• Skip to main content
  • Skip to primary sidebar
  • Skip to footer
  • General Ortho
  • Procedures
  • Spine
  • Upper Limb
  • Lower Limb
  • Pain
  • Trauma
  • Tumors
  • Newsletter/Updates
  • About Us
  • Contact Us

Bone and Spine

Orthopedic health, conditions and treatment

High Ankle Sprains or Syndesmotic Sprains

By Dr Arun Pal Singh

In this article
    • Relevant Anatomy
    • Associated Injuries with High Ankle Sprains
    • Pathophysiology
      • Different Injury Patterns
    • Clinical Presentation
      • Squeeze test
      • External rotation stress test
      • Cotton Test
      • Fibular translation
    • Imaging
      • X-rays
      • CT
      • MRI
    • Treatment of High Ankle Sprains
      • Nonoperative Treatment
      • Operative Treatment
      • Surgical Options
    • Prognosis

High ankle sprains, also known as syndesmotic sprains, are sprains of the syndesmotic ligaments that connect distal ends of the tibia and fibula. High ankle sprains [because they are located above the ankle] comprise approximately 15% of all ankle sprains. These injuries are mostly external rotation injuries

Most of these occur in conjunction with ankle fractures and rarely in isolated form.

Relevant Anatomy

[Read anatomy of ankle joint]

Lateral-view of ankle joint

Syndesmosis is made up of

  • Anterior-inferior tibiofibular ligament
    • Originates from anterolateral tubercle of the tibia (Chaput’s)
    • Inserts on anterior tubercle of the fibula (Wagstaffe’s)
  • Posterior-inferior tibiofibular ligament
    • Originates from posterior tubercle of the tibia (Volkmann’s)
    • Inserts on the posterior part of the lateral malleolus
    • Strongest component of a syndesmosis
  • Inferior transverse tibiofibular ligaments
  • Interosseous membrane
  • Interosseous ligament
    • Distal continuation of the interosseous membrane
    • Main restraint to proximal migration of the talus

The main function of the syndesmosis maintains integrity between tibia and fibula. It resists axial, rotational, and translational forces. Deltoid ligament is the medial ligament that indirectly stabilizes the medial ankle mortise.

During normal gait, syndesmosis widens 1mm during gait

Following displacement is noted when these ligaments are sectioned.

  • Anterior tibiofibular ligament – Diastasis of 2.3 mm
  • Anterior tibiofibular ligament and interosseous ligament –  Diastasis of 4.5 mm
  • All 3 ligaments – 7.3 mm

Associated Injuries with High Ankle Sprains

  • Osteochondral defects (15% to 25%)
  • Peroneal tendon injuries (up to 25%)
  • Ankle fractures
    • Distal tibia and fibula
    • 5th metatarsal base
    • Anterior process of the calcaneus
    • Lateral or posterior process of the talus
  • Deltoid ligament injury
  • Loose bodies

Pathophysiology

High ankle sprains are most commonly associated with external rotation injuries. External rotation forces the talus to rotate laterally and push the fibula away from tibia that may lead to

  • Increased compressive stresses are seen by the tibia
  • Increased risk of lateral subluxation of the distal fibula
  • The incongruence of the ankle joint articulation

The most vulnerable structure is the anterior inferior tibiofibular ligament.

Different Injury Patterns

  • Isolated Syndesmotic injury
  • Syndesmotic injury & fibular fractures
  • Syndesmotic injury + medial injury
  • Syndesmotic injury+Posterior malleolus fracture

Clinical Presentation

There would be a pain on the anterolateral aspect of ankle proximal to the anteroinferior tibiofibular ligament. The ankle would be swollen and the patient is often able to bear the weight and walk  [in contrast lateral ankle sprains are often able to bear weight]

The examination would reveal the tenderness of the syndesmosis.

Following provocative tests indicate high ankle sprain

Squeeze test

It consists of compression of tibia and fibula at midcalf resulting in pain at syndesmosis. If pain occurs, it is considered positive for syndesmotic injury.

External rotation stress test

Pain over syndesmosis is elicited with external rotation/dorsiflexion of the foot with knee and hip flexed to 90 degrees.

Cotton Test

Widening of the syndesmosis with lateral pull on the fibula

Fibular translation

Anterior and posterior drawer force to the fibula with the tibia stabilized causes increased translation of the fibula. There would be a pain with compression too (Patient dorsiflexes the foot while the examiner compresses the internal and external malleolus),

Imaging

X-rays

Bimalleolar Fracture With Ankle Subluxation With Tibifibular Diastasisor high ankle sprains
Bimalleolar Fracture With Ankle Subluxation With Tibiofibular Diastasis

Recommended views are AP, lateral, mortise view of the ankle. AP and lateral views of the leg can be also done to rule out high fibula fracture.

Optional views include stress views in external rotation and gravity stress.

For comparison, opposite ankle x-rays can be done.

The AP view would show decreased tibiofibular overlap [normal>6mm]. The mortise view would also show decreased overlap [normal >1 mm]

There would be increased medial clear space [normal <4 mm] and increased tibiofibular clear space [normal <6 mm on both AP and mortise views]

CT

CT is more sensitive than x-rays and is indicated when the x-rays are normal and there is clinical suspicion of syndesmotic injury.

CT is also useful for postoperative assessment of reduction of syndesmosis after fixation

MRI

CT is also done when there is clinical suspicion of syndesmotic injury in the presence of normal x-rays. It is a very sensitive and specific investigation for detecting syndesmotic injury.

Treatment of High Ankle Sprains

Nonoperative Treatment

Non-operative treatment consists of controlled ankle motion [CAM] boot or cast for 2 to 3 weeks.

It is used in syndesmotic sprain without diastasis or ankle instability.

The weight bearing is delayed until the patient is pain-free. Following this physical therapy program is initiated. A brace that limits external rotation is used intermittently.

The recovery period is long and can take as much as twice that of standard ankle sprain

Operative Treatment

Indications for operative treatment are

  • syndesmotic sprain without fracture with instability on stress radiographs
  • Syndesmotic sprain refractory to conservative treatment
  • Syndesmotic injury with an associated fracture that remains unstable after fixation of the fracture

Surgical Options

Syndesmosis screw fixation

  • Two 3.5 or 4.5 mm syndesmotic screws that pass from fibula to tibia and engage at least one cortex of tibia.
  • Conventionally, the ankle is held in maximum dorsiflexion to avoid overtightening
  • The patient is kept non-weight-bearing for 6-12 weeks or longer

Syndesmosis Fixation with Suture Button

  • Fiberwire suture with two buttons tensioned around the syndesmosis
  • This can be done in addition to a screw

Prognosis

Missed injuries may result in degenerative ankle arthritis.

Anatomical reduction of syndesmosis results in an excellent outcome.

Spread the Knowledge
  • 13
    Shares
  •  
    13
    Shares
  • 0
  • 13
  •  
  •  
  •  

Filed Under: Foot Ankle

About Dr Arun Pal Singh

Arun Pal Singh is an orthopedic and trauma surgeon, founder and chief editor of this website. He works in Kanwar Bone and Spine Clinic, Dasuya, Hoshiarpur, Punjab.

This website is an effort to educate and support people and medical personnel on orthopedic issues and musculoskeletal health.

You can follow him on Facebook, Linkedin and Twitter

Primary Sidebar

Orthopedics Operating room

Principles of Treatment of Fractures

It is a dictum in orthopedics that no two fractures are alike. Every fracture behaves differently from other. In the same part fractured, there could be different types of treatment depending on many factors other than fracture geometry. Treatment of fractures takes various things into consideration -age of the patient, fracture pattern, type of bone […]

spinal accessory nerve course, PD

Spinal Accessory Nerve Palsy Causes and Treatment

Spinal accessory nerve palsy often occurs due to lesions in the neck, most often due to iatrogenic reasons. The nerve is especially vulnerable in the posterior triangle of the neck owing to its long and superficial course in the posterior cervical neck. Iatrogenic spinal accessory nerve injury most commonly occurs following diagnostic lymph node biopsies […]

vertebral osteomyelitis image

Pyogenic Vertebral osteomyelitis Presentation and Treatment

Pyogenic vertebral osteomyelitis is a type of spinal infection which may result from direct trauma, the spread of infection from adjacent structures or hematogenous spread from the distant focus of infection. It can have devastating complications if untreated which could be a pathological fracture, epidural infection, and compression of the neural structures. Vertebral osteomyelitis is […]

Wedge Osteotomy

Osteotomy Procedure and Indications

An osteotomy is a surgical procedure where the bone is cut to change its length or alignment. Often the procedure is done in an attempt to correct an abnormality that has resulted from trauma or disease. The procedure is able to correct the following deformities. valgus/varus angulation anterior/posterior angulation internal/external rotation lengthening/shortening medial/lateral shift dorsal/ventral […]

sunburst-periosteal-reaction

Periosteal Reaction and Its Types

Periosteal reaction is the formation of new bone after trauma or some other pathology from the periosteum as visualized on the radiographs. The periosteum is a membrane that covers bones except in the cartilage part. Periosteal reaction is also known as periostitis. When an insult occurs, vascular proliferation and thickening of the normal periosteum occur […]

osteopetrosis of femur with fracture, Note the obliterated medullary cavity

Osteopetrosis or Marble Bone Disease

Osteopetrosis is also called stone bone or marble bone disease. It is also known by the name of Albers-Schönberg disease. It is an inherited disorder characterized by hard dense bones due to by the failure of osteoclasts to resorb bone leading to impairment of modeling and remodeling. Osteopetrosis is a rare disease. Autosomal dominant is […]

Minimally Invasive Medial Approach to Tibia

Surgical Approaches to Tibia

Surgical approaches to the tibia are named according to the site of incision and the region accessed Anterolateral Approach to Tibia Indications This incision is the classical incision for plating of tibia or open reduction of tibial fractures. The entire tibia from knee to ankle may be exposed through this incision. It mobilizes the muscles […]

Browse Articles

Footer

Pages

  • About
    • Policies
    • Contact Us

Featured Article

Tibial Shaft Fractures

Tibial shaft fractures are often the result of the high-energy injury. Sometimes they can also be insidious in onset, such as stress … [Read More...] about Tibial Shaft Fractures

Search Articles

© Copyright: BoneAndSpine.com