[Repair methods and clinical effects of full-thickness burn wounds deep to tendon or even bone in fingers]

Objective: To explore the repair methods and clinical effects of full-thickness burn wounds deep to tendon or even bone in fingers. Methods: A retrospective non-randomized controlled trial was conducted on the 98 patients with full-thickness finger burns deep to tendon or even bone who met the inclusion criteria and were hospitalized in Xiangya Hospital of Central South University from January 2010 to December 2019. Among the 98 patients, there were 81 males and 17 females, aged from 1 to 72 years, with 160 fingers involved. The wound area of each of affected fingers ranged from 2.0 cm×1.5 cm to 12.0 cm×3.5 cm, and the maximum wound area after merging the affected fingers was 12.0 cm×10.0 cm. For adult hands with multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers or children with full-thickness finger burns deep to tendon or even bone, pedicled abdominal flaps were selected. For adults with single or two fingers with full-thickness burns deep to tendon or even bone, the pedicled internal hand flaps and free tissue flaps were selected. The free tissue flap repair requires good vascular conditions in the recipient area with arteries and veins available for anastomosis. For thumb nail burns deep to tendon or even bone or partial absence of the thumb after burns, the thumbs were reconstructed with the first toenail flap or dorsal foot flap with the second toe. In this study, 45 pedicled abdominal flaps were used to repair the wounds in 91 fingers, 37 pedicled internal hand flaps were used to repair the wounds in 37 fingers, 26 free tissue flaps were used to repair the wounds in 28 fingers, 3 first toenail flaps were used to reconstruct 3 patients' thumb nails and to repair hand wounds, and 1 dorsal foot flap with the second toe was used to reconstruct 1 patient's thumb and to repair hand and wrist wounds. The tissue flap area was from 2.0 cm×1.5 cm to 20.0 cm×10.0 cm. The wound in the donor site was repaired by direct suture or full-thickness skin grafting from the medial upper arm of the affected limb or split-thickness skin grafting from the outer thigh. The postoperative survival of the tissue flap, postoperative complications, and appearance and function of the flap donor site were observed. For the patients who were followed up, their finger functions were evaluated at the last follow-up using the trial criteria for replantation function evaluation of the amputated finger issued by the Hand Surgery Society of the Chinese Medical Association, and the satisfaction of the patients was investigated using the Efficacy Satisfaction Scale. Data were statistically analyzed with Kruskal-Wallis H test and Nemenyi test. Results: Of the 112 tissue flaps, 104 tissue flaps survived completely and had good blood circulation; 1 pedicled thumb dorsal ulnar reverse island flap, 1 pedicled finger artery cutaneous branch reverse island flap, and 1 free grafted anterolateral thigh perforator flap were slightly necrotic at the end, which were repaired with outer thigh split-thickness skin graft after dressing change and granulation tissue growth; 2 free grafted tarsal external artery flaps and 1 pedicled thumb dorsal ulnar reverse island flap suffered from postoperative venous return obstruction, which survived after partial suture removal and heparin saline cleansing of the wound; 1 pedicled modified dorsal metacarpal artery retrograde island flap and 1 free grafted peroneal artery perforator flap were necrotic, which were repaired by a pedicled abdominal flap and a lateral upper arm flap free transplantation respectively in stage Ⅱ. After transplantation, the tissue flaps had good shape, soft texture, and good elasticity, without bloating. There was no functional disorder in the flap donor site, and only slight scar remained. A total of 117 fingers of the 72 patients received 3-24 months of outpatient or telephone follow-up. At the last follow-up, the excellent and good rates of function evaluation of fingers repaired with pedicled abdominal flap, pedicled internal hand flap, and free tissue flap were respectively 77.3% (51/66), 96.3% (26/27), and 95.8% (23/24). The function of fingers repaired with free tissue flap and pedicled internal hand flap was significantly better than that with pedicled abdominal flap (P<0.01). The satisfaction of patients with fingers repaired by free tissue flaps was significantly higher than that by pedicled abdominal flap (P<0.05). Conclusions: According to the specific situation of full-thickness burn wounds deep to tendon or even bone in fingers, the pedicled abdominal flap is used to repair the multiple full-thickness burn wounds deep to tendon or even bone in multiple fingers of adult or the full-thickness burn wounds deep to tendon or even bone in fingers of children, the pedicled internal hand flap or free tissue flap is used to repair the full-thickness burn wounds deep to tendon or even bone in single or two fingers of adult patients, and the first toenail flap or the dorsal foot flap with the second toe is used to reconstruct the thumbs with full-thickness burn deep to tendon or even bone, with high postoperative tissue flap survival rate and few complications. The functional recovery of the affected finger is better after repair with free tissue flap and pedicled internal hand flap, and the patients' satisfaction is the highest after free tissue flap repair.