Epidemiology of Ankle Sprain

• 1/10,000 persons/day
• 23,000 ankle sprains in the U.S. each day
• 40-45% of sports injuries are ankle injuries. 85% of ankle injuries are sprains. 85% of sprains are due to inversion with injury to the lateral ligaments.
• Basketball players account for 50% of ankle sprain

Anatomy

• Ankle stability is an interplay between osseous constraints and ligamentous support
• Osseous constraints: shape of the talus and its tight fit between the tibia and the fibula.
• Ligamentous constraints: tibiofibular ligaments, deltoid ligament complex, and lateral ligament complex.
  

Lateral Ligaments

• ATFL (anterior talofibular ligament)
• CFL (calcaneofibular ligament)
• PTFL (posterior talofibular ligament)

ATFL

• Origin: fibula Insertion: talus
• Runs parallel to the foot in ankle dorsiflexion
• Runs palallel to the leg in ankle plantarflexion
• Most commonly injured ligament in inversion ankle sprain since most sprains occur when the foot is in plantar flexion.

CFL (calcaneofibular ligament)

• Origin: fibula Insertion: calcaneous
• Runs almost parallel to tibia when the foot is in dorsi flexion
• Forms the floor of the peroneal tendon sheet. Clinically relevant in diagnosing CFL rupture on ankle arthrography and peroneal tenography.

PTFL (posterior talofibular lig.)

• Origin: fibula Insertion: posterior talus
• Strongest ligament of the three lateral ligaments.
• Rarely injured
• PTFL tear occurs only in combination with ATFL or CFL tear

Deltoid Ligament

• Triangular fan shaped attaching the medial malleolus to the navicular, the calcaneous, and the talus.
• Injury occurs with foot pronation, external rotation, and abduction.
• Only 3% of ankle sprains involve the deltoid ligament.
• Complete tear is almost always associated with ankle fractures.

Tibiofibular syndesmosis

• Consists of:
  • AITF (anterior inferior tibiofibular lig.)
  • PITF (posterior inferior tibiofibualr lig.)
  • Interosseous membrane
• Function:
  • Prevent lateral displacement of the fibula resulting in a widened mortis.
  • Control external rotation and posterior displacement of the fibula with respect to the tibia

Classification of Injuries

Stability exam

• Anterior Drawer test:
  • Test for the ATFL
  • Brostrom and Linstrand: negative drawer test under anesthesia excludes ATFL rupture
  • Halmilton: best predictor of instability and dysfunction.
• Talar Tilt test:
  • Test for the CFL

Treatment

• Early immobilization with active rehab
• Long term disability for early immobization is no different than cast immobiliztion
• Results of primary repair is contradictory.
• Late repair yields excellent results.
• Degree of instability does not change the management of ankle sprain or long term disability
• For additional information on treating injured ankles. Visit theathlete.org.

Chronic Ankle Pain

• Patient Profile
  • Previous injury of weeks to months
  • Activity limiting pain described as "soreness"
  • Generalized "weakness" with locking, giving way, and swelling
  • Frustrated and often hostile

Differential Diagnosis

• Incomplete rehabiliation/Reflex Sympathetic Dystrophy (RSD)
• Previously undetected trauma or anatomic disruption
• Inflammatory disorder
• Congenital abnormality
• Unrecognized neoplasm

Differential Diagnosis

• Persistently weak and/or easily fatigable muscles about the ankle joint
• Capsulitis results in a restricted ROM
• Pinching or inflamed tissue between the talus and fibula that results in a meniscoid tissue development in the ankle
• Post traumatic arthritis

Shrier vs. Grana

• Improper rehab may result in instability which can cause pain.
• Post traumatic inflammation and resulting impingement. Both believe in postraumatic arthritis in ankle sprain.

Improper Rehab

• Premature return activity may delay healing and perpetuate residual inflammation. Advocates "hop stress test" as indication to return to activity.
• Inadequate rehab (stretching and strengthening) can provoke an abnormal sympathetic response
• Weak muscles that are worked beyond point of fatigue can place excessive stress on ligaments which can create pain.
• Improper Rehab theory --> urrrrgh!!
• Jacobson: "inadequate immobilization and rehab lead to chronic inflammation resulting in scar tissue…then becomes trapped between the talus and lateral malleolus causing irriation and synovitis…end result is chronic ankle pain"
• Not aware of any study that shows increase morbidity with repeated sprains or early return to activities.

Previously Undetected Trauma

• Lateral talus, anterior calcaneous process, lateral cuboid, fifth metatarsal fractures.
• Peroneal tendon dislocation and subluxation
• Syndesmotic ligament injuries
• Osteochondriitis dissecans

Inflammatory Disorders

• Anterior tibia and talar neck osteophytes
• Posterior synovial inflammation with impingement of hypertrophied synovium or pathologic labrum.
• Anterolateral synovitis or impingement from adhesion in the talomalleolar joint, ie, "meniscoid" like lesion

Congenital Abnormalities

• Tarsal Coalition
• Accessory navicular

Tumor

• Simple cysts
• Osteoid osteomas

My Differential Diagnosis

• Instability
• Missed Fractures
• Syndesmosis Diastasis and Synostosis
• Osteochondritis Dissicans
• Anterior and Posterior Tibiotalar Impingement
• Sinus Tarsi Syndrome

Instability

• Isolated medial instability does not exist
• Must rule out peroneal weakness
• Patients complain of recurrent ankle sprain, pain, swelling, giving way, and inability to attain pre-injury activity.
• Diagnosed mainly by history, physcial exam, and exclusion of other causes

Instability

• Mechanical instability
  • 120 patients with complaints of instability
  • Anterior talar translation of 10mm or more
  • Talar tilt of 9 degrees
  • Side to side difference of 3 mm and 3 degrees
• Other authors have found no correlation between mechanical and functional instability

Mechanical Instability

• Anatomic repair:
  • Brostrom: 90% good short and long term
• Non-anatomic reconstruction:
  • Evans: 50% good long term result
  • Watson-Jones: 30-80% good long term result
  • Chrisman&Snook: 90% good long term result

Arthritis

• Long standing lateral ligament instability may possibly cause degenerative arthritis
• Of 36 patients with 10 year history of instability, 26 had degenerative changes on X Ray, 24 had chronic synovial thickening.
• 12 arthoscopies showed extensive degenerative changes.

Functional Instability

• Feeling of giving way without laxity on exam
• Freeman 1965: motor incoodination due to capsular deafferentation, lack of proprioception that is treatable with coordination exercises and ankle tilt board.
• Treatment: peroneal strengthening, taping, bracing, and proprioceptive training.

Missed fractures

• Proximal fibula
• Lateral or posterior process of the talus
• Anterior process of the calcaneus (calcaneal attachment of the ligaments)
• Fifth metatarsal (insertion of peroneus brevis)
• Navicular and mid metatarsals
• Epiphyseal separation in children

Syndesmotic Injury (DTFS)

• 18% of ankle injuries in football players have DTFS sprain
• DTFS is stabilized by four ligaments
• Mechanism of injury is forced external rotation of the foot with simultaneous internal rotation of the leg.
• Diagnosed by history and physical exam: point tenderness, squeeze test, Cotton test
• Rule out fractures since isolated syndesmotic rupture is rare.

Syndesmotic Injury

• Stiehl 1990: diagnostic criteria
• Treatment:
  • Partial isolated sysdesmosis tears without fractures or tibiofibular/joint space widening should be treated consevatively
  • Complete tear requires surgery, suture repair of the ligaments and fixation of tibia and fibula with screw or wire.
• Inadequate treatment of syndesmotic injury will result in instability, pain, and arthritis

Tibiofibular synostosis

• Partial of complete ossification of the syndesmosis as the result of hematoma formation.
• Pain during push off phase of running 3-12 months after ankle sprain.
• Limited dorsiflexion on exam
• Surgical excision recommended for symptomatic high level athletes

Osteochondritis Dissicans

"They wanted to interview me before signing me to endorse the product…I told them I had never eaten Wheaties and didn't know I'd even like Wheaties…eat some kind of wheat puffs when I was growing up."

Anterior impingement

• Morris and McMurray described osseous exostoses of the anterior rim of the tibia and the sulcus of the talus.
• Thought to be secondary to traction injury of the joint capsule occuring when the foot was in extreme plantar flexion
• Others thought it was due to repetitive dorsiflexion trauma resulting in ossification.
• These can be seen on plain X-Ray

Anterior Impingement

• Ligamentous impingement caused by the distal fascicle of the normal anteroinferior tibiofibular ligament.
• Seven patients with anterior ankle pain after inversion injuries. None had osseous exostoses.
• Severe pain in anterior ankle especially in dorsiflexion
• At surgery, all had thickened distal fascicle.
• All had excellent to good result with resection at 2-6 year follow up.

Posterior Impingement

• Chronic posterior ankle pain and swelling after repeated sprains with normal exam and Xray
• On arthroscopy: soft tissue mass at posteriornedial capsule. Plantarflexion and inversion causes impingement of mass between posterior talus and tibia.
• Symptom free one year after surgery
• Reported cases of os trigonum in dancers

Sinus Tarsi Syndrome

• Pain and tenderness ove the lateral opening of the sinus tarsi.
• 70% cases involve severe inversion sprain. 
  30% other inflammtory disorders.
• Pain in lateral side of foot over the opening of the sinus tarsi.
• Pain is severe when standing, walking on uneven ground, supination--resolves with rest/pronation.
• Pain is thought to be from low grade inflammatory synovitis from sprain of the interossus ligament within the sinus tarsi.

SST - Treatment

• Komparda: 2/3 of patients will respond to repeated injections (once/week x 5-6). Also rec'd re-education of the peroneal and calf muscles through strengthening exercises.
• Kuwada:
  • 22/88 patients responded with injections.
  • 66/88 were cured with sinus tarsectomy.
• Others are not as successful. Arthrodosis as last resort

Summary

• Instability
• Missed Fractures
• Syndesmosis Diastasis and Synostosis
• Osteochondritis Dissicans
• Anterior and Posterior Tibiotalar Impingement
• Sinus Tarsi Syndrome
• Congenital/tumor
• Examine the foot!

 

 

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