Finite element analysis of a healthy knee joint at deep squatting for the study of tibiofemoral and patellofemoral contact.

Background: In non-western countries, deep squatting is a daily activity, and prolonged deep squatting is common among occupational squatters. Household tasks, taking a bath, socializing, using toilets, and performing religious acts are among the activities frequently carried out while squatting by the Asian population. High knee loading is responsible for a knee injury and osteoarthritis. Finite element analysis is an effective tool to determine stresses on the knee joint. Methods: Magnetic Resonance Imaging (MRI) and Computed Tomographic (CT) images were acquired of one adult without knee injuries. The CT images were acquired at the fully extended knee and one more set of images was acquired with the knee at a deeply flexed knee position. The MRI was acquired with the fully extended knee. 3-Dimensional models of bones were created using CT and soft tissue using MRI with the help of 3D Slicer software. Kinematics and finite element analysis of the knee was performed for standing and deep squatting posture using Ansys Workbench 2022. Results: High peak stresses were observed at deep squatting compared to standing along with the reduction in the contact area. Peak von Mises stresses on femoral cartilage, tibial cartilage, patellar cartilage, and meniscus were increased from 3.3 MPa to 19.9 MPa, 2.9 MPa to 12.4 MPa, 1.5 MPa to 16.7 MPa and 15.8 MPa to 32.8 MPa respectively during deep squatting. Posterior translation of 7.01 mm, and 12.58 mm was observed for medial and lateral femoral condyle respectively from full extension to 153° knee flexion. Conclusions: Increased stresses in the knee joint at deep squat posture may cause cartilage damage. A sustained deep squat posture should be avoided for healthy knee joints. More posterior translations of the medial femoral condyle at higher knee flexion angle warrant further investigation.

Estimation and Comparison of Knee Joint Contact Forces During Heel Contact and Heel Rise Deep Squatting.

Background: Increased knee flexion is required for deep squatting in the daily life of the non-western population as well as in many sports activities. The purpose of this study was to estimate as well as to compare knee joint contact forces during heel contact (HC) and heel rise (HR) deep squatting in 10 healthy young Indian participants. Materials and Methods: Kinematic data were captured using a 12-camera Motion Analysis system. Kinetic data were collected using two Kistler force plates. EMG of 6 lower limb muscles was monitored by Noraxon wireless EMG. OpenSim musculoskeletal model was customized to increase the maximum knee flexion capability of the existing model and knee joint contact forces were estimated. Results: A significant difference in tibiofemoral (p < 0.001) as well as patellofemoral (p = 0.006) knee joint contact force was observed between HC and HR squatting. The resultant maximum tibiofemoral KJCF was 5.9 (± 0.54) times body weight (BW) and 5.3 (± 0.6) BW for the HC and HR, respectively. The resultant maximum patellofemoral KJCF was 7.8 (± 0.57) BW and 7.1 (± 0.73) BW for the HC and HR, respectively. Conclusion: The findings can provide implications for physiotherapists to design rehabilitation exercise protocols, exercise professionals, and the development of high flexion knee implants. Supplementary Information: The online version contains supplementary material available at 10.1007/s43465-022-00798-y.

Impact of COVID Pandemic on the Children with Cerebral Palsy.

Background: The COVID pandemic has been raging across the world for the past 18 months and has severely impacted healthcare and resources. Children with special needs have been adversely affected by the COVID pandemic, due to lack of formal schooling, access to rehabilitation and limited physical and social activity. The aim of this online survey was to understand the effect of the pandemic on the children with Cerebral Palsy (CP). Methods: An online survey was conducted using a nine parts questionnaire comprising 26 questions. Survey included questions pertaining to demographic data, ambulatory status, lack of access to physiotherapy, orthotic adjustment, surgery, deterioration of function, and behaviour. A simple binary answer was sought to cover all social strata of society. Results: Responses were received from 101 caregivers who participated in an online questionnaire. 25.7% had no therapy sessions, 74.2% were on therapy of which 23.7% had online sessions. The lockdown restrictions coupled with lack of rehabilitation and orthotic support led to deterioration in physical function in 54 children and worsening of deformity in 34. Changes in behavioural pattern was observed in 45 children. Conclusion: The survey revealed major disruptions in the care of Children with CP. The parents reported difficulties in managing the child therapy at home. There is always a possibility that the pandemic will result in a lockdown again, and hence our approach toward physical therapy assessment and rehabilitation needs to be towards home-based and family-centred care.

Clinical outcome of shoulder muscle transfer for shoulder deformities in obstetric brachial plexus palsy: A study of 150 cases.

BACKGROUND: Residual muscle weakness, cross-innervation (caused by misdirected regenerating axons), and muscular imbalance are the main causes of internal rotation contractures leading to limitation of shoulder joint movement, glenoid dysplasia, and deformity in obstetric brachial plexus palsy. Muscle transfers and release of antagonistic muscles improve range of motion as well as halt or reverse the deterioration in the bony architecture of the shoulder joint. The aim of our study was to evaluate the clinical outcome of shoulder muscle transfer for shoulder abnormalities in obstetric brachial plexus palsy. MATERIALS AND METHODS: One hundred and fifty patients of obstetric brachial plexus palsy with shoulder deformity underwent shoulder muscle transfer along with anterior shoulder release at our institutions from 1999 to 2007. Shoulder function was assessed both preoperatively and postoperatively using aggregate modified Mallet score and active and passive range of motion. The mean duration of follow-up was 4 years (2.5-8 years). RESULTS: The mean preoperative abduction was 45° ± 7.12, mean passive external rotation was 10° ± 6.79, the mean active external rotation was 0°, and the mean aggregate modified Mallet score was 11.2 ± 1.41. At a mean follow-up of 4 years (2.5-8 years), the mean active abduction was 120° ± 18.01, the mean passive external rotation was 80° ± 10.26, while the mean active external rotation was 45° ± 3.84. The mean aggregate modified Mallet score was 19.2 ± 1.66. CONCLUSIONS: This procedure can thus be seen as a very effective tool to treat internal rotation and adduction contractures, achieve functional active abduction and external rotation, as well as possibly prevent glenohumeral dysplasia, though the long-term effects of this procedure may still have to be studied in detail clinico-radiologically to confirm this hypothesis. LEVEL OF EVIDENCE: Therapeutic level IV.