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.

Bilobed Flap Coverage for the Reconstruction of Dorsal Soft Tissue Defect Over the Proximal Phalanx: A Case Report.

Soft tissue defects over the dorsal finger are common and may result from trauma, burns, or surgical management of infections and tumors. We present a case where a bilobed flap was used for the reconstruction of a soft tissue defect dorsal to the proximal phalanx of the ring finger and discuss the design of this flap. The defect was secondary to a collar button abscess of the right third webspace and the surgical debridement required to control the infection. The exposed extensor tendon over the proximal phalanx required coverage. The bilobed flap was designed with the first lobe over the right middle finger proximal phalanx and the second lobe over the right second webspace and index finger. The flap healed uneventfully and the patient had good functional recovery. This design for a bilobed flap is suitable for soft tissue reconstruction of defects over the dorsum of the proximal phalanx. It is a simple, reliable, single-staged procedure that provides like-for-like reconstruction and has minimal donor site morbidity.

The role of reconstructive microsurgeons in liver transplantation-a narrative review.

Background and Objective: Liver transplantation is a life-saving procedure, but also associated with complications. Hepatic artery thrombosis is one of the most devastating complications, especially for living donor liver transplantation. The application of microsurgical techniques for hepatic artery reconstruction has greatly reduced the risk of hepatic artery thrombosis. In this narrative review, we discuss the technical considerations and challenges faced in microsurgical reconstruction of hepatic artery in liver transplantation. Methods: PubMed, Web of Science, and Google Scholar were searched for keywords relating to "liver transplantation", "microsurgery", "living donor liver transplantation", "deceased donor liver transplantation", "hepatic artery", "hepatic artery thrombosis", "hepatic artery reconstruction" and "microsurgical anastomosis". Relevant articles pertaining to the technical considerations and challenges of microsurgery in liver transplantation were included. Key Content and Findings: The conditions of liver transplantation pose unique challenges to the microsurgeon. Nonetheless, there are described strategies that can overcome these conditions, as well as technical details that may improve the outcomes of hepatic artery reconstruction. These strategies start from proper positioning of the patient, conscientious selection of donor and recipient hepatic vessels, and minimizing movements during critical microsurgical anastomosis. Technical details include techniques to overcome vessel delamination, size mismatch, poor quality vessels, and short vessel stump. This review also explores the outcomes of microsurgical hepatic arterial reconstruction. Conclusions: There are various strategies to mitigate the challenges of microsurgery in liver transplant. Microsurgery improves the outcome of liver transplantation. Microsurgeons will continue to be a priceless resource that all liver transplant teams should have.

Positive Ulnar Fovea Sign - Audit of Patient Outcomes Following Nonsurgical and Surgical Management.

Background: Patients with ulnar-sided wrist pain and positive ulnar fovea sign are usually treated nonsurgically before surgical options are considered. However, the outcomes of nonsurgical management are unknown. Many of these patients also have unstable distal radioulnar joint, but there has been no comparison between the outcomes of these patients with stable and unstable distal radioulnar joint. The objectives of this study are to (1) determine the outcomes of nonsurgical and surgical treatment of patients with positive ulnar fovea sign, and (2) compare the outcomes of patients with stable and unstable distal radioulnar joint. Methods: A retrospective analysis of the outcomes of patients with ulnar sided wrist pain and positive fovea sign was performed from March 2009 to December 2014. Outcomes were measured based on patient-reported pain improvement, grip strength and range of motion of the affected wrist before and after treatment. A total of 100 wrists in 98 patients were reviewed. Results: 54% of wrists managed nonsurgically experienced pain improvement. 83% of wrists managed surgically experienced pain improvement. The mean grip strength increased by 2.8 kg and 2.7 kg, while the range of motion decreased by 14° and 5° after nonsurgical and surgical treatment respectively. When comparing patients with stable and unstable distal radioulnar joint, there were statistically more wrists with unstable distal radioulnar joint that experienced pain improvement after treatment. Conclusions: The study showed that there is a role for nonsurgical treatment for wrists with positive ulnar fovea sign with more than half of the patients experiencing pain improvement. We also found that positive ulnar fovea sign patients with unstable distal radioulnar joint had better pain outcomes compared to those with stable distal radioulnar joint.

Clinical Outcomes of Zone 2 Flexor Tendon Repairs Using the Modified Lim/Tsai Technique.

BACKGROUND: The single looped suture modified Lim/Tsai technique is widely used for flexor tendon repairs. It has been shown to possess better biomechanical properties and require less repair time per tendon as compared to the double looped suture original Lim/Tsai technique. However, there is no clinical data on the modified technique. METHODS: The retrospective study included zone 2 flexor tendon repairs made using the modified Lim/Tsai technique from January 2008 to December 2014. Clinical outcome was assessed using the revised Strickland and Glogovac criteria, which categorises repairs based on the total active motion of the repaired digit. RESULTS: Sixty-two patients with 74 digits were included. The overall mean total active motion was 122°. The overall satisfactory outcome of the modified Lim/Tsai technique was 81.1%. The rupture rate of the modified Lim/Tsai technique was 2.7%. Using multivariate linear regression model, we found that outcomes were negatively influenced by subzone 2C and crush/saw injuries, but not by concomitant neurovascular injuries or post-operative follow-up duration. CONCLUSIONS: Based on this retrospective study of patients with zone 2 flexor tendon injuries, the clinical outcomes of modified and original Lim/Tsai techniques are comparable. As such, there is no clinical evidence favouring one over the other.

A review of cyclic testing protocols for flexor tendon repairs.

BACKGROUND: Cyclic testing of flexor tendons aims to simulate post-operative rehabilitation and is more rigorous than static testing. However, there are many different protocols, making comparisons difficult. We reviewed these protocols and suggested two protocols that simulate passive and active mobilization. METHODS: Literature search was performed to look for cyclic testing protocols used to evaluate flexor tendon repairs. Preload, cyclic load, number of cycles, frequency and displacement rate were categorised. FINDINGS: Thirty-five studies with 42 different protocols were included. Thirty-one protocols were single-staged, while 11 protocols were multiple-staged. Twenty-nine out of 42 protocols used preload, ranging from 0.2 to 5 N. Preload of 2 N was used in most protocols. The cyclic load that was most commonly used was between 11 and 20 N. Cyclic load with increment of 10 N after each stage was used in multiple-staged protocols. The most commonly used number of cycles was between 100 and 1000. Most protocols used a frequency of <1 Hz and displacement rate between 0 and 20 mm/min. INTERPRETATION: We propose two single-staged protocols as examples. Protocol 1: cyclic load of 15 N to simulate passive mobilization with preload of 2 N and 2000 cycles at frequency of 0.2 Hz.; Protocol 2: cyclic load of 38 N to simulate active mobilization, with the same preload, number of cycles, and frequency as above. This review consolidates the current understanding of cyclic testing and may help clinicians and investigators improve the design of flexor tendon repairs, allow for comparisons of different repairs using the same protocol, and evaluate flexor tendon repairs more rigorously before clinical applications.

Acute ulnar nerve compression associated with pisiform fracture - a case report and literature review.

We evaluated a case of pisiform fracture with ulnar nerve compression managed with pisiformectomy. At 11 months' follow-up, the patient regained range of motion of the wrist and grip strength with no subjective loss of function and normal nerve conduction study. We compared other treatment modalities and reviewed their outcomes.

Flexor Tendon Injuries and Repairs: A Single Centre Experience.

BACKGROUND: Although flexor tendon injuries cause significant morbidities and socio-economic implications, there have been limited data on patient demographics, injury characteristics and surgical details. The aim of this study is to describe our experience in flexor tendon injuries and repairs. METHODS: We performed a retrospective study of all digital flexor tendon injuries that were repaired from January 2011 to December 2014. The collected data included patient demographics, injury characteristics and surgical details. RESULTS: A total of 214 patients, 308 digits with 446 flexor tendon repairs were identified. We found that males, non-residents, and 20-29 age group were most prone to flexor tendon injuries. Cleaners, labourers and related occupations were the most vulnerable. The mechanism of injury was usually work-related and mostly caused by glass. Most injuries involve both flexor digitorum profundus and flexor digitorum superficialis tendons. Concomitant digital nerve and vessel injuries were common. Most patients suffered zone 2 laceration of a single digit of the non-dominant hand. Most patients underwent procedures that lasted 1 to 2 hours, including multiple flexor tendon repairs, microsurgical repairs and other interventions. CONCLUSIONS: This study is the largest study on patient demographics, injury characteristics and surgical details on flexor tendon injuries and repairs. It could be used to plan resources and policies for the management and prevention of flexor tendon injuries.

An Exploratory Study Using Semi-Tabular Plate in Zone II Flexor Tendon Repair.

BACKGROUND: This study evaluated the feasibility of using a low-profile titanium (Ti) plate implant, also known as the Ti-button, for Zone II flexor tendon repair. We hypothesize that the use of the Ti-button can distribute the tensile force on the digital flexor tendons to achieve better biomechanical performance. METHODS: Twenty lacerated porcine flexor tendons were randomly divided into two groups and repaired using Ti-button or 6-strand modified Lim-Tsai technique. Ultimate tensile strength, load to 2 mm gap force, and mode of failure were recorded during a single cycle loading test. We also harvested twelve fingers with lacerated flexor digitorum profundus tendons from six fresh-frozen cadaver hands and repaired the tendons using either Ti-button method or modified Lim-Tsai technique. A custom-made bio-friction measurement jig was used to measure the gliding resistance and coefficient of friction of the tendon sheath interface at the A2 pulley. RESULTS: The ultimate tensile strength, load to 2 mm gap force, stiffness, and gliding resistance of the Ti-button repairs were 101.5 N, 25.7 N, 7.8 N/mm, and 2.2 N respectively. Ti-button repairs had significantly higher ultimate tensile strength and stiffness than the modified Lim-Tsai repair. However, Ti-button also increased the gliding resistance and coefficient of friction but there was no significant difference between the two repair techniques. CONCLUSIONS: Ti-button repair displayed comparable mechanical properties to the traditional repair in terms of 2-mm gap formation and gliding resistance, but with a stronger repair construct. Thus, this deepened our interest to further investigate the potential of using Ti-button implant in Zone II flexor tendon repair by studying both the mechanical and biochemical (tendon healing) properties in more in-depth.

Biomechanical comparison of modified Lim/Tsai tendon repairs with intra- and extra-tendinous knots.

We compared the Lim/Tsai tendon repair technique using an extra-tendinous knot with modification using an intra-tendinous knot. The ultimate tensile strength, load to 2 mm gap force, stiffness, mode of failure, location of failure, and time taken to repair each tendon were recorded during a single cycle loading test in 20 tendons with each repair method. We found that the ultimate tensile strength and 2 mm gap force of the modified Lim/Tsai repair with an extra-tendinous knot (56 SD 5 N and 14 SD 2 N, respectively) were statistically significantly higher than that of the modified Lim/Tsai repair with intra-tendinous knot (51 SD 7 N and 11 SD 2 N, respectively). We conclude that the modified Lim/Tsai repair with extra-tendinous knot is stronger, despite having the same number of core strands.

Biomechanical comparison of the Lim/Tsai tendon repair with a modified method using a single looped suture.

The Lim/Tsai tendon repair technique has been modified clinically to achieve a 6-strand repair using a single looped suture with one extratendinous knot. We compared biomechanical performance of the original and modified methods using 20 porcine flexor digitorum profundus tendons. The ultimate tensile strength, load to 2 mm gap force, mode of failure, and time taken to repair each tendon were recorded during a single cycle loading test in 10 tendons with each repair method. We found that despite having the same number of core strands, the single looped suture modified Lim/Tsai technique possessed significantly greater ultimate tensile strength and load to 2 mm gap force. Also, less repair time was required. We conclude that the modified 6-strand repair using a single looped suture has better mechanical performance than the original method. The difference likely was due to the changes in locations of the knots and subsequent load distribution during tendon loading.