Orthopedics Flashcards
Most common causes of infection following arthroplasty by timeframe
- < 3 months: S. aureus
- 3-12 months: S. epidermidis
Patient presents with suspected vertebral osteomyelitis. MRI supports diagnosis. Blood cultures return negative. What is the next step in diagnosis?
CT guided biopsy
Broad coverage for osteomyelitis
Vancomycin + ciprofloxacin
Or more generally speaking, it should cover both Staph and S. aeruginosa
Initial empiric treatment of osteomyelitis
Narrowed osteomyelitis abx and special case management
Treatment of osteoarthritis
- Since it is not an inflammatory arthritis, medical treatment addressing the ulderlying cause is somewhat limited:
- Primarily weight loss and cessation of joint-loading activities
- Symptomatically, analgesics should be utilized when appropriate
- If the above measures fail to adequately address the problem, total arthroplasty/joint replacement is the definitive surgical therapy
Morton’s neuroma
Baker cyst aka Popliteal cyst
- Swelling in the popliteal fossa that contains synovial fluid. Produced by synovial inflammation, leading to excessive synovial fluid production.
- Sx: Mostly asymptomatic, detected on imaging. If symptomatic, swelling of the popliteal fossa and posterior knee pain are common.
- Dx: Clinical. Plain x-ray or ultrasound may be helpful. MRI if really not sure.
- Tx: If asymptomatic, no treatment necessary. If a problem, treat underlying knee pathology, intra-articular glucocorticoids. If persistant, surgical drainage/excision.
- Complications: Cyst may enlarge and rupture, leading synovial fluid into the lower leg muscles. This presentation can mimic a calf DVT.
Plantar fasciitis
- Inflammation of the plantar aponeurosis
- Etiology: Repetitive microtrauma
- Risk factors: Foot deformities, training errors (excessive training, sudden change in training rigor, inappropriate equipment)
- Most common in runners and ballet dancers
- Pres: Pain in heel and sole of foot. Worsens after periods of inactivity or prolonged weight bearing.
- Dx: Point tenderness on the sole. US shows plantar fascia thickening, edema (especially at calcaneus insertion). X-ray may show outgrowth of calcaneus bony tuberosity (heel spur).
- Tx: Plantar foot and calf stretching. Heel shoe inserts. Avoid aggrivating movements. NSAIDs, glucocorticoid injection.
Genu varum vs Genu valgum
- Etiologies:
- Varum: Normal at birth, but should correct with age. Rickets is the most classic pathologic etiology. Skeletal dysplasia (Schmid metachondreal dysplasia) or neoplasm are also possible.
- Valgum: Normal at 2-5 years, but should correct with age. Post-traumatic in setting of distal femur fracture is most classic pathologic etiology. May occur due to rickets, but less common than varum. Skeletal dysplasia and neoplasm are also possible.
Greater trochanteric pain syndrome
- Etiology: Gluteus medius or gluteus minimus tendinopathy
- Common cause of lateral hip pain, generally localized to the greater trochanter at the proximal tibia with tenderness to palpation
- Dx: X-ray to rule out other etiologies (osteoarthritis, femoral neck fracture). US may show thickening of the iliotibial band.
- MRI necessary to prior to surgery to visualize anatomy.
- Tx: Mainly conservative. Physical therapy, joint rest. Oral NSAIDs and glucocorticoid injections for pain. In cases that do not respond to conservative management for > 12 months, bursectomy is indicated.
Monteggia forearm fracture
- Common in kids
- Tx:
- Kids w/ uncomplicated fracture: closed reduction, casting
- Adults or complicated fracture: open reduction and internal fixation
Galeazzi forearm fracture
- Common in kids
- Tx:
- Kids w/ uncomplicated fracture: closed reduction, casting
- Adults or complicated fracture: open reduction and internal fixation
Prepatellar bursitis
- Etiology: often caused by overuse injuries (excessive kneeling) or repeated trauma to the knee
- Professions which require frequent kneeling (e.g., carpet installers, masons, plumbers, mechanics) are especially prone to developing prepatellar bursitis.
- Tx: Treatment is conservative and involves rest, ice or heat, elevation, NSAIDs, and, in case of infection, antibiotics.
Psoas abscess
- May present as:
- apparent appendicitis without an inflammed appendix,
- appendicitis presentation on the left,
- or apparent pyelonephritis with CVA tenderness but negative urinalysis
- Dx: CT or MRI to visualize abscess
- Tx: Drainage, abx
Patellofemoral pain syndrome
- Most common in young female athletes
- Pain produced specifically with pressing of patella into femur is a specific sign
Mallet finger
- Etiology: Finger trauma, rupture of extensor digitorum tendon
- Uncomplicated if no associated displaced fractures, extension deficit < 45°
- Tx:
- Uncomplicated: a stack splint is used to stabilize the joint for 6–8 weeks in slight hyperextension position, to achieve close approximation of the tendon ends and full recovery.
- Complicated: Surgical repair
Jersey finger
- Etiology: Flexor digitorum profundus tendon rupture
- Pain and swelling of DIP, loss of DIP flexion
- Tx: Always surgical w/ tendon repair
Finger tendons
Boutonierre deformity
- Etiology: Slippage/disruption of the central band of the extensor digitorum tendon (same tendon as in Mallet finger). May be due to trauma or rheumatoid arthritis
- Tx:
- Conservative: Generally for trauma. Splint the finger in extension
- Surgical repair: For chronic deformity, as in RA
Gamekeeper’s thumb aka Skier’s thumb
- Etiology: Break of the insertion point of the the ulnar collateral ligament of the thumb
- Characteristically weak grip due to inability to provide oppositional thumb force
- Tx:
- Conervative: Thumb spica / splint
- Surgical repair: For persistent deformities
Skier’s thumb x-ray
Clavicular fracture management
-
Uncomplicated (no gross deformity, no skin penetration, in place):
- Simple shoulder sling for 4-6 weeks. Physical therapy after 2-4 weeks.
-
Complicated (gross deformity, skin penetration, displaced):
- Open reduction and interal fixation. May require clavicular plate if displaced, open fracture, or evidence of neurovascular injury.
Clavicle bony anatomy
Anatomical snuffbox
Finkelstein test
Tests for De Quervian’s tenosynovitis, an overuse injury of the tendon
Antalgic gait
Treatment of osteomyelitis
Why does TB have a prediliction for upper lung lobes and bones? What do these have in common?
TB is highly aerobic
It loves the highly oxygenated upper lobe and the highly perfused bone
LE pulse exam
tPA takes. . .
. . . time to work
So, if a limb is acutely at risk (motor deficits), surgical embolectomy is the therapy of choice
Mechanical low back pain
- 2nd most common complaint in all of ambulatory medicine
- Common back pain experienced by many adults
- 2/3 of all people will have at least one episode in their lifetime
- Most will have spotaneous resolution within 2-4 weeks
Lumbar disk herniation
-
L5-S1 herniation with S1 compression:
- 40-50% of cases
-
L4-L5 herniation with L5 compression:
- 40% of cases
-
L3-L4 herniation with L4 compression:
- 10% of cases
Cauda equina syndrome vs conus medullaris syndrome
Presenting neurologic exam for compression of lumbosacral nerve roots
Pain associated with herniated lumbar disk is exacerbated by:
- Straight leg raise
- Sitting
- Valsalva
Therapy for carpal tunnel
-
Conservative:
- Modification of activities
- Night-time splint application
- NSAIDs
- Corticosteroid injections (take a long time to work, not terribly effective)
-
Second-line (only after trying conservative for 4 months):
- Carpal tunnel release surgery (cutting of the transverse carpal ligament)
Arm nerve compression syndromes
- Carpal tunnel: Median nerve
- Cubital tunnel: Ulnar nerve
- Saturday night palsy: Radial nerve
Phalen’s test
Durkan’s compression test
Basically a more aggressive Tinel’s sign
Rather than tapping along the median nerve, you compress it for 30 seconds
Carpal tunnel anatomy
Systemic risk factors for carpal tunnel
- Diabetes mellitus
- Hypothyroidism
- Hyperthyroidism
- Acromegaly
- Pregnancy
- Rheumatoid arthritis
Patient presents with firm, nontender, non-fatty soft tissue mass in an extremity without history of recent trauma or infections. It is not in the anatomical position of a lymph node and is 6 x 5 cm. What is the most likely diagnosis?
Soft tissue sarcoma
Masses may be painful/tender if there is a component of tumor necrosis, so this should remain on the ddx for inflammatory changes in soft tissue and lymphadenopathy
May occur in individuals of any age
As a rule, patients with soft tissue sarcoma do NOT present with ___, unlike most other cancers
As a rule, patients with soft tissue sarcoma do NOT present with constitutional symptoms or regional lymphadenoptahy, unlike most other cancers
Biopsy of a mass suspicious for soft tissue sarcoma
- Core needle is a good start
- If nondiagnostic, incisional biopsy
- DO NOT perform excisional biopsy for suspected STS – there is a high frequency of positive margins
Staging of soft tissue sarcoma
- MRI or CT for local extent
- CT chest, abdomen, pelvis for distant metastases
Treatment of soft tissue sarcoma
-
Superficial local disease responds very well to simple surgical resection with negative margins with an excellent prognosis
- Goal is >2 cm uninvolved tissue margins or intact fascia around resected specimen
-
Stage II or III disease is an indication for adjuvant radiation therapy
- Adjuvant and neoadjuvant equally as effective. Neoadjuvant has benefits of lower dose and smaller surgery, however has greater post-surgical complicaiton rates
- Patients with high risk STS may derive benefit from adjuvant systemic chemotherapy
“R” grading system for tumor resection
- R0: Microscopically negative margins
- R1: Microscopically positive margins
- R2: Macroscopically positive margins
Favorable vs unfavorable features of a sarcoma at presentation
Tumor syndromes associated with sarcoma development
- Neurofibromatosis: Sarcomas of nerve structures
- Li-Fraumeni: p53 mutation, generalized risk
- Retinoblastoma: pRb mutation, osteosarcomas
- Gardner syndrome (FAP subtype): desmoids tumors
Retroperitoneal sarcomas
- Usually asymptomatic until very large (~15-20 cm)
- Symptoms are mostly compressive in nature
- Early satiety
- Lower extremity venous congestion
- Biopsy generally unnecessary due to distinct imaging characteristics, but could be considered in cases of diagnostic uncertainty
- Rarely metastasize to distant sites, but may recur locally (particularly de-differentiated sarcomas)
Risk factors for soft tissue sarcoma
- Prior history of lipoma resection does NOT increase the risk of soft tissue sarcomas in the future
- Risk factors:
- Associated tumor syndrome
- Prior history of radiation or chemotherapy
- History of smoking
Avascular necrosis in adults
Most cases of avascular necrosis in adults occur in individuals with a history of. . .
. . . >24 alcoholic drinks/wk for >8 years
Etiology of alcohol-related avascular necrosis
Likely due to fat embolism in the context of alcohol-induced dyslipidemia
When it comes to the ACL and PCL, how do you tell which is torn?
If you can move the leg more anteirorly than you should be able to, it’s the ACL (anterior drawer)
If you can move it more posteriorly, it’s the PCL (posterior drawer)
Indications for immediate limb fracture reduction
- Distal vascular compromise
- Distal neural compromise
What does closed reduction of a limb accomplish?
It re-aligns the neural and vascular components on both sides so that perfusion may be restored and the artery and nerve might heal
If neural or vascular compromise persists after closed reduction, CT angiography and emergent orthopedic surgery consult are indicated
“Comminuted” fracture
A comminuted fracture is a break or splinter of the bone into more than two fragments. Since considerable force and energy is required to fragment bone, fractures of this degree occur after high-impact trauma such as in vehicular accidents.
Indications for cervical spine imaging in trauma
- Neurologic deficit
- Spinal tenderness
- Altered mental status
- Intoxication
- Presence of a distracting injury
The presence of a single spinal fracture in the setting of trauma is an indication to. . .
. . . image the entire spine
Ddx for heel pain
Ganglion cysts
Features of Charcot Joint
Non-pharmacologic, non-surgical intervention for knee osteoarthritis
Quadriceps strengthening exercises
Reduces the load on the joint.
Fat embolism syndrome
- Triad of respiratory distress with patchy infiltrates on CXR, neurologic dysfunction/delirium, and petechial rash.
- Petechial rash not always present
- Commonly after femur or pelvis fractures/repair
“Hard” and “Soft” signs for surgical management of clavicular fracture
Drop arm test
For complete supraspinatus tears
Quadriceps tendon tear
- Caused by sudden, forceful quadriceps contraction
- Low-riding patella and palpable defect above the patella
- Accompanied by audible pop, rapid and large swelling, and inability to extend knee
“Absent foot plantarflexion in response to calf squeeze”
Buzz phrase for Achilles tendon rupture
Femoral nerve
In every case of knee dislocation, you need to obtain __ to check __
In every case of knee dislocation, you need to obtain an ABI to check the popliteal artery
Even if you can palpate a distal pulse
Giant cell tumor
- Characterized by “soap bubble appearance”
- Benign, but locally destructive tumor
- Occurs in epiphyses of long bones
- Treatment w/ surgical excision is first-line. Denosumab (anti-RANKL) may also be used to shrink tumors.
Ruling out cervical spine injury requires. . .
. . a CT scan.
Not an X-ray. X-ray is not sensitive enough.
Buckle fracture
Occur in young kids whose growth plates are still active
Rather than breaking when exposed to blune trauma, the bone may “buckle” instead, without breaking or displacing.
Treatment involves pain control and splinting.
Imaging findings of avascular necrosis of bone
NOT SEEN on X-rays. Don’t let a normal X-ray fool you into thinking that a bone is okay.
MRI is the best imaging test for detection. “Crescent sign” may be visible in late stages.
Plantar puncture-induced osteomyelitis should make you strongly suspicious of. . .
. . . Pseudomonas
Even in a totally healthy person. These conditions are just optimal for pseudomonas infection.
Osteomyelitis empiric coverage in kids
Myositis ossificans
Greenstick fracture
- When the periosteum (which is strong in children) contains a fracture
- Opposite side to break will often be “bent” rather than broken
- Treat with immobilization to prevent complete breakage. Follow-up with X-rays until resolved.
- No long term complications are expected
Ottawa Ankle rules
Lateral ankle sprains
Sprain that occurs when you accidentally step on the alteral aspect of your foot!
The anterior talofibular ligament is most commonly injured. Follow the Ottawa rules for management. Will treat with conservative management if no X-ray is required.
