Musculoskeletal
Compartment Syndrome
Susan K. Emerson
Background/Definition
Osteofascial compartment pressure rises to a level that decreases perfusion to the tissue in the closed fascial space.
May lead to irreversible muscle and nerve damage.
May occur anywhere that the skeletal muscle is surrounded by fascia, but most commonly occurs in leg, forearm, hand, foot, thigh, buttock, shoulder, and paraspinous muscles.
Compartment syndrome is a medical emergency.
Etiology/Types
Trauma.
Fractures (majority of cases).
Crush injuries.
Contusions.
Gunshot wounds.
Tight casts, dressings, or external wrappings.
Extravasation of intravenous (IV) fluids/medications or intraosseous infusion.
Burn injuries.
Post ischemic swelling (e.g., reestablished blood flow after blocked circulation).
Bleeding disorders.
Pathophysiology
Local trauma and soft tissue destruction → bleeding and edema → increased interstitial pressure → vascular occlusion → myoneural ischemia.
Fascia does not stretch, resulting in increased pressure on other structures in the compartment (e.g., capillaries, nerves, and muscles).
Clinical Presentation
The five P’s (not always all together and not always reliable).
Pain with passive stretch.
Pain out of proportion to clinical situation.
Paresthesia.
Paralysis.
Pulses absent.
In children, the three A’s may precede the five P’s by several hours.
Anxiety (increasing).
Agitation.
Analgesic requirement.
Diagnostic Evaluation
Measurement of compartment pressure.
>30 mmHg typically requires fasciotomy.
Consider clinical picture in management plan.
Radiography of involved area to evaluate for fracture.
Management
Medical emergency.
Institute therapeutic management while awaiting surgical specialty evaluation.
Remove binding devices (e.g., casts, splints).
Keep extremity at the level of the heart.
Elevation or dangling of extremity may further impair blood flow.
Control pain.
Administer oxygen.
Correct hypotension, if present.
Acute fasciotomy is the definitive therapy; open all involved compartments.
Typically performed at the bedside; may be performed in operating room (OR) depending on level of urgency.
Antimicrobials may be administered to prevent surgical infection.
Use coverage for common skin pathogens (e.g., Staphylococcus aureus).
Postprocedure: close evaluation for continued compartment syndrome and signs of infection, infection prevention, and pain control.
In many cases, the wound is closed after several days or a graft is placed.
PEARLS
High index of suspicion and careful evaluation is needed for children who have suffered multiple injuries, are sedated, unconscious, or uncooperative.
Delayed diagnosis can result in increased tissue ischemia and worse outcomes.
Legg-Calvé-Perthes Disease
Dana L. Lerma
Definition
Childhood condition in which the proximal femoral epiphysis has a temporary interruption in blood supply, leading to bone necrosis and subsequent repair.
Etiology
Not entirely clear.
Potential causes include infection, inflammation, trauma, and acetabular retroversion.
Epidemiology
Most commonly affects children between 4 and 8 years of age.
More common in males.
Pathophysiology
Interruption in arterial or venous blood flow to the proximal femoral epiphysis, resulting in bone necrosis; subsequent bone repair.
Four stages of necrosis and repair.
Ischemic event leading to cessation of blood supply to the femoral head.
Fragmentation stage: Re-absorption of bone with femoral head collapse. Fractures are not uncommon in this stage.
Re-ossification phase: New bone formation.
Bone remodeling: Femoral head begins to re-shape into a spherical shape. After this stage, residual deformity can still be observed.
Clinical Presentation
Mild to moderate pain in the hip on the affected side.
Pain may radiate to the thigh or knee, most commonly.
Occasionally, pain is more severe.
Leg length discrepancy or limp may be present.
Internal rotation and abduction of the affected leg are limited.
Diagnostic Evaluation
Radiograph of the hip or pelvis is the first diagnostic approach (Figure 19.1).
MRI or bone scan may also be indicated during the early stages of the disease progression to detect changes that may be more difficult to discern on radiograph.
Management
Initial management is dependent on the extent of epiphyseal involvement.
FIGURE 19.1 • Legg-Calvé-Perthes Disease Anteroposterior (AP) Radiograph of Bilateral Hips and Pelvis. AP radiograph of bilateral hips and pelvis of patient with Legg-Calvé-Perthes disease in the right hip.
Treatment is aimed at maintaining the femoral head properly placed in the acetabulum and maintaining adequate range of motion.
Mild Legg-Calvé-Perthes disease (LCPD).
Normal activity with observation.
Severe LCPD.
Activity restriction.
Physical therapy (PT).
Possible bracing to maintain proper positioning of the femur.
Long-term management of severe cases may include:
Extensive PT and rehabilitation.
Prolonged immobilization with use of orthotics or spica casting.
Close follow-up by an orthopedic specialist.
Rarely, surgery is indicated, but in some severe cases may be beneficial.
Osteomyelitis
Susan K. Emerson
Background/Definition
Infection in the bone.
More common in children than adults because of rich metaphyseal blood supply and thick periosteum.
If untreated, may result in purulent material throughout periosteal space.
Approximately 50% of infections occur in children <5 years of age.
Can occur in any bone; however, femur and tibia are the most common sites.
Types
Acute or chronic.
Pathophysiology
Osteomyelitis may occur as a result of hematogenous spread from bacteremia, local infection from a contiguous infection, or from direct inoculation from trauma or surgical procedure.
Risk Factors
Hemoglobinopathies (e.g., sickle cell disease).
Chronic renal disease.
Type 1 diabetes.
Compromised immune system.
Etiology
Staph. aureus is the most common organism in children (except neonates), 70% to 90% of infections.
Community-acquired methicillin-resistant Staph. aureus (MRSA) is becoming more prevalent.
Other offending organisms include group A hemolytic streptococcus, Streptococcus pyogenes, Strep. pneumoniae.
Group B streptococcus is the most common organism in neonates.
Pseudomonas is associated with puncture wounds, especially of the foot.
Haemophilus influenzae: incidence has decreased since advent of H. influenzae vaccine.
Clinical Presentation
Depends on child’s age and bone involved.
May have history of recent injury or infection.
Discrete tenderness at site of infection in affected bone.
May be associated with erythema, warmth, and edema of affected extremity.
Limp or refusal to bear weight; lower extremity.
Refusal to use extremity; upper extremity.
Fever, chills, vomiting.
Neonates may present with irritability, change in sleep habits, and decreased PO intake.
May appear toxic if long duration of infection.
Diagnostic Evaluation
Laboratory values.
White blood cell (WBC) count is highly variable with poor correlation to treatment.
C-reactive protein (CRP) is the most sensitive marker to monitor therapeutic response. Rises more quickly (e.g., within 6 hours of infection) and declines more quickly with effective therapy.
Erythrocyte sedimentation rate (ESR) rises and declines more slowly than CRP (e.g., elevated within 24-48 hours).
Blood cultures are positive in approximately 50% of cases and become negative soon after appropriate therapy is initiated.
Radiography.
Plain radiograph.
Early radiographs are often normal or demonstrate soft tissue edema.
Late radiographs (e.g., 1-2 weeks) demonstrate metaphyseal reaction and possibly an abscess (Figure 19.2).
MRI.
Highly sensitive and specific.
Demonstrates bone and soft tissue reaction.
Can assist in identifying associated abscess.
Differentiates between soft tissue and bone infection.
Imaging study of choice in patients with focal symptoms and strong suspicion of diagnosis.
Computed tomography (CT).
Identifies abscess and areas of destruction.
Ultrasound.
Maybe helpful in evaluating for abscess; though unable to image details of the bone.
Management
Nonoperative.
Indicated in early disease or disease without abscess.
Antibiotics should be started intravenously once a biopsy/culture has been obtained.
IV antibiotics provide optimal bactericidal levels in the affected bone and reduce dissemination of disease.
FIGURE 19.2 • Classic Osteomyelitis Anteroposterior (AP) Radiograph of Ankle. AP view of the ankle in a child with classic osteomyelitis. There are lytic areas in the fibular metaphysis with periosteal new bone formation. The epiphysis is normal.
Empiric antibiotics should include coverage for Staph. aureus (e.g., oxacillin or first-generation cephalosporins). If MRSA is suspected, select vancomycin, linezolid, or clindamycin.
May require peripherally inserted central catheter (PICC) line placement.
Transition to oral antibiotics once patient is afebrile and ESR and CRP have normalized; may require long-term IV antibiotics (e.g., 6-8 weeks).
Consider diagnostic imaging to evaluate for deep vein thrombosis (DVT) in patients with MRSA infection and in patients requiring a long hospital stay, admission to the intensive care unit, or surgical intervention.
Consultation with orthopedic surgeon, infectious disease specialist, and occupational/physical therapist.
Operative treatment.
Indications.
Abscess on radiographic study.
Failure to respond to antibiotics.
Purulent drainage on aspiration.
Chronic infection.
Removal of abscess/purulent drainage.
IV antibiotics: may require PICC line placement for long-term IV antibiotics.
Transition to oral antibiotic when patient is afebrile and ESR and CRP have normalized.
Consider diagnostic imaging to evaluate for DVT.
Consultation with orthopedic surgeon, infectious disease specialist, and occupational/physical therapist.
