Risk Of Stress Fracture Research Articles

Comparison of radiography and computed tomography for identification of third metacarpal structural change and associated assessment of condylar stress fracture risk in Thoroughbred racehorses.

Catastrophic injury has a low incidence but leads to the death of many Thoroughbred racehorses. To determine sensitivity, specificity, and reliability for third metacarpal condylar stress fracture risk assessment from digital radiographs (DR) and standing computed tomography (sCT). Controlled ex vivo experiment. A blinded set of metacarpophalangeal joint DR and sCT images were prepared from 31 Thoroughbreds. Four observers evaluated the condyles and parasagittal grooves (PSG) of the third metacarpal bone for the extent of dense bone and lucency/fissure and assigned a risk assessment grade for condylar stress fracture based on imaging features. Sensitivity and specificity for detection of subchondral structural changes in the condyles and PSG, and for risk assessment for condylar stress fracture were determined by comparison with a reference assessment based on sCT and joint surface examination. Agreement between observers and the reference assessment and reliability between observers were determined. Intra-observer repeatability was also assessed. Sensitivity for detection of structural change was lower than specificity for both imaging methods and all observers. For agreement with the reference assessment of structural change, correlation coefficients were generally below 0.5 for DR and 0.49-0.82 for sCT. For horses categorised as normal risk on reference assessment, observer assessment often agreed with the reference. Sensitivity for risk assessment was lower than specificity for all observers. For horses with a reference assessment of high risk of injury, observers generally underestimated risk. Diagnostic sensitivity of risk assessment was improved with sCT imaging, particularly for horses categorised as having elevated risk of injury from the reference assessment. Assessment repeatability and reliability was better with sCT than DR. The ex vivo study design influenced DR image sets. Risk assessment through screening with diagnostic imaging is a promising approach to improve injury prevention in racing Thoroughbreds. Knowledge of sensitivity and specificity of fetlock lesion detection provides the critical guidance needed to improve racehorse screening programs. We found improved detection of MC3 subchondral structural change and risk assessment for condylar stress fracture with sCT ex vivo.

Influence of Body Weight Measurement Frequency on the Bone Health of Female Athletes

ABSTRACT Purpose: Athletes struggle with bone stress injuries despite the many risk factors reported in previous studies. However, the relationship between body weight measurement frequency and risk of stress fractures has yet to be investigated. Thus, the purpose of this study is to seek the link between body weight measurement frequency and the occurrence of stress fractures. Method: This cross-sectional study included female athletes who were requested to fill out an anonymous online survey regarding their personal background, including the history of amenorrhea and stress fractures. In addition, the frequency at which they measured their body weight and composition and whether they had to report the same to their coaches and seniors were asked. Results: A total of 172 collegiate female athletes for 28 different types of sports participated in this study. Among the included athletes, 35.7% had a history of amenorrhea, whereas 29.7% had a history of stress fractures. A total of 57.0% of the athletes answered that in their team, they measure their body weight on a regular basis, and 33.1% of the athletes answered that they reported the data to their coaches. Logistic regression analysis revealed that those who measured their body weight at least once a day had a higher risk of sustaining stress fractures than did those who measured their body weight less than once a day (OR = 2.36, 95% CI 1.06–5.27, p = .04). Conclusion: Body weight measurement frequency was associated with the risk of stress fractures in female collegiate athletes.

ВЛИЯНИЕ ДЕФИЦИТА ВИТАМИНА Д НА ФИЗИЧЕСКУЮ ФОРМУ И РАБОТОСПОСОБНОСТЬ СПОРТСМЕНОВ

Purpose: Study of the effect of vitamin D deficiency on the physical fitness and performance of athletes, as well as providing up-to-date information on the diagnosis and treatment of this hypovitaminosis. Material and methods: The data of domestic and foreign literature on the effect of vitamin D deficiency on the physical form and performance of athletes were analyzed. The search was carried out using electronic databases MEDLINE, Embase, Scopus, Web of Science, eLIBRARY for the period from 2007 to 2022. For the search, we used keywords and their combinations: “athletes”, “physical performance”, “stress fracture “, “vitamin D”. A total of 33 sources were analyzed. Results: Vitamin D plays an important role in the human body. With its deficiency in athletes, there is an increase in the risk of injury, a decrease in the functional abilities of muscles and an increase in the risk of stress fractures of bones. A prolonged and pronounced deficiency of this vitamin in athletes leads to a deterioration in general well-being, a disruption in the functioning of almost all body systems, a decrease in the level of working capacity and sports performance. The fundamental method of treatment and prevention of vitamin D deficiency in athletes is the correction of lifestyle, training schedule and the use of specialized supplements containing cholecalciferol. Discussion: The required amount of cholecalciferol intake varies from 400 to 2000 IU / day, depending on many factors, including the amount of sun exposure during the day, age, gender, severity of deficiency, ethnicity, etc. Athletes also need to consume sufficient amounts of micro- and macronutrients, especially calcium and magnesium. When taking cholecalciferol, one should take into account the possibility of intoxication, which occurs due to the consumption of excessive amounts of supplements of this vitamin. Conclusions: At the moment, due to the widespread prevalence of vitamin D deficiency in athletes and its negative impact on the health and performance of an athlete, there is a need for more active measures aimed at the timely diagnosis of this hypovitaminosis and its treatment.

Effects of a 10-week footstrike transition programme on tibial stress fracture probability; a randomized controlled intervention using finite element and probabilistic modelling

Introduction: The aim of this study was to undertake a randomized control trial examining the effects of a 10-week footstrike transition program on tibial stress fracture risk compared to control. Material and methods: Twenty habitual rearfoot strike runners were randomly assigned to either footstrike or control groups. The footstrike group undertook a graduated 10-week program which allowed them to convert their habitual rearfoot strike pattern, whereas the control group maintained their normal training regime without any alterations to their strike pattern. Running biomechanics were collected using an eight-camera motion capture system, and ground reaction forces using a force plate. Tibial strains were quantified using finite element modelling and stress fracture probability calculated via probabilistic modelling over 100 days of running. The primary outcome: tibial stress fracture probability, and secondary outcomes: running biomechanics, muscle forces, joint contact forces, and tibial strain indices were measured at baseline and after 10 weeks. Results: Intention-to-treat analyses revealed no significant alterations in the primary outcome (Footstrike: baseline = 12.82% & 10-weeks = 10.82%, Control: baseline = 15.43% & 10-weeks = 13.39%) between arms. However, alterations in the strike index (Footstrike: baseline = 21.79% & 10-weeks = 65.74%, Control: baseline = 13.61% & 10-weeks = 12.41%) and the loading rate (Footstrike: baseline = 165.85BW/s & 10-weeks = 100.01 BW/s, Control: baseline = 170.13 BW/s & 10-weeks = 197.87 BW/s) were significantly greater in the footstrike group compared to the control one. Conclusion: This trial concludes that the footstrike intervention adopted in this study was not effective in mediating improvements in tibial stress fracture risk, although future intervention trials could examine the efficacy of footstrike modification on other musculoskeletal injuries in runners.

Implant-Positioning and Patient Factors Associated with Acromial and Scapular Spine Fractures After Reverse Shoulder Arthroplasty

Background: This study aimed to identify implant positioning parameters and patient factors contributing to acromial stress fractures (ASFs) and scapular spine stress fractures (SSFs) following reverse shoulder arthroplasty (RSA). Methods: In a multicenter retrospective study, the cases of patients who underwent RSA from June 2013 to May 2019 and had a minimum 3-month follow-up were reviewed. The study involved 24 surgeons, from 15 U.S. institutions, who were members of the American Shoulder and Elbow Surgeons (ASES). Study parameters were defined through the Delphi method, requiring 75% agreement among surgeons for consensus. Multivariable logistic regression identified factors linked to ASFs and SSFs. Radiographic data, including the lateralization shoulder angle (LSA), distalization shoulder angle (DSA), and lateral humeral offset (LHO), were collected in a 2:1 control-to-fracture ratio and analyzed to evaluate their association with ASFs/SSFs. Results: Among 6,320 patients, the overall stress fracture rate was 3.8% (180 ASFs [2.8%] and 59 SSFs [0.9%]). ASF risk factors included inflammatory arthritis (odds ratio [OR] = 2.29, p < 0.001), a massive rotator cuff tear (OR = 2.05, p = 0.010), osteoporosis (OR = 2.00, p < 0.001), prior shoulder surgery (OR = 1.82, p < 0.001), cuff tear arthropathy (OR = 1.76, p = 0.002), female sex (OR = 1.74, p = 0.003), older age (OR = 1.02, p = 0.018), and greater total glenoid lateral offset (OR = 1.06, p = 0.025). Revision surgery (versus primary surgery) was associated with a reduced ASF risk (OR = 0.38, p = 0.019). SSF risk factors included female sex (OR = 2.45, p = 0.009), rotator cuff disease (OR = 2.36, p = 0.003), osteoporosis (OR = 2.18, p = 0.009), and inflammatory arthritis (OR = 2.04, p = 0.024). Radiographic analysis of propensity score-matched patients showed that a greater increase in the LSA (ΔLSA) from preoperatively to postoperatively (OR = 1.42, p = 0.005) and a greater postoperative LSA (OR = 1.76, p = 0.009) increased stress fracture risk, while increased LHO (OR = 0.74, p = 0.031) reduced it. Distalization (ΔDSA and postoperative DSA) showed no significant association with stress fracture prevalence. Conclusions: Patient factors associated with poor bone density and rotator cuff deficiency appear to be the strongest predictors of ASFs and SSFs after RSA. Final implant positioning, to a lesser degree, may also affect ASF and SSF prevalence in at-risk patients, as increased humeral lateralization was found to be associated with lower fracture rates whereas excessive glenoid-sided and global lateralization were associated with higher fracture rates. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Biomechanical role of bone grafting for calcaneal fracture fixation in the presence of bone defect: A finite element analysis

BackgroundThe purpose of this study was to compare the biomechanical stress and stability of calcaneal fixations with and without bone defect, before and after bone grafting, through a computational approach. MethodsA finite element model of foot-ankle complex was reconstructed, impoverished with a Sanders III calcaneal fracture without bone defect and with moderate and severe bone defects. Plate fixations with and without bone grafting were introduced with walking stance simulated. The stress and fragment displacement of the calcaneus were evaluated. FindingsModerate and severe defect increased the calcaneus stress by 16.11% and 32.51%, respectively and subsequently decreased by 10.76% and 20.78% after bone grafting. The total displacement was increased by 3.99% and 24.26%, respectively by moderate and severe defect, while that of posterior joint facet displacement was 86.66% and 104.44%. The former was decreased by 25.73% and 35.96% after grafting, while that of the latter was reduced by 88.09% and 84.78% for moderate and severe defect, respectively. InterpretationOur finite element prediction supported that bone grafting for fixation could enhance the stability and reduce the risk of secondary stress fracture in cases of bone defect in calcaneal fracture.

Subchondral bone fatigue injury in the parasagittal condylar grooves of the third metacarpal bone in thoroughbred racehorses elevates site-specific strain concentration

Condylar stress fracture of the distal end of the third metacarpal/metatarsal (MC3/MT3) bones is a major cause of Thoroughbred racehorse injury and euthanasia worldwide. Functional adaptation to exercise and fatigue damage lead to structural changes in the subchondral bone that include increased modeling (resulting in sclerotic bone tissue) and targeted remodeling repair (resulting in focal resorption spaces in the parasagittal groove). Whether these focal structural changes, as detectable by standing computed tomography (sCT), lead to elevated strain at the common site of condylar stress fracture has not been demonstrated. Therefore, the goal of the present study was to compare full-field three-dimensional (3D) strain on the distopalmar aspect of MC3 bone specimens with and without focal subchondral bone injury (SBI). Thirteen forelimb specimens were collected from racing Thoroughbreds for mechanical testing ex vivo and underwent sCT. Subsequently, full-field displacement and strain at the joint surface were determined using stereo digital image correlation. Strain concentration was observed in the parasagittal groove (PSG) of the loaded condyles, and those with SBI in the PSG showed higher strain rates in this region than control bones. PSG strain rate in condyles with PSG SBI was more sensitive to CT density distribution in comparison with condyles with no sCT-detectable injury. Findings from this study help to interpret structural changes in the subchondral bone due to fatigue damage and to assess risk of incipient stress fracture in a patient-specific manner.

Stress fractures and overuse injuries in children and adolescents

There is an intricate connection between physical activity, bone health, and the susceptibility to stress fractures and overuse injuries. Physical activity has a positive impact on bone strength while a sedentary lifestyle can lead to a heightened risk for injury. The rise of early sports specialization has led to a substantial increase in overuse injuries, particularly in individual sports.Bone Stress Injuries (BSI) represent a category of overuse injuries closely linked to single sport specialization. BSI involves a spectrum of altered bone mechanics, ranging from edema of periosteum, endosteum, and bone; potentially leading to partial or full cortical breaks. This condition is prevalent in high-level athletes and encompasses stress reactions and fractures, resulting from an imbalance between injury creation and repair. Up to 20% of adolescents are affected, with the tibia being the most common location, predominantly occurring in athletes aged 15 to 25. A holistic approach integrating both physical and nutritional aspects is warranted to ensure sustained musculoskeletal health across diverse pediatric and adolescent groups and athletic endeavors. Key Concepts(1)Early and single sports specialization has a substantial impact on overuse injuries.(2)Bone stress injuries are common in high-level athletes resulting from an imbalance between creation and repair of injury.(3)Relative energy deficiency in sports (REDS) is related to a higher risk for recurrent Bone Stress Injuries.(4)Athletes that are lacking vitamin D are found to have an increased risk for stress fractures.

The Influence of Component Design and Positioning on Soft-Tissue Tensioning and Complications in Reverse Total Shoulder Arthroplasty: A Review.

» Reverse total shoulder arthroplasty was designed to function in the rotator cuff deficient shoulder by adjusting the glenohumeral center of rotation (COR) to maximize deltoid function.» Adjustments in the COR ultimately lead to changes in resting tension of the deltoid and remaining rotator cuff, which can affect implant stability and risk of stress fracture.» Soft-tissue balance and complication profiles can be affected by humeral component (version, neck shaft angle, and inlay vs. onlay) and glenoid component (sagittal placement, version, inclination, and lateralization) design and application.» A good understanding of the effects on soft-tissue balance and complication profile is critical for surgeons to best provide optimal patient outcomes.

Robert H. Cofield, MD, Award for Best Oral Presentation 2023: Up to 8 mm of glenoid-sided lateralization does not increase the risk of acromial or scapular spine stress fracture following reverse shoulder arthroplasty with a 135° inlay humeral component

BackgroundGlenoid-sided lateralization in reverse shoulder arthroplasty (RSA) decreases bony impingement and improves rotational range of motion, but has been theorized to increase the risk of acromial or scapular spine fractures (ASF). The purpose of this study was to assess the if glenoid-sided lateralization even up to 8 mm increases risk for stress fracture following RSA with a 135° inlay humeral component. MethodsA retrospective review was performed from a multicenter prospectively collected database on patients who underwent primary RSA from 2015-2021. All RSAs were performed with a 135° inlay humeral component. Varying amounts of glenoid lateralization were used from 0 to 8 mm. Preoperative radiographs were reviewed for the presence of acromial thinning, acromiohumeral distance (AHD), and inclination. Postoperative implant position (distalization, lateralization, and inclination) as well as the presence of ASF were evaluated on minimum 1-year postoperative radiographs. Regression analyses was performed on component and clinical variables to assess for factors predictive of ASF. ResultsAcromial or scapular spine fractures were identified in 26 out of 470 shoulders (5.5%). Glenoid-sided lateralization was not associated with ASF risk (p = 0.890). Furthermore, the incidence of fracture did not vary based on glenoid-sided lateralization (0-2mm - 7.4%, 4mm - 5.6%, 6mm - 4.4%, 8mm - 6.0%; p > .05 for all comparisons). RSA on the dominant extremity was predictive of fracture (OR 2.21, 95% CI 1.20-5.75 p = 0.037), but there was no relationship between patient age, sex, preoperative acromial thinning, or diagnosis and risk of fracture. While there was no difference in mean postoperative AHD between groups (p = .443), the pre- to postoperative delta AHD was higher in the stress fracture group (2.0 ± 0.7 cm vs. 1.7 ± 0.7 cm; p = 0.015). For every centimeter increase in delta AHD, there was a 121% increased risk for fracture (OR 2.21, 95% CI 1.33-3.68; p = 0.012) Additionally, for 1 mm increase in inferior glenosphere overhang, there was a 19% increase in fracture risk (p = 0.025). ConclusionUp to 8 mm of glenoid-sided metallic lateralization does not appear to increase the risk of ASF when combined with a 135° inlay humeral implant. Humeral distalization increases the risk of ASF, particularly when there is a larger change between pre- and postoperative AHD or higher inferior glenosphere overhang. In cases of pronounced preoperative superior humeral migration, it may be a consideration to avoid excessive postoperative distalization, but minimizing bony impingement via glenoid-sided lateralization appears to be safe.

The Impact of Running Experience and Shoe Longitudinal Bending Stiffness on Lower Extremity Biomechanics

Purpose The impacts of shoe stiffness on running biomechanics are well-documented, while the specific effects on the performance of biomechanically distinct groups such as novice runners and experienced runners are still largely unexplored. The study aimed to evaluate the biomechanical effects of different shoe longitudinal bending stiffness (adjusted by inserting carbon plate) on the lower limb during running in novice runners and experienced runners. Methods Twelve experienced runners and ten novice runners ran at a speed of 4.47 m/s while randomly wearing shoes with either low stiffness (5.9 Nm/rad) or high stiffness (8.6 Nm/rad). An Opensim musculoskeletal model was adopted for estimating lower limb joint angles, joint angular velocities, joint moment, joint work, peak joint reaction forces during running stance phase. Results Results showed that novice runners displayed greater lower limb joint mobility and less joint moment, while experienced runners exhibited less joint mobility but greater joint moment, and higher peak joint reaction forces were observed at the knee and ankle joints. Furthermore, increased shoe longitudinal bending stiffness resulted in higher peak joint reaction forces at the metatarsophalangeal joint for novice runners while lower for experienced runners. Conclusions Novice runners may face an increased risk of metatarsal pain or stress fractures when dealing with higher shoe stiffness. This nuanced understanding of joint dynamics underscores the need for tailored training and footwear recommendations to mitigate injury risks specific to different levels of running experience.

Risk factors of metatarsal stress fracture associated with repetitive sports activities: a systematic review.

Metatarsal stress fracture is common in people engaged in repetitive weight-bearing activities, especially athletes and recruits. Identifying risk factors in these contexts is crucial for effective prevention. A systematic search on Web of Science, PubMed, EBSCO, SPORTDiscus, MEDLINE, and Cochrane Library was conducted and the date range for the retrieval was set from January 1984 to April 2024. 32 eligible studies were selected from 1,728 related research. Anatomical and biomechanical factors, such as higher foot arch, abnormal inversion/eversion of foot, and longer metatarsal length or larger angles, relatively influence stress fracture risk. However, given that there is no standardized measurement, the results remain to be examined. Soccer is associated with fifth metatarsal fractures, while long-distance running and recruit training often lead to fractures of the second or third metatarsals. High exercise intensity, non-adaptive training, and inadequate equipment heighten fracture risk. This review highlights the complex interplay of anatomical, biomechanical, and sports-related factors in the risk of metatarsal stress fractures. Relatively, high arches, specific metatarsal morphologies, and foot inversion/eversion patterns are significant risk factors, particularly among athletes. Sports type also correlates with metatarsal stress fracture locations. Despite extensive research, study heterogeneity and inherent biases necessitate cautious interpretation. Comprehensive, multifactorial approaches and personalized injury prevention strategies are essential for reducing the incidence of these injuries and improving the health and performance of athletes.

Comparative evaluation of stress distribution against the root canal wall at three different levels using novel NiTi rotary files - A finite element analysis.

Recent innovations in the physical and mechanical features of endodontic file systems have diminished the prospect of stress generation and fracture risk in novel endodontic files. The purpose of this research was to comparatively evaluate the stress distribution of recently introduced endodontic rotary files with distinct features and metallurgy at three different levels of the root canal wall by finite element analysis. Forty endodontic files were used in this experiment after being inspected through a scanning electron microscope for any surface deformities. Based on their metallurgy and design, the scanned files were divided into four groups, each with 10 samples: Group A-2Shape files, Group B-F360, Group C-One Curve, and Group D-TruNatomy. To assess the mechanical behavior of these files, the stress produced by computer-aided models of these instruments on the dentinal wall of a simulated root canal was numerically analyzed using ANSYS® 15 Workbench finite element software. A one-way ANOVA was used to assess all the raw data with post hoc Tukey analysis, the Shapiro-Wilk test, and Levene's test. F360 files exerted the maximum stress on the dentinal wall, while TruNatomy files exerted the least stress at all the distinct levels of dentinal walls. There was no statistically significant variation in the stress generated between the four groups. Therefore, it can be concluded that improvements in rotary file design and metallurgy have the potential to reduce the stress during canal shaping and the risk of instrument breakage during clinical use.

Regular Nonsteroidal Anti-Inflammatory Drug Use Increases Stress Fracture Risk in the General Population: A Retrospective Case-Control Study.

Previous studies have shown that the use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with increased stress fracture risk. This phenomenon has been studied predominantly in high-activity individuals, so data regarding the general population are limited despite the substantial economic and resource burden of stress fracture injuries within the general US population. Furthermore, our preclinical studies demonstrate that regular use of NSAIDs also diminishes the intrinsic ability of bone to resist fracture. To determine the association of regular NSAID use with stress fractures in the general population, we surveyed subjects presenting with either stress fracture or uncomplicated ankle sprain to assess their use of NSAIDs over the three months before their injury. We hypothesized that subjects with stress fractures would have increased regular NSAID usage as compared to controls. Subjects diagnosed with a stress fracture (n = 56) and subjects with uncomplicated ankle sprains (n = 51; control) were surveyed about their NSAID use at the time of their diagnosis and in the previous three months using a questionnaire based on the National Health and Nutrition Examination Survey (NHANES). Subjects were surveyed in person on the day of their injury diagnosis or by phone within 30 days of their diagnosis. Fisher's exact test was used to determine significant differences in NSAID usage between stress fracture and control subjects. Subjects diagnosed with stress fractures had a statistically significant increase in both current use (p=0.03) and regular use (p=0.04) of ibuprofen/naproxen/celecoxib as compared to control subjects. There were no significant differences in the use of aspirin, acetaminophen, or prescription medications containing acetaminophen between groups. Consistent with previous clinical reports, we observed a strong correlation between regular ibuprofen/naproxen/celecoxib use and stress fracture incidence in the general population. These results indicate that patients at high risk of stress fracture should avoid regular use of ibuprofen, naproxen, or celecoxib.

Concomitant open distal clavicle excision is associated with greater improvement in range of motion without increased risk of acromial stress fracture after reverse total shoulder arthroplasty: a retrospective cohort study.

The purpose of this study was to evaluate the effect of concomitant open distal clavicle excision (DCE) on postoperative clinical outcomes and incidence of acromial and scapular stress fractures (ASFs) in patients with symptomatic acromioclavicular joint osteoarthritis (ACJ OA) undergoing reverse total shoulder arthroplasty (RTSA). A single-surgeon retrospective cohort study was conducted including patients who underwent primary elective RTSA with or without DCE from 2015 to 2019 with a minimum 6-month follow-up period. Shoulder active range of motion (AROM) and visual analog scale (VAS) pain were recorded preoperatively and postoperatively. ASFs and other adverse events were identified using postoperative notes and/or radiographs. Characteristics and outcomes were compared between the RTSA and RTSA-DCE groups. Forty-six RTSA patients (mean age, 67.9±8.7 years; 60.9% male; mean follow-up, 24.9±16.6 months) and 70 RTSA-DCE patients (mean age, 70.2±8.9 years; 20.0% male; mean follow-up, 22.7±12.9 months) were included. There were no significant intergroup differences in rates of ASF (RTSA, 0.0% vs. RTSA-DCE, 1.4%; P=1.00), stress reactions (RTSA, 8.7% vs. RTSA-DCE, 11.4%; P=0.76), reoperation, revision, or infection (all P>0.05), or in pre-to-postoperative reduction in VAS pain (P=0.17) at latest follow-up. However, the RTSA-DCE group had greater pre-to-postoperative improvement in flexion AROM (RTSA, 43.7°±38.5° vs. RTSA-DCE, 59.5°±33.4°; P=0.03) and internal rotation (IR) AROM (P=0.02) at latest follow-up. Concomitant DCE in RTSA improves shoulder flexion and IR AROM, alleviates shoulder pain, and does not increase the risk of ASFs. Level of evidence: III.

Postoperative Medial Malleolar Fractures in Total Ankle Replacement are Associated with Medial Malleolar Width and Coronal Alignment

Category: Ankle Arthritis; Ankle Introduction/Purpose: There is limited evidence regarding risk factors for medial malleolar fractures after total ankle arthroplasty (TAA). A previous study showed that patients with medial pain following TAA had significantly thinner (<11mm) medial malleolar width, which has been used as a threshold for placing a prophylactic screw. However, this study included only six patients with pain over the medial malleolus. Other previously reported risk factors include coronal malalignment and poor bone quality. Therefore, this study examined the risk factors of postoperative medial malleolar stress fractures. In addition, we sought to assess the effect of the prophylactic screw placement. We hypothesized that a medial malleolar width <11mm and varus malalignment would be associated with increased fracture risk and that the prophylactic screw placement would be protective. Methods: A case-control study was conducted on 838 patients undergoing primary TAA between 2015 and. TAA revisions, arthrodesis takedowns, and intraoperative medial malleolar fractures were excluded. Demographic and surgical data were obtained. A total of 21 patients with postoperative medial malleolar stress fractures > 4 weeks postoperatively (cases) were identified through radiologic assessment (radiograph, CT, or MRI) and matched to a control group of 129 patients. Radiographic evaluation included pre- and post-TAA tibial coronal alignment, postoperative medial malleolar width at the tibial component, and prophylactic screw fixation. Demographics and radiographic variables were compared between cohorts using the Mann-Whitney U test for continuous variables and Pearson Chi-square for categorical variables. Logistic regression was used to investigate the association of medial malleolar stress fractures with gender, coronal tibial implant size, postoperative coronal alignment, prophylactic screw fixation, and medial malleolar width using odds ratios (OR), and standard error (SE). Results: Of 838 TAAs, 2.51% sustained a postoperative medial malleolar fracture (n = 21). Of these, 13/21 (61.9%) required reoperation: internal fixation (12) and TAA revision (1). Mean (SD) medial malleolar width was significantly smaller in the fracture cohort (8.62 mm [1.63]) than in controls (11.78mm [1.75]), P<0.001). Mean (SD) postoperative tibial component coronal alignment was 92.2º (2.82) for patients with medial malleolar fracture and 90.23º (1.68) for the control cohort (P = 0.003). Postoperative varus tibial component alignment (OR = 1.61 [95%CI 1.16 02 − 2.22], P = 0.004) and smaller medial malleolar width (OR = 0.11 [95% CI 0.04 02 − 0.3], P < 0.001) were associated with increased probability of a post-TAA medial malleolar fracture. Prophylactic screw fixation resulted in a 90% reduction in the odds of a fracture (OR = 0.10 [95%CI 0.02 02 − 0.64], P = 0.015). A medial malleolar width of 10.31 mm was identified as a threshold for predicting a medial malleolar stress fracture. Conclusion: In this study, the prevalence of postoperative periprosthetic fractures after TAA was similar to prior studies. Decreased medial malleolar thickness and postoperative varus malalignment were associated with an increased risk of a postoperative medial malleolar stress fracture. A malleolar width of 10.31 mm was identified as a potential threshold. Prophylactic medial malleolar screw fixation was protective and associated with a 90% reduction in fracture probability. Surgeons should consider prophylactic screw fixation patients with a medial malleolar width < 10.31 mm or at risk of postoperative varus deformity.

Effects of Stature and Load Carriage on the Running Biomechanics of Healthy Men.

Overuse musculoskeletal injuries, often precipitated by walking or running with heavy loads, are the leading cause of lost-duty days or discharge during basic combat training (BCT) in the U.S. military. The present study investigates the impact of stature and load carriage on the running biomechanics of men during BCT. We collected computed tomography images and motion-capture data for 21 young, healthy men of short, medium, and tall stature (n = 7 in each group) running with no load, an 11.3-kg load, and a 22.7-kg load. We then developed individualized musculoskeletal finite-element models to determine the running biomechanics for each participant under each condition, and used a probabilistic model to estimate the risk of tibial stress fracture during a 10-week BCT regimen. Under all load conditions, we found that the running biomechanics were not significantly different among the three stature groups. However, compared to no load, a 22.7-kg load significantly decreased the stride length, while significantly increasing the joint forces and moments at the lower extremities, as well as the tibial strain and stress-fracture risk. Load carriage but not stature significantly affected the running biomechanics of healthy men. We expect that the quantitative analysis reported here may help guide training regimens and reduce the risk of stress fracture.

Effect of stride length on the running biomechanics of healthy women of different statures.

Tibial stress fracture is a debilitating musculoskeletal injury that diminishes the physical performance of individuals who engage in high-volume running, including Service members during basic combat training (BCT) and recreational athletes. While several studies have shown that reducing stride length decreases musculoskeletal loads and the potential risk of tibial injury, we do not know whether stride-length reduction affects individuals of varying stature differently. We investigated the effects of reducing the running stride length on the biomechanics of the lower extremity of young, healthy women of different statures. Using individualized musculoskeletal and finite-element models of women of short (N = 6), medium (N = 7), and tall (N = 7) statures, we computed the joint kinematics and kinetics at the lower extremity and tibial strain for each participant as they ran on a treadmill at 3.0m/s with their preferred stride length and with a stride length reduced by 10%. Using a probabilistic model, we estimated the stress-fracture risk for running regimens representative of U.S. Army Soldiers during BCT and recreational athletes training for a marathon. When study participants reduced their stride length by 10%, the joint kinetics, kinematics, tibial strain, and stress-fracture risk were not significantly different among the three stature groups. Compared to the preferred stride length, a 10% reduction in stride length significantly decreased peak hip (p = 0.002) and knee (p < 0.001) flexion angles during the stance phase. In addition, it significantly decreased the peak hip adduction (p = 0.013), hip internal rotation (p = 0.004), knee extension (p = 0.012), and ankle plantar flexion (p = 0.026) moments, as well as the hip, knee, and ankle joint reaction forces (p < 0.001) and tibial strain (p < 0.001). Finally, for the simulated regimens, reducing the stride length decreased the relative risk of stress fracture by as much as 96%. Our results show that reducing stride length by 10% decreases musculoskeletal loads, tibial strain, and stress-fracture risk, regardless of stature. We also observed large between-subject variability, which supports the development of individualized training strategies to decrease the incidence of stress fracture.

Relationship Between Calcium and Vitamin D Level and Bone Stress Fracture in Young Athletes

Objective: To determine the association of vitamin D and serum calcium with stress fractures in young athletes. Methods: In this prospective case-control study, we included 160 young athletes who presented to the department of orthopedics, CMH Abbottabad from June-2022 to January-2023. Among those there were 80 patients who presented with stress fractures and 80 patients were those who presented with lower extremity fractures other than stress fractures. Serum calcium and vit. D levels were determined in all patients. Results: Mean age in patients with stress fractures (cases) was 20.3±6.1 years while those in control group was 21.7±8.4 years (p-value 0.22). Mean vit. D levels were significantly lower in cases group; 24.64±11.2 ng/mL versus 30.2±14.7 ng/mL in control group (p-value 0.007). Mean serum PTH levels were no statistically significantly different between the groups; 3.2±1.3 pmol/L versus 3.4±1.7 pmol/L in cases and control group respectively, p-value 0.40. Serum calcium levels in cases were lower; 1.9±0.8 mmol/L in comparison to control group; 2.1±0.7 mmol/L, with p-value 0.01. Conclusion: There is a significant association of serum calcium and vitamin D levels with stress fractures. So regular intake of vitamin D containing foods and milk products should be advised to young athletes to reduce the risk of stress fractures. Keywords: Stress fractures, Athletes, calcium, Vitamin D.

A continuum damage model of fatigue and failure in whole bone

Predicting the fatigue failure of whole bone may provide insight into the etiology of stress fractures and lead to new methods for preventing and rehabilitating these injuries. Although finite element (FE) models of whole bone have been used to predict fatigue failure, they often do not consider the cumulative and nonlinear effect of fatigue damage, which causes stress redistribution over many loading cycles. The purpose of this study was to develop and validate a continuum damage mechanics FE model for the prediction of fatigue damage and failure. Sixteen whole rabbit-tibiae were imaged using computed tomography (CT) and then cyclically loaded in uniaxial compression until failure. CT images were used to generate specimen-specific FE models and a custom program was developed to iteratively simulate cyclic loading and progressive modulus degradation associated with mechanical fatigue. Four tibiae from the experimental tests were used to develop a suitable damage model and define a failure criterion; the remaining twelve tibiae were used to test the validity of the continuum damage mechanics model. Fatigue-life predictions explained 71% of the variation in experimental fatigue-life measurements with a directional bias towards over-predicting fatigue-life in the low-cycle regime. These findings demonstrate the efficacy of using FE modeling with continuum damage mechanics to predict damage evolution and fatigue failure of whole bone. Through further refinement and validation, this model may be used to investigate different mechanical factors that influence the risk of stress fractures in humans.