MSK Flashcards
pain in the legs that is exacerbated by walking/exercise and relieved by rest
- caused by poor blood flow to muscle, most often caused by atherosclerosis of arteries
Claudication
- popliteal A very common
NOTE: venous blockage (DVT) causes more constant pain and swelling than arterial
fatty acid oxidation defect
- liver failure (increased ammonia, lactate dehydrogenase, aspartate transaminase)
- arrhythmias, seizures, lethargy coma in neonatal form
- milder form presents in adolescence as fatigue after exercise/bad sickness. labs will show rhabdomyolysis
mutation of carnitine palmitoyltransferase 2 (CPT2)
- long-chain acylcarnitines (C16-18) accumulate inside mitochondria and plasma
pathologic fractures, blue sclera, hearing loss
osteogenesis imperfecta (AD) - defect in COL1A1/2
what is the main action of supraspinatous?
abduction of the humerus
- MC rotator cuff injury
patient supine with hips flexed and knees to chest. The patient releases one leg and allows the hip and knee to extend to the table
Thomas test
- for psoas syndrome
patient is in the prone position and the knee is passively flexed 90º. A rotational force is applied to the knee while compression is given from the heel. Pain in the region is considered a positive test
Apley compression test
- for knee meniscus
patient is supine with the knee passively held in 30º of flexion. With one hand, the distal femur is stabilized and with the other hand, a gentle anterior force is applied to the proximal tibia. The unaffected knee must be examined to determine laxity
Lachman test
- more accurate than anterior drawer for ACL
patient is lying on the unaffected side with their hip flexed. The down leg is flexed to 90º at the knee. The operator stabilizes the greater trochanter and holds up the ankle. The thigh is then abducted passively and is extended to catch the ITB over the greater trochanter
Ober test
- for TFL and IT band tightness
patient standing on one leg with the knee flexed to 20º while holding the examiner’s hand for balance. The patient then internally and externally rotates the knee. When pain, locking or a catching sensation is reported, the test is considered positive
Thessaly test
- test is considered superior to other meniscal evaluations if the patient is able to weight bear
weakness of the vastus medialis and abnormal lateral tracking of the patella
patellofemoral pain syndrome
what is the second most likely ligament to tear in a lateral ankle sprain, after ATF?
calcaneofibular (CFL) - type 2 sprain includes both
- type 3 would include posterior talofibular (PTF)
tender to palpation at anatomical snuffbox?
scaphoid fracture likely
inflammation of tibial tuberosity
- pain is usually gradual in onset and abates with rest
- generally self-limiting as long as the patient limits activities
Osgood-Schlatter
- growing pains
- tx is supportive w/NSAIDs and rest
male teen with bony pain, fever, fatigue, weight loss, and possible palpable mass
- Xray shows lamellated or “onion skinning” of periosteum
Ewing sarcoma
- midshaft diaphysis
obese teenagers with hip, thigh, or knee pain and a limp
- present with leg in external rotation that takes pressure off the femoral head
- Xray shows a inferiorly displaced femoral head in relation to the femoral neck and within the confines of the acetabulum
slipped capital femoral epiphysis (SCFE)
pain and/or paresthesia in the anterolateral thigh associated with compression of lateral femoral cutaneous nerve
meralgia paresthetica
- lat femoral cut N gets compressed under inguinal ligament
what artery:
- runs posteriorly with the axillary nerve through the quadrangular space bounded by the teres minor and teres major muscles, the long head of the triceps brachii, and the humerus, around the surgical neck of the humerus
posterior humoral circumflex
IgM autoantibody against the fragment crystallizable (Fc) portion of IgG?
rheumatoid factor
- also look out for autoantibodies to mutated citrullinated vimentin (MCV) and anti-citrullinated peptide antibodies
when would you see prominent ulnar deviation of the digits?
RA
- a thoracic curvature of more than 50º results in compromise of what?
- while an angle of more than 75º will seriously compromise what?
50 -> respiratory function
75 -> CV
McMurray test for what?
meniscus
- also Apley grind test
pt supine
- flex the knee to 90° while the foot is held by the calcaneus with the other hand
- examiner then places one hand on the lateral side of the knee and externally rotates the leg while using valgus stress
medial meniscus -> McMurray
- lateral meniscus use internal rotation and varus stress
where does the ulnar collateral ligament attach?
from the inferior medial epicondyle (humerus) to the medial coronoid process (ulna)
young male w/leg pain and possible palpable mass
most often located in the metaphysis (distal femur) and usually has a rim of bone formation
- X-ray shows a sunburst pattern and Codman’s triangle
osteosarcoma
- MC primary bone tumor and is MC in adolescent boys
what muscle helps with knee flexion and hip extension?
biceps femoris
- long head innervated by tibial nerve
- short head innervated by common fibluar nerve
HLA-B8, DR3, DR4?
SLE
HLA-DQ2, DQ8?
dermatitis herpetiformis
HLA-B27? (4)
- Ankylosing spondylitis
- Reactive arthritis
- Psoriatic arthritis
- Inflammatory bowel disease-related arthritides
HLA-B51?
Behcet disease
- multisystem neutrophilic disease with a vasculitic component that is classically associated with recurrent oral and genital ulcerations, ocular abnormalities, and skin eruptions
HLA-Cw6?
psoriasis
Begin by monitoring the radial pulse of the ipsilateral arm that is being tested. The physician will extend that arm at the elbow, while simultaneously extending, externally rotating and slightly abducting the shoulder. The physician then asks the patient to take a deep inhalation and turn his/her head toward the ipsilateral arm. The test is positive if the radial pulse becomes markedly decreased or absent
Adson’s test -> thoracic outlet syndrome
ulnar deviation, boutonniere and swan-neck deformities?
RA
what two diseases have a weak transverse ligament of the atlas making HVLA contraindicated?
RA and Down’s
what increases the risk of a teenager developing osteosarcoma?
Childhood retinoblastoma
counternutation?
sacral base moves posteriorly
what is the MC SD in postpartum pts?
bilateral sacral flexion
what is the MC fractured bone of the midfoot?
navicular
- navicular is medial, cuboid is lateral
what nerve innervates the anterior compartment of the lower leg: tibialis anterior, extensor digitorum longus, and extensor hallucis longus.
deep peroneal (L4-S2)
what nerve innervates fibularis longus and brevis?
superficial peroneal
myotonia (noted with the sustained grasp), muscle wasting, frontal balding, cataracts, testicular atrophy, and arrhythmias
- CTG repeats
Myotonic muscular dystrophy (AD)
- anticipation occurs due to instability during maternal meiosis
postpubertal macroorchidism (large testes), long facies with a prominent jaw, large everted ears, autism, and cardiac defects most notably mitral valve prolapse - **CGG repeats** -> methylation of FMR1 gene
Fragile X syndrome (X-linked dominant)
- 2nd MC mental retardation after downs
staggering gait, numerous falls, nystagmus, dysarthria, pes cavus, hammer toes, hypertrophic cardiomyopathy, as well as childhood kyphoscoliosis
- impairment in mitochondrial function
- dysfunction within the spinal cord tracts leading to muscle weakness and loss of DTRs, vibratory sense, and proprioception
- frataxin gene mutation
Freidrich ataxia
- frataxin gene on xsome 9 = iron binding protein
what does calcium bind in skeletal muscle to initiate contraction?
- troponin*
- causes a conformational change in troponin -> tropomyosin exposes the myosin binding sites to actin
- myosin then binds actin causing conformational change
what muscles are responsible for finger abduction?
dorsal interossei
folic acid analog, which inhibits dihydrofolate reductase to decrease DNA expression
- used to treat severe rheumatoid arthritis, psoriasis, leukemia, lymphomas, and sarcomas
methotrexate
- liver enzymes should be tested regularly, can be hepatotoxic!
what does a positive drop arm test indicate?
supraspinatous tear
- after 90 degrees, the deltoid cannot maintain abduction without an intact supraspinatus
patient flexes the shoulder to 90 degrees and the elbow to 90 degrees, and the physician passively rotates the patient’s humerus into internal rotation. A positive test is when the patient experiences pain with the internal rotation
Hawkin’s test
- subacromial bursa impingement
disease-modifying antirheumatic drug (DMARD) that acts as a monoclonal antibody to tumor necrosis factor alpha (TNF-α)
- used to treat Crohn’s and RA
infliximab
- can get serious infections, so must do a PPD before starting tx to rule out latent TB
pts with with dermatomyositis are at increased risk of what?
interstitial lung disease
- can occur in up to 40% of patients with dermatomyositis
40-60 y/o woman
- difficulty with kneeling, climbing or descending stairs, raising arms, lifting objects, combing hair, and arising from a seated position
- labs reveal an elevated serum creatine kinase, lactate dehydrogenase, and aldolase
- cytotoxic T cell process against muscle fascicles
polymyositis
- anti-Jo Abs
- don’t confuse with MG! MG usually starts out eye drooping, worsens thruout day, alleviated by rest
pump handle motion ribs?
1-3
- ribs 4-5 are a combo
bucket handle motion ribs?
6-10
- ribs 11-12 are caliper
what commonly used diuretic can precipitate gouty arthritis flares?
thiazides
- inhibit NaCl transport in distal collecting tubule
how would you treat an acute gout flare?
- colchicine*, glucocorticoids, or anti-inflammatory
- allopurinol is for chronic gout
radiograph of the knee reveals a destructive, expansile lesion of the metaphysis of the distal femur with indistinct, irregular margins; a mixture of radiodense and radiolucent areas with radial ossification; and a reactive new periosteal bone formation
osteosarcoma
- look for elevated alkaline phosphatase, lactate dehydrogenase, and/or erythrocyte sedimentation rate
- radiodense/radiolucent = sunburst pattern
what is a Codman triangle, and when would you see it?
periosteal new bone formation
- osteosarcoma, Ewings
- Large, destructive, poorly marginated lesion with moth eaten appearance
- Characteristic periosteal deposition of layers of reactive bone causes an onion peel appearance.
- Often associated with a soft tissue mass
Ewing sarcoma
- diaphysis of long bones
- femur MC, then pelvis
- Fusiform expansion, mixed radiolucent and sclerotic appearance with areas of mineralized chondroid.
- atypical, hyperchromatic chondrocytes in lacunae with a surrounding chondroid matrix
- May have thickened cortex, but usually no periosteal reaction
- Most commonly proximal femur, pelvis, and proximal humerus
chondrosarcoma
- adults, usually 40-60’s
uncommon, benign bone lesion with a peak incidence in the second decade of life
- more common in boys, and accounts for 14% of benign bone lesions
- occurs in the spine, not the femur, and presents with chronic pain
osteoblastoma
what can be used as an alternative tx for osteoporosis to SERMs and bisphosphonates
- ex of post-menopausal woman with hx of DVT
calcitonin
- tones down blood calcium (PTH antagonist)
what ligament runs vertically over the apices of the spinous processes
supraspinous ligament
An injury to the midshaft of the humerus is most likely associated with what?
radial nerve palsy
- radial nerve crosses the humerus posteriorly in the spiral groove at the midpoint of the bone
- results in ‘wrist drop,’ an inability to extend the hand at the wrist as well as the fingers
what muscle initiates arm abduction for the first 15° of motion, and then the rest is assisted by the deltoid
supraspinatous
- injury -> positive drop arm test
- also Neer impingement test, Hawkins-Kennedy test, and Jobe’s test
anti–beta-2-glycoprotein I antibodies, anti-cardiolipin antibodies, and lupus anticoagulant
anti-phospholipid Abs
Recurrent pregnancy loss in a patient with SLE should prompt evaluation for what?
antiphopholipid Ab syndrome
- are at increased risk for thromboembolic events, which can result in fetal demise after 10 weeks, placental insufficiency, or repeat spontaneous pregnancy losses prior to 10 weeks of gestation age
joint pain in the absence of rheumatoid factor
- morning stiffness, fatigue, nail pitting, onycholysis
- HLA-B27
psoriatic arthritis
- other seronegative arthropathies include ankylosing spondylitis, Reiter’s syndrome
HLA-B8, B18, B27, B28, and C7
psoriatic arthritis
what is the primary tx for osteoporosis?
bisphosphonate such as alendronate, risedronate, or zoledronic acid
most common tumor that presents with back pain in children
- xray shows small radiolucent nidus
osteoid osteoma
exclusively in children under age 5, usually 2-3 y/o
- after a sudden upward force is applied to an outstretched, pronated arm
- pts will hold the arm in a slightly flexed and pronated position
radial head subluxation aka nursemaid’s elbow
- after age 5, the annular ligament is stabilized and thickened preventing further episodes of subluxation
medial elbow pain that affects the flexor mechanism of the patient’s wrist
medial epicondylitis aka golfer’s elbow
- Anterior innominate rotations are commonly caused by spasm or tightness in what muscle group?
- Posterior innominate rotations are associated with pain and somatic dysfunction of what muscle group?
anterior: ipsilateral quadriceps, esp retus femoris
posterior: ipsilateral hamstrings
radial subluxation of elbow in child under 5
- x-ray shows displacement of the radiocapitellar line
nursemaid elbow
- annular ligament not fully formed!
what is the mc tx for osteogenesis imperfecta type 1?
Risedronic acid (bisphosphonate)
labial biopsy will show lymphocytic infiltration of the minor salivary glands in the oral mucosa
Sjogren syndrome
- anti-Ro/La
presents in adolescence or early adulthood with exercise intolerance, fatigue, myalgia, cramps, poor endurance, muscle swelling, and fixed weakness
- all patients develop muscle stiffness, pain, and/or weakness that can be induced by either brief periods of intense isometric exercise (weight lifting) or by less intense but sustained dynamic exercise (running)
McArdle disease (glycogen storage disease [GSD] type V) - due to muscle phosphorylase deficiency
diagnosed early in childhood and will present with profound hypoglycemia due to impaired glycolysis and gluconeogenesis, and significant metabolic acidosis as *glucose-6-phosphate* accumulates and inhibits conversion of lactate to pyruvate • Enlarged kidney and liver • Slow growth • Very low blood sugar • High levels of acid, fats, uric acid
von Gierke disease
- glycogen storage type IA
- look out for second wind syndrome, where symptoms improve after about 10 minutes
Cobb angle < 20º ?
observe!
moderate scoliosis defined by a curvature between 20º and 45º
give a brace
when is surgery indicated for scoliosis?
typically > 45°—curves
what does a posterior fibular head cause?
- compression of the common peroneal nerve -> foot drop (plantar flexion)
- decreased sensation primarily on the dorsum of the foot and lateral leg
- weakness
what two muscles does the axillary nerve innervate?
teres minor and deltoid
what rotator cuff muscle is the primary external rotator?
infraspinatous
muscle contractions occur when a muscle shortens while generating force
- in relation to the elbow, the upward motion when performing a bicep curl
concentric contraction
muscle contractions occur when a muscle increases in length with contraction
- the muscle elongates while under tension due to opposing forces being greater than the force generated by the muscle, such as the lowering motion of a bicep curl
eccentric contraction
muscle contractions occur against resistance in which the angular change of joint motion is at the same rate (velocity). The counterforce is less than the patient’s force
isokinetic contraction
constant muscle tension as a muscle changes length (constant force)
- operator force is less than the patient’s force
isotonic contraction
- eccentric and concentric muscle contractions are two examples of isotonic contractions
a form of eccentric contraction where the counterforce is greater than the patient force
isolytic contraction
a muscle that is loaded and contracted in a rapid sequence. The short cycle affects the sensory response of the muscle spindles and golgi tendon organs; thus, increasing the excitatory threshold of the golgi tendon, which facilitates a greater contraction force than normal strengthening exercises.
pylometric contraction
sciatica can affect what muscles, besides piriformis?
posterior thigh hamstring muscles: semitendinosus, semimembranosus, and biceps femoris
- Piriformis syndrome can sometimes be confused with a hamstring strain, as sciatic nerve compression affects the hamstring muscles
middle age or elderly, hx of DM or shoulder immobilization
- thickening and contracture of the glenohumeral joint capsule which causes restrictions in all planes of motion, with external rotation and abduction most affected
adhesive capsulitis aka frozen shoulder
what nerve innervates short head of biceps femoris?
common fibular (branch of sciatic)
what nerve innervates long head of biceps femoris?
tibial branch of sciatic nerve
patients simultaneously exhibit signs of:
- SLE (rash and arthralgias, polymyositis including muscle weakness)
- systemic sclerosis including skin thickening and tightening
- also commonly have pulmonary involvement, including pulmonary effusions and interstitial lung disease
mixed connective tissue disease
- anti-ribonucleoprotein Ab
shoulder dystocia, MC injury?
Erb-Duchenne palsy
- injury to musculocutaneous nerve (C5-6, superior trunk, lateral cord)
what is the only muscle of the thenar eminence innervated by the ulnar nerve?
adductor policis (the rest are innervated by median nerve) - ulnar nerve helps with thumb adduction!
chronic inflammatory disease of the spine and sacroiliac joints that often leads to the stiffening or consolidation of the bones that make up the joints
- MC in men than women and typical onset is in the late teens and early twenties
- Xray shows bamboo spine
ankylosing spondylitis (HLA-B27)
- tx includes exercises to improve posture and indomethacin to relieve symptoms by reducing pain and decreasing inflammation
Ashkenazi jew w/diffuse bone pain
- Xray shows avascular necrosis of the femoral head
- anemia and thrombocytopenia result from splenic sequestration
- hepatosplenomegaly
- bx shows lipid-laden macrophages that have fibrillary cytoplasm look like wrinkled tissue paper
- PAS-positive
Gaucher disease (AR) - lysosomal storage disease, d/t a deficiency in glucocerebrosidase
two diseases with onion skinning
Ewing sarcoma and Tay-Sachs
what bone is broken in a Colle’s fracture?
distal radius
which nerve provides motor innervation to thenar muscles that include the opponens pollicis, abductor pollicis brevis, and flexor pollicis brevis?
median nerve
what NSAID can lead to gouty attacks?
aspirin
- both salicylic acid and uric acid compete for excretion in renal tubules
females over the age of 50
- myalgias and stiffness of the shoulder and hip girdle muscles after prolonged inactivity, especially upon awakening in the morning
- NO weakness, just pain
- normal creatine phosphokinase (CPK)
- elevated erythrocyte sedimentation rate (ESR) due to the synovitis, bursitis, and tenosynovitis that occurs in the joints
polymyalgia rheumatica
- tx: low-dose prednisone
what is polymyalgia rheumatica commonly associated with?
giant cell arteritis!
- look out for elderly female w/headaches and jaw claudication
what is the most common joint affected by septic arthritis?
knee
- fever, preexisting joint disease (RA), immunosuppression (DM, taking methotrexate, etc)
- septic arthritis spreads hematogenously
3-5 y/o with proximal muscle weakness
- pseudohypertrophy of the calf muscles
- present with a waddling, toe walking gait
- positive Grower’s sign (child uses his hands to walk up the legs from a seated position)
Duchenne muscular dystrophy (X-linked recessive)
- loss of dystrophin leads to myofibril membrane instability and degeneration of muscle fibers -> increased serum CK
- Becker MD is less severe form
inheritance of G6PD def?
X-linked recessive
inheritance of myotonic dystrophy?
AD
inheritance of fragile X?
X-linked dominant
lateral epicondyle pain associated with activities that involve grasping at the hand and twisting at the elbow, such as using a screwdriver or participating in racket sports
- affects wrist extensors (extending, supinating aggravates)
lateral epicondylitis aka tennis elbow
what is the order of humoral ossification centers?
shaft (ossifies in utero), then CRITOE
- capitellum
- radial head
- inner (medial epicondyle)
- trochlea
- olecranon
- external epicondyle
what artery supplies the levator scapulae muscle and rhomboids?
dorsal scapular A
what do serum Alkaline Phosphatase levels correlate with?
osteoBLAST activity
what is FGF23 a marker for?
abnormal phosphate metabolism
- is secreted in response to hyperphosphatemia
- lowers plasma phosphate by decreasing intestinal absorption
osteolytic bone lesions, hypercalcemia, anemia, AKI
multiple myeloma
- kidney injury results from lamba light chain nephropathy, where light chains accumulaate in the glomerulus causing tubular damage
