Predicting Knee Joint Contact Force Peaks During Gait Using a Video Camera or Wearable Sensors.

Purpose: Estimating loading of the knee joint may be helpful in managing degenerative joint diseases. Contemporary methods to estimate loading involve calculating knee joint contact forces using musculoskeletal modeling and simulation from motion capture (MOCAP) data, which must be collected in a specialized environment and analyzed by a trained expert. To make the estimation of knee joint loading more accessible, simple input predictors should be used for predicting knee joint loading using artificial neural networks.

Perspectives on reasons why football and handball players sustain acute and severe knee injuries: a mixed-methods concept mapping study.

Background: The high incidence of knee injuries in football/handball challenges effective prevention. Identifying tangible and modifiable factors associated with a knee injury may innovate preventive actions. Engaging key stakeholders can reveal crucial insights that could improve knee injury prevention in football/handball.

Injury Prevention Training in Girls' and Women's Elite Football in Denmark: A Survey of Practices and Perceptions.

Through a national cross-sectional survey, the present study investigated the use and content of injury prevention training (IPT), and associated attitudes and beliefs, involving stakeholders in Danish girls' and women's elite football (U14, U16, U18, and Danish Women's League teams). A total of 168 stakeholders (coaches, physical performance coaches, physiotherapists, medical doctors, and club management) from 18 Danish elite clubs were invited to participate. Of these, 158 were eligible to participate, and 110 participants (69.

Corrigendum: Non-invasive methods to assess muscle function in dogs: a scoping review.

[This corrects the article DOI: 10.3389/fvets.2023.

Muscle function assessment of the hindlimbs in healthy dogs using acoustic myography.

Introduction: Impaired muscle function is a frequent consequence of musculoskeletal disorders in dogs. Musculoskeletal disorders, especially stifle joint diseases, are common in dogs and assessment of muscle function in dogs is clinically relevant. Acoustic myography (AMG) is a non-invasive method to assess muscle activity.

Sensitivity of simulated knee joint mechanics to selected human and bovine fibril-reinforced poroelastic material properties.

Fibril-reinforced poroviscoelastic material models are considered state-of-the-art in modeling articular cartilage biomechanics. Yet, cartilage material parameters are often based on bovine tissue properties in computational knee joint models, although bovine properties are distinctly different from those of humans. Thus, we aimed to investigate how cartilage mechanical responses are affected in the knee joint model during walking when fibril-reinforced poroviscoelastic properties of cartilage are based on human data instead of bovine.

Prediction of Knee Joint Compartmental Loading Maxima Utilizing Simple Subject Characteristics and Neural Networks.

Joint loading may affect the development of osteoarthritis, but patient-specific load estimation requires cumbersome motion laboratory equipment. This reliance could be eliminated using artificial neural networks (ANNs) to predict loading from simple input predictors. We used subject-specific musculoskeletal simulations to estimate knee joint contact forces for 290 subjects during over 5000 stance phases of walking and then extracted compartmental and total joint loading maxima from the first and second peaks of the stance phase.

Evaluation of hop performance in children with anterior cruciate ligament reconstruction using healthy reference data: A cross-sectional study.

Background: Hop performance evaluation in children after anterior cruciate ligament (ACL) reconstruction may benefit from comparison to healthy controls. Thus, the purpose was to investigate the hop performance in children one year after ACL reconstruction with a comparison to healthy controls.

Methods: Hop performance data from children with ACL reconstruction one year post-surgery and healthy children were compared.

Non-invasive methods to assess muscle function in dogs: A scoping review.

Skeletal muscle function can be affected by multiple disorders in dogs of which cranial cruciate ligament rupture or disease (CCLD) is one of the most common. Despite the significance of this condition only sparse research exists regarding assessment of muscle function in dogs. This scoping review aimed to identify the non-invasive methods for canine muscle function assessments that have been reported in the literature in the past 10 years.

Altered movement strategy during functional movement after an ACL injury, despite ACL reconstruction.

Knee joint functional deficits are common after anterior cruciate ligament (ACL) injury, but different assessment methods of joint function seem to provide contradicting information complicating recovery monitoring. We previously reported improved perceived knee function and functional performance (forward lunge ground contact time) in patients with an ACL injury from pre to 10 months post ACL reconstruction without improvement in knee-specific biomechanics. To further investigate this discrepancy, we additionally analyzed knee extensor and flexor muscle strength, and movement quality in the forward lunge (subjective and objective evaluations) and performed a full lower limb biomechanical analysis of the forward lunge movement.

Reference data for hop tests used in pediatric ACL injury rehabilitation: A cross-sectional study of healthy children.

In rehabilitation, four single-leg hop tests are frequently used for evaluation of ACL-injured children. However, reference values on single-leg hop performance and the corresponding limb symmetry indexes (LSIs) of healthy children younger than 15 years of age are lacking. Thus, the purpose was to describe hop performance and LSIs in healthy Danish children, and to quantify the proportion of participants passing LSI values of ≥85% as well as ≥90%.

Influence of Wearing Ballistic Vests on Physical Performance of Danish Police Officers: A Cross-Over Study.

Purpose: We aimed to investigate the influence of wearing a ballistic vest on physical performance in police officers.

Methods: We performed a cross-over study to investigate the influence of wearing a ballistic vest on reaction and response time, lumbar muscle endurance and police vehicle entry and exit times. Reaction and response time was based on a perturbation setup where the officers' pelvises were fixed and EMG of lumbar and abdominal muscles was recorded.

The influence of an orthopaedic walker boot on forefoot force.

Background: In the treatment of an Achilles tendon rupture the patients are commonly equipped with an orthopaedic walker boot with wedges. To what extent this influences the tensile force placed on the Achilles tendon is unclear.

Purpose: To assess the forefoot force and describe changes in muscle activity of the medial gastrocnemius, soleus and tibialis anterior when using one or three wedges during ambulation in a weightbearing orthopaedic walker boot.

Functional muscle synergies to support the knee against moment specific loads while weight bearing.

Objective: Externally applied abduction and rotational loads are major contributors to the knee joint injury mechanism; yet, how muscles work together to stabilize the knee against these loads remains unclear. Our study sought to evaluate lower limb functional muscle synergies in healthy young adults such that muscle activation can be directly related to internal knee joint moments.

Methods: Concatenated non-negative matrix factorization extracted muscle and moment synergies of 22 participants from electromyographic signals and joint moments elicited during a weight-bearing force matching protocol.

Effect of footwear on intramuscular EMG activity of plantar flexor muscles in walking.

One of the purposes of footwear is to assist locomotion, but some footwear types seem to restrict natural foot motion, which may affect the contribution of ankle plantar flexor muscles to propulsion. This study examined the effects of different footwear conditions on the activity of ankle plantar flexors during walking. Ten healthy habitually shod individuals walked overground in shoes, barefoot and in flip-flops while fine-wire electromyography (EMG) activity was recorded from flexor hallucis longus (FHL), soleus (SOL), and medial and lateral gastrocnemius (MG and LG) muscles.

Evaluation of abdominal exercises after stoma surgery: a descriptive study.

Purpose: To evaluate the feasibility of exercises for the abdominal muscles in patients after colostomy or ileostomy formation on the following parameters: muscle activity, pain, discomfort, and difficulty of performing the exercises.

Materials And Methods: Patients with a new stoma were divided into groups based on time after surgery: Early group, 0-2 weeks ( = 12); Intermediate group, 2-6 weeks ( = 15); and Late group, 6-12 weeks ( = 10). During a single individual test session, participants in each group performed a different set of 10-11 abdominal coordination and strengthening exercises for the abdominal muscles.

Dynamics of Postural Control in Elite Sport Rifle Shooters.

Thirteen shooters and eleven non-shooters completed two-legged and single-legged stance on a force platform. The dynamics of the center of pressure trajectory was assessed using sample entropy, correlation dimension and entropic half-life. Additionally, the body sway was quantified as the elliptical area of the trajectory.

Forward lunge before and after anterior cruciate ligament reconstruction: Faster movement but unchanged knee joint biomechanics.

The forward lunge (FL) may be a promising movement to assess functional outcome after ACL reconstruction. Thus, we aimed to investigate the FL movement pattern before and after ACL reconstruction with a comparison to healthy controls to determine if differences were present. Twenty-eight ACL injured participants and 28 matched healthy controls were included.

Relationship of Knee Forces to Subjective Function Pre- and Post-ACL Reconstruction.

Purpose: Although basic objective measures (e.g., knee laxity, strength, and hop tests) have been related to subjective measures of function, associations between knee-specific objective and subjective measures have yet to be completed.

Predicting post-operative functional ability from pre-operative measures in ACL-injured individuals.

Purpose: This study aimed to quantify the relationship between objective and subjective measures of functional ability and determine if measures in the deficient (ACLd) state were correlated to, and capable of predicting a patient's objective and subjective measures in the reconstructed (ACLr) state.

Methods: Twenty ACL-injured participants completed hop and side cut movements prior to and 10 months post-reconstruction. Their subjective measures (Tegner, Lysholm, IKDC, KOOS, and KNEEs) were related to objective measures of functional ability (peak knee flexion, peak knee extensor moment, stiffness, knee joint center excursion (KJCE), and knee joint center boundary).

Knee osteoarthritis among airport baggage handlers: A prospective cohort study.

Background: Knee osteoarthritis is a common and often disabling disorder, which has been related to knee-straining work. However, exposure response relations are uncertain and there are few prospective studies. We studied prospectively if incident knee osteoarthritis is associated with cumulative exposure as an airport baggage handler, lifting on average 5000 kg/d.

Occupational lifting predicts hospital admission due to low back pain in a cohort of airport baggage handlers.

Purpose: To examine if occupational lifting assessed as cumulative years as a baggage handler is associated with first-time hospital diagnosis or treatment for low back disorders.

Methods: This study is based on the Copenhagen Airport Cohort consisting of male baggage handlers performing heavy lifting every day and a reference group of unskilled men from the greater Copenhagen area during the period 1990-2012. We followed the cohort in the National Patient Register and Civil Registration System to obtain information on diagnoses, surgery, mortality, and migration.