Aims. Though most humeral shaft fractures heal nonoperatively, up to one-third may lead to nonunion with inferior outcomes. The Radiographic Union Score for HUmeral Fractures (RUSHU) was created to identify high-risk patients for nonunion. Our study evaluated the RUSHU’s prognostic performance at six and 12 weeks in discriminating nonunion within a significantly larger cohort than before. Methods. Our study included 226 nonoperatively treated humeral shaft fractures. We evaluated the interobserver reliability and intraobserver reproducibility of RUSHU scoring using intraclass correlation coefficients (ICCs). Additionally, we determined the optimal cut-off thresholds for predicting nonunion using the receiver operating characteristic (ROC) method. Results. The RUSHU demonstrated good interobserver reliability with an ICC of 0.78 (95% CI 0.72 to 0.83) at six weeks and 0.77 (95% CI 0.71 to 0.82) at 12 weeks. Intraobserver reproducibility was good or excellent for all analyses. Area under the curve in the ROC analysis was 0.83 (95% CI 0.77 to 0.88) at six weeks and 0.89 (95% CI 0.84 to 0.93) at 12 weeks, indicating excellent discrimination. The optimal cut-off values for predicting nonunion were ≤ eight points at six weeks and ≤ nine points at 12 weeks, providing the best specificity-sensitivity trade-off. Conclusion. The RUSHU proves to be a reliable and reproducible radiological scoring system that aids in identifying patients at risk of nonunion at both six and 12 weeks post-injury during non-surgical treatment of humeral shaft fractures. The statistically optimal cut-off values for predicting nonunion are ≤ eight at six weeks and ≤ nine points at 12 weeks post-injury

Aims. The primary aim was to estimate the cost-effectiveness of routine operative fixation for all patients with humeral shaft fractures. The secondary aim was to estimate the health economic implications of using a Radiographic Union Score for HUmeral fractures (RUSHU) of < 8 to facilitate selective fixation for patients at risk of nonunion. Methods. From 2008 to 2017, 215 patients (mean age 57 yrs (17 to 18), 61% female (n = 130/215)) with a nonoperatively managed humeral diaphyseal fracture were retrospectively identified. Union was achieved in 77% (n = 165/215) after initial nonoperative management, with 23% (n = 50/215) uniting after surgery for nonunion. The EuroQol five-dimension three-level health index (EQ-5D-3L) was obtained via postal survey. Multiple regression was used to determine the independent influence of patient, injury, and management factors upon the EQ-5D-3L. An incremental cost-effectiveness ratio (ICER) of < £20,000 per quality-adjusted life-year (QALY) gained was considered cost-effective. Results. At a mean of 5.4 yrs (1.2 to 11.0), the mean EQ-5D-3L was 0.736 (95% confidence interval (CI) 0.697 to 0.775). Adjusted analysis demonstrated the EQ-5D-3L was inferior among patients who united after nonunion surgery (β = 0.103; p = 0.032). Offering routine fixation to all patients to reduce the rate of nonunion would be associated with increased treatment costs of £1,542/patient, but would confer a potential EQ-5D-3L benefit of 0.120/patient over the study period. The ICER of routine fixation was £12,850/QALY gained. Selective fixation based on a RUSHU < 8 at six weeks post-injury would be associated with reduced treatment costs (£415/patient), and would confer a potential EQ-5D-3L benefit of 0.335 per ‘at-risk patient’. Conclusion. Routine fixation for patients with humeral shaft fractures to reduce the rate of nonunion observed after nonoperative management appears to be a cost-effective intervention at five years post-injury. Selective fixation for patients at risk of nonunion based on their RUSHU may confer even greater cost-effectiveness, given the potential savings and improvement in health-related quality of life. Cite this article: Bone Jt Open 2022;3(7):566–572

Aims. The primary aim of this study was to develop a reliable, effective radiological score to assess the healing of humeral shaft fractures, the Radiographic Union Score for HUmeral fractures (RUSHU). The secondary aim was to assess whether the six-week RUSHU was predictive of nonunion at six months after the injury. Patients and Methods. Initially, 20 patients with radiographs six weeks following a humeral shaft fracture were selected at random from a trauma database and scored by three observers, based on the Radiographic Union Scale for Tibial fractures system. After refinement of the RUSHU criteria, a second group of 60 patients with radiographs six weeks after injury, 40 with fractures that united and 20 with fractures that developed nonunion, were scored by two blinded observers. Results. After refinement, the interobserver intraclass correlation coefficient (ICC) was 0.79 (95% confidence interval (CI) 0.67 to 0.87), indicating substantial agreement. At six weeks after injury, patients whose fractures united had a significantly higher median score than those who developed nonunion (10 vs 7; p < 0.001). A receiver operating characteristic curve determined that a RUSHU cut-off of < 8 was predictive of nonunion (area under the curve = 0.84, 95% CI 0.74 to 0.94). The sensitivity was 75% and specificity 80% with a positive predictive value (PPV) of 65% and a negative predictive value of 86%. Patients with a RUSHU < 8 (n = 23) were more likely to develop nonunion than those with a RUSHU ≥ 8 (n = 37, odds ratio 12.0, 95% CI 3.4 to 42.9). Based on a PPV of 65%, if all patients with a RUSHU < 8 underwent fixation, the number of procedures needed to avoid one nonunion would be 1.5. Conclusion. The RUSHU is reliable and effective in identifying patients at risk of nonunion of a humeral shaft fracture at six weeks after injury. This tool requires external validation but could potentially reduce the morbidity associated with delayed treatment of an established nonunion. Cite this article: Bone Joint J 2019;101-B:1300–1306