Reconstruction of the plantar toe with a distal reverse instep sensory island flap

A Case Report of Reconstruction of the Great Toe with a Homodigital Island Flap

Homodigital flaps are frequently used in the reconstruction of defects in the fingers. Their use in the coverage of defects of the toes is not commonly reported because such defects are usually treated with skin grafts, proximally based local flaps, or even amputation and shortening of the toe. We describe the implementation of a homodigital island flap of the great toe for reconstruction of a traumatic defect of the dorsal aspect of its distal phalanx.

Free extended posterior tibial artery perforator flap with the neurovascular plexus of a saphenous nerve branch for large soft tissue and sensory reconstruction: Anatomic study and clinical application

BACKGROUND

The posterior tibial artery perforator (PTAP) flap is a useful tool for reconstruction of soft tissue defects in the leg. However, the size and reliability of the flap largely depends on the quality of the perforator by which the flap is supplied, and the sensory recovery of the flap is limited. In this study, the anatomy of the saphenous nerve branches and their accompanying vessels was investigated, and a free extended PTAP flap with the neurovascular plexus of a saphenous nerve branch was designed for large soft tissue and sensory reconstruction in a series of clinical cases.

METHODS

Sixteen adult cadaveric legs perfused with red latex in the femoral artery were dissected. The number and location of the saphenous nerve branches and the features of their accompanying vessels were dissected and studied. From January 2016 to December 2017, six patients with soft tissue defects ranged from 8 × 2.5 cm to 21 × 4 cm were repaired by the free extended PTAP flap. The patients' average age was 48 years. The causes of the defects included machine injuries in three patients and traffic injuries in the other three. The defects located at the hand in three cases, foot in two cases, and ankle in one case. The flap was designed based on the perforators of the posterior tibial artery and included a branch of saphenous nerve. The perforator pedicle and the nerve branch were connected to the vessels and nerve in the recipient site, respectively.

RESULTS

The saphenous nerve gave off 5.8 ± 1.1 branches, with a relatively constant one issuing 8.1 ± 0.7 cm distal to the medial femoral condyle. Every nerve branch had an accompanying vessel, which connected with the PTAPs and supplied the skin. The size of the flap ranged from 10 × 3.5 cm to 23 × 5 cm. All of the flaps survived completely without complications. Follow-up varied from 6 to 12 months. All the patients obtained cold/hot sensation and pain sensation. The results of Semmes-Weinstein monofilament test ranged from 4.31(2 g) to 5.46 (26 g), and the 2-point discrimination test varied from 20 to 35 mm.

CONCLUSION

The free extended PTAP flap, containing the saphenous nerve branch and its accompanying vessels, may be an alternative for large soft tissue reconstruction with improved sensation recovery.

Clinical effect of thumb finger reconstruction using dorsal foot flap transplant for treating thumb defects

It was found that conventional toe graft alone could not meet the patients' needs for wound repair, so we hypothesized that it would be more effective to treat thumb and finger defect by toe graft with dorsalis foot flap. This prospective study was conducted in 104 thumb defect patients to investigate the clinical effect of thumb reconstruction using toe graft with dorsal foot flap for the treatment of thumb defects. These patients were randomly divided into the dorsal foot group and the control group by randomized double-blind method, with 52 patients in each group. The second toe was used for thumb reconstruction transplant in both the groups. After thumb reconstruction, the abdominal pedicled flap was used to repair the surgical wound in the control group whereas the dorsal foot flap was used to repair the surgical wound in the dorsal foot group. Three months after surgery, the efficacy of surgical treatment, evaluation of two-point discrimination, postoperative complications, function of reconstructed thumb, operation time, and hospitalization time were recorded and compared between the two groups. MHOQ questionnaire was used to evaluate and compare the patients' satisfaction with finger reconstruction in both the groups. The surgical therapeutic effect, the function of the reconstructed thumb, and satisfaction with finger reconstruction were significantly higher in the dorsal foot group compared to the control group (all p < 0.05). The postoperative two-point discrimination, postoperative complication rate, operation time, and hospitalization time of patients in the dorsal foot group were significantly lower compared to the control group (all p < 0.05). Thumb finger reconstruction using the second toe transplant with dorsal foot flap had a beneficial effect on thumb defect patients. It can effectively improve finger function and sensory recovery of patients while reducing complications.

Plasticity of Unmyelinated Fibers in a Side-to-end Tubulization Model

BACKGROUND

Histomorphometric studies of unmyelinated fibers of the rat fibular nerves are uncommon, and side-to-end neurorrhaphy studies using the fibular nerve investigate primarily motor fibers. We investigated side-to-end tubulization (SET) technique, in which occurs collateral sprouting from the intact donor nerve fibers to the distal stump of receptor nerve, with muscle reinnervation and functional rehabilitation, to assess whether there is a successful growth of unmyelinated fibers in this model.

METHODS

Adult Wistar rats fibular nerves were sectioned to create a 5-mm gap. A 6-mm silicone tube was attached between a side of the intact tibial nerve and the sectioned fibular nerve distal stump (SET group), with the left fibular nerve as normal (sham group). Seventy days postsurgery, unmyelinated fibers from the distal segment of the fibular nerve were quantified using light and transmission electron microscopy and their diameters were measured.

RESULTS

The number of unmyelinated fibers was similar between sham (1,882 ± 270.9) and SET (2,012 ± 1,060.8), but axons density was significantly greater in the SET (18,733.3 ± 5,668.6) than sham (13,935.0 ± 1,875.8). Additionally, the axonal diameters differed significantly between groups with mean measures in sham (0.968 ± 0.10) > SET (0.648 ± 0.08).

CONCLUSIONS

Unmyelinated fiber growth occurred even with a 5-mm distance between the donor and receptor nerves, reaching similar axonal number to the normal nerve, demonstrating that the SET is a reliable technique that can promote a remarkable plasticity of unmyelinated axons.