Musculoskeletal Injuries and Immobilization

Musculoskeletal Injuries and Immobilization

1. Fracture, strain, sprain, dislocation — sort them first

Four things go wrong at a joint or a bone, and you need to tell them apart before you can treat them.

A fracture is the bone itself breaking. You're going to see crepitus — that's the grinding of bone ends against each other. Plus deformity, swelling, pain with movement, and sometimes false motion, where the limb bends somewhere it shouldn't.

A strain is the muscle. Something contracts wrong and the muscle stretches, tears, or rips. The patient often feels or hears a snap, the pain is sharp and immediate, and the muscle is suddenly weak. Point tenderness is extreme, right over the tear.

A sprain is the ligament, plus the joint capsule, the synovial membrane, and the tendons crossing that joint. So the swelling shows up at the joint — that's the tell. There's often a snap at the moment of injury too, and point tenderness right at the joint line. The ankles, knees, and shoulders are the joints that sprain most.

A dislocation is the joint surfaces separating completely. The deformity is obvious, the pain is severe, and the limb sits in a position it has no business sitting in.

Strain versus sprain is a definition item. The exam locks it down hard: strain is muscle, sprain is ligament. Memorize which word owns which tissue and you've closed off a whole category of wrong answers.

Here's the fact that actually runs your treatment decision, though. You cannot reliably tell a sprain or a strain from a fracture in the field. You don't have an X-ray on the ambulance. So when you can't classify it, the rule is simple: manage it as a fracture. That one instruction answers a whole family of exam items. Whenever the stem hands you an injury you can't pin down, immobilize it like a break.