Positional and dimensional relation of tendons around the first metatarsal bone with hallux valgus

Abstract

It was aimed to reveal whether the positions and dimensions of the extrinsic and intrinsic muscle tendons related to the hallux around the rst metatarsal bone are affected by the severity of hallux valgus (HV) and whether tendon positional changes and tendon sizes affect each other.In formalin-xed 46 feet, three HV angle subgroups (normal, mild and moderate/severe ) were de ned. Width, thickness and cross sectional area (CSA) of tendons of the extensor hallucis longus (EHL) and brevis (EHB), abductor hallucis (AH) and exor hallucis longus (FHL) were measured. On the clock model created in coronal plane, positional variations of each tendon were indicated. In the moderate-severe HV group, thickness and CSA of the EHB, width and CSA of the AH were smaller, compared to mild HV. Width and CSA of the FHL were smaller in moderate/severe HV than in the normal. Regardless of HV, the width and CSA of the FHL was greater in cases where the FHL located more lateral, and the width of both FHL and AT were greater in cases where AH located more plantar.The smaller tendon size of two intrinsic (one plantar and one dorsal) and one extrinsic muscle in the moderate/severe HV group indicates that the changes re ected in the tendons are more pronounced in the case of high HV severity, and the changes are not limited to the tendons on just one side of the foot. The possible biomechanical effects of AH, FHL and EHB tendon dimensional weakness may be important when planning surgery for moderate/severe HV cases.

The effect of hallux valgus on the anatomy of the nerves around the first metatarsal bone

“…The project is supported by Mersin University (PN:2021-1-TP2-4313) and approved by Clinical Research Ethics Committee of Mersin University (Approval number: 2021-96). (Our results for the rst part, in which the relationship of HV to the size and location of the tendons in the region were evaluated, have already been published [12]). The current study, which covers the second part of the project (performed on the same material), focused on identifying the localization of nerves that may be at risk of injury during surgeries around the FMB, and determining whether they are affected by HV.…”

“…The current study, which covers the second part of the project (performed on the same material), focused on identifying the localization of nerves that may be at risk of injury during surgeries around the FMB, and determining whether they are affected by HV. Hallux valgus angle (HVA) values and subgroups for hallux valgus level (i.e., normal, mild HV(HVA ≤ 20 ) and severe to moderate HV (HVA > 20 ) groups) already de ned for each foot in the rst part of the project [12] were used as reference data in the relevant statistical analyzes of nerves in this second part of the project.…”

“…The ring was used as a clock model and a 360° circle model as mentioned previously by Kurtoğlu Olgunus et al 2022 [12]. The data on the ring of right feet were transferred to the clock model as a "mirror image", thus left and right feet could be analyzed together.…”

“…It is also mentioned in various ways that the placement of the tendons changes with the positional change in this bony alignment [3,26]. In our previous study, by modifying Dalmau-Pastor et al's clock model [4], it was possible to statistically evaluate the location of tendons that might be affected by changes in HV [12].…”

“…The aim of the study is to evaluate the distribution of nerves reaching the HV surgical intervention area and to reveal whether the locations of these nerves are affected by the anatomical (bone, joint and tendon related) changes that occur in HV. To describe and analyze the localization of nerves, we used a clock model that we adapted to tendons in our previous study [12] with a exible wire, unlike Dalmau-Pastor et al [4], without cutting the feet.…”