Ortho Flashcards
What is the presentation of fat embolism syndrome?
Resp symptoms
Neuro changes
Reddish brown petechial rash
How long after injury does fat embolism present?
24-72 hours
What are the 4 functional components of the extremity exam after trauma?
Nerves
Vessels
Bones
Soft tissues
What is the pathophysiology of fat embolism syndrome?
Embolization of fat and marrow content from fractured long bones, especially femur - affects brain and lungs most
What are the 3 nerve injury types?
Neuropraxia
Axonotmesis
Neurotmesis
What sign is a humeral shaft fracture associated with?
Radial n injury –> wrist drop
Why does open fracture require special treatment?
Communication with environment disrupts soft tissue/skin and requires special treatment due to infection risk
Why is it important to do a thorough secondary survey after trauma?
To avoid missing additional fractures
What must the XR show in any bone fracture?
Joint above and below
What constitutes an open fracture?
Soft tissue wound + fracture
In patients with femoral neck fracture, what else must we look for?
Femoral neck fracture
What antibiotics are appropriate for open fracture?
First gen cephalosporin +/- aminoglycoside
Within what time frame should open fractures be managed?
W/in 6 hour
What is the protocol for treating an open fracture?
- Antibiotics
- Irrigation and surgical debridement
- External fixation immediately if unstable
- Internal fixation is definitive
Within how long should a closed fracture be managed?
Within 2-12 hours: intramedually nailing
Why is prompt management important for closed fracture?
Reduces risk of fat embolism syndrome
What are the main surgical risks of fracture repair?
Infection
Nonunion
Nerve or vessel injury
Amputation
What is a dangerous sequela of a tibia fracture?
Compartment syndrome
What is neuropraxia?
Minimal injury to myelin, but not axon or nerve sheath
What is axonotmesis?
Myelin + axon disrupted, nerve sheath intact. Wallerian degeneration
What is neurotmesis?
Myelon + axon + nerve sheath damaged. Wallerian degeneration
What is the most important determinant of severity for open fractures?
Energy imparted to the limb
Which grades of open fractures need additional antibiotic coverage with aminoglycoside?
Grade IIIA, B, C
Why is it important to have early stabilization of open fractures?
Protect soft tissues around the injury and prevent further damage secondary to mobile fracture fragments
What is reduction?
Putting displaced bones back to normal anatomic position
Open: through surgical incision
Closed: External manipulation of limb
What are 2 main concerns with femur fracture?
- Fat embolism
- Blood loss: highly vascular: monitor for shock
What type of orthopedic fracture is at greatest risk for hemorrhagic shock?
Pelvic fractures
What is management for fat embolism syndrome?
- Ventilatory support w/ high PEEP
- Early stabilization of fractures
- Possibly steroids
What is most important step to prevent fat embolism in poly trauma patient?
Early stabilization of long bone fractures w/in first 24 hours
What to watch out for in crush injuries?
Compartment syndrome
Rhabdo leading to kidney failure
What does acute trauma to the knee with anterior knee laxity suggest?
ACL injury
If a patient can bear weight, what can we assume?
Fracture less likely
What are the key components of the knee exam?
Gait Observation Palpation ROM Joint line tenderness Neurovascular Knee maneuvers
What is the major concern with a knee dislocation?
Vasculature damage: dysvascular limb risking amputation
How do ligament and meniscal injuries differ with regard to swelling?
Ligament: immediate swelling
Meniscal: delayed swelling
What are the 2 causes of ACL injury?
Contact
Non contact: pivoting injuries
What is the unhappy triad of the knee?
MCL
ACL
Medial meniscus
What is the imaging workup for a suspected ACL injury?
- Radiograph: look for fracture, alignment/deformity, infection and tumor
- MRI to confirm
What is the treatment for ACL tear?
Individualized: conservative or surgery
What conservative management principles should every ACL patient get?
RICE: Rest Ice Compression Elevation
Which patients with ACL tear are better candidates for non-op management?
Elderly, low-demand patients
Which patients with ACL tear are better candidates for surgery?
Young, healthy people who want to return to athletics
What type of surgery is ACL surgery?
Reconstruction, NOT repair
What are the concerns after ACL surgery?
Infection
Knee stiffness
Graft failure
If a complication is present after ACL surgery, what is the principle guiding management?
Exhaust all conservative options before re-operating
What to consider in patients with recurrent fractures?
Neoplastic lesion e.g. osteosarcoma weakening the bone
What is the distribution of blood supply to the meniscus, and why is it important?
Outside-in: only 25-30% of diameter gets blood:
Red zone: gets blood
White zone: less blood flow: not repaired but debrided if necessary
What is the significance of being unwilling (vs. unable) to range the knee?
Unwilling: suspect fracture or septic arthritis
What radiographic sign is pathognomonic for ACL injury?
Segond fracture or small fleck of bone avulsed from lateral tibial plateau
What is classic presentation of SCFE?
Obese, adolescent male aged 10-16 Groin pain Painful limp Externally rotated hip Not irritable (allows ROM)
What is the thinking re: knee pain in young children?
Hip pathology causing referred knee pain
What is the pathophysiology of slipped capital femoral epiphysis?
Excess loading across the physis causes slippage of the head on the neck of the femur (epiphysis on metaphysics)
What are predisposing factors for weak physis?
Endocrine disorders
Osteodystrophy
Hypothyroid/ hypopituitarism
What is the workup for suspected SCFE?
- XR: AP and/or frog lateral view of the hip: shows displacement of proximal femoral epiphysis on metaphysis
- Rule out septic arthritis
What is the management of SCFE?
- Admit to hospital: urgent surgical pinning of the hip w/ a single screw
- Short period of protected weight bearing with crutches
What are possible complications of fixing SCFE?
- Screw too short
- Inadequate fixation
- Additional slippage
- Avascular necrosis
In a peds patient, complaint of knee pain should prompt what?
Clinical/radiographic exam of the hip
Hip pain plus history of steroid use, what to think?
Avascular necrosis of the femoral head (osteonecrosis)
What is the significance of leg length discrepancy with hip pain?
mechanical pathology: disruptions in structural integrity of the long bones of the lower limb can lead to leg length discrepancy
What to think: inability to bear weight on the hip or range motion?
Septic arthritis or unstable SCFE
What is an antaglic gait?
Limping due to pain: short stance phase on the affected limb to minimize time on the painful limb
What is Legg-Calve-Perthes disease?
Idiopathic osteonecrosis of the femoral head: ages 4-8
What are the 4 Kocher criteria to diagnose pediatric septic arthritis?
Fever > 38.5 C
Inability to bear weight
ESR > 20 mm/h
WBC > 12,000
3% with 1, 40% with 2, 93% with 3, 99% with 4
What are the classic x-ray findings of developmental dysplasia of the hip?
Subluxation or dislocation of femoral head from acetabulum
What is the classic x-ray finding of Legg-Calve-Perthes disease?
Subchondral collapse of the bone of the femoral head
What is the classic x-ray finding of SCFE?
Asymmetry o femoral head on the neck: ice cream appears to slide off of the cone
What is the treatment of Legg-Calve-Perthes disease?
Usually none: advanced disease contains the hip: casting/bracing or femoral/pelvic ostomies
What other imaging should be done to the hip if diagnosis is unclear?
MRI
Bone scan for bone pathology
What are key symptoms of carpal tunnel?
- Sensory dysthesias in median nerve distribution
- Dropping things
- Symptoms worse at night
- Job involving repetitive wrist/hand movements
What is Tinel’s sign?
Gently percussing over median nerve at carpal tunnel: positive if the patient describes an electrical shock sensation in the median nerve distribution
What is Phalen’s sign?
Patient places dorsal sides of hands against each other in maximal wrist flexion for 30-60s: positive if the patient reports new or worsening paresthesias in the median nerve distribution of affected hand
What is Durkan’s test?
Squeezing the patient’s wrist w/ direct compression over the median nerve over the carpal tunnel w/ examiner’s thumb
Test is positive if patient has new or worsening symptoms
How do we diagnose carpal tunnel?
Clinically: history and exam
If the diagnosis is unclear clinically for carpal tunnel, what is the next step?
EMG / NCS
What must we rule out with suspected carpal tunnel?
Rule out spinal disease / medical neuropathy with:
- MRI
- Labs
What are the treatments for carpal tunnel in order of 1st line first?
NSAIDs / Wrist splinting
Carpal tunnel injection
Surgical release
When is surgical release the first management option for carpal tunnel?
Thenar wasting is present
What are the important complications of carpal tunnel?
- Painful scar / neuroma
- Injury to recurrent motor branch
- Inadequate release (particularly endoscopic technique)
- Recurrence
What are important things NOT to overlook in carpal tunnel?
Myelopathy
Pancoast tumor
Treatable peripheral neuropathy
What form of carpal tunnel is an emergency?
Acute: after fracture or dislocation
What form of carpal tunnel is an emergency?
Acute: after fracture or dislocation
Which test is most sensitive for carpal tunnel?
Durkan’s Median Nerve Compression Test
How to distinguish between proximal vs. carpal tunnel median nerve compression?
Palmar cutaneous branch of median nerve: branches before carpal tunnel to innervate thenar eminence
* Typical carpal tunnel: no sensory dysthesias in thumb
What is thoracic outlet syndrome?
Compression of the lower brachial plexus: ulnar symptoms predominate, or compression of subclavian vessels between anterior and middle scalene muscles (associated often with cervical rib)
What are risk factors for carpal tunnel syndrome?
Women Obesity Pregnancy Smoking Repetitive wrist movements RA Hypothyroidism Alcoholism CKD
What are the 3 stages of median nerve compression?
1: Sensory symptoms at night
2: Symptoms also occur by day
3: Motor symptoms of weakness and/or muscle wasting