Gross Anat Final-Injuries Flashcards
For fractures of femoral neck: why is healing difficult?
Blood supply to femoral head often disrupted –> supplied by medial femoral circumflex a (part of cruciate anastomosis)
- Artery to l. of femoral head may be only remaining source of blood supply to proximal fragment
- ->Proximal fragment may undergo avascular necrosis
Fractures of femoral neck
Most common in women over 60
- Result from indirect trauma
- Intracapsular (no swelling)
- Limb laterally rotated and shortened
- Difficult healing-blood supply to femoral head often disrupted
Intertrochanteric Fractures
Most common in women over 60-direct trauma.
- Swelling present in groin and thigh
- Limb laterally rotated
- Healing is good!
Posterior hip dislocation
Most common-usually car accident.
- Limb flexed, ADD, and medially rotated–causes knees to strike dashboard
- Femoral head forced out of acetabulum, joint capsule ruptures inferiorly and posteriorly
Which nerve is injured in a posterior hip dislocation?
May injure sciatic n.
- Results in paralysis of hamstrings and everything distal to knee
- Sensation affected over posterolateral aspect of leg and much of the foot
- ->Often acetabular margin fractures
Anterior hip dislocation
Result of violent injury –forces limb into extension, ABD and lateral rotation
-Femoral head ends up inferior to acetabular margin
What nerve may be injured in an anterior hip dislocation?
May damage femoral n. –results in paralysis of sartorius m. and quadriceps m.
- Loss of sensation to medial leg and foot
- -> Often acetabular margin fractures
Injury to superior gluteal nerve
Caused by pelvic fracture, wound to gluteal region or compression by fetal head
- Lesion impairs fxn of gluteus medius and minimus mm.
- -> Weakens ABD of thigh, MR also greatly impaired
What does a positive Trendelenburg test (sign) show?
Gluteus med and min. on supported side are weakened, pelvis tilts toward undamaged side and pelvis on unsupported side descends when patient asked to stand on one leg.
–>Shows injury to superior gluteal nerve!
Gluteal gait
Places center of gravity over supporting lower limb
- Descent of pelvis on unsupported side makes that limb “too long”
- Foot won’t clear ground during swing phase, so leans away from injured side raising the pelvis to clear ground
Injury to sciatic nerve in gluteal region
Compression caused by piriformis m –May cause pain in buttock or radiating pain down leg
–> Complete section of sciatic n uncommon
Lateral/medial side of gluteal region
Lateral side “safe” side
-Best place for intragluteal injections is upper lateral quadrant
Medial side “danger” side
-Penetration or surgery here could damage sciatic nerve
Hamstring strain
Common in those who run and/or kick hard w/o proper warm up
-Usually accompanied by bruising and tearing of muscle tissue…extremely painful!
Most commonly torn muscle in a hamstring injury?
Semimembranosus muscle
How does an avulsion of the ischial tuberosity occur?
Forcible flexing of hip with knee extended
–> Proximal part of biceps femoris and semitendinosus mm
Intermittent Claudication
Due to obstruction of femoral, popliteal or posterior tibial aa.
–> Most commonly occurs at adductor hiatus
Intermittent Claudication causes _______ to muscles during exercise
Symptoms?
Causes ischemia (decreased blood flow)
Symptoms:
- Pain in calf and foot when walking –> pain usually disappears with rest
- May show decreased pulse below blockage
Saphenous vein grafts
Great saphenous vein is sometimes used for coronary artery bypass grafts (CABG)
- Used to bypass blocked arteries
- -> Vein is inverted so valves don’t block blood flow
- Rarely produces problems yay!
Injury to femoral nerve
May be injured by pelvic fracture, psoas abscess, gunshot or other penetrating thigh wound
Results in: weakened flexion of thigh, loss of leg extension, sensation to anterior and parts of medial thigh
–> Anteromedial leg and foot via saphenous vein
Difficulties associated with injury to femoral nerve
Difficult to walk uphill or up stairs
–> Person will push against thigh to force knee into extension
Injury to femoral nerve
–> Patellar ligament and knee jerk reflex
Myotatic (deep tendon) reflex
- Striking patellar l of flexed leg should result in extension of knee
- Afferent and efferent limbs of reflex arc are via femoral nerve
- -> If femoral n or L2-4 spinal cord segments are damaged, it will affect this reflex
- -> May also be diminished by peripheral nerve disease
Femoral hernias
More common in females due to wider pelvis
- Protrusion of ab-viscera through femoral ring
- -> Passes through femoral canal
- -> Appears as a mass in femoral triangle
- -> Is located inferolateral to pubic tubercle
Femoral hernias bounded by…
Femoral v–laterally
Lacunar l–medially
Inguinal l–superiorly
Compressed contents of femoral canal
- Hernia is at risk for strangulation
- -> Interferes with blood supply, causes necrosis
Most common knee joint injuries
Ligament sprains!
-Occur when foot is fixed on the ground and force is applied to knee
“Unhappy triad”
Knee joint injuries
Blow to lateral side of extended knee or excessive lateral twisting of flexed knee causes:
- Rupture of TCL
- Concomitant tearing of medial meniscus (due to attachment of TCL)
- Tearing of ACL may also occur
ACL ruptures
Caused by hyperextension or force directed anteriorly when knee is semi-flexed, also common during skiing accidents
- ACL may tear away from tibia or femur, but commonly occur at midpoint
- Causes free tibia to slide anteriorly under fixed femur
- -> Anterior drawer sign
- -> Tested using Lachman test
PCL ruptures
Usually occur in conjunction with FCL or TCL tears
- Occur when knees strike dashboard in car accident
- Allow free tibia to slide posteriorly under fixed femur
- -> Posterior drawer sign
Meniscal tears
Most occurs in conjunction with TCL or ACL tears
- Usually involve medial meniscus
- -> Lateral meniscus less likely to be torn due to mobility
Menisci may be removed
-No loss of mobility, may be less stable, tibial plateau often undergoes inflammatory reactions
Lateral/medial meniscal tears
- Pain with lateral rotation of tibia on femur indicates lateral meniscus tear
- Pain with medial rotation of tibia on femur indicates medial meniscus tear
Exaggerated knee angles
“Q-angle”
Femur is placed diagonally on thigh, whereas tibia is almost vertical in leg
- Creates angle between long axes of bones
- -> Angle is typically greater in adult females due to wider pelvis
How is the “Q-angle” assessed?
- Draw a line from ASIS to middle of patella
- Second vertical line passes through middle of patella to tibial tuberosity
- Normal angle of femur in thigh places middle of knee directly inferior to head of femur when standing
- -> Centers weight-bearing line over intercondylar region of knee
Genu Varum (bowleg)
Medial angulation of leg in relation to thigh, femur abnormally vertical and Q-angle is small
- Line of weight-bearing falls medial to center of knee
- Results in arthrosis (destruction of knee cartilage)
Genu Valgum (knock knee)
Lateral angulation of leg in relation to thigh, larger Q-angle
- Line of weight bearing falls lateral to center of knee
- Results in arthrosis, stresses TCL
- Causes abnormal articulation with patella–pulls it further laterally
Osteoarthritis
Degenerative joint changes
Eventually conditions of exaggerated knee angles lead to osteoarthritis
Fasciotomy
Regarding compartment syndromes
Incision of overlying fascia or septum
–> Performed to relieve pressure I’m compartment concerned
Compartment syndrome
Increased pressure in confined anatomical spaces affects circulation
-Threatens function and viability of tissues
(Fascial compartments of lower limb are closed spaces)
Trauma to muscles and/or vessels in lower limb compartments may produce…
Hemorrhage, edema, and inflammation of muscles
- Results in increased volume of compartment
- -> Strong fascia doesn’t allow accommodation, increases intra-compartmental pressure
Tibialis anterior strain (shin splints)
Mild form of anterior compartment syndrome
- Results from repetitive microtrauma to tibialis anterior m
- -> Causes small tears in periosteum of tibia and/or fleshy attachments to overlying deep fascia
- Edema and pain usually in distal 2/3 of tibia, can decrease blood flow to area
Injury to deep fibular nerve
“Ski boot syndrome”
Can be injured by lacerations, right fitting ski boots or anterior compartment syndrome
High lesion (proximal) injury to deep fibular nerve
Causes pain in anterior compartment
-Affects dorsiflextion, inversion, extension of toes, and sensory loss to area between 1st and 2nd toes
Low lesion (distal) injury to deep fibular nerve
Pain in dorsum of foot
-Sensory loss between 1st and 2nd toes
Fracture of 5th metatarsal
Common in tennis or bball players
- Caused by sudden inversion of ankle
- -> Causes fibularis brevis m to fracture or avulse 5th metatarsal
- Pain and edema around base of 5th metatarsal
- -> Often misdiagnosed as ankle inversion sprain
Injury to superficial fibular nerve
Chronic ankle sprains may stretch this nerve
- Causes pain along lateral side of leg and dorsum of foot
- High lesion would cause weakened eversion
- -> Foot would invert with dorsiflexion
- Sensory loss over anterolateral leg and dorsum of foot
Calcaneal tendon reflex (AKA ankle jerk reflex or triceps surae reflex)
Calcaneal tendon struck with hammer–should result in plantar flexion of foot
- Tests S1-S2 (tibial n)
- -> If S1 damaged, reflex absent
- Tests fxn of gastrocnemius and soleus mm
Calcaneal tendon rupture
Most severe acute muscle injury in leg!
- Occurs in those who are poorly conditioned and have a history of calcaneal tendinitis
- Produces an audible “snap” during forceful push-off
- Followed immediately by calf pain and dorsiflexion of plantarflexed foot
- -> If tendon is completely ruptured, gap is palpable
Calcaneal tendon rupture results in inability to…
Plantarflex against resistance
- Passive dorsiflexion will be excessive
- Ambulation is possible with laterally rotated limb
- -> Usually requires surgical intervention
Injury to tibial nerve in popliteal fossa
Results in:
- Paralysis of flexor mm in leg
- Paralysis of intrinsic mm of plantar foot
- -> Unable to plantarflex foot or flex the toes
- Sensation to sole of foot lost
Injury to tibial nerve at ankle
Injured with trauma to or around medial malleolus
Results in:
-Loss of intrinsic mm of plantar foot
-Sensation over sole of foot
Injury to common fibular nerve
Most commonly injured nerve in lower limb
- May be severed during fracture of fibular neck or stretched with knee dislocation
- Eccentric contraction lost (ability to control foot being lowered to ground–results in distinctive “clop”)
- Sensation lost to anterolateral leg and dorsum of foot
Severance of common fibular nerve results in…
- Flaccid paralysis of all mm in anterior and lateral compartments of leg
- Loss of dorsiflexion causes “foot drop”
- Further exacerbated by unopposed inversion of foot
- Makes limb too long (toes will not clear the ground)
Different gaits to accommodate long limb when common fibular nerve is injured
- Steppage gait
- Waddling gait
- Swing-out gait
Steppage gait
Extra flexion at hip and knee raise foot to keep toes from hitting ground
Waddling gait
Leans to side opposite long limb, hiking the hip
Swing-out gait
Long limb is swung out laterally (ABD) to allow toes to clear the ground
Varicose veins
Affects women more than men
- Can affect great saphenous v or any of its tributaries
- Valves become damaged (incompetent) and no longer function properly
- -> Blood flows inferiorly and vein becomes dilated (varicose)
- -> Also become thick and rope-like
Symptoms of varicose veins
- Pain
- Swelling
- Restless leg
- Burning, itching skin
- Phlebitis
- Skin ulcers
- -> Treated using endovenous laser or stripped
Deep vein thrombosis (DVT)
Thrombus=clot
- Caused by venous stagnation due to muscular inactivity, external pressure on veins, or incompetent fascia that fails to restrict muscle expansion
- Characterized by swelling, warmth, and inflammation/infection
Pulmonary embolism
…in regards to deep vein thrombosis
Large thrombosis may break free and travel to lung
–> If large enough, may block off pulmonary a and cause death
Ankle sprain
Most common ankle injury–tears fibers of ligaments
- Most common type is inversion sprain
- -> Foot forcefully inverted
- Eversion sprains much less common –> involves medial collateral l complex
Inversion ankle sprain
Involves twisting of weight-bearing plantarflexed foot
- Injures lateral ligaments (Tear of anterior talofibular l most common)
- -> Results in instability in ankle joint
- Severe sprain may also injure calcaneofibular l
Ankle fracture
Known as “Pott’s fracture” (Dislocation fracture)
- Occurs when foot is forcefully everted
- Often avulses medial malleolus
- Talus then moves laterally
- -> Shears off lateral malleolus or breaks fibula superior to syndesmosis
“Trimalleolar fracture”
Ankle fracture involving the lateral malleolus, medial malleolus, and the distal posterior aspect of the tibia (“posterior malleolus”)
Pes planus (flatfeet)
Disappearance of medial longitudinal arch
- 3 types:
1. Flexible flatfeet
2. Rigid flatfeet
3. Acquired flatfeet
Flexible flatfeet
Most common type
- Lack medial longitudinal arch when standing
- -> Arch reappears when not weight bearing
- Results from loose or degenerated intrinsic ll
- Common in kids, may persist into adulthood
Rigid flatfeet
Flat even when not bearing weight
- Likely results from bone deformity
- -> Fusion of adjacent tarsals
Acquired flatfeet
“Fallen arches”
- Secondary to dysfunction of tibialis posterior m (dynamic support)
- -> Trauma, age, denervation
- Plantar calcaneonavicular l fails to support talar head
Plantar fasciitis
Most common hindfoot problem in runners
- Inflammation of plantar fascia
- Often caused by overuse
- Causes pain on plantar surface of foot and heel, increases with extension of great toe
- -> Most severe after long period of rest, usually gone within minutes
