# Sprains, Fractures & Dislocations Part of the First Aid Merit Badge Digital Resource Guide: [Introduction & Overview](https://merit-badge.university/merit-badges/first-aid/guide/index.md) *8. Muscle & Bone Injuries* > **8c.** Describe the symptoms and signs of, and potential complications of, a sprain, a fracture, and a dislocation. 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. > **Safety First!** > > A fractured femur (thigh bone) is a life-threatening injury. The femur can bleed 1–2 liters of blood into the thigh — enough to cause severe shock without any external bleeding visible. Any suspected femur fracture requires immediate evacuation and aggressive shock prevention. --- ## 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. **Distal PSM Check** — Do this every time you splint or suspect a limb injury - [ ] **Pulse:** Is there a pulse distal to the injury? (radial pulse for arm injuries; dorsalis pedis or posterior tibial for leg) - [ ] **Sensation:** Can the patient feel a light touch or pinprick distal to the injury? - [ ] **Movement:** Can the patient wiggle their fingers or toes distal to the injury? If any PSM check is abnormal, this becomes an urgent evacuation — blood supply or nerve function may be compromised. Video: [Fractures and Dislocations](https://www.youtube.com/watch?v=sPzXAVNVJr0) --- Understanding what can go wrong with these injuries prepares you for the hands-on work ahead — bandaging and splinting. --- - Previous: [Strains, Tears & Tendons](https://merit-badge.university/merit-badges/first-aid/guide/req8b/index.md) - Next: [Bandaging Techniques](https://merit-badge.university/merit-badges/first-aid/guide/req8d/index.md)