SAQMG2

The are three articulations in the ankle joint.

The three main ligaments that stabilise the ankle joint are the anteriorinferior talofibular, the medial and lateral ligaments.

Dorsiflexion is flexion of the ankle joint - toes move upwards.

Plantarflexion is extension of the ankle joint - toes move downwards.

The three parts of the foot are the forefoot, the midfoot and the hindfoot. The forefoot is made up of the metatarsals and phalanges. The midfoot is made up of the cuneiforms, the cuboid and the navicular. The hindfoot is made up of the talus and calcaneus.

The bones that form the subtalar joint are the talus and the calcaneus.

Inversion and eversion occur at the subtalar joint.

The ligamentous structure which supports the longitudinal arches of the foot is called the plantar fascia.

Reciprocal gait is the gait most commonly used for walking. During reciprocal gait the lower limbs are used alternatively to provide support and propulsion.

Gait analysis is the examination of gait.

There are three main pieces of equipment found in a gait laboratory. They are a motion analysis system, force plates and electromyography equipment.

A motion analysis system is a device which records the motion of markers placed on a patient, thus allowing the patient's movements to be reconstructed and observed on a computer.

During reciprocal gait the stance phase and the swing phase are bothdefined by the two events: heel contact and toe off.

Double support is the period during the gait cycle when both feet are incontact with the ground.

The events that occur in reciprocal gait are: heel contact, foot flat, midstance, heel off, toe off and mid swing.

The knee joint is the lower limb joint with the greatest range of motionduring reciprocal gait.

The peak amount of dorsiflexion occurs at around heel off.

A force plate is used to measure the ground reaction force exerted on the foot during the stance phase of gait.

The hamstrings contract slightly at heel contact to prevent the hyperextension of the knee.

The four articulations of the shoulder joint are the glenohumeral, acromioclavicular, sternoclavicular and the scapulothoracic.

The shallow depression in which the humeral head rests is called the glenoid fossa.

The ligament about whose attachment the clavicle rotates during elevation and depression is the costoclavicular

The scapulothoracic articulation is not a joint in the truest sense - there are no direct bony or ligamentous connections.

The resistance force must be 10 times the magnitude of the applied force, that is 1000N.

Flexion-extensionExtension: 0°Flexion: 140°Range: 140°Pronation-SupinationPronation: 70°Supination: 80°Range: 150°

Lateral collateral ligament (ligament at the elbow)

Yes, the elbow joint force could be assumed to have both horizontal and vertical components. Summing the horizontal force components would then give a result of zero for the horizontal elbow joint component and summing the vertical forces would give a negative result if the vertical component as defined as acting upwards.

Total body weight = 9.8 × 85 = 833 N.The flexor muscle force is 820 N, therefore it is equal to 0.98 of total body weight.The elbow joint force is 760 N, therefore it is equal to 0.91 of total body weight.

If the flexor muscle force did not act vertically then the elbow joint force would need to have an equal but opposite horizontal component to maintain static equilibrium.

The bones that form the proximal row of the wrist are the triquetrum, lunate and scaphoid and those that form the distal row are the hamate, capitate, trapezoid and trapezium.

The lever arm of the flexor carpi ulnaris muscle is increased by the pisiform bone.

The principal motions of the wrist joint are flexion-extension and adbuction-adduction.

Most wrist extension occurs at the radiocarpal joint.

The most functional position for an immobilised wrist joint is around 15 degrees of extension.