Clinical outcomes of the limb reconstruction system in knee arthrodesis

Knee arthrodesis is an established salvage procedure for irreparable knee conditions, particularly chronic periprosthetic joint infection (PJI) and advanced septic arthritis. External fixation using the limb reconstruction system (LRS) is advantageous in infected scenarios due to its extraosseous placement and facilitation of soft tissue care. This study evaluates the clinical, radiological and functional outcomes of anterolateral LRS fixation in septic knees.

This retrospective observational study included 16 patients who underwent knee arthrodesis with anterolateral LRS fixation over 5 years. Indications were chronic PJI (n = 13) and septic arthritis (n = 3). All patients underwent single-stage debridement, fibular strut grafting, antibiotic-augmented grafting and LRS application. Postoperative management included tailored antibiotics, compression, and structured rehabilitation. Outcomes were assessed with radiographs, visual analogue scale (VAS), lower extremity functional scale (LEFS), Knee Society score (KSS), SF-36 physical component score (PCS), and satisfaction surveys.

Radiographic fusion occurred in 14 of 16 patients (87.5%) at a mean of 10.2 months and 2 patients developed persistent infection and non-union. Mean VAS scores improved from 7.8 preoperatively to 2.1 postoperatively (p < 0.001). The LEFS averaged 48.2, KSS 71.5, and SF-36 PCS improved from 34.8 to 63.4. Of the patients 75% were "very satisfied" with the outcome. Mean limb shortening was 4.5 cm, managed with shoe raises.

Anterolateral LRS application for knee arthrodesis in septic knees provides high fusion rates, substantial pain relief, and acceptable functional recovery, with low complication rates, making it a reliable salvage option.