Sprain (ligament injury)

Common sites and mechanisms

Sprains most often affect the ankle, knee (certain ligaments), wrist and thumb, but they can occur at almost any joint. Typical causes include twisting or rolling a joint during sports, a stumble or fall, or an awkward landing. Sudden, forceful movements and repetitive stress can also lead to ligament injury.

Classification and signs

Clinically sprains are graded by severity. A Grade I sprain involves mild stretching and microscopic tearing with minimal instability. Grade II is a partial tear with some joint instability and moderate pain or swelling. Grade III is a complete rupture of the ligament, often causing marked instability and severe impairment. Typical signs include pain, swelling, bruising, reduced range of motion and difficulty bearing weight.

Diagnosis

Diagnosis begins with a medical history and physical examination, including specific joint tests to assess stability. Imaging helps confirm the extent of injury and exclude fractures: X‑rays rule out bone breaks, ultrasound can visualize some ligament damage, and MRI gives detailed views of soft tissues when needed.

Treatment and recovery

Initial care commonly follows protection, rest, ice, compression and elevation (P‑RICE or RICE). Simple sprains often recover with immobilization, pain control and a progressive rehabilitation program emphasizing range of motion, strengthening and proprioception. Severe or unstable injuries may require bracing or surgical repair followed by physiotherapy. Recovery time varies from days to many months depending on grade and joint.

Prevention and long-term considerations

Prevention focuses on conditioning, balance and strength training, proper footwear or protective equipment, and cautious progression of activity. Untreated or repeatedly injured ligaments can lead to chronic instability, recurrent sprains and, in some cases, long-term joint problems. Seek medical evaluation for severe pain, inability to bear weight, obvious deformity or persistent instability.

Key distinctions

• Sprain: ligament injury (bone to bone).
• Strain: muscle or tendon injury.
• Fracture: break in the bone; requires imaging to diagnose.