Sprains, Fractures & Dislocations

This requirement focuses specifically on the symptoms, signs, and potential complications of these three injury types. Understanding complications is critical — it’s what determines whether “wrap it and walk” is appropriate or whether the patient needs emergency evacuation.

Sprains

What it is: A sprain is a ligament injury at a joint — most commonly the ankle, knee, or wrist. See Req 8a for the full definition.

Symptoms and signs:

• Immediate pain at the joint (over the ligament, not the belly of the muscle)
• Swelling and bruising that develops over minutes to hours
• Tenderness directly over the injured ligament
• Joint instability — the joint “gives way” or feels loose
• Pain with weight-bearing or movement through the injured range
• A pop or snap may be felt at the time of injury (with Grade III sprains)

Potential complications:

• Avulsion fracture: The ligament can pull off a small piece of bone at its attachment point. This looks and feels like a sprain but is actually a fracture. X-ray is needed to rule it out.
• Chronic instability: A Grade III sprain that isn’t properly treated can result in permanent joint instability, increasing the risk of future sprains.
• Osteochondral injury: The force that sprains the ligament can also bruise or chip the joint cartilage or underlying bone.
• Compartment syndrome (rare): Severe swelling in a closed compartment (the ankle/leg) can impair circulation. Signs: severe, escalating pain; swelling that seems out of proportion; pain with passive stretching; tingling or numbness; pale or bluish toes.

Field assessment tip: If the Scout can bear weight and take four steps, it’s unlikely to be a fracture — but when in doubt, splint and transport.

Fractures

What it is: A break in bone continuity. See Req 8a for the distinction between simple and compound fractures.

Symptoms and signs:

• Point tenderness — pressing directly on the fracture site causes intense pain (distinguishes fractures from soft tissue injuries, which have more diffuse tenderness)
• Deformity — the limb may be bent or shortened
• Swelling and bruising
• Crepitus — a grating or crunching sensation when the fracture site moves
• Loss of function — the patient cannot use the limb normally
• An audible crack at the time of injury
• With compound fractures: visible bone or wound overlying the fracture

Potential complications:

• Neurovascular injury: Bone fragments or swelling can compress or lacerate nearby nerves and blood vessels. Check distal pulse, sensation, and movement (PSM) beyond the fracture — a missing pulse or numbness is an emergency.
• Compartment syndrome: Bleeding and swelling inside fascial compartments (tight tissue wrappings around muscle groups) can build up pressure, compressing vessels and nerves. Classic sign: “pain out of proportion” to the injury, particularly with passive stretching of the muscles. This is a surgical emergency.
• Bone infection (osteomyelitis): Open fractures are at serious risk.
• Fat embolism: Large bone fractures (especially the femur) can release fat into the bloodstream, potentially causing respiratory failure. More common in delayed treatment.
• Shock: The femur can contain 1–2 liters of blood in a closed fracture. Pelvic fractures can contain even more. Significant blood loss leads to hypovolemic shock.

Dislocations

What it is: Bones forming a joint forced out of normal alignment. Most common: shoulder, finger, kneecap, elbow.

Symptoms and signs:

• Visible deformity — the joint looks “wrong”
• Extreme pain, often immediately
• The joint is held in a fixed, abnormal position
• Swelling
• Complete loss of normal joint motion
• Possible numbness or tingling distal to the injury (nerve involvement)

Potential complications:

• Neurovascular compromise: The brachial artery and brachial plexus nerves run through the shoulder — a shoulder dislocation can stretch or compress them. Check PSM of the hand immediately.
• Associated fractures: Up to 25% of shoulder dislocations have an associated fracture. This is why dislocations should not be reduced in the field without training.
• Recurrence: A first-time shoulder dislocation significantly increases the risk of future dislocations, especially in young people.
• Rotator cuff tears: The force of a dislocation can tear the surrounding muscles.

If any PSM check is abnormal, this becomes an urgent evacuation — blood supply or nerve function may be compromised.

Understanding what can go wrong with these injuries prepares you for the hands-on work ahead — bandaging and splinting.