Lateral Ankle Pain

1. Lateral Ankle Pain Dr Riaan Barnard MBChB, BSc Hons M Sport Med (3’rd year)

2. Case History • Mr V presented 3 weeks ago with chronic L sided lateral ankle pain • Pain history of about 8/12 • Would wake up with severe ankle pain in the morning – improve during day • Works for Telkom, has to climb ladders against telephone poles daily, out in rural areas daily, walking a lot on uneven ground, sometimes mountain areas • Sometimes pain radiating rear foot area, feeling of instability when walking uneven surfaces • Previous history of MVA – Grade II ATF injury with severe inversion mechanism. This was fully rehabilitated, Matador Lace-up brace used • No other medical history of note

3. Clinical Examination • Pain +/- 2cm maximally anterior to L lateral maleolus; dull and poorly localised • No swelling, redness, no pain at N-point • No mechanical instability of hind – mid foot • Pain and mild stiffness with passive inversion • On pressure to the sinus tarsi, dull aching pain deep in ankle followed Diff Diagnoses • Sinus Tarsi and Canalis Tarsi Syndrome • Antero-lateral Impingement Syndrome • Chronic Gout • Stress Fracture Talus

4. Special Investigations • Sonar in rooms - ? Fibroses and ATF thickening • X-rays – no bony pathology • Uric acid levels, ESR & CRP all normal • 1 ml of 1% Lignocaine injected sonar-guided into sinus tarsi. Waited for 10 minutes, Mr V asked to walk some distance and ankle re-examined. On return examination, 100% resolution of pain.

5. Bio-Psycho-Social

6. Treatment Plan & Progression • Sonar guided infiltration of Sinus Tarsi and Canalis Tarsi with 2cc Celestone Soluspan, mixed with 1cc Naropin • Referral to Physiotherapist for • Mobilisation subtalar joint • Proprioception exercises • Strengthening lateral ankle muscles Mr V has not returned yet for follow up after the above interventions.

8. Discussion Anatomy • Small osseous canal with opening antero-inferior of lateral maleolus; ascending cranially by 10°, directed dorsally by 45° to point posteromedial direction to open posterior of medial maleolus • Interosseous ligament lies inside Canalis Tarsi, dividing it in anterior portion – part of the TCN joint – and posterior portion – as part of the subtalar joint. • Sinus Tarsi at its opening has a fat pad covering it, rich in blood vessels, fat and connective tissue, with the canal lined out by synovial membrane

9. Cruciform arrangement of strong Talo-Calcaneal Interosseous Ligament (TCIL), expanding from lateral to medial between calcaneus and talus, anchoring the two bones strongly together • TCIL extends exactly in the axis of movement of the subtalar joint, which is important with regard to hindfoot stability and mobility in relation to inversion and eversion movements

10. Ant TFL 3 Layers Ext Brevis Retinaculum ATF Lat TCL Post Facet Calcaneus CFL Fibula Peroneal Tendons

11. Causes Sinus Tarsi Syndrome • 70% of all patients had single / repeated inversion injury of ankle • Repeated, forced eversion to ankle during high jump take off • Chronic overuse injury due to poor biomechanics, especially excessive subtalar pronation • Gout, inflammatory arthropathies and osteoarthritis

12. Clinical Manifestations O’Connor & Brown in 1957 described the first of 2 syndromes, the STS being the first. The Canalis Tarsi Syndrome was later described as single entity, or occurring in conjunction with STS • Poorly localised pain, most often centered 1,5-2cm anterior to lateral maleolus in STS • Minor localized swelling and occasionally pain over ATF • Pain most severe in morning, diminishes with exercise, increases with running on curve in direction of painful ankle • Feeling of instability hind foot, difficulty in walking on uneven surfaces • Stiff subtalar joint, painful forced passive eversion and forced passive inversion • Canalis Tarsi Syndrome pain radiates from sinus tarsi opening across ankle to medial aspect of hind foot

13. Diagnoses • X-rays: to exclude any bony pathology / arthropathy • Sonar: acc to Shields et al (2003) abnormal hypoechogenicity within the sinus tarsi is compatible with STS. Identification of ATF ligament injury should prompt evaluation of the sinus tarsi, as both occur with inversion injuries • MRI: can show increased signal and fluid in the sinus tarsii • Arthrogram: acc to Zwipp et al (1996), shows sac-like bulge of the ventral synovial membrane of the subtalar joint. This line is normally finely denticulated

14. “Diagnostic Treatment” Zwipp et al (1996) suggested a single, sonar-guided 1cc 1% Lignocaine injection into the sinus tarsi as first part of clinical investigation. If the pain disappears suddenly, and pain-free functional hopping can be done afterwards, conservative treatment is indicated • 3-4cc of 2% Lignocaine + 1cc corticosteroid (Triamcinolone) can than be injected sonar-guided into the sinus tarsi via thin needle • Injections are to be repeated weekly or fortnightly for maximum 6 injections • 80% permanent success rates were achieved • Conservative treatment should always be fully exhausted before surgery should be considered

15. Injection Technique • Needle at the level of the lateral maleolus tip • Half a transverse finger ventrally to the turning margin of the lateral maleolus • Ascending cranially by 10° • Directed dorsally by 45° • Injections should be performed under sterile conditions • Patients must be informed about the possible risk of corticosteroid therapy • With the combination of Canalis Tarsi Syndrome symptoms, a much longer needle is used, and with sonar-guiding infiltration deep into the tarsal canal should be attempted

17. Other Treatment Modalities • Relative rest, ICE, NSAIDs and electrotherapeutic modalities • Subtalar joint mobilisation techniques • Biomechanical correction of excessive subtalar pronation • Rehab with proprioception and strength training techniques to peroneals and lateral ankle stabilisers • Brown in 1960 described operative technique which consists of dissection of the tarsal sinus by antero-lateral Ollier approach. Fat pad is first resected, inflammatory changes in the TCIL removed by debridement, capsulectomy was then performed, followed by resection of synovia in area of posterior facet • Modern approach now is through Arthroscopy

19. Learning Experience and Take Home Message Victim vs. Culprit

21. References • Brukner, P; Khan, K. Clinical Sports Medicine. Third Edition, 2008. pg 640-641 • Lee, KB et al. Subtalar Arthroscopy for Sinus Tarsi Syndrome : Arthroscopic Findings and Clinical Outcomes of 33 Consecutive cases. The journal of Arthroscopic & Related Surgery, vol 24 (10) Oct 2008. pg 1130-1134 • Oloff, LM et al. Subtalar Joint Arthroscopy for Sinus Tarsi Syndrome: A Review of 29 Cases. Journal of Foot and Ankle Surgery, Dec 2000. pg 152-157 • Pisani, G et al. Sinus Tarsi Syndrome and Subtalar Joint Instability. Clinics in Podiatric Medicine and Surgery, vol 22 (1) Jan 2005. pg 63-77 • Shields, G et al. Sonography of Sinus Tarsi Syndrome. Ultrasound in Medicine and Biology, vol 29 (5S), 2003 • Zwipp, H et al. Sinus Tarsi and Canalis Tarsi Syndrome. A Post-Traumatic Entity. Journal of Foot and Ankle Surgery, vol 2 1996. pg 181-188