Complex Ankle Sprain

Definition

 

Simple sprain 

- injury to ATFL

- will almost always get better in 6-8/52

 

Complex sprain 

- associated injury

- suspect if patient slow to recover 

- diagnose most things on MRI

 

Symptoms

 

Instability

- clinical diagnosis 

- most will get better with appropriate physio

 

Pain

- if pain is present as well then consider other pathology

- isolated instability isn't usually painful

 

Causes

 

1.  Soft tissue

- lateral gutter fibrosis

- Bassett's ligament (thicknened AITFL)

- meniscoid / ferkel lesion

 

2.  Bony Injury

- OCD / loose body

- bone bruise

- fracture anterior calcaneum / lateral process / sustenaculum tali

 

3.  Tendon / ligament

- deltoid

- peroneal dislocation / tears

- high ankle sprain / syndesmotic injury

- sinus tarsi syndrome

- Achilles tendonitis

 

DDx

 

Soft Tissue

 

1.  Lateral gutter fibrosis

 

Ligament healing thicker than normal 

- associated scar tissue

- initial injury seemed to get better 

- ongoing pain and swelling over lateral ankle

 

Management

- arthroscopy and debride

- most will get better

 

2. Bassett's Lesion

 

Pathology

 

Primary injury to AITFL

- tear may produce laxity

- talar dome may extrude anteriorly in DF

 

AITFL

- normally thin and above level of ankle joint

- may become thickened and scarred causing lateral ankle pain and swelling

 

Diagnosis

 

Difficult to diagnose

- tender in syndesmosis & interosseous membrane

- positive squeeze test

 

Management

- arthroscopy and debride

- most will get better

 

3.  Meniscoid Lesion

 

Definition

 

Scar tissue beginning in the lateral gutter

- extending across between tibia and talus

- looks like a meniscus

 

Management

- arthroscopy and debride

- most get better

 

Bony Injury

 

1.  Fracture Anterior process of calcaneum

 

Pathology

 

Avulsion of the origin of the bifurcate ligament

- often missed if x-ray is in the wrong plane

 

Calcaneum Anterior Process Fracture

 

Diagnosis

 

Suspect if tender over anterior calcaneus

- CT or more plain films

 

Calcaneum Anterior Process Non Union

 

Management

- non-op for 6/12 

- most will unite or get a painless fibrous nonunion

 

2.  Fracture Lateral Process

 

Pathology

 

Eversion injury leading to lateral ankle pain

- tends to be larger than appears on plain x-ray

- often cause stiffness as involves STJ

 

Diagnosis

 

CT / MRI

 

Management

 

ORIF 

- > 1cm

- displaced > 2mm

 

Small and comminuted 

- excise

 

3.  Fracture Sustenaculum Tali

 

Caused by impaction on medial malleolus as the talus internally rotates

 

Management

- usually treat non-operatively

 

4.  Fractured Os peroneum 

 

Pain distally over the CCJ

 

Management

- non-operative initially

- late excise 

 

5.  Bone bruise

 

Pathology

 

Oedema in bone usually medial talar body and medial malleolus

- initial injury settles 

- get pain with resumption of activity

 

Diagnosis

 

MRI 

 

Management

 

Usually settles in 6/12

 

5.  Osteochondral fracture

 

Mechanism

- occur as the talus is inverted within the mortise

 

Pathology

 

Anterolateral 

- caused by shear stresses as the lateral talus abuts the lateral malleolus 

- tend to be smaller and generally do better

 

Posteromedial 

- caused with medial ridge impacting the roof

- more significant injury

- tends to be larger with underlying necrotic bone

 

6.  Loose Body

 

Tendon / Ligament

 

1.  Deltoid Tear

 

Pathology

- severe injury / almost an ankle dislocation

- gross inversion of talus with distraction 

- complete tear of lateral structures and tear of deltoid

- medial pain with lateral sprain

 

Management

 

Initially treat non-operatively

- may need debridement / repair

 

2.  High Ankle Sprain

 

Pathology

 

Injury to AITFL

- point tenderness and swelling

 

Management

 

Exclude diastasis

 

Treat non-operatively

- will take 12 weeks

 

Can benefit from late debridement

 

3.  Peroneal Dislocation

 

Pathology

 

Occurs with inversion while plantar flexed (strong contraction of peroneals)

- more common in cavus type feet 

- usually not diagnosed at the time

 

Symptoms

 

Patient complaining of painful snapping or clicking on lateral ankle

- after ~ 1/12 get synovial lined pouch anterior to malleolus from chronic subluxation

- won't heal

 

Management

 

Operative

- surgery with repair &/or deepening of groove

- repair and augment with periosteal flap or slip of Tendo achilles

 

4.  Peroneal Tear

 

Single or multiple longitudinal split

- associate with subluxation / dislocation

- associated with cavus feet

 

5.  Sinus Tarsi Syndrome

 

Lateral ankle pain

- injury to interosseous ligament

- residual synovitis

 

Management

- HCLA

- excision of contents of sinus

 

6.  Achilles tendonitis

 

Insertional tendonitis

Retrocalcaneal bursitis

Haglund' s deformity