LJM TBL 2

Which part of the gait cycle follows terminal stance?

Pre-swing

Which muscles are responsible for initiating hip flexion during swing?

Iliopsoas

Which muscle group eccentrically controls knee flexion during swing?

Hamstrings

What defines cadence in gait analysis?

Steps per minute

What is stride length?

Distance between two successive heel strikes of the same foot

Which gait parameter increases with aging?

Duration of double support

What is considered the most energy-efficient walking speed?

Approximately 1.3 m/s

What is a common cause of asymmetrical gait patterns?

Unilateral neurological or musculoskeletal conditions

Which muscle group controls forward trunk motion during heel strike?

Gluteus maximus

What is the function of the quadriceps during loading response?

Control knee flexion and absorb shock

Which part of the CNS coordinates voluntary gait movements?

Motor cortex

Which part of the CNS ensures balance and coordination during walking?

Cerebellum

What sensory input is critical for adjusting gait to surface changes?

Proprioception

What is the role of the basal ganglia in gait?

Initiating and regulating automatic walking movements

What is an early gait abnormality in Parkinson’s disease?

Reduced arm swing

What change in gait may occur due to knee OA?

Reduced stance time on the affected side

Which plane of motion is primary during gait?

Sagittal plane

What is the kinetic chain?

Sequential movement and force transmission across joints

What is the normal range for step width in adults?

5–10 cm

What is the key determinant of stride length?

Leg length and hip mobility

What test evaluates functional gait performance?

Timed Up and Go (TUG) test

What gait is commonly observed in cerebral palsy?

Spastic diplegic gait

What is a festinating gait?

Short, accelerating steps with forward-leaning trunk

Which test is used to assess gluteus medius function?

Trendelenburg test

What structure fails in ACL injury?

Intra-articular ligament of the knee

Which motion does the ACL primarily resist?

Anterior translation of tibia on femur

Which ligament is extra-articular and stabilizes the medial knee?

Medial collateral ligament (MCL)

Which direction does the PCL resist?

Posterior translation of tibia on femur

What commonly causes PCL injury?

Dashboard injury in car accidents

Which test confirms PCL integrity?

Posterior drawer test

What are the zones of ligament healing?

Inflammation, proliferation, remodeling

Which vitamin is essential for collagen synthesis?

Vitamin C

Which enzyme breaks down damaged collagen during healing?

Collagenase

What is a common complication of ligament rupture?

Chronic joint instability

What is the name for excessive joint movement beyond the normal range?

Hypermobility

What is the effect of immobilization on ligaments?

Decreased collagen alignment and strength

What is the preferred surgical graft for ACL reconstruction?

Hamstring or patellar tendon autograft

What is proprioceptive training used for in ligament injury rehab?

Restores neuromuscular control

Which imaging modality can assess ligament morphology?

MRI

Which two features define synovial joints?

Articular cartilage and synovial fluid

What is the role of lubricin in synovial fluid?

Reduces friction between cartilage surfaces

What contributes to synovial fluid’s non-Newtonian behavior?

Hyaluronic acid polymer chains

What is the source of synovial fluid production?

Synoviocytes (type B)

What is the appearance of OA synovial fluid?

Clear, viscous, non-inflammatory

Which parameter helps identify septic arthritis?

WBC count >50,000/mm³

Which diagnostic feature differentiates pseudogout from gout?

Crystal shape and birefringence

What blood test may support a diagnosis of septic arthritis?

Elevated CRP and ESR

What is the first management step in suspected septic arthritis?

Urgent joint aspiration

What imaging supports diagnosis of effusion?

Ultrasound

What finding on X-ray suggests chronic OA?

Subchondral sclerosis

What causes osteophyte formation?

Bone remodeling in response to cartilage loss

What is the mechanism of cartilage degradation in OA?

Enzymatic breakdown by MMPs and cytokines

Which cytokine is heavily involved in OA pathogenesis?

IL-1

What systemic sign is absent in OA but common in RA?

Fatigue or malaise

What does MRI show in early OA not seen on X-ray?

Cartilage thinning and bone marrow edema

What is the most important non-pharmacologic intervention in knee OA?

Weight loss

Which analgesic is avoided in renal disease?

Oral NSAIDs

What defines functional OA severity?

Impact on daily activities and pain level

Which scoring system evaluates OA surgical outcomes?

Oxford Knee Score (OKS)

What is a contraindication to joint replacement?

Active joint infection

What complication of joint replacement occurs years later?

Prosthetic loosening or wear

What does the PROM in JointCalc stand for?

Patient-Reported Outcome Measure

What is an early complication after hip replacement?

Dislocation

What should always be monitored post-operatively in joint surgery?

DVT and PE risk

What is the use of prophylactic anticoagulation in joint surgery?

Prevents thromboembolism

What is an example of lifestyle advice in OA?

Low-impact exercise like swimming

What is the benefit of strengthening quadriceps in OA?

Improves knee stability and reduces pain

What defines acceleration in physics?

Change in velocity per unit time

What defines Newton's Second Law?

Force = mass × acceleration

What is the unit of force?

Newton (N)

What is impulse in biomechanics?

Force applied over time

What is the mechanical advantage of levers in joints?

Allows small muscle force to move large loads

What determines torque?

Force × perpendicular distance from axis

Which variable changes during concentric muscle contraction?

Muscle shortens

Which variable changes during eccentric muscle contraction?

Muscle lengthens while generating force

What type of motion is the femur during hip rotation?

Angular motion

What happens to acceleration when mass increases and force is constant?

It decreases

What type of joint movement occurs in the knee during flexion?

Angular displacement

What is static equilibrium?

Net force and net torque both equal zero

What is a vector quantity?

A quantity with magnitude and direction

What is the benefit of longer limb levers?

Increased torque generation

What is inertia?

Tendency of a body to resist changes in motion

What is the first phase of muscle force production?

Isometric tension buildup

What is the biomechanical definition of work?

Force × displacement

What unit is used for power?

Watt (W)

Which gait deviation results from leg length discrepancy?

Circumduction

What defines swing time?

Time from toe-off to next heel strike of same foot

What is vaulting gait?

Excessive plantarflexion to clear opposite limb

What is scissoring gait associated with?

Spasticity of hip adductors

What is a high steppage gait compensating for?

Foot drop

What is the key functional purpose of the stance phase?

Weight bearing and support

What does a wide-based gait suggest?

Balance or cerebellar dysfunction

Which part of the body acts as a pendulum during walking?

Lower limb during swing

What phase of gait is absent in running?

Double support

What adaptation improves efficiency in long-distance walking?

Elastic recoil of tendons

Which joint absorbs impact at heel strike?

Ankle and subtalar joint

Which test evaluates functional lower limb strength?

Chair stand test

What causes reduced stride length in elderly patients?

Decreased joint mobility and strength

What is the primary lubricant in synovial fluid?

Hyaluronic acid

What is the normal appearance of synovial fluid?

Clear and viscous