Syndesmotic Sprain

Lower Limb

Overview

A syndesmotic sprain involves injury to the syndesmotic ligaments that stabilize the distal tibiofibular joint, typically occurring from external rotation or dorsiflexion mechanisms. These injuries are often more severe and have longer recovery times than lateral ankle sprains due to the critical stabilizing role of these ligaments. High ankle sprains represent 10% of all ankle injuries but account for significant functional impairment and prolonged time away from sport.

Pathophysiology

The syndesmosis consists of the anterior tibiofibular ligament (ATFL), posterior tibiofibular ligament (PTFL), and the interosseous ligament, which maintain the tibiofibular mortise for ankle stability. Injury typically results from forced external rotation of the foot relative to the tibia or excessive dorsiflexion combined with rotation, causing ligamentous tearing and potential separation of the fibula from the tibia. Syndesmotic injury disrupts the load-bearing mechanics of the ankle, creating chronic micromotion and delayed healing due to poor vascularity of the ligaments.

Patient Education

Syndesmotic sprains require longer recovery (8-12 weeks minimum) compared to ankle sprains, and early aggressive mobility can worsen outcomes; gradual progressive loading under professional guidance is essential.

Typical Presentation

Site

High ankle region, specifically over the anterior and posterior tibiofibular joint space; pain above the ankle mortise rather than at the lateral malleolus

Quality

Sharp, stabbing pain; feeling of instability or 'giving way' during weight-bearing; often described as deeper pain than typical ankle sprains

Intensity

Moderate to severe; typically 5-8/10 at rest, increasing to 7-9/10 with weight-bearing and rotational activities

Aggravating

Walking and running, particularly on uneven surfaces; external rotation movements; dorsiflexion with rotation; pivoting activities; prolonged standing; climbing stairs

Relieving

Rest and elevation; ice application; ankle immobilization; non-weight-bearing positions; gentle active range of motion within pain-free ranges

Associated

Swelling over anterior tibiofibular ligament; tenderness to palpation above ankle joint; difficulty performing single-leg stance; possible fibular head pain; restricted dorsiflexion; positive squeeze test (pain with medial-lateral compression of tibia and fibula)

Orthopaedic Tests

Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.

Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).

No accuracy study

Squeeze Test (Calf Compression Test)

Procedure

Patient seated or supine. Squeeze the tibia and fibula together at mid-calf level.

Positive Finding

Pain felt down at the front of the ankle, between the tibia and fibula, rather than in the calf.

Sensitivity / Specificity

—/88% (87 ankle sprains)

Interpretation

A positive test supports a syndesmosis ('high ankle') sprain, but it misses many. Combine it with the external rotation test, tenderness over the anterior tibiofibular ligament and difficulty hopping. Suspected syndesmosis injury needs imaging, as some need surgery. From 87 people with an ankle sprain seen within 2 weeks, with MRI as the reference (Sman 2015). Only the figure reported in the abstract is shown; the other half of the pair is in the full text, which has not been read. No single test was accurate enough on its own; the authors recommend combining sensitive tests (inability to hop, ligament tenderness, dorsiflexion–external rotation) with specific ones (pain out of proportion, squeeze test).

Sources

No accuracy study

External Rotation Stress Test (ER Test)

Procedure

Patient seated with the knee bent to 90° and the ankle in neutral. Stabilise the lower leg and turn the foot outwards (external rotation).

Positive Finding

Pain over the front of the syndesmosis, above the ankle joint.

Sensitivity / Specificity

71% (87 ankle sprains)/—

Interpretation

Supports a syndesmosis injury, especially with tenderness over the anterior tibiofibular ligament. From 87 people with an ankle sprain seen within 2 weeks, with MRI as the reference (Sman 2015). Only the figure reported in the abstract is shown; the other half of the pair is in the full text, which has not been read. No single test was accurate enough on its own; the authors recommend combining sensitive tests (inability to hop, ligament tenderness, dorsiflexion–external rotation) with specific ones (pain out of proportion, squeeze test). The study used the dorsiflexion–external rotation version of this test.

Sources

No accuracy study

Fibular Translation Test

Procedure

Patient supine or side-lying. Hold the lower tibia steady and glide the lower fibula, just above the lateral malleolus, forwards and backwards.

Positive Finding

Pain at the syndesmosis, or more movement than on the other side.

Interpretation

Tests the distal tibiofibular joint. Gliding at the fibular head tests a different joint (the proximal tibiofibular joint) and is not relevant here. Not well studied.

Further reading

No accuracy study

Palpation of the Syndesmotic Space

Procedure

Palpate the anterior tibiofibular ligament just above the front of the ankle joint, and measure how far up the leg the tenderness extends.

Positive Finding

Tenderness over the anterior tibiofibular ligament, sometimes extending up the leg.

Sensitivity / Specificity

92% (87 ankle sprains)/—

Interpretation

Tenderness here supports a syndesmosis injury. Tenderness extending far up the leg suggests a more severe injury, and tenderness at the fibular neck may be a Maisonneuve fracture and needs an X-ray. From 87 people with an ankle sprain seen within 2 weeks, with MRI as the reference (Sman 2015). Only the figure reported in the abstract is shown; the other half of the pair is in the full text, which has not been read. No single test was accurate enough on its own; the authors recommend combining sensitive tests (inability to hop, ligament tenderness, dorsiflexion–external rotation) with specific ones (pain out of proportion, squeeze test).

Sources

Performance measure

Single-Leg Hop Test

Procedure

If walking is comfortable, ask the patient to hop gently on the affected leg.

Positive Finding

Unable to hop, or pain at the front of the ankle with hopping.

Interpretation

Difficulty hopping after an ankle injury raises concern for a syndesmosis injury or fracture. Do not test hopping if the Ottawa ankle rules suggest an X-ray is needed. A literature search (Europe PMC, September 2026) found no study reporting the diagnostic accuracy of this test, so no figure is shown.

Sources

⚠ Red Flags

  • •Severe swelling with skin tension or compartment syndrome signs (severe pain with passive stretch, paresthesias, pallor)
  • •Fracture of tibia, fibula, or medial malleolus visible on imaging
  • •Neurovascular compromise (absent pedal pulses, cold foot, severe paresthesias)
  • •Persistent severe pain disproportionate to clinical findings suggesting complex regional pain syndrome
  • •Open wound or break in skin integrity

⚡ Yellow Flags

  • •Multiple previous ankle injuries with persistent instability suggesting proprioceptive deficit or kinesiophobia
  • •Significant fear-avoidance behavior limiting rehabilitation participation
  • •Delayed healing response suggesting poor compliance or underlying metabolic factors
  • •Competitive athlete with unrealistic early return-to-sport expectations
  • •High catastrophizing beliefs about re-injury risk
  • •Secondary gain factors related to time away from work or activity

Osteopathic Techniques

Grade 1 syndesmotic injuries are managed conservatively: 1–3 weeks of immobilisation, then a gradual return to activity. Stable grade 2 injuries can also be managed conservatively, though most surgeons favour fixation; grade 3 injuries need surgical reconstruction. No trials of osteopathic techniques were found.

Safety: Syndesmotic injuries are commonly associated with ankle fractures, so apply the Ottawa ankle rules and confirm the joint is stable before treating. High ankle sprains are less common than lateral sprains but carry more morbidity.

Region

Ankle ligaments around the distal tibiofibular joint

Technique

Soft tissue, foot and ankleNo trials found

Rationale

Soft tissue to the plantar fascia, foot muscles and the tissues around the toe joints and ankle ligaments.

How it's done & evidence

How it's done

Hands-on kneading, stroking and sustained pressure to the plantar fascia, the small muscles of the foot and the tissues around the heel and the ankle ligaments.

Evidence in Syndesmotic Sprain

Searched 25 Oct 2026: no trials of soft tissue technique in syndesmotic sprain.

Sources

Region

Ankle tender points

Technique

Counterstrain, foot and ankle tender pointsNo trials found

Rationale

Gentle indirect technique: tender points in the foot and ankle are eased by passive positioning.

How it's done, cautions & evidence

How it's done

Find a tender point in the foot, ankle or calf. Passively move the foot and ankle into the position where the tenderness and tissue tension ease most, and hold it for about 90 seconds while monitoring the point. Return slowly to neutral and re-check.

Cautions

Do not use over an acute fracture, or in a patient who cannot give feedback.

Evidence in Syndesmotic Sprain

Searched 25 Oct 2026: no trials of counterstrain in syndesmotic sprain.

Region

Ankle and foot, once stability is confirmed

Technique

Articulation, ankle and foot
Grade D
Low evidence: expert consensus or could not be verified against literature
No trials in syndesmotic sprain. In ankle sprain, joint mobilisation improved short-term dorsiflexion and balance but not pain.

Rationale

Gentle glides of the toe, midfoot and ankle joints to restore foot mobility.

How it's done, cautions & evidence

How it's done

Passive, rhythmic, low-velocity glides of the ankle (talocrural), subtalar, midfoot and toe joints, within or up to the end of the available range, often aimed at restoring ankle dorsiflexion.

Cautions

Before mobilising an acute ankle injury, check for fracture with the Ottawa ankle rules (tenderness over either malleolus), and palpate the base of the 5th metatarsal, the navicular and the midfoot for a Lisfranc injury.

Evidence in Syndesmotic Sprain

Searched 25 Oct 2026: no trials in syndesmotic (high ankle) sprain. Indirect: Weerasekara 2018 (SR/MA, ankle sprain): joint mobilisation improved weight-bearing dorsiflexion in the short term and dynamic balance immediately, with no effect on pain.

Region

Calf complex

Technique

Soft tissue, calf and lower legNo trials found

Rationale

Calf and lower-leg soft tissue is usually given alongside a loading or stretching programme.

How it's done & evidence

How it's done

Hands-on kneading, stroking and sustained pressure to the calf (gastrocnemius and soleus), the Achilles tendon and the peroneal and tibial muscles of the lower leg. In trials it was given alongside exercise, such as eccentric calf loading.

Evidence in Syndesmotic Sprain

Searched 25 Oct 2026: no trials of calf soft tissue in syndesmotic sprain.

Rehabilitation Exercises

Ankle Alphabet - Seated

Range of MotionBeginner

Gastrocnemius Stretch - Wall

StretchingBeginner

Soleus Stretch - Bent Knee

StretchingBeginner

Ankle Inversion/Eversion - Resistance Band Seated

StrengtheningBeginner

Plantarflexion and Dorsiflexion - Resistance Band Seated

StrengtheningBeginner

Double-Leg Stance on Firm Surface - Weight Shift

BalanceBeginner

Short-Foot Exercise

StrengtheningIntermediate

Single-Leg Stance on Firm Surface

BalanceIntermediate

Single-Leg Stance on Balance Pad

BalanceIntermediate

Peroneal Muscle Strengthening - Lateral Step-Ups

StrengtheningIntermediate

Balance Board Bilateral Weight-Bearing

BalanceIntermediate

Single-Leg Balance Board with Arm Movements

BalanceAdvanced

Referral Criteria

  • •Persistent severe pain and swelling beyond 2-3 weeks despite appropriate conservative management
  • •Imaging evidence of syndesmotic separation (diastasis) or associated fracture requiring surgical evaluation
  • •Failure to progress in rehabilitation despite 6-8 weeks of structured osteopathic and physiotherapy treatment
  • •Development of complex regional pain syndrome symptoms (disproportionate pain, swelling, color/temperature changes)
  • •Recurrent instability episodes or chronic functional ankle instability not responding to proprioceptive retraining
  • •Anterior ankle impingement symptoms limiting dorsiflexion despite treatment
  • •Athlete requiring accelerated return-to-sport protocol needing specialized sports medicine assessment
  • •Neurovascular compromise requiring immediate vascular surgery consultation