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The clinical assessment of patients with peripheral nerve injury is primarily dependent on subjective clinical examination. We aimed to assess whether a thermotropic liquid crystal ring (TLC-ring) could provide the basis for an objective assessment of peripheral nerve injury by detecting temperature changes in the digits innervated by the damaged nerve.

A group of patients with known median, ulnar or both digital nerve injuries were compared against a control group. TLC-rings, marketed to the general public as "mood rings", were applied to the affected and unaffected digits and the colour change recorded.

Areas with nerve damage showed a statistically significant difference in colour response to those without damage.

This study establishes the ability of TLCs to detect cutaneous temperature changes associated with peripheral nerve injuries. Further studies and improvements are needed to refine TLC as an acute assessment tool for peripheral nerve injuries.

Background: Our aims were to identify iatrogenous injuries to the palmar branch of the median nerve sustained during volar plate fixation of the distal radius, make the clinician aware of this relatively uncommon complication of distal radius fixation, to emphasise common threads in symptomatology and to propose an algorithm for evaluation and management.

Methods: Retrospectively interrogating our database over a 5 year period, the case records, neurophysiology records, operative records, therapy records were reviewed. The data was analysed with regard to the grade of surgeon performing the procedure, the site of injury, complexity of the fracture, delay to surgery, implant choice and outcome of the treatment. Variations in nerve anatomy were documented during revision surgery and common themes in symptomatology and clinical presentation were identified.

Results: Seven patients with an iatrogenic injury involving the palmar branch of the median nerve associated with volar plate fixation of the distal radius were assessed. The male: female ratio was 1:6 and the mean age of patients was 47.8 years (33-74 years). The initial operative fixation was undertaken by a consultant orthopaedic surgeon at a mean of 7.8 (1-17) days from injury. The mean time from fracture fixation surgery to referral to the peripheral nerve injury service was 8.9 (2-36) months. Six patients presented with pain on attempted wrist extension. Five patients had parasthesia, hyperaesthesia or dysaesthesia in the distribution of the PCBMN. Anaesthesia or hypoaesthesia was present in three patients. Two patients presented with symptoms of complex regional pain syndrome (CRPS) Type 2.

Conclusions: Revising relevant anatomy and possible variations as well as careful placements of retractors in the region of the median nerve could bring down these injuries. We propose an algorithm for their management.

A 43-year-old female is presented who underwent a two-stage tendon reconstruction and developed a low ulnar nerve palsy postoperatively. Exploration found that the tendon graft was passing through Guyon’s canal and that the ulnar nerve was divided. This is a previously unreported complication. The reconstruction is discussed, the literature reviewed and a guide is given on how to identify the correct tissue plane when passing a tendon rod.

Background: Motor branch of the ulnar nerve (MUN) injury during carpal tunnel surgery is rare and it should never be injured during carpal tunnel release (CTR). However, an iatrogenic injury of the MUN can cause catastrophic physical and mental suffering. The aim of our study is to understand the anatomy of the MUN in relation to carpal tunnel in order to prevent iatrogenic injury during CTR.

Methods: We dissected 34 fresh cadaver hands and located the MUN in relation to the anatomical axis used for carpal tunnel surgery. Possible mechanisms of injury and the vulnerable area of the MUN were determined along the dissection.

Results: The MUN turned towards the thumb distal to hook of hamate. It then travelled on the floor of the carpal tunnel which was formed by intrinsic hand muscles under flexor tendons. The nerve located at 29.39 ± 7.41, 35.01 ± 3.14 and 38.79 ± 4.03 mm (Mean ± SD) in the central axis of ring finger, the vertical axis of the third web-space and the central axis of middle finger respectively. The nerve’s turning point, 10.9 ± 2.63 mm distal to the centre of hook of hamate where it lies just below the level of the transverse carpal ligament.

Conclusions: Surgeons should be aware of the nerve’s location. Surgical dissection or passing of any surgical instruments around the hook of hamate should be done with care.

Level of Evidence: Level IV (Therapeutic)

Background: Ulnar neuropathy after a distal radius fracture is rare and has limited reports in literature. As such, there is no consensus regarding the optimal treatment and management of such injuries. We report our experience with managing these uncommon injuries.

Methods: A retrospective review was conducted where patients presenting with ulnar neuropathy after sustaining a distal radius fracture were identified from January 2021 to December 2023 from our hospital database.

Results: A total of four patients were identified. All of them underwent surgical fixation for their respective fractures. None of them underwent immediate or delayed exploration and decompression of the ulnar nerve. All patients had clinical improvement at 3 months after their initial injuries. Three patients eventually had resolution of the neuropathy between 5 and 9 months post injury, while one had partial recovery and developed a neuroma but declined surgery due to symptoms minimally affecting work and daily activities.

Conclusions: Ulnar neuropathy after distal radius fractures may not be as rare as previously thought. Expectant management of the neuropathy would be a reasonable treatment as long as there is no evidence of nerve discontinuity or translocation and that there is clinical and/or electrodiagnostic improvement at 3–4 months after the initial injury.

Level of Evidence: Level IV (Therapeutic)

Background: Advances in treatment philosophies and microsurgical techniques for peripheral nerve injuries (PNI) have led to improved outcomes. However, lack of standardisation in the evaluation of clinical outcomes after PNI treatment precludes the ability to compare reconstruction methods, such as nerve transfer, nerve grafting, free functioning muscle transfers and tendon transfers. To this end, our goal is to work collaboratively to establish a core outcome set to evaluate outcomes after PNI.

Methods: The protocol for this arc of work, delineated in this manuscript, consists of two phases: (1) conducting a systematic review of how outcomes are currently reported following PNI and (2) a Delphi process to gain consensus on the measures to include in the core outcome set for PNI. In the Delphi process, two online rounds will be used to gather consensus on the importance of each outcome measure. A final round will be conducted in person to discuss and resolve measures for which there is not yet consensus and to finalise the core outcomes set.

Conclusions: Through this process, a common standard for reporting outcomes after PNI will be created, facilitating collaboration and future research.

Background: Surgeons use anatomical landmarks like the scaphoid tubercle, pisiform, trapezial tubercle and hook of hamate, along with Kaplan cardinal line (KCL) to avoid injury to the recurrent motor branch (RMB) of the median nerve during carpal tunnel release. The presence of transverse muscle fibres (TMF) overlying the transverse carpal ligament (TCL) may suggest proximity of the RMB, but their anatomical relationship is unclear. In this study, we evaluated the accuracy of anatomical landmarks to the RMB, TMF origin and insertion, and examined the relationship between TMF presence and RMB running patterns.

Methods: We dissected 30 hands from 16 fresh-frozen cadavers. After marking the superficial landmarks, we made a skin incision to confirm the presence of TMF and examined their origins and insertions. We then opened the carpal tunnel, dissected the RMB and recorded each position on a coordinate system using a fluoroscopic imaging system.

Results: TMF were observed in 18 hands (60%): 13 were continuous with the abductor pollicis brevis (APB), 2 were continuous with the superficial head of the flexor pollicis brevis (FPB) and 3 were continuous with both. The bifurcation point of the RMB was significantly located 4.5 mm ulnar and 7.5 mm proximal to the superficial landmark at the median. The RMB was classified according to Poisel classification: 24 (80%) were of the extraligamentous type, 4 (13%) of the transligamentous type, 1 (3%) of the preligamentous type and 1 (3%) of the subligamentous type. Amongst these, the transligamentous/preligamentous/subligamentous types are at high risk for RMB injury during TCL incision. No significant association existed between TMF presence and these high-risk RMB types..

Conclusions: The actual RMB may be located ulnar and proximal to the superficial landmark, indicating that surgeons should be cautious about RMB damage even in the absence of TMF.

This research evaluated the use of proteins associated with neurite outgrowth, synapse formation, and Schwann cell proliferation as surrogate measures for morphological measurement of rat sciatic nerve regeneration across a 10-mm gap in silicone rubber conduits (SRCs), genipin-crosslinked gelatin conduits (GGCs), and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS)-crosslinked gelatin conduits (ENGs). After eight weeks, axonal growth of regenerated nerves was determined using light microscopy and computer-based quantitative image analysis. Expression of the axonal growth-associated protein 43 (GAP-43), the synaptic protein synapsin I, and the transforming growth factors type β (TGF-βs) in regenerated nerves was assessed simultaneously by Western blot. As a result, the nerve regenerates in the SRCs and the ENGs had a significantly larger endoneurial area containing more myelinated axons compared to those in the GGCs at p < 0.05. The levels of GAP-43 and synapsin I, but not TGF-β, correlated well with axonal growth in the regenerated nerves. These data suggest that the combined techniques can be used to assess the status of regenerating axons in bridging conduits with different construction and physical properties.