MSK Flashcards
IBD is associated with what arthropathy?
Spondyloarthritis
Pulmonary fibrosis is associated with what arthropathy?
Rheumatoid arthritis
Lumbar stenosis pain worsens with what movement?
Lumbar extension
Herniated disc pain worsens with what movement?
Lumbar flexion, sitting
Compression fracture pain worsens with what movements?
Sitting and standing
How is mild radiculopathy diagnosed and treated?
Clinically, no need for imaging
NSAIDs, glucocorticoids if severe pain
Left diaphragm referred pain is where, and can be caused by what?
Left shoulder; contained splenic bleed
Under what cases does alk phos represent bone metastases?
Osteoblastic, not osteolytic, metastases
MM and renal cell are osteolytic
Ganglion cyst differential diagnosis
Ganglion cyst: round, rubbery, transilluminates - observation/needle aspiration/surgery
Epidermal cyst: painful, nontransilluminating, overlying punctum - use corticosteroids
RA nodule: hard, fixed, nontransilluminating
How does treatment of clavicular injury depend on which part is fractured?
Middle third: closed reduction and figure-of-eight brace
Distal third: open reduction and internal fixation
How does magnesium sulfate affect skeletal and cardiac muscle?
Skeletal muscle - decreased acetylcholine release
Cardiac muscle - prolonged conduction time
What is more typically seen in electrical, rather than thermal, burns?
Direct injury to muscle tissue –> rhabdomyolysis
Vs circumferential constrictive eschar
Which locations are high risk for malunion if stress fracture is suspected?
Fifth metatarsal, anterior tibial cortex; refer to orthopedic surgeon
Stress fracture shows how on imaging?
Hairline lucency or periosteal thickening, but would not see in first 1-2 weeks on x-ray
What does delta pressure on needle manometry correspond to with regards to compartment syndrome?
Delta pressure = diastolic BP - compartment pressure <=30 mm Hg reflects compromised perfusion pressure
When can compartment syndrome be diagnosed clinically?
High risk: e.g. those with limb revascularization
Superior pulmonary sulcus tumor would affect which nerves?
Brachial plexus –> shoulder pain
C8-T1 (ulnar) –> Weakness/atrophy of intrinsic hand muscles, pain/paresthesia of 4th/5th digits and medial arm/forearm
Paravertebral sympathetic chain/cervical ganglion –> Horner syndrome
Superior pulmonary sulcus tumor causes which lymphadenopathy and is from which cancer?
Supraclavicular
Lung adenocarcinoma or squamous cell
How can a spinal epidural abscess form?
Trauma –> hematoma
Classic triad of spinal epidural abscess
- Spinal pain –> radiculopathic pain
- Neurologic deficits
- Fever
In Peyronie disease, fibrous plaques form where?
In the tunica albuginea, reducing elasticity and expansion during erection –> pain, curvature
Peyronie disease treatment
NSAIDs for pain
Pentoxifylline - reduce fibrosis
Intralesional injections of collagenase
Surgery if refractory
Pelvic fracture signs, risks after
- Adducted, internally rotated lower extremity
- Perineal bruising
Risk for posterior urethral injury - abrupt upward motion of bladder and prostate can lead to urethral tearing at bulbomembranous junction
Also risk of bladder rupture
Posterior urethral injury signs
- Blood at urethral meatus
- Inability to void
- Perineal bruising
- High-riding prostate
Perform retrograde urethrography (X-ray with injection of contrast)
Posterior cruciate ligament injury causes, Sx
Causes: Hyperextension or blow to anterior aspect of proximal tibia
Symptoms: Little pain or alteration in range of motion
Patellar dislocation signs
After quick, twisting motion around flexed knee
Lateral displacement with associated tear of medial patellofemoral ligament
Exam: lateral dislocation of patella, decreased extension, hemarthrosis and tenderness along medial patella
Often reduces spontaneously but may require closed reduction
Follow with X-ray to rule out additional injuries
Patellofemoral syndrome - signs
More common in women
Anterior pain worsened by squatting, climbing stairs, prolonged sitting
Pain and crepitus may be elicited by extending knee while compressing patella
Pes anserinus pain syndrome - signs
Localized pain over anteromedial tibia just below the joint line, often exacerbated by pressure from opposite knee while lying on the side
Absent swelling, erythema, induration
Pes anserinus is formed by conjoined tendons of gracilis, sartorius, and semitendinosus
Bursa located underneath pes anserinus but usually not truly inflamed
Caused by abnormal gait, overuse, or trauma
Treat with quadriceps exercises and NSAIDs
Test for complete supraspinatus tear
Drop arm test - drops rapidly around mid-descent (although it initiates the first 15 degrees of abduction)
MRI to confirm
Long thoracic nerve injury - cause, signs
Caused by penetrating trauma or procedures (e.g. chest tube insertion)
Weakness of serratus anterior with impairment at extreme abduction due to inability to rotate scapula upward
Which nerve injury causes claw hand deformity?
Lower (inferior) trunk of brachial plexus (C8, T1) - ulnar (e.g. intrinsic muscles of hand)
Injured by sudden upward traction on arm (Klumpke palsy)
Which collagen is Ehlers-Danlos?
Type V collagen
Stump hematoma - signs
Swelling
Ecchymosis
Skin breakdown
First several days following amputation
High-impact fall onto outstretched arm typically produces what injury?
Supracondylar humerus fractures (particularly children age 2-7)
Displaced supracondylar humerus fracture can affect which vessel and nerve?
Brachial artery and median nerve - pass anterior to humerus
How would an occult fracture present on X-ray?
Inflammation displaces synovial fat, leading to widened fat pads around the fracture site
Compartment syndrome 4 Ps
- Pallor
- Puleslessness
- Paresthesia
- Paralysis
What signs with penile fracture are concerning for concomitant urethral injury?
- Blood at meatus
- Hematuria
- Dysuria
- Urinary retention
What is the most common dislocation of the humerus? What nerve is injured?
Anteriorly from the glenohumeral joint; also the most commonly dislocated joint in the body
Anterior dislocation caused by blow to externally rotated and abducted arm
Axillary nerve is most commonly injured (teres minor, deltoid) –> weakened shoulder abduction; shoulder sensory innervation
Radial nerve innervation
Extensor muscles of wrist and digits
Sensory posterior arm, forearm, and dorsolateral hand
Commonly injured in humeral midshaft fractures
Biceps reflex - what nerves
C5, C6 - muscular innervation via musculocutaneous nerve (lateral cord of brachial plexus)
Ulnar nerve innervation
Intrinsic muscles of hand
Sensory loss of medial hand
Injured by fracture of medial epicondyle of humerus or deep laceration of anterior wrist
What damage causes scapular winging?
Long thoracic nerve - serratus anterior
Caused by deep lacerations to axillary region and axillary lymphadenectomy
What does a brown recluse spider bite do?
Ischemia leads to burning pain after a few hours
Small papule or in rarer cases blister with bluish discoloration and necrosis extending in gravity dependent manner
Treat with cold, which decreases venom phospholipase activity
Avoid debridement in early necrosis
Commonly when putting clothes on
Can be worse than papule: Forms ulcer —> necrosis, eschar
Growth plate fracture appears how?
Physeal fracture is suggested by growth plate widening on CT
When does the tibial growth plate close in boys/girls?
14/12 yo
Injury to growth plate can cause what complications?
- Growth arrest and limb-length discrepancy
- Physeal bars (bony bridges across growth plate)
- Premature osteoarthritis
- Decreased range of motion
Traumatic foot drop occurs due to damage to what nerve?
Common peroneal nerve as it wraps around lateral neck of proximal fibula
Arm anterior dislocation vs posterior dislocation positions
Anterior: arm held in abduction/external rotation
Posterior: arm held in adduction/internal rotation
When does myositis ossificans occur?
Following fracture or muscle contusion (e.g. quadriceps), typically in lower extremities