Musculoskeletal, Skin, and Connective Tissue Flashcards
Rotator cuff muscles
S - Supraspinatus (suprascapular nerve)
I - infraspinatus (suprascapular nerve)
t - teres minor (axillary nerve)
S - Subscapularis (upper and lower subscapular nerves)
Rotator cuff muscles - adduction
Teres minor (+ external rotation)
Subscapularis (+ internal rotation)
Hand muscles
Thenar (median)-
Opponens pollicis
Abductor pollicis brevis
Flexor pollicis brevis - superficial head (deep head by ulnar nerve).
Hypothenar (ulnar)
Opponens digiti minimi
Abductor digiti minimi
Flexor digiti minimi brevis.
Both groups perform the same functions: Oppose, Abduct, and Flex (OAF).
C5-T1 Nerves
Radial
Median
Recurrent branch of Median
Ulnar nerve roots
C8-T1
Recurrent branch of Median lesion
“Ape hand” (+ “Pope’s blessing” in lesion of median nerve) -> Loss of thenar muscle group: opposition, abduction, and flexion of the thumb
No loss of sensation (Loss of sensation over thenar eminence and dorsal and palmar aspects of lateral 3 1/2 fingers with proximal lesion of median)
Axillary nerve roots
(C5-C6)
Musculocutaneous
nerve roots
Upper trunk compression
C5-C7
Erb palsy
INJURY
MUSCLE DEFICIT
upper trunk:
C5-C6 roots
Deltoid, supraspinatus
lnfraspinatus
Biceps brachii
Klumpke palsy
INJURY
MUSCLE DEFICIT
lower trunk:
C5-T1 roots
Intrinsic hand muscles: lumbricals, interossei, thenar, hypothenar
Thoracic outlet
syndrome
INJURY
MUSCLE DEFICIT
Compression of lower trunk AND subclavian vessels, most commonly within the scalene triangle
Atrophy of intrinsic palsy hand muscles; ischemia, pain, and edema due to vascular compression.
Winged scapula
Lesion of long thoracic nerve, roots C5-C7 (“wings of heaven”)
“Clawing” - seen best with _____ lesions of median or ulnar nerves.
distal
Knee exam
Lateral femora l condyle to anterior tibia: ACL.
Medial femoral condyle to posterior tibia: PCL.
LAMP.
McMurray test
During flexion and extension of knee with rotation of tibia/foot (LIME):
• Pain, “popping” on internal rotation - Lateral meniscal tear (Internal rotation stresses lateral meniscus)
• Pain, “popping” on external rotation - Medial meniscal tear (External rotation stresses medial meniscus)
iliohypogastric - Nerve roots
Genitofemoral nerve - Nerve roots
Lateral femoral cutaneous - Nerve roots
iliohypogastric - (T12- L1)
Genitofemoral nerve - (L1-L2)
Lateral femoral cutaneous - (L2-L3)
Series
Obturator - Nerve roots
Femoral - Nerve roots
Obturator (L2-L4)
Femoral (L2-L4)
Same
Sciatic - Nerve roots
Common peroneal - Nerve roots
Tibial - Nerve roots
Sciatic (L4-S3)
Common peroneal (L4-S2)
Tibial {L4-S3)
One in the middle
lliohypogastric
Sensory-?
Motor-?
Sensory- suprapubic region
Motor- transversus abdominis and internal oblique
Genitofemoral nerve
Sensory-?
Motor-?
Sensory- scrotum/labia majora, medial thigh
Motor- cremaster
Lateral femoral cutaneous
Sensory-?
Sensory- anterior and lateral thigh
Obturator
Sensory-?
Motor-?
Sensory- medial thigh
Obturator externus G - gracilis A - adductor brevis A - adductor longus A - adductor magnus P - pectineus, adductor
Femoral
Sensory-?
Motor-?
Sensory- anterior thigh, medial leg
Motor- Q - quadriceps I - iliacus, P - pectineus Sr - sartorius
Sciatic
Motor-?
B - biceps femoris
A - adductor Magnus
S - semimembranosus
S - semitendinosus,
Common peroneal
Sensory-?
Motor-?
Superficial peroneal nerve:
• Sensory-dorsum of the foot (except web space between the hallux and 2nd digit)
• Motor-peroneus longus and brevis
Deep peroneal nerve:
• Sensory- web space between the hallux and 2nd digit
• Motor-tibialis anterior
Tibial
Sensory-?
Motor-?
Sensory- sole of foot
T - triceps surae I - 2- biceps femoris (long head) B I - 2- biceps femoris (long head) a l
Pope plants and flex - popliteus, plantaris, flexor muscles of the foot
Superior gluteal - Nerve roots
Inferior gluteal- Nerve roots
Pudendal - Nerve roots
Superior gluteal (L4-S1)
Inferior gluteal (L5-S2)
Pudendal (S2-S4)
Superior gluteal
Motor-?
Motor-
gluteus medius,
gluteus minimus
tensor fascia latae
Trendelenburg sign
Inferior gluteal
Motor-?
Motor- gluteus maximus
Pudendal
Sensory-?
Motor-?
Sensory- perineum
Motor- external urethral and anal sphincters
Abductors
Gluteus medius, gluteus minimus
Adductors
Adductor magnus, adductor longus, adductor brevis
Extensors
Gluteus maxi mus, semitend inosus, semimembranosus
MAX + SEMI
Flexors
S - sartorius T - tensor fascia lata R - rectus femoris I - Iliopsoas P - pectineus
Internal rotation
Gluteus medius, gluteus minimus, tensor fascia latae
External rotation
O - obturator
P - piriformis
I - Iliopsoas
G - gluteus maximus
Endochondral
ossification
Bones of axial skeleton, appendicular skeleton, and base of skull.
Cartilaginous model-> woven - > lamellar
Membranous
ossification
Bones of calvarium, facial bones, and clavicle.
woven - > lamellar
Osteoblast activity measured by
Osteoblastic activity measured by:
bone ALP
osteocalcin (mineralisaion)
propeptides of type I procollagen
Osteoclast
Dissolves (“crushes”) bone by secreting H+ and collagenases
RANK receptors
Carpal tunnel syndrome caused by:
D - diabetes
U - use (repetitive)
A - amyloidosis ( dialysis-related)
L - Lunate bone disslocation (acute)
T - thyroidism (hypo)
R - rheumatoid arthritis
A - acromegaly
P - pregnancy (due to edema)
Trochanteric bursitis
Inflammation of the gluteal tendon and bursa lateral to greater trochanter of femur.
“Unhappy triad”
damage to the ACL MCL, and medial meniscus (attached to MCL).
however, lateral meniscus involvement is more common
Prepatellar bursitis cause
pressure from excessive kneeling (a lso called “housemaid’s knee”).
Baker cyst
in gastrocnemius-semimembranosus bursa commonly communicating with synovial space and related to chronic joint disease (OA/RA)
DeQuervain tenosynovitis
Noninflaammatory thickening of abductor pollicis longus and extensor pollicis brevis tendons
Finkelstein test
risk in new mothers, golfers, racquet sport players.
Ganglion cyst
Fluid-filled swelling overlying joint or tendon sheath, most commonly at the dorsal side of wrist. Arises from herniation of dense connective tissue.
iliotibial band syndrome
friction of iliotibial band against lateral femo ral epicondyle.
Osteoporosis causes:
Most common: estrogen levels and old age.
other causes: C - coagulants (anti) A - alcohol M - malabsorption P - parathyroidism (hyper) S - steroids
T - thyroid replacement therapy e C -convulsants (anti) T - thyroidism (hyper) u M - multiple myeloma
Osteopetrosis
Failure of normal bone resorption due to defective osteoclasts - thickened, dense bones that are
prone to fracture.
pancytopenia, extramedullary hematopoiesis. It can result in cranial nerve impingement and palsies due to narrowed foramina.
Bone marrow transplant is potentially curative as osteoclasts are derived from monocytes.
Osteitis deformans
inc osteclastic activity followed by inc osteoblastic activity that forms poor-quality bone.
Avascular necrosis of bone
C - Corticosteroids A - Alcoholism S - Sickle cell disease T - Trauma S - SLE
Bend - “ the Bends” (caisson/decompress ion disease)
LE - LEgg-CalvePerthes
G - Gaucher disease
S - Slipped capital femoral epiphysis
Osteoarthritis
JOINT FINDINGS
TREATMENT
Osteophytes (bone spurs), joint space narrowing, subchondral sclerosis, and cysts. Synovial fluid noninflammatory (WBC < 2000/mm'}.
DIP
PIP
CMC
NOT MCP!
Heberden nodes,Bouchard nodes
Activity modification, acetaminophen, NSAIDs, intra-articular glucocorticoids.
Rheumatoid arthritis
JOINT FINDINGS
Erosions, juxta-articular osteopenia, soft tissue swelling, subchondral cysts, joint space narrowing. Deformities: cervical subluxation, ulnar finger deviation, swan neck, boutonniere.
MCP
PIP
wrist;
not DIP.
Synovial fluid inflammatory.
Rheumatoid arthritis TREATMENT
N - NSAIDs
o
G - glucocorticoids
oo
D - disease-modifying
H - hydroxychloroquine e L - leflunomide M - methotrexate e T - TNF-a inhibitors S - sulfasalazine
rheumatoid nodules
fibrinoid necrosis with palisading histiocytes - in subcutaneous tissue and lung
Caplan syndrome
pneumoconiosis + RA
Felty syndrome
interstitial lung disease, pleuritis, pericarditis, anemia of chronic disease, neutropenia + splenomegaly
Gout/Pseudogout Tx
Gout Tx
Acute: NSAIDs (eg, indomethacin), glucocorticoids, colchicine.
Chronic (preventive): xanthine oxidase inhibitors (eg, allopurinol, febuxostat).
Pseudogout Tx
Acute treatment: NSAIDs, colchicine, glucocorticoids.
Prophylaxis: colchicine.
Calcium pyrophosphate deposition disease associated with:
Usually idiopathic, sometimes associated with hemochromatosis, hyperparathyroidism, joint trauma.
Gout causes:
- Underexcretion of uric acid (90% of patients)- largely idiopathic, potentiated by renal failure; can be exacerbated by certain medications (eg, thiazide diuretics).
- Overproduction of uric acid (10% of patients)- Lesch-Nyhan syndrome, PRPP excess, t cell turnover (eg, tumor lysis syndrome), von Gierke disease.
Systemic juvenile idiopathic arthritis
Systemic arthritis seen in < 12 year olds. Usually presents with daily spiking fevers, salmon pink
macular rash, arthritis (commonly 2+ joints). Frequently presents with leukocytosis,
thrombocytosis, anemia, ESR, CRP.
give:
S - steroids o M - methotrexate T - TNF inhibitors h i N - NSAIDs
Systemic lupus
erythematosus
presents with:
RASH OR PAIN Rash (malar or discoid ) Arthritis (nonerosive) Serositis (eg, pleuritis, pericarditis) Hematologic disorders (eg, cytopenias)
Oral/nasopharyngeal ulcers (usually painless)
Renal disease
Photosensitivity
Antinuclear antibodies
Immunologic disorder (anti-dsDNA, anti-Sm, antiphospholipid)
Neurologic disorders (eg, seizures, psychosis)
Polymyositis/
dermatomyositis
labs
Nonspecific: ANA, inc. CK.
Specific: anti-Jo-I (histidyl-tRNA synthetase), anti-SRP (signal recognition particle), anti-Mi-2 (helicase).
Polymyositis
Progressive symmetric proximal muscle weakness, characterized by endomysial inflammation with CD8+ T cells. Most often involves shoulders.
Dermatomyositis
Clinically similar to polymyositis, but also involves:
Gottrnn papules
photo-distributed facial erythema (eg, heliotrope (violaceous] edema of the eyelids)
“shawl and face” rash.
darkening and thickening of fingertips and sides.
risk of occult malignancy.
Perimysial inflammation and atrophy with CD4+ T cells.
Diffuse scleroderma Associated with
anti-Scl-70 antibody (anti-DNA topoisomerase-1 antibody)
anti-RNA polymerase III
Epithelial cell junctions
TAD gap hemi
T - Tight junctions (zonula occludens) - claudins and occludins.
A - Adherens junction (belt desmosome, zonula adherens) - CADherins (Ca2+ dependent adhesion proteins). Loss of E-cadherin promotes metastasis.
D - Desmosome (spot desmosome, macula adherens) - structural support via intermediate filament
interactions
Gap - Gap junction - connexons
Hemidesmosmes - connects keratin in basal cells to the underlying basement membrane.
Hyperkeratosis
thickness of stratum corneum
Psoriasis, calluses
Parakeratosis
Retention of nuclei in stratum corneum
Psoriasis, actinic keratosis
Hypergranulosis
thickness of stratum granulosum
Lichen planus
Spongiosis
Epidermal accumulation of edematous fluid in intercellular spaces
Eczematous dermatitis
Acantholysis
Separation of epidermal cells
Pemphigus Vulgaris
Acanthosis
Epidermal hyperplasia (inc spinosum)
Acanthosis nigricans
Acne
sebum/androgen production
abnormal keratinocyte desquamation
Cutibacterium acnes colonization of the pilosebaceous unit (comedones), and inflammation.
Treatment: retinoids, benzoyl peroxide, and antibiotics.
Atopic dermatitis
eczema
Pruritic eruption, commonly on skin flexures.
Mutations in filaggrin gene predispose
Allergic contact dermatitis
Type IV hypersensitivity reaction secondary to contact allergen
Psoriasis
Acanthosis with parakeratotic scaling
Munro microabscesses.
Inc. stratum spinosum
Dec. stratum granulosum.
Auspitz sign - pinpoint bleeding spots from exposure of dermal papillae when scales are scraped off.
Associated with nail pitting and psoriatic arthritis.
Rosacea
An inflammatory facial skin disorder characterized by erythematous papules and pustules, but NO comedones.
Phymatous rosacea can cause rhinophyma.
Seborrheic keratosis
Flat, greasy, pigmented squamous epithelial proliferation of immature keratinocytes with keratin filled cysts (horn cysts)
Looks “stuck on.”
Leser-Trelat sign - indicates possible malignancy
Urticaria
Hives. Pruritic wheals that form after mast cell degranulation. Characterized by superficial dermal edema and lymphatic channel dilation.
Dermatitis herpetiformis Tx:
dapsone, gluten-free diet.
Erythema multiforme associated with infections:
P - phenytoin H - HSV o B - Beta lactams i S - sulfa drugs M - Mycoplasma pneumoniae
Nikolsky sign is present in:
Staphylococcal scalded skin syndrome - stratum granulosum
Pemphigus Vulgaris - stratum spinosum
Stevens-Johnson syndrome - dermal-epidermal junction
Acanthosis nigricans Associated with
insulin resistance (eg, diabetes, obesity Cushing syndrome, PCOS)
visceral malignancy (eg, gastric adenocarcinoma).
Erythema nodosum
Painful, raised inflammatory lesions of subcutaneous fat, associated with:
S - sarcoidosis
H - histoplasmosis
I - inflammatory bowel disease
T - TB
C - coccidioidomycosis
L - leprosy
S - streptococcal infections
Lichen Planus
Pruritic, Purple, Polygonal Planar Papules and Plaques are the 6 P’s
MucosaI involvement manifests as Wickham striae
Sawtooth infiltrate of lymphocytes at the dermal-epidermal junction.
Pityriasis rosea
“Herald patch”, followed days later by other scaly erythematous plaques, often in a “Christmas
tree” distribution on the trunk.
Multiple pink plaques with a collarette scale.
Self-resolving in 6-8 weeks.
Lichen Planus associated with_____
hepatitis C.
Keratoacanthoma
Seen in middle-aged and elderly individuals.
Rapidly growing, resembles squamous cell carcinoma. Presents as a dome-shaped nodule with a keratin-filled center.
Grows rapidly (4-6 weeks) and may spontaneously regress
Melanoma evaluation
Depth of tumor (Breslow thickness) correlates with the risk of metastasis.
Look for the ABCDEs: Asymmetry Border irregularity Color variation Diameter > 6 mm, Evolution over time.
Melanoma types
At least 4 different types of melanoma, including:
S - superficial spreading
L - lentigo maligna
A - acral lentiginous (highest prevalence in African-Americans and Asians)
N - nodular
