Long-term clinical and radiological outcomes following non-union surgery: ongoing remodeling and improvement in clinical findings after five years

BACKGROUND: Non-unions after fractures are known to be a devastating complication in trauma surgery and studies assessing long-term patient-reported, clinical, and radiological outcome measures are scarce. Most evidence-based research on non-unions and their long-term follow-up evaluate the first two post-operative years while excluding subsequent years and their impact on the overall outcome. This study aimed to evaluate the functional, clinical and radiological outcomes five years post-operative. METHODS: In this prospective study, all patients treated operatively between June 2018 and December 2020 for non-unions including every site were systematically reviewed for inclusion and summoned for a follow-up after 5 years. The outcome was evaluated using the modified Lane-Sandhu-Score (LSS), the short-form 12 (SF-12), active range of motion (ROM) and visual analogue scale (VAS). Furthermore, data on complications was collected. For all analyses, a p-value < 0.05 was evaluated as significant. RESULTS: A total of 45 patients were included in the study with a follow-up time of 63 months (IQR: 55; 66). The LSS median after five years was 4 (IQR: 4; 4) and of the VAS 0 (IQR: 0; 4). 95.6% of patients were satisfied with the therapy after five years. Regarding the SF-12, the median score for the mental component was 55.2 (IQR: 48.7; 58.8) and the physical component averaged at 44 ± 10.84. From the second to the fifth post-operative year, patients showed significant improvements in the LSS (Z = - 4.334, p < 0.0001). Additionally, improvements in VAS (3 [IQR: 0.5; 4.5] at one year vs. 0 [IQR: 0; 4.5] at five years; p = 0.008) as well as quality of life (SF12m median at 1 year 54.05 [IQR: 47.4; 57.05] vs. SF-12 m median at 5 years 56.2 [IQR: 50.7; 57.6, p = 0.08]; mean SF-12p at 1 year 42.77 ± 9.15 vs. mean SF-12p at 5 years 45.4 ± 9.91, p = 0.0468) were evident. 31% of the patients experienced an improvement in ROM compared to the last follow-up. CONCLUSION: This study demonstrates that even beyond the second postoperative year, significant progress in both radiological and clinical findings continues. As a result, patients with non-unions should continue to be examined in special out-patient clinics even after completing the first two years of follow-up.