A method to improve the calculation of knee configuration angles in clinical and sport biomechanics

Knee injuries are quite common in sports activities. Biomechanical analyses seek to improve understanding of the mechanisms that produce injury, and to find ways to reduce the incidence of injury. The calculation of knee torques and knee configurations requires the establishment of three-dimensional reference frames attached to the thigh and to the shank. Most clinical biomechanics researchers use the methods proposed by Kadaba et al. (1990) and by Davis and al. (1991). The calculation of the resultant knee joint torques and of the knee joint deformation is hampered by an important methodological problem. The problem is that usually no distinction is made between knee configuration angles and knee deformation angles. The primary purpose of this study was to look for a solution to this problem. Ten male subjects and four female subjects were recruited to participate in the investigation. The subjects performed three types of tests. In the first type the subject performed slow flexions and slow extensions of the right knee in unloaded conditions. In the second type of test they performed a series of 4 straight runs. In the third type of test they performed a series of 4 trials in which they ran forward and executed a cutting maneuver to the left. The trials of types 2 and 3 were given in random order. Three-dimensional leg segment orientations and joint angles were calculated from the landmark location data. v The results support the measurement of angles in unloaded trials to provide adjustments for the raw ab/adduction angles of loaded activities. On the other hand, such an approach is not currently possible for the internal/external rotation angles due to the large intra-subject variability of the internal/external rotation angles in the unloaded trials. The adjusted ab/adduction angles generally reached less extreme values than the unadjusted ones. The standard Kadaba/Davis methods do not include such adjustments. Therefore, the ab/adduction angles calculated with those methods are inflated. In summary, the present project demonstrated a new method for improving the calculation of knee configuration angles. These results can be applied in both clinical and sport biomechanics in ways that will ultimately be of benefit in the future study and treatment of knee injuries.Submitted to the faculty of the Graduate School In partial fulfillment of the requirements For the Master of Science degree in the School of Health, Physical Education, and Recreation Indiana University May, 201

A Novel Method for Calculation of Knee Deformation Angles in Clinical and Sport Biomechanics

Biomechanical analyses seek to improve understanding of the mechanisms of knee injury and to find ways to reduce knee injury incidence. Many clinical biomechanics researchers use a standard kinematic adopted from Newington Children’s Hospital. Biomechanical studies include the knee joint configurations, where joint architecture immutably constrains and guides movement outcomes. Investigators will default to reporting resultant joint deformation without considering the influence of joint architectural configurations on kinematic responses. The purpose of this study was to develop a new joint angular kinematic method that accounts for influence of dynamic joint architectural configuration on deformation values. Twenty subjects performed unloaded dynamic flexion/ extension and 45° cutting maneuver. The knee deformation angles obtained with the new method proposed were compared with the values that obtained using the standard method. One way repeated measurement ANOVA’s was used to compare knee deformation angles values from the standard method that uses a static trial and the new method that uses a dynamic trial. The proposed method distinguishes between dynamic joint architectural configuration and joint deformation. Loaded standard abduction/adduction (β) and rotation (γ) angles were 3.4 ±1.8° and 11.2 ±3.8°, respectively. Using the new method, the β and γ angles decrease to 1.5 ±1.4° (<0.05) and 7.1 ±1.8° (<0.05) during cutting. The new method accounted for dynamic joint architectural configuration produced loaded β and γ angles that had smaller magnitudes than the standard method, suggesting that previous studies may have overestimated β and γ angles. Injury management strategies could be influenced by a consideration for dynamic joint architectural configuration. Such a consideration could influence ligament repair strategies. Future studies should account for dynamic configuration when establishing the influence of joint deformation on graft design and appropriate isometry values during reconstruction

Effects of Gender and Recurrent Low Back Pain on Lifting Style

Objective: The purpose of this study was to examine the influence of gender and existing, recurrent low back pain (rLBP) on lower extremity and trunk mechanics, as well as neuromuscular control, during a lift task. Design: A multivariate design was used to examine the effects of gender and group on biomechanical and neuromuscular control variables in randomized symmetric and asymmetric lifting. Methods: 68 Males and females with rLBP and healthy performed symmetric and asymmetric weighted box lifting trials to a 1 meter height table. Results: Lifting style was different between gender and between the rLBP versus healthy groups during a 1m box lifting. A significant two-way interaction effect between gender and group was observed for multifidus muscle activity and knee rotation in asymmetric lifting. Several gender and group main effects were observed in pelvis obliquity, trunk flexion and side flexion, knee abduction angles in symmetric lifting; and in pelvis obliquity and rotation, trunk flexion and side flexion, hip abduction, knee abduction angles, external oblique and internal oblique muscles activity in asymmetric lifting. Conclusions: Females and individuals with rLBP appear to use different lifting styles that emphasize movement at the pelvis accompanied by poor kinematic control features at the hip, trunk and knee. Clinicians should be mindful of these changes when developing prevention and rehabilitation programs aimed at improving trunk control in preparation for lifting tasks during domestic and occupational activities

Healthcare Engineering Defined: A White Paper

Engineering has been playing an important role in serving and advancing healthcare. The term "Healthcare Engineering" has been used by professional societies, universities, scientific authors, and the healthcare industry for decades. However, the definition of "Healthcare Engineering" remains ambiguous. The purpose of this position paper is to present a definition of Healthcare Engineering as an academic discipline, an area of research, a field of specialty, and a profession. Healthcare Engineering is defined in terms of what it is, who performs it, where it is performed, and how it is performed, including its purpose, scope, topics, synergy, education/training, contributions, and prospects

A Comparison of Muscular Activity During Gait Between Walking Sticks and a Walker in Patients With Adult Degenerative Scoliosis

© 2018 Scoliosis Research Society Study Design: A repeated measurement, single-center, prospective study. Objective: The purpose of this study is to compare and contrast the benefits of walking sticks versus a walker on the trunk and lower extremity muscular control in patients with adult degenerative scoliosis (ADS). Summary of Background Data: ADS patients demonstrate an altered gait pattern. Walking aids help maintain mobility in those patients. Whereas a walker forces patients into kyphosis, the higher grips of walking sticks allows for more upright posture, arm swing, and improved sagittal alignment. Methods: Twenty ADS patients with symptomatic degenerative scoliosis performed over-ground walking at self-selected speed under 3 testing conditions: 1) with walking sticks (WS); 2) with walker (WR); and 3) without any device (ND). Trunk and lower extremity peak muscle activation, time to peak muscle activity, muscle duration, muscle onset, and integrated electromyography (iEMG) were measured and compared. Results: The use of WS produced increases in muscle activity in the external oblique (WS: 44.3% vs. WR: 7.4% of submaximum voluntary contraction [sMVC], p = .007) and medial gastrocnemius (WS: 78.8% vs ND: 43.7% of sMVC, p = .027) in comparison to the walker and no device, respectively. When using WS, shorter muscle activity time was observed for rectus femoris (WS: 62.9% vs. WR: 88.8% of gait cycle, p = .001), semitendinosus (WS: 64.3% vs. WR: 93.0% of gait cycle, p = .003), tibialis anterius (WS: 59.4% vs. WR: 85.1% of gait cycle, p = .001), and medial gastrocnemius (WS: 67.3% vs. WR: 98.0% of gait cycle, p = .006) in comparison to the walker. Conclusions: The use of walking sticks can potentially promote trunk and lower extremity neuromuscular control and gait mechanics comparable to gait without any assistive devices. Although the differences in magnitudes between comparisons were small and should be cautiously interpreted on a case-by-case basis, based on this study\u27s results and our anecdotal experience treating patients with ADS, we recommend the use of walking sticks to assist with their gait prior to and after surgical intervention. Level of Evidence: Level III

Spine Surgeons Social Dilemma: Benefits and Risks of Social Media for Spine Surgery Practice in the 21st Century.

STUDY DESIGN: Cross-sectional observational. BACKGROUND: The use of social media by providers can enhance patient education, complement offline information, facilitate patient support, stimulate brand building, and strengthen the organizations market position. Risks of social media include, but are not limited to, a lack of quality, reliability, misrepresentation of credentials, influence of hidden and overt conflicts of interest, content that may jeopardize patient privacy, HIPAA regulations, and physicians credentials and licensure. Physicians use of social media may also expose him/her to lawsuits if providing specific medical advice on media platforms. OBJECTIVE: To document the social media presence of a broad cohort of spine surgeons, and to discuss the benefits and risks of a social media presence. METHODS: Cross-sectional observational of 325 Spine Surgeons from 76 institutions across the US. Description statistic and Pearsons correlation were used to investigate the relationships between the variables. RESULTS: Out of the 325 surgeons, 96% were male with an average age of 51.5 ± 10.7 years and 14.1 ± 9.6 years of experience. The frequency of social media use included 57.2% of surgeons had professional LinkedIn, 17.8% had professional Facebook, and less than 16% had other social media platforms. When combining all platforms together, 64.6% of all surgeons had at least one professional social media platform. 64.0% of these surgeons had no social media activity in the past 90 days, while 19.4% and 10.9% were active once and twice a month, respectively. Surgeon age (P = 0.004), years in practice (P < 0.001), and practice type (P < 0.001) were strongly correlated with social media activity. CONCLUSIONS: Given the scarcity of research on this topic and the novelty of the platforms, social media and online services continue to be utilized at a low level by spine surgeons. Issues regarding the risks of privacy issues with social media users continue to be a concern among medical professionals adopting this technology. This can largely be mitigated with the combination of physician education and informed consent from patients. The ability to connect with patients directly, and provide access to high-quality education and information will be of considerable benefit to our field well into the future