Chon J, et al. Clin Orthop Surg. 2016 Jun;8(2):157-163. http://dx.doi.org/10.4055/cios.2016.8.2.157

Background: Subchondral cysts at the ulnar corner of the lunate are frequently encountered in patients with distal radius fractures. We hypothesized that the presence of these lunate subchondral cysts may be associatedwith decreased cortical bone density due to limited load translation. Consequently, this could lead to lunate fossa collapse and increased ulnar variance following fracture fixation. Methods: A retrospective analysis was performed on 176 patients who underwent open reduction and internal fixation using the Double-tiered Subchondral Support (DSS) procedure between May 2014 and June 2017. Twenty-eight patients identified with lunate subchondral cysts on preoperative CT scans were selected as the study group. A control group of 28 patients without cysts was selected using matched-pair analysis, controlling for gender, age, fracture classification, and follow-up period. Results: The mean change (delta) in ulnar variance was 0.191 mm in the cyst group, which was less than the 0.233 mm observed in the control group; however, this difference was not statistically significant (p = 0.557). Regarding ulnolunate distance, the cyst group showed a mean change (delta) of 0.991 mm, while the control group showed a change of 1.123 mm. This difference was also not statistically significant (p = 0.681). Conclusions: Although it was hypothesized that lunate subchondral cysts might limit load translation to the radius and compromise cortical bone density—potentially affecting fracture healing and the maintenance of reduction—our statistical analysis did not support this hypothesis. The presence of lunate subchondral cysts did not significantly increase the risk of lunate fossa collapse or ulnar variance progression compared to the control group.

Background/Objectives: Cycling-related acetabular fractures have not been well described. We aimed to determine the proportion of acetabular fractures associated with bicycle accidents and to compare their fracture patterns with those caused by other mechanisms. Findings related to clipless pedal use were considered exploratory. Methods: Patients treated for an acetabular fracture between January 2010 and December 2023 were identified by ICD-10 codes from a university hospital network Clinical Data Warehouse. After exclusions, 378 patients with 385 fractures were classified according to the Judet–Letournel system. Fracture-pattern proportions were compared using Fisher’s exact test, and the association with anterior column involvement was examined with logistic regression adjusted for age and sex. Cleat-shoe status, obtained from medical records or telephone interviews, was analyzed descriptively. Results: Bicycle accidents were the mechanism of injury in 26 of 378 patients (6.9%). Compared with fractures caused by other mechanisms, bicycle-related fractures showed a higher proportion of pure anterior column fractures (38.5% versus 16.7%, p = 0.014) and anterior column involvement (65.4% versus 38.2%, p = 0.011). The association with anterior column involvement remained after adjustment for age and sex (adjusted odds ratio 3.02, 95% CI 1.31–6.98). Among 12 confirmed cleat-shoe users, 7 (58.3%) had a pure anterior column fracture, 10 (83.3%) had anterior column involvement, and 8 (66.7%) had extension into the acetabular roof. Conclusions: Bicycle-related acetabular fractures were associated with a higher proportion of anterior column involvement, and the association remained after adjustment for age and sex. Because bone quality and injury energy could not be adjusted for, this association should not be interpreted as causal. The anterior-dominant pattern among confirmed cleat-shoe users is exploratory and should not be interpreted causally.

Background and Objectives: The optimal pharmacological strategy to mitigate progressive vertebral collapse during the acute phase of osteoporotic vertebral compression fractures (OVCFs) remains a subject of debate. This initial 3-month window is the most critical period for evaluating the structural stability of the fracture, as the majority of progressive height loss occurs before solid bone union is achieved, directly influencing the decision to continue conservative management or transition to surgical intervention. Materials and Methods: In this retrospective study, 123 patients were allocated to control (n = 26), denosumab (n = 35), teriparatide (n = 30), or romosozumab (n = 32) groups. Treatment choice was non-randomized, driven by clinical pragmatism and patient preference. Serial changes in vertebral compression rate (VCR) and pain (VAS) were analyzed over 3 months using linear mixed models (LMMs) specifically adjusted for baseline imbalances in initial VCR. Results: In the unadjusted analysis, DMAB appeared to show a slower progression of compression compared to the control group. However, after adjusting for the initial VCR, no significant structural benefit was observed in any medication group (p > 0.05), with all groups showing small effect sizes (Cohen’s d < 0.4). In contrast, unstable fracture morphology was identified as the most potent driver of vertebral collapse (β = 2.758, 95% CI: 1.51–4.01, p < 0.001). Clinically, the RM group showed significantly lower overall pain levels throughout the follow-up period compared to the control group (p = 0.014). Conclusions: Short-term osteoporosis medication does not significantly mitigate vertebral collapse during the acute phase of OVCFs. Practically, these findings suggest that unstable fracture morphology and the baseline VCR—reflecting a potential ‘floor effect’ where less initially collapsed vertebrae may undergo more significant progression—are more informative predictors of acute collapse than medication choice. Consequently, early imaging-based risk stratification is crucial to identify patients at high risk for progressive deformity, regardless of their pharmacological regimen.