How does a sprain differ from a strain?
A sprain is an injury to a ligament without dislocation or fracture. Sprains are graded on the degree of ligament rupture.1
A strain is stretching or tearing of muscle fibres. Muscle strains are graded on muscle strength, the severity of dam- age, degree of swelling, bruising and function.2
What is the prognosis of an ankle sprain?
Walking is usually possible within two weeks with full function after six to eight weeks.3
What advice should I give?
Advise protection, rest, ice, compression, and elevation (PRICE) and to avoid heat, alcohol, running and massage (HARM) in the first 72 hours. For sprains, do not immobilise the joint. For strains, immobilise the muscle for first few days and consider crutches.
Which analgesia should I prescribe?
Prescribe paracetamol or NSAIDs (after 48 hours). Codeine can be added if needed.
When is an X-ray indicated?
Refer for an ankle X-ray if there is pain in the malleolar zone and one of the following: inability to bear weight; bone tenderness along the distal 6cm of the posterior edge of the fibula or tip of the lateral malleolus; and bone tenderness along the distal 6cm of the posterior edge of the tibia or tip of the medial malleolus.
Refer for an ankle X-ray if there is pain in the midfoot zone and one of the following: inability to bear weight; bone tenderness at the base of the fifth metatarsal; and tenderness of the navicular.
Refer for a knee X-ray if there is at least one of the following: age 55 years or more; tenderness at the head of the fibula; isolated tenderness of the patella; inability to flex knee 90 degrees; and inability to bear weight.
When should I refer?
Refer to A&E if any of the following are suspected: a fracture or dislocation, or damage to nerves or circulation; a tendon rupture or wound penetrating the joint; bleeding disorder, signs of septic arthritis, haemarthrosis, or large intramuscular haematoma; or a tear of more than half the muscle belly.
Refer to an orthopaedic specialist if there is diagnostic uncertainty, joint locking or delayed recovery.
Consider physiotherapy for strains.
PRICE and HARM recommendations were based on guidelines on soft tissue knee injuries. 4
NSAID use within 48 hours is not recommended because of delayed healing.5 Advice on when to X-ray is based on Ottawa ankle and knee rules.6 Referral is based on a literature review on muscle strains.2
- Reliable, evidence-based answers to real-life clinical questions, from the NHS Clinical Knowledge Summaries in association with GP.
- See www.cks.nhs.uk
1. Struijs P, Kerkhoffs G. Clinical Evidence. BMJ Publishing Group Ltd, 2007.
2. Jarvinen TA, Kaariainen M, Jarvinen M et al. Curr Opin Rheumatol, 2000. 12(2), 155-61.
3. de Bie RA, Hendriks HJM, Lenssen PT et al. Royal Dutch Society for Physical Therapy, 2006.
4. NZGG. New Zealand Guidelines Group, 2003.
5. Orchard JW, Best TM, Mueller-Wohlfahrt HW et al. Br J Sports Med, 2008. 42(3), 158-9.
6. Stiell IG, Greenberg GH, Wells GA et al. J Am Med Assoc, 1996. 275(8), 611-5.