Current trends in digital replantation-a narrative review.

Background and Objective: Digital replantation for traumatic amputation has become the standard of care with advances in microsurgical techniques and technology. While digital replantation has progressed significantly, there are still gaps in knowledge in many aspects. Some of the controversial topics in digital replantation include the indications and contraindications, anesthesia, number of vessel anastomoses, mechanism of injury, role of vein graft, distal fingertip replantation, and postoperative management. This article is a narrative review that discusses these controversies and current issues pertaining to digital replantation. Methods: PubMed, Web of Science, and Google scholar were searched using keywords relating to "digit replantation", "amputation", and "digital replant" with the following terms: "indications", "contraindications", "anaesthesia", "survival", "vessels", "mechanism of injury", "vein graft", "outcome", and "thrombophylaxis". Relevant articles pertaining to digital replantation and deemed by the authors as current or controversial were included. Key Content and Findings: The reported survival rates of digital replantation are high. With the advancement of microsurgical techniques and technology, the boundaries of digital replantation continue to be pushed. Various methods have been described recently to improve the success rates of difficult replants, such as strategies for venous outflow and vein grafting. However, there are still aspects of digital replantation that remain unanswered, such as the number of veins to anastomose and the thromboprophylaxis regime. Conclusions: The review delves into controversial aspects of digital replantation, including contraindications, anesthesia, and postoperative management. Indications and contraindications will continue to evolve alongside advancements in microsurgical techniques and anesthesia. It highlights key factors influencing survival rates, such as the number of repaired vessels and the mechanism of injury. Finally, the review consolidates strategies for managing challenging digital replantations.

Development and Validation of a Low-Cost Drilling Model.

Background: Simulation models enable learners to have repeated practise at their own time, to master the psycho-motor and sensory acuity aspects of surgery and build their confidence in the procedure. The study aims to develop and evaluate the feasibility of a low-cost drilling model to train surgeons in the drilling task. The model targets three aspects of drilling - (1) Reduce plunge depth, (2) Ability to differentiate between bone and medullary canal and (3) Increase accuracy drilling in various angles. Methods: This cross-sectional study was conducted after obtaining ethics approval. We invited Consultants in the field of Orthopaedic or Hand Surgery to form the 'expert' group, and the 'novice' group consisted of participants who had no prior experience in bone drilling. We developed a drilling simulator model made from a polyvinyl chloride (PVC) pipe filled with liquid silicone. This model cost less than US$5. An electric Bosch drill (model GBM 10 RE) with a 1.4 mm K-wire 10 cm in length (6.5 cm outside the drill) was used for drilling. The main outcomes of the study were time taken for drilling, plunge depth, ability to penetrate the far cortex and accuracy. Results: Thirty-one participants were recruited into the study, of which 15 were experts and 16 were novices. The experts performed significantly better for plunge depth (t = -3.65, p = 0.0003) and accuracy (t = -2.07, p = 0.04). The experts required 20% less time to complete the drilling tasks, but it was not statistically significant (t = -0.79, p = 0.43). Conclusions: The low-cost drilling model could be useful in training Residents in the drilling task. It will allow Residents to practise independently at their own time and assess their own performance.

Salvage of failed proximal interphalangeal arthroplasty with vascularised toe joint transfer: Report of two cases.

Failed implants of the proximal interphalangeal joint may result in bone and soft tissue deficits and joint instability with limited reliable options for reconstruction besides an arthrodesis procedure. The purpose of this report is to illustrate the use of vascularized second toe joint for salvage of failed, multi-operated proximal interphalangeal joint in two active patients. Pre-existing scars are used to define the approach and choice of donor site. Flow through anastomosis was performed on the finger digital artery. At final follow-up, the transplanted joints achieved 80-90 degrees of motion and the patients were able to return to their desired level of activities. The procedure is a good alternative for the fit patient wanting to achieve a stable finger with preservation of motion in catastrophic failure of prosthetic proximal interphalangeal joint arthroplasty.

The stacking concept: cannulated screws for extra-articular metacarpal base fracture of the thumb.

An alternative technique to treat extra-articular fractures of the base of the first metacarpal with intramedullary canulated headless screws is presented. The principle is creating an internal fixator within the medullary canal by introducing multiple retrograde screws until they have jammed.

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.

Collapse after Carpal Bone Tunneling. An Underreported Complication?

PURPOSE: To report the complication of carpal bone tunnel collapse in scapholunate reconstruction. METHODS: The authors present six cases of carpal collapse or bone necrosis after bone tunneling for ligamentous reconstruction, three in the scaphoid bone and three in the lunate. RESULTS: All six cases were secondary to ligament reconstruction for chronic scapholunate dissociations, none of which had preoperative structural scaphoid or lunate deformities. CONCLUSIONS: Although the incidence of this occurrence is unknown, the consequences could be substantial; therefore, patients should be warned of this possibility when discussing complications of ligament reconstruction for chronic scapholunate instability requiring the creation of a bone tunnel. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

The epidemiology and distribution of hand fractures in Singapore.

Introduction: The aim of this study was to elucidate the epidemiology and distribution of hand fractures in Singapore. Methods: A total of 701 hand fractures in 596 patients aged 21 years and above from a single centre were reviewed from 2010 to 2011. Details regarding the patient demographics, occupation, mechanism of injury, associated injuries and treatment were obtained. Results: Hand fractures were particularly significant in patients between the ages of 21 and 40 years 58.9% of the total cases. The relative risk of hand fractures in males was 5.5 times greater than that in females. The majority of hand fractures occurred at the workplace (47.7%), with crush injury being the main mechanism of injury (33.6%). The most common locations of hand fracture were the little finger ray (31.2%) and distal phalanges (37.7%). There were 170 cases that underwent surgical fixation, which accounted for 24.3% of all fractures. Fixation rate was similar for both closed and open fractures but was significantly higher in the proximal and middle phalanges compared to the distal phalanx and metacarpal (P < 0.001). With regards to surgical fixation methods, wires were commonly used in either tuft fractures (100.0%) or intra-articular fractures (69.9%), whereas plates and screws were commonly used in shaft fractures (65.5%). Conclusion: The most significant population that sustained hand fractures in Singapore are young to middle-aged males who are skilled manual workers. The most commonly involved ray and location of hand fractures are the little finger ray and the distal phalanges, respectively, as they are in a relatively more exposed location.

Chicken Feet: A Model for Practising Locoregional Flaps of the Hand.

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.

Radioscaphoid Impingement after Volar Plate Fixation and Bone Grafting of a Non-United Scaphoid Fracture.

Volar plate fixation (VPF) of scaphoid fractures has received increased attention over the past decade. The purported benefits over headless screw fixation are increased rigidity, better purchase of small fragments, the ability to prevent extrusion of bone graft, and to act as a buttress against excessive scaphoid flexion. We report a case of symptomatic radioscaphoid impingement presenting two years after successful VPF for a non-united scaphoid fracture. We performed an arthoscopic evaluation, synovectomy and chondroplasty, followed by open radial styloidectomy and implant removal. This article highlights the pertinent clinical features, relevant imaging, and key intra-operative findings. We have analyzed the factors that led to this complication and have highlighted several technical tips to minimize radiocarpal impingement and ongoing chondral damage.

3D-printed Poly-Lactic Co-Glycolic Acid (PLGA) scaffolds in non-critical bone defects impede bone regeneration in rabbit tibia bone.

BACKGROUND: An increasing number of bone graft materials are commercially available and vary in their composition, mechanism of action, costs, and indications. OBJECTIVE: A commercially available PLGA scaffold produced using 3D printing technology has been used to promote the preservation of the alveolar socket after tooth extraction. We examined its influence on bone regeneration in long bones of New Zealand White rabbits. METHODS: 5.0-mm-diameter circular defects were created on the tibia bones of eight rabbits. Two groups were studied: (1) control group, in which the bone defects were left empty; (2) scaffold group, in which the PLGA scaffolds were implanted into the bone defect. Radiography was performed every two weeks postoperatively. After sacrifice, bone specimens were isolated and examined by micro-computed tomography and histology. RESULTS: Scaffolds were not degraded by eight weeks after surgery. Micro-computed tomography and histology showed that in the region of bone defects that was occupied by scaffolds, bone regeneration was compromised and the total bone volume/total volume ratio (BV/TV) was significantly lower. CONCLUSION: The implantation of this scaffold impedes bone regeneration in a non-critical bone defect. Implantation of bone scaffolds, if unnecessary, lead to a slower rate of fracture healing.

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.

Outcomes of Phalangeal Neck Fractures in a Pediatric Population.

PURPOSE: Displaced pediatric phalangeal neck fractures are regarded as unstable, and hence, surgical fixation is traditionally recommended. In our experience, some patients with displaced fractures treated nonsurgically healed with a good clinical outcome and no further displacement. We studied the outcome of displaced phalangeal neck fractures treated nonsurgically with attention to the change in fracture displacement over time and hypothesized that displaced phalangeal neck fractures can be treated nonsurgically with maintenance of acceptable radiological parameters. METHODS: A retrospective review of 35 patients aged 16 and younger was conducted. Included patients had at least 10° of angulation or 25% translation in either the coronal or the sagittal plane, with no malrotation. Angulation and translation of the distal fracture fragment in the coronal and sagittal planes was measured from radiographs taken at 2 intervals-within 7 days of the injury and at least 21 days after the injury. Initial and final measurements were compared to determine the amount of fracture displacement that occurred. RESULTS: Thirty-five patients with type II A, B, and C fractures (classification according to Al-Qattan) comprised our study sample. Twelve patients had undergone manipulation and reduction. Average radiological follow-up was 4.3 months (range, 0.7-86 months; median, 1.2 months; SD, 14.7). These fractures treated nonsurgically did not displace as the fracture healed, suggesting that type II fractures, although traditionally regarded as unstable, may maintain their radiological parameters without surgical fixation. CONCLUSIONS: Our findings suggest that displaced phalangeal neck fractures do not necessarily displace with nonsurgical treatment. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.

VY Advancement, Thenar Flap, and Cross-finger Flaps.

The VY advancement, thenar flaps, and cross-finger flaps are workhorse flaps used in reconstruction of fingertip defects. They are reliable and simple to raise without need for microvascular dissection. In addition, they usually provide good results in terms of sensibility and range of motion. This article reviews the history, anatomy, and surgical technique of these flaps with a focus on aesthetic refinements with illustrative cases.

Maximal advancement of homodigital neurovascular island flaps.

We investigated the maximal advancement of the homodigital neurovascular island flap with the digit in full extension and its correlation to the digital length. In 32 adult cadaveric digits, flaps measuring 1 × 1 cm were sequentially elevated to different dissection points. Dissection of the flap to the proximal interphalangeal joint crease, palmo-digital crease, division of adjacent digital artery and the superficial arch resulted in flap advancement of 8, 12, 15 and 18 mm, respectively. The degree of advancement correlated to the length of the finger and was approximately 19% of the finger length. We conclude that dissection of a homodigital antegrade neurovascular island flap to the proximal interphalangeal joint, palmo-digital crease, after ligation of adjacent digital artery and the superficial arch allows progressively more advancement. The advancement obtained by flap dissection to the palmo-digital crease was about 19% of the finger length.

Treatment of Carpal Instability and Distal Radioulnar Joint Instability.

Carpal instability and distal radioulnar joint instability represent an important set of conditions responsible for pain and disability in the wrist. Either condition can occur as a result of ligamentous failure or loss of articular congruity from fractures or a combination of both. Instability itself is a clinical diagnosis supported by relevant imaging modalities. Carpal and distal radioulnar joint instability needs to be considered according to its stage and severity as well as other factors like etiology and chronicity to determine the optimal treatment option. This article summarizes the conditions most relevant to the practice of a hand surgeon, with emphasis divided equally between assessment and diagnosis, staging, and treatment. The 3 most common carpal instability conditions are outlined in this article together with a review on acute and chronic distal radioulnar joint instability.