Should nails be locked dynamically or statically in atypical femoral fractures? - A radiological analysis of time to union and reoperations in 236 displaced fractures with 4 years average follow-up.

INTRODUCTION: Atypical femoral fractures (AFFs) are associated with delayed union and higher reoperation rates. Axial dynamization of intramedullary nails is hypothesized to reduce time-to-union (TTU) and fixation failure as compared to static locking. METHODS: Consecutive acutely displaced AFFs fixed with long intramedullary nails across five centres between 2006 and 2021 with a minimum postoperative follow-up of three months were retrospectively reviewed. The primary outcome was TTU, compared between AFFs treated with dynamically or statically locked intramedullary nails. Fracture union was defined as a modified Radiographic Union Score for Tibial fractures score of 13 or greater. Secondary outcomes involved revision surgery and treatment failure, defined as non-union beyond 18 months or revision internal fixation for mechanical reasons. RESULTS: A total of 236 AFFs (127 dynamically locked and 109 statically locked) were analysed with good interobserver reliability of fracture union assessment (intraclass correlation coefficient = 0.89; 95% CI = 0.82-0.98). AFFs treated with dynamized nails had significantly shorter median TTU (10.1 months; 95% CI = 9.24-10.96 vs 13.0 months; 95% CI = 10.60-15.40) (log-rank test, p = 0.019). Multivariate Cox regression revealed that dynamic locking was independently associated with greater likelihood of fracture union within 24 months (p = 0.009). Reoperations were less frequent in the dynamic locking group (18.9% vs 28.4%), although the difference was not statistically significant (p = 0.084). Static locking was an independent risk factor for reoperation (p = 0.049), as were varus reduction and lack of teriparatide use within three months of surgery. Static locking also demonstrated a higher frequency of treatment failure (39.4% vs 22.8%, p = 0.006) and was an independent predictor of treatment failure in logistic regression (p = 0.018). Other factors associated with treatment failure included varus reduction and open reduction. CONCLUSIONS: Dynamic locking of intramedullary nails in AFFs is associated with faster time to union, lower rate of non-union, and fewer treatment failures.

Can a Wireless Full-HD Head Mounted Display System Improve Knee Arthroscopy Performance? - A Randomized Study Using a Knee Simulator.

INTRODUCTION: Our prototype wireless full-HD Augmented Reality Head-Mounted Display (AR-HMD) aims to eliminate surgeon head turning and reduce theater clutter. Learning and performance versus TV Monitors (TVM) is evaluated in simulated knee arthroscopy. METHODS: 19 surgeons and 19 novices were randomized into either the control group (A) or intervention group (B) and tasked to perform 5 simulated loose-body retrieval procedures on a bench-top knee arthroscopy simulator. A cross-over study design was adopted whereby subjects alternated between devices during trials 1-3, deemed the "Unfamiliar" phase, and then used the same device consecutively in trials 4-5, to assess performance in a more "Familiarized" state. Measured outcomes were time-to-completion and incidence of bead drops. RESULTS: In the unfamiliar phase, HMD had 67% longer mean time-to-completion than TVM (194.7 ± 152.6s vs 116.7 ± 78.7s, P < .001). Once familiarized, HMD remained inferior to TVM, with 48% longer completion times (133.8 ± 123.3s vs 90.6 ± 55s, P = .052). Cox regression revealed device type (OR = 0.526, CI 0.391-0.709, P < .001) and number of procedure repetitions (OR = 1.186, CI 1.072-1.311, P = .001) are significantly and independently related to faster time-to-completion. However, experience is not a significant factor (OR = 1.301, CI 0.971-1.741, P = .078). Bead drops were similar between the groups in both unfamiliar (HMD: 27 vs TVM: 22, P = .65) and familiarized phases (HMD: 11 vs TVM: 17, P = .97). CONCLUSION: Arthroscopic procedures continue to be better performed under conventional TVM. However, similar quality levels can be reached by HMD when given more time. Given the theoretical advantages, further research into improving HMD designs is advocated.

Orthogeriatric Multidisciplinary Co-Management Across Acute and Rehabilitation Care Improves Length of Stay, Functional Outcomes and Complications in Geriatric Hip Fracture Patients.

Introduction: As the global number of geriatric hip fracture cases continues to proliferate, a newly developed orthogeriatric co-management multidisciplinary care model has been implemented since November 2018 to meet further increases in demand. Our objective was to evaluate the effectiveness of the new pathway in improving the clinical outcomes of fragility hip fractures. Methods: The data of geriatric hip fracture patients from 1 April 2018 till 30 October 2018 was collected as the conventional orthopaedic care model (pre-orthogeriatric care model) to compare with data from the orthogeriatric co-management model, 1 Feb 2019 till 31 August 2019. Clinical outcomes were analyzed between the groups, with the efficiency of the programme reflected in the total length of stay in acute and convalescent hospitals. Results: 194 patients were recruited to the conventional group and 207 were recruited to the orthogeriatric group, 290 patients (72.3%) were female. The mean (SD) patient age was 84.2 (7.9) years. The median length of stay in the acute and rehabilitation hospitals decreased by 1 day and 2 days, respectively (P=.001). The orthogeriatric group was associated with a higher Modified Barthel Index score on discharge from the rehabilitation hospital and more patients in the orthogeriatric collaboration group received osteoporosis medication prescription within one year after the index fracture. There was no difference in the 28-days unplanned readmission rate, complication rate, mortality rate or Elderly Mobility Scale scores on discharge from the rehabilitation hospital between the two groups. Conclusion: Orthogeriatric collaboration has been proven to be effective in terms of a decreased length of stay in both the acute and the rehabilitation hospitals.