Musculoskeletal Flashcards by Jim Nino

What does genitofemoral nerve innervate?

Sensory: scrotum/labia majora
Motor: cremaster

How well did you know this?

Not at all

Perfectly

This provides sensory innervation to anterior and lateral thigh

Lateral femoral cutaneous (L2-L3)

How well did you know this?

Not at all

Perfectly

Genitofemoral nerve arises from what roots?

L1-L2

How well did you know this?

Not at all

Perfectly

This provides sensation to the medial thigh and motor input to obdurate externus, adductor longs, adductor breves, gracious, pettiness, and adductor magnus

Obturator nerve (L2-L4)

How well did you know this?

Not at all

Perfectly

This nerve provides sensory input to the anterior thigh and medial leg; motor innervation for quadriceps, iliacus, pectineus, sartorius

Femoral nerve (L2-L4)

How well did you know this?

Not at all

Perfectly

The sciatic nerve (L4-S3) innervates which muscles?

hamstrings (semitendinosus, semimembranosus, long and short head of bicep femoris) and adductor magnus

How well did you know this?

Not at all

Perfectly

The sciatic nerve continues down the posterior aspect of the thigh and splits into which 2 nerves?

Tibial nerves medially and common peroneal nerves laterally

How well did you know this?

Not at all

Perfectly

Common (fibular) peroneal nerve arises from what roots?

L4-S2

How well did you know this?

Not at all

Perfectly

Foot drop is caused by an injury to what nerve?

Common (fibular) peroneal nerve

How well did you know this?

Not at all

Perfectly

A patient who is unable to stand on tiptoes most likely injured what nerve?

Tibial nerve (L4-S3)

How well did you know this?

Not at all

Perfectly

What nerve roots does superior gluteal nerve arise?

(L4-S1)

How well did you know this?

Not at all

Perfectly

What does superior gluteal nerve innervate?

gluteus medius, gluteus minimus, tensor fascia latae

How well did you know this?

Not at all

Perfectly

A patient whose left hip tilts downward while walking has a lesion on what nerve?

Right superior gluteal nerve (Trendelenburg sign)

How well did you know this?

Not at all

Perfectly

A patient with right superior gluteal nerve injury will likely show pelvis tilt to which hip while standing?

Right

How well did you know this?

Not at all

Perfectly

What innervates gluteus Maximus?

inferior gluteal nerve (L5-S3)

How well did you know this?

Not at all

Perfectly

A patient with difficulty climbing stairs and standing from a sitting position likely injured what nerve and muscle?

inferior gluteal nerve and gluteus maximus

How well did you know this?

Not at all

Perfectly

This nerve provides sensation to the perineum and motor innervation to external urethral and anal sphincters

Pudendal (S2-S4)

How well did you know this?

Not at all

Perfectly

What nerve root is affected when a patient presents with weakness of knee extension and decreased patellar reflex?

How well did you know this?

Not at all

Perfectly

Weakness of dorsiflexion and difficulty in heel walking is a clinical finding of which injured nerve root?

How well did you know this?

Not at all

Perfectly

Weakness of plantar flexion, difficulty tip-toeing and decreased achilles reflex signifies what nerve root injury?

How well did you know this?

Not at all

Perfectly

In the sarcomere, which bands shorten?

H and I band

How well did you know this?

Not at all

Perfectly

Muscle spindle is activated by?

muscle stretch

How well did you know this?

Not at all

Perfectly

What type of sensory axon is associated with muscle spindle?

Type Ia and II

How well did you know this?

Not at all

Perfectly

Golgi tendon organ is stimulated by

increase in muscle force

How well did you know this?

Not at all

Perfectly

What type of sensory axon is associated with Golgi tendon organ?

Type Ib

what type of ossification is defective in achondroplasia?

endochondral ossification

This is a RANKL decoy receptor that binds RANKL therefore preventing RANK-RANKL interaction causing decrease in osteoclast activity

Osteoprotegerin (OPG)

How does estrogen protect bone?

estrogen inhibits apoptosis of osteoblasts while promoting osteoclast apoptosis

What is the protein activated that gives rise to achondroplasia and what is its mode of inheritance?

Fibroblast Growth Factor Receptor 3 (FGFR3). Achondroplasia is autosomal dominant (AD)

This protein inhibits chondrocyte proliferation

Fibroblast Growth Factor 3 (FGFR3)

This is a condition wherein there is loss of trabecular (spongy) and cortical bone lose mass despite normal bone mineralization

Osteoporosis

What is used in the treatment of osteoporosis?

Bisphosnates Teriparatide SERMs Denosumab (Monoclonal antibody against RANKL)

Entrapment of the median nerve in car tunnel causing paresthesia, pain, and numbness.

Carpal Tunnel Syndrome

What condition will bring about thenar eminence atrophy but spare sensation?

Carpal tunnel syndrome

Compression of the ulnar nerve at wrist. Classically seen in cyclists

Guyon canal syndrome

Clavicular fracture will result in what clinical manifestations?

Shoulder drop and shortened clavicle

Where is the weakest point of the clavicle and where does clavicular fracture occur most?

Weakest part is the junction between the middle and lateral 3rd. middle third is the most common site of fracture

What is the most common cause of osteomyelitis? In sexually actively? In patients with sickle cell? IV drug users?

S aureus N gonorrhea Salmonella Pseudomonas

Non inflammatory thickening of abductor pollicis longus and extensor pollicis brevis causing pain and tenderness at radial sryloid

De Quervain tenosynovitis

This is a common cause of shin pain and diffuse tenderness in runners caused by bone resorption that outpaces bone formation

Medial tibial stress syndrome (shin splints)

This is an idiopathic avascular necrosis of femoral head causing insidious onset of hip pain

Legg-Calve-Perthes disease

What is the mode of inheritance of achondroplasia?

AD with full penetrance

Failure of normal none resorption d/t defective osteoclasts causing thickened, dense bones that are prone to fracture

osteopetrosis

What is the mutation associated with osteopetrosis?

mutations that impair the ability of osteoclasts to generate acidic environment that is necessary for resorption (ie. Carbonic Anhydrase II)

Defective mineralization of osteoid or cartilaginous growth plates most commonly d/t vit D deficiency

Osteomalacia/Rickets

This is a disorder of bone remodeling caused by increased osteoclastic activity followed by increased osteoblastic activity causing formation of poor-quality bone

Osteitis deformans (Paget disease)

Hyperactivity of osteoblasts will show an increase in what lab value?

ALP

The lab values in Paget disease is expected to be:

normal Ca, PO4, and PTH

What pattern would you see in an X-ray of Paget disease?

mosaic pattern

Patients with osteitis deforming (Paget disease) will have an increased risk for formation of what malignancy?

osteosarcoma

What is the most common cause of death in patients with osteitis deforming (Paget disease)?

High output heart failure

What causes hearing loss in osteitis deforming (Paget disease)

narrowing of the auditory canal

Causes of avascular necrosis of bone

Corticosteroids, fx, sickle cell, Gaucher disease

Most common benign tumor of the bone that arises in metaphysis of long bones

Osteochondroma

Primary bone tumor that arises in the surface of facial bones and associated with Gardner syndrome

Osteoma

How can you differentiate osteoid osteoma from osteoblastoma?

osteoid osteoma < 2cm, responds to NSAIDS | osteblastoma >2 cm, does not respond to NSAIDS

This is the only bone tumor that arises in the epiphysis of long bones

Giant cell tumor

This is a malignant tumor of chondrocytes that are common in the medulla of the pelvis, proximal femur, and humerus

Chondrosarcoma

This is a bone malignancy where there is anapestic small blue cells of neuroectodermal origin and resemble lymphocytes

Ewing sarcoma

How can you differentiate Ewing sarcoma from lymphoma and osteomyelitis?

testing for t(11;22) fusion protein causing onion skin periosteal reaction of bone

What does rheumatoid factor in rheumatoid arthritis attack?

Rheumatoid factor - IgM antibody, targets Fc Region of IgG

How does OA presentation differ from RA

OA - asymmetric pain on weight bearing joints that improve with rest RA - pain, swelling, early morning stiffness, improved with use

Joint findings in OA and RA

OA - osteocytes deposit at PIP (Bouchard) and DIP (Heberden) RA - Pannus formation leads to Swan neck and Boutonnière deformity

Rheumatoid nodules (fibrinoid necrosis with palisading histiocytes) in sub Q and lung (pneumoconiosis)

Caplan syndrome

What condition can cause deposition of iron salts within the synovium that resembles OA?

Hemochromatosis

Needle shaped crystals that are (-) birefringent under polarized light that turns yellow

Gout

calcium pyrophosphate deposition disease (pseudo gout) is associated with what conditions?

hemochromatosis, hyperparathyroidism, joint trauma

Calcium pyrophosphate deposition disease while show what kind of crystals?

rhomboid (+) birefringent that turns blue under polarized light

What antibodies are positive in Sjogren syndrome?

RF, SS-A, SS-B

This is referred to as arthritis without rheumatoid factor (no anti-IgG antibody) and is associated with HLA B-27

Seronegative spodyloarthritis

What are the different types of seronegative spondyloarthritis?

Psoriatic arthritis Ankylosing spondylitis IBD Reactive arthritis

Sausage fingers associate with skin psoriasis and nail lesions

Psoriatic arthritis

Symmetric involvement/fusion of the spine and sacroiliac joins causing spondylitis, uveitis, aortitis (regurg). Clasically presents with bamboo spine in X-ray and may cause restrictive lung disease

ankylosing spondylitis

What is the triad seen in reactive arthritis?

Conjunctivitis, Urethritis, Arthritis | Can't see, can't pee, can't bend my knee

What are some bacterial causes of reactive arthritis?

Shigella, Yersinia, Chlamydia, Campylobacter, Salmonellla

What type of hypersensitivity is seen in SLE?

Type III hypersensitivity

An anti-SSA (+) pregnant woman has an increased risk for delivering a neonate with what cardiac problem?

congenital heart block

What are the nonspecific and specific markers for polymyositis and dermatomyositis?

Nonspecific: CK, ANA Specific: Anti-Jo-1 (histidyl-tRNA synthetase) Anti-SRP (signal recognition particle) Anti-Mi-2 (helicase)

Progressive symmetrical proximal muscle weakness, characterized by ENDOMYSIAL inflammation with CD8 T cells often involving the shoulders

Polymyositis

This is similar to polymyositis but also involves Grotton papules, PERIMYSIAL inflammation in shawl and face distribution, increased risk for occult malignancy, and involvement of CD4 T cells

dermatomyositis

This is a degenerative d/o characterized by muscle wasting resulting from replacement of skeletal muscle by adipose tissue

X-Linked Muscular Dystrophy (Duchenne Muscular Dystrophy)

Duchenne Muscular Dystrophy is d/t deletion of what gene?

Dystrophin (largest gene in human genome and anchors muscle cytoskeleton to the ECM)

Differentiate pathophysiology of Myasthenia Gravis from Lambert-Eaton Myasthenic Syndrome

Autoantibodies compete with ACh in postsynaptic ACh receptors in MG. Lambert-Eaton has autoantibodies to presynaptic Ca channels --> decreased ACh release