Effect of Peroneus Longus Muscle Release on Abductor Hallucis Muscle Activity and Medial Longitudinal Arch before Toe-Tap Exercise in Participants with Flexible Pes Planus

Pes planus is a medical condition of the foot wherein there is a flattening or lowering of the medial longitudinal arch. The abductor hallucis muscle starts at the heel bone and attaches to the medial side of the first toe. Whenever it contracts, it plays a key role in elevating the medial longitudinal arch. Hence, the abductor hallucis muscle should be strong enough to control the depression on the medial longitudinal arch. The peroneus longus muscle plantarflexes the ankle and everts the ankle and subtalar joint. If this muscle contracts more than the abductor hallucis muscle does, the medial longitudinal arch of the foot is depressed. This study aimed to investigate the effect of myofascial release of the peroneus longus before performing the toe-tap exercise for strengthening the abductor hallucis muscle in participants with flexible pes planus. This cross-over study included 16 volunteers with flexible pes planus. The participants performed a toe-tap exercise before and after the myofascial release of the peroneus longus. During the toe-tap exercise, the muscle activity of the abductor hallucis and peroneus longus were measured using a Delsys Trigno Wireless Electromyography System. The angle of the medial longitudinal arch was measured using Image J software. Photos in the sagittal plane were used. The peroneus longus activity and medial longitudinal arch angles were significantly decreased. On the other hand, the activity of the abductor hallucis significantly increased after the myofascial release of the peroneus longus before performing the toe-tap exercise (p < 0.05). Individuals with flexible pes planus should be encouraged to perform myofascial release of the peroneus longus before the toe-tap exercise to improve the abductor hallucis activity and to elevate the medial longitudinal arch.

“Like For Like” Reconstruction of Heel Pad with Medial Plantar Artery Flap—Functional and Aesthetic Outcomes in A Series of 19 Cases

Heel pad loss can cause serious problems in weight-bearing and locomotion. The medial plantar artery (MPA) flap is a suitable “like for like” replacement. Nineteen patients whose heels were reconstructed with MPA flap between July 2015 and February 2020 were studied. All patients were assessed based on flap survival, functionality, and patient satisfaction. Loss of heel pad was due to diabetic ulcer (11), trauma (6), tumor (1), and unstable scar (1). The largest flap measured 9 × 7 cm. Sixteen flaps were done as fasciocutaneous flaps and three in combination with abductor hallucis muscle (AbdH). All the flaps survived. The average functional scores at 6, 12, 18, and 24 months were 86.86, 89.62, 89.38 and 97.33 based on AOSAS-AH score. Average patients' satisfaction was 8.7/10. To conclude, the MPA system is a versatile vascular axis providing “like for like” tissue for heel pad reconstruction which is reliable and durable.

Ultrasound Comparison of the Abductor Hallucis Muscle Between Normal and Hallux Valgus Feet After Long-Distance Running: A Pilot Study

Purpose: Previous research has indicated that the structure and function of abductor hallucis muscle (AbdH) would be adversely affected by hallux valgus (HV). However, the influence of long-distance running on AbdH in HV feet has not been explored. Therefore, this pilot study aimed to compare the imaging differences of AbdH between normal and HV feet after long-distance running. Methods: A total of 14 male adults were divided into two groups (Normal Foot Group (NFG), Hallux Valgus Group (HVG)) based on their foot morphology. A B-mode ultrasonic scanner was utilized for measuring AbdH thickness, cross-sectional area, and pennation angle before and after 5-km running test. Perceived soreness was monitored simultaneously using the visual analogue scale. Results: AbdH showed significantly differences between groups before and after the running test. Compared with NFG, HVG exhibited smaller value before the test while greater changes in all parameters although pennation angle failed to reach the significant level. Conclusions: These results further confirmed that HV could lead to the morphological alterations of AbdH. Also, AbdH of people with HV would endure more fatigue and soreness when performed the same long-distance running test with normal counterparts. Nevertheless, more studies are much needed for further verification.

First clinical experience of a new surgical technique including correction of bony alignment of first foot ray combined with reconstruction of muscle balance in case of adolescent hallux valgus

BACKGROUND: Hallux valgus deformity of the big toe in adolescents accounts for 22%44% of all relevant cases. Despite a relatively large number of surgical treatment methods proposed to correct this deformity, treatment results are not always satisfactory. The problem of imbalance between the external traction of the abductor hallucis muscle and the contracted adductor muscle in hallux valgus remains controversial and is not covered in the literature. AIM: This study aimed to examine the results of hallux valgus deformity treatment, following the suggested combined technique. MATERIALS AND METHODS: Eight teenage patients (10 feet), aged 15 years on average, were assessed. Patients were undergoing treatment in the department of pediatric orthopedics of the Dana Hospital, Tel Aviv, within the period from 2015 to 2019. The average postoperative observation period was 30 months. This study suggested a new combined technique, including (1) modified oblique Chevron osteotomy with a V-shaped cut in the distal aspect of the first metatarsal with the dorsal wedge excision performed at the apex of its angulation, (2) valgus osteotomy of the medial cuneiform bone with the insertion of the V-shaped bone allograft, and (3) transfer of the dorsal portion of the pre-split tendon of abductor hallucis muscle to the base of the triangular medial capsular flap of the first metatarsophalangeal joint (MPJ). The tendon received optimal tension to restore the muscular balance. RESULTS: This surgical technique provided safe and stable correction of the hallux valgus deformity, restored muscular balance, avoided movement restriction of the first MPJ, and restored the function and strength of the abductor halluces muscle that prevented the recurrence of the deformity. The number of good and excellent results was much greater than those in published reports. CONCLUSIONS: Despite a relatively small group of patients, the suggested technique has shown improvements in hallux valgus deformity in adolescents.

Muscle Activity Detectors—Surface Electromyography in the Evaluation of Abductor Hallucis Muscle

Despite the high availability of surface electromyography (sEMG), it is not widely used for testing the effectiveness of exercises that activate intrinsic muscles of foot in people with hallux valgus. The aim of this study was to assess the effect of the toe-spread-out (TSO) exercise on the outcomes of sEMG recorded from the abductor hallucis muscle (AbdH). An additional objective was the assessment of nerve conduction in electroneurography. The study involved 21 patients with a diagnosed hallux valgus (research group A) and 20 people without the deformation (research group B) who performed a TSO exercise and were examined twice: before and after therapy. The statistical analysis showed significant differences in the third, most important phase of TSO. After the exercises, the frequency of motor units recruitment increased in both groups. There were no significant differences in electroneurography outcomes between the two examinations in both research groups. The TSO exercise helps in the better activation of the AbdH muscle and contributes to the recruitment of a larger number of motor units of this muscle. The TSO exercises did not cause changes in nerve conduction. The sEMG and ENG are good methods for assessing this exercise but a comprehensive assessment should include other tests as well.

An Anatomical Basis for the Myofascial Trigger Points of the Abductor Hallucis Muscle

Myofascial pain syndrome is characterized by pain and a limited range of joint motion caused by muscle contracture related to motor-end-plate dysfunction and the presence of myofascial trigger points (MTrPs). It is the most frequent cause of musculoskeletal pain, with a worldwide prevalence varying between 13.7% and 47%. Of the patients with myofascial pain syndrome, approximately 17% have pain in the medial hindfoot area. The abductor hallucis muscle is located in the medial, posterior region of the foot and is related to painful plantar syndromes. The objective of this study was to describe the distribution of the medial plantar nerve and their anatomical relationship with MTrPs found in the literature. Thirty abductor hallucis muscles were dissected from 15 human cadavers (8 males and 7 females). The muscles were measured, and the distribution data of the medial plantar nerve branches in each quadrant were recorded. For statistical analysis, we used generalized estimation equations with a Poisson distribution and a log logarithm function followed by Bonferroni multiple comparisons of the means. The data are expressed as the mean ± standard deviation. The level of significance was adjusted to 5% (p<0.05). A high concentration of nerve branches was observed in the first quadrant (Q1) of the abductor hallucis muscle, which is the same area in which the MTrPs are described. The topography of the entry points of the branches of the medial plantar nerve to the abductor hallucis muscle correlates with the topography of the muscular trigger points. The anatomical structure of the MTrPs may be useful for a better understanding of the pathophysiology of myofascial disorders and provide a basis for surgical and clinical treatments.