21 research outputs found
Lagrangian Approach to Modeling the Biodynamics of the Upper Extremity: Applications to Collegiate Baseball Pitching
No full textBiomechanical modeling can provide information regarding movement patterns and allow for an improved understanding of injury mechanisms. Biomechanical models typically rely on Newtonian mechanics leading to computationally intensive models; however, an often overlooked means of solving these same modeling needs is to apply the Lagrangian approach. This approach allows for a more direct means of solving the equations of motion; leading to more accurate models of human motion. The purpose of this project was to create a Lagrangian based model of the upper extremity to describe joint kinematics and kinetics as well as muscle kinetics during complex motion tasks.
The model developed in this work was a four segment, 18 degree of freedom model capable of providing joint moments as well as muscle force estimates. The model was then applied to data collected from 33 collegiate level baseball pitchers. The results of this project indicated that the model was capable of accurately predicting the motion profiles of the upper extremity joints. The results also indicated that the model was able to accurately estimate muscle forces leading to a greater understanding of pitching related injuries. The adaptability of the model offers the ability to create patient specific treatment plans or modify a pitcher’s mechanics to decreased joint moments. Finally, the results of this work illustrate the utility of using Lagrangian based biomechanics models to create accurate and adaptable models to describe complex human movement
The Use of Motion Analysis Technology as an Alternative Means of Assessing Spinal Deformity in Patients with Adolescent Idiopathic Scoliosis
No full textAdolescent Idiopathic Scoliosis (AIS) is a three dimensional deformity of the spine that causes abnormal curvatures in the coronal and sagittal planes and abnormal vertebral rotations. The gold standard for diagnosing and tracking the progression of the deformity is through the use of repeated radiography and a patient can receive upwards of fifteen radiographic series over the course of treatment, which exposes this population to an increased risk of radiation-dependent complications.
This thesis presents the necessary calculations and the marker set required to make the motion capture technology a viable alternative to radiographs, in an effort to reduce the patient’s exposure to ionizing radiation. Using retro-reflective markers and force plates, it is possible to determine asymmetries in the frontal and transverse plane, to calculate the balance of the spine, to replicate common radiographic measures, and to determine the kinematic profiles of the spine for each patient.
The results of this work successfully showed that there is a high correlation between the radiographic measures and those calculated using motion analysis technology. When applied clinically, the results from a small set of AIS patients indicated that the motion analysis technology can help describe the underlying spinal and muscular deformities of patients with AIS. This work provides a viable means of reducing the number of radiographs this patient population is subjected to over the course of their non-operative treatment. It also provides a strong foundation for future work on applying motion capture technology to advance scoliosis research
The oswestry disability index in elective single level lumbar fusion: Is 3 months follow up enough?
No full textABSTRACT: Background: Prospective, longitudinal collection of patients reported outcomes (PRO) has become an essential metric in orthopedics. Despite the utility of PROs, data collection presents a significant challenge to the healthcare system. There is a need to better understand if serial data collection over a 1 to 2 year postoperative period is truly warranted. The purpose of this study was to determine if continued PRO collection after 3 months postop is needed in patients that underwent lumbar fusion. Methods: This retrospective study utilized 239 patients that underwent an elective single level lumbar fusion between April 1, 2020 and February 1, 2023. Changes in the Oswestry Disability Index (ODI) scores over a 1 year period were assessed for all patients. Patients were placed into 1 of 3 study groups, those that improved by 10 points, those that worsened by 10 points, and those that did not change (score change less than 10 points in either direction). Movement between study groups, the minimal clinical important difference (MCID), and patient satisfaction were analyzed for each patient. Results: Improvement between preoperative and the 3 month postoperative evaluations was noted for most patients. There was limited change in scores after 3 months. Patients in the improved group continued to improve through 1 year postoperative. Patients in the worsened group continued to decline by 1 year postoperative. Patients in the no change group demonstrated the highest potential to change groups. Conclusions: Patients with substantial improvement or worsening at 3 months have a low likelihood of substantial clinical change thereafter. This subset of patients may not need further evaluation with PROs, but those in the worsened group may benefit from other interventions to potentially alter their course
Impact of Pediatric Subspecialty Training on Perioperative Complications in Adolescent Idiopathic Scoliosis Surgery
No full textStreamlining Postoperative Care After Pediatric Supracondylar Humerus Fractures: Is Follow-up After Pin Removal Routinely Needed?
No full textLong-term outcomes of external femoral derotation osteotomies in children with cerebral palsy
No full textForearm Rotation Moments are Associated with Elbow Varus Moments
No full textObjectives: The incidence of upper extremity injury in baseball has increased over the past decade, and much of the research into the biomechanics of pitching has focused on the shoulder and elbow. However little attention has been placed on how forearm rotation and the forearm rotation moment could affect a pitcher’s risk of injury. Therefore this study sought to determine the association between forearm moments and the elbow varus moment in collegiate baseball pitchers. Methods: Collegiate level baseball pitchers that were recruited for this study were actively pitching for an NCAA team and had no history of surgery to their pitching arms. All pitchers underwent a pitching analysis using computerized motion analysis techniques. The forearm’s position, rotational velocity, and supination and pronation moments were analyzed using a random intercept mixed-effects regression model to determine if there were significant associations between the variables of interest and the elbow varus moment. All moments are presented as internal moments. Results: A total of 78 collegiate level pitchers with a mean age of 19.9 ± 1.3 years, were include in this study. The average fastball velocity was 32.1 ± 2.5m/s. The results indicated that there was no association with the forearm’s position or rotational velocity and the elbow varus moment. However, there were statistically significant associations between the forearm supination moment and the elbow varus moment (p=0.002). The results showed that for every 1Nm increase in the supination moment there was a corresponding 1 Nm increase in the elbow varus moment. Whereas a pronation moment was associated with a decrease in the elbow varus moment (p=0.013). Conclusion: The forearm’s absolute position was not associated with an increased elbow varus moment, indicating that the position of the forearm does not play a role in injury mechanisms for baseball pitchers. However the regression analysis indicated a significant association with the forearm moments and the elbow varus moment. Specifically that an increased supination moment increased the elbow varus moment. Therefore as the body resists the pronation motion associated with pitching this increases the stresses on the medial side of the elbow. Suggesting that an increased need to resist pronation in pitchers that over supinate their arms during a pitch could be placing additional stresses on their elbows and therefore increasing their risk for injury. This finding also provides evidence that a potential injury prevention strategy for pitchers could be to increase their forearm supination and reduce the speed at which they pronate especially during the deceleration of the pitch cycle. </jats:sec
A Biomechanical Analysis of the Association Between Forearm Mechanics and the Elbow Varus Moment in Collegiate Baseball Pitchers
No full textBackground: The incidence of upper extremity injury in baseball pitchers has increased over the past decade. This has resulted in a large body of research mainly focused on the kinematic and kinetic patterns of the elbow and shoulder to elucidate the cause of these injuries, with little attention on studying the associations of forearm rotation and upper arm joint moments. Hypothesis: There will be significant differences in forearm kinematics and kinetics when comparing the fastball pitch with the curveball pitch. There will be a positive association between forearm kinetics, specifically supination and pronation moments, and the elbow varus moment. Study Design: Descriptive laboratory study. Methods: A total of 78 pitchers were recruited for this study, and they underwent a pitching analysis using motion analysis techniques. A random-intercept, mixed-effects regression model was used to determine differences in forearm kinematics and kinetics when pitching a fastball compared with a curveball, as well as to determine if associations existed between forearm supination and pronation moments and the elbow varus moment. Results: There were a number of significant differences in forearm position when pitching a fastball compared with a curveball, with the curveball producing a more supinated forearm position. Significant associations were found between increasing forearm supination moments and an increase in elbow varus moment for both the fastball and the curveball ( P = .002 and P < .001, respectively). For every 1-N·m increase in the supination moment, there was a 1-N·m and 1.1-N·m increase in the elbow varus moment for the fastball and curveball, respectively. Conclusion: The results demonstrated that the forearm position was not associated with the elbow varus moment. However, the supination moment was associated with the elbow varus moment. Clinical Relevance: On the basis of these findings, pitching coaches and trainers can understand the implications of proper lower arm pitching mechanics in the later portion of the pitch cycle as a potential risk of injury and, therefore, can develop coaching strategies to reduce incorrect positioning, especially when players are pitching the curveball. </jats:sec
Multiple risk factors are associated with an incremental increase in acute venous thromboembolism risk after total joint arthroplasty: A pearldiver cohort study.
No full textIntroductionSeveral risk factors are associated with acute venous thromboembolism (VTE) after total joint arthroplasty (TJA). However, there is a lack of literature regarding the cumulative impact of multiple risk factors. To address this gap, we utilized the PearlDiver database, an insurance billing claims database containing de-identified data from 91 million orthopedic patients.MethodsThe PearlDiver database was queried for records of patients who underwent total hip and knee arthroplasty from 2010 to 2019 using ICD-10 and CPT codes. Twelve persistent and two transient risk factors were analyzed for their association with the occurrence of acute VTE within three months after surgery. Univariate and logistic regression analyses with odds ratios (ORs) and confidence intervals (CIs) were conducted to determine the odds associated with each risk factor and the impact of multiple concurrent risk factors.ResultsA total of 988,675 patients who underwent hip and knee arthroplasty met the inclusion criteria, of whom 1.5% developed acute VTE after three months. The prevalence of VTE risk factors ranged from 0.2 to 38.6%. Individual, persistent risk factors demonstrated 14-84% increased odds of VTE compared to a 1.2% increase for a transient risk factor (acute myocardial infarction). Three or more persistent risk factors were associated with a higher risk of VTE.Conclusion and relevancePersistent risk factors were associated with a higher incidence of postoperative VTE than transient risk factors. An incremental increase in risk was noted if three or more persistent risk factors were present
