Biochemical and Histological Differences between Longitudinal and Vertical Fibres of Dupuytren's Palmar Aponeurosis and Innovative Clinical Implications.

Dupuytren's disease, a chronic and progressive fibroproliferative lesion of the hand, which affects the palmar fascia, has a recurrence rate after selective aponeurotomy of 20-40% at 5 years. This study focused, for the first time, on the microanatomical and histopathological characteristics of the longitudinal and vertical fibres (usually spared during surgery) in the aponeurosis with Dupuytren's disease, in different stages of the Tubiana's classification. Twelve human samples were collected and analysed by immunostaining, Total Collagen Assay, ELISA Immunoassay, and immunoblotting for the Von Willebrand factor, α-Sma, D2-40, CD-68, Total Collagen, Collagen-I and III, IL1ß, TNF-α to analyse the blood and lymphatic vascularization, the amount and distribution of collagen, and the inflammation. The results show a progressive increase in the arterial vascularization in the vertical fibres (from 8.8/mm2 in the early stage to 21.4/mm2 in stage 3/4), and a parallel progressive decrease in the lymphatic drainage (from 6.2/mm2 to 2.8/mm2), correlated with a local inflammatory context (increase in IL-1ß and TNF-α until the stage 2) in both the longitudinal and vertical fibres. The acute inflammation after stage 2 decreased, in favour of a fibrotic action, with the clear synthesis of new collagen (up to ~83 µg/mg), especially Collagen-I. These results clearly demonstrate the involvement of the septa of Legueu and Juvara in the disease pathology and the modifications with the disease's progression. A greater understanding of the pathology becomes fundamental for staging and the adequate therapeutic timing, to obtain the best morpho-functional result and the lowest risk of complications.

The multiple strategies adopted in a complex case of calcium extravasation in a child: a case report.

Extravasation of calcium solution is a common adverse event in children in intensive care units. The lack of adequate and timely treatment can lead to important functional sequelae. Here, we report the case of calcium extravasation in a child and we discuss the multiple therapeutic strategies adopted.

Ortho-oncoplastic surgery in foot and ankle: A narrative overview on reconstruction of soft-tissue defects after oncologic resections.

INTRODUCTION: Malignant tumors of the foot are rare, and treatment strategies are challenging considering the complex anatomy of this area. In recent years, dramatic advances in technology and collaborations between different specialties (such as orthopedic, oncology, radiology, plastic, and vascular surgery) significantly changed the approach to complex malignant tumors without resorting to limb removal. The combination of the strengths of both orthopedic surgery and plastic surgery constitutes the modern definition of "orthoplasty." The aim of this review article is to provide treatment strategies that are available for reconstruction of foot and ankle in limb-salvage surgery after tumor resection, with a specific focus on microsurgical techniques in plastic surgery. METHODS: We conducted a comprehensive search for relevant papers across PubMed, Scopus, Embase, and Web of Science. We included patient-based studies reporting on procedures for soft-tissue reconstruction with small and large soft tissue defects. Indications, pros and cons, and technique tips are discussed for each type of reconstructive technique. RESULTS: The search was done using literature of the past 30 years (from 1990 to date), resulting in about 725 articles describing over 2000 cases. Cutaneous flaps included lateral supramalleolar flap, medial plantar flap, reverse sural neurocutaneous island flap, medial leg flap, and lateral leg flap. Free flaps included anterolateral thigh flap, radial forearm flap, latissimus dorsi flap, gracilis muscle flap, lateral arm flap, and rectus abdominis flap. CONCLUSIONS: The orthoplastic approach in musculoskeletal oncology is a collaborative model of orthopedic and plastic surgeons working together, resulting in a higher rate of successful limb salvage in patients at risk for amputation. Protocols, biologic substitutes, and surgical techniques are largely improved in the last decades increasing the possibility of functional reconstruction. Microsurgical strategies represent the new frontiers in these demanding reconstructions.

Evaluating Arterialized Vein in Thumb Replantation using Indocyanine Green Angiography: A Case Report.

BACKGROUND The absence of valid vessels for the anastomosis constitutes a contraindication to replantation, but the need for arterial vessels in good condition has recently been questioned and some authors have proposed the arterialization of the veins with promising results. However, this method is not routine in replantation and it is unclear what conditions can establish venous congestion and loss of the replanted segment. CASE REPORT We detail a case where indocyanine green aids in evaluating arterialization of a vein during thumb replantation in a 40-year-old smoker following a crush injury. Multiple attempts to anastomose the princeps pollicis and its collateral vessel failed due to a thrombus formation, leaving the finger non-perfused despite urokinase treatment. To confirm the absence of reperfusion, we administered 0.3 mg/kg of indocyanine green through an upper limb peripheral vein. Observing no reperfusion, we located a suitable radial dorsal vein and performed an arteriovenous anastomosis at the proximal phalanx level. Indocyanine Green Angiography (IGA) revealed a slightly delayed reperfusion but a effective venous outflow. We did not consider it necessary to perform additional venous anastomoses other than the single dorsal radial venous anastomosis. CONCLUSIONS This single case report shows the potential of indocyanine green as a valid aid to evaluate the perfusion of the replantation and also any early venous congestion, being able to modify the operative plan accordingly.

The profunda artery perforators: Anatomical study and radiological findings using computed tomography angiography in patients undergoing PAP flap breast reconstruction.

BACKGROUND: The popularity of the profunda femoris artery perforator (PAP) flap is increasing; however, knowledge concerning the standardization of radiological findings and their clinical implications is limited. We evaluated the radiological architecture of posterior thigh perforators using Computed Tomography Angiography (CTA) to identify landmarks to facilitate flap dissection. METHODS: A retrospective study was conducted on 35 patients who underwent unilateral breast reconstruction with a PAP flap. The preoperative CTA scans were analyzed, and the perforator characteristics were evaluated. The perforators were mapped using a Cartesian coordinate system. Data were normalized by anatomical landmarks and overlapped. Perioperative and postoperative results were analyzed. Radiological and intraoperative were compared. RESULTS: Two CTA scans were excluded; 66 thighs were examined. The mean perforator number was 3.2. The mean diameter of chosen perforators was 2.7 mm (DS ± 0.6 mm) at the origin, 2.2 mm (DS ± 0.4 mm) at the adductor space midpoint, and 1.7 mm (DS ± 0.3 mm) at the deep fascia. The mean adipose tissue thickness was 3.35 cm (DS ± 0.94) at the deep fascia and 3.59 cm (DS ± 1.19) at the adductor space midpoint. Intraoperatively, the perforator was located 3.22 cm (DS ± 0.87) from the posterior border of the gracilis muscle and 8.98 cm (DS ± 1.44) from the inferior gluteal crease. A radiological area located 9.33 cm (DS ± 4.81) from the y-axis and 7.48 cm (DS ± 1.88) from the x-axis was identified. CONCLUSIONS: CTA using the volume-rendering technique is a valuable method to study in vivo the radiological anatomy of the posterior thigh perforators.

Efficacy and safety of Dynavisc® gel in prevention of scar adhesions recurrence after flexor tendons tenolysis in zone 2. Multicenter retrospective cohort study.

AIM: Dynavisc® is a novel surgical product made of carboxymethylcellulose (CMC) and Polyethylene Oxide (PEO) designed to reduce post-surgical adhesions in tendons surgery. A multicenter retrospective cohort study was performed to investigate the clinical safety and efficacy of the Dynavisc® gel in reducing post-surgical adhesions after flexor tenolysis in zone 2. MATERIAL OF STUDY: Thirty-one patients suffering from stiff finger after flexor tendon repairs in zone 2 treated with standard release with (18 Dynavisc®-treated group) or without (13 controls) anti-adhesion gel application into the flexor tendon sheath and around the site of the tenolysis, were collected in five different hand surgery units. Safety profile and functional outcomes (based on TAM test and the The Quick-DASH questionnaire) were examined from patients' charts and analyzed. RESULTS: The application of Dynavisc® posed no safety concerns and it was not related to any additional complication. The Dynavisc®-treated group showed greater progressive improvement of TAM value in all visits with superior TAM value at T(90) and T(180) compared to the control group. DISCUSSION: Tendon adhesions are the main cause of flexor tendon surgery failure. Multiple strategies (i.e. robust tendon repair, early rehabilitation and lubricant or barrier agents) have been proposed to minimize their formation. Among different products described in the literature Dynavisc® showed a significant role in limiting adhesions formation in a recent experimental study. CONCLUSIONS: This clinical study confirm the safety of Dynavisc® gel application in hand surgery demonstrating its potential long-term benefits after flexor tendon tenolysis. KEY WORDS: Flexor Tendon Repair, Tendon Adhesions, Tenolysis.

Development and preclinical evaluation of bioactive nerve conduits for peripheral nerve regeneration: A comparative study.

In severe peripheral nerve injuries, nerve conduits (NCs) are good alternatives to autografts/allografts; however, the results the available devices guarantee for are still not fully satisfactory. Herein, differently bioactivated NCs based on the new polymer oxidized polyvinyl alcohol (OxPVA) are compared in a rat model of sciatic nerve neurotmesis (gap: 5 mm; end point: 6 weeks). Thirty Sprague Dawley rats are randomized to 6 groups: Reverse Autograft (RA); Reaxon®; OxPVA; OxPVA + EAK (self-assembling peptide, mechanical incorporation); OxPVA + EAK-YIGSR (mechanical incorporation); OxPVA + Nerve Growth Factor (NGF) (adsorption). Preliminarily, all OxPVA-based devices are comparable with Reaxon® in Sciatic Functional Index score and gait analysis; moreover, all conduits sustain nerve regeneration (S100, ß-tubulin) without showing substantial inflammation (CD3, F4/80) evidences. Following morphometric analyses, OxPVA confirms its potential in PNI repair (comparable with Reaxon®) whereas OxPVA + EAK-YIGSR stands out for its myelinated axons total number and density, revealing promising in injury recovery and for future application in clinical practice.

Detection of Mast Cells in Human Superficial Fascia.

The recent findings showed that the superficial fascia is a fibrous layer in the middle of hypodermis, richly innervated and vascularized, and more complex than so far demonstrated. This study showed the presence of mast cells in the superficial fascia of the human abdomen wall of three adult volunteer patients (mean age 42 ± 4 years; 2 females, 1 male), by Toluidine Blue and Safranin-O stains and Transmission Electron Microscopy. Mast cells are distributed among the collagen bundles and the elastic fibers, near the vessels and close to the nerves supplying the tissue, with an average density of 20.4 ± 9.4/mm2. The demonstration of the presence of mast cells in the human superficial fascia highlights the possible involvement of the tissue in the inflammatory process, and in tissue healing and regeneration processes. A clear knowledge of this anatomical structure of the hypodermis is fundamental for a good comprehension of some fascial dysfunctions and for a better-targeted clinical practice.

Bridging Gaps in Peripheral Nerves: From Current Strategies to Future Perspectives in Conduit Design.

In peripheral nerve injuries (PNI) with substance loss, where tensionless end-to-end suture is not achievable, the positioning of a graft is required. Available options include autografts (e.g., sural nerve, medial and lateral antebrachial cutaneous nerves, superficial branch of the radial nerve), allografts (Avance®; human origin), and hollow nerve conduits. There are eleven commercial hollow conduits approved for clinical, and they consist of devices made of a non-biodegradable synthetic polymer (polyvinyl alcohol), biodegradable synthetic polymers (poly(DL-lactide-ε-caprolactone); polyglycolic acid), and biodegradable natural polymers (collagen type I with/without glycosaminoglycan; chitosan; porcine small intestinal submucosa); different resorption times are available for resorbable guides, ranging from three months to four years. Unfortunately, anatomical/functional nerve regeneration requirements are not satisfied by any of the possible alternatives; to date, focusing on wall and/or inner lumen organization/functionalization seems to be the most promising strategy for next-generation device fabrication. Porous or grooved walls as well as multichannel lumens and luminal fillers are the most intriguing options, eventually also including the addition of cells (Schwann cells, bone marrow-derived, and adipose tissue derived stem cells) to support nerve regeneration. This review aims to describe common alternatives for severe PNI recovery with a highlight of future conduits.

Detection of Lymphatic Vessels in the Superficial Fascia of the Abdomen.

Recently, the superficial fascia has been recognized as a specific anatomical structure between the two adipose layers-the superficial adipose tissue (SAT) and the deep adipose tissue (DAT). The evaluation of specific characteristics of cells, fibers, blood circulation, and innervation has shown that the superficial fascia has a clear and distinct anatomical identity, but knowledge about lymphatic vessels in relation to the superficial fascia has not been described. The aim of this study was to evaluate the presence of lymphatic vessels in the hypodermis, with a specific focus on the superficial fascia and in relation to the layered subdivision of the subcutaneous tissue into SAT and DAT. Tissue specimens were harvested from three adult volunteer patients during abdominoplasty and stained with D2-40 antibody for the lymphatic endothelium. In the papillary dermis, a huge presence of lymphatic vessels was highlighted, parallel to the skin surface and embedded in the loose connective tissue. In the superficial adipose tissue, thin lymphatic vessels (mean diameter of 11.6 ± 7.71 µm) were found, close to the fibrous septa connecting the dermis to the deeper layers. The deep adipose tissue showed a comparable overall content of lymphatic vessels with respect to the superficial layer; they followed the blood vessel and had a larger diameter. In the superficial fascia, the lymphatic vessels showed higher density and a larger diameter, in both the longitudinal and transverse directions along the fibers, as well as vessels that intertwined with one another, forming a rich network of vessels. This study demonstrated a different distribution of the lymphatic vessels in the various subcutaneous layers, especially in the superficial fascia, and the demonstration of the variable gauge of the vessels leads us to believe that they play different functional roles in the collection and transport of interstitial fluid-important factors in various surgical and rehabilitation fields.

Topography of the deep branch of the ulnar nerve between genders: a cadaveric study with potential clinical implications.

The lack of meticulous knowledge concerning the topographical anatomy of the deep branch of the ulnar nerve (DUN) may pose difficulties, leading to a delay or a misdiagnosis of a DUN injury. Identification of the DUN is quite difficult without precise anatomical landmarks as reference points. The current study investigates the topography of the DUN between genders, taking as a reference point a well-known landmark, the Kaplan line, used in hand surgery for carpal tunnel release. Twenty-two (15 males and 7 female) fresh frozen adult cadaveric hands were dissected by using magnifying loupes (3.5 and 5.0 x). We marked values proximal to the Kaplan line as positive (+), while we marked distal ones as negative (-). The mean distance DUN-Kaplan line was 1.69 ± 4.45 mm. In male hands, the mean distance was 4.17 ± 1.88 mm, distal to the Kaplan line, while in females, the mean distance was -4.92 ± 0.69 mm proximal to the Kaplan line. Gender dimorphism was detected, with higher statistically significant values in male hands (p = 0.001). Cadaveric studies of the DUN topography, course, and distribution pattern are uncommon. The current study provides an accurate description of the DUN topography, taking the Kaplan line as a reference point, emphasizing gender differences. The DUN is located distally in males and proximally in females. Knowledge of these predictable anatomical relations may help hand surgeons intraoperatively when dealing with a DUN lesion, because of hand trauma or during the decompression of the DUN.

Blood supply to the superficial fascia of the abdomen: An anatomical study.

The aim of this study was to examine data demonstrating that Scarpa's fascia, a superficial fascia of the anterior abdominal wall, is a vascularized tissue. Specimens of the fascia of seven volunteers undergoing abdominoplasty surgical procedures at the Plastic Surgery Unit of the University of Padova Medical Center were collected. Fractal analysis and quantitative assessment of the vascular network of the fascia was carried out, exploiting the presence of blood in the vessels. Each sample was divided and processed for histological/immunohistochemical analysis (into 5 micron-paraffin embedded sections and cryo-sectioned free-floating samples) as well as for electron microscopy study. A rich vascular pattern forming a fine, dense meshwork with an area percentage of 6.20% ± 2.10% von Willebrand factor stained vessels was noted in all the specimens of the fascia examined; the area percentage of the αSMA-stained vessels was 2.93% ± 1.80%. The diameters of the vessels fell between the 13 and 65 µm range; the network was composed of arteries, veins, capillaries and lymphatic segments. Topological results showed that the vascular network within Scarpa's fascia is well branched (segments: 6615 ± 3070 and 8.40 ± 3.40 per mm2 ; crossing points: 3092 ± 1490 and 3.40 ± 1.90 per mm2 ). Fractal analysis (fractal dimension = 1.063 ± 0.10; lacunarity = 0.60 ± 0.10) revealed that this particular vascular network has an optimal spatial distribution and homogeneity occupying the entire space of the superficial fascia. These findings could undoubtedly be useful to plastic surgeons as well as to pain management specialists.

The origins of the camper's chiasm asymmetry: a cadaveric study and clinical implications for flexor tendons surgery.

The Camper's chiasm (CC) originates from the decussation of tendon fibers of the flexor digitorum superficialis at the level of the proximal phalanx. Previous studies described several conformations of the CC, but none has studied the asymmetry pattern for each finger. We lack studies about the relationship between the vincula tendinum and the morphology of the CC. We aimed to study the precise pattern of asymmetry and the aforementioned relationship in a cadaveric study. We studied the fingers of 9 fresh frozen human hands (thumb excluded). We observed the distribution of the fibers and categorized each CC according to the Gonzalez classification. Finally, we recorded the inset point of the vincula longa superficiales (VLS) according to Schmidt. We found 7 symmetrical CCs, while the remaining 29 showed an asymmetrical pattern that matched with the site of insertion of the VLS. For the index and long fingers, we detected a dominance of the ulnar slip. For the ring and little finger, we found a higher radial dominance. The inset point of the VLS always coincided with the side of slip dominance, whereas in symmetrical CCs, the VLS was symmetrical as well. Since the vascular role of the vincula tendinum, we speculate that the asymmetry of the CC may be of vascular origin.

Reverse posterior interosseous flap: different approaches over the years - A systematic review.

The posterior interosseous flap (PIOF), as fasciocutaneous flap, represents an interesting option in reconstructive surgery of the upper limb. The PIOF allows coverage of losses of substance of the dorsal side of the hand and, with technical modifications, up to the proximal interphalangeal (PIP) joint without any need of microsurgical technique or the sacrifice of the main vascular axes for the hand. Its dimensions can reach up to 22 cm x12 cm and have excellent versatility since it can incorporate vascularized bone grafts and tendon grafts for complex substance losses. Despite the above-mentioned advantages, among the factors that limit its diffusion, indeed, there is the complex dissection technique originally described. Several authors also report a variable incidence of venous congestion, attributing it to the reverse flow vascularity of the flap. However, in the hands of experienced surgeons, this flap has a negligible incidence of complications. For these reasons, the authors performed a systematic review of the literature to organize the various technical updates over the years to extend the indications of the PIOF and reduce the incidence of complications, thus providing a valuable tool for reconstructive surgeons.

Innervation of human superficial fascia.

The superficial fascia has only recently been recognized as a specific anatomical structure. Furthermore, whereas it is actually recognized that the innervation of the deep/muscular fascia plays a key role in proprioception and nociception, there are very few studies that have analyzed these characteristics in the superficial fascia. In this work, our group analyzed two different anatomical districts (abdomen and thigh), from volunteer patients, undergoing surgery procedures. Each sample was processed for histological analysis by Hematoxylin&Eosin, and by immunohistochemistry stainings (in 5-micron-paraffin embedded section and in cryosectioned free floating samples), with antibodies specific for nerve fibers: S100 antibody for myelinating and non-myelinating Schwann cells, PGP9.5 antibody as pan-neuronal marker, tyrosine hydroxylase for autonomic innervation. The results revealed a huge innervation: the nervous structures were found above all around blood vessels and close to adipocytes, but they penetrated also in the connective tissue itself and are found in the midst of fibro-adipose tissue. The tissue is pervaded by both thin (mean diameter of 4.8 ± 2.6 µm) and large nerve fiber bundles of greater diameter (21.1 ± 12.2 µm). The ratio S100/TH positivity was equal to 2.96, with a relative percentage of autonomic innervation with of 33.82%. In the light of these findings is evident that the superficial fasciae have a clear and distinct anatomical identity and a specific innervation, which should be considered to better understand their role in thermoregulation, exteroception and pain perception. The knowledge of the superficial fascia may improve grading and developing of different manual approach for treatments of fascial dysfunctions, and the understanding of how some factors like temperature or manual therapies can have an impact on sensitivity of the fascia.

Deep inferior epigastric perforator flap preoperative planning: A comparative analysis between dynamic infrared thermography, computerized tomography angiography, and hand-held Doppler.

INTRODUCTION: Hand-held Doppler (HHD) sonography and computerized tomography angiography (CTA) are the common assessment tools for deep inferior epigastric perforator (DIEP) flap preoperative planning. CTA is considered the gold standard method for preoperative perforator mapping but necessitates contrast medium and X-ray exposure. Dynamic infrared thermography (DIRT) does not have these drawbacks and allows the detection of hot and cold spots on a given body area. Our study aimed to compare DIRT, HHD, and CTA in perforator mapping for breast reconstruction using DIEP flap. PATIENTS AND METHODS: From March to September 2020, 12 consecutive patients scheduled for DIEP flap breast reconstruction were preoperatively investigated with HHD, CTA, and DIRT. The patients' mean age was 53 and the mean BMI was 29.23 kg/m2 . All the reconstructions were due to breast cancer. The results of preoperative perforator mapping on the lower abdomen were compared among the three techniques. All the evidence was compared to the intraoperative findings, during flap harvesting, to establish if the techniques were able to correctly locate the perforator. RESULTS: We detected 178 perforators intraoperatively, 178 with CTA, 178 with DIRT, and 125 with HHD. The latter revealed a lower number of perforator vessels for each patient (10.42 ± 3.58), compared with CTA (14.83 ± 3.04) and DIRT (14.83 ± 4.76). DIRT resulted superior to HHD (p < .05), while no statistically significant difference (p > .05) was found between DIRT and CTA. We calculated a mean sensitivity of 93.87% for CTA, 69.02% for HHD, and 92.06% for DIRT. CONCLUSION: DIRT is a useful tool in the preoperative planning of DIEP flaps, as it provides information about the location of perforators and the hemodynamic properties of angiosomes. It is easy to use, and it does not involve ionizing radiation. DIRT could represent an innovative and promising implementation of CTA and HHD techniques for preoperative perforator mapping in DIEP breast reconstruction.

Lumbrical Muscles Neural Branching Patterns: A Cadaveric Study With Potential Clinical Implications.

BACKGROUND: Lumbrical muscles originate in the palm from the 4 tendons of the flexor digitorum profundus and course distally along the radial side of the corresponding metacarpophalangeal joints, in front of the deep transverse metacarpal ligament. The first and second lumbrical muscles are typically innervated by the median nerve, and third and fourth by the ulnar nerve. A plethora of lumbrical muscle variants has been described, ranging from muscles' absence to reduction in their number or presence of accessory slips. The current cadaveric study highlights typical and variable neural supply of lumbrical muscles. MATERIALS: Eight (3 right and 5 left) fresh frozen cadaveric hands of 3 males and 5 females of unknown age were dissected. From the palmar wrist crease, the median and ulnar nerve followed distally to their terminal branches. The ulnar nerve deep branch was dissected and lumbrical muscle innervation patterns were noted. RESULTS: The frequency of typical innervations of lumbrical muscles is confirmed. The second lumbrical nerve had a double composition from both the median and ulnar nerves, in 12.5% of the hands. The thickest branch (1.38 mm) originated from the ulnar nerve and supplied the third lumbrical muscle, and the thinnest one (0.67 mm) from the ulnar nerve and supplied the fourth lumbrical muscle. In 54.5%, lumbrical nerve bifurcation was identified. CONCLUSION: The complex innervation pattern and the peculiar anatomy of branching to different thirds of the muscle bellies are pointed out. These findings are important in dealing with complex and deep injuries in the palmar region, including transmetacarpal amputations.

Combining traditional and microsurgical reconstruction after a complex hand trauma with multiple tissue defects. A case report.

Complex injuries involving bones, tendons and soft tissues of the hand still represent a difficult challenge for reconstructive surgeons. Hereby, we present a case of a man suffering from a complex crush injury of the right hand that led to a wide three-dimensional defect with loss of two metacarpal bones, extensor tendons and skin. For composite hand defects, the most common surgical approach provides for a one-stage composite reconstruction or for an early restoration of bone and skin, with delayed tendon grafts. For the peculiarity of the defect, a one-stage reconstruction was not feasible. Hence, we opted for a two-stage reconstruction but the usual surgical steps have been inverted. First we secured tendon and skin restoration through a composite teno-cutaneous radial free flap. A month later, we reconstructed the two metacarpals with a modified Masquelet technique using fibular cortical graft. This strategy allowed the patient to start an early rehabilitation program and obtain a satisfactory recovery of his dominant hand. KEY WORDS: Composite flap, Hand trauma, Hand reconstruction, Microsurgery.

Studying nerve transfers: Searching for a consensus in nerve axons count.

Axonal count is the base for efficient nerve transfer; despite its capital importance, few studies have been published on human material, most research approaches being performed on experimental animal models of nerve injury. Thus, standard analysis methods are still lacking. Quantitative data obtained have to be reproducible and comparable with published data by other research groups. To share results with the scientific community, the standardization of quantitative analysis is a fundamental step. For this purpose, the experiences of the Italian, Austrian, German, Greek, and Iberian-Latin American groups have been compared with each other and with the existing literature to reach a consensus in the fiber count and draw up a protocol that can make future studies from different centers comparable. The search for a standardization of the methodology was aimed to reduce all the factors that are associated with an increase in the variability of the results. All the preferential methods to be used have been suggested. On the other hand, alternative methods and different methods have been identified to achieve the same goal, which in our experience are completely comparable; therefore, they can be used indifferently by the different centers according to their experience and availability.