Aims: The aim of this study was to evaluate the radiological outcome of patients with large bone defects in the femur and tibia who were treated according to the guidelines of the diamond concept in our department (Centre for Orthopedics, Trauma Surgery, and Paraplegiology).Methods: The following retrospective, descriptive analysis consists of patients treated in our department between January 2010 and December 2021. In total, 628 patients were registered, of whom 108 presented with a large-sized defect (≥ 5 cm). A total of 70 patients met the inclusion criteria. The primary endpoint was radiological consolidation of nonunions after one and two years via a modified Lane-Sandhu Score, including only radiological parameters.Results: The mean defect size was 6.77 cm (SD 1.86), with the largest defect being 12.6 cm. Within two years after surgical treatment, 45 patients (64.3%) presented consolidation of the previous nonunion. After one year, six patients (8.6%) showed complete consolidation and 23 patients (32.9%) showed a considerable callus formation, whereas 41 patients (58.6%) showed a Lane-Sandhu score of 2 or below. Two years after surgery, 24 patients (34.3%) were categorized as Lane-Sandhu score 4, another 23 patients (32.9%) reached a score of 3, while 14 patients (20.0%) remained without final consolidation (score ≤ 2). A total of nine patients (12.9%) missed the two-year follow-up. The mean follow-up was 44.40 months (SD 32.00). The mean time period from nonunion surgery to consolidation was 16.42 months (SD 9.73)Conclusion: Patients with presentation of a large-sized nonunion require a structured and sufficiently long follow-up to secure the consolidation of the former nonunion. Furthermore, a follow-up of at least two years is required in order to declare a nonunion as consolidated, given that a significant part of the nonunions declared as not consolidated at one year showed consolidation within the second year. Moreover, the proven “gold standard” of a two-step procedure, so called Masquelet technique, shows effectiveness.Cite this article: Bone Jt Open 2024;6(1):26–34.

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.