- An ankle sprain is a stretch or tear of one or more ligaments around the ankle, most commonly on the outside of the joint.
- Sprains are graded from 1 (mild stretch) to 3 (complete tear) — treatment depends on the grade.
- Untreated or undertreated ankle sprains are the leading cause of chronic ankle instability and repeat sprains.
- Treatment includes initial protection (boot or brace), early controlled motion, and a structured PT-guided return to activity.
- Most patients are evaluated and have a clear treatment plan in a single visit.
What are ankle sprains?
An ankle sprain is an injury to one or more of the ligaments that hold the ankle joint together. The vast majority of sprains — about 85% — occur on the outside (lateral) of the ankle when the foot rolls inward (inversion), stretching or tearing the anterior talofibular ligament (ATFL) and often the calcaneofibular ligament (CFL). Less commonly, the inner (medial) deltoid ligament is injured, or the high ankle ligaments connecting the tibia and fibula (syndesmosis) are involved.
Sprains range from a mild stretch (grade 1, mild swelling and pain but no instability) to a complete ligament tear (grade 3, significant instability and inability to bear weight). Grade and severity determine treatment. The biggest mistake patients make is treating a moderate or severe sprain like a minor one — returning to activity too early often leads to chronic instability and recurrent sprains months or years later.
At Northwest Extremity Specialists, ankle sprains are one of the most common acute injuries we see. Our clinics offer on-site digital X-ray to rule out fracture, immediate boot or brace fitting, and structured follow-up rehabilitation. With proper care, the vast majority of sprains heal completely — but the first visit really matters.
See it in motion
Animations licensed from ViewMedica · Swarm Interactive
The ankle joint is stabilized by three groups of ligaments. The lateral (outside) ligaments — the ATFL, CFL, and PTFL — prevent the foot from rolling inward. The medial (inside) deltoid ligament prevents the foot from rolling outward. The syndesmotic ligaments connect the tibia and fibula just above the ankle joint and stabilize them under load. A "low" ankle sprain involves the lateral or medial ligaments; a "high" ankle sprain involves the syndesmosis and takes significantly longer to heal.
What it feels like
Ankle sprain symptoms vary by severity. Common features:
- Sharp pain at the moment of injury, often with a "pop" sensation
- Swelling on the outside (most commonly) of the ankle
- Bruising, sometimes extending down to the foot
- Difficulty bearing weight on the affected side
- A sense of instability or "giving way"
- Tenderness when pressing over the injured ligaments
- Limited range of motion of the ankle
- Persistent pain weeks after the initial injury (suggests inadequate healing)
Why it develops
Ankle sprains occur when the foot is forced into a position the ligaments cannot tolerate. Common scenarios:
- Stepping on an uneven surface (curb, pothole, rocky trail)
- Landing awkwardly from a jump (basketball, volleyball, dance)
- Twisting the ankle while running, especially around turns
- Stepping in a hole or off a step
- A direct blow to the ankle in contact sports
- High-arched foot types that predispose to rolling outward
- Prior ankle sprains that left the ligaments stretched
How we diagnose ankle sprains
An acute ankle sprain evaluation starts with a careful history (mechanism of injury, ability to bear weight, prior sprains), then a hands-on exam to test ligament integrity, range of motion, and tenderness. On-site digital X-ray is taken to rule out fracture — particularly important if there is bony tenderness, an inability to bear weight, or specific findings on exam (the Ottawa Ankle Rules guide this decision). MRI is reserved for suspected high ankle sprains, complete ligament tears in active patients, or sprains that aren't healing on schedule. Most patients leave the same day with a diagnosis, a brace or boot, and a written rehabilitation plan.
Non-surgical care
The vast majority of ankle sprains are treated non-surgically. The right approach depends on the grade:
- Initial PRICE protocol — protection, rest, ice, compression, elevation — for the first 48–72 hours
- Ankle brace or walking boot depending on severity
- Crutches for grade 3 sprains during the first week or two
- Early controlled motion (ankle circles, alphabet writing) starting as soon as tolerated
- Anti-inflammatory medication for acute swelling and pain
- Structured physical therapy program emphasizing proprioception (balance) and strengthening
- Graduated return-to-activity plan, sport-specific when relevant
- Lace-up brace for return to sport, often used for 3–6 months
Surgical care
Surgery for an acute ankle sprain is uncommon and is reserved for high-grade injuries in elite athletes, ankle sprains with associated cartilage damage, syndesmotic (high) sprains with instability, and chronic ligament insufficiency that has caused recurring sprains. The decision is made after at least 6–8 weeks of structured conservative treatment for chronic cases.
- Lateral ligament reconstruction (modified Broström procedure) for chronic instability
- Syndesmotic stabilization for high ankle sprains with instability
- Arthroscopic debridement for associated cartilage injury
- Open repair of grade 3 acute tears in selected athletes
Ankle ligament reconstruction typically involves 2–4 weeks in a cast or boot, gradual transition to weight-bearing in a boot, then athletic shoes by 8–10 weeks. Return to running is typically 3–4 months and to high-level sport is 5–6 months.
When to see a specialist
- An acute ankle sprain — see us same day if you can't bear weight or have severe pain or swelling
- A sprain that's not improving after a week of rest and ice
- Recurring ankle sprains — even minor ones — suggest chronic instability
- A sense of "giving way" in the ankle weeks or months after the original injury
- Persistent pain or swelling more than 6 weeks after a sprain
Acute ankle sprains are evaluated at any of our 8 clinics — Dr. Denny Le at Cedar Mill/Hoyt and Dr. Yama Dehqanzada at Tigard Oleson see a high volume of acute injuries. Follow-up and structured rehabilitation is handled by our sports medicine providers (Dr. Todd Galle in Wilsonville, Dr. Manny Moy at Cedar Mill) and any of our board-certified podiatrists. Surgical reconstruction for chronic instability is performed by Dr. Ron Bowman and our surgical podiatry team at Tigard Locust.