Chronic ankle instability

1. Chronic Ankle Instability
Presented by: Dr Bushu Harna
MBBS, MS Ortho (MAMC), Dip
SICOT

2. • Chronic lateral ankle instability (CLAI) is defined as recurrent sprains or repeated
“giving way” resulting from trauma for at least 1 year.
• Giving way is considered an uncontrolled or unpredictable excessive inversion of
the ankle joints that occurs at heel strike or toe-off during walking or running.
• It is estimated that 80 to 85% of ankle sprains occur to the lateral ligaments an
inversion ankle
• Only risk factor is previous ankle sprain
• Lateral ankle ligaments and bone congruency are main static stabilizers.
• Peroneal tendons provide dynamic stability.
• ATFL is most common injured ligament

4. LATERAL LIGAMENTS INJURY
• Inversion type of sprains
• Happens due to unstable landing after a jump or running/walking on an uneven
surface. It results from the inversion and plantarflexion of the foot injuring the
ATFL.
• A lot of force applied to the ATFL during the inversion sprain may break it and
affect the CFL. The effect occurs because the CFL is the next ligament supposed to
take the stress.
• The CFL can be injured if the inversion sprain is extreme enough.

5. • Anterior Talofibular Ligament
• ATFL primarily resists translational laxity of the talus in the sagittal plane.
• ATFL has the lowest threshold for failure and thus is the most commonly injured
ligament.
• Calcaneofibular Ligament
• CFL resists excessive supination at both the mortise and the subtalar joint.
• Posterior Talofibular Ligament
• PTFL is a robust ligament with a broad surface conferring a high tensile strength.
• Provides resistance to inversion and internal rotation.
• Injury to the PTFL is the least likely to occur.

6. Pathogenesis
• Usually the sequelae of an acute sprain that fails to heal properly.
• Ligaments may remain torn.
• Most commonly, heal but in an elongated fashion.
• Can result from loss of proprioception, muscle weakness, nerve injury, or tendon
damage.
Two main types of instability can be distinguished:
• Mechanical instability related to anatomic abnormalities of the ankle, usually related
to ligament laxity.
• Functional instability related to posture defects or tendon and muscle adjustment,
usually related to a proprioceptive deficit.

7. Mechanical instability
• Bone instability: a congruence defect as well as a more anterior position of the
talus in relation to the tibia on the loading.
• The lateral malleolus seems to be in a posterior position because of distension or
rupture of the anterior talofibular ligament.
Functional Instability
• Can result from alteration in proprioception, neuromuscular control, postural
control and the resultant strength deficits after sustaining an ankle sprain.
• The end result is a propensity for recurrent ankle sprains, persistent pain, and
muscular weakness.

10. Presentation
• history of injuries
• occurrence of repeated episodes of lateral ankle instability
• pain
• swelling
• ‘‘giving way”
• loss of motion

11. Physical Exam
• Lateral sided ankle tenderness
• Range of motion
• Provocative tests including anterior drawer (sulcus sign) and
• Talar tilt test
• Neuromuscular exam
• Assessment for hindfoot alignment, equinus contracture
• Weakness of peronei
• generalized signs of hypermobility
• Romberg test for proprioception

12. Other Lateral Injuries
• 5th metatarsal avulsion fracture
• Jones fracture
• Peroneus brevis tendon tear
• Peroneus longus tendinopathy
• Cuboid fracture

13. Anterior drawer test:
• The patient needs to be relaxed, seated with the knee flexed and
the ankle plantar flexed around 10-20 degrees.
• One of the examiner’s hands stabilises the tibia and, with the
other hand, the foot is pulled forwards.
• Stabilise the heel on the bed with one hand and push tibia with
the other hand.
• The test should be compared with the contralateral ankle.
• A sulcus sign is present when a dimple is seen in the lateral
gutter on testing.

14. Talar tilt test: Can evaluates both ATFL and CFL.
• With the ankle plantigrade the hindfoot is tilted one way.
• Pain or gap at palpation.

15. Imaging Studies
• Plain standing films--Alignment and bone injury
• Stress radiographs comparing the affected side to the
unaffected sign are the gold standard for mechanical
stability.
Stress Views
• A difference of >4mm in anterior drawer and >6 degrees on
talar tilt is significant for instability.
• >15 degrees of talar tilt or >1 cm anterior translation also
usually considered abnormal.

16. • Ultrasound
• MRI: Allows not only the assessment of the ATFL and CFL but also of
local tendons and bones.

17. Treatment
• Non-operative treatment is the first line of therapy.
• Strength training and proprioception instruction are used, focusing on taking the ankle
through a full range of normal motion.
• Bracing may help protect from reinjury but does not correct underlying pathology.
• Taping/ lateral heal wedges
• Peroneal strengthening

18. Surgical Treatment
• Indicated if instability symptoms persist after 3-5 months of rehab attempts.
• FI with no MI = no surgery
• MI with no FI = no surgery
• MI with FI = proprioception, strength training. If no improvement then surgery

19. Two main types: anatomic repair or non anatomic/ tenodesis stabilization
• Anatomic repair restores normal anatomy and biomechanics while
maintaining ankle motion
• Tenodesis stabilization restricts laxity and pathologic motion but ignores
the underlying ligamentous pathology. Stabilization is achieved at the
expense of altering normal ankle and hindfoot biomechanics.

20. Anatomic Ligament repair
• Anatomical repair gives the best results and is indicated in most patients. Anatomical
repair of the existing ATFL and CFL to bone was described by Brostrom but the
modification by Gould is currently most popular. Gould recommended reinforcement
of the repair using inferior extensor retinaculum.
• Anatomical repair is not only simple, it also restores ankle kinematics to near normal
compared to ligament reconstruction techniques.
• Arthroscopic Brostrom-Gould repair.

21. Ligament reconstruction: Can be performed using a number of options: native
autografts, allografts or synthetic implants.
• May be a role for early ligament reconstruction in patients with a high BMI, heavy
manual jobs, sportsmen or those with generalised ligament laxity who may
overstress the repaired ligament and are therefore at high risk of failure of primary
repair.
• Reconstruction is also indicated when there is insufficient native ligament left for
adequate repair.
• Arthroscopic assessment reveals the ATFL to be highly irregular in appearance.

22. Non-anatomic lateral ligament reconstruction: A number of procedures have been
described.
• Watson Jones described re-routing of the peroneus brevis (PB) tendon between the
talus and the calcaneus.
• This was subsequently modified by Evans, who preferred re-routing via the distal
fibula.
• Chrisman and Snook detached only a portion of PB, keeping its distal attachment
intact.
• The main criticism: Restrict the movement of the subtalar joint and also sacrifice the
PB tendon, which is an important lateral stabiliser of the ankle.

24. Recommendations
1.Surgery is suggested when patients continue to have symptoms of CLAI after 3 to 6
months of nonsurgical treatment and have indications of CLAI on physical and
imaging examinations (stress radiography or MRI).
2.Simultaneous surgery for CLAI and OCL lesions of the talus or tibia is suggested
when both are present.
3.Open and arthroscopic procedures are both recommended in patients with CLAI
who undergo anatomic repair or reconstruction.
4.Autograft and allograft are both recommended for anatomic reconstruction in
patients with CLAI.
5.When patients with CLAI have subtalar joint instability and both the ATFL and the
CFL are ruptured, ATFL and CFL reconstruction is suggested.

25. 6. For patients with CLAI who undergo anatomic repair or reconstruction, ROM
(mostly dorsiflexion) and partial weightbearing with a brace from the second day after
surgery are recommended; for those with OCL who undergo anatomic repair or
reconstruction and additional microfracture, early ROM and relatively delayed
weightbearing are recommended.
7. Joint stability, muscle strength, and full ROM are recommended prior to returning to
sport after surgery.

26. Thank You for Patient Listening