<unk>  is swollen, firm, tender with squeezing
Usually develops soon after significant trauma
May be delayed up to 48hr after the event
May be delayed up to 48hr after the event
Classic signs of disruption in arterial flow, not of<unk> 
Only found once arterial flow has stopped (very late finding)
Only found once arterial flow has stopped (very late finding)
Severe, out of proportion to physical findings
Worse with passive stretch of distal body part such as toes or fingers (muscle extension > increased volume > increased pressure)
Often the presenting symptom.
Occurs in sensory distribution of affected nerve
Anterior
Nerve: deep fibular (peroneal): sensation of 1st webspace
Muscle: tibialis anterior: foot/ankle dorsiflexion
Lateral
Nerve: superficial fibular (peroneal) nerve: sensation of lateral aspect of lower leg, dorsum of foot
Muscle: peroneus longus and brevis: foot plantarflexion
Deep posterior
Nerve: posterior tibial nerve: sensation of plantar aspect of foot
Muscle: tibialis posterior/flexor hallucis longus/flexor digitorum longus: Pain with passive extension of the toes
Superficial posterior
Nerve: sural cutaneous nerve: sensation of lateral aspect of foot
Muscle: gastrocnemius/soleus/plantaris: weakness of plantar flexion
Nerve: deep fibular (peroneal): sensation of 1st webspace
Muscle: tibialis anterior: foot/ankle dorsiflexion
Nerve: superficial fibular (peroneal) nerve: sensation of lateral aspect of lower leg, dorsum of foot
Muscle: peroneus longus and brevis: foot plantarflexion
Nerve: posterior tibial nerve: sensation of plantar aspect of foot
Muscle: tibialis posterior/flexor hallucis longus/flexor digitorum longus: Pain with passive extension of the toes
Nerve: sural cutaneous nerve: sensation of lateral aspect of foot
Muscle: gastrocnemius/soleus/plantaris: weakness of plantar flexion
Crush injury, with or with out associated fracture
Involved<unk> s: thenar, hypothenar, adductor pollicis, and 4 interossei muscles
Diagnosis
Clinical, not based on actual<unk>  pressure
Pain
Deep, constant, poorly localized, out of proportion to exam
"Intrinsic minus" position at rest
MCP joint extended with proximal IP joint slightly flexed
Pain with passive stretch of involved<unk> al muscles
Interosseus: performed with MCP joint extended and PIP jionts fully flexed
Thenar, hypothenar: performed by extension of MCP joint
Tense swelling of affected<unk> 
Clinical, not based on actual<unk>  pressure
Pain
Deep, constant, poorly localized, out of proportion to exam
"Intrinsic minus" position at rest
MCP joint extended with proximal IP joint slightly flexed
Pain with passive stretch of involved<unk> al muscles
Interosseus: performed with MCP joint extended and PIP jionts fully flexed
Thenar, hypothenar: performed by extension of MCP joint
Tense swelling of affected<unk> 
Deep, constant, poorly localized, out of proportion to exam
MCP joint extended with proximal IP joint slightly flexed
Interosseus: performed with MCP joint extended and PIP jionts fully flexed
Thenar, hypothenar: performed by extension of MCP joint
Associated with supracondylar fracture (peds), distal radius fracture (adults)<unk> s
Dorsal (highest risk)
Volar
Dorsal (highest risk)
Volar
Number of<unk> s is controversial, but at least 4, up to 9
Medial, lateral, central, interosseous, adductor
Mechanism - crush injuries
Other mechanisms - foot surgery, Lisfranc fracture, cast immobilization, prolonged extremity positioning, snake bites, severe ankle sprains with arterial disruption
5-17% of calcaneus fractures result in<unk> 
Diagnosis
Pain out of proprtion
Pain worse with passive dorsiflexion (stretching intrinsic musculature of foot); concurrent metatarsal fracture cloud this finding
Do not rely on absent pulse or complete anesthesia, which are late findings
Measure absolute<unk>  pressures in insertion sites found here
Treatment
Elevate extremity to level of heart (above the heart, and there will be reduction of O2 perfusion)
SCDs may help decrease interstitial pressure, improve venous return/arterial flow
Fasciotomy within 24 hrs of injury if pressures > 30 mmHg
Medial, lateral, central, interosseous, adductor
Mechanism - crush injuries
Other mechanisms - foot surgery, Lisfranc fracture, cast immobilization, prolonged extremity positioning, snake bites, severe ankle sprains with arterial disruption
5-17% of calcaneus fractures result in<unk> 
Diagnosis
Pain out of proprtion
Pain worse with passive dorsiflexion (stretching intrinsic musculature of foot); concurrent metatarsal fracture cloud this finding
Do not rely on absent pulse or complete anesthesia, which are late findings
Measure absolute<unk>  pressures in insertion sites found here
Treatment
Elevate extremity to level of heart (above the heart, and there will be reduction of O2 perfusion)
SCDs may help decrease interstitial pressure, improve venous return/arterial flow
Fasciotomy within 24 hrs of injury if pressures > 30 mmHg
Pain out of proprtion
Pain worse with passive dorsiflexion (stretching intrinsic musculature of foot); concurrent metatarsal fracture cloud this finding
Do not rely on absent pulse or complete anesthesia, which are late findings
Measure absolute<unk>  pressures in insertion sites found here
Elevate extremity to level of heart (above the heart, and there will be reduction of O2 perfusion)
SCDs may help decrease interstitial pressure, improve venous return/arterial flow
Fasciotomy within 24 hrs of injury if pressures > 30 mmHg<unk>  enclosed on the lateral, dorsal and ventral aspects by thoracolumbar fascia and medial aspect by spinous processes and interspinous ligaments
Mechanisms
Direct trauma
Atraumatic mechanism (Heavy weight lifting)
Typically males in their 20's and 30's
Recent surgery causing compromised blood supply
Characteristics
Pain of the low back refractory to analgesia
Radiation of pain to the groin
Tender and tense lumbar paraspinal muscles
Loss of normal lumbar lordosis
Worsening of pain with hip flexion
Concurrent ileus in some cases
Diagnosis
Elevated CK
Elevated<unk>  pressures
Imaging not required
If imaging is performed, MRI is the test of choice
MRI will demonstrate enhancement of the paraspinal muscles on T2-weighted images
CT is less helpful, but can exclude other causes of low-back pain such as fracture
Treatment is with emergent fasciotomy and with fluid resuscitation for any concurrent rhabdomyolysis 
Direct trauma
Atraumatic mechanism (Heavy weight lifting)
Typically males in their 20's and 30's
Recent surgery causing compromised blood supply
Typically males in their 20's and 30's
Pain of the low back refractory to analgesia
Radiation of pain to the groin
Tender and tense lumbar paraspinal muscles
Loss of normal lumbar lordosis
Worsening of pain with hip flexion
Concurrent ileus in some cases
Elevated CK
Elevated<unk>  pressures
Imaging not required
If imaging is performed, MRI is the test of choice
MRI will demonstrate enhancement of the paraspinal muscles on T2-weighted images
CT is less helpful, but can exclude other causes of low-back pain such as fracture
If imaging is performed, MRI is the test of choice
MRI will demonstrate enhancement of the paraspinal muscles on T2-weighted images
CT is less helpful, but can exclude other causes of low-back pain such as fracture
Thigh (quadriceps<unk> 
Buttock (gluteal<unk> 
Arm (deltoid, biceps<unk> s)
Abdominal
Compartment syndrome
Crush syndrome
Contusion
Cytokine release syndrome
NSAID toxicity
Degloving injury
Pancoast syndrome
Morel-Lavallée lesion