Ankle and Foot Anatomy PDF
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Fairleigh Dickinson University
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This document discusses the anatomy and function of the ankle and foot, including the bones, joints, and muscles involved. It also details the assessment of the ankle and foot, including palpation techniques.
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Ankle and foot ○ The total weight of the body is transmitted through the ankle to the foot. The ankle and the foot must balance the body and absorb the impact of the heel strike and gait. Despite thick padding along the toes, sole and heel and stabilizing ligaments at the ankles, the a...
Ankle and foot ○ The total weight of the body is transmitted through the ankle to the foot. The ankle and the foot must balance the body and absorb the impact of the heel strike and gait. Despite thick padding along the toes, sole and heel and stabilizing ligaments at the ankles, the ankle and foot are frequent sites of sprain and bony injury The ankle is a hinge joint formed by the tibia, fibula and talus ○ Note the principal landmarks of the ankle: The medial malleolus, the bony prominence of the distal end of the tibia The lateral malleolus, at the distal end of the fibula. Lodged under the talus and jutting posteriorly is the calcaneus or heel bone ○ Movements at the ankle joint is limited to dorsiflexion and plantar flexion Plantar flexion is powered by the gastrocnemius, the soleus, and plantaris, with the tibialis posterior and toe flexors playing supporting roles. The strong achilles tendon attaches the gastrocnemius and soleus muscles to the posterior calcaneus The dorsiflexors include the tibialis anterior and the toe extensors. They lie prominently on the anterior surface, or dorsum of the ankle, anterior to the malleoli ○ Muscles in the lateral compartment are responsible for eversion of the foot and include the fibularis longus and fibularis brevis, which run under the lateral malleolus and move the foot outward ○ Muscles in the medial compartment of the foot are responsible for inversion of the foot (heel bows inward) and include the tibialis posterior and anterior muscles. The tibialis posterior runs just behind the medial malleolus with the toe extensors ○ Ligaments extend from each malleolus onto the foot Medialy, the triangle-shaped deltoid ligament fans out from the inferior surface of the medial malleolus to the talus and proximal tarsal bones, protecting against tress from eversion (heel bows outward) Laterally, the three ligaments are less substantial with higher risk for injury from inversion injuries. They include the anterior talofibular ligaments (often most at risk), the calcaneofibular ligament, and the posterior talofibular ligament The plantar fascia inserts on the medial tubercle of the calcaneous Foot and ankle ○ Eval Inspection Motion Gait Palpation Strength Neuro Special tests Palpation ○ With your thumbs, palpate the anterior aspect of each ankle joint, noting any bogginess, swelling or tenderness Feel along the achilles tendon for nodules and tenderness Palpate the heel, especially the posterior and inferior calcaneus and the plantar fascia for tenderness Palpate for tenderness over the medial and lateral ankle ligaments and the medial and lateral malleolus, especially in the cases of trauma In trauma the distal tips of the tibia and fibula should also be palpated Palpate the MTP joints for tenderness. Compress the forefoot between teh thumb and fingers. Exert pressure just proximal to the heads of the first and 5th metatarsals Palpate the heads of the 5 metatarsals and the grooves between them with your thumb and index finger. Place your thumb on the dorsum of the foot and your index finger on the plantar surface. Move the metatarsal heads relative to each other, evaluating both for increased laxity and pain with motion Palpate the gastrocnemius and soleus muscles on the posterior lower leg. Their common tendon, the Achilles, is palpable from about the lower third of the calf to its insertion on the calcaneus The shoulder ○ The shoulder derives its mobility from a complex interconnected structure of: 4 joints Three large bones Three principle muscle groups Often referred to as the shoulder girdle ○ These structures are viewed as dynamic stabilizers which are capable of movement, or static stabilizers, which are incapable of movement ○ ○ The body structures of the shoulder: Humerus, clavicle, scapula The scapula is anchored to the axial skeleton only by the sternoclavicular joint and inserting muscles, often called scapulothoracic articulation because the sternoclavicular joint is not a true joint ○ Three different joints articulate at the shoulder: The glenohumeral joint: In this joint, the head of the humerus articulates with the shallow glenoid fossa of the scapula. This joint is deeply situated and normally not palpable. It is a ball-and-socket joint, allowing the arm its wide arc of movement Sternoclavicular joint: the convex medial end of the clavicle articulates with the concave hollow in the upper sternum Acromioclavicular joint: the lateral end of the clavicle articulates with the acromion process of the scapula ○ Three groups of muscle attach at the shoulder: rotator cuff disorders are the most common cause of shoulder pain in primary care ○ SITS muscles of the rotator cuff: Supraspinatus – originates on the posterior scapula superior to the scapular spine and runs above the glenohumeral joint; inserts on the greater tubercle Infraspinatus and teres minor – originate on the posterior scapula inferior to the scapular spine and cross the glenohumeral joint posteriorly; inserts on the greater tubercle Subscapularis – originate on the anterior surface of the scapula and crosses the joint anteriorly; inserts on the lesser tubercle ○ Inspection Inspect the shoulder and shoulder girdle anteriorly, then the scapulae and related muscles posteriorly Note any swelling, deformity, muscle atrophy, or fasciculations (fine tremors of the muscles) or abnormal positioning Look for swelling of the joint capsule anteriorly or a bulge in the subacromial bursa under the deltoid muscles. Survey the entire upper extremity for color change, skin alteration, or unusual bony contrours When the shoulder muscles appear atrophic, inspect for scapular winging. Ask the patient to extend both arms and push against your h and or against a wall. Observe the scapulae, normally they lay close to the thorax In winging, the medial border of the scapula juts backward, suspicious for weakness of the trapezius or serratus anterior muscle (seen in muscular dystrophy) or injury to the long thoracic nerve. In very thin individuals, the scapulae may appear “winged” even when the musculature is intact ○ Palpation Being by palpating the bony contours and structures of the shoulder, then palpate any area of pain Beginning medially, at the sternoclavicular joint, trace the clavicle laterally with your fingers to the acromioclavicular joint From behind, follow the bony spine of the scapula laterally and upward until it becomes the acromion, the summit of the shoulder. Its upper surface is rough and slightly convex. Identify the anterior tip of the acromion With your index finger on top of the acromion, just behind its tip, press medially with your thumb to find the slightly elevated ridge that marks the distal end of the clavicle at the acromioclavicular joint. Move your thumb medially and down a short step to the next bony prominence, the coracoid process of the scapula With your thumb on the coracoid process, allow your fingers to fall on and grasp the lateral aspect of the humerus to palpate the greater tubercle where the SITS muscles insert Next, to palpate the biceps tendon in the intertubercular bicipital groove of the right shoulder, keep your thumb on the coracoid process and your fingers on the lateral aspect of the humerus (Fig. 23-18). Remove your index finger and place it halfway between the coracoid process and the greater tubercle on the anterior surface of the arm. As you check for tendon tenderness, rolling the tendon under the fingertips may be helpful. You can also rotate the glenohumeral joint externally, locate the muscle distally near the elbow, and track the muscle and its tendon proximally into the intertubercular groove. To examine the subacromial subdeltoid bursa and the SITS muscles, first passively extend the humerus by lifting the elbow posteriorly, which rotates these structures so that they are anterior to the acromion. Palpate carefully over the subacromial and subdeltoid bursae ○ The underlying palpable SITS muscles are: Supraspinatus—directly under the acromion, also traceable from the muscle belly above the scapular spine posteriorly I nfraspinatus—posterior to supraspinatus, also traceable from the muscle belly below the scapular spine Teres minor—posterior and inferior to the supraspinatus, difficult to palpate Subscapularis—inserts anteriorly from the medial side of the humerus onto the lesser tuberosity; external rotation is needed for indirect palpation through overlying muscles ○ Range of motion of the shoulder joint Flexion: anterior deltoid, pec major, coracobrachialis, bicep brachii Extension: lat dorsi, teres major, posterior deltoid, tricep brachii Abduction: supraspinatus, middle deltoid, serratus anterior Adduction: pec major, coracobrachialis, lat dorsi, teres major, subscapularis Internal rotation: subscapularis, anterior deltoid, pec major, teres major, latissimus dorsi External rotation: infraspinatus, teres minor, posterior deltoid, supraspinatus ○ Special maneuvers for examining the shoulder joint Acromioclavicular joint Overall shoulder rotation → Apley scratch test Rotator cuff (pain provocation tests) → painful arc test → fully abduct the patient's arm from 0-180* Neer impingement sign→ press on scapula to prevent scapular motion with one hand and raise the patients arm with the other. This compresses the greater tuberosity of the humerus against the acromion Drop arm test → ask the patient to fully abduct the arm to shoulder level, up to 90* and lower it slowly Abduction above shoulder level from 90-120* reflects action of deltoid muscle Hawkins impingement sign → Flex the patient’s shoulder and elbow to 90* with the palm facing down. Then with one hand on the forearm and one on the arm, rotate the arm internally. This compresses the greater tuberosity against the supraspinatus tendon and coracoacromial ligaments Empty can test → elevate the arms to 90* and internally rotate the arms with the thumbs pointing down, as if emptying a can. Ask the patient to resist as you place downward pressure on the arms The elbow ○ The elbow helps position the hand in space and stabilize the lever action of the forearm ○ T he elbow joint is formed by the humerus and the 2 bones of the forearm, the radius and the ulna ○ Steps to physical exam Inspection Palpation Range of motion Stability Motor Sensory Vascular Provocative tests ○ Inspection Skin Swelling Hypertrophy Atrophy Deformity (compare with contralateral side) ○ Palpation Bony prominences Olecranon Medial epicondyle Lateral epicondye Radial head ○ Best palpated while rotating forearm from pronation to supination Muscles and soft tissues including Flexor-pronator mass Extensor mass origin Olecranon bursa MCL insertion ○ Palpated just distal to medial epicondyle with elbow 50-70* flexion to move flexor-pronator mass anterior LCL insertion Palpate the grooves between the epicondyles and the olecranon process, where the synovium is most easily examined. Normally the synovium and olecranon bursae are not palpable. The sensitive ulnar nerve can be palpated posteriorly between the olecranon process and the medial epicondyle. Feel for warmth in the skin or around the joint that may suggest infection or underlying inflammation. Note any displacement of the olecranon process Range of motion ○ Check passive and active motion of both sides Check for crepitus and mechanical blocks Flexion-extension Normal: 0-140 ○ Loss of full extension can be seen in professional throwers even in absence of pathology Functional: 30-130 ○ Soft end point indicates effusion or capsular tightness ○ Firm end point indicates mechanical block (loose body, fracture, osteophyte) Pronation- supination Check with shoulders fully adducted and elbow at 90% Normal pronation = 75 Normal supination= 85 Functional: 50 pronation and 50 supination Special maneuvers ○ May often complain of pain at or around the bony prominence of the lateral epicondyle that often radiates down the forearm. A number of tests have been described that reproduce this pain along the lateral epicondyle and one such maneuver = Cozen test Stabilize the patient’s elbow and palpate the lateral epicondyle Then ask the patient to pronate and extend the wrist against resistance. Pain should be reproduced along the lateral aspect of the elbow The wrist and hand ○ The wrist and hands form a complex unit of small highly active joints used almost continuously during waking hours. There is little protection from overlying soft tissue, increasing vulnerability to trauma and disability ○ The wrist includes the distal radius and ulna and eight small carpal bones (Fig. 23-28). At the wrist, identify the bony tips of the radius and the ulna. ○ The wrist joints include the radiocarpal or wrist joint, the distal radioulnar joint, and the intercarpal joints (Fig. 23-29). ○ The joint capsule, articular disc, and synovial membrane of the wrist join the radius to the ulna and to the proximal carpal bones. ○ On the dorsum of the wrist, locate the groove of the radiocarpal joint. This joint provides most of the flexion and extension at the wrist because the ulna does not articulate directly with the carpal bones ○ Inspection Skin Discoloration ○ Erythema (cellulitis) ○ White (arterial insufficiency) ○ blue/purple (venous congestion) ○ Black spots (melanoma) Trophic changes (increased hair growth or altered sweat production) ○ Can represent derangement of sympathetic nervous system Scars/wounds Swelling Muscle atrophy Thenar atrophy ○ Median nerve involvement Caused by carpal tunnel syndrome Interossei atrophy ○ Ulnar nerve involvement Caused by cubital tunnel or cervical radiculopath Subcutaneous Atrophy ○ Locally post-steroid injection Deformity (compare with contralateral side) Asymmetry Angulation Rotation Absence of normal anatomy (amputation) Cascade sign ○ Fingers converge toward scaphoid tubercle when flexed at the MCPJ and PIPJ ○ If one or more fingers do not converge, then trauma to the digits has likely altered normal alignment ○ Palpation Masses (ganglions, nodules) Temperature Warm: infection, inflammation Cool: vascular pathology Tenderness Crepitus (fracture) Clicking or snapping (tendonitis) Joint effusion (injection, inflammation, trauma) Palpate the radial styloid bone and the anatomic snuffbox, a hollowed depression just distal to the radial styloid process formed by the abductor and extensor muscles of the thumb The “snuffbox” is more visible with abduction of the thumb. Palpate the carpal bones lying distal to the wrist joint and then each of the metacarpals and the proximal, middle, and distal phalanges Attempt to move the carpal bones relative to each other. There should be little to no movement. Now examine the fingers and thumb. Palpate the medial and lateral aspects of each PIP joint between your thumb and index finger, again checking for swelling, bogginess, bony enlargement, or tenderness. Using the same techniques, examine the DIP joints Bouchard nodes in the PIPs are a classic sign of OA. Heberden nodes, which are more common than Bouchard nodes, are similar bony swellings that develop in the DIPs of patients with OA Neurovascular exam ○ Sensation 2 point discrimination Motor Radial nerve : test thumb IP joint extension against resistance Median nerve ○ Recurrent motor branch: palmar abduction of thumb ○ Anterior interosseous branch: flexion of thumb IP and index DIP (“ a ok sign) Ulnar nerve: cross fingers or abduct fingers against resistance Vascular Radial pulse Ulnar pulse Allen’s test Capillary refill Special manuevers ○ Hand grip strength Ask the patient to grasp your second and third fingers as tightly as possible. This tests the function of wrist joints, the finger flexors, and the intrinsic muscles and joints of the hand. It is always important to determine if weakness is related to pain or true inability to perform the desired Testing for tenosynovitis (finkelstein test) Ask the patient to grasp the thumb against the palm and then move the wrist toward the midline in ulnar deviation Testing for carpal tunnel syndrome Test thetinelsign by repeatedly tapping over thecourse of the medial nerve in the carpal tunnel To test thePhalen sign, ask the patient to hold thewrists in full flexion and juxtaposing the dorsum of each hand against each other for 60 seconds with the elbows fully extended (Fig. 23-51). Alternatively, ask the patient to press the backs of both hands together to form right angles. These maneuvers compress the median nerve.
