APPLIED ANATOMY OF APPLIED ANATOMY OF JOINTSJOINTS

DR IRAM IQBALDR IRAM IQBALPG TRAINEE MPHILLPG TRAINEE MPHILL

UPPER LIMBUPPER LIMB Acromioclavicular Joint Acromioclavicular Joint Sternoclavicular JointSternoclavicular Joint Shoulder JointShoulder Joint ELBOW JOINTELBOW JOINT RADIOULNAR JOINTRADIOULNAR JOINT WRIST JOINTWRIST JOINT INTER CARPAL JOINTINTER CARPAL JOINT CARPOMETECARPAL JOINTCARPOMETECARPAL JOINT METACARPOPHALENGIAL JOINTMETACARPOPHALENGIAL JOINT INTERPHALENGIAL JOINTINTERPHALENGIAL JOINT

Applied anatomy of Applied anatomy of sternoclavicular jointsternoclavicular joint

Ankylosis of Sternoclavicular Ankylosis of Sternoclavicular JointJoint

Movement at the SC joint is critical to Movement at the SC joint is critical to movement of the shoulder. When movement of the shoulder. When ankylosis (stiffening or fixation) of ankylosis (stiffening or fixation) of the joint occurs, or is necessary the joint occurs, or is necessary surgically, a section of the center of surgically, a section of the center of the clavicle is removed, creating a the clavicle is removed, creating a pseudo joint or “flail” joint to permit pseudo joint or “flail” joint to permit scapular movement.scapular movement.

Dislocation of sternoclavicular Dislocation of sternoclavicular jointjoint

The strong costoclavicular ligament firmly The strong costoclavicular ligament firmly

holds the medial end of the clavicle to the holds the medial end of the clavicle to the

first costal cartilage. Violent forces first costal cartilage. Violent forces

directed along the long axis of the clavicle directed along the long axis of the clavicle

usually result in fracture of that bone, but usually result in fracture of that bone, but

dislocation of the sternoclavicular joint dislocation of the sternoclavicular joint

takes place occasionally takes place occasionally

Anterior Anterior dislocationdislocation

results in the results in the

medial end of the medial end of the

clavicle projecting clavicle projecting

forward beneath forward beneath

the skin; it may the skin; it may

also be pulled also be pulled

upward by the upward by the

sternocleidomastoisternocleidomastoi

d muscle. d muscle.

Posterior dislocation of Posterior dislocation of sternoclavicular jointsternoclavicular joint

usually follows direct trauma usually follows direct trauma applied to the front of the applied to the front of the joint that drives the clavicle joint that drives the clavicle backward. This type is the backward. This type is the more serious because the more serious because the displaced clavicle may press displaced clavicle may press on the trachea, the on the trachea, the esophagus, and major blood esophagus, and major blood vessels in the root of the vessels in the root of the neck.neck.

If the costoclavicular If the costoclavicular ligament ruptures ligament ruptures completely, it is difficult to completely, it is difficult to maintain the normal position maintain the normal position of the clavicle once reduction of the clavicle once reduction has been accomplished.has been accomplished.

Acromioclavicular Joint Acromioclavicular Joint injuriesinjuries

The strength of the joint depends on the The strength of the joint depends on the

strong coracoclavicular ligament, which strong coracoclavicular ligament, which

binds the coracoid process to the binds the coracoid process to the

undersurface of the lateral part of the undersurface of the lateral part of the

clavicle.clavicle. The greater part of the weight of the upper The greater part of the weight of the upper

limb is transmitted to the clavicle through limb is transmitted to the clavicle through

this ligament, and rotary movements of the this ligament, and rotary movements of the

scapula occur at this important ligament. scapula occur at this important ligament.

Acromioclavicular DislocationAcromioclavicular Dislocation(shoulder sepration)(shoulder sepration)

A severe blow on the A severe blow on the point of the shoulder, as point of the shoulder, as is,is,

blocking or tackling in blocking or tackling in football football

any severe fall,any severe fall, acromion being thrust acromion being thrust

beneath the lateral end beneath the lateral end of the clavicle, tearing of the clavicle, tearing the coracoclavicular the coracoclavicular ligamen.ligamen.

Glenoid Labrum TearsGlenoid Labrum Tears Tearing of the fibro cartilaginous glenoid labrum Tearing of the fibro cartilaginous glenoid labrum

commonly occurs in athletes who throw a baseball or commonly occurs in athletes who throw a baseball or football and in those who have shoulder instability football and in those who have shoulder instability and subluxation (partial dislocation) of the and subluxation (partial dislocation) of the glenohumeral joint.glenohumeral joint.

The tear often results from sudden contraction of The tear often results from sudden contraction of the biceps or forceful subluxation of the humeral the biceps or forceful subluxation of the humeral head over the glenoid labrum.head over the glenoid labrum.

Usually a tear occurs in the anterosuperior part of Usually a tear occurs in the anterosuperior part of the labrum. the labrum.

The typical symptom is pain while throwing, The typical symptom is pain while throwing, especially during the acceleration phase, but a sense especially during the acceleration phase, but a sense of popping or snapping may be felt in the of popping or snapping may be felt in the glenohumeral joint during abduction and lateral glenohumeral joint during abduction and lateral rotation of the arm.rotation of the arm.

Adhesive Capsulitis of Adhesive Capsulitis of Glenohumeral JointGlenohumeral Joint

Adhesive fibrosis and scarring between the inflamed Adhesive fibrosis and scarring between the inflamed joint capsule of the glenohumeral joint, rotator cuff, joint capsule of the glenohumeral joint, rotator cuff, subacromial bursa, and deltoid usually cause subacromial bursa, and deltoid usually cause (“frozen shoulder”), a condition seen in individuals (“frozen shoulder”), a condition seen in individuals 40-60 years of age.40-60 years of age.

A person with this condition has difficulty abducting A person with this condition has difficulty abducting the arm and can obtain an apparent abduction of up the arm and can obtain an apparent abduction of up to 45° by elevating and rotating the scapula. to 45° by elevating and rotating the scapula.

Because of the lack of movement of the Because of the lack of movement of the glenohumeral joint, strain is placed on the AC joint, glenohumeral joint, strain is placed on the AC joint, which may be painful during other movements which may be painful during other movements (elevation, or shrugging, of the shoulder).(elevation, or shrugging, of the shoulder).

Dislocations of the Shoulder Dislocations of the Shoulder JointJoint

The shoulder joint The shoulder joint is the most is the most commonly commonly dislocated large dislocated large joint joint

Anterior Inferior DislocationAnterior Inferior Dislocation

Sudden violence applied to the Sudden violence applied to the

humerus with the joint fully abducted humerus with the joint fully abducted

tilts the humeral head downward tilts the humeral head downward

onto the inferior weak part of the onto the inferior weak part of the

capsule, which tears, and the capsule, which tears, and the

humeral head comes to lie inferior to humeral head comes to lie inferior to

the glenoid fossa the glenoid fossa

Posterior DislocationsPosterior Dislocations Posterior dislocations are rare and are Posterior dislocations are rare and are

usually caused by direct violence to the usually caused by direct violence to the front of the joint front of the joint

A subglenoid displacement of the head of A subglenoid displacement of the head of the humerus into the quadrangular space the humerus into the quadrangular space can cause damage to the axillary nerve, as can cause damage to the axillary nerve, as indicated by paralysis of the deltoid indicated by paralysis of the deltoid muscle and loss of skin sensation over the muscle and loss of skin sensation over the lower half of the deltoid lower half of the deltoid

Downward displacement of the humerus Downward displacement of the humerus can also stretch and damage the radial can also stretch and damage the radial nervenerve. .

Shoulder PainShoulder Pain

Injury to the shoulder joint is followed by pain, limitation of Injury to the shoulder joint is followed by pain, limitation of

movement, and muscle atrophy owing to disuse.movement, and muscle atrophy owing to disuse.

It is important to appreciate that pain in the shoulder It is important to appreciate that pain in the shoulder

region can be caused by disease elsewhere and that the region can be caused by disease elsewhere and that the

shoulder joint may be normal; for example,shoulder joint may be normal; for example,

diseases of the spinal corddiseases of the spinal cord

and vertebral columnand vertebral column

the pressure of a cervical rib can cause shoulder pain.the pressure of a cervical rib can cause shoulder pain.

Irritation of the diaphragmatic pleura or peritoneum can Irritation of the diaphragmatic pleura or peritoneum can

produce referred pain via the phrenic and supraclavicular produce referred pain via the phrenic and supraclavicular

nerves.nerves.

Bursitis of ElbowBursitis of Elbow The subcutaneous olecranon bursa is exposed to injury The subcutaneous olecranon bursa is exposed to injury

during falls on the elbow and to infection from abrasions of during falls on the elbow and to infection from abrasions of the skin covering the olecranon. Repeated excessive the skin covering the olecranon. Repeated excessive pressure and friction, as occurs in wrestling, pressure and friction, as occurs in wrestling,

for example, may cause this bursa to become inflamed, for example, may cause this bursa to become inflamed, producing a friction (“student's elbow”)producing a friction (“student's elbow”)

This type of bursitis is also known as “dart thrower's This type of bursitis is also known as “dart thrower's elbow” and “miner's elbow.”elbow” and “miner's elbow.”

Occasionally, the bursa becomes infected and the area Occasionally, the bursa becomes infected and the area over the bursa becomes inflamed. is much less common.over the bursa becomes inflamed. is much less common.

It results from excessive friction between the triceps It results from excessive friction between the triceps tendon and olecranon, for example, resulting from repeated tendon and olecranon, for example, resulting from repeated flexion-extension of the forearm as occurs during certain flexion-extension of the forearm as occurs during certain assembly-line jobs. assembly-line jobs.

The pain is most severe during flexion of the forearm The pain is most severe during flexion of the forearm because of pressure exerted on the inflamed subtendinous because of pressure exerted on the inflamed subtendinous olecranon bursa by the triceps tendon results in pain when olecranon bursa by the triceps tendon results in pain when the forearm is pronated because this action compresses the the forearm is pronated because this action compresses the bicipitoradial bursa against the anterior half of the bicipitoradial bursa against the anterior half of the tuberosity of the radius.tuberosity of the radius.

Avulsion of Medial Avulsion of Medial EpicondyleEpicondyle

Avulsion of the medial epicondyle in children can result from a fall Avulsion of the medial epicondyle in children can result from a fall

that causes severe abduction of the extended elbow, an abnormal that causes severe abduction of the extended elbow, an abnormal

movement of this articulation. movement of this articulation.

The resulting traction on the ulnar collateral ligament pulls the The resulting traction on the ulnar collateral ligament pulls the

medial epicondyle distally. medial epicondyle distally.

The anatomical basis of avulsion of the epicondyle is that the The anatomical basis of avulsion of the epicondyle is that the

epiphysis for the medial epicondyle may not fuse with the distal epiphysis for the medial epicondyle may not fuse with the distal

end of the humerus until up to age 20. end of the humerus until up to age 20.

Usually fusion is complete radiographically at age 14 in females Usually fusion is complete radiographically at age 14 in females

and age 16 in males.and age 16 in males.

Stretching of Ulner nerve is a frequent complication of the Stretching of Ulner nerve is a frequent complication of the

abduction type of avulsion of the medial epicondyle. The abduction type of avulsion of the medial epicondyle. The

anatomical basis for this stretching of the ulnar nerve is that it anatomical basis for this stretching of the ulnar nerve is that it

passes posterior to the medial epicondyle before entering the passes posterior to the medial epicondyle before entering the

forearm.forearm.

Subluxation and Dislocation Subluxation and Dislocation of Radial Headof Radial Head

Preschool children, particularly girls, are vulnerable to Preschool children, particularly girls, are vulnerable to transient subluxation (incomplete dislocation) of the head transient subluxation (incomplete dislocation) of the head of the radius (also called “nursemaid's elbow” and “pulled of the radius (also called “nursemaid's elbow” and “pulled elbow”). The history of these cases is typical. The child is elbow”). The history of these cases is typical. The child is suddenly lifted (jerked) by the upper limb while the forearm suddenly lifted (jerked) by the upper limb while the forearm is pronated (is pronated (e.g.e.g., lifting a child) . The child may cry out, , lifting a child) . The child may cry out, refuse to use the limb, and protect the limb by holding it refuse to use the limb, and protect the limb by holding it with the elbow flexed and the forearm pronated.with the elbow flexed and the forearm pronated.

The sudden pulling of the upper limb tears the distal The sudden pulling of the upper limb tears the distal attachment of the anular ligament, where it is loosely attachment of the anular ligament, where it is loosely attached to the neck of the radius. The radial head then attached to the neck of the radius. The radial head then moves distally, partially out of the “socket” formed by the moves distally, partially out of the “socket” formed by the anular ligament . The proximal part of the torn ligament anular ligament . The proximal part of the torn ligament may become trapped between the head of the radius and may become trapped between the head of the radius and the capitulum of the humerus.the capitulum of the humerus.

The source of pain is the pinched anular ligament. The source of pain is the pinched anular ligament. Treatment of the subluxation consists of supination of the Treatment of the subluxation consists of supination of the child's forearm while the elbow is flexed . The tear in the child's forearm while the elbow is flexed . The tear in the anular ligament heals when the limb is placed in a sling for anular ligament heals when the limb is placed in a sling for 2 weeks.2 weeks.

Stability of Elbow JointStability of Elbow Joint

The elbow joint is The elbow joint is stable becausestable because

of the wrench-of the wrench-shaped articular shaped articular surface of the surface of the olecranon and the olecranon and the pulley-shaped pulley-shaped trochlea of the trochlea of the humerus; humerus;

strong medial and strong medial and lateral ligaments. lateral ligaments.

Dislocations of the Elbow Dislocations of the Elbow JointJoint

Elbow dislocations are common, and most Elbow dislocations are common, and most

are posterior. are posterior. Posterior dislocation usually follows falling Posterior dislocation usually follows falling

on the outstretched hand.on the outstretched hand. Posterior dislocations of the joint are Posterior dislocations of the joint are

common in children because the parts of common in children because the parts of

the bones that stabilize the joint are the bones that stabilize the joint are

incompletely developed incompletely developed

Arthrocentesis of the Elbow Arthrocentesis of the Elbow JointJoint

The anterior and posterior walls of the The anterior and posterior walls of the capsule are weak, and when the joint is capsule are weak, and when the joint is distended with fluid, the posterior distended with fluid, the posterior aspect of the joint becomes swollen.aspect of the joint becomes swollen.

Aspiration of joint fluid can easily be Aspiration of joint fluid can easily be performed through the back of the joint performed through the back of the joint on either side of the olecranon process on either side of the olecranon process

Damage to the Ulnar Nerve Damage to the Ulnar Nerve With Elbow Joint InjuriesWith Elbow Joint Injuries

The close relationship of the ulnar nerve to the medial side of The close relationship of the ulnar nerve to the medial side of

the joint often results in its becoming damaged in dislocations the joint often results in its becoming damaged in dislocations

of the joint or in fracture dislocations in this region.of the joint or in fracture dislocations in this region.

The nerve lesion can occur at the time of injury or weeks, The nerve lesion can occur at the time of injury or weeks,

months, or years later. months, or years later.

The nerve can be involved in scar tissue formation The nerve can be involved in scar tissue formation

Ulner nerve can become stretched owing to lateral deviation of Ulner nerve can become stretched owing to lateral deviation of

the forearm in a badly reduced supracondylar fracture of the the forearm in a badly reduced supracondylar fracture of the

humerus.humerus.

During movements of the elbow joint, the continued friction During movements of the elbow joint, the continued friction

between the medial epicondyle and the stretched ulnar nerve between the medial epicondyle and the stretched ulnar nerve

eventually results in ulnar palsy.eventually results in ulnar palsy.

Radioulnar Joint DiseaseRadioulnar Joint Disease

The proximal radioulnar joint The proximal radioulnar joint

communicates with the elbow jointcommunicates with the elbow joint

distal radioulnar joint does not distal radioulnar joint does not

communicate with the wrist joint.communicate with the wrist joint.

this means that infection of the elbow joint this means that infection of the elbow joint

invariably involves the proximal radioulnar invariably involves the proximal radioulnar

joint. joint.

Rheumatoid arthritisRheumatoid arthritis It commonly affects the wrist and hands and is a It commonly affects the wrist and hands and is a

major cause of serious loss of function and ugly major cause of serious loss of function and ugly

deformities.deformities.

Affected joints are swollen from synovial Affected joints are swollen from synovial

thickening and movement is restricted.thickening and movement is restricted.

In the later stages articular cartilage and the In the later stages articular cartilage and the

underlying bones are eroded and the fingers tend underlying bones are eroded and the fingers tend

to deviate medially – ulnar deviation.to deviate medially – ulnar deviation.

Rheumatoid arthritisRheumatoid arthritis

The strength of the proximal The strength of the proximal radioulnar joint depends on the radioulnar joint depends on the integrity of the strong anular integrity of the strong anular ligament.ligament.

Rupture of this ligament occurs in Rupture of this ligament occurs in cases of anterior dislocation of the cases of anterior dislocation of the head of the radius on the capitulum of head of the radius on the capitulum of the humerus. the humerus.

In young children, in whom the head In young children, in whom the head of the radius is still small and of the radius is still small and undeveloped, a sudden jerk on the undeveloped, a sudden jerk on the arm can pull the radial head down arm can pull the radial head down through the anular ligament. through the anular ligament.

Wrist Joint InjuriesWrist Joint Injuries

A fall on the outstretched hand can A fall on the outstretched hand can strain the anterior ligament of the strain the anterior ligament of the wrist joint, wrist joint,

producing synovial effusion, joint producing synovial effusion, joint pain, and limitation of movement. pain, and limitation of movement.

These symptoms and signs must not These symptoms and signs must not be confused with those produced by be confused with those produced by a fractured scaphoid or dislocation of a fractured scaphoid or dislocation of the lunate bone.the lunate bone.

Madelung’s deformityMadelung’s deformity It is the congenital subluxation or dislocation of lower end It is the congenital subluxation or dislocation of lower end

of ulna from malformation of the bones. of ulna from malformation of the bones. There may be minor generalised abnormalities of bone There may be minor generalised abnormalities of bone

structure often with short stature. structure often with short stature. It may be also be caused by disease or fracture – a fracture It may be also be caused by disease or fracture – a fracture

at the lower end of the radius with upward displacement of at the lower end of the radius with upward displacement of the lower fragment.the lower fragment.

The deformity varies in degree from a slight prominence of The deformity varies in degree from a slight prominence of lower end of ulna at the back of the wrist to complete lower end of ulna at the back of the wrist to complete dislocation of the inferior radio- ulnar joint with marked dislocation of the inferior radio- ulnar joint with marked radial deviation of the hand.radial deviation of the hand.

The more sever form is associated with congenital absence The more sever form is associated with congenital absence of the radius of the radius

Bull Rider's ThumbBull Rider's Thumb refers to a sprain of refers to a sprain of the radial collateral ligament and an the radial collateral ligament and an avulsion fracture of the lateral part of the avulsion fracture of the lateral part of the proximal phalanx of the thumb. This injury is proximal phalanx of the thumb. This injury is common in individuals who ride mechanical common in individuals who ride mechanical bulls.bulls.

Skier's ThumbSkier's Thumb Skier's thumb (historically, game-keeper's Skier's thumb (historically, game-keeper's

thumb) refers to the rupture or chronic thumb) refers to the rupture or chronic laxity of the collateral ligament of the 1st MP laxity of the collateral ligament of the 1st MP joint . The injury results from joint . The injury results from hyperabduction of the MP joint of the thumb, hyperabduction of the MP joint of the thumb, which occurs when the thumb is held by the which occurs when the thumb is held by the ski pole while the rest of the hand hits the ski pole while the rest of the hand hits the ground or enters the snow. In severe ground or enters the snow. In severe injuries, the head of the metacarpal has an injuries, the head of the metacarpal has an avulsion fracture.avulsion fracture.

Falls on the Outstretched Falls on the Outstretched Hand Hand

In falls on the outstretched hand, forces In falls on the outstretched hand, forces are transmitted from the scaphoidare transmitted from the scaphoid

to the distal end of the radius,to the distal end of the radius, from the radius across the interosseous from the radius across the interosseous

membrane to the ulna,membrane to the ulna, and from the ulna to the humerus;and from the ulna to the humerus; through the glenoid fossa of the scapula through the glenoid fossa of the scapula

to the coracoclavicular ligament and the to the coracoclavicular ligament and the clavicle; clavicle;

and finally, to the sternum.and finally, to the sternum.

Falls on the Outstretched Falls on the Outstretched HandHand

If the forces are excessive, different parts of If the forces are excessive, different parts of the upper limb give way under the strain.the upper limb give way under the strain.

The area affected seems to be related to The area affected seems to be related to age. In a young child, for example, there may age. In a young child, for example, there may be a posterior displacement of the distal be a posterior displacement of the distal radial epiphysis;radial epiphysis;

in the teenager the clavicle might fracture;in the teenager the clavicle might fracture; in the young adult the scaphoid is commonly in the young adult the scaphoid is commonly

fractured; and fractured; and in the elderly the distal end of the radius is in the elderly the distal end of the radius is

fractured about 1 in. (2.5 cm) proximal to the fractured about 1 in. (2.5 cm) proximal to the wrist joint (Colles' fracture)wrist joint (Colles' fracture)

Applied anatomy of Joints of Applied anatomy of Joints of Lower LimbLower Limb

Hip JointHip Joint Knee JointKnee Joint Tibiofibular JointsTibiofibular Joints Ankle JointAnkle Joint Joints of FootJoints of Foot

Applied anatomy of Hip jointApplied anatomy of Hip joint

Dislocation of hip jointDislocation of hip joint

It can be of two typesIt can be of two types 1 Congenital dislocation 1 Congenital dislocation 2 Acquired dislocation 2 Acquired dislocation

According to the direction of According to the direction of dislocationdislocation

1 Posterior dislocation - Commonest1 Posterior dislocation - Commonest2 Anterior dislocation2 Anterior dislocation3 Central dislocation 3 Central dislocation

Dislocation of Hip JointDislocation of Hip Joint acquired dislocation of hip acquired dislocation of hip

jointjoint– UncommonUncommon– dislocation may occur dislocation may occur

during an automobile during an automobile accident when the hip is accident when the hip is flexed, adducted, and flexed, adducted, and medially rotated, the usual medially rotated, the usual position of the lower limb position of the lower limb when a person is riding in when a person is riding in a car.a car.

– Posterior dislocations are Posterior dislocations are most common. most common.

– The fibrous layer of the The fibrous layer of the joint capsule ruptures joint capsule ruptures inferiorly and posteriorly, inferiorly and posteriorly, allowing the femoral head allowing the femoral head to pass through the tear in to pass through the tear in the capsule and over the the capsule and over the posterior margin of the posterior margin of the acetabulum onto the acetabulum onto the lateral surface of the ilium, lateral surface of the ilium,

– shortening and medially shortening and medially rotating the affected limbrotating the affected limb

congenital dislocation of congenital dislocation of hip jointhip joint– commoncommon

it affects more girlsit affects more girls– bilateral in approximately bilateral in approximately

half the cases.half the cases.– Dislocation occurs when Dislocation occurs when

the femoral head is not the femoral head is not properly located in the properly located in the acetabulum.acetabulum.

– The affected limb appears The affected limb appears (and functions as if) (and functions as if) shorter because the shorter because the dislocated femoral head is dislocated femoral head is more superior than on the more superior than on the normal side, resulting in a normal side, resulting in a positive (hip appears to positive (hip appears to drop to one side during drop to one side during walking).walking).

– Inability to abduct the Inability to abduct the thigh is characteristic of thigh is characteristic of congenital dislocation congenital dislocation

Congenital dislocation of hip Congenital dislocation of hip jointjoint

AQUIRED DISLOCATIONAQUIRED DISLOCATION

Dislocation occurring after the 1st Dislocation occurring after the 1st year of life is usually due to one of year of life is usually due to one of the 3 cause -the 3 cause --Pyogenic arthritis.-Pyogenic arthritis.-Muscle imbalance -Muscle imbalance -Trauma-TraumaRare causes areRare causes are-Tuberculosis -Tuberculosis -Charcot’s disease.-Charcot’s disease.

Poster dislocation Anterior Poster dislocation Anterior dislocationdislocation

Posterior dislocationPosterior dislocation Most common verity. Most common verity. usually occurs in a road usually occurs in a road

accident, when someone is accident, when someone is seated in a trunk or car is seated in a trunk or car is thrown forward & striking thrown forward & striking against the dashboard. against the dashboard.

Here the femur is thrust Here the femur is thrust upwards and femoral head upwards and femoral head is forced out of it’s socket.is forced out of it’s socket.

Here the leg is short and Here the leg is short and lies adducted, internally lies adducted, internally rotated and slightly flexed.rotated and slightly flexed.

the capsule ruptures the capsule ruptures inferiorly and posteriorly inferiorly and posteriorly allowing the femoral head allowing the femoral head to pass through the tear in to pass through the tear in the capsule and over the the capsule and over the posterior margin of the posterior margin of the acetabulum.acetabulum.

..

ANTERIOR DISLOCATIONANTERIOR DISLOCATION Rare Usual cause is a Rare Usual cause is a

road accident or air crash road accident or air crash .Dislocation of one or .Dislocation of one or

even both hips may occur even both hips may occur when a weight falls on to when a weight falls on to the back of a person , the back of a person , with his legs wide apart , with his legs wide apart , knees straight and back knees straight and back bent forwards.bent forwards.

Here the leg lies Here the leg lies externally rotated , externally rotated , abducted and slightly abducted and slightly flexed. flexed.

It is not short because the It is not short because the attachment of rectus attachment of rectus femoris prevent the head femoris prevent the head from dislocation upwards. from dislocation upwards. The prominent head is The prominent head is easy to feel.easy to feel.

CENTRAL DISLOCATIONCENTRAL DISLOCATION A fall on the side or a blow over the greater A fall on the side or a blow over the greater

trochanter may thrust the femoral head into trochanter may thrust the femoral head into

the floor of the acetabulum and fracture of the the floor of the acetabulum and fracture of the

plevis.plevis. In this case trochanter and hip region are In this case trochanter and hip region are

tender. Little movements are possible.tender. Little movements are possible.

On X-ray The femoral head is displaced On X-ray The femoral head is displaced medically and the acetabular floor is medically and the acetabular floor is fracturedfractured..

. . Tuberculosis of hipTuberculosis of hip The hip is one of the joints most frequently affected by The hip is one of the joints most frequently affected by

tuberculosis. The patient may have a history of active tuberculosis. The patient may have a history of active pulmonary tuberculosis.pulmonary tuberculosis.

Acute Suppurative arthritisAcute Suppurative arthritisThis condition is more common in children. It is often This condition is more common in children. It is often

secondary to osteomyelitis of the upper end of femur.secondary to osteomyelitis of the upper end of femur.Rheumatoid arthritisRheumatoid arthritis

Hip joint is not affected usually in case of RA. But when they Hip joint is not affected usually in case of RA. But when they are affected the consequent disability is serious.are affected the consequent disability is serious.

OsteoarthritisOsteoarthritisIt is a common cause of severe disablement especially in It is a common cause of severe disablement especially in elderly. It also affect young persons, when there has been elderly. It also affect young persons, when there has been previous damage from injury or disease.previous damage from injury or disease.

The irritable hipThe irritable hipTransient hip pain and restriction of movement in an Transient hip pain and restriction of movement in an otherwise healthy child. It is the commonest cause of hip otherwise healthy child. It is the commonest cause of hip pain in children. Boys are commonly affected. (age group -pain in children. Boys are commonly affected. (age group -6-12 yrs of age) Presents with pain and a limp often 6-12 yrs of age) Presents with pain and a limp often intermittent & following activity and extremes of all intermittent & following activity and extremes of all movements are limitedmovements are limited

OVERVIEW OF LIGAMENTSOVERVIEW OF LIGAMENTS

Knee Joint InjuriesKnee Joint Injuries Hyperextension and severe force directed anteriorly against the femur with the knee Hyperextension and severe force directed anteriorly against the femur with the knee

semiflexed (a cross-body block in football) may tear the ACL. semiflexed (a cross-body block in football) may tear the ACL. ACL rupturesACL ruptures are also are also

common knee injuries in skiing accidents. This injury causes the free tibia to slide common knee injuries in skiing accidents. This injury causes the free tibia to slide

anteriorly under the fixed femur, known as anteriorly under the fixed femur, known as anterior drawer signanterior drawer sign , tested clinically via , tested clinically via

the the lachman testlachman test The ACL may tear away from the femur or tibia; however, tears The ACL may tear away from the femur or tibia; however, tears

commonly occur in the midportion of the ligament.commonly occur in the midportion of the ligament.

Although strong, Although strong, PCL rupturesPCL ruptures may occur when a player lands on the tibial may occur when a player lands on the tibial

tuberosity with the knee flexed ( when knocked to the floor in basketball). PCL tuberosity with the knee flexed ( when knocked to the floor in basketball). PCL

ruptures usually occur in conjunction with tibial or fibular ligament tears. These ruptures usually occur in conjunction with tibial or fibular ligament tears. These

injuries can also occur in head-on collisions when seat belts are not worn and the injuries can also occur in head-on collisions when seat belts are not worn and the

proximal end of the tibia strikes the dashboard. PCL ruptures allow the free tibia to proximal end of the tibia strikes the dashboard. PCL ruptures allow the free tibia to

slide posteriorly under the fixed femur ,known as the slide posteriorly under the fixed femur ,known as the posterior drawer sign posterior drawer sign

ANTERIOR CRUCIATE ANTERIOR CRUCIATE LIGAMENT INJURYLIGAMENT INJURY

OVERVIEW OF INJURYOVERVIEW OF INJURY

POSTERIOR CRUCIATE POSTERIOR CRUCIATE LIGAMENTLIGAMENT

ILLUSTRATIONILLUSTRATION

Meniscal tearsMeniscal tears Meniscal tearsMeniscal tears usually involve the medial meniscus. The usually involve the medial meniscus. The

lateral meniscus does not usually tear because of its lateral meniscus does not usually tear because of its mobility.mobility.

Pain on lateral rotation of the tibia on the femur indicates Pain on lateral rotation of the tibia on the femur indicates injury of the lateral meniscus , whereas pain on medial injury of the lateral meniscus , whereas pain on medial rotation of the tibia on the femur indicates injury of the rotation of the tibia on the femur indicates injury of the medial meniscus medial meniscus

Most meniscal tears occur in conjunction with TCL or ACL Most meniscal tears occur in conjunction with TCL or ACL tears. Peripheral meniscal tears can often be repaired or tears. Peripheral meniscal tears can often be repaired or may heal on their own because of the generous blood may heal on their own because of the generous blood supply to this area. Meniscal tears that do not heal or supply to this area. Meniscal tears that do not heal or cannot be repaired are usually removed (cannot be repaired are usually removed (e.g.e.g., by , by arthroscopic surgery).arthroscopic surgery).

Knee joints from which the menisci have been removed Knee joints from which the menisci have been removed suffer no loss of mobility; however, the knee may be less suffer no loss of mobility; however, the knee may be less stable and the tibial plateaus often undergo inflammatory stable and the tibial plateaus often undergo inflammatory reactions.reactions.

oVERVIEW OF MENISCI

MENISCUS DEGENERATIONMENISCUS DEGENERATION

BUCKET HANDLE TEARBUCKET HANDLE TEAR

LATERAL MENISCUS INJURYLATERAL MENISCUS INJURY

OVERVIEW OF COLLATERAL OVERVIEW OF COLLATERAL LIGAMENTSLIGAMENTS

ligament sprainsligament sprains The most common knee injuries in contact The most common knee injuries in contact

sports are sports are ligament sprainsligament sprains , which occur , which occur when the foot is fixed in the ground . If a when the foot is fixed in the ground . If a force is applied against the knee when the force is applied against the knee when the foot cannot move, ligament injuries are foot cannot move, ligament injuries are likely to occur. The tibial and fibular likely to occur. The tibial and fibular collateral ligaments (TCL and FCL) are collateral ligaments (TCL and FCL) are tightly stretched when the leg is extended, tightly stretched when the leg is extended, normally preventing disruption of the sides normally preventing disruption of the sides of the knee joint.of the knee joint.

The firm attachment of the TCL to the The firm attachment of the TCL to the medial meniscus is of considerable clinical medial meniscus is of considerable clinical significance because tearing of this significance because tearing of this ligament frequently results in concomitant ligament frequently results in concomitant tearing of the medial meniscus. tearing of the medial meniscus.

““unhappy triadunhappy triad The injury is frequently caused by a blow to the The injury is frequently caused by a blow to the

lateral side of the extended knee or excessive lateral side of the extended knee or excessive lateral twisting of the flexed knee that disrupts lateral twisting of the flexed knee that disrupts the TCL and concomitantly tears and/or detaches the TCL and concomitantly tears and/or detaches the medial meniscus from the joint capsule. This the medial meniscus from the joint capsule. This injury is common in athletes who twist their injury is common in athletes who twist their flexed knees while running in basketball, the flexed knees while running in basketball, the various forms of football, and volleyball). The various forms of football, and volleyball). The ACL, which serves as a pivot for rotatory ACL, which serves as a pivot for rotatory movements of the knee and is taut during flexion, movements of the knee and is taut during flexion, may also tear subsequent to the rupture of the may also tear subsequent to the rupture of the TCL, creating an TCL, creating an “unhappy triad”“unhappy triad” of knee injuries. of knee injuries.

Coxa Vara and Coxa ValgaCoxa Vara and Coxa Valga

The angle of inclination varies with age, The angle of inclination varies with age, sex, and development of the femur (e.g., sex, and development of the femur (e.g., consequent to a congenital defect in consequent to a congenital defect in ossification of the femoral neck). It also ossification of the femoral neck). It also may change with any pathological process may change with any pathological process that weakens the neck of the femur (e.g., that weakens the neck of the femur (e.g., rickets). When the angle of inclination is rickets). When the angle of inclination is decreased, the condition is decreased, the condition is Coxa varaCoxa vara, , when it is increased, the condition is . when it is increased, the condition is . Coxa valgaCoxa valga causes a mild passive causes a mild passive abduction of the hip.abduction of the hip.

Coxa Vara and Coxa ValgaCoxa Vara and Coxa Valga

Patellar DislocationPatellar Dislocation

When the patella is dislocated, it nearly always dislocates When the patella is dislocated, it nearly always dislocates laterally. Patellar dislocation is more common in women, laterally. Patellar dislocation is more common in women, presumably because of their greater P.662presumably because of their greater P.662

Q-angle, which, in addition to representing the oblique placement Q-angle, which, in addition to representing the oblique placement of the femur relative to the tibia, represents the angle of pull of of the femur relative to the tibia, represents the angle of pull of the quadriceps relative to the axis of the patella and tibia (the the quadriceps relative to the axis of the patella and tibia (the term term Q-angleQ-angle was actually coined in reference to the angle of pull was actually coined in reference to the angle of pull of the quadriceps). The tendency toward lateral dislocation is of the quadriceps). The tendency toward lateral dislocation is normally counterbalanced by the medial, more horizontal pull of normally counterbalanced by the medial, more horizontal pull of the powerful vastus medialis. In addition, the more anterior the powerful vastus medialis. In addition, the more anterior projection of the lateral femoral condyle and deeper slope for the projection of the lateral femoral condyle and deeper slope for the larger lateral patellar facet provide a mechanical deterrent to larger lateral patellar facet provide a mechanical deterrent to lateral dislocation. An imbalance of the lateral pull and the lateral dislocation. An imbalance of the lateral pull and the mechanisms resisting it result in abnormal tracking of the patella mechanisms resisting it result in abnormal tracking of the patella within the patellar groove and chronic patellar pain, even if actual within the patellar groove and chronic patellar pain, even if actual dislocation does not occurdislocation does not occur

Bursitis in the Knee RegionBursitis in the Knee Region Prepatellar brusitisPrepatellar brusitis is usually a friction bursitis caused by is usually a friction bursitis caused by

friction between the skin and the patella. friction between the skin and the patella. If the inflammation is chronic, the bursa becomes distended If the inflammation is chronic, the bursa becomes distended

with fluid and forms a swelling anterior to the knee results with fluid and forms a swelling anterior to the knee results from excessive friction between the skin and the tibial from excessive friction between the skin and the tibial tuberosity; the edema occurs over the proximal end of the tuberosity; the edema occurs over the proximal end of the tibia. results in edema between the patellar ligament and tibia. results in edema between the patellar ligament and the tibia, superior to the tibial tuberosity.the tibia, superior to the tibial tuberosity.

The suprapatellar bursa communicates with the articular The suprapatellar bursa communicates with the articular cavity of the knee joint; consequently, abrasions or cavity of the knee joint; consequently, abrasions or penetrating wounds (e.g., a stab wound) superior to the penetrating wounds (e.g., a stab wound) superior to the patella may result in caused by bacteria entering the bursa patella may result in caused by bacteria entering the bursa from the torn skin. The infection may spread to the knee from the torn skin. The infection may spread to the knee joint.joint.

Popliteal CystsPopliteal Cysts Popliteal CystsPopliteal Cysts (Baker cysts) are abnormal fluid (Baker cysts) are abnormal fluid

filled sacs of synovial membrane in the region of filled sacs of synovial membrane in the region of the popliteal fossa. A popliteal cyst is almost the popliteal fossa. A popliteal cyst is almost always a complication of chronic knee joint always a complication of chronic knee joint effusion. The cyst may be a herniation of the effusion. The cyst may be a herniation of the gastrocnemius or semimembranosus bursa gastrocnemius or semimembranosus bursa through the fibrous layer of the joint capsule into through the fibrous layer of the joint capsule into the popliteal fossa, communicating with the the popliteal fossa, communicating with the synovial cavity of the knee joint by a narrow stalk synovial cavity of the knee joint by a narrow stalk . Synovial fluid may also escape from the knee . Synovial fluid may also escape from the knee joint joint synovial effusionsynovial effusion or a bursa around the knee or a bursa around the knee and collect in the popliteal fossa. Here it forms a and collect in the popliteal fossa. Here it forms a new synovial-lined sac, or popliteal cyst. Popliteal new synovial-lined sac, or popliteal cyst. Popliteal cysts are common in children but seldom cause cysts are common in children but seldom cause symptoms. In adults, popliteal cysts can be large, symptoms. In adults, popliteal cysts can be large, extending as far as the midcalf, and may interfere extending as far as the midcalf, and may interfere with knee movements.with knee movements.

The ankle is the most The ankle is the most frequently injured major joint frequently injured major joint in the body. in the body. Ankle sprainsAnkle sprains (torn fibers of ligaments) are (torn fibers of ligaments) are most common. A sprained most common. A sprained ankle is nearly always ankle is nearly always an an inversioninversion injury , involving injury , involving twisting of the weight-twisting of the weight-bearing plantarflexed foot. bearing plantarflexed foot. The person steps on an The person steps on an uneven surface and the foot uneven surface and the foot is forcibly inverted is forcibly inverted Lateral Lateral ligament sprains .ligament sprains . occur in sports in which occur in sports in which running and jumping are running and jumping are common, particularly common, particularly basketball basketball

Ankle InjuriesAnkle Injuries

The lateral ligament is injured because it is The lateral ligament is injured because it is much weaker than the medial ligament and much weaker than the medial ligament and is the ligament that resists inversion at the is the ligament that resists inversion at the talocrural joint. The talocrural joint. The anterior talofibularanterior talofibular ligamentligament —part of the lateral ligament—is —part of the lateral ligament—is most vulnerable and most commonly torn most vulnerable and most commonly torn during ankle sprains, either partially or during ankle sprains, either partially or completely, resulting in instability of the completely, resulting in instability of the ankle joint . The ankle joint . The calcaneofibular ligamentcalcaneofibular ligament may also be torn. In severe sprains, the may also be torn. In severe sprains, the lateral malleolus of the fibula may be lateral malleolus of the fibula may be fractured. Shearing injuries fracture the fractured. Shearing injuries fracture the lateral malleolus at or superior to the ankle lateral malleolus at or superior to the ankle joint. Avulsion fractures break the joint. Avulsion fractures break the malleolus inferior to the ankle joint; a malleolus inferior to the ankle joint; a fragment of bone is pulled off by the fragment of bone is pulled off by the attached ligaments).attached ligaments).

A occurs when the foot is forcibly everted . A occurs when the foot is forcibly everted . This action pulls on the extremely strong This action pulls on the extremely strong medial ligament, often tearing off the medial ligament, often tearing off the medial malleolus. The talus then moves medial malleolus. The talus then moves laterally, shearing off the lateral malleolus laterally, shearing off the lateral malleolus or, more commonly, breaking the fibula or, more commonly, breaking the fibula superior to the tibiofibular syndesmosis. If superior to the tibiofibular syndesmosis. If the tibia is carried anteriorly, the posterior the tibia is carried anteriorly, the posterior margin of the distal end of the tibia is also margin of the distal end of the tibia is also sheared off by the talus, producing a sheared off by the talus, producing a “trimalleolar fracture.” In applying this “trimalleolar fracture.” In applying this term to this injury, the entire distal end of term to this injury, the entire distal end of the tibia is erroneously considered to be a the tibia is erroneously considered to be a “malleolus.”“malleolus.”

Pott fracture, dislocation of Pott fracture, dislocation of ankle jointankle joint

A A Pott fracture-Pott fracture-dislocation of the ankledislocation of the ankle occurs when the foot is occurs when the foot is forcibly averted. forcibly averted.

This action pulls on the This action pulls on the extremely strong medial extremely strong medial ligament, often tearing off the ligament, often tearing off the medial malleolus.medial malleolus.

The talus then moves laterally, The talus then moves laterally, shearing off the lateral shearing off the lateral malleolus or, more commonly, malleolus or, more commonly, breaking the fibula superior to breaking the fibula superior to the tibiofibular syndesmosis.the tibiofibular syndesmosis.

If the tibia is carried If the tibia is carried anteriorly, the posterior margin anteriorly, the posterior margin of the distal end of the tibia is of the distal end of the tibia is also sheared off by the talus. also sheared off by the talus.

Pes Planus (FlatfeetPes Planus (Flatfeet))

The flat appearance of the foot before age 3 is The flat appearance of the foot before age 3 is normal and results from the thick subcutaneous normal and results from the thick subcutaneous fat pad in the sole.fat pad in the sole.

As children get older, the fat is lost, and a normal As children get older, the fat is lost, and a normal medial longitudinal arch becomes visible . medial longitudinal arch becomes visible . Flatfeet can either beFlatfeet can either be flexibleflexible ( ( (flat, lacking a (flat, lacking a medial arch, when weight-bearing but normal in medial arch, when weight-bearing but normal in appearance when not bearing weight or appearance when not bearing weight or rigid rigid (flat (flat even when not bearing weight). even when not bearing weight).

The more common The more common flexible flatfeetflexible flatfeet result from loose result from loose or degenerated intrinsic ligaments (inadequate or degenerated intrinsic ligaments (inadequate passive arch support). passive arch support).

Flexible flatfoot is common in childhood but Flexible flatfoot is common in childhood but usually resolves with age as the ligaments grow usually resolves with age as the ligaments grow and mature. and mature.

The condition occasionally persists into The condition occasionally persists into adulthood and may or may not be adulthood and may or may not be symptomatic. symptomatic. with with Rigid flatfeetRigid flatfeet a history a history that goes back to childhood are likely to that goes back to childhood are likely to result from a bone deformity (such as a result from a bone deformity (such as a fusion of adjacent tarsal bones).fusion of adjacent tarsal bones). Rigid Rigid flatfeetflatfeet (“fallen arches”) are likely to be (“fallen arches”) are likely to be secondary to dysfunction of the tibialis secondary to dysfunction of the tibialis posterior (dynamic arch support) owing to posterior (dynamic arch support) owing to trauma, degeneration with age, or trauma, degeneration with age, or denervation.denervation.

In the absence of normal passive or In the absence of normal passive or dynamic support, the plantar dynamic support, the plantar calcaneonavicular ligament fails to support calcaneonavicular ligament fails to support the head of the talus. Consequently, the the head of the talus. Consequently, the head of the talus displaces inferomedially head of the talus displaces inferomedially and becomes prominent . As a result, and becomes prominent . As a result, some flattening of the some flattening of the

medial part of the longitudinal arch medial part of the longitudinal arch

occurs, along with lateral deviation of occurs, along with lateral deviation of

the forefoot. the forefoot.

Flatfeet are common in older people, Flatfeet are common in older people,

particularly if they undertake much particularly if they undertake much

unaccustomed standing or gain unaccustomed standing or gain

weight rapidly, adding stress on the weight rapidly, adding stress on the

muscles and increasing the strain on muscles and increasing the strain on

the ligaments supporting the arches.the ligaments supporting the arches.

Claw ToesClaw Toes are characterized by are characterized by hyperextension of the hyperextension of the metatarsophalangeal joints and flexion of metatarsophalangeal joints and flexion of the distal interphalangeal joints.the distal interphalangeal joints.

Usually, the lateral four toes are involved. Usually, the lateral four toes are involved. Callosities develop on the dorsal surfaces Callosities develop on the dorsal surfaces of the toes because of pressure of the of the toes because of pressure of the shoe. shoe.

They may also form on the plantar They may also form on the plantar surfaces of the metatarsal heads and the surfaces of the metatarsal heads and the toe tips because they bear extra weight toe tips because they bear extra weight when claw toes are present.when claw toes are present.

Claw ToesClaw Toes

) ) Clubfoot (Talipes Clubfoot (Talipes equinovarusequinovarus

Clubfoot (Talipes equinovarus)Clubfoot (Talipes equinovarus) refers to a foot that is refers to a foot that is twisted out of position. Of the several types, all are twisted out of position. Of the several types, all are congenital (presentcongenital (present at birth). Talipes equinovarusat birth). Talipes equinovarus, , (present at birth). , the common type (2 per 1000 live (present at birth). , the common type (2 per 1000 live births), involves the subtalar joint; boys are affected twice births), involves the subtalar joint; boys are affected twice as often as girls. as often as girls.

The foot is inverted, the ankle is plantar flexed, and the The foot is inverted, the ankle is plantar flexed, and the forefoot is adducted (turned toward the midline in an forefoot is adducted (turned toward the midline in an abnormal manner) . abnormal manner) .

The foot assumes the position of a horse's hoof, hence the The foot assumes the position of a horse's hoof, hence the prefix “equino” (equinus horse). In half of those affected, prefix “equino” (equinus horse). In half of those affected, both feet are malformed.both feet are malformed.

A person with an uncorrected clubfoot cannot put the heel A person with an uncorrected clubfoot cannot put the heel and sole flat and must bear the weight on the lateral and sole flat and must bear the weight on the lateral surface of the forefoot. surface of the forefoot.

Consequently, walking is painful. The main abnormality is Consequently, walking is painful. The main abnormality is shortness and tightness of the muscles, tendons, ligaments, shortness and tightness of the muscles, tendons, ligaments, and joint capsules on the medial side and posterior aspect and joint capsules on the medial side and posterior aspect of the foot and ankle.of the foot and ankle.

Hammer ToeHammer Toe Hammer ToeHammer Toe is a foot deformity in which the proximal is a foot deformity in which the proximal

phalanx is permanently and markedly dorsiflexed phalanx is permanently and markedly dorsiflexed (hyperextended) at the metatarsophalangeal joint and the (hyperextended) at the metatarsophalangeal joint and the middle phalanx strongly plantar flexed at the proximal middle phalanx strongly plantar flexed at the proximal interphalangeal joint.interphalangeal joint.

The distal phalanx of the digit is often also hyperextended. The distal phalanx of the digit is often also hyperextended. This gives the digit (usually the 2nd) a hammer-like This gives the digit (usually the 2nd) a hammer-like appearance. appearance.

This deformity of one or more toes may result from This deformity of one or more toes may result from weakness of the lumbrical and interosseous muscles, which weakness of the lumbrical and interosseous muscles, which flex the metatarsophalangeal joints and extend the flex the metatarsophalangeal joints and extend the interphalangeal joints.interphalangeal joints.

A A callosity or calluscallosity or callus , hard thickening of the keratin layer , hard thickening of the keratin layer of the skin, often develops where the dorsal surface of the of the skin, often develops where the dorsal surface of the toe repeatedly rubs on the shoe.toe repeatedly rubs on the shoe.

Hallux ValgusHallux Valgus Hallux valgus Hallux valgus is a foot deformity caused by pressure is a foot deformity caused by pressure

from footwear and degenerative joint disease;from footwear and degenerative joint disease; it is characterized by lateral deviation of the great toe .it is characterized by lateral deviation of the great toe . The in valgus indicates In some people, the painful The in valgus indicates In some people, the painful

deviation is so large that the great toe overlaps the 2nd toe deviation is so large that the great toe overlaps the 2nd toe , and there is a decrease in the medial longitudinal arch. , and there is a decrease in the medial longitudinal arch.

Such deviation occurs especially in females, and its Such deviation occurs especially in females, and its frequency increases with age.frequency increases with age.

These individuals cannot move their 1st digit away from These individuals cannot move their 1st digit away from their 2nd digit because the sesamoids under the head of their 2nd digit because the sesamoids under the head of the 1st metatarsal are usually displaced and lie in the space the 1st metatarsal are usually displaced and lie in the space between the heads of the 1st and 2nd metatarsals. The 1st between the heads of the 1st and 2nd metatarsals. The 1st metatarsal shifts medially and the sesamoids shift laterally. metatarsal shifts medially and the sesamoids shift laterally.

Often the surrounding tissues swell and the resultant Often the surrounding tissues swell and the resultant pressure and friction against the shoe cause a pressure and friction against the shoe cause a subcutaneous bursa to form; when tender and inflamed.subcutaneous bursa to form; when tender and inflamed.