Anatomy - Lower Limb

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Clinical Correlations

Avulsion or rupture of Achilles Tendon

Disables the triceps surae muscles, pt is unable to plantarflex the foot.

Achilles Reflex

(Ankle jerk) reflex twitch of the triceps surae induced by tapping the tendo calcaneus. Causes plantar flexion of the foot and tests its reflex center in the L5-S1 or S1-S2 segments of the spinal cord. Both afferent and efferent limbs of the reflex are carried in the tibial nerve.

Anterior Tibial Compartment Syndrome

Characterized by ischemic necrosis of the muscules of the anterior compartment of the leg. Occurs as a result of compression of arteries by swollen muscles following excessive exertion. Accompanied by extreme tenderness and pain on anterolateral aspect of leg.

Adductor Longus Strain

May occur in horseback riders and produce pain because the riders adduct their thighs to keep from falling off the animals.

Anterior Drawer Sign

forward sliding of the tibia on the femur due to a rupture of the anterior cruciate ligament.

Replaced or Accessory Obturator Artery

Enlarged pubic branch of inferior epigastric artery either takes the place of obturator artery or joins it as an accessory obturator artery in aprox 20% of people. Artery runs close to or across the femoral ring to reach the obturator foramen and could be closely related to the neck of a femoral hernia. Artery could be involved in strangulation. Surgeons placing staples during endoscopic repair have to remember this artery might be there.

Ankle sprains

Most frequently injured major joint in the body. ankle sprains (from fibers of ligaments) are most common. Sprained ankle is nearly always an inversion injury, involving twisting of the weight bearing plantarflexed foot. Anterior talofibular ligament (part of lateral ligament) most commonly torn during ankle sprains, resulting in instability of ankle joint. Calcaneofibular ligament may also be torn. Fracture of lateral malleolus by forced inversion of the foot.

Bunion

Localized swelling at the medial side of the firts metatarsophalangeal joint (or the first metatarsal head) that is caused by an inflammatory bursa and is unusally associated with hallux valgus.

Bunionectomy

Excision of an abnormal prominence on the medial aspect of the first metatarsal head.

Bumper Fracture

Fracture of the lateral tibial condyle that is caused by an automobile bumper. usually associated with a common peroneal nerve injury.

Bone grafts

Fibula is common source of bone for grafting. Free vascularized fibias have been used to restor skeletal integrity to limbs with congenital bone defects exist and to replace segments of bone after trauma or excision of malignant tumor. Periosteum and nutrient artery are removed with piece of bone so graft will stay alive and grow when transplanted. Transplanted piece eventually restores blood supply of bone where its attached

Bursitis in knee region

Prepatellar bursitis "housemaid's knee" is friction bursitis caused by friction between skin and patella. If inflammation is chronic, bursa becomes distended with fluid and forms edema anterior to knee. Subcutaneous intrapatellar bursitis results from friction between skin and tibial tuberosity. Deep Infrapatellar bursitis results in edema between patellar ligament and tibia, superior to tibial tuberosity. suprapatellar bursa communicated with articular cavity of knee joint - abrasions or wounds superior to patella may resuly in suprapatellar bursitis caused by bacteria.

Chondromalacia Patellae

Runner's knee - common problem for marathon runners. Soreness and aching around or deep to patella results from quadriceps imbalance. May also result from a blow to the patella or extreme flexion of the knee.

Containment and spread of compartmental infections in leg

Fascial compartments are generally closed spaces because septa and deep fascia of leg forming bound are strong increase volume consequent to infection with suppuration (form of pus) increase intracompartmental pressure inflammation of anterior and posterior compartments spread chiefly in distal direction but purulent infection in lateral compartment can ascend proximally to popliteal fossa along fiblar nerve. Fasciotomy may be done to relieve pressure.

Injury to common Fibular Nerve and Foot Drop

Most often injured in lower limb because of its superficial position, mainly because it wraps around fibular neck = vulnerable to trauma. Nerve can be severed by fx of fibular neck or stretched when knee is injured or dislocated. severance of common fibular nerve = flaccid paralysis of all muscles in anterior and lateral compartment of the leg - dorsiflexors of ankle and evertors of foot. Loss of dorsiflexion of ankle causes foot drop = makes the limb too long

Calaneal tendon reflex

ankle reflex if elicited by striking the calcaneal tendon briskly with reflex hammer while pts legs are dangling over side of exam table. Tendon reflex tests S1 and S2 nerve roots. If S1 nerve root is cut or compressed, ankle reflex almost virtually absent

Calcaneal Bursitis

Results from inflammation of bursa of calcaneal tendon located between calcaneal tendon and the superior part of posterior surface of calcaneus. Causes pain posterior to heel and occurs commonly during long distance running, basketball and tennis. Caused by excessive friction on bursa as calcaneal tendon continuously slides over it.

Inflammation and rupture of calcaneal tendon

Inflammation of calcaneal tendon - 9 to 18% of running injuries. Microscopic tears of collagen fibers in the tendon, particularly superior to its attachment to calcaneous = tendonitis (pain with walking). Rupture is often sustained by patiens with calcaneal tendinitis. After rupture, passive dorsiflexion is excessive and plantarflexion against resistance can't be done

Intermittent Claudication

condition of limping caused by ischemia of the muscles in the lower limbs, chiefly the calf muscles, and is seen in occlusive peripheral arterial diseases particularly in the popliteal artery and its branches. Main symptom is leg pain that occurs during walking and intensifies until walking is impossible, but the pain is relieved by rest.

Cruciate anastamosis of butt

formed by an ascending branch of the first perforating artery, the inferior gluteal arter and the transverse branches of the medial and lateral femoral circumflex arteries. The cruciate anastomosis bypasses an obstruction of the external iliac or femoral artery.

Corona Mortis

(crown of death) defined as the vascular anastomoses between the obturator and external iliac systems. A vascular anastomosis between pubic branches of the obturator arter and of the external iliac (or inferior epigastric) is called the corona mortis because these vessels in the retropubic area are hard to distinguish and can be injured in groin or pubic surgery, leading to massive uncontrolled bleeding. Since a venous connection is more probably than an arterial one, surgeons dealing with inguinal and femoral hernias should avoid venous bleeding and need to be aware of these anastomses and their close proximity to the femoral ring.

Club Foot

(Talipes equinovarus) congenital deformity of the foot in which the foot is plantarflexed, inverted, and adducted. May involve a deformity in which the foot is plantarflexed (equinus) or dorsiflexed (calcaneus) and the heel is turned laterally (valgus) or medially (varus) in which the heel is elevated and turned laterally (equinovalgus) or medially (equinovarus) or in which the anterior part of the foot (forefoot) is elevated and the heel is turned laterally (calcaneovalgus) or medially (calcaneovarus).

Charley horse

(Muscle cramp) sudden, involuntary, painful contraction of muscles of the lower limb. It is caused by muscle fatigue, overexertion, dehydration, and depletion or imbalance of salt and minerals (electrolytes) such as Calcium, sodium, potassium and magnesium. A poor blood supply to leg muscles caused by smoking and atherosclerosis can cause claudication. Most common affected muscles are calf (gastrocnemius), hamstrings, and quadriceps. the cramp goes away within a few minutes or it can be treated by a gentle stretch and massage of the cramped muscle, pain relievers and muscle relxors.

Coxa Vara

alteration of the angle made by the axis of the femoral neck to the axis of the femoral shaft so that the angle is less than 135 degrees, the femoral neck becomes more horizontal.

Coxa Valga

Alteration of the angle made by the axis of the femoral neck to the axis of the femoral shaft so that the angle exceed 135 degress, the femoral neck becomes straighter

Compartment Syndrome in leg

Fascial compartments of the lower limbs are generally closed spaces. Trauma to muscles can produce hemorrhage, edem and inflammation becasue septa and deep fascia are strong. increased volume increase intracompartmental pressure. Small vessels of muscles and nerves are at risk of compression. Structures distal to compressed area may become ischemic and permanantely injured. Increased pressure in confined area decreases circulation and threatens function and viability of tissue within or distally.

Distal femur fracture

May injure the popliteal artery becasue of its deep position adjacent to the femur and the knee joint capsule

Palpation of Dorsalis Pedis Pulse

Dorsalis pedis artery pulse is evaluated during a physical exam of peripheral vascular system. Pulse may be felt with feet slightly dorsiflexed. Easy to feel because dorsal arteries are subcutaneous and pass along a line from extensor retinaculum to a point just lateral to extensor hallucis longus tendons. Diminished pulse means vascular insufficiency from arterial disease. remember the 5 P's of acute arterial occlusion.

5 P's of Acute Arterial Occlusion

Pain, Pallor, Parethesia, Paralysis and Pulselessness.

DVT**

Deep venous thrombosis - characterized by swelling, warmth, erythema and infection. Venous stasis (stagnation) is an important cause of thrombus formation. Venous stasis can be caused by 1. loose fascia that fails to resist muscle expansion, decreasing the effectiveness of musculovenous pump. 2. ext pressure on veins (long hospital stay or cast) 3. muscular inactivity

Deep fibular nerve entrapment

excessive use of muscles supplied by deep finbular nerve can result in muscle injury and edema in anterior compartment. May cause compression of deep fibular nerve and pain in anterior compartment. Compression of nerve can happen where the nerve passes deep to inferior extensor retinaculum and the extensor hallucis brevis. Pain occurs in dorsum of the foot and usually radiates to web space between 1st and 2nd toes.

Ski boot syndrome

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Epiphysial plate fractures

Primary ossification center for sup end of tibia appears shortly after birth and joins shaft of tibia during adolescence (16-18). Tibial fx in kids is more serious if they involve epiphysial plates because continues normal growth of the bone may be jeoprodized. Tibial tuberosity forms by inf. bone growth from sup. epiphyseal center at approx. 10, but seperate center may appeart at 12.

Osgood-Schlatter disease*

chronic pain secondary to disuption of epiphysial plate at tibial tuberosity.

Contusion of extensor digitorum brevis

location of extensor digitorum brevis is clinically important for distinguishing muscle from abnormal edema. Contusion and tearing of muscle fibers and associated blood vessels results in hematoma, producing edema anteromedial to lateral malleolus. Most people who haven't seen this inflammed muscle assume they have a severely sprained ankle

Femoral Artery

Easily exposed and cannulated at the base of the femoral triangle just inferior to the midpoint of the inguinal ligament. The superficial position of the femoral artery in the femoral triangle makes it vulnerable the injury by laceration and gunshot wounds. When it is necessary to ligate the femoral artyer, the cruciate anastomosis supplies blood to the thigh and leg.

Foot drop

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Femoral Nerve damage

Causes impaired flexion of the hip and impaired extension of the leg resulting from paralysis of the quadriceps femoris.

Forced eversion of the foot

avulses the medial malleolus or ruptures the deltoid ligament.

Fibula fracture

commonly occur proximal to lateral malleus and are often associated with fracture-dislocations of ankle. Person slips, forces foot into excessively inverted position, ankle ligaments tear, forcibly tilting the talus against the malleolus and shearing it off

fibular neck fracture

May cause an injury to the common peroneal nerve which winds laterally around the neck of the fibula. Injury results in paralysis of all muscles in the anterior and lateral compartmens of the leg (dorsiflexors and evertors of the foot) causing foot drop.

Femoral Fractures

neck of femur - most frequently fractured - especially in females with osteoporosis. Fx of proximal femur can occur at several locations. Femoral shaft is large and strong but a violent, direct injury may fracture it. Fractures of distal femur may be complicated by seperation of condyles, resulting in misalignment of the knee joint.

Fasciotomy

Loss of distal leg pulses - obvious sign of compression as well as decreased temp of tissues distal to compression. Fasciotomy - incison of overlying fascia or a septum can be performed to relieve pressure in compartment(s) concerned

Hemorrhaging Wounds of sole of foot

Puncture wounds of sole of foot involving deep plantar arch and its branches usually resuly in severe bleeding. Ligature of the arch is difficult because of its depth and the structures surronding it

Fractures of femoral neck (Hip Fractures)

Fractures of femoral neck often disrupts blood supply to head of femur. Medial circumflex femoral artery supplies most of the blood to the head and neck of femur. Its retinacular arteries often are torn when femoral neck is fx or hip joint is dislocated. Sometimes blood supplied to femoral head through the artery to ligament of femoral head may be only source of blood to proximal fragment. Lower limb is shortened with lateral rotation.

Aseptic vascular necrosis

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femoral vein

Lies immediately medial to the femoral artery, which can be identified by feeling the pulsation. Cannulation of the femoral vein permits administration of fluids or catheters, which are passed superiorly through the external and common iliac veins into the inferior vena cava and then right atrium of the heart.

Femoral pulse and cannulation of femoral artery

...

Femoral hernia

morecommon in women than in men, passes through the femoral ring and canal and lies lateral and inferior to the pubic tubercle and deep and inferior to the inginal ligament; its sac if formed by the parietal peritoneum. Strangulation of femoral hernia may occur because of sharp, stiff boundaries of the femoral ring, and the strangulation interferes with the blood supply to the herniated intestine, resulting in death of tissues.

Fracture of foot bones

Calcaneal fractures occur in people who fall on their heels. Usually the bone breaks into several fragments that disrupt the subtalar joint, where the talus articulates with the calcaneus. Fractures of the talar neck may occur during severe dorsiflexion of the ankle. Metatarsal and phalangeal fractures are common injury in endurance athletes and may also occur when a heavy object falls on the foot. Metatarsal fractures are also common in dancers espeically female ballet dancers using the demipointe technique

Gluteal region

Common site for IM injection of medications. Injection should always be made in the superior lateral quadrant of the gluteal region to avoid injury to the underlying sciatic nerve and other neurovascular structures in the medial and inferior quadrants.

Gluteal gait

(Gluteus Medius Limp) is a waddling gait characterized by the pelvis falling toward the unaffected side when the opposite leg is raised at each step. Results from paralysis of the gluteus medius muscle which normally functions to stabilize the pelvis when the opposite foot is off the ground.

Great saphenous vein

accompanies the saphenous nerve, which is vulnerable to injury when it is harvested surgically. Commonly used for CABG and the vein should be reversed so its valves dont obstruct blood flow in the graft. This vein and its tributaries become dilated and varicosed, and vericose veins are common in the posteromedial parts of the lower limb

Genu Varum

(Bowleg) deformity in which the tibia is bent medially. It may occur as a result of collapse of the medial compartment of the knee and rupture of the lateral collateral ligament.

Genu Valgum

(Knock-knee) deformity in which the tibia is bent or twisted laterally. It may occur as a result of collapse of the lateral compartment of the knee and rupture of the medial collateral ligament.

Gracilis

relatively weak member of the adductor group of muscles so surgeons often transplant the muscle or part of it, with nerve and blood vessels, to replace damaged muscle in the hand. Proximal muscle attachments are in the inguinal region or groin.

Groin pull

Strain, stretching or tearing of the origin of the flexor and adductor of the thigh and often occurs in sports that require quick starts

Gastrocnemius strain

...

Hemarthosis

(blood in the joint) usually causes a rapid swelling of the injured knee joint, whereas inflammatory joing effusion causes a slow swelling of the knee joint

Hamstring Injury

(Injury, strain, pulled or torn) common in persons who are involved in running, jumping and quick start sports. The origin of the hamstrings from the ischial tuberosity may be avulsed, resulting in rupture of blood vessels. Avulsion of the ischial tuberosity may result from forcible flexion of the hip with the knee extended, and tearing of hamstring fibers is very painful.

Hallux Valgus

lateral deviation of the big toe and is frequently accompanied by swelling on the medial aspect of the first metatarsophalangeal joint.

Dislocation of Hip - Acquired

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Surgical hip replacement

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Dislocation of hip - Congenital

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Hip fracture

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Hip and thigh contusions

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Enlarged Inguinal Lymph nodes

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Intragluteal injections

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Knee replacement

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Arthroscopy of knee joint

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Knee joint injuries

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Knee dislocation

may injure the popliteal artery because of its deep position adjacent to the femur and the knee joint capsule

Medial femoral circumflex artery

Clinically important because its branches run through the neck to reach the head and supplies most of the blood to the neck and head of femur except for the small proximal part that receives blood from a branch of the obturator artery.

Medial Plantar Nerve Entrapment

...

March Fracture

(Stress Fracture) fatigue fracture of one of the metatarsals, which may result from prolonged walking. Metatarsal fractures are also common in female ballet dancers when the dancers lose balance and put their full body weight on the metatarsals.

Medial Meniscus

More frequently torn in injuries than the lateral meniscus because of its strong attachment to the tibial collateral ligament

Obturator nerve injury

causes a weakness of adduction and a lateral swinging of the limb during walking because of the unopposed abductors.

Phantom Limb pain

Intermittent or continuous pain perceived as originiating in an absent (amputated) limb.

Piriformis Syndrome

Condition in which the piriformis muscle irritates and places pressure on the sciatic nerve, causing pain in the butt and referring pain along the course of the sciatic nerve. Can be treated with progressive piriformis stretching, corticosteriod, or surgical exploration.

Pillion Fracture

T-shaped fracture of the distal femus with displacement of the condyles. It may be caused by a blow to the flexed knee of a person riding pillion on a motorcycle.

Posterior Drawer Sign

backward sliding of the tiba on the femur caused by a rupture of the posterior cruciate ligament

Prepatellar Bursitis

(housemaid's knee) inflammation and swelling of the prepatellar bursa

Popliteal cysts

(Baker's cyst) swelling behind the knee, caused by knee arthritis, meniscus injury, or herniation or tear of the joint capsule. It impairs flexion and extension of the knee and the pain gets worse when the knee is fully extended. Can be treated by draining and decompressing the cyst

Patellar tendon Reflex

A tap of the patellar tendon elicits extension of the knee joint. Both afferent and efferent limbs of the reflex arch are in the femoral nerve (L2-L4)

Popliteal Pulse

...

Popliteal Aneurysm

Usually results in edema and pain in the popliteal fossa. If it's necessary to ligate the femoral artery for surgical repair, blood can bypass the occlusion through the genicular anastomoses and reach the popliteal artery distal to the ligation.

Absence of Plantarflexion

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Plantar Fasciitis

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Plantar reflex

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Patellofemoral Syndrome

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Patellar dislocation

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Pes Planus (Flat feet)

condition of disappearance or collapse of the medial longitundinal arch with eversion and abduction of the forefoot and causes greater wear on the inner border of the soles and heels of shoes than the outer border. It causes pain as a result of stretching of the plantar muscles and straining of the spring ligament and the long and short plantar ligaments.

Pertrochanteric Fracture

femoral fracture through the trochanters and is a form of the extracapsular hip fracture. More common in elderly women than men because of increased incidence of osteoporosis

Pott's fracture - Dislocation of Ankle

Fracture of the lower end of the fibula, often accompanied by fracture of the medial malleolus or rupture of the deltoid ligament. It's caused by forced eversion of the foot.

Regional nerve blocks of Lower Limb

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Parlysis of Quadriceps

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Steppage Gait

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Swingout gait

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Shin Splint

painful condition of the anterior compartment of the leg along the thin bone (tibia) caused by swollen muscles in the anterior compartment, particularly the tibialis anterior muscle, following athletic overexertion. May be a mild form of anterior compartment syndrome.

Injury to Superior Gluteal Nerve

causes a characteristic motor loss, resulting in weakened abduction of the thigh by the gluteus medius, a disabling gluteus medius limp and gluteal gait.

Injury to Sciatic Nerve

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Superficial Fibular Nerve Entrapment

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Sural Nerge Grafts

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Abnormalities of Sensory Function

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Saphenous Cutdown and Saphenous Nerve Injury

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Tibial Nerve Entrapment

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Transverse Patellar Fracture

results from a blow to the knee or from sudden contraction of the quadriceps muscle. Proximal fragment of the patella is pulled superiorly with the quadriceps tendon and the distal fragment remains with patellar ligament.

Trendelenburg's Sign

seen in a fracture of the femoral neck, dislocated hip joint or weakness and paralysis of the gluteus medius and minimus muscle, causing inability to abduct the hip. If the right gluteus medius and minimus muscles are paralyzed, the unsupported left side of the pelvis falls instead of rising

Tarsal Tunnel Syndrome

complex symptom resulting from compression of the tibial nerve or its medial and lateral plantar branches in the tarsal tunnel, with pain, numbness and tingling sensations on the ankle, heel, sole of foot. It may be caused by repetitive stress with activities, flat feet, or excess weight.

Tibia Fractures

Tibial shaft is narrowest at the junction of its inferior and middle thirds, which is the most common site of fracture. Because its anterior surface is subcutaneous, the tibial shaft is the most frequent site of a compound fracture, one in which the skin is perforated and blood vessels are torn. Fx of tibia through the nutrient canal predisposes to nonunion of the bone fragments, resulting from damage to the nutrient artery.

Thrombophlebitis

venous inflammation with thrombus formation that occurs in the superficial veins in the lower limb, leading to PE. Most PEs originate in deep veins and the risk of embolism can be reuced by anticoagulant treatment.

Trochanteric and Ischial Bursitis

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Tibials Anterior Strain

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Posterior Tibial Pulse

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Injury to Tibial nerve

Causes loss of plantar flexion of the foot and impaired inversion resulting from paralysis of the tibialis posterios and causes a difficulty in getting the heel off the ground and a shuffling of the gait. Results in characteristic clawing of the toes and secondary loss on the sole of the foot, affecting posture and locomotion.

Unhappy triad of knee

May occur when a football player's cleated shoe is planted firmly in the turf and the knee is struck from the lateral side. It's indicated by a knee that is markedly swollen, particularly in the suprapatellar region, and results in tenderness on application of pressure along the extent of the tibial collateral ligament. It is characterized by a) rupture of the tibial collateral ligament, as a result of excessive abduction b) tearing of the anterior cruciate ligament, as a result of forward displacement of the tibia and c) injury to the medial meniscus, as a result of the tibial collateral ligament attachment.

Vericose Veins

develop in the superficial veins of the lower limb because of reduced elasticity and incompetent valves in the veins or thrombophlebitis of the deep veins.

Waddling Gait

...

Dislocation of femoral head

Usually associated with advanced age and requires a hip repalcement. Presents as shortened lower limb with medial roation.

Patella ligament

portion of can be used for surgical repair of the anterior cruciate ligament or the knee joint.

Tendon of the plantaris muscle

can be used for tendon autografts to the long flexors of the fingers

Hallux varus

medial deviation of the big toe

Sciatica

referred pain from piriformis syndrome in the lower back and hip that radiates down the back of the thigh and into the lower back

Anterior dislocation subluxation of the hip joint

characterized by tearing of the joint capsule anteriorly with movement of the femoral head out from the acetabulum; the femoral head lies anteroinferior to the pubic bone or the acetabulum.

Posterior dislocation of the hip joint

characterized by posterior tearing of the joint capsule, resting the fractured femoral head on the posterior surface of the ischium, as occurs in head on collision. Results in probably rupture of both the posterior acetabular labrum and the ligamentum capitis femoris and usually injury of the sciatic nerve. Results in affected limb being shortened, adducted and medially rotated.

Medial or intrapelvic dislocation of the hip joint

characterized by tearing of the the joint capsule medially and the dislocated femoral head lies medial to the pubic bone. May be accomplished by acetabular fracture and rupture of the bladder.

Forced inversion of the foot

avulses the lateral malleolus or tears the lateral collateral (anterior and posterior talofibular and calcaneofibular) ligament

Pes Cavus

exhibits an exaggerated height of the medial longitudinal arch of the foot

Damage to sciatic nerve

Causes impaired extension at the hip and impaired flexion at the knee, loss of dorsiflexion and plantar flexion at the ankle, inversion and eversion of the foot, and peculiar gait because of increased flexion at the hip to lift the dropped foot off the ground.

Damage to superficial fibular nerve

causes no foot drop but does cause loss of eversion of the foot

Damage to deep fibular never

results in foot drop and hence a characteristic high-stepping gait

Foot drop

loss of dorsiflexion

Aberrant obturator artery

may arise from the external iliac or inferior epigastric artery and is vulnerable during surgical repair of a femoral hernia.

dancer's fracture

when the dancer loses balance, putting the full body weight on the metatarsal and fracturing the bone.

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