included 80 cm2 in four cases and 56 cm(2), 40 cm(2), and 15 cm(2) in each of two cases. The bone defect was 24 cm(3) and 18 cm(3) in each of four cases and 3 cm(3) in two cases. The second stage was the mask technology of 3D printing-assisted shaping titanium cage combined with rib autografting. Time of bone union, calcaneus morphology, implant position, and the Maryland and AOFAS hind foot scores were recorded to evaluate the clinical outcome. Results: All 10 patients were followed up for a mean of 18.5 months (range, 12-30 months). Infection occurred in two patients 2 months after the first stage operation and were successfully treated by debridement and PMMA replacement. The incision of the other eight cases all healed successfully. Cultures from the 10 cases included five cases of methicillin-resistant Staphylococcus aureus, three cases of S. aureus, and one case each of Escherichia coli and Pseudomonas aeruginosa. All 10 patients exhibited calcaneus bone union after the second stage operation. The mean time for bone union was 4.32 (range, 3-8) months. Bone trabeculae were observed in a CT scan 13 (range, 10-22) months post-operation. The mean Maryland score at 12 months post-operation was 92 (range, 86-98) and the mean AOFAS ankle hind foot score was 89.8 (range, 83-100). Conclusion: Three-dimensional printing-assisted shaping titanium cages and Masquelet technology may be effective methods for the treatment of infectious calcaneal defects.