Foot & Ankle

Ankle impingement is defined as a painful mechanical limitation of full ankle range of motion secondary to an osseous or soft-tissue abnormality.

 

The leading cause of impingement lesion is post-traumatic synovial hypertrophy, however, other causes include infection, inflammatory arthritis and degenerative disease.

 

It is characterised by chronic pain and limited range of movements. No formal classification exists but it is generally described according to the anatomical locations around the tibiotalar joint as anterior, anterolateral, anteromedial, posterior or posteromedial. For the sake of simplicity it can be described broadly as anterior (during dorsiflexion) and posterior (during plantarflexion, also known as talar compression syndrome) impingement.

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Pathophysiology

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Waller described a pain syndrome along the anteroinferior border of the fibula and anterolateral talus following repetitive inversion injuries and believed this pathology to be synovial compression or chondromalacia of the lateral talar dome.

 

Bassett et al. described that following a tear of the ATFL, the anterolateral talar dome extrudes anteriorly with dorsiflexion, resulting in impingement. Hamilton described a labrum or pseudomeniscus of the posterior lip of the tibia, which could become torn or hypertrophied with recurrent ankle sprains leading to posterior impingement.

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The anterior tibiotalar exostoses has been found to be intra-articular and well within the distal tibial and dorsal talar capsular attachments. Some studies describe them as “kissing osteophytes”, however preoperative CT scans have shown that talar spurs generally lie medial to the midline of the talar dome and tibial spurs are generally located laterally.

 

A triangular soft tissue mass composed primarily of adipose and synovial tissues may contribute to impingement in isolation or in conjunction with bony lesions. Chronic lateral instability, post-traumatic fibrous bands, thickened anterior tibiofibular ligaments and synovial plica may also cause impingement. Anterior ankle pain usually gets worse during activities of climbing stairs, walking uphill and deep squatting.

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Posterior impingement is most commonly caused by lateral process of the posterior talus (acute fracture or chronic repetitive injury). Other causes include osteophytes, reactive hypertrophy of capsule or synovium and malunited fractures of posterior malleolus, talus or calcaneum. Posterior ankle pain may be confused with Achilles tendon pathology. It usually gets worse during activities of descending stairs, downhill walking and wearing high-heel shoes. It classically presents in ballet-dancers.

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Diagnosis

 

Although the diagnosis is mainly clinical, however, MRI scan is the imaging of choice to demonstrate pathological soft tissue changes, bone marrow oedema and osteochondral lesions. Dynamic ultrasonography can be helpful to identify the anatomical structures causing impingement in a specific anatomic area.

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Treatment

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Conservative treatment

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First line of treatment for both types of impingement is non-surgical, however, the evidence is limited. In acute phase avoidance of triggering activities, limited period of rest, ice-packing, NSAIDs and splintage are recommended.

 

In chronic cases, shoe modifications and physiotherapy may improve symptoms. Some authors have reported symptomatic improvement with ultrasound-guided steroid injections,

 

Surgical treatment

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Surgery is indicated for persistent symptoms which do not respond to non-operative treatment, interfere with activities of daily-living or athletic performance. The targeted surgical approach and technique is guided by the location of symptoms.

 

The treatment of choice for anterior impingement is arthroscopic debridement of bony and soft tissue structures according to the pathology involved. Intra-operative fluoroscopy may be required to confirm adequate excision of the bony spur.

 

In a systematic review, Zwiers et al. reviewed 19 studies with a total of 905 patients (average age 32.7 years, combined mean follow-up 35.3 months) and showed that 74–100% patients were satisfied with the results of their procedure. AOFAS scores improved consistently, ranging from 34–75 preoperatively and increasing to 83.5–92 postoperatively. There was a 5.1% overall complication rate, with 1.2% considered as major complications.

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For posterior impingement, the preferred approach is arthroscopic, however, an open lateral or an open medial approach may be required depending on the pathology and location. Zwiers et al. in another systematic review, included 16 studies and showed significantly lower complication rates (7.2% vs. 15.9 %) and earlier return to full activity (11.3 vs. 16 weeks) were found with arthroscopic surgery compared to an open approach.

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Brennan et al., presented the results of 41 cases of arthroscopic debridement for soft tissue impingement and showed a significant improvement in mean visual analogue scale foot and ankle (VASFA) scores with good to excellent results in 83% cases.

 

Parma et al. investigated the long-term outcomes of 80 consecutive patients who underwent arthroscopic debridement of bony impingement. The authors evaluated AOFAS scores preoperatively, at 24 months, and a mean final follow-up of 104.6 months. On average, AOFAS scores improved significantly, however, 40% patients reported AOFAS scores below 70 at their final follow-up.

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Calder et al. published a series of 23 elite soccer players treated arthroscopically for posterior impingement and showed that 11 athletes returned to full level of sports in an average duration of 41 days (range 29 to 72 days). The return to function and training was quicker in those players treated for soft tissue impingement lesions rather than bony impingement lesions.

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Summary

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Ankle impingement is a common condition after a previous injury.

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Initial treatment is conservative with pain management and activity modification until it fails.

 

Surgical treatment of choice is arthroscopic assessment and debridement with satisfactory results. 

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References

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• Umans HR, Cerezal L. Anterior ankle impingement syndromes. Semin Musculoskelet Radiol. 2008 Jun. 12(2):146-53.

• Waller JF. Hindfoot and midfoot problems. Symposium on the foot and leg. Mack RP, ed. Running Sports. St. Louis, Mo: Mosby; 1982. pp 64-71.

• Bassett FH 3rd, Gates HS 3rd, Billys JB, Morris HB, Nikolaou PK. Talar impingement by the anteroinferior tibiofibular ligament. A cause of chronic pain in the ankle after inversion sprain. J Bone Joint Surg Am. 1990 Jan. 72(1):55-9.

• Hamilton WG. Tendonitis about the ankle joint in classical ballet dancers. Am J Sports Med. 1977 Mar-Apr. 5(2):84-8.

• Lavery et al. Journal of Orthopaedic Surgery and Research (2016) 11:97; DOI 10.1186/s13018-016-0430-x

• Zwiers R, et al. Arthroscopic treatment for anterior ankle impingement: a systematic review of the current literature. Arthroscopy. 2015;31(8):1585–96.

• Zwiers R, et al. Surgical treatment for posterior ankle impingement. Arthroscopy. 2013;29(7):1263–70.

• Brennan SA, Rahim F, Dowling J, Kearns SR. Arthroscopic debridement for soft tissue ankle impingement. Ir J Med Sci 2012;181(2):253–6.

• Parma A, Buda R, Vannini F, Ruffilli A, Cavallo M, Ferruzzi A, et al. Arthroscopic treatment of ankle anterior bony impingement: the long-term clinical outcome. Foot Ankle Int 2014;35(2):148–55.

• Calder JD, Sexton SA, Pearce CJ. Return to training and playing after posterior ankle arthroscopy for posterior impingement in elite professional soccer. Am J Sports Med 2010;38:120–4.