Polymyalgia Rheumatica

aching with normal strength · sedimentation rate and creatine kinase · giant cell arteritis overlap · prednisone responseIs this pain and stiffness with normal strength after 50, and does low-dose prednisone clear it within days?

1Illness script

2Urgent risks

3Differential

4Workup

5Diagnostic criteria

6Severity

7Treatment

8Follow-up

Practice

1. 72 yo F, bilateral shoulder and hip girdle aching, morning stiffness 90 min, ESR 62, strength 5/5 → Polymyalgia rheumatica → prednisone 15 mg daily
2. 72 yo F with known PMR, new jaw claudication and temporal tenderness → Giant cell arteritis → high-dose prednisone immediately, biopsy after
3. 68 yo M, progressive proximal weakness, CK 4,000, normal ESR → Polymyositis → EMG and muscle biopsy
4. 70 yo F on atorvastatin, proximal aching, CK 900 → Statin myopathy → stop the statin and recheck CK
5. 66 yo F, proximal aching, ESR 12, TSH 14 → Hypothyroid myopathy → levothyroxine
6. 74 yo F with presumed PMR, no response after a week of prednisone 15 mg → Reconsider the diagnosis – PMR responds within days
7. 63 yo F, widespread pain, non-restorative sleep, normal ESR and CK → Fibromyalgia

Wrist and Hand Pain and Numbness

snuffbox vs styloid vs thumb base · occult scaphoid fracture · carpal tunnel and its mimics · when not to imageWhere exactly is the tenderness or numbness, and would a negative test change anything?

1Presentation

2Urgent risks

3Differential

Thenar atrophy means the median nerve; hypothenar atrophy, the ulnar.

4Workup

Practice

1. 22-year-old man fell on his outstretched hand playing basketball tender in the anatomic snuffbox wrist radiographs with a scaphoid view are negative Pain on gripping; no deformity Afebrile · radial pulse normal · sensation intact → Thumb spica cast and re-image in about 2 weeks → snuffbox tenderness after a fall is a scaphoid fracture until proven otherwise; first films miss up to about 30%: thumb spica cast and re-image in about 2 weeks
2. 22-year-old man, a professional goalkeeper, has snuffbox tenderness after a fall radiographs negative needs a definitive answer before a match next week Thumb spica cast in place Afebrile · sensation intact → MRI of the wrist → MRI shows an occult fracture immediately when a 2-week wait for repeat films is not acceptable
3. 22-year-old man has 6 months of wrist pain fell on an outstretched hand last winter, not imaged then tender in the anatomic snuffbox Grip weak and painful Afebrile · radiograph: sclerotic proximal scaphoid with a fracture gap → Avascular necrosis and nonunion → the blood supply runs retrograde to the proximal pole, so a missed fracture ends in avascular necrosis and nonunion
4. 68-year-old woman fell on her outstretched hand on ice tender over the distal radius, not the snuffbox wrist looks like a dinner fork Radiograph: distal radius fracture with dorsal angulation Afebrile · radial pulse normal → Colles fracture → dorsal angulation of a distal radius fracture after a fall is a Colles fracture; snuffbox tenderness would point to the scaphoid
5. 24-year-old woman was diagnosed with a scaphoid fracture on MRI fracture line near the end closest to the forearm nondisplaced She asks about the risk of the bone dying Afebrile · sensation intact → Proximal pole → the proximal pole carries the highest avascular necrosis risk: its blood supply arrives last, retrograde from the distal end
6. 22-year-old man fell from his skateboard onto his outstretched hand tender in the anatomic snuffbox radiograph: displaced fracture through the scaphoid waist No other injury; pain on gripping Afebrile · radial pulse normal → Surgical fixation → a displaced waist or proximal pole fracture goes to surgical fixation; casting is for the presumed fracture with a negative film
7. 29-year-old woman at 34 weeks of gestation has numb hands tingling of the thumb, index and middle fingers shakes her hands to relieve it Thenar sensation spared; no neck pain BP 118/72 mm Hg · mild hand and ankle edema → CTS of pregnancy → numbness of the thumb, index and middle fingers relieved by shaking, with thenar sparing and no neck pain at 34 weeks, is carpal tunnel syndrome of pregnancy: nocturnal splint; it usually resolves after delivery
8. 48-year-old man has new numbness in both hands at night his rings no longer fit coarse facial features and large hands Shoe size has increased BP 148/92 mm Hg · glucose 168 mg/dL → Acromegaly → bilateral carpal tunnel syndrome with enlarging hands and coarse features is acromegaly: IGF-1 (insulin-like growth factor 1)
9. 52-year-old woman has numbness in both hands at night fatigue and 6 kg of weight gain cold intolerance, dry skin Delayed relaxation of ankle reflexes HR 56/min · BP 128/84 mm Hg → Hypothyroidism → bilateral carpal tunnel syndrome with fatigue and weight gain is hypothyroidism: TSH (thyroid-stimulating hormone)
10. 60-year-old man on long-term hemodialysis for 12 years has numb hands at night both hands, thumb to middle finger, for months shoulder pain and stiffness No diabetes Afebrile · BP 138/80 mm Hg → β2-microglobulin amyloidosis → long-term hemodialysis with carpal tunnel syndrome is beta-2 microglobulin amyloidosis
11. 58-year-old woman has 2 years of numbness of the thumb, index and middle fingers thenar atrophy weak thumb abduction Nerve conduction: severe median slowing at the wrist Afebrile · TSH normal → Carpal tunnel release → thenar atrophy means the nerve is losing motor fibers: skip conservative therapy and release the carpal tunnel
12. 32-year-old woman, a new mother, has 4 weeks of radial wrist pain worse lifting her baby out of the crib tender over the radial styloid Finkelstein test positive Afebrile · no snuffbox tenderness → De Quervain tendinopathy → radial styloid tenderness with a positive Finkelstein test is de Quervain tendinopathy: a clinical diagnosis; thumb spica splint and an NSAID (nonsteroidal anti-inflammatory drug)
13. 65-year-old woman has thumb base pain when opening jars squared appearance of the thumb base grind test positive Radiograph: joint space narrowing at the base of the thumb Afebrile · Finkelstein test negative → First CMC osteoarthritis → thumb base pain with a positive grind test in an older patient is first carpometacarpal (CMC) osteoarthritis
14. 24-year-old woman, sexually active, has wrist tenosynovitis: painful swelling over both wrists migratory joint pains for 4 days a pustular rash: a few pustules on her forearms New partner last month T 38.4 °C · BP 112/70 mm Hg → Disseminated gonococcal infection → tenosynovitis, migratory arthralgia and pustules is disseminated gonococcal infection: nucleic acid amplification test (NAAT), blood cultures and ceftriaxone
15. 32-year-old woman was diagnosed with de Quervain tendinopathy and is still in pain 6 weeks of a thumb spica splint and an NSAID Finkelstein test still positive No numbness Afebrile · no swelling over the snuffbox → Corticosteroid injection → after splint and NSAID fail, the next rung is a corticosteroid injection; release of the first dorsal compartment comes after that
16. 40-year-old man, a competitive rower, has dorsal forearm pain worse with repetitive wrist extension crepitus a few centimeters proximal to the wrist with motion Radial styloid not tender Afebrile · Finkelstein test negative → Intersection syndrome → pain with crepitus about 4 cm proximal to the wrist in a rower is intersection syndrome

Low Back Pain in an Adult

red flags and when to image · acute pain with no red flags · inflammatory back pain and spondyloarthritisIs there a red flag or a neurologic deficit, and does the pain improve when the patient moves?

1Presentation

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3Differential

4Workup

Practice

1. 47-year-old woman has 2 days of low back pain now pain down both legs cannot pass urine since this morning Numb over the buttocks and inner thighs Afebrile · bladder scan 800 mL · anal tone reduced → Emergent MRI + decompression → urinary retention and saddle anesthesia are cauda equina syndrome: emergent MRI and decompression
2. 40-year-old man has 1 week of low back pain began 1 day after moving furniture tender over the paraspinal muscles, not the spine No fever, chills, constipation or urinary incontinence Afebrile · reflexes, strength and sensation normal → No imaging → acute pain with a mechanical cause and a history full of pertinent negatives needs no imaging: an NSAID (nonsteroidal anti-inflammatory drug) and stay active
3. 62-year-old woman has 6 weeks of low back pain treated for breast cancer 4 years ago worse at night, not relieved by rest Neurologic exam normal Afebrile · no weight loss → MRI for metastasis → prior cancer with night pain needs MRI with contrast even with a normal neurologic exam
4. 72-year-old woman on chronic prednisone has sudden back pain began after a minor fall point tenderness over one midline lumbar vertebra No leg pain, numbness or weakness Afebrile · neurologic exam normal → Vertebral compression fracture → age over 70, chronic steroids and a minor fall point to a vertebral compression fracture: lumbar radiograph first
5. 47-year-old woman has 5 days of low back pain after gardening chronic kidney disease, stage 3 bleeding gastric ulcer last year No fever, weight loss or bladder change Creatinine 1.9 mg/dL · neurologic exam normal → Acetaminophen or a topical NSAID → same tier, a different agent: kidney disease and a prior bleed rule out an oral NSAID, so acetaminophen or a topical NSAID
6. 47-year-old woman has 3 weeks of low back and left leg pain now cannot lift the front of her left foot foot slaps on walking No bladder or bowel change Afebrile · left ankle dorsiflexion 3/5 · saddle sensation normal → Urgent MRI → a new foot drop is a progressive deficit: urgent MRI, without the bladder or saddle signs that make it an emergency
7. 55-year-old woman has 2 months of back pain that wakes her at night not relieved by getting up and moving lost 6 kg without trying Treated for breast cancer 3 years ago Afebrile · neurologic exam normal → Metastasis → night pain unrelieved by moving, with prior cancer and weight loss, is metastasis, not inflammatory back pain: MRI
8. 34-year-old man who injects drugs has 1 week of back pain fever and chills focal tenderness over one lumbar spinous process No leg weakness T 38.9 °C · erythrocyte sedimentation rate 98 mm/h → Vertebral osteomyelitis → fever with focal spinal tenderness in injection drug use is vertebral osteomyelitis: MRI with contrast plus blood cultures
9. 47-year-old woman has 8 weeks of low back pain pain shoots down the lateral leg to the top of the foot no better with an NSAID No bladder change Afebrile · strength normal · left straight-leg raise positive → MRI, PT, consider epidural → radicular symptoms past 6 weeks: MRI (magnetic resonance imaging) and physical therapy (PT), with an epidural steroid injection if conservative care keeps failing
10. 72-year-old man has 1 hour of sudden severe back pain pulsatile, tender mass above the umbilicus pale and light-headed Smoker with peripheral arterial disease and hypertension BP 82/50 mm Hg · HR 124/min → Ruptured abdominal aortic aneurysm → back pain with a pulsatile mass and hypotension is a ruptured abdominal aortic aneurysm: straight to surgery; do not delay for CT
11. 68-year-old man has 1 year of buttock and leg pain when walking relieved by sitting or leaning forward on a shopping cart cycles without pain No back pain at rest Afebrile · pedal pulses normal · strength normal → Spinal stenosis → leg pain on walking relieved by flexing forward, with normal pulses, is spinal stenosis
12. 38-year-old man has 2 weeks of low back pain pain shoots below the right knee into the foot right straight-leg raise positive Began while lifting a sofa Afebrile · strength normal → Radiculopathy → pain radiating below the knee with a positive straight-leg raise is radiculopathy
13. 34-year-old man has 4 months of low back pain better with activity, worse with rest morning stiffness over 30 minutes Wakes in the second half of the night Afebrile · neurologic exam normal → Inflammatory back pain → under 40, over 3 months, better with movement: inflammatory back pain; sacroiliac joint radiographs, with HLA-B27 supportive only
14. 26-year-old man has 6 months of low back pain improves with exercise, worse after sitting morning stiffness for an hour Sacroiliac joint radiographs are normal Afebrile · reduced Schober test · chest expansion reduced → MRI of the SI joints → radiographs normal with suspicion still high: MRI of the sacroiliac joints shows active sacroiliitis first; HLA-B27 is supportive only
15. 30-year-old man with HLA-B27-positive sacroiliitis has a red, painful left eye began yesterday photophobia and blurred vision No discharge or itching Afebrile · small left pupil · redness greatest around the cornea → Anterior uveitis → the eye complication of spondyloarthritis is anterior uveitis: topical steroid and a cycloplegic
16. 45-year-old man with a fused, bamboo-like spine for 15 years new exertional dyspnea diastolic murmur at the left sternal border No chest pain or syncope BP 150/50 mm Hg · HR 76/min → Aortic regurgitation from aortitis → aortitis widens the aortic root: aortic regurgitation
17. 52-year-old man with HLA-B27-positive sacroiliitis for 20 years new neck pain after a minor fall pain on any neck movement Old radiographs show a fused spine Afebrile · strength and sensation normal → Spinal fracture → a rigid spine is brittle: fracture after minor trauma, so CT (computed tomography) of the spine
18. 24-year-old man has 1 week of a swollen right knee and left ankle bloody diarrhea 2 weeks ago red eyes and burning on urination No rash or nail changes T 37.8 °C · rheumatoid factor negative → Reactive arthritis → asymmetric lower-limb arthritis weeks after dysentery, with conjunctivitis and urethritis, is reactive arthritis
19. 68-year-old man with diabetes has back stiffness radiograph: flowing ossification along the front of 4 or more vertebrae sacroiliac joints normal No morning stiffness over 30 minutes Afebrile · HLA-B27 negative → Diffuse idiopathic skeletal hyperostosis → flowing anterior ossification with spared sacroiliac joints in an older man with diabetes is diffuse idiopathic skeletal hyperostosis, not spondyloarthritis

Hip Injury in an Adult

fracture vs posterior dislocation by leg position · the 6-hour and 72-hour clocks · the shoulder mirror · reduction within about 6 hoursIs the leg externally rotated and abducted, or internally rotated, adducted and flexed?

1Presentation

2Urgent risks

3Differential

4Workup

The shoulder mirrors the hip: the common anterior shoulder dislocation is held turned out (axillary nerve at risk), the rare posterior one turned in.

Practice

1. 78 yo F after a fall, leg shortened and externally rotated → Femoral neck fracture → X-ray, then arthroplasty
2. 28 yo M after a head-on collision, leg shortened, internally rotated, adducted and flexed → Posterior hip dislocation → reduction within 6 hours
3. 28 yo M with foot drop after a posterior hip dislocation → Sciatic nerve injury
4. 78 yo F with a displaced femoral neck fracture → Arthroplasty → retinacular vessel disruption risks avascular necrosis (AVN)
5. 28 yo M whose hip dislocation was reduced at 10 hours → Increased risk of femoral head osteonecrosis
6. 70 yo M after a fall, leg shortened and externally rotated but abducted, groin pain → Intertrochanteric fracture

Hip and Thigh Pain and Numbness

groin vs lateral vs buttock · tendon vs nerve · which nerves have motor fibers · when to imageWhere is the pain, and is there tenderness, weakness or only numbness?

1Presentation

2Urgent risks

3Differential

4Workup

Practice

1. 54-year-old woman has 3 months of lateral hip pain she calls burning worse lying on that side and on stairs point tenderness over the bony lateral hip Hip range of motion full; neurologic exam normal Afebrile · body mass index 33 → Greater trochanteric pain syndrome → tenderness over the trochanter with a normal neurologic exam outweighs the word burning: greater trochanteric pain syndrome (GTPS); activity modification, an NSAID (nonsteroidal anti-inflammatory drug) and physical therapy
2. 58-year-old woman was diagnosed with greater trochanteric pain syndrome 2 months ago still tender over the trochanter 8 weeks of an NSAID and abductor-strengthening therapy No weakness or limp Afebrile · hip range of motion full → Corticosteroid injection → refractory to an NSAID and physical therapy: corticosteroid injection; MRI is for suspected tendon tear
3. 66-year-old woman has 6 months of lateral hip pain weak hip abduction Trendelenburg gait Tender over the greater trochanter; worse lying on that side Afebrile · no back pain · sensation and reflexes normal · hip internal rotation full → Gluteus medius tendon tear → abductor weakness with a Trendelenburg gait is the severe end of the GTPS spectrum, a gluteus medius tendon tear: MRI; weakness separates a tear from uncomplicated GTPS, which has normal strength
4. 67-year-old man has 2 years of groin pain pain radiates to the knee, worse after walking internal rotation reduced, with crepitus Morning stiffness under 30 minutes Afebrile · body mass index 29 · no trochanteric tenderness → Hip OA → groin pain with reduced internal rotation and crepitus is the joint itself, hip osteoarthritis: radiograph
5. 26-year-old woman training for a marathon has groin pain pain when she hops on that leg log-roll of the leg reproduces the groin pain Hip radiograph normal; irregular periods Afebrile · body mass index 18 → Femoral neck stress fracture → groin pain on hopping in a runner with a normal film is a femoral neck stress fracture: MRI; irregular periods and low weight suggest the female athlete triad
6. 30-year-old man, a cyclist, has lateral knee pain tender over the lateral femoral condyle Noble test reproduces it Hip examination normal; rides 200 km a week Afebrile · BP 118/70 mm Hg · no knee effusion → IT band syndrome → lateral knee pain at the femoral condyle with a positive Noble test is iliotibial (IT) band syndrome, a knee diagnosis, not a hip one
7. 40-year-old man has numbness over the upper lateral thigh a patch that burns when he wears a tight belt no tenderness over the trochanter; no back pain Strength normal; reflexes normal Afebrile · body mass index 36 → Meralgia paresthetica → a sensory-only patch on the upper lateral thigh with normal strength is meralgia paresthetica; a radiculopathy usually brings back pain, a dermatomal pattern or weakness
8. 16-year-old boy has 3 months of thigh pain pain wakes him at night ibuprofen relieves it dramatically No trauma; no weight loss Afebrile · radiograph: small lucency with sclerosis in the proximal femur → Osteoid osteoma → night pain dramatically relieved by NSAIDs in a young patient is an osteoid osteoma; CT (computed tomography) shows the nidus
9. 45-year-old man on prednisone for 2 years has progressive groin pain drinks heavily range of motion reduced in all planes Hip radiograph normal; no trauma Afebrile · BP 124/78 mm Hg · hemoglobin normal → AVN → steroids or alcohol with groin pain and a normal film is avascular necrosis (AVN) of the femoral head: MRI (magnetic resonance imaging)
10. 38-year-old woman has 2 months of right buttock pain pain runs down the back of the thigh worse sitting, tender deep in the buttock No back pain; straight-leg raise negative Afebrile · strength, reflexes and sensation normal → Piriformis syndrome → buttock pain sorts to the spine, sacroiliac joint or piriformis; worse sitting with piriformis tenderness and a normal neurologic exam fits piriformis syndrome
11. 44-year-old man, obese, has burning numbness over the upper lateral thigh wears a tight work belt every day no back pain Strength 5/5 throughout Afebrile · BP 136/86 mm Hg · reflexes normal · body mass index 37 → Meralgia paresthetica → the lateral femoral cutaneous nerve is purely sensory, so full strength confirms meralgia paresthetica: weight loss and loosening restrictive belts
12. 44-year-old man has numbness over the anterior thigh and medial leg weak knee extension reduced patellar reflex Began after a long procedure in the lithotomy position; no back pain Afebrile · BP 128/80 mm Hg → Femoral neuropathy → anterior thigh and medial leg numbness with quadriceps weakness and a reduced patellar reflex is a femoral neuropathy
13. 44-year-old man has 2 months of lateral thigh numbness back pain radiating to the knee reduced patellar reflex, weak hip flexion Femoral stretch test positive; no bladder symptoms Afebrile · BP 132/84 mm Hg → L2–L3 radiculopathy → back pain with weakness, a reduced reflex and a positive femoral stretch test is an L2 to L3 radiculopathy; meralgia has no motor or reflex loss
14. 56-year-old woman has 2 months of lateral hip pain point tenderness over the bony lateral hip no numbness Worse lying on that side and climbing stairs Afebrile · strength normal · knee examination normal → Trochanteric bursitis → trochanteric tenderness without numbness is trochanteric bursitis, the older, misnamed label for greater trochanteric pain syndrome; the exam may still use it
15. 60-year-old man with diabetes has severe right thigh pain proximal leg weakness and thigh wasting lost 7 kg in 2 months Asymmetric; the left leg is spared Afebrile · hemoglobin A1c 9.1% → Diabetic amyotrophy → severe asymmetric thigh pain, proximal weakness and weight loss in diabetes is diabetic amyotrophy; polyneuropathy is symmetric and starts in the feet
16. 44-year-old man has burning numbness over the upper lateral thigh since he started wearing a tool belt strength and reflexes normal No back pain Afebrile · sensory loss in a patch on the upper lateral thigh → No testing; it is a clinical diagnosis → meralgia paresthetica is a clinical diagnosis; no imaging or electrodiagnostic testing is needed

Osteoarthritis

pharmacotherapy ladder · class right, member wrong · ketorolac's 5-day maximum · excluding inflammatory arthritisIs the offered drug the right member of the right class for a chronic condition in this patient?

1Illness script

2Urgent risks

3Differential

Spine osteoarthritis is the usual cause of spinal stenosis; hip osteoarthritis can mimic trochanteric pain.

4Workup

5Diagnostic criteria

6Severity

7Treatment

8Follow-up

Practice

1. 68 yo F with knee osteoarthritis still limited by pain despite exercise and weight loss → Topical diclofenac → the first-line drug for knee OA
2. Knee OA with chronic kidney disease or prior GI bleed → Topical NSAID or acetaminophen, avoid systemic NSAIDs
3. Refractory pain despite NSAIDs and physical therapy → Intra-articular glucocorticoid
4. Morning stiffness >1 hour with symmetric metacarpophalangeal/proximal interphalangeal synovitis → Rheumatoid arthritis → rheumatoid factor/anti-CCP, DMARDs
5. Acute monoarticular knee with warmth and effusion → Arthrocentesis before any pharmacotherapy
6. End-stage disease, failed all conservative measures → Joint replacement

Hot Joint or Bursa in an Adult

septic arthritis, crystal arthritis and septic bursitis · synovial fluid thresholds · prosthetic joint and gonococcal branches · post-injection flareIs joint motion preserved, and has the fluid been sampled before any treatment?

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Practice

1. 54-year-old woman has 1 day of a hot, swollen, red right knee severe pain on passive range of motion obesity, hypertension and diabetes Radiograph: joint space narrowing T 38.5 °C · HR 102/min · no rash → Arthrocentesis → nothing on exam excludes infection, and diabetes and joint space narrowing are risk factors for it: aspirate before any treatment
2. 47-year-old woman has 2 days of a hot, swollen left knee pain with any passive motion aspirate: 68,000 white cells/mm³, 85% neutrophils No crystals seen under polarized light T 38.6 °C · Gram stain pending → Septic arthritis → over 50,000 white cells with over 75% neutrophils and no crystals is septic arthritis: vancomycin after cultures, then drainage
3. 55-year-old man woke with severe pain at the base of the big toe red, swollen first metatarsophalangeal joint began after a steak dinner Aspirate: 12,000 white cells/mm³ T 37.6 °C · negatively birefringent needles → Gout → an inflammatory count with negatively birefringent needles is gout: an NSAID (nonsteroidal anti-inflammatory drug) or colchicine
4. 47-year-old woman has 2 days of a hot, swollen right knee aspirate shows negatively birefringent needle crystals and 60,000 white cells/mm³ Gram stain shows no organisms T 38.2 °C · culture pending → Treat as septic → crystals do not exclude coexisting infection: over 50,000 white cells is treated as septic until culture says otherwise
5. 72-year-old woman has 1 day of a hot, swollen right knee radiograph shows chondrocalcinosis aspirate: positively birefringent rhomboid crystals Gram stain shows no organisms T 37.8 °C · aspirate 18,000 white cells/mm³ → Pseudogout → positively birefringent rhomboids with chondrocalcinosis are calcium pyrophosphate crystals: pseudogout
6. 68-year-old man has 3 weeks of right knee pain had a knee replacement 2 years ago aspirate: 3,200 white cells/mm³, 82% neutrophils No crystals seen T 37.4 °C · radiograph: no loosening seen → Prosthetic joint infection → around a prosthesis the 50,000 threshold does not apply: over 3,000 white cells with over 80% neutrophils is prosthetic joint infection
7. 24-year-old woman has 4 days of joint pain moving from knee to wrist tenosynovitis over the wrist extensors a few pustules on the hands Sexually active, inconsistent condom use T 38.1 °C · no back pain or conjunctivitis → Disseminated gonococcal infection → migratory polyarthralgia, tenosynovitis and pustules are disseminated gonococcal infection: NAAT and cultures of cervix, urethra, pharynx and rectum
8. 47-year-old woman has a hot, swollen left knee and fever red, warm cellulitis over the front of the knee the joint must be sampled Diabetes, on metformin T 38.4 °C · pain with passive motion · knee effusion → Arthrocentesis straight through the cellulitis → a needle through cellulitis seeds the joint: aspirate through clean skin or under image guidance
9. 60-year-old man with sickle cell disease has a hot, swollen left knee pain with any passive motion aspirate cloudy, cultures drawn Empiric antibiotics are being chosen T 38.7 °C · aspirate 90,000 white cells/mm³ → Add Salmonella to coverage → sickle cell disease adds Salmonella to the organisms to cover
10. 70-year-old man has 2 days of a diffusely swollen right knee severe pain with any passive motion fever and chills No swelling localized over the kneecap T 38.8 °C · large knee effusion → Septic arthritis → pain with any passive motion and a diffuse effusion is the joint, not the bursa: aspirate the joint
11. 52-year-old man has a red, hot, tender swelling over the kneecap fever since yesterday full, painless passive knee motion Kneels on concrete at work T 38.6 °C · no knee effusion → Septic prepatellar bursitis → preserved joint motion with swelling over the bursa is extraarticular: septic prepatellar bursitis, aspirate the bursa
12. 45-year-old man, a floor installer, has 3 days of knee swelling boggy swelling over the kneecap, red and warm knee range of motion intact Serum uric acid not yet drawn T 37.4 °C · no knee effusion → Aspirate the bursal fluid → redness and warmth make infection plausible: aspirate the bursal fluid before presuming crystals or overuse
13. 49-year-old man was diagnosed with septic prepatellar bursitis no improvement after 3 days of antibiotics swelling and redness unchanged Culture grew Staphylococcus aureus T 38.0 °C · knee motion still full → Incision and drainage of the bursa → failure to improve on antibiotics is the drainage gate: incision and drainage of the bursa
14. 58-year-old woman has worsening right shoulder pain began 4 days after a subacromial corticosteroid injection fever and myalgias Pain was mild the day after the injection T 38.4 °C · white cells 14,000/mm³ → Image-guided aspiration of the bursa → pain worsening days after an injection is iatrogenic inoculation of skin flora: image-guided aspiration of the deep bursa
15. 60-year-old man has severe right shoulder pain began 6 hours after a corticosteroid injection already easing by the next morning No chills or redness at the injection site Afebrile · white cells normal · no swelling → Post-injection steroid flare → pain within hours that settles within 48 hours is a post-injection steroid flare; infection worsens over days

Septic Arthritis and Transient Synovitis in a Child

Kocher criteria count · ultrasound for an effusion · aspirate at 3 or 4, or at 2 with an effusion and raised blood tests · transient synovitis vs Perthes by the courseHow many Kocher criteria are present: aspirate now, or treat with NSAIDs and recheck?

1Illness script

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3Differential

4Workup

5Diagnostic criteria

6Severity

7Treatment

8Follow-up

Practice

1. 3-year-old boy with 1 day of right hip pain refuses to bear weight on the right leg cries with any passive movement of the hip No trauma; no recent illness T 39.1 °C · WBC 15,000/mm³ · ESR 62 mm/h → Arthrocentesis → 4 of 4 Kocher criteria; draw a blood culture and aspirate before antibiotics
2. 7-year-old boy with 2 days of left hip pain will not walk; lies with the hip flexed, abducted and externally rotated screams with gentle passive rotation No point tenderness over the femur T 39.0 °C · WBC 14,000/mm³ · ESR 90 mm/h → Septic arthritis of the hip → Kocher 4 of 4; the position only shows an effusion (it occurs in transient synovitis too); motion this painful is the joint, not the bone
3. 4-year-old boy limping since a cold 10 days ago today he refuses to bear weight on the left leg holds the left hip flexed and turned outward T 39.2 °C · ESR 78 mm/h · WBC pending → Arthrocentesis before antibiotics → fever, refusal to bear weight and an ESR over 40 are 3 of 4 with the WBC still pending; a recent cold does not make it benign
4. 6-year-old girl with 4 days of a limp after a cold 10 days ago walks, favoring the right leg; well appearing T 37.9 °C · WBC 11,500/mm³ · ESR 18 mm/h · CRP 0.8 mg/dL (normal under 1) · ultrasound: effusions in both hips → Transient synovitis → Kocher 0 of 4; an effusion occurs in both diseases, but effusions in both hips favor transient synovitis (septic arthritis is usually one-sided): NSAIDs and a recheck
5. 6-year-old girl with 4 days of right knee soreness and a limp began after gymnastics practice right knee: full, painless motion, no swelling or tenderness right hip: internal rotation limited and painful Afebrile · bears weight → Ultrasound of both hips → a normal knee exam sends you to the hip, which refers pain to the knee; ultrasound of both hips looks for effusions
6. 6-year-old girl with 3 days of a left-sided limp well appearing; walks and bears weight mild pain at the end of hip rotation T 37.4 °C · WBC 8,900/mm³ · ESR 12 mm/h · CRP normal · ultrasound: small effusions in both hips → Arthrocentesis of both hips → Kocher 0 of 4: the needle is for 3 or 4, or 2 with an effusion and raised blood tests; treat and recheck
7. 4-year-old boy with 2 days of fever and refusal to walk ultrasound-guided hip aspiration: cloudy fluid 80,000 WBC/mm³, 90% neutrophils; Gram stain pending Blood culture drawn before the tap T 39.4 °C · BP 98/60 mm Hg → Surgical drainage plus IV antibiotics → fluid over 50,000 WBC/mm³, neutrophil-predominant: a septic hip is a surgical emergency, and antibiotics alone cannot decompress the joint
8. 2-year-old boy with sickle cell disease 1 day of fever and refusal to bear weight on the left leg screams when the left hip is moved Ultrasound shows a left hip effusion; aspiration is planned T 39.4 °C · WBC 18,000/mm³ → Haemophilus influenzae → sickle cell disease (functional asplenia) adds encapsulated organisms such as H influenzae in the joint; Salmonella is its bone (osteomyelitis) organism; Kingella also fits his age, and gonococcus is the adolescent's
9. 3-year-old boy with 2 days of fever and refusal to walk hip aspirate: purulent, 95,000 WBC/mm³, mostly neutrophils the operating room is not free until tomorrow Started on IV antibiotics after cultures T 39.2 °C · ESR 70 mm/h → Femoral head osteonecrosis → pus under pressure inside the capsule cuts off blood to the femoral head; delay also risks growth arrest
10. 4-year-old boy with 4 days of a limp and left thigh pain point tenderness over the distal femoral metaphysis passive hip and knee motion nearly full and only mildly painful Well appearing T 38.6 °C · CRP 6 mg/dL · radiographs normal → Osteomyelitis → fever with point bone tenderness and preserved motion is bone, not joint: MRI; radiographs are normal early
11. 5-year-old boy treated with ibuprofen for a post-viral limp 4 weeks later he still limps, worse after play hip abduction and internal rotation now limited No fever, night pain or weight loss T 37.0 °C · WBC and ESR normal → Radiographs of both hips → most transient synovitis resolves within 2 weeks; a limp past that needs hip radiographs for Legg-Calvé-Perthes disease
12. 11-year-old girl with polyarticular juvenile idiopathic arthritis on methotrexate wrists, knees and ankles improving 4 days of right shoulder pain, now waking her at night will not move the shoulder T 38.5 °C · synovial fluid 55,000 WBC/mm³, 80% neutrophils → Begin antibiotic therapy → one joint out of step with the rest, with fever and septic fluid on an immunosuppressant: infection, not a flare: antibiotics, then drain the joint; steroid into the joint or more methotrexate would feed it
13. 4-year-old boy with 1 day of hip pain and a limp cold 10 days ago; no trauma appears well; no bony tenderness hip motion limited by pain Vital signs normal · ultrasound: small right hip effusion · CBC and ESR pending → Ibuprofen and a recheck → afebrile and walking, and he looks well, so treat and recheck; read the labs when they return (an effusion with raised blood tests then means aspiration); the ultrasound already answered the imaging question, and his pain needs treatment

The Limping Child

sick or well first · age at onset · time course · the hip exam · imaging by the findings · treatment by cause

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Practice

1. 13-month-old girl, walking for 1 month, with a painless limp born breech asymmetric thigh skin folds left leg shorter; left hip abduction limited Her mother wore a hip harness as an infant Afebrile · no bruising or tenderness → Developmental dysplasia of the hip → breech, female, a family history, a short leg and limited abduction in a new walker: missed DDH; past 4 months, image with a radiograph
2. 2-year-old girl with a painless limp since she began walking right leg shorter than the left right hip abduction limited Born at term; no trauma; growth normal Afebrile · knees and ankles normal → Radiograph of the pelvis → missed DDH in a walker: the femoral head has ossified, so a radiograph; ultrasound is for infants under 4 months
3. 2-year-old boy who will not put weight on his right leg began yesterday after a fall at daycare that no one saw tender over the distal right tibia Well appearing Afebrile · CRP normal · hip and knee motion full → Toddler's fracture → a new limp after a minor, unwitnessed fall with tibial tenderness: tibia radiographs for a spiral fracture; corner or bucket-handle fractures suggest abuse
4. 6-year-old boy with a limp for 2 months, worse after play intermittent groin and knee pain hip abduction and internal rotation limited No fever, trauma or night pain Afebrile · CBC and ESR normal · radiograph: flattened, fragmented femoral head → Legg-Calvé-Perthes → an insidious limp over weeks with normal labs at about 5 to 10 years; early films can be normal, so MRI when they are
5. 13-year-old boy with 3 weeks of left thigh and knee pain and a limp 95th percentile for height, 50th for weight left hip internal rotation lost; the hip rotates outward when flexed Knee examination normal Afebrile · white cell count normal → Slipped capital femoral epiphysis → lost internal rotation with obligate external rotation at the growth spurt, whatever the build: AP and frog-leg radiographs of both hips
6. 10-year-old boy with 8 weeks of a swollen right knee and a limp stiff each morning, easing by midday no diarrhea, urethritis or rash beforehand Lives in a city; no tick bites T 37.2 °C · ESR 28 mm/h → Juvenile idiopathic arthritis → arthritis for 6 weeks or more with morning stiffness and no other cause; a slit-lamp eye exam screens for uveitis
7. 8-year-old boy with 5 days of painful joints and a limp left knee, then right ankle, then left elbow, one after another sore throat 3 weeks ago, untreated New soft apical murmur T 38.4 °C · ESR 60 mm/h → Acute rheumatic fever → migratory large-joint arthritis 2 to 4 weeks after pharyngitis: check an ASO titer and apply the Jones criteria; the murmur is carditis
8. 5-year-old boy with 3 weeks of a limp leg pain that wakes him at night tired; bruises easily pale; lost weight this month T 37.8 °C · hip and knee motion full → CBC with smear → a limp with night pain, bruising, fatigue or weight loss: CBC with smear for leukemia before calling anything benign
9. 14-year-old boy with 3 months of anterior knee pain worse with running and jumping in basketball tender, prominent tibial tubercle hip motion full and painless Afebrile · no night pain or weight loss → Osgood-Schlatter disease → the hip is cleared and the tibial tubercle is tender in an active adolescent: activity modification and nonsteroidal anti-inflammatory drugs (NSAIDs)

Juvenile Idiopathic Arthritis

six weeks of arthritis, then joints and fever set the subtype · mimics · macrophage activation syndrome and leukemia · uveitis screening · the treatment ladder

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5Diagnostic criteria

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Practice

1. 5-year-old girl with 6 weeks of swollen knees and wrists 3 weeks of fever to 39.5 °C each evening, normal by morning salmon-pink rash with each spike that fades hepatosplenomegaly WBC 21,000/mm³ · platelets 610,000/mm³ · ANA low-titer positive · RF negative → Systemic juvenile idiopathic arthritis → quotidian fever with an evanescent rash and 6 weeks of arthritis, with high counts: systemic JIA; a low-titer ANA does not exclude it, lupus lowers counts, and rheumatic fever's joints migrate, with carditis or erythema marginatum
2. 5-year-old girl with 2 weeks of daily fever and 3 weeks of a swollen right knee parents' log: spikes to 39.8 °C each evening rash with each spike Seen in the afternoon, well appearing T 37.0 °C · ESR 64 mm/h → Continue the evaluation for systemic JIA → quotidian fever returns to normal between spikes, so a normal clinic temperature does not exclude it; no focus and well between spikes makes a bacterial infection less likely
3. 6-year-old boy diagnosed with systemic JIA a year ago, now persistently febrile oozing at venipuncture sites hepatosplenomegaly WBC 6,000/mm³ · platelets 92,000/mm³ · ferritin 18,000 ng/mL · fibrinogen 110 mg/dL · ESR 6 mm/h (70 last month) · AST 220 U/L · triglycerides 380 mg/dL → Macrophage activation syndrome → in systemic JIA, persistent fever with ESR and fibrinogen falling as ferritin, triglycerides and AST climb, and oozing from consumed clotting factors: macrophage activation syndrome; with only the platelets low (not two cell lines), treat with high-dose steroids
4. 4-year-old girl diagnosed 1 month ago with arthritis of the left knee and right ankle ANA positive no eye pain, redness or blurred vision Knee swelling improving on naproxen Afebrile · visual acuity 20/30 both eyes → Slit-lamp exam for asymptomatic uveitis → young, ANA positive and few joints carries the highest uveitis risk, and it is silent: slit-lamp exams every 3 months
5. 4-year-old boy with 6 weeks of evening fever spikes since a trip to Costa Rica pink rash with each spike, gone by morning right knee swollen 6 weeks; spleen tip palpable Well between spikes hemoglobin 10.4 g/dL · platelets 640,000/mm³ → Systemic juvenile idiopathic arthritis → weeks of quotidian fever with an evanescent rash, mild anemia and high platelets: systemic JIA; dengue lasts days and lowers the white cells and platelets, and malaria brings periodic fever with hemolytic anemia, seen on a blood smear
6. 7-year-old boy with 4 weeks of daily evening fevers to 39.6 °C normal temperature each morning salmon rash during fevers; both knees and the left wrist swollen for 7 weeks pericardial rub Afebrile in clinic → High WBC and platelets, high ferritin; ANA and RF negative → systemic JIA is inflammation without autoantibodies: high WBC, platelets, ESR and ferritin; ANA and RF usually negative
7. 3-year-old girl with 8 weeks of a swollen, warm left knee limps after waking, better by afternoon right ankle also swollen No fever or rash; lives in a nonendemic area; no tick bites Afebrile · ANA positive → Oligoarticular juvenile idiopathic arthritis → 4 or fewer joints for 8 weeks with morning stiffness: oligoarticular JIA; nonendemic with no tick bite argues against Lyme; ANA positive and young: slit-lamp exams
8. 13-year-old girl with 2 months of aching legs, hips and back pain the same all day; no morning stiffness no joint swelling; tibias tender to pressure Strict vegan diet without fortified foods Afebrile · height and weight steady → Vitamin D deficiency → diffuse bone pain that never eases and no swollen joints, on an unfortified vegan diet: vitamin D and calcium
9. 14-year-old girl, ankles aching 3 months since starting daily walks this month knees, elbows, wrists; all swollen bilaterally stiff mornings that ease Tired despite 9 hours' sleep; new plant-based diet Afebrile · weight 95th to 90th percentile · height steady · chest normal → Naproxen → 5 or more joints within months, symmetric, stiff in the morning and easing: polyarticular JIA; naproxen first, methotrexate if it persists; deficiency pain never eases or swells joints, and falling weight with steady height is not hypothyroidism
10. 4-year-old girl labeled systemic JIA 6 weeks ago, joints improving on naproxen now pale, with petechiae on her trunk and legs lymph nodes enlarged in the neck and groin T 39.4 °C · hemoglobin 8.1 g/dL · WBC 2,100/mm³ · platelets 38,000/mm³ → Bone marrow aspiration → low counts in two or more cell lines in a child labeled systemic JIA: bone marrow first; leukemia mimics JIA with bone pain, nodes and hepatosplenomegaly
11. 9-year-old boy with 3 weeks of a swollen right knee stiff after waking, better by noon no preceding diarrhea, urethritis or rash; nonendemic area No injury; walks with a slight limp Afebrile · WBC normal · ESR 32 mm/h → Naproxen and reassess at 6 weeks → JIA needs 6 weeks of arthritis with no other cause: treat the pain and reassess before labeling it or starting methotrexate

Arm Injury in a Young Child

pull or fall · reduce or radiograph · after reduction · supracondylar nerves and artery · suspecting abuse · treatment by cause

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Practice

1. 3-year-old girl who will not use her left arm pulled up by the wrist as she stumbled holds the arm at her side, elbow slightly flexed, forearm pronated No swelling, bruising or deformity; no bony point tenderness Afebrile → Radial head subluxation → a pull on the arm under age 5, forearm held pronated, with no swelling, deformity or point tenderness: a clinical diagnosis; reduce without imaging
2. 3-year-old girl not using her right arm after being swung by her hands no swelling, deformity or point tenderness her elbow was supinated and flexed 15 minutes later she reaches for toys with that arm Afebrile → No further intervention → the maneuver was the treatment, and using the arm confirms the reduction: no radiograph or sling; counsel against pulling the arm
3. 6-year-old boy who fell off monkey bars onto his outstretched hand elbow swollen and tender above the joint will not bend or straighten it Fingers warm; radial pulse present Afebrile · lateral radiograph: posterior fat pad sign → Supracondylar fracture → a fall on an outstretched hand with elbow swelling and a posterior fat pad: supracondylar fracture; check the median nerve and the brachial artery
4. 6-year-old boy with a displaced supracondylar fracture of the right humerus right hand cool and pale no palpable radial pulse Opposes the thumb and makes a full fist; forearm compartments soft T 37.0 °C · capillary refill 5 seconds → Brachial artery injury → a pale, cool, pulseless hand after a supracondylar fracture is brachial artery injury: urgent orthopedics; thumb opposition and a full fist show the median nerve works, and soft compartments argue against compartment syndrome
5. 3-year-old girl with her second pulled elbow this year, reduced today both times her brother lifted her by one hand using the arm normally within minutes Growth and development normal; no bruises or other injuries Afebrile → Counsel the family to avoid pulling the arm → recurrence is common (27 to 46%); a fitting mechanism in a well child with no fracture needs counseling (lift under the arms), not an abuse workup
6. 10-month-old boy who will not move his left arm mother says he rolled off the sofa yesterday not yet crawling; no prior fractures Bruise on the left upper arm; white sclerae Afebrile · radiograph: spiral fracture of the humeral shaft → Non-accidental trauma → a spiral fracture in a child who cannot generate the twist, a delay in care and a history that does not fit: suspected abuse; skeletal survey (under 2 years) and report; white sclerae make osteogenesis imperfecta less likely
7. 2-year-old girl not using her arm after her mother pulled her from a puddle elbow held slightly flexed, forearm pronated; no swelling two reduction attempts, no click Still not reaching 30 minutes later Afebrile · no bony point tenderness → Radiographs of the elbow → nearly all children use the arm within about 30 minutes; still unused after two attempts: elbow radiographs for an occult fracture, and if normal, splint with close follow-up

Slipped Capital Femoral Epiphysis

lost internal rotation · films of both hips · stable vs unstable · atypical: look for an endocrine or renal cause · keep off it and pin in situDoes a child of 10 to 16 with a limp and hip-to-knee pain have films of both hips, and can the child walk even with crutches?

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Stability and slip grade: step 6. Treatment: step 7. Why the hip exam first

5Diagnostic criteria

Both hips

6Severity

Slip grade

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Practice

1. 14-year-old boy with 4 weeks of intermittent left groin pain tripped on a stair this morning; now cannot bear weight at all, even with crutches left leg lies externally rotated Afebrile · radiograph: left femoral epiphysis displaced posteriorly → Unstable slipped capital femoral epiphysis → unable to bear weight even with crutches defines an unstable slip: osteonecrosis risk up to about half; keep him off it and pin urgently, without reduction
2. 9-year-old girl was diagnosed today with a left slipped capital femoral epiphysis below the 5th percentile for height and the 10th for weight growth slowed over the past 2 years Fatigue and constipation HR 62/min · BP 100/64 mm Hg → Screen for hypothyroidism, a growth hormone disorder, panhypopituitarism and renal osteodystrophy → short and underweight is atypical at any age: look for an endocrine or renal cause alongside fixation
3. 12-year-old boy was diagnosed with a left slipped capital femoral epiphysis today pinning is scheduled right hip: no pain, full internal rotation Body mass index above the 95th percentile Afebrile · radiographs were taken of the left hip only → Radiographs of the right hip now → both hips are imaged at diagnosis: about one-fifth of patients have bilateral slips (18 to 50% across series)
4. 13-year-old boy with 3 weeks of aching right knee pain and a limp knee: no effusion, no tenderness, full painless motion ligament tests normal Plays football; no specific injury Afebrile · knee radiographs normal → Examine the hip → a normal knee exam sends you to the hip: a slip refers pain to the knee through the obturator nerve
5. 14-year-old girl 5 months after screw fixation of a slipped left capital femoral epiphysis new left groin pain and stiffness hip motion now limited in all directions Afebrile · radiograph: narrowed joint space; femoral head round, without sclerosis; screw position unchanged → Chondrolysis → a narrowed joint space means lost cartilage, and a stiff, painful hip with that film after fixation is chondrolysis, most often from a pin that entered the joint unseen; osteonecrosis shows first as sclerosis and lucency, then collapse of the head; an unchanged screw argues against hardware failure
6. 16-year-old girl, a cross-country runner, with 3 weeks of right groin pain worse with each run; now hurts to hop on the right leg recently doubled her weekly mileage Afebrile · radiographs of both hips normal → Femoral neck stress fracture → groin pain on hopping with normal films after a training increase: MRI (magnetic resonance imaging) for a femoral neck stress fracture
7. 12-year-old girl with 3 weeks of right thigh pain since a minor fall today she cannot bear weight on the right leg right leg held externally rotated Afebrile · radiograph: right femoral epiphysis displaced off the neck → Forceful closed reduction of the slip → forcing the epiphysis back raises the risk of osteonecrosis: keep her off the leg and pin it where it lies

Muscle Contusion and Myositis Ossificans

post-traumatic muscle mass · peripheral ossification · motion and function

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Practice

1. 17-year-old boy, football thigh contusion 4 weeks ago pain gone by 2 weeks, back last week indurated, mobile 3-cm anterior mass; no erythema passive knee flexion hurts; strength, sensation normal Vital signs normal · thigh girth +2 cm · pulses, calves normal → Myositis ossificans → injury, recovery, then pain with a mobile intramuscular mass weeks later, hurt by stretching the muscle: heterotopic bone; the localized post-traumatic course favors myositis ossificans; rapidly progressive pain or systemic illness needs urgent infection assessment, and an enlarging or uncertain mass needs tumor evaluation
2. 16-year-old boy was diagnosed with myositis ossificans of the quadriceps today kicked in the thigh 4 weeks ago firm mass; knee flexion limited to 90 degrees Pain limits running Afebrile · radiograph: peripheral calcification → Range-of-motion exercise with a nonsteroidal anti-inflammatory drug → range of motion and an NSAID for symptoms; consider surgical assessment for a mature lesion with persistent symptoms
3. 15-year-old girl with a firm thigh mass 3 weeks after a soccer collision mass unchanged in size over 1 week pain on passive knee flexion No night pain, weight loss or fever Vital signs normal · radiograph of the thigh normal → Repeat radiographs at follow-up → an early film may not show ossification; reassess and repeat radiographs for a typical stable lesion, while an enlarging or uncertain mass needs MRI and specialist review before biopsy
4. 16-year-old boy with 1 day of severe thigh pain after a minor scrape spreading erythema and swelling pain out of proportion to the examination Confused and ill appearing T 39.0 °C · HR 128/min · BP 92/54 mm Hg → Emergency surgical exploration with broad-spectrum antibiotics → fever, spreading erythema and pain out of proportion within a day: necrotizing infection; operate now with broad antibiotics
5. 45-year-old man who stumbled on stairs, landing on a flexed knee cannot extend the knee against gravity palpable gap just above the patella No induration or mass Sensation normal · knee radiograph: low-lying patella → Orthopedic referral for surgical repair → lost knee extension with a gap above the patella is a complete quadriceps tendon tear: surgical repair; the loss of active extension with a tendon gap distinguishes this tear from a post-traumatic intramuscular mass
6. 24-year-old man 8 weeks after a traumatic brain injury stiff, painful right hip hard mass near the joint No fall or new injury since admission Afebrile · white cell count normal · alkaline phosphatase elevated → Neurogenic heterotopic ossification → Heterotopic ossification is a recognized complication after moderate or severe traumatic brain injury.
7. 18-year-old man with quadriceps myositis ossificans diagnosed 12 months ago still painful; knee flexion limited despite range-of-motion therapy and NSAIDs Mass unchanged for 6 months Afebrile · radiograph: mature, well-defined bone → Surgical excision → a mature lesion that stays symptomatic is excised; surgical assessment is considered for a mature lesion with persistent symptoms
8. 15-year-old boy was diagnosed with quadriceps myositis ossificans this week thigh contusion 3 weeks ago firm, tender anterior mass Asks how to speed recovery before the season Afebrile · knee flexion to 100 degrees → Aggressive passive stretching and deep massage of the lesion → Vigorous stretching may aggravate the condition. Avoid massaging the injured area; use gentle motion and symptom relief.

Leg Pain in a Child

growing pains · myositis after influenza · reflexes and Guillain-Barré syndrome · leukemia and bone tumor warning signs · when to radiograph · treatment by cause

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Practice

1. 6-year-old boy, 3 months of pain in both thighs and shins only at night; worse after running days pain-free days; not worsening massage and ibuprofen help Walks, runs and plays normally Afebrile · no weight loss · hip and knee exam normal → Observation and reassurance → both legs, episodic night pain with pain-free days, a normal exam and no systemic signs: growing pains, a clinical diagnosis with no film or blood count
2. 8-year-old boy with 2 months of right thigh pain at night wakes him; ibuprofen relieves it dramatically the left leg never hurts No mass or limp Afebrile · exam otherwise normal → Order plain radiographs → night pain on one side needs a film even when ibuprofen relieves it: osteoid osteoma also hurts at night and answers to NSAIDs
3. 7-year-old girl with 3 weeks of leg pain that wakes her at night intermittent fevers pale, with scattered bruises Tender to palpation over both tibias T 38.1 °C · hip and knee motion full → Order a complete blood count with peripheral smear → bone tenderness with pallor, bruising and fever is not growing pains, which needs a normal exam: CBC with smear for leukemia
4. 7-year-old boy was diagnosed with growing pains 2 weeks ago night leg pain after soccer days exam and gait normal Parents ask about stopping soccer or buying knee braces Afebrile · no weight loss → Continue normal activity without restriction → growing pains do not limit activity (pain that does is not growing pains); keep usual activity, no braces ⚠︎; reassure, and offer massage, heat, analgesics or stretching
5. 9-year-old girl was diagnosed with growing pains 1 year ago still has night pain in both shins a few nights a month, with pain-free weeks Growing normally; plays sports Afebrile · joints and gait normal → Continued reassurance and supportive care → growing pains wax and wane for months to years and resolve by adolescence; recurrence with a normal exam is expected, not a reason to escalate
6. 10-year-old boy with night leg pain his parents read that night pain means a tumor both shins hurt, worse after sports pain-free days; ibuprofen helps Exam and gait normal Afebrile · no weight loss → Osteoid osteoma is also nocturnal and also relieved by NSAIDs, so laterality is the discriminator → night pain and relief from NSAIDs are shared by growing pains and osteoid osteoma, so check the side, not the hour
7. 7-year-old boy was diagnosed with influenza B 3 days ago now afebrile; woke refusing to walk walks on his toes both calves tender Strength normal when encouraged Knee and ankle reflexes normal · T 37.0 °C → Serum creatine kinase → tender calves with reflexes intact days into influenza: benign acute childhood myositis; an elevated CK places the problem in muscle
8. 6-year-old boy on day 4 of influenza B, now afebrile pain in both calves; walks on tiptoe calves tender; strength and reflexes normal CK (creatine kinase) elevated T 37.2 °C · urinalysis normal → Analgesics, fluids and reassurance → myositis with a normal urinalysis: analgesia, fluids and rest at home; it is self-limited
9. 8-year-old girl with influenza A and 2 days of severe leg pain both calves tender tea-colored urine Urine dipstick strongly positive for blood T 37.4 °C · 0 to 2 red cells per high-power field · CK markedly elevated → Admission for intravenous fluids and renal monitoring → a heme-positive dipstick with almost no red cells and a markedly high CK is myoglobin: rhabdomyolysis; admit for intravenous fluids and follow creatinine and potassium
10. 9-year-old boy with influenza, now afebrile pain in both calves for 2 days calves tender; strength and reflexes normal Parents ask what to give for the pain CK elevated · urinalysis normal → Aspirin → aspirin in a child with influenza risks Reye syndrome; give ibuprofen or acetaminophen
11. 6-year-old boy with 2 days of leg pain upper respiratory infection 10 days ago trouble climbing stairs, now spreading upward symmetric leg weakness; no calf tenderness No sensory level; bladder normal Knee and ankle reflexes absent · T 37.0 °C → Guillain-Barré syndrome → ascending symmetric weakness with lost reflexes after an infection is Guillain-Barré syndrome: lumbar puncture and watch breathing; myositis keeps reflexes and hurts to touch
12. 8-year-old girl with 2 months of trouble climbing stairs struggles to rise from the floor violaceous rash on both upper eyelids Scaly red papules over the knuckles CK elevated · T 37.0 °C → Juvenile dermatomyositis → weeks of proximal weakness with a heliotrope rash and Gottron papules is juvenile dermatomyositis: systemic glucocorticoids, then long-term methotrexate
13. 7-year-old girl with 4 months of aching in both calves evenings only, worse after active days pain-free days; no recent illness No calf tenderness; joints and gait normal Afebrile · no weight loss → Growing pains → episodic evening leg pain with pain-free days and a normal exam is growing pains; myositis follows influenza with tender calves, and arthritis swells joints