How To Diagnose Lateral Ankle Injuries

Author(s): 
By Remy Ardizzone, DPM, and Ronald L. Valmassy, DPM

   However, there are some cases in which inverting the foot may exacerbate some cases of lateral ankle instability. In these cases, it is appropriate to pronate the foot maximally during the casting procedure and introduce an iatrogenic forefoot valgus deformity. One may then instruct the orthotics laboratory to correct the valgus deformity with the patient stabilized in this pronated position. Clinicians should then consider the presence of a limb length inequality as contributing to lateral ankle instability. A shortened limb may often function in a more supinated or inverted fashion in an attempt to equalize leg length. In these cases, employing a heel lift with or without a functional foot orthosis may prove successful in increasing stability.52,53

A Guide To Differential Diagnosis Of Lateral Ankle Injuries

   Lateral collateral ligament sprain
   Syndesmosis sprain (high ankle sprain)
   Lateral malleolar fracture
   Lateral talar process fracture
   Anterior process calcaneus fracture
   Subtalar injury
   Fifth metatarsal base fracture
   Peroneal tendon injury
   Osteochondral injury
   Peroneal nerve injury
   Sural nerve injury
   Calcaneocuboid injury
   Intraarticular loose body/impingement

Key Contributing Factors To Inversion Ankle Injuries

   Ligamentous laxity
   Ankle varus
   Tibial varum
   Forefoot valgus
   Uncompensated equinus
   Rigid plantarflexed first ray
   Peroneal muscle weakness
   Limb length discrepancy
   Supinated subtalar joint
   Prior inversion ankle injury

In Conclusion

   Many different lateral ankle injuries may have similar presentations and more subtle injuries may be overshadowed by the initial acute trauma. Ensuring a thorough understanding of the acute and functional aspects of lateral ankle injuries will allow practitioners to provide effective and efficient care for patients presenting with these injuries.

Dr. Ardizzone is a Staff Podiatrist at the Center for Sports Medicine at St. Francis Memorial Hospital in San Francisco, Calif. She is an Associate of the American College of Foot and Ankle Surgeons.

Dr. Valmassy is a Staff Podiatrist at the Center for Sports Medicine at St. Francis Memorial Hospital in San Francisco, Calif. He is a Fellow of the American College of Foot and Ankle Orthopedics and Medicine. Dr. Valmassy is also a Diplomate of the American Board of Podiatric Orthopedics and Primary Podiatric Medicine.

For related articles, see “How To Manage Lateral Ankle Sprains In Athletes” in the November 2003 issue or “Revisiting A Proven Approach To Severe Ankle Instability” in the November 2004 issue of Podiatry Today. Also be sure to visit the archives at www.podiatrytoday.com.




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