Surgical Anatomy and Exercises Using the Chicken Thigh Sciatic Nerve for Microsurgery Training.

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.

Novices can assess microsurgery performance, and this is enhanced using the Manual Suture Parameters for Training and Assessment (M-SParTA) scoring system.

This study explores how novices could effectively evaluate the quality of microsurgical suturing. That would be enhanced with using a novel Manual Suture Parameters for Training and Assessment (M-SParTA), which supported novices with guidance on the objective parameters, in order to increased the accuracy of scoring ability. We also propose the following initial framework to train novices in microsuturing using a standardised task: 1) Exposure; 2) Assessment; 3) Hands-on and self-assessment. The independent learning cycle with targeted supervision provides novices with greater autonomy and a less stressful environment that could enhance skills training.

A Comparison of Casting Versus Splinting for Nonoperative Treatment of Pediatric Phalangeal Neck Fractures.

BACKGROUND: Phalangeal neck fractures account for 13% of pediatric finger fractures. Al Qattan type I (undisplaced) fractures are treated nonoperatively. There is increasing evidence that Type 2 (displaced) fractures achieve remarkable fracture remodeling with nonoperative treatment and patients frequently make a full functional recovery. The options available for nonoperative management of these fractures are either a plaster cast or a removable splint. We hypothesized that there would be no significant difference in radiologic outcome in pediatric phalangeal neck fractures (Types I and II) treated with splint or cast immobilization. METHODS: This is a retrospective study of patients aged 18 and below with phalangeal neck fractures treated nonoperatively from 2008 to 2017. Radiographs were compared at <1 week and >3 weeks after injury. Translation and angulation in coronal and sagittal planes were measured and compared using Student t tests. Baseline variables were compared using χ or Fisher exact tests. RESULTS: There were 47 patients with phalangeal neck fractures treated nonoperatively during the study period. There were 9 type I and 38 type II fractures. The mean age was 10 years with 40 males and 7 females. Fractures occurred in 33 dominant and 14 nondominant hands and involved 29 proximal and 18 middle phalanges. Nineteen children were treated in casts and 28 with removable splints. The mean duration of follow-up was similar between the 2 groups. The most affected phalanx was the proximal phalanx of the small finger and the most common fracture pattern was type IIA. There was no significant difference in clinical and radiologic outcomes between children who were treated in casts and those treated in removable splints. CONCLUSION: There was no difference in the clinical and radiologic outcomes in pediatric phalangeal neck fractures treated with cast or splint immobilization. Splinting has the added benefits of increased comfort and hygiene and we routinely offer splinting as a viable alternative in the nonoperative treatment of Al Qattan type I and type II phalangeal fractures. TYPE OF STUDY/LEVEL OF EVIDENCE: Level III-therapeutic studies.

Management of Tendon and Bony Injuries of the Distal Phalanx.

Acute tendon and bony injuries of the distal phalanx are challenging injuries because they may result in chronic pain, hypersensitivity, stiffness, and deformity if they are not adequately treated. Flexor tendon avulsions require early surgical repair. Conversely, most extensor tendon injuries and fractures heal well with nonoperative treatment. However, surgery is indicated in selected patients, and meticulous technique is required to achieve good postoperative outcomes. In this article, we outline the pertinent clinical anatomy of the distal phalanx, review the current literature regarding treatment options, and highlight key management points to ensure good clinical outcomes while minimizing complications.

Pediatric Hand and Wrist Fractures.

Hand and wrist fractures are common in the pediatric population. Accurate diagnosis relies on the understanding of the physeal anatomy and carpal ossification. Treatment of these fractures is largely influenced by physeal biology and compliance with treatment. A majority have a favorable outcome with nonoperative treatment. Operative treatment should be considered in patients with clinical deformity, open fractures, and significant fracture displacement. Physeal-friendly surgical approaches and implants should be used to minimize the sequelae of physeal injury.

The effects of bi-functional anti-adhesion scaffolds on flexor tendon healing in a rabbit model.

Progressive tendon adhesion is a major challenge in flexor tendon repair. The authors developed a bifunctional anti-adhesion scaffold and hypothesized that its application would reduce adhesion formation and deliver mesenchymal stem cells (MSCs) to enhance tendon healing. The scaffold was fabricated by an electrospinning machine before surface modification. The flexor tendons of 29 New Zealand rabbits underwent surgical repair and randomized to control, scaffold and scaffold loaded with MSC group. At 3 and 8 weeks post-surgery, range of motion (ROM), biomechanical properties, and histology were examined. There was no significant increase in ROM and biomechanical properties between the three groups. The histology showed successful delivery of MSCs but no significant difference in nuclear morphometry. This barrier delivers and retains MSCs within the tendon repair site. However, its sheet form and wrapping around the repair site may not be optimal for tendon healing. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 2605-2614, 2018.

The Effects of Autologous Platelet-Rich Fibrin on Flexor Tendon Healing in a Rabbit Model.

PURPOSE: Platelet-rich plasma containing large amounts of growth factors is purported to increase repaired flexor tendon strength. However, the use of bovine thrombin has the risk of antibody formation. We evaluated the effects of the newer generation autologous platelet-rich fibrin (PRF) on flexor tendon healing. METHODS: We performed surgical repair of 32 flexor tendons from the index and ring digits of the hind paws of 8 New Zealand white rabbits. In the PRF group, the PRF membrane was either wrapped around or interposed between the repair sites. At 3 weeks after surgery, the tested tendons were subjected to range of motion analysis, cross-sectional area measurement, biomechanics testing, and histological analysis. RESULTS: The results showed no significant increase in range of motion in the PRF group compared with the control group, but there was a significant increase in cross-sectional area of the tendons in the PRF group. The biomechanical testing suggested that the control had a higher load to failure and stress to failure but similar stiffness and modulus to the PRF group. CONCLUSIONS: The PRF did not have a major influence on cellular organization. It also had an undesirable effect on the biomechanical properties of repaired flexor tendons. CLINICAL RELEVANCE: The findings of this study suggest PRF may, in certain situations, hinder rather than enhance, the healing for repaired flexor tendons.