Subtalar Dislocation: Foot Dislocation Below the Ankle

Quick answer

A subtalar dislocation is a serious injury in which the foot is forced out of alignment below the ankle joint. The talus remains in the ankle mortise (the socket between tibia and fibula), but the calcaneus and the rest of the foot shift relative to it. About 80% of cases are medial dislocations (foot displaces inward, “basketball foot”) and 20% are lateral. It’s an orthopedic emergency that requires urgent reduction.

Why it happens

Subtalar dislocations require high-energy trauma. Common mechanisms include:

• Landing from a jump with the foot inverted — basketball is the classic context (hence “basketball foot”)
• Falls from height — onto the inverted or everted foot
• Motor vehicle accidents — pedal strikes, footwell trauma
• Severe sprains in vulnerable patients (rare but reported in low-energy trauma)

The foot’s stabilizing ligaments (talocalcaneal, talonavicular) tear under the load.

How to recognize it

• Obvious deformity at the back of the foot — the foot looks shifted relative to the ankle
• Severe pain and inability to bear weight
• Significant swelling, often with bruising
• Tense, stretched-looking skin over the prominent bones
• Limited or absent foot motion
• Risk of skin compromise — the dislocation can stretch the skin to the point of breakdown if not reduced quickly

Why it’s an emergency

Beyond the injury itself, untreated subtalar dislocations can cause:

• Skin necrosis from stretched skin
• Neurovascular compromise — pressure on nerves and arteries supplying the foot
• Avascular necrosis of the talus or other bones
• Permanent loss of subtalar motion if reduction is delayed

Same-day reduction is essential.

Diagnosis

• Clinical exam — the deformity is usually obvious
• X-rays — confirm the direction of dislocation (medial vs lateral) and identify associated fractures
• CT scan — typically obtained after reduction to identify occult fractures, especially of the talus or navicular. About 50% of subtalar dislocations have associated fractures
• MRI — sometimes used in follow-up to assess soft tissue and cartilage injury

Treatment

Emergency reduction

• Closed reduction under sedation or anesthesia — gentle traction with manipulation to restore alignment. About 80–90% of subtalar dislocations reduce closed
• Open reduction — required when closed reduction fails (often because soft tissue or bone fragments are interposed in the joint). Reasons for irreducibility include trapped peroneal tendons, posterior tibial tendon, navicular fracture fragments, and joint capsule
• After reduction: CT scan to check for fractures
• Splint or cast for 4–6 weeks of non-weight-bearing

Surgery

Indicated when:

• Closed reduction fails (irreducible dislocation)
• Significant associated fractures need fixation
• The dislocation is unstable after reduction

Procedures address the specific findings — fixation of associated fractures, sometimes ligament repair.

Recovery

• Non-weight-bearing in cast or boot for 4–6 weeks
• Progressive weight-bearing with rehab over the following 6–12 weeks
• Physical therapy for range of motion, strength, and proprioception
• Return to sport typically 4–6 months for low-grade injuries; longer for fracture-dislocations

Long-term outcomes

Even with good initial care, long-term consequences are common:

• Subtalar arthritis develops in 50–70% of cases over years
• Decreased subtalar motion is typical
• Chronic pain in a meaningful subset of patients
• Avascular necrosis of the talus in fracture-dislocations

Patients should be followed for years and counseled about these risks.

Bottom line

Subtalar dislocation is a high-energy injury that requires immediate care. Most can be reduced closed; some need surgery. The injury itself usually heals, but long-term arthritis is common and patients should be aware. Anyone with a deformed foot after a fall or sports injury needs emergency evaluation.