Choosing among 3 ankle-foot orthoses for a patient with stage ii posterior tibial tendon dysfunction

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C ASE R EPORT

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CHRISTOPHER NEVILLE, PT, PhD¹

PT, PhD²

Choosing Among 3 Ankle-Foot Orthoses for a Patient With Stage II
Posterior Tibial Tendon Dysfunction

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osterior tibial tendon dysfunction (PTTD) is typically described as a progressive disorder ranging from stage I to stage IV, with hallmarks of advancing flatfoot deformity and deteriorating function. Ultimately, stage IV is identified by the presence of arthritic changes in the lateral talocrural joint.25 The timeline for progression of this dysfunction is not clear, though strengthening programs and the use of orthoses may slow its progression.24,26
Case report.
No head-to-head comparisons of different orthoses for patients with stage II posterior tibial tendon dysfunction (PTTD) have been performed to date. Additionally, the cost of orthoses varies considerably, thus choosing an effective orthosis that is affordable to the patient is largely a trial-and-error process.
A 77-year-old woman was seen with complaints of abnormal foot posture (“my foot is out”), minimal medial foot and ankle pain, and a 3-year history of conservatively managed stage II PTTD. The patient was not able to complete 1 single-limb heel rise on the involved side, while she could complete 3 on the uninvolved side. Ankle strength testing revealed a mild to moderate loss of plantar flexor strength
(20%-31% deficit on the involved side), combined with a 22% deficit in isometric ankle inversion and forefoot adduction strength. To assist this patient in managing her flatfoot posture and PTTD, 3 orthoses were considered: an off-the-shelf ankle-foot orthosis (AFO), a custom solid AFO, and a custom articulated AFO. The patient’s chief complaint was partly cosmetic (“my foot is out”). As decreasing flatfoot kinematics may unload the tibialis posterior muscle, thus prevent the progression of foot deformity, the primary goal of orthotic intervention

was to improve flatfoot kinematics. Given the