Anatomic study of the dorsalis pedis artery, first metatarsal artery, and second metatarsal bone for mandibular reconstruction

Abstract

The dorsalis pedis flap is currently widely used for its versatility and efficiency. A full understanding of the anatomic position of the dorsalis pedis artery and its continuity to the first metatarsal artery is crucial for the success and survival of the flap. However, the anatomy of the dorsalis pedis and first metatarsal arteries varies greatly between individuals. It is also possible to form osteocutaneous flaps from dorsalis pedis flaps, but thus far no studies have investigated their anatomic form and the trabecular: cortical bone ratio (TBR). The purpose of this study was to clarify the anatomic variation of the dorsalis pedis and first metatarsal arteries by cadaver dissection, and to define the TBR of the second metatarsal bone to ascertain their suitability for implants.Fifty-two specimens were prepared for this study. Each of the specimens was dissected on the dorsal side of the foot to search for the dorsalis pedis artery. The foot was then cut on the coronal side, and the second, third, and fourth metatarsal bones were removed to reveal the path of the first metatarsal artery in relation to first dorsal interosseous muscle. The second metatarsal bone was then cut on five sides and scanned with a photograph scanner, and the TBR was calculated using image analysis software. The data were analyzed statistically using ANOVA and paired t-tests.Three types of the dorsalis pedis artery were found: (1) type A was the most common (94.1%), in which the artery continuously formed the first metatarsal artery, (2) the next was type C (3.9%), in which the artery ran below the first dorsal interosseous muscle, without revealing the first metatarsal artery on the superficial side, and (3) in type B (1.9%), the artery ran from the lateral side. Five variations of the first metatarsal artery were identified: Ia-c, and IIa and b. The most common was type IIb

(30%), in which the artery ran below the first dorsal interosseous muscle, followed by type Ib (22%), in which the artery ran obliquely through the muscle, and type Ic (22%), in which the artery ran parallel to the muscle, IIa (18%), in which the artery ran above and below the muscle, and type Ia (8%), in which the artery only ran above the muscle. The second metatarsal bone was divided into five parts (1-5), and the TBR was calculated in all parts. There was no trabecular bone in regions 1 and 5, which were 10 mm from the edges of the base and head, respectively, in any of the specimens. The TBR appeared to be lower in region 3 (which was the middle of the body) than in regions 2 and 4, and highest in region 2; however, the differences were not statistically significant (P>0.05). All regions of the second metatarsal bone appear to be suitable for implants, but when placing the implant in the proximal end, care should be taken not to overheat the bone and to be wary of perforation when placing it on the middle side.