Introduction of a New Method for Repair of Widening Surface Scars by Applying the Tenon-Mortise Principle

Abstract

Sir: Scar repair is a common plastic surgery operation. Traditional direct cutting and suturing technique often results in widening scars, which are caused by surgery-generated high local tension, and greatly affect final clinical outcomes. In seeking to reduce incision tension–caused widening scar formation, we applied the classic Chinese wooden architectural tenon-mortise principle to repair widening surface scars. From January of 2006 to December of 2007, 22 cases were treated with this tenon-mortise method by the authors at the Chinese Plastic Surgery Hospital. All scars were in elongated shapes, with widths ranging from 2 to 11 mm (mean, 4 mm). Design incisions along the lesion margins (including a little normal skin tissue). Cut the skin to middle dermal depth and remove the top half scar dermal tissues and the covered scar epidermis. On the retained scar dermal tissues, design the middle cutting line along the lesion longitudinal axis and several vertical crosswise lines at intervals of 0.5 to 0.8 cm. Cut through the scar dermis to the deep layer of subcutaneous tissue along these lines. Dissect both sides of incisions at this layer, and then intermittently remove scar dermal blocks from each side of the middle line, forming tenon structures (Fig. 1). Corresponding mortise structures are formed by removal of identically shaped subcutaneous and partial dermal tissues on the opposite side of its corresponding tenon structure. By suturing each tenon into its corresponding mortise, a tensionless incision closure is readily achieved. Then, suture skin intermittently (Fig. 2).Fig. 1.: (Above) Cut the skin to middle dermal depth and remove the top half scar dermal tissues and the covered scar epidermis. On the retained scar dermal tissues, intermittently remove scar dermal blocks, forming tenon structures. (Below) Corresponding mortise structures are formed by removal of identically shaped subcutaneous and partial dermal tissues on the opposite side of its corresponding tenon structure. By suturing each tenon into its corresponding mortise, a tensionless incision closure is readily achieved.Fig. 2.: Intraoperative views. (Above) The tenon and mortise structures are formed on the retained scar dermal tissues. (Below) By suturing each tenon into its corresponding mortise, a tensionless incision closure is readily achieved.The follow-up period ranged from 6 to 24 months. In this series, redness and hardness of scars usually occurred in the 3 to 6 months after surgery, which was followed by a natural recovery in all cases in the ensuing months. It has always been challenging for plastic surgeons to reduce scar formation at incision sites. It is not rarely seen in the clinic that some surgically revised scars still widen and become hypertrophic over time,1 which led us rethink the underlying mechanism affecting scar formation. Traditional cutting and suturing scar revision methods usually cause a direct cross-incision tension to the healing tissue, so to a certain degree, widening scar forms and affects repair results. For some clinical cases in which satisfying results are achieved for a short period after fine suturing revision operations, widening scars are still seen over a longer period.2,3 To avoid the direct impact of suturing tension on incision edges, Millard modified the traditional method by retaining the scar dermal tissue, folding and suturing it to the opposite subcutaneous tissue.4 This modification effectively reduced scar formation and improved the results of scar revision. Based on Millard’s method, we have incorporated a classic Chinese wooden architectural principle, calling it the tenon-mortise principle, and invented a new method for scar repair. Matured stable scar tissue has the strongest tension-resistant strength. When used in scar repair, it can provide more strength with which to resist incision tension.5 Application of the tenon-mortise technique to repair scar lesions could tightly ligate incision edges; most importantly, it can transfer surgery-generated tension to the normal skin dermal tissue instead of directly impacting on the healing tissues at incisions. Compared with Millard’s method, the described new method has the following advantages: (1) maximal achievement of a seamless connection of dermal tissue; and (2) a more smooth incision closure achieved by mutual insertion of tenon-mortise structures from both sides. Wen Chen, M.D. Shenkai Li, M.D. Yangqun Li, M.D. Qiang Li, M.D. Yong Tang, M.D. Plastic Surgery Hospital Chinese Academy of Medical Sciences and Peking Union Medical College Beijing, People’s Republic of China ACKNOWLEDGMENT The authors thank Dr. Hongwei Cheng for help with article preparation and helpful suggestions.