Update on Upper Limb Neuroma Management.

Painful terminal neuromas in the upper limb due to nerve injury are common. Neuroma symptoms include a sharp and burning sensation, cold intolerance, dysesthesia, pain, numbness, and paresthesia. These symptoms could have a negative impact on the functional ability of the patient and quality of life. In addition, Prostheses use might be abandoned by amputees due to neuroma-induced pain. Many clinicians face challenges while managing neuromas. Contemporary "active" methods like regenerative peripheral nerve interface (RPNI), targeted muscle reinnervation (TMR), and processed nerve allograft repair (PNA) are replacing the conventional "passive" approaches such as excision, transposition, and implantation techniques. RPNI involves inducing axonal sprouting by transplanting the free end of a peripheral nerve into a free muscle graft. TMR includes reassigning the role of the peripheral nerve by the transfer of the distal end of a pure sensory or a mixed peripheral nerve to a motor nerve of a nearby muscle segment. To give the peripheral nerve a pathway to re-innervate its target tissue, PNA entails implanting a sterile extracellular matrix prepared from decellularized and regenerated human nerve tissue with preserved epineurium and fascicles. Of these, RPNI and TMR appear to hold a promising treatment for nerve-ending neuromas and prevent their relapse. In contrast, PNA may reduce neuroma pain and allow meaningful nerve repair. The aim of this article is to provide an overview of the newer approaches of TMR, RPNI, and PNA and discuss their implications, surgical techniques, and reported consequences.

Nerve transfers in the forearm: potential use in spastic conditions.

PURPOSE: Deformities of the spastic upper limb result frequently from the association of spasticity, muscle contracture and muscle imbalance between strong spastic muscles and weak non-spastic muscles. This study was designed to evaluate the feasibility of combining selective neurectomy of the usual spastic and strong muscles together with transfer of their motor nerves to the usual weak muscles, to improve wrist and fingers motion while decreasing spasticity. METHODS: Twenty upper limbs from fresh frozen human cadavers were dissected. All motor branches of the radial and median nerve for the forearm muscles were identified. We attempted all possible end-to-end nerve transfers between the usually strong "donor" motor branches, namely FCR and PT, and the usually weak "recipient" motor branches (ERCL, ECRB, PIN, AIN). RESULTS:  The PT had two nerve branches in 80%, thus allowing selective neurectomy. The proximal PT branch could be anastomosed end-to-end in 45% (AIN) to 85% (ECRL) of cases with the potential recipient branches. The distal PT branch could be anastomosed end to end to all potential recipient nerves. The FCR had a single branch in all cases. End-to-end anastomosis was possible in 90% for the ECRL and in 100% for all other recipient branches, but sacrificed all FCR innervation, ruling out hyperselective neurectomy. CONCLUSION:  Selective neurectomies can be associated with distal nerve transfers at the forearm level in selected cases. The motor nerve to the PT is the best donor for nerve transfer combined with selective neurectomy, transferred to the ECRL, ECRB, PIN or AIN.

Two-stage free flap reconstruction of the scalp and calvaria for large neurosurgical resections.

BACKGROUND: Free tissue transfer is occasionally necessary during reconstruction of large scalp and calvarial bone resections. A single-stage procedure is usually performed but if a flap becomes necrotic it exposes brain tissue or the meninges. Performing a two-stage procedure, the surgeon must preserve flap vitality and manage flap complications before resecting a tumor, and therefore before exposing the brain or meninges. We report here the first series of two-stage free-flap reconstruction during major neurosurgical resection. METHODS: From 2012 to 2018, nine free-flaps were performed to eight patients (61 years-old, on average). Average skull resection was 10.1 cm × 15 cm (range 6-18 cm × 9-24 cm). It was performed in all cases due to large malignant tumors. Resection/reconstruction was performed in all case in a two-step procedure: during the first step, the free-flap was harvested and anastomosed to the cranial site; during the second step, resection was performed and the flap was positioned into the defect to assure coverage. RESULTS: Average flap size was 11.3 cm × 17.7 cm (range: 7-20 cm × 11-30 cm). Two flap complications occurred after the first stage and one flap did not survive. One patient died before the second stage. Seven patients had the second procedure; no flap complication occurred. All procedures ended in complete wound healing. Follow-up period was 41.5 months on average (range: 10-83 months). Final outcome was total remission for two patients, recurrence for four patients, and two patients died. CONCLUSIONS: Our data suggest that the two-stage free-flap reconstruction may be employed for major scalp and calvaria resection.

Immediate or Delayed Transplantation of a Vein Conduit Filled with Nasal Olfactory Stem Cells Improves Locomotion and Axogenesis in Rats after a Peroneal Nerve Loss of Substance.

Over the recent years, several methods have been experienced to repair injured peripheral nerves. Among investigated strategies, the use of natural or synthetic conduits was validated for clinical application. In this study, we assessed the therapeutic potential of vein guides, transplanted immediately or two weeks after a peroneal nerve injury and filled with olfactory ecto-mesenchymal stem cells (OEMSC). Rats were randomly allocated to five groups. A3 mm peroneal nerve loss was bridged, acutely or chronically, with a 1 cm long femoral vein and with/without OEMSCs. These four groups were compared to unoperated rats (Control group). OEMSCs were purified from male olfactory mucosae and grafted into female hosts. Three months after surgery, nerve repair was analyzed by measuring locomotor function, mechanical muscle properties, muscle mass, axon number, and myelination. We observed that stem cells significantly (i) increased locomotor recovery, (ii) partially maintained the contractile phenotype of the target muscle, and (iii) augmented the number of growing axons. OEMSCs remained in the nerve and did not migrate in other organs. These results open the way for a phase I/IIa clinical trial based on the autologous engraftment of OEMSCs in patients with a nerve injury, especially those with neglected wounds.

Development of Autologous Platelet-Rich Plasma Mixed-Microfat as an Advanced Therapy Medicinal Product for Intra-Articular Injection of Radio-Carpal Osteoarthritis: From Validation Data to Preliminary Clinical Results.

Wrist osteoarthritis (OA) is one of the most common conditions encountered by hand surgeons with limited efficacy of non-surgical treatments. The purpose of this study is to describe the Platelet-Rich Plasma (PRP) mixed-microfat biological characteristics of an experimental Advanced Therapy Medicinal Product (ATMP) needed for clinical trial authorization and describe the clinical results obtained from our first three patients 12 months after treatment (NCT03164122). Biological characterization of microfat, PRP and mixture were analysed in vitro according to validated methods. Patients with stage four OA according to the Kellgren Lawrence classification, with failure to conservative treatment and a persistent daily painful condition >40 mm according to the visual analog scale (VAS) were treated. Microfat-PRP ATMP is a product with high platelet purity, conserved viability of stromal vascular fraction cells, chondrogenic differentiation capacity in vitro and high secretion of IL-1Ra anti-inflammatory cytokine. For patients, the only side effect was pain at the adipose tissue harvesting sites. Potential efficacy was observed with a pain decrease of over 50% (per VAS score) and the achievement of minimal clinically important differences for DASH and PRWE functional scores at one year in all three patients. Microfat-PRP ATMP presented a good safety profile after an injection in wrist OA. Efficacy trials are necessary to assess whether this innovative strategy could delay the necessity to perform non-conservative surgery.

Gastrocnemius Myocutaneous Flaps for Knee Joint Coverage.

INTRODUCTION: The gastrocnemius muscular flap has already proven its efficiency for soft tissue coverage in cases of knee joint exposure. However, it may be too small to cover large defects and has not the same aesthetic and mechanical properties as normal skin. Perforator fasciocutaneous flaps have recently been described in knee joint coverage with good results as they replace skin by skin, but they can be hard to harvest. Gastrocnemius flaps can be easily harvested with a planned skin paddle designed over the chosen muscle. This simple technique combines the advantages of muscular and fasciocutaneous flaps for knee joint area coverage. Perforator fasciocutaneous flap take a growing place in coverage of this localization in recent literature, but very few articles report the results of gastrocnemius myocutaneous flaps (MCFs). METHODS: All patients who underwent knee joint coverage with the use of a lateral or medial gastrocnemius MCFs between January 2012 and February 2017 in our university institution were included in this retrospective study. RESULTS: Sixteen gastrocnemius MCFs (10 medial and 6 lateral) were performed. The indication was posttraumatic in 5 cases, posttumoral in 5 cases, and after total knee prosthesis exposure in 6 cases. Skin paddles up to 15 cm in width and 18 cm in length were harvested. Complete healing was achieved in 15 days in all cases without suffering or nonunion. Three flaps were secondarily raised to allow total knee prosthesis reimplantation or arthrodesis, and 4 patients were treated with postoperative radiotherapy without complication. CONCLUSIONS: In addition to its reliability and very easy harvesting, the gastrocnemius MCF allows a robust joint coverage and good skin resurfacing that makes eventual revision easier and allows early radiotherapy. Furthermore, skin paddle also increases the effective area of the flap. This technique should always be considered with the other classic alternatives.

The temporoparietal fascia flap folded into a ball in the treatment of retroauricular cerebrospinal fluid fistulae after posterior fossa surgery.

BACKGROUND: Skull base and posterior fossa surgeries are sometimes complicated by cerebrospinal fluid (CSF) fistulae, which may be challenging to treat. They can lead to meningitis, increasing global morbidity and mortality. In case of failed medical treatment, revision surgery may be required. "Fat packing" (adipose tissue grafts) is usually used to close the communication between the intracranial contents and the cutaneous tissue, and to fill the dead space created by the skull base surgery. Vascularised flaps can also be used. They seem more efficient, especially in multi-operated patients or after radiotherapy, when cutaneous tissue is adhesive and fragile. METHODS: Temporoparietal fascia (TPF) flap is a regional flap; it has reliable blood supply and can cover temporal and retroauricular defects. Folded into a ball, it can fill small dead spaces and can be skin grafted in case of cutaneous defect. RESULTS AND CONCLUSIONS: We present a simple surgical solution to manage recurrent retroauricular CSF fistulae after posterior fossa surgery using a pedicled TPF flap folded into a ball.

Secondary complications in Wassel II & IV thumb duplication: a comprehensive review of preventive measures.

OBJECTIVES: Thumb duplication is one of the most challenging pediatric reconstructive hand surgeries. Wassel types II and IV are the most frequent, but also the most complex reconstructions as the duplication arises at the joint level. Ablation and reconstruction, the most widely used technique, aims at achieving a stable, well-aligned, mobile and esthetically acceptable thumb. The paucity of reliable surgical guidelines leads to high rates of suboptimal surgical outcomes. This review evaluated the various reconstruction techniques detailed in the literature and highlighted useful methods to prevent common secondary complications. METHODS: A comprehensive PubMed and Embase literature search was made. Inclusion criteria were Wassel type II and/or IV, pediatric patients, and primary or secondary surgeries. Exclusion criteria were Bilhaut-Cloquet reconstruction and its modifications. Techniques were screened, collected and analyzed for the following secondary complications: instability, axial deformity, and contour deformity. RESULTS: Thirty-two articles met the inclusion criteria and were reviewed. Postoperative instability was prevented by tightening the joint capsule by plication, advancement of the volar plate, or reconstruction of the collateral ligaments using a periosteal flap or the double-breasting technique. Axial deformity was prevented by arthroplasty, shaving a triangular portion of the metacarpal head, centralization of eccentric tendons, pulley reconstruction using flexor pollicis longus, or corrective osteotomies of the phalangeal or metacarpal bones using the wedge or oblique techniques. Limited range of motion was prevented by first webspace Z-plasty, and soft-tissue contouring was addressed by planned skin incisions and soft-tissue augmentation. Preoperative, perioperative and postoperative considerations, including splinting, imaging and immobilization, were also described. CONCLUSION: Despite the ongoing advances and abundant knowledge in reconstructive strategies for thumb duplication, there are few studies that reviewed and analyzed the various reported options. This review provides physicians and trainees with guidance in surgical planning to prevent common secondary complications. Further research should focus on the development of standardized assessment tools, enabling reliable prospective comparative studies on thumb duplication reconstruction. LEVEL OF EVIDENCE: IV.

Scaphoid proximal pole ejection in perilunate injury: a case report and pathophysiological hypothesis.

Isolated ejection of the scaphoid proximal pole in perilunate injuries is rare, with only 4 reports in the literature, and does not correspond to the biomechanical situations in the Herzberg or Mayfield classifications. Bone ejection incurs a risk of avascular necrosis despite good osteosynthesis, notably because of precarious vascularization. We present a case of scaphoid proximal pole ejection and a theoretical hypothesis of the biomechanics of this injury. LEVEL OF EVIDENCE: 4.

Biomechanical evaluation of the ST-knot: A new suture for flexor tendon repair.

PURPOSE: Although tendon lacerations are common, there is currently no consensus on choice of suture. Easy and fast sutures that impart enough strength to allow mobilization are needed. This study compared the ex vivo biomechanical strength (force required to create a 2 mm tendon gap) of a novel suture (ST-knot) with that of a conventional suture (double Kessler). MATERIALS AND METHODS: Forty fresh deep flexor tendons from porcine forelimbs were used. Both repaired tendon ends were mounted on standard traction jaws of an axial traction machine at an initial distance of 40 mm for all tendons. A high-definition camera was used to determine the force forming a 2 mm gap. Ten tendons in group 1 (ST-knot) and 10 in group 2 (double Kessler) were prepared with PDS 4.0 (single thread for Kessler, double thread for ST-knot). Tendons in groups 3 (ST-knot) and 4 (double Kessler) were repaired with PDS 1.0 using the same principle. RESULTS: There was no significant difference in the force required to form a 2 mm tendon gap between groups 1 and 2, and this trend was identical when using a stronger thread in groups 3 and 4. The maximum force before rupture, mode of repair failure, stress and stiffness were also comparable, with no significant differences between groups 1 and 2, or between groups 3 and 4. CONCLUSIONS: The ST-knot showed comparable results to the double-Kessler knot, whichever the thread used. Because it involves fewer steps than conventional techniques and is easy to perform, the ST-knot may offer a therapeutic solution, particularly in complex trauma with multiple tendon injury.