Chronic Ankle Instability

Gregory Alvine MD

Core Orthopedics

Avera Medical Group

Outline

• Epidemiology

• Anatomy/Biomechanics

• Acute Lateral Ankle Instability

• Chronic Lateral Ankle Instability

**Thanks to Dr. Sherman & Bohon for some of the content of this talk

Epidemiology

• > 28,000 ankle sprains per day in the US • Kaminski et al, J Athl Train 2013

• Appx 55% of people with ankle sprains do not seek medical treatment, so the incidence is even higher than reported

• Biggest risk factor: previous ankle sprain

Incidence

• Lateral ankle sprains/inversion type injury

– 73-85% of all ankle injuries • Maffulli et al, JAAOS 2008

• “High” ankle sprains/syndesmotic injury

– 1-18% of all ankle sprains

Lateral Ankle Ligamentous Complex

• Comprised of:

– ATFL – Anterior Talofibular Ligament

– CFL – Calcaneofibular Ligament

– PTFL – Posterior Talofibular Ligament

Lateral Ankle Ligament Biomechanics

• ATFL is weakest ligament – CFL is 2-3x stronger – Neutral or Dorsiflexion

• Ankle Inherently Stable – Wider Anterior Talus – CFL controls varus tilt – ATFL control anterior

– Plantarflexion • Ankle Inherently Unstable

– Smaller posterior talus – ATLF resists varus tilt

Syndesmosis Complex

• Comprised of: – AITFL: Anterior Inferior Tibiofibular Ligament (35%)

– PITLF: Posterior Inferior Tibiofibular Ligament (22%)

– IOL/IOM: Interosseous Ligament/Membrane (42%)

Acute Lateral Ankle Instability

Mechanism of Injury

• Inversion of a plantarflexed ankle

– Excessive inversion and IR of hindfoot, with relative ER of the leg

– Sequential Injury:

• ATFL (85%)

• CFL (20-75%)

• PTFL (<10%)

– Disruption of capsular mechanoreceptors

• Impaired balance/proprioception

History and Physical Examination

•History –“Rolled ankle”, “Heard pop” –Mechanism of Injury:

inversion in plantarflexion –Severity : Able/unable to play or WB –Chronicity: First event vs. recurrent

• Physical Exam –Standard Foot/Ankle Exam –Swelling/ecchymosis to localize pathology –Tenderness to Palpation “TTP” (ATFL, CFL) –Neurovascular Exam

•High Incidence of peroneal nerve injury w/ severe sprains – Neuropraxia: Sensory changes

Physical Exam: Stress Testing

–Anterior Drawer testing: • Amount of anterior displacement of the talus

from the ankle mortise in Neutral Position

• ATFL Laxity: compared to the contralateral side

–Inversion (Talar Tilt) testing:

• Amount of talar tilt noted

• Test Neutral/DF: CFL

• Test Plantarflexion: ATFL

• Laxity: compared to the contralateral side

Imaging Studies

• Standard Weight Bearing Ankle AP, Lateral, and Mortise Views

–Ottawa rules

– An ankle X-Ray series required if pain in malleolar zone and any of these findings: –Bone tenderness at A –Bone tenderness at B – Inability to bear weight both immediately and in the ED

–Rule out fracture and associated pathology

–Stress views (anterior drawer/talar tilt) controversial

MRI

•Routine use of MRI is not recommended for all acute ankle sprains

•Relative indications for MRI: –Acute high grade lateral ankle sprain in elite athlete when

contemplating early operative repair

–Chronic refractory ankle instability

–Suspicion of high grade syndesmotic injury in an athlete

Classification of Ankle Sprains

–Grade I: ATFL Stretched

• PE: +TTP ATFL, mild swelling, no ecchymosis, mild ROM loss,

+/‐ difficulty with weight bearing, no instability

–Grade II: Partially torn ligament

• PE: +TTP ATFL +/‐ CFL, moderate swelling, + ecchymosis, restricted ROM, mild or absent laxity

–Grade III: Complete Tear

• PE: +TTP ATFL/CFL, diffuse swelling, ecchymosis lateral and heel, inability to weight bear, ROM restriction > 10 degrees

• IIIA – Anterior Drawer Stress X‐ray (‐) • IIIB – Anterior Drawer Stress X‐ray (+)

Stable

Unstable

Ankle Sprains: Injury Prevention

•Ankle Sprain Prophylaxis: – Moderate evidence to support the use of prophylactic ankle braces in adolescent athletes, particularly those who participate in football and basketball, to reduce the incidence of acute ankle injuries.

Journal Sports Rehab 2013

–AJSM 2011 : Male and Female High School Basketball

• Lace‐up ankle braces reduced incidence but not severity of acute ankle injuries

–AJSM 2012 : RCT 2081 HS football players

• Lace‐up ankle braces had a lower incidence but not severity of acute ankle injuries

Ankle Sprains: Management • RICE + Protected Weight Bearing

– Cold Therapy: (Hocutt et al, AJSM 1982) • Ice Pack 15 min 3x/day

• Faster recovery with early cold therapy (initial 36 hrs) vs. delayed cold vs. heat therapy

• Grade I & II Injuries: – Functional Treatment:

• WBAT

• Early mobilization w/ brace/taping

• ROM, Strengthening program

• Proprioceptive training

– Eiff et al, AJSM 1994 • Prospective Study: Early Mobilization

vs. NWB Plaster Splint • Results:

– Excellent results for both methods

– At 10 days after injury EM group significantly more likely to return to full work

– 5% residual symptoms, 8% re‐injury

• Conclusion: EM > Immobilization

Ankle Sprains: Management

•Functional Management •Early Mobilization w/ functional brace •RICE (48hrs) WBAT •Strengthening, ROM •Proprioception training: recover balance and postural control, progressive drills (wobble boards/trampolines)

•Surgical Repair •Few indications for primary surgical management •Open Injuries, Large Avulsion Fx’s, Large OLT (osteochondral lesion of talus), Frank Dislocations

• Grade III injuries: •Cast Immobilization •Walking Cast/Boot x 3 weeks •Cast: 5 deg DF, Slight Eversion •Physical therapy program

Functional Management and RTP •Criteria for RTP: –Recovery of pain‐free ROM, strength, protective

reflexes

• Master sport‐specific drills with no discomfort

• Wear Ankle Brace or Taping when RTP until functional and anatomic stability achieved

–Acute Injury: If athlete can bear weight, perform jumping/running/cutting

• May return to play immediately

• If still unable to RTP –Consider more thorough evaluation/MRI

• r/o OCD of talus

• Peroneal tendon tear

• Occult fracture

• Missed syndesmotic injury

Ankle Sprains: Surgical Indications

•Majority treated non‐operatively – 75‐100% of patients have good outcomes regardless of nonsurgical/surgical

treatment

– Similar frequency of late symptoms:

• Instability, pain, swelling, stiffness

– Secondary Repair/Reconstruction = Acute Repair:

• Acute Repair vs. Delayed Reconstruction • (Kitaoka HB, J Orthop Trauma, 1997)

– 53 patients w/ 20 year follow‐up

• Results: – Acute Repair: Clinically G/E Outcome 21/22

– Delayed Reconstruction: Clinically G/E Outcome 27/31

– No significant difference in clinical outcomes – No significant difference in XR Stress Testing

– Surgical Indication: Chronic Instability

Chronic Ankle Instability

• Many factors contributing to chronic instability and ankle pain

• MRI often useful to help rule out other conditions – Peroneal tendinopathy, OCD or osteochondral lesions, lateral

or anterior process fracture, 5th metatarsal fracture, tarsal coalition, early DJD/synovitis

• Must consider alignment: Hindfoot varus – Common cause of failure

Stress X-Rays

• Talar Tilt

– > 5 deg difference between sides

– >15 deg tilt often implies rupture of ATFL and CFL

– Ant Drawer

• Abnormal anterior translation is between 5-10mm or 3 mm than other side

Treatment of Chronic Instability

•Conservative –Poorly tolerated

–Low demand • Co‐morbidities

• Bracing – AFO

– Double upright brace

•Primary indications for surgery: –Active Patient

–Recurrent instability

–Failure of Non‐surgical Management

–Painful associated pathology

Chronic Ankle Instability

• Treatment

– Conservative

• Correction of deficits in proprioception, strength, and flexibility

• Activity and shoe modification

• Orthotics (lateral heel wedge)

• AFO

Surgical Treatment

• Indications

– Failure of nonoperative plan

– Active patient

– X-Ray criteria helpful BUT symptoms and signs most critical

• Diagnostic Arthroscopy can be helpful if suspect intra-articular pathology

• Kibler – Arthroscopy – 46 consecutive

ankles prior to ligament repair

– 83% - intra-articular pathology • 26% Lateral ankle soft tissue

impingement

• 26% spurs (tibial or Talar)

• 15% meniscoid lesions

• 13% chondral injuries

• 13% loose bodies

• Other authors

– Chondral injuries ranging 25% - 66%

• Suggests: chronic unstable ankles should at least be evaluated for intra-articular problems

Surgical Options

• Direct Repair/Anatomic Repair

– Modified Brostrom/Gould

– Direct repair of the ATFL and CFL ligaments + inferior external retinaculum (IER)

Surgical Options (cont’d)

• Augmented reconstructions/non anatomic repair

– Typically with tendon graft (allograft vs autograft)

– Patients with severe laxity, weaker or deficient tissue

– Failed direct anatomic repair

Surgical Options

• Graft Options – Peroneal tendons, plantaris, fascia lata, achilles

tendon strip, hamstring tendon, allograft tendon

• Historically peroneal brevis tendon transferred through bone tunnels – Watson-Jones – Evans procedure – Larsen procedure – Chrisman-Snook – Elmslie

Surgical Options

• Direct vs augmented repairs have similar success rates

– Baumhauer et al

• Anatomic/Direct repairs – 85%-95% success

• Low risk

– Try to preserve subtalar joint motion in athletes

– Failed primary repairs typically resort to augmented constructions

Surgical Options

• Evaluate hindfoot alignment

– Calcaneal osteotomy necessary for significant varus

– Patients with weak peroneal function often require non-anatomic repair which limits subtalar motion

End Stage Arthritis

• 70%-80% ankle arthritis is post traumatic

– Beat Hintermann, et al

• Typically younger patients

– 13% related to ligamentous legion

• Lateral ankle ligament complex main cause – 85%

• Sports injuries – 55%

Ankle Arthritis

• Latency analysis

– Beat-Hintermann, et al

• Ankle sprain to end stage arthritis

– Single severe ankle sprain – 26 yrs

– Recurrent ankle sprain – 38 yrs

Ankle Arthritis

Chronic lateral ankle instability predominantly found to be correlated with varus-maligned ankle arthritis

Ankle Arthritis

• Treatment options

– Bracing (Arizona AFO or California Ritchie)

– Ankle Fusion

– Total Ankle Arthroplasty

Ankle Bracing

• Arizona AFO

• California Ritchie

Ankle Fusion

Tibial-Talo-Calcaneal Fusion

Total Ankle Arthroplasty

Chronic Ankle Instability

Thank You