Abstract
HIGHLIGHTS: What are the main findings? Single-stage threaded antibiotic-coated locking nails were associated with 96.7% short-term infection control and 90.0% radiographic union at 6 months in 30 patients with osteomyelitis-associated long-bone nonunion. Pain, EQ-5D-5L, and return to work all improved substantially by Month 6, and no cement debonding, implant failure, or nephrotoxicity was observed. What are the implications of the main findings? These short-term findings suggest a pragmatic single-stage option for infected long bone non-union in resource-constrained, high-MDR/XDR settings. The independent contribution of the threaded core cannot be established from this single-arm study; therefore, larger comparative trials with longer follow-up are needed. ABSTRACT: Background: Long-bone non-unions complicated by osteomyelitis remain a major reconstructive and healthcare challenge, particularly in resource-limited settings with a high prevalence of multidrug-resistant (MDR) pathogens. Conventional staged management is associated with a prolonged treatment burden, repeated procedures, and delayed functional recovery. This study evaluated the clinical, radiological, functional, and short-term safety outcomes of a single-stage approach using custom-threaded antibiotic-coated locking nails (TACLNs) in a high-resistance cohort. Methods: This prospective single-center cohort study enrolled 30 adults with osteomyelitis-associated femoral or tibial nonunion at a tertiary hospital in Peshawar, Pakistan. All patients underwent radical debridement and single-stage stabilization with a chest tube mold TACLN loaded with vancomycin and gentamicin, with culture-directed adjunctive antibiotics for resistant organisms. Outcomes were assessed at baseline, Weeks 3 and 6, and Month 6 using inflammatory markers, RUST score, VAS pain, EQ-5D-5L, ASAMI criteria, and return to work or usual activity. No formal sample size calculation was performed, and this study was exploratory in nature. Results: The cohort (mean age 44.9 ± 9.9 years) had a challenging microbiological profile, with 40.0% MDR and 13.3% extensively drug-resistant (XDR) infections. By Month 6, short-term infection control was achieved in 96.7% of patients, with significant reductions in ESR and CRP (both p < 0.001). Radiographic union was achieved in 90.0% of cases at a mean of 18.6 weeks, and the mean RUST score improved from 4.87 to 10.43 at the final follow-up. The VAS pain decreased from 5.23 at week 3 to 0.73 at month 6, EQ-5D-5L improved from 0.39 to 0.84, and 90.0% returned to work or usual activity by month 6. No cement debonding, implant failure, or nephrotoxicity was noted. Conclusions: In this single-arm exploratory cohort, TACLNs were associated with favorable short-term infection control, radiographic union, and functional recovery in osteomyelitis-associated long-bone nonunion, including in an MDR/XDR setting. The independent contribution of the threaded core design cannot be established. Larger multicenter comparative studies with longer follow-ups are needed to confirm the durability and implementation feasibility.