Effect of the position of the interphalangeal joint on movements of the trapeziometacarpal joint during thumb opposition

The Kapandji test is a simple method to score thumb opposition; however, the position of the interphalangeal joint of the thumb during this test has not been described. We aimed to quantitatively examine the effect of the thumb interphalangeal joint position on movements of the trapeziometacarpal joint during thumb opposition using the Kapandji test. The Kapandji test was carried out in 20 healthy participants during thumb interphalangeal joint extension and flexion. Movements of the joints and the activity of thenar muscles were recorded using motion capture and electromyography, respectively. We found that interphalangeal joint extension increased the trapeziometacarpal joint movement and thenar muscle activity compared with interphalangeal joint flexion, which contributed to thumb opposition at Kapandji Positions 0–6. These findings suggest the position of the thumb interphalangeal joint affects the trapeziometacarpal joint during thumb opposition, and assessment of thumb opposition using the Kapandji test is best done with the thumb interphalangeal joint in extension.

Influence of Sex and Knee Joint Rotation on Patellofemoral Joint Stress through a Mathematical Modelling Study

Background: Females are two times as likely to experience patellofemoral pain syndrome (PFPS) than males; however, the reason for this sex difference remains unclear. Patellofemoral joint (PFJ) stress is believed to contribute to PFPS alterations through knee joint rotation alignment, but the influence of knee joint rotation conditions on PFJ stress is unclear. We aimed to investigate the influence of sex and knee joint rotation alignment on PFJ stress. Methods: Simulation ranges were set to knee joint flexion angles of 10°-45° (common to both sexes) and extension moments of 0-240 Nm (males) and 0-220 Nm (females). The quadriceps force and effective lever arm length at the quadriceps muscle were determined as a function of the knee joint flexion angle and extension moment. The PFJ contact area, which is specific to sex, and knee joint rotation was calculated from cadaver data, and PFJ stress was estimated. Results: In all knee joint rotation conditions, PFJ stress was higher in females than in males. Additionally, PFJ stress in males and females was the largest under neutral conditions compared with other rotation conditions. Conclusion: The results may be useful for understanding the underlying mechanisms contributing to the differences in PFPS in males and females.

Bionic arm: Mapping of elbow and wrist flexion using neural network and fuzzy logic

Cases on limb amputation necessitate the use of Transhumeral bionic for artificial limb rehabilitation, which is controlled using Electromyographic (EMG) signals from the muscles. Before the implementation of EMG control, a mapping between the movements of an arm to the angle formed at the corresponding joints is essential to be made. Most of the works in the field of Bionics use Supervised Machine Learning models, chiefly Classification, to map muscle flexion signals to joint actuations in the bionic arm. Ample literature is also there, which uses fuzzy logic for mapping. However, there are very few literatures that compare these two methods of mapping. In this article, 2 models have been discussed regarding the mapping, and their effectiveness is compared. The first model captures elbow and wrist flexion and maps them to their respective angular displacements of joints using a fuzzy logic model. In the second model, a Pattern Recognition Artificial Neural Network (ANN) model under Supervised Machine Learning is incorporated to map elbow and wrist flexion to the corresponding joint angular displacement. The ANN is trained with elbow and wrist joint flexion values and its corresponding joint angles data, optimized, and tested in real-time. This model is verified by comparing the joint angles of a test person (measured using Goniometers) with the joint angles of Bionic models made (using a 360° protractor sheet). The second model gave the insight that supervised machine learning models provide an accurate mapping to the joint flexion in the field of bionics.

Influence of Sex And Knee Joint Rotation On Patellofemoral Joint Stress Through A Mathematical Modelling Study

Background: Females are two times as likely to experience patellofemoral pain syndrome (PFPS) than males; however, the reason for this sex difference remains unclear. Patellofemoral joint (PFJ) stress is believed to contribute to PFPS alterations through knee joint rotation alignment, but the influence of knee joint rotation conditions on PFJ stress is unclear. We aimed to investigate the influence of sex and knee joint rotation alignment on PFJ stress. Methods: Simulation ranges were set to knee joint flexion angles of 10°-45° (common to both sexes) and extension moments of 0-240 Nm (males) and 0-220 Nm (females). The quadriceps force and effective lever arm length at the quadriceps muscle were determined as a function of the knee joint flexion angle and extension moment. The PFJ contact area, which is specific to sex, and knee joint rotation was calculated from cadaver data, and PFJ stress was estimated. Results: In all knee joint rotation conditions, PFJ stress was higher in females than in males. Additionally, PFJ stress in males and females was the largest under neutral conditions compared with other rotation conditions. Conclusion: The results may be useful for understanding the underlying mechanisms contributing to the differences in PFPS in males and females.

Static Balancing Ability and Lower Body Kinematics Examination of Hungarian Folk Dancers: A Pilot Study Investigating the “Kalocsai Mars” Dance Sequence

Folk dance is a collection of traditional dances that requires years of practicing to perform correctly. The aim of the present study was to develop a complex biomechanical measurement procedure that investigated Hungarian folk dancers’ balancing ability and lower body kinematics through a dance movement called “Kalocsai mars”. Therefore, 11 dancers’ motion (5 female and 6 male; age: 20.5 ± 2.5 years; height: 173.82 ± 7.82 cm; weight: 64.77 ± 8.67 kg) was recorded with an optical-based motion capture system and force platforms simultaneously. Before and after the dancing session, static balancing tests were performed, examining bipedal stance with eyes opened and closed conditions. The ANOVA results showed that the values of the range of motions of the knee joint flexion-extension angles and hip flexion averaged for sessions increased significantly (p=0.044, p=0.003, p=0.005) during the dancing sessions. The deviation in the joint angle was greater in the nondominant legs, suggesting that the nondominant side requires more attention to execute the dance steps correctly. The results of the balance tests showed that the oscillation in the posterior direction increased significantly after dancing (p=0.023). In comparison, the visual feedback had no significant effect on the dancers’ balancing ability.

Unique case of anterior interosseous nerve injury following distal volar radial plating: A case report

Trauma itself, surgery, nerve entrapments, amyotrophic neuropathy, or neuritis may result in anterior interosseous nerve (AIN) palsy. A 76-year-old woman who was operated for distal end radius fracture with plating was referred back referred back to the clinic by her general practitioner with complaints of inability to flex the interphalangeal joint of the thumb and index finger approximately 3 years after the index surgery. The proximal interphalangeal joint flexion (flexor digitorum superficialis) of the index finger was intact and the pinch power was reduced. She had normal function of her other forearm and hand muscles. Ultrasonography and nerve conduction velocity (NCV) studies were done to investigate further to rule out either tendon flexor pollicis longus (FPL) or nerve injury (AIN). NCV studies reported subacute denervation within the FPL. The patient recovered to near normal without any surgical intervention in 18 months. Literature reported various treatment options in the form of conservative as well as surgical depending on the cause and evidence of recovery.

DETERMINATION OF THE STRESS OF ANTERIOR CRUCIATE LIGAMENT IN VARIOUS DEGREES OF KNEE FLEXION, COMPARISON OF NORMAL AND RECONSTRUCTED LIGAMENT

Background: Knee joint stability is enhanced by ligamentus structures such as anterior cruciate (ACL), posterior cruciate (PCL), medial collateral (MCL) and lateral collateral ligaments (LCL). Rupture of ACL is the most common knee injuries, especially in sport related activities. The aim of this study is to evaluate the stress developed in knee joint structures in various degrees of knee flexion in ACL ruptured compared to normal condition. Method: CT scan images of knee joint were used to create 3d model of knee joint by use of Mimics software. Abaqus software was used to evaluate the stress developed in knee joint in normal and in ACL reconstructed conditions in various degrees of knee flexion. Results: The stress developed in ACL and other knee joint structures increased significantly by increase in knee joint flexion. The stress of knee joint structures (especially in ACL) in ACL reconstructed condition was more than that of normal condition. Conclusion: It is recommended to immobilize the knee joint in extension up to [Formula: see text] of knee flexion in those with ACL injuries. The stress of ACL increased due to an increase in tibia translation associated with knee flexion.