Posterior Thigh and Popliteal Fossa Flashcards
Common proximal attachment of posterior thigh muscles
Ischial tuberosity- except short head of biceps femoris
Common innervation of posterior thigh muscles
Tibial division of sciatic nerve- except short head of biceps femoris
Common functions of posterior thigh muscles
Leg flexion at knee
Thigh extension at hip- except short head of biceps femoris
Semitendonosus OINA
O: ischial tuberosity
I: pes anserinus - anteromedial superior tibia
N: Tibial division of sciatic nerve
A: extend thigh, flex leg, medially rotate flexed leg
Attachments to pes anserinus listed superficial to deep
Sartorius
Gracilis
Semitendonosus
Pes anserine bursitis
Inflammation of anserine bursa located between pes anserinus and the MCL
Results in constant, aching pain aggravated by activity such as climbing stairs, specifically flexion and internal/medial rotation of knee
Semimembranosus OINA
O: ischial tuberosity
I: posterior part of medial tibial condyle
N: tibial division of sciatic nerve
A: extend thigh, flex leg, medially rotate flexed leg
Semimembranosus distal tendon- explain
Divides into 2 main parts, one goes to medial tibial condyle, the other becomes oblique popliteal ligament
This ligament reinforces intercondylar portion of knee joint capsule and forms part of popliteal fossa floor
Biceps femoris long head OINA
O: ischial tuberosity
I: lateral aspect of fibular head
N: tibial division of sciatic nerve
A: extend thigh, flex leg, laterally rotate flexed leg
Biceps femoris short head OINA
O: lateral lip of linea aspera and lateral supracondylar line
I: lateral aspect of fibular head
N: common fibular division of sciatic nerve
A: flex leg, laterally rotate flexed leg
Grade I hamstring injury
Mild
Small disruption in structural integrity
Minor swelling and pain
No or minimal loss of strength
Grade II hamstring injury
Moderate
Partial tears with some intact muscle fibers
Pain present
Definite loss of strength
Grade III hamstring injury
Severe
Complete tear
Swelling, severe pain and typically with accompanied hematoma
Complete loss of motor function
Perforating arteries of deep femoral/profundal femoral artery
There are three perforating branches, and the termination of the deep femoral artery becomes the 4th branch
Supplies posterior thigh muscles and adductor magnus
Courses from anterior from posterior by piercing adductor magnus
Descending branch of lateral femoral circumflex artery
Descends anterior thigh
Supplies genicular anastomosis
Descending genicular artery
Arises from femoral artery in adductor canal
Supplies genicular anastomosis
Sciatic nerve tibial division innervates
L4-S3 Long head of biceps femoris L5-S2 Semitendinosus L5-S2 Semimembranosus L5-S2 Hamstring portion of adductor magnus (L4)
Common fibular division of sciatic nerve innervates
L4-S2
Short head of biceps femoris L5-S2
Semitendinosus OINA
O: ischial tuberosity
I: pes anserinus
N: tibial division of sciatic nerve
A: extend thigh, flex leg and rotate it medially
Boundaries of the popliteal fossa
Superomedially: semimembranosus, semitendinosus
Superolaterally: Biceps femoris
Inferolaterally: lateral head of gastrocnemius
Inferomedially: medial head of gastrocnemius
Contents of popliteal fossa listed superficial to deep
Tibial nerve, common fibular nerve, sural nerve
Popliteal vein, branches and lymph nodes
Popliteal artery and branches
Popliteal artery
Continuation of femoral artery after passing through adductor hiatus
Terminates by dividing into anterior/posterior tibial arteries
Deepest structure in popliteal fossa
Gives rise to genicular branches
Genicular anastomosis
Important collateral circulating bypassing popliteal artery if knee is fully flexed for long periods of time or if there are narrowed/occluded popliteal vessels
Supplies articular capsule and ligaments of knee joint
Includes: Popliteal artery, descending branch of lateral femoral circumflex artery, descending genicular artery saphenous and articular branches.
Popliteal vein
Lies superficial to and in same fibrous sheath as popliteal artery
Termination point of small saphenous vein
Formed by union of anterior/posterior tibial veins, usually near inferior border of popliteus muscle
Becomes femoral vein after traversing adductor hiatus
Popliteal fossa lymphatics
Cutaneous fluid drains to superficial popliteal nodes along small saphenous vein
Deep leg and foot drains to deep popliteal nodes along popliteal vein
Proximal drainage accompanies femoral vein to deep inguinal nodes
Continued drainage follows venous return
Tibial nerve
Larger of sciatic nerve (which divides into tibial/fibular nerves near superior angle of popliteal fossa)
Descends centrally through popliteal fossa
Most superficial relative to popliteal vein/artery
Runs distally with posterior tibial artery/vein
Tibial nerve innervates
Posterior leg muscles
Knee joint
Skin on posterior leg via medial sural cutaneous nerve
Common fibular nerve
Descends obliquely on lateral side of popliteal fossa, medial to biceps femoris
Leaves popliteal fossa by passing superficially to lateral head of gastrocnemius
Winds around head and neck of fibula (susceptible to injury)
Common fibular nerve innervates
Anterior leg muscles via deep fibular nerve
Lateral leg muscles via superficial fibular nerve
Skin on posterolateral leg via lateral sural cutaneous nerve
Sural nerve
Cutaneous nerve of posterior leg and lateral aspect of ankle and foot
Runs inferiorly with small saphenous vein, passes inferior to lateral malleolus to lateral side of foot
Composed of medial sural cutaneous nerve from tibial, and sural communicating branch from common fibular or lateral sural cutaneous nerve
Superficial fibular nerve innervates
Fibularis longus/brevis and skin on distal third of anterior surface of leg and dorsum of foot
Deep fibular nerve innervates
Anterior muscles of leg, dorsum of foot, skin of first interdigital cleft, sends articular branches to joints it crosses
Metaphyseal distal femoral fracture
Traverse fracture across the shaft
Most common distal femoral fracture
Physeal distal femoral fracture
Transverse fracture involving epiphyseal plate
Commonly described by Salter-Harris classification:
I- through growth plate
II- through growth plate and metaphysis
III- through growth plate and epiphysis
IV- through all three elements
V- crush injury of growth plate
Distal femoral fracture may disrupt what and how
Posterior displacement can disrupt neurovasculature due to close proximity to femur in popliteal fossa
Distal femoral fracture nerve injury
Motor injury with foot drop
Sensory deficits to dorsal or plantar foot
Acute compartment syndrome
Increased pressure in a closed fascial compartment
Most commonly due to hemorrhage and/or edema
Symptoms- persistent deep ache/burning pain
Paresthesia
Pain with passive stretch
Muscle weakness
Popliteal (bakers) cysts
Swelling in the popliteal fossa due to enlargement of the gastrocnemius-semimembranosus bursa
Often communicates with knee joint space, and contain synovial fluid
Associated with degenerative inflammatory joint disease or joint injury
Very asymptomatic and typically detected by imaging studies performed for other reasons
Complications of popliteal cysts- enlargement
Presents similar to DVT Erythema and edema due to vein compression Ischemia due to arterial compression Nerve entrapment Positive Homans sign
Complications of popliteal cysts- rupture
Simulates thrombosis or muscle rupture Warmth, tenderness and erythema Ecchymoses Compartment syndromes My be indolent with only edema
Peripheral aneurysm
Localized enlargement of an artery due to weakening of arterial wall
Popliteal artery aneurysms are most common true peripheral aneurysm
Symptoms: claudication or ischemic pain at rest, sensory/motor nerve deficit, severe pain behind knee
Peripheral artery disease
Atherosclerosis leading to peripheral artery occlusion
Lack of blood flow leads to pain in affected muscle groups
Symptoms: ischemic pain at rest, non-healing ulcer, gangrene
