THE PEARL-STRING TECHNIQUE FOR RECONSTRUCTION OF LARGE BONY DEFECTS FOLLOWING OSTEOMYELITIS: EARLY RESULTS FROM A TERTIARY REFERRAL CENTRE

Introduction & Aim Reconstruction of large bony defects following destructive osteomyelitis remains one of the most demanding challenges in orthopaedic infection surgery. The Induced Membrane Technique (IMT), originally described by Masquelet, is an established two-stage approach but carries heterogeneous outcomes and known limitations. The Pearl-String Technique (PST), recently introduced by the a hospital in the centre of Germany, represents an innovative modification of the IMT combining thermodisinfected, decorticated femoral heads arranged in a pearl-string configuration, covered by autologous cancellous bone graft, with a mechanically stable internal osteosynthesis, emphasising primary stability and osteoconductive scaffolding. This study aims to report our early experience adopting the PST in a tertiary referral centre specialising in orthopaedic infection surgery. Methods Between June 2025 and April 2026 18 consecutive patients with bony defects secondary to acute or chronic osteomyelitis of the long bones and foot were treated using the PST. The surgical protocol followed the principles of the IMT: radical debridement and resection of infected bone, temporary stabilisation with external fixation and a polymethyl methacrylate (PMMA) spacer impregnated with antibiotics in stage one, followed by spacer removal and reconstruction using the PST in stage two. Bony defects ranged from 3 to 16 cm. Targeted antibiotic therapy was administered in all cases. Outcomes assessed included infection eradication, radiological bone healing, time to consolidation, complications, and re-operation rate. Follow-up ranged from 6 to 12 months. Results Infection eradication was achieved in all patients at the time of reporting. Progressive bone consolidation was demonstrated radiologically across the cohort, with healing ongoing at final follow-up in several patients consistent with the expected biological timeline of the technique. Two complications were recorded: one intramedullary nail failure requiring revision, and one case of persistent wound infection following the reconstructive stage requiring further surgical management. No amputations were performed. Conclusions Early adoption of the PST in a high-volume infection orthopaedics centre is feasible and reproducible. Preliminary results demonstrate encouraging infection eradication rates and progressive bone regeneration comparable to published IMT data. The PST offers the potential advantage of high primary mechanical stability combined with an osteoconductive scaffold. Larger case series with longer follow-up are needed to validate these findings.