LAUSR

(1) Reinnervation and sensory recovery of skin are important in protecting from injury [2]. Semmes–Weinstein monofilament (5–0 monofilament which exerts 10 g of pressure) test is the gold standard for assessing touch, but the authors have used cotton wick which does not exert quantifiable pressure. (2) Sensory assessment is ideally and objectively graded by British Medical Research Council (MRC) scoring system (range = S0–S4) which can be used to quantify the results. (3) Protective sensation includes touch, pain, pressure and temperature; therefore, all these should have been assessed. Loss of pain and temperature sensations can lead to painless burns. (4) Skin grafts regain their sensory innervation from the graft bed and from the edges of the defect by the regeneration of nerve endings [3]. This could have been an important part of discussion; it will be interesting to know the authors’ response. (5) Many authors believe that skin graft is reinnervated primarily by unmyelinated fibres which transmit the perception of gross touch sensation, pain and temperature. The more sophisticated finer sensations such as light touch, vibration and two-point discrimination are transmitted only by heavily myelinated fibres and specialised sensory receptors which are not found in grafts. [3] (6) Authors have measured—pre-operatively—tactile sensibility at the donor site, at the recipient site, at contralateral site and skin surrounding the soft tissue defect. It is important to know as the returning sensation in a skin graft retains the sensory pattern of the donor site or recipient site. However, the authors have not commented on this point in the results and discussion sections. (7) Similarly, ability of the skin graft to sweat prevents them from getting dry and future breakdown. Sweating function returns at the same time as does the regeneration for pain and touch; its recovery could have been added. (8) The authors did sensory assessment at 7th PO day which appears too early for neural communication to be established in the graft. Early recovery seen at 1 week in 23.9% patients is more likely to be representing the wound margin phenomenon rather true return of 2-PD in the graft. This is substantiated by the fact that delays in return of protective sensations in patients who developed oedema and scar tissue in the graft bed or when graft was applied over exposed fascia or tendons. ‘Neuronal’ status of graft bed is a very important determinant. (9) It is interesting to know if return of vibration threshold which is a function of large fibres and along with perception threshold, touch by Semmes–Weinstein monofilament and 2-PD substantially increases the sensitivity and specificity for prediction of ulceration.