Background: The aim of this study was to determine the feasibility of the chicken foot model for surgical trainees interested in practising the designing, harvesting and inset of locoregional flaps of the hand. Methods: A descriptive study was performed to demonstrate the technical aspects of harvesting four locoregional flaps in a chicken foot model: fingertip volar V–Y advancement flap, four-flap and five-flap Z-plasty, cross-finger flap and first dorsal metacarpal artery (FDMA) flap. The study was performed in a surgical training laboratory on non-live chicken feet. No participants were involved in this study, apart from authors performing the descriptive techniques. Results: All flaps were successfully performed. Anatomical landmarks, soft tissue texture and flap harvest, as well as inset closely resembled clinical experience with patients. Maximal flap sizes were 12 × 9 mm for volar V–Y advancement, 5 mm limbs for Z-plasties, 22 × 15 mm for cross-finger flaps and 22 × 12 mm for FDMA flaps. The maximal webspace deepening with four-flap/five-flap Z-plasty was 20 mm and the FDMA pedicle length and diameter was 25 and 1 mm, respectively. Conclusions: Chicken feet can be effectively used as simulation models for hand surgical training with respect to gaining familiarity with the use of locoregional flaps of the hand. Further research requires testing for reliability and validity of the model on junior trainees.

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A tighter-than-tolerated fit of aesthetic hand prosthesis is conventionally rectified by stretching the affected segment to plastic deformation. This method is not only time-consuming, but also ineffective in stretching irregular, non-cylindrical prosthesis segments apart from the “wrist and digits”. This study investigates controlled silicone swelling as an alternative method of expanding aesthetic hand and finger prosthesis to address a tight fit. The technique of “controlled” swelling that minimizes oil uptake to as little as is necessary to achieve the desired magnitude of elastomer expansion was demonstrated using experimental test samples. Brush-coats of a cosmetics-grade oil, KF-96A-10CS, 2 a time, were applied on CosmesilTM samples to obtain elastomer expansion. The same technique of staggered oil delivery was used on tight-fitting segments of patients’ prosthesis, with test-fitting of each incremental expansion till satisfactory outcomes were achieved. Percentage circumference increases in swelled test samples and in all rectified/ patients’ prostheses were then compared to validate the effectiveness of the method. Circumference increases in the test samples after each 2 coats were significantly different (P <.001). Representative (unreinforced) Samples 1, 2, and 3 recorded circumferential increases of 4.0% to 11.4% within 30 minute after swelling by 2.6% to 9.7% from 2 to 6 oil coats. This largely correlated with patient data, where circumferential increases of 3.6% to 9.5% from 2 to 6 oil coats were collectively recorded in all fit-rectified finger prostheses. Swelling in the expanded proximal segment of all 24 finger prostheses was estimated to be within 9.7%. Of these, 22 (92%) required 2 to 4 oil coats, inferring a lower still swelling of 6.5%. The rapid and consistent elastomer expansion enabled prosthetic fit rectification to be achieved in a much shortened time. Clinical outcomes indicated that low swelling magnitudes involving small amounts of 2 to 6 brush-coats of oil have no adverse effects on the prostheses. None of the participating patients had reported any incidence of discernible change in all of the important properties of their prostheses. Outcomes based on the CosmesilTM-KF-96A-10CS elastomer-oil combination demonstrated that controlled silicone swelling involving minimal use of oil is an effective method of intervention for a tighter-than-tolerated prosthetic fit of silicone hand and fingers.

Introduction Vessel repair in a chicken thigh is commonly used in microsurgery training model. The sciatic nerve is closely associated with the vessels and has been used for training nerve coaptation, which has different technical considerations from vessel anastomosis. We describe in detail the relevant surgical anatomy and training exercises that can be used with this model. Methods With 32 fresh store-bought chicken thighs, 16 were used to analyze the gross and histological features of the sciatic nerve, and 16 were intended to create and perform training models. Results The average visible length of the nerve in the thigh was 51 mm (standard deviation [SD] 2.57 mm). The average diameter of the nerve was 2 mm (SD 0.33 mm) and was largest at its proximal end (3.21 mm, SD 0.27 mm). The nerve consistently branched into two along the chicken thigh, with more branching subsequently. This simulation model is appropriate not only for the classical end-to-end epineural suture, but also for advanced exercises, in terms of longitudinal fasciculus dissection, mismatched size nerve transfer, injured nerve preparation, and vein conduit technique. Dyeing of nerve fascicles enhanced the visibility of nerve surface quality. Conclusion The sciatic nerve in the chicken thigh is a suitable and accessible model for microsurgery training. The branching and fascicular patterns of the nerve lends itself well to both novice training and advanced simulation. We have incorporated this model into our training curricula.

Plastic and Reconstructive Surgery • June 2022 performance and learning. 4 This is contingent on valid and reliable assessment of the training task. SParTA is a product scoring system that fulfils this requirement for microsurgical training.