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This study aimed to explore the potential of gait analysis coupled with supervised machine learning models as a predictive tool for assessing post-injury complications such as infection, malunion, or hardware irritation among individuals with lower extremity fractures. We prospectively identified participants with lower extremity fractures at a tertiary academic center. These participants underwent gait analysis with a chest-mounted inertial measurement unit device. Using customized software, the raw gait data were preprocessed, emphasizing 12 essential gait variables. The data were standardized, and several machine learning models, including XGBoost, logistic regression, support vector machine, LightGBM, and Random Forest, were trained, tested, and evaluated. Special attention was given to class imbalance, addressed using the synthetic minority oversampling technique (SMOTE). Additionally, we introduced a novel methodology to compute the post-injury recovery rate for gait variables, which operates independently of the time difference between the gait analyses of different participants. XGBoost was identified as the optimal model both before and after the application of SMOTE. Before using SMOTE, the model achieved an average test area under the ROC curve (AUC) of 0.90, with a 95% confidence interval (CI) of [0.79, 1.00], and an average test accuracy of 86%, with a 95% CI of [75%, 97%]. Through feature importance analysis, a pivotal role was attributed to the duration between the occurrence of the injury and the initial gait analysis. Data patterns over time revealed early aggressive physiological compensations, followed by stabilization phases, underscoring the importance of prompt gait analysis. χ 2 analysis indicated a statistically significant higher readmission rate among participants with underlying medical conditions (p = 0.04). Although the complication rate was also higher in this group, the association did not reach statistical significance (p = 0.06), suggesting a more pronounced impact of medical conditions on readmission rates rather than on complications. This study highlights the transformative potential of integrating advanced machine learning techniques like XGBoost with gait analysis for orthopedic care. The findings underscore a shift toward a data-informed, proactive approach in orthopedics, enhancing patient outcomes through early detection and intervention. The χ 2 analysis added crucial insights into the broader clinical implications, advocating for a comprehensive treatment strategy that accounts for the patient's overall health profile. The research paves the way for personalized, predictive medical care in orthopedics, emphasizing the importance of timely and tailored patient assessments., (© 2024 The Authors. Journal of Orthopaedic Research® published by Wiley Periodicals LLC on behalf of Orthopaedic Research Society.)

Background: Operative management of midfoot Charcot arthropathy often involves an extended midfoot arthrodesis with intramedullary bolts for fixation, a method called "beaming." Recently intramedullary nails have been introduced for the same indication, presumably providing stronger fixation. This study compares midfoot fusion nails to bolts with regard to stiffness and compressive ability. Additionally, we assessed how the addition of a subtalar fusion affects the construct., Methods: Medial column fusions were performed on 10 matched cadaver foot specimens with either a midfoot fusion nail or bolt. Specimens underwent cyclical compression loading, and displacement was measured. Separately, compressive forces produced were compared between the 2 fixation constructs using a synthetic bone block model. Lastly, another 10 matched specimens with midfoot fusion nails were evaluated with or without subtalar fusions., Results: No differences in stiffness were found in comparing matched specimens between nail vs bolt or comparing nail only without subtalar fusion (STF) vs nail with STF. The compressive force produced by the nail specimens was significantly and substantially greater than the bolted specimens (751.7 vs 139.0 N, P  = .01). The accumulated height drop at the midfoot after cycling was 0.5 mm more in the nail group than in the bolt group (1.72 vs 1.22 mm, P  = .008). The nail with STF group had greater initial height drop at the midfoot than the nail-only group (0.68 vs 0.34 mm, P  = .035) with similar initial height drop at the ankle. However, there were no differences in strength among the matched pairs of midfoot nail-only vs midfoot nail with STF as measured by displacement after fatigue or maximum force at load to failure., Conclusion: The overall cadaveric comparisons between matched pairs of nails vs bolts, and nail-only vs nail with STF, did not provide noteworthy differences between the groups with regard to strength or stiffness. However, the compressive force of the midfoot fusion nail was far superior to the bolt in a synthetic bone model. These data provide valuable insight comparing implants used in Charcot midfoot arthrodesis., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: The authors report receipt of equipment support from Wright Medical / Striker to perform this study. Carroll Jones, MD, reports royalties or licenses and consulting fees from Stryker and IBEX Charcot Solutions. Disclosure forms for all authors are available online.

Purpose: Instability of the proximal tibiofibular joint (PTFJ) can be treated with bicortical suspension (BCS) fixation. However, the ideal location, orientation, and configuration to apply one or two BCS devices are not clear., Methods: A finite-element model of the PTFJ was created from a female adult's CT dataset. Anterior and posterior ligaments at the PTFJ were modeled and suppressed to simulate stable and unstable joints. Fifty-six models simulated 56 device placements along guiding tunnel lines that connect eight entry locations on the fibular head to seven exit points on the anteromedial tibia. Doubling device stiffness created 56 more models. Combing any two placements created 1176 double-device configurations which were categorized to be crossed, divergent or parallel. Displacement of the fibular head relative to the fixed tibia under 100 N anterolateral and posteromedial forces was assessed., Results: Different placements had 2.1-27.9 mm translation with 0.7-8.9° internal rotation under anterolateral loading, and 1.8-5.2 mm translation with 6.1-7.9° external rotation under posteromedial loading. More transverse and superior orientations were associated with smaller anterolateral translation; more posterior and superior entry locations were associated with smaller internal rotation. The median (IQR) reductions in anterolateral translation by doubling device stiffness and by adding a second device were 0.8 (IQR 0.5-1.0) and 0.8 (IQR 0-6.1) mm, respectively. The type of double-device configurations had no significant effect on fibular motion., Conclusion: Surgeons should drill the guiding tunnel superiorly and transversely to ensure the optimal restoration of the PTFJ anterolateral stability., (© 2022. The Author(s) under exclusive licence to European Society of Sports Traumatology, Knee Surgery, Arthroscopy (ESSKA).)

Purpose: The ideal method of central slip reconstruction is difficult to determine due to the multitude of techniques, nonstandardized outcome reporting, and small patient series in the literature. Although most boutonniere deformities may be treated with nonsurgical measures, chronic, subacute, or open injuries may require operative intervention. To aid surgeons in the choice of the ideal central slip reconstruction method, this biomechanical study compared the 3 most common methods performed at our institution: direct repair, lateral band centralization, and distally-based flexor digitorum superficialis (FDS) slip repair., Methods: A boutonniere deformity was induced in 35 fresh-frozen cadaver digits. The central slip was repaired in 9 digits using a primary suture repair, in 9 digits using a lateral band centralization technique, and in 9 digits using a distally-based FDS slip reconstruction. A control group without injury was tested in 8 digits. Following repair or reconstruction, each digit was tested for load to failure, strain, and stiffness at the repair., Results: The average load to failure after central slip reconstruction was significantly greater for a distally based FDS slip method at 82.1 ± 14.6 N (95% CI, 62.2-101.9 N) than all other repair types. Although the FDS slip reconstruction was not as strong as the intact state (82.1 N vs 156.2 N, respectively), it was 2.6 times stronger than the lateral band centralization (82.1 N vs 31.6 N, respectively) and 3 times stronger than a primary repair (82.1 N vs 27.6 N, respectively)., Conclusions: Reconstruction of the central slip using a distally-based FDS slip provided the greatest biomechanical strength compared with the direct repair or lateral band centralization., Clinical Relevance: The use of a distally based reconstruction using FDS may allow for safer early motion., (Copyright © 2022 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.)

Background: Objective evaluation of patient outcomes has become an essential component of patient management. Along with patient-reported outcomes, performance-based measures (PBMs) such as gait analysis are an important part of this evaluation. The purpose of this study was to evaluate the validity of utilizing a wearable inertial measurement unit (IMU) in an outpatient clinic setting to assess its ability to provide clinically relevant data in patients with altered gait resulting from lower extremity trauma., Methods: Five orthopaedic trauma patients with varying degrees of gait pathologies were compared to 5 healthy control subjects. Kinematic data were simultaneously recorded by the IMU and a gold standard Vicon video motion analysis system (Vicon Motion Systems Ltd, Oxford, UK) during a modified 10-m walk test. Raw data captured by the IMU were directly compared to Vicon data. Additionally, 5 objective gait parameters were compared for controls and the 5 trauma patients., Results: The IMU data streams strongly correlated with Vicon data for measured variables used in the subsequent gait analysis: vertical acceleration, vertical displacement, pitch angular velocity, and roll angular velocity (Pearson r -value > 0.9 for all correlations). Quantitative kinematic data in post-trauma patients significantly differed from control data and correlated with observed gait pathology., Conclusions: When compared to the gold standard motion capture reference system (Vicon), an IMU can reliably and accurately measure clinically relevant gait parameters and differentiate between normal and pathologic gait patterns. This technology is easily integrated into clinical settings, requires minimal time, and represents a performance-based method for quantifiably assessing gait outcomes., Level of Evidence: Diagnostic Level 1 ., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2019 The Authors. Published by Wolters Kluwer Health, Inc. on behalf of the Orthopaedic Trauma Association.)

Objectives: Far cortical locking (FCL) constructs have been shown to increase axial interfragmentary displacement while limiting shear and have been specifically recommended in the treatment of distal femur fractures. However, there is no available data regarding their mechanical behavior within the range of bridge spans typically used for comminuted distal femur fractures. This biomechanical study of distal femur locked plate fixation assessed 4 methods of diaphyseal fixation for associated axial and shear displacement at bridge spans typically used in clinical practice., Methods: Distal femur locking plates were used to bridge simulated fractures in femur surrogates with 4 different methods of diaphyseal fixation (bicortical locking, bicortical nonlocking, near cortical locking, and FCL). Axial and shear displacement were assessed at 5 different bridge spans for each fixation method., Results: Diaphyseal fixation type was associated with the amount of shear (P = 0.04), but not the amount of axial displacement (P = 0.39). Specifically, FCL constructs demonstrated greater shear than bicortical locking (median 4.57 vs. 2.94 mm, P = 0.02) and bicortical nonlocking (median 4.57 vs. 3.41 mm, P = 0.02) constructs., Conclusions: Unexpectedly, FCL constructs demonstrated greater shear than bicortical locking and nonlocking constructs and similar axial displacement for all fixation methods. Bridge span had a dominant effect on displacement that interacted negatively with more flexible FCL diaphyseal fixation. Potentially interactive construct features are best studied in concert. Given the complexity of these relationships, computational modeling will likely play an integral role in future mechanotransduction research.

Purpose: To determine if the depth of anchor insertion affects the biomechanical performance of a 1.5-mm all-suture anchor in glenoid bone., Methods: A 1.5-mm all-suture anchor was tested in 8 matched pairs of human cadaver fresh-frozen glenoids. Anchors were inserted at 6 different locations and tested at 3 different depths: 21 mm (preset drilling depth), 17 mm, and 13 mm. Cyclic loading and destructive testing was performed. Displacement after 100 and 200 cycles, along with ultimate failure strength, was determined., Results: After 100 and 200 cycles, anchors placed at 13 and 17 mm had undergone significantly less displacement than those at 21 mm (P < .05). No difference was observed in ultimate load to failure between anchors placed at 21 and 17 mm. However, the ultimate load to failure was significantly lower in anchors placed at 13 mm (P < .05). There were 5 clinical failures in anchors placed at 21 mm, one at 17 mm, and none at 13 mm., Conclusions: The 1.5-mm all-suture anchor tested in this study has an optimal insertion depth of 17 mm, 4 mm shallower than the preset drill depth. At the optimal insertion depth of 17 mm, it underwent significantly less displacement after cyclic loading without a reduction in the ultimate load to failure., Clinical Relevance: Given the results of this study, the optimal insertion depth for this 1.5-mm all-suture anchor is 17 mm, 4 mm shallower than the preset drill depth., (Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)

Purpose: To quantify the distance of the dorsal ulnar sensory branch, floor of the extensor carpi ulnaris (ECU) subsheath, and ulnar neurovascular bundles from the triangular fibrocartilage complex (TFCC), and secondarily to assess the safety of an all-inside arthroscopic repair of the TFCC with a commonly used meniscal repair device with respect to the aforementioned structures., Methods: A custom K-wire with 1-mm gradation was used to determine the distance of at-risk structures from the periphery of the TFCC in 13 above-elbow human cadaver specimens. An all-inside repair of the TFCC at the location of a Palmer 1B tear was then performed using a commonly employed meniscal repair device. The distance from the deployed devices to the structure in closest proximity was then measured using digital calipers., Results: The mean distance from the deployed device to the nearest structure of concern for iatrogenic injury was 9.4 mm (range, 5-15 mm). The closest structure to iatrogenic injury was usually, but not always, the dorsal ulnar sensory nerve in 9 of 13 wrists (69.2%) at 9.3 mm (range, 5-15 mm); on 3 occasions it was instead the ulnar nerve (23.1%) at 9.5 mm (range, 9-10 mm), and on 1 occasion 6 mm from the flexor digitorum profundus to the little finger (7.7%). Forearm rotation had no significant effect on measured distances (ulnar nerve: P = .98; dorsal sensory: P = .89; ECU: P = .90). The largest influence of forearm rotation was a 0.4-mm difference between pronation and supination with respect to the distance of the TFCC periphery on the ECU subsheath., Conclusions: An all-inside arthroscopic TFCC repair using a commonly used meniscal repair device appears safe with respect to nearby neurovascular structures and tendons under typical arthroscopic conditions., Clinical Relevance: An all-inside arthroscopic TFCC repair using a commonly employed meniscal repair device appears safe in terms of proximity to important structures although further clinical investigation is warranted., (Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.)