A comparison of abductor hallucis muscle activation and medial longitudinal arch angle during nine different foot exercises.

BACKGROUND: Intrinsic foot muscles are known to support the medial longitudinal arch (MLA) and stabilize the foot, and they are activated with weight bearing and increased postural demand. Various types of intrinsic foot muscle training have been reported, but one of the most useful of these, the short foot exercise, is challenging to perform effectively and requires practice, making it difficult to implement in ordinary clinical settings. RESEARCH QUESTION: What are the differences in abductor hallucis longus (ABH) muscle activity and MLA angle during intrinsic foot muscle exercises that employ weight bearing and balancing conditions when they are performed with minimal practice? METHODS: Sixteen healthy volunteers performed nine different intrinsic foot muscle exercises, practiced once or twice. The exercises consisted of toe curl, short foot without pushing, short foot with pushing and toe spread exercises in sitting and standing positions, and single leg swing in a standing position. Each exercise was performed three times for five seconds. The activities of the ABH muscles were measured using surface electromyographic (EMG) sensors and the MLA angles during the exercises were captured using an optical motion tracking system. The integrals of the ABH EMG signals were calculated. RESULTS: Differences in the integral and maximum of the ABH EMG signal were found between the exercises (p < 0.001). Post-hoc pair-wise analysis revealed that the EMG activity was larger during the swing exercise than in exercises other than toe spread, both in sitting and standing positions, and short foot exercise with pushing while standing. The minimum MLA angle during each exercise was smaller for the toe spread exercise in a sitting position than other exercises (p < 0.023). SIGNIFICANCE: A single leg swing exercise may be effective for self-exercise of intrinsic foot muscles, particularly when intensive supervised physiotherapy is not possible.

Accessory muscles around the foot and ankle presenting as chronic undiagnosed pain. An illustrative case report and review of the literature.

The differential diagnosis of ankle pain is extensive. Pathology may be classified as intra- or extra-articular. Additionally, ankle pain may be traumatic or non-traumatic. One of the unusual differential diagnoses for pain in the ankle is an accessory muscle. Magnetic resonance imaging is the radiological investigation of choice. However, this is invariably reported as normal unless one specifically looks for an accessory muscle. The purpose of this report is to highlight important features of these muscles and to draw attention to this uncommonly reported condition.