Validity and reliability of the osteoporotic fracture treatment score (OF score) and outcomes across various treatments in osteoporosis vertebral compression fracture patients

Background Osteoporotic vertebral compression fractures (OVF) are prevalent and substantially impact healthcare systems and patients' quality of life. The osteoporotic fracture treatment score (OF score), developed by the German Society of Orthopedics and Trauma (DGOU), guides surgical decisions, but its reliability and validity are underexplored. This study assessed the OF score's inter- and intraobserver reliability, validated its treatment recommendations, and investigated intermediate outcomes of different DGOU-recommended surgical strategies for OVF. Methods A retrospective cohort study was conducted. Inter- and intraobserver reliability of the OF score and its subcomponents were analyzed using clinical and radiographic data. Validity was assessed by comparing the OF score's recommended treatments with actual treatments received. Outcomes at the final follow-up were back pain visual analog scale, Oswestry Disability Index, EQ-VAS, EQ-5D-5 L, adjacent fracture incidence, local kyphotic angle, and reoperation rates. Patients with at least 1-year follow-up were included. Results A total of 157 patients (84.7% female; mean age 74.2 +/- 10.5 years) were evaluated. The most frequent osteoporotic fracture (OF) types were OF4 (49.0%) and OF3 (40.8%). The OF score demonstrated good interobserver reliability (ICC = 0.77, 95% CI: 0.65-0.86) and intraobserver reliability (ICC = 0.83, 95% CI: 0.72-0.90). Kappa values for subcomponents ranged from 0.57 to 0.89. Excluding patients with indeterminate recommendations (OF score = 6), 82.9% received treatments concordant with OF score recommendations. Receiver operating characteristic curve analysis showed an area under the curve of 0.77 (95% CI: 0.67-0.86); an OF score cutoff > 6.5 predicted actual treatment with 87.9% sensitivity and 61.0% specificity. All surgical treatments showed comparable improvements in clinical outcomes. However, patients treated with stand-alone cement augmentation (CA) had less local kyphotic angle correction (P = 0.004) and greater postoperative kyphotic progression (P < 0.001) than those undergoing short-segment (SS-PI) or long-segment instrumentation (LS-PI). No significant differences in adjacent fractures or complications were observed. Conclusions The OF score is a reliable and valid system with good discriminative ability for surgical decision-making in OVF patients. CA, SS-PI, and LS-PI are viable options with comparable functional outcomes. However, in OF3 or OF4 fractures, caution is advised due to lesser kyphosis correction and greater kyphotic progression with CA compared to SS-PI or LS-PI, as recommended by the DGOU.