Diseases for MSK Module Exam

A 42-year old woman presents with fever, fatigue, and persistent productive cough for the past three weeks. Chest x-ray shows a cavitary lesion in the upper lobe of the right lung. She takes several medications, including hydrochlorothiazide for blood pressure and etanercept for psoriatic arthritis. What is the most likely diagnosis? A) interstitial lung disease B) S. pneumoniae infection C) coccidioidomycosis infection D) reactivated tuberculosis infection E) Pseudomonas infection

D) reactivated tuberculosis infection etanercept is a TNF-a inhibitor, and TNF-a inhibitors can reactivate TB as TNF-a is essential for TB granuloma formation also cavitary lesion in upper lobe is a dead giveaway for TB rather than another infection

what ligaments/structures must be punctured during a CSF lumabr tap?

CSF is in the subarachanoid space must puncture supraspinous ligament, infraspinous ligament, ligamentum flavum, dura mater, and arachanoid mater

Pseudogout (pathogenesis and treatment)

Calcium pyrophosphate deposition in joints leads to pain rhomboid, weakly positive birefringent crystals Mostly older pts, seen equally in both genders treatment = NSAIDs, colchicine

Presentation: numbness, tingling, and weakness of medial palm of hand; atrophy of thenar muscles, Tests: positive Tinel Sign, positive Phalen maneuver, sensation of palm still present History: pregnancy, diabetes, hypothyroidism, repetitive use

Carpal tunnel syndrome (case) (Tinel sign = tapping on wrist --> tingling Phalen maneuver = 90 degree flexion of wrist --> pain)

Presentation: shoulder drop, limited mobility of the shoulder History: fall on outstretch shoulder (FOOSH), neonatal

Clavicular fracture fractures at middle third segment is most common often fractured in children as trauma during childbirth

Guyon's canal syndrome (pathogenesis)

Compression of the ulnar nerve between the pisiform & the hook of the hamate. Cyclists may put pressure on this area with their handlebars (cyclists/handlebar neuropathy). Often associated with fracture of hamate bone.

An 8 year old boy presents with asymmetric pain in multiple joints. He is uncooperative at physical exam, but you are able to notice multiple scars and scratches, which his mother states are "self-inflicted". What is the most likely cause of the patient's joint pain? A) child abuse B) osteoarthritis C) rheumatoid arthritis D) gout E) Ricketts

D) gout The presentation seems to lead towards the child having Lesch-Nyan's disease, which is associated with mental retardation, self-destructive behavior, and gout, which likely caused the joint pain.

A 43-year old woman presents with painful oral ulcers. Two weeks ago, she came into the clinic with bilateral, inflammatory joint pain of her hands and was prescribed medication to treat her condition. What is the most likely reason for her oral ulcers? A) complication of her inflammatory joint pain B) systemic lupus erythematosus C) herpes simplex virus 2 D) side effect of her joint pain medication E) oral hairy leukoplakia

D) side effect of her joint pain medication The patient most likely had rheumatoid arthritis and was prescribed methotrexate. A side effect of methotrexate is mucositis, which presents as painful oral ulcers.

Klumpke palsy (pathogenesis)

Injury to lower trunk: C8-T1 roots this will affect the ulnar nerve (C8-T1), which supplies the deep intrinsic hand muscles, like lumbricals and interossei loss of the lumbricals leads to claw hand (lumbricals usually flex MCP and extend DIP & PIP)

Presentation: claw hand (flexion of DIPs and PIPs, extension of MCP) History: infants = upward force on arm during delivery, adults = trauma (grabbing tree branch on fall)

Klumpke palsy

An 8-year-old boy with a history of ADHD is admitted to the emergency department with severe hip pain. Physical exam reveals a positive Trendelenburg gait and decrease ROM of the hip. Imaging reveals thickening of the femoral neck. What is the most likely diagnosis?

Legg-Calve-Perthes disease

presentation (usually a child, thin and hyperactive): limp, hip or knee pain physical exam: decreased hip ROM, positive Trendelenburg gait, positive logroll test Imaging: may see thickening of femoral neck

Legg-Calve-Perthes disease

for RA, there are two main autoantibodies. Name them, and tell me which is more specific and which is more sensitive.

anti-cyclic citrullinated peptide (anti-CCP): specific rheumatoid factor: sensitive

In a fractured surgical neck of humerus or dislocation of humeral head, what is the possible nerve injury, motor deficit, sensory deficit?

axillary nerve (posterior circumflex humeral artery also gets injured) motor deficit = loss of arm abduction from 15-100 degrees sensory deficit over lateral deltoid & arm

presentation: flattened deltoid, loss of arm abduction, loss of sensation over lateral deltoid & arm

axillary nerve (C5-C6) injury

Legg-Calve-Perthes Disease (pathogenesis and treatment)

degeneration of the femoral head due to avascular necrosis with no specific cause. Incidence is 1 in 10,000 presents with pain, decreased ROM, antalgic gait, positive Trendelenburg sign. primary treatment focus is to relieve pain and maintain femoral head in proper position (containment). - NSAIDs, activity modification, abduction braces - older kids/severe: surgery = femoral or pelvic osteotomy

A 55-year old man presents with joint pain of the right knee. Physical exam reveals psoriaform lesions on the plantar aspect of the patient's feet. Labs are negative for rheumatoid factor and ANA. The patient denies fever, chills, or nausea. He has no other remarkable dermatological features elsewhere on his body. What is the most likely diagnosis? A) reactive arthritis B) septic arthritis C) psoriatic arthritis D) ankylosing spondylitis E) gout

reactive arthritis keratoderma blennorhagicum

Osteogenesis imperfecta (pathogenesis)

results from a defect in type 1 collagen deposition (COL1A1 and COL1A2 gene mutations), leading to brittle bones - autosomal dominant - pathologic fractures, brittle bones, deafness, tooth abnormalities, blue sclera - tooth abnormalities due to lack of dentin = dentinogenesis imperfecta - often confused with child abuse treatment = bisphosphonates

presentation: pain & swelling of joints (usually symmetric & polyarticular), morning stiffness >1 hour, pain improves with movement/worsens with rest, systemic symptoms (fever, fatigue, weight loss), swan neck & boutonniere deformity, ulnar finger deviation + radial wrist deviation Radiograph: erosions and osteopenia, subchondral cyst, joint narrowing labs: elevated ESR & CRP, joint fluid WBC >2000 but <50,000, possibly positive anti-CCP antibody and rheumatoid factor genetics: HLA DR4 pertinent negatives: usually no DIP involvement

rheumatoid arthritis

presentation: shoulder pain, worse with flexion/abduction overhead activities or lying down on affected shoulder. physical exam: positive empty can test

rotator cuff tendonitis, specifically of supraspinatus MRI used to confirm diagnosis treatment: RICE, NSAIDs, steroid injections

presentation: numbness, tingling, or weakness in back, buttocks, back of lower leg physical exam: straight leg test positive history: osteoarthritis, herniated disc, spinal stenosis, spondylolisthesis, piriformis syndrome

sciatica (lumbar radiculopathy) herniated disc or stenosis can cause pinching of the sciatic nerve, leading to these symptoms

Presentation (in infants): paralysis of lower limbs, bladder and bowel incontinence, higher risk of infection during pregnancy: folate deficiency, diabetic labs: increased a-fetoprotein (sometimes), increased AchE in amniotic fluid

spina bifida

Presentation: pain, numbness, or weakness in back or lower extremities; bladder or bowel dysfunction history: ostoearthritis leaning forward may relieve symptoms

spinal stenosis

presentation: often asymptomatic, but can present with stiffness, low back pain, and waddling gait

spondylolisthesis

presentation: sometimes asymptomatic, but usually low back pain history: athletes like gymnast (repetitive hyperextension); or, could just be old x-ray: scottie dog sign

spondylolysis

Spondylolysis and Spondylolisthesis (pathogenesis)

spondylolysis is a defect/fracture in pars interarticularis; spondylolisthesis is a slippage of one vertebra compared to another (often L5/S1 junction), sometimes caused by spondylolysis.

In what space is the cerebrospinal fluid located?

subarachnoid space

spinal complication of rheumatoid arthritis

subluxation of cervical spine (C1-C2 joint) - can lead to spinal cord or brainstem compression serious complication!

Which rotator cuff muscle is most commonly injured?

supraspinatus

lateral epicondylitis (tennis elbow) (pathogenesis and treatment)

tendinosis of the common extensor tendon due to overuse of extensor muscles, especially in sports with repetitive backhand motions (like tennis). Treatment: NSAIDs, steroids, botox, surgery

osteomalacia/rickets histology (this isn't really a question, just know what the histology looks like)

thicker than normal trabeculae (osteoid)

Fracture of medial epicondyle of humerus will injure which nerve? What will be the motor/sensory deficits?

ulnar nerve "ulnar claw" on digit extension decreased flexion of ulnar fingers, abduction & adduction of the fingers (interossei), thumb adduction Loss of sensation over medial 1.5 fingers - fractured hook of hamate can also cause ulnar nerve injury

Erb-Duchenne palsy (pathogenesis)

(I gave a really detailed explanation, probably more in-depth than what we need to know) Superior trunk brachial plexus injury ("waiter's tip") - the superior trunk takes from roots from C5-C6, so any nerve off of the superior trunk or that is mostly C5 & C6 will be affected - the nerves that are injured are the suprascapular nerve, musculocutaneous nerve (C5-C7), and axillary nerve (C5-C6) - suprascapular nerve supplies infraspinatus and supraspinatus. Supraspinatus is involved in abduction, infraspinatus is involved in lateral rotation. - musculocutaneous nerve supplies biceps brachii & brachialis, which does supination & arm flexion. - axillary nerve supplies deltoid and teres minor. Deltoid does abduction, teres minor does lateral rotation So let's now go through the symptoms of Erb palsy - adduction of arm = lack of abduction from loss of fxn of supraspinatus and deltoid - medial rotation of arm = lack of lateral rotation from loss of fxn of infraspinatus and teres minor - pronation & extension of arm = lack of supination from biceps brachii, lack of flexion from brachialis & biceps

Paget disease of bone (osteitis deformans) (pathogenesis and treatment)

- Common idiopathic alteration of bone exhibiting abnormal resorption and deposition, resulting in distorted and weakened bones - Will have bone pain, fractures, hearing loss, change in hat size - normal labs except increased ALP - Increased risk of osteosarcoma Treatment: bisphosphonates

rheumatoid arthritis (pathogenesis and treatment)

- a chronic autoimmune disorder in which the joints and some organs of other body systems are attacked - often associated with TNF-a, IL-17 and IL-22, leading to synovitis and formation of a pannus (proliferative granulation disease), which erodes articular cartilage and bone - risk factors: women, smokers, HLA-DR4 - treatment: NSAIDs, glucocorticoids, methotrexate, leflunomide, TNF-a inhibitors

Osteopetrosis (pathogenesis and treatment)

- abnormal condition of stonelike bones (marblelike bones) caused by defective osteoclast resorption of bone (due to mutations, like carbonic anhydrase II deficiency). - can be autosomal recessive (severe) or autosomal dominant (less severe) - can result in cranial nerve impingement --> vision and hearing loss Treatment: None, but maybe bone marrow transplant (osteoclasts are derived from HSCs)

Gout vs pseudogout - how to tell difference on physical exam?

- gout usually affects the big toe (podagra) while pseudogout usually affects the knee. - gout affects men more than women; pseudogout is not sexist - gout is associated with alcoholism, tumor lysis, Lesch-Nyan while pseudogout is not.

osteoporosis (pathogenesis and treatment)

- most common metabolic abnormality of bone - The rate of bone resorption accelerates and the rate of bone formation decelerates - Decreased density and loss of trabeculae - A reduction in bone mass predisposes to fractures (brittle, porous bones) - DEXA scan to diagnose (<-2.5) - Treatment: bisphosphonates (alendronate), estrogen replacement - side effect of bisphosphonates = erosive esophagitis (leads to burning chest pain)

A 48-year old woman presents with joint pain present in both hands. Physical exam reveals deformities of the left hand, with radial deviation of the wrist and ulnar deviation of the fingers. The left second, third, and fifth digits also show hyperextension at the proximal interphalangeal joint and flexion at the distal interphalangeal joint. 1) What is the term for the deformity of the fingers in the patient? 2) What is the most likely diagnosis?

1) swan neck deformity 2) rheumatoid arthritis

A 2-week old girl presents with decreased right hip range of motion. During physical exam, the physician manipulates the right hip. Adduction of the leg with a posterior force leads to dislocation, while abduction of the leg with an anterior force leads to a "clunking" sound. 1) What are the names the two maneuvers performed on the patient? 2) What differential diagnosis is most likely given the presentation and physical exam? 3) What imaging would be best to confirm the diagnosis? 4) If the differential diagnosis is confirmed, what is the best way to treat the patient?

1) the first is the Barlow maneuver, the second is the Ortolani maneuver 2) Positive Barlow and Ortolani maneuvers are signs of developmental dysplasia of the hip 3) For infants, dynamic ultrasound is best to diagnose hip dysplasia 4) For infants (<4-6 months), a Pavlik harness is the best treatment for developmental hip dysplasia.

A 53-year-old obese man presents with pain in the feet and hands. On exam, you notice an erythematous, swollen right first MTP and swelling in the left second MCP. A crystal analysis of the affected joints would most likely yield what? A) needle-like crystals, yellow when parallel to light and blue when perpendicular. B) needle-like crystals, blue when parallel to light and yellow when perpendicular. C) rhombus-shaped crystals, yellow when parallel to light and blue when perpendicular. D) rhombus-shaped crystals, blue when parallel to light and yellow when perpendicular. E) no crystals at all.

A) needle-like crystals, yellow when parallel to light and blue when perpendicular. This presentation is consistent with gout, which is strongly negatively birefringent (yellow when parallel, blue when perpendicular) with needle-like crystals.

A 12 year old obese child presents with hip and groin pain for 3 months duration. Radiograph analysis reveals anterior displacement of the femoral metaphysis compared to the epiphysis. Physical exam is likely to show which of the following findings? A) obligate external rotation of the thigh B) obligate internal rotation of the thigh C) tibial bowing D) pes planovalgus E) lack of Trendelenburg gait

A) obligate external rotation of the thigh The history (obese child w/ hip/groin pain) and radiograph analysis is consistent with SCFE. One finding of SCFE is obligate external rotation of the thigh (Drehmann sign). B is wrong; SCFE will have lack of internal rotation C and D are not associated with SCFE. E is wrong; SCFE will be positive for Trendelenburg gait

A 46-year-old woman comes to the clinic for pain and swelling of the joints in her hands and feet for the past few years. Her pain is associated with stiffness and is worse for the first hour in the morning. These symptoms interfere with common household tasks. On physical examination, she has symmetric swelling of the joints of her hands and feet. What is the most likely diagnosis? A) rheumatoid arthritis B) osteoarthritis C) reactive arthritis D) psoriatic arthritis E) septic arthritis

A) rheumatoid arthritis

A 43-year-old woman presents with pain and numbness of the lateral side of her left palm. She complains of waking up in the night and "shaking out her hand" to relieve her symptoms. Surgical incision to which ligament may provide relief to the patient's symptoms? A) transverse carpal ligament B) extensor retinaculum C) scapholunate ligament D) Triangular fibrocartilage complex E) Annular Ligament

A) transverse carpal ligament This is the same thing as the flexor retinaculum The patient has carpal tunnel syndrome, so surgery to transverse carpal ligament may free the median nerve and relieve symptoms. "shaking out the hand" in the middle of the night is a classic symptom of carpal tunnel syndrome.

Presentation: tibial bowing, shortened arms/legs, macrocephaly (in comparison, actually normal sized head), normal intellect Labs: normal growth hormone, normal IFG-1 levels history: advanced paternal age during birth

Achondroplasia

A 14-year-old child presents with limp and groin pain for 2 months duration. Physical exam shows obligate external rotation of the thigh, decreased internal rotation of the thigh, and a Trendelenburg gait. The child's BMI is 35. Radiograph analysis would most likely reveal which of the following? A) femoral epiphysis osteonecrosis and chondronecrosis B) anterior displacement of the femoral metaphysis compared to the epiphysis C) bilateral sclerosis of the sacroiliac joint D) tibial bowing, along with osteopenia and pseudofractures of the tibia

B) anterior displacement of the femoral metaphysis compared to the epiphysis The case is describing SCFE, and B is the explanation of what happens in SCRE A is talking about Legg-Calves Perthes disease C is some BS I made up D is talking about osteomalacia/ricketts

A 50-year old man presents with weakness and pain of his right thumb. He complains that he is not able to grasp simple objects. Physical exam shows compromised opposition and abduction of the thumb, along with atrophy of thumb muscles. What is the diagnosis? A) Guyon canal syndrome B) Carpal tunnel syndrome C) Anterior interosseous syndrome D) Anterior compartment syndrome E) Medial epicondylitis

B) carpal tunnel syndrome Recurrent branch of median nerve supplies thenar (thumb) muscles like opponens pollicis and abductor pollicis. Pressure on the median nerve in carpal tunnel can lead to weakness/atrophy of thenar muscles.

A 35-year-old woman presents with knee pain for the past four months. The pain is present in both of her knees. Radiograph shows joint space narrowing and soft tissue swelling. Ultrasound reveals increased synovial fluid in the knee joint, and a right knee arthrocentesis is performed, yielding the following results: WBCs: 35,000 PMNs: 59% Crystal analysis: negative What is the most likely diagnosis? A) osteoarthritis B) rheumatoid arthritis C) reactive arthritis D) septic arthritis E) psoriatic arthritis

B) rheumatoid arthritis (with this presentation, both reactive and psoriatic arthritis are also technically possible. But, with no history of infection or psoriasis, along with RA being more common than both, RA is more likely)

A 64-year-old woman presents with shortened stature and kyphosis. She states she has been feeling weakness in her bones for the past 5 years. She has a history of multiple fractures over the past 7 years. What would be the best test to order for a definitive diagnosis? A) MRI B) CT scan C) DEXA scan D) Arterial Blood Gas (ABG) E) Ultrasound

C) DEXA scan patient is presenting with signs of osteoporosis, which is diagnosis using a DEXA bone density scan.

A 3-year-old boy is brought to the clinic by his parents. His parents state that he hasn't been responding to commands and are concerned about a developmental delay. Physical exam shows that the boy passes all developmental milestones for his age, but is suffering from hearing loss. Past medical history shows three emergency room visits in the past year for fractures without any trauma. The father states that he also had several fractures as a child, and recently visited the dentist for several broken teeth. What is the best plan of action for the child's condition? A) Conduct screening for autism B) Contact child protective services and report child abuse C) Genetic testing for a collagen synthesis defect, then start physical therapy and possibly bisphosphonates D) Refer to a pediatric orthopedic surgeon for correction of developmental hip dysplasia

C) Genetic testing for a collagen synthesis defect, then start physical therapy and possibly bisphophonates The CC of hearing loss along with the history of fractures, along with the dad's history shows a possibility of type 1 osteogenesis imperfecta. OI is caused by a collagen synthesis defect, and treatment for it includes physical therapy to decrease fracture frequency along with bisphophonates. A is wrong, no signs of autism B is wrong. OI is often confused with child abuse, but the family history points more towards OI. D is wrong, developmental hip dysplasia has nothing to do with this

A 24-year-old man presents with a large, erythematous swelling over his left patella. He states he had been thoroughly cleaning his apartment over the past two days. The swelling is painful when touched, and flexion of the knee is compromised. He denies any fever or chills. The swelling is most likely due to inflammation of the A) patellar tendon B) quadriceps tendon C) prepatellar bursa D) anterior cruciate ligament (ACL) E) infrapatellar bursa E) fibular collateral ligament

C) prepatellar bursa most likely this is housemaid's knee.

A 55-year-old woman presents with thoracic curvature and shortened stature. She has a history of multiple fractures over the past 7 years, including a Colles fracture. A medication is prescribed by her physician to help in her condition. What is the likely mechanism of action of the medication? A) dihydrofolate reductase inhibitor to decrease pyrimidine synthesis B) selective COX2 inhibitor that inhibits prostaglandin synthesis C) pyrophosphate analog that inhibits osteoclast activity D) xanthine oxidase inhibitor to prevent uric acid crystalization E) inhibition of ribonucleotide reductase to prevent deoxypyrimidine synthesis

C) pyrophosphate analog that inhibits osteoclast activity The patient has osteoporosis, which is often treated with bisphosphonates. A is methotrexate B is celecoxib C is bisphosphonates D is allopurinol E is hydroxyurea

A 55-year old man presents with painful urination and discharge from the penis. On further questioning, he reveals he has also began to have joint pain in his right knee. He had traveled to Nicaragua a month prior. He is sexual active but claims to be using protection during sex. Gram stain of the urine and joint fluid is negative. What is the most likely diagnosis for the patient's current symptoms? A) C. trachomatis infection B) N. gonnorhea infection C) reactive arthritis D) E. coli infection E) rheumatoid arthritis

C) reactive arthritis

Osteomalacia/rickets (pathogenesis)

Defective mineralization of osteoid (osteomalacia) or cartilaginous growth plates (rickets, only in children). Most commonly due to vitamin D deficiency Labs will show low vitamin D, low calcium, low phosphate, high PTH, high ALP

presentation (in babies or young kids): decreased hip range of motion, asymmetric abduction of hip, limp or waddling gait history: breech baby, female, firstborn physical exam: positive apparent leg length discrepancy (Galeazzi sign), positive Barlow and Ortolani signs

Developmental dysplasia of the hip

A 50-year-old man presents with bone pain and a waddling gait. The bone pain is dull and widespread and affects his hips, back, and lower legs. The man states he works in a coal mine; he begins work before sunrise and leaves the mine after sunset, rarely coming out of the mine during the day. He is also lactose intolerant and therefore avoids milk and other dairy products. What is the most likely diagnosis, and what is the best treatment course?

Diagnosis is osteomalacia, treatment is vitamin D since he doesn't get sunlight and doesn't drink milk, he probably has severe vitamin D deficiency, leading to osteomalacia.

A 2-month old boy presents with tibial bowing. Physical exam reveals a protruding sternum along with expansion of the anterior rib ends at the costochondral junctions. What is the most likely diagnosis, and what is the best treatment course?

Diagnosis is rickets, treatment is vitamin D supplementation protruding sternum = pigeon breast expansion of the anterior rib ends at the costochondral junctions = rachitic rosary

A 36-year old woman presents with joint pain in both of her hands. The pain mostly involves the DIPs of both hands with slight PIP involvement. Physical exam shows dactylitis and nail pitting bilaterally. What is the most likely diagnosis? A) osteoarthritis B) rheumatoid arthritis C) reactive arthritis D) septic arthritis E) psoriatic arthritis

E) psoriatic arthritis Psoriatic arthritis doesn't have to always have psoriasis Psoriatic arthritis is one of the few inflammatory arthritides that involves the DIPs Dactylitis and nail pitting are also big clues for PSA

Presentation: arm drawn in adduction, medial rotation; arm is extended and pronated; wrist is extended; defect in abduction, lateral rotation, pronation, and supination (waiter's tip arm) History: maybe in neonatal baby (lateral traction on neck during delivery) or adult after trauma (like a fall on top of the arm)

Erb-Duchenne palsy

presentation: rheumatoid arthritis, pancytopenia, splenomegaly

Felty syndrome

Presentation: pain, red, & swelling in joint (often big toe), asymmetrical, deposits around joints, usually older male Labs: hyperuriciemia (although uric acid can be normal in acute attacks), negative birefringent crystals

Gout (case) deposits around joints = tophus pain/swelling in big toe = podagra

A 23-year-old man presents with a loss of sensation on the medial side of his right hand. He is an avid cyclist. Physical exam reveals weakness in flexion at the MCP and weakness in adduction and abduction of the digits. What is the diagnosis?

Guyon canal syndrome

Presentation: partial loss of sensation (hypoesthesia), weakness of intrinsic hand muscles (lumbricals, interosseous muscles) History: cyclist

Guyon canal syndrome

Achondroplasia (pathogenesis)

Mutation in fibroblast growth factor receptor-3 (FGFR-3) gene, leading to its constitutive activation --> impaired chondrocyte proliferation and cartilage at growth plate. - most common cause of short limb dwarfism - autosomal dominant w/ 100% penetrance (homozygosity is lethal) No treatment

presentation: young child (<5 year old) with injured arm held in slightly flexed and pronated position

Nursemaid's elbow sudden pull on the arm -->sublaxation of radial head from annular ligament

Presentation: pathologic fractures, brittle bones, deafness, tooth abnormalities, blue sclera

Osteogenesis imperfecta

A 8-month old boy presents with an arm fracture. This is the fourth fracture the child has had since birth. Physical exam is remarkable for a bluish pigmentation to the eye. What is the most likely diagnosis?

Osteogenesis imperfecta.

Presentation: diffuse bone pain, muscle weakness, waddling gait, genu varum (bowlegs). Labs: low vitamin D, low calcium, low phosphate, high PTH, high ALP History: adult

Osteomalacia

A 2-month-old girl presents with fever, failure to thrive, and nasal stuffiness. The physical exam is remarkable for an increase in head circumference. CBC shows low RBCs and hemoglobin, along with normal calcium and phosphate. What is the likely diagnosis?

Osteopetrosis nasal stuffiness due to paranasal/mastoid malformations

Presentation: several fractures, visual/hearing loss, nasal stuffiness (paranasal/mastoid malformations), hepatosplenomegaly Labs: anemia, pancytopenia, carbonic anhydrase II deficiency, extramedullary hematopoeisis, normal (Ca)2+, (PO4)3-, ALP, & PTH (although Ca may be low in severe disease) X-ray will show systemic sclerosis

Osteopetrosis (marble bone disease)

Presentation: loss of stature, Dowager's hump (kyphosis), multiple fractures, colles fracture of distal radius Labs: decreases estrogen in women; normal (Ca)2+, (PO4)3-, ALP, & PTH; DEXA score of <-2.5, History: old age, post-menopausal, hypercortisolism (Cushing's), malnutrition, hypogonadism

Osteoporosis (case)

A 72-year-old man complains of left hip pain for several months duration. Physical exam reveals reduced range of motion in both hips. Radiographs of the pelvis demonstrate sclerotic, thickened cortical bone with joint space narrowing near the acetabulum. Further questioning reveals that the patient cycles every day, and recently he had to change his helmet because his previous one became too small. Labs reveal a serum alkaline phosphate of 190 U/L, calcium of 9.6 mg/dL, and phosphorus of 3.7 mg/dL. What is the most likely diagnosis?

Paget Disease of Bone (osteitis deformans)

Presentation: bone pain, headaches, hearing loss, fractures, high output heart failure, Labs: increased ALP, normal calcium, phosphorus, and PTH May see a change in hat size

Paget Disease of Bone (osteitis deformans)

Presentation: asymmetric pain in joint (usually knee) Labs: no hyperuricemia, x-ray may show cartilage calcification (chondrocalcinosis), sometimes hyperparathyroidism

Pseudogout (calcium pyrophosphate deposition disease)

Presentation: short stature, genu varum, tetany, soft skull (craniotabes), bead-like costochondral junctions (rachitic rosary), pigeon breast Labs: low vitamin D, low calcium, low phosphate, high PTH, high ALP X-ray will show osteopenia and pseudofractures, metaphyseal cupping History: child

Ricketts

presentation: wrist drop, decreased grip strength, loss of sensation over posterior arm/forearm History: sleeping on arm over a chair

Saturday Night Palsy radial nerve injury

herniated disc (slipped disc)

Usually caused by heavy lifting. Anulus fibrosus ruptures, allowing nucleus pulposis to protrude. Puts pressure on spinal nerve roots causing pain - sometimes leads to sciatica --> leg pain and numbness - can also cause cauda equina treatment: heat, pain killers, physical therapy, surgery (microdiscectomy)

spina bifida

a congenital defect that occurs during early pregnancy when the spinal canal fails to close completely around the spinal cord to protect it spina bifida occulta: vertebral arch fails to fuse but nothing herniate out of it; has normal a-fetoprotein meningocele: meninges (dura mater, arachnoid mater) herniate through defect myelomeningocele: meninges and neural tissue herniate through the bony defect

a dislocation of the ________ bone may lead to median nerve impingement and _____________.

a dislocation of the lunate bone may lead to median nerve impingement and carpal tunnel syndrome.

Gout

a hereditary metabolic disease that is a form of acute arthritis, characterized by excessive uric acid in the blood and around the joints Crystals are negatively birefringent. Caused by either an underexcretion of uric acid (idiopathic) or overproduction (like Lesch-Nyan syndrome, Von Gierke's, tumor lysis syndrome). Risk factors: male, hyperuricemia, obesity, diabetes, alcohol use, renal disease Treatment: actute = NSAIDs, colchicine; chronic = allopurinal, febuxostat

presentation: tightness in knee; posterior knee swelling, most apparent when standing; pain with knee extension or activity history: trauma, athlete, rheumatoid arthritis, gout

baker's cyst (popliteal bursitis)

Supracondylar fracture of humerus will injure which artery and nerve? What will be the motor/sensory deficits?

brachial artery and median nerve proximal median nerve injury = problems with wrist flexion; loss of opposition, abduction, and flexion of the thumb; loss of fxn on first 2 lumbricals "hand of benediction" - when trying to make a fist, the first three digits stay extended due to loss of first two lumbricals and thenar muscles.

A 68-year-old woman presents to the emergency department after a motor vehicle crash. She is having extreme back pain; she had to be brought on a stretcher because she cannot walk. She says that she cannot feel her perineal area or inner thighs. She is unable to urinate when asked for a urine sample. What is her most likely diagnosis?

cauda equina syndrome

presentation: sudden low back pain, weakness of lower extremity, pain in back of legs, numbness of the perineum, buttocks, and inner thighs; bladder/bowel incontinence, urinary retention, sexual dysfunction

cauda equina syndrome needs urgent MRI/CT and surgical decrompression

carpal tunnel syndrome (pathogenesis and treatment)

compression of the median nerve as it passes between the ligament (flexor retinaculum/transverse carpal ligament) and the carpal bones and tendons of the wrist Sensation to palm is spared b/c palmar cutaneous nerve branches off median nerve before the carpal tunnel Treatment: rest, immobilization, NSAIDs, corticosteroids, stretching/strengthening exercise, surgery

presentation: severe low back pain, "shooting" leg pain, leg numbness, difficulty walking physical exam: straight leg raise test, reverse straight leg test positive history: trauma, like heavy lifting

herniated disc

JG is a 60-year-old man with his own moving company. He has chronic low back pain and generally works in a supervisory capacity over several employees. Last week, there was a viral outbreak amongst his workers, so he had to fill in for a couple of jobs. "I think I sprained my back. Now I have shooting pain down my leg, and I can hardly walk," he says. He has no changes in urination and no perineal symptoms. On exam, he has reproducible pain into his calf when his leg is raised. He cannot overcome resistance in extending his right great toe, but his Achilles and patellar reflexes are normal. What is the most likely diagnosis?

herniated disc (I stole this from a scholar Rx brick lol)

Housemaid's knee vs Clergyman's knee

housemaid's knee = prepatellar bursitis clergyman's knee = infrapatellar bursitis treatment for both: NSAIDs,

which rotator cuff muscle is commonly injured in baseball pitchers?

infraspinatus

Paget disease of bone histology (this isn't really a question, just know what the histology looks like)

key findings: increased/prominent cement lines, mosaic pattern of woven and lamellar bone

presentation: tenderness and pain on lateral elbow physical: positive Cozen test (pain in lateral elbow with wrist extension) history: tennis player/athlete

lateral epicondylitis

A patient comes to the hospital after being stabbed between the fourth and fifth ribs, at the right mid-axillary line. When the patient is asked to press against the wall with their arms, the right scapula protrudes from the back. Which of the following nerves is most likely injured?

long thoracic nerve

A winged scapula is associated with an injury of the ______ nerve, which innervates the ____________ muscle

long thoracic nerve, serratus anterior muscle serratus anterior functions in protraction and rotation of the scapula

what is the most common cause of back pain?

muscle strain strain = tearing of muscle fibers sprain = tearing of ligaments

Osteoarthritis (pathogenesis and treatment)

non-inflammatory arthritis of weight-bearing joints (knee and hip) due to wear and tear destruction of articular cartilage --> macrophage and cytokine response - most common arthritis - progression is certain and irreversible - more common in females, obese patients - treatment: activity modification, acetaminophen, NSAIDs, glucocorticoids; severe OA = total joint replacement (arthroplasty)

presentation: pain in weight-bearing joints, usually asymmetric; worse at night, better in the morning, worse with movement, bowleg, Heberden nodes, Bouchard nodes Radiograph: asymmetric joint space narrowing, osteophytes Labs: joint fluid WBC <2000 Pertinent negatives: lack of MCP involvement, lack of systemic symptoms (fever, fatigue, weight loss)

osteoarthritis

Baker's cyst

popliteal cyst, a fluid filled sac behind the knee can be diagnosed with ultrasound or MRI Treatment: RICE, elevation, needle aspiration

in a midshaft fracture of humerus, what is the possible nerve injury, motor deficit, sensory deficit?

radial nerve injury motor deficit = wrist drop (loss of elbow, wrist, and finger extension), decreased grip strength sensory deficit: loss of sensation over posterior arm/forearm - other radial nerve injuries: Saturday night palsy