Traumatic peripheral nerve injuries: a classification proposal.

BACKGROUND: Peripheral nerve injuries (PNIs) include several conditions in which one or more peripheral nerves are damaged. Trauma is one of the most common causes of PNIs and young people are particularly affected. They have a significant impact on patients' quality of life and on the healthcare system, while timing and type of surgical treatment are of the utmost importance to guarantee the most favorable functional recovery. To date, several different classifications of PNIs have been proposed, most of them focusing on just one or few aspects of these complex conditions, such as type of injury, anatomic situation, or prognostic factors. Current classifications do not enable us to have a complete view of this pathology, which includes diagnosis, treatment choice, and possible outcomes. This fragmentation sometimes leads to an ambiguous definition of PNIs and the impossibility of exchanging crucial information between different physicians and healthcare structures, which can create confusion in the choice of therapeutic strategies and timing of surgery. MATERIALS: The authors retrospectively analyzed a group of 24 patients treated in their center and applied a new classification for PNI injuries. They chose (a) five injury-related factors, namely nerve involved, lesion site, nerve type (whether motor, sensory or mixed), surrounding tissues (whether soft tissues were involved or not), and lesion type-whether partial/in continuity or complete. An alphanumeric code was applied to each of these classes, and (b) four prognostic codes, related to age, timing, techniques, and comorbidities. RESULTS: An alphanumeric code was produced, similar to that used in the AO classification of fractures. CONCLUSIONS: The authors propose this novel classification for PNIs, with the main advantage to allow physicians to easily understand the characteristics of nerve lesions, severity, possibility of spontaneous recovery, onset of early complications, need for surgical treatment, and the best surgical approach. LEVEL OF EVIDENCE: according to the Oxford 2011 level of evidence, level 2.

Mesenchymal Stem Cell Treatment Perspectives in Peripheral Nerve Regeneration: Systematic Review.

Traumatic peripheral nerve lesions affect hundreds of thousands of patients every year; their consequences are life-altering and often devastating and cause alterations in movement and sensitivity. Spontaneous peripheral nerve recovery is often inadequate. In this context, nowadays, cell therapy represents one of the most innovative approaches in the field of nerve repair therapies. The purpose of this systematic review is to discuss the features of different types of mesenchymal stem cells (MSCs) relevant for peripheral nerve regeneration after nerve injury. The published literature was reviewed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A combination of the keywords "nerve regeneration", "stem cells", "peripheral nerve injury", "rat", and "human" were used. Additionally, a "MeSH" research was performed in PubMed using the terms "stem cells" and "nerve regeneration". The characteristics of the most widely used MSCs, their paracrine potential, targeted stimulation, and differentiation potentials into Schwann-like and neuronal-like cells are described in this paper. Considering their ability to support and stimulate axonal growth, their remarkable paracrine activity, their presumed differentiation potential, their extremely low immunogenicity, and their high survival rate after transplantation, ADSCs appear to be the most suitable and promising MSCs for the recovery of peripheral nerve lesion. Clinical considerations are finally reported.

Double cystic brain metastasis in a patient with stable pancreatic intraductal papillary mucinous neoplasm.

BACKGROUND: Brain metastases in pancreatic cancer are a rare condition and are usually seen in case of pancreatic adenocarcinoma. Only few cases of brain metastasis in patients affected by Intraductal papillary mucinous neoplasm (IPMN) are actually reported. CASE DESCRIPTION: We report a patient diagnosed with double cystic brain lesions that the histological examination reveal to be consistent, with pancreatic metastasis. Our patient had an history shown of stable pancreatic IPMN which has never made the oncologist suspicious about neoplastic progression or degeneration into pancreatic carcinoma. Considering the rarity of these metastasis we did a literature review on the topic. CONCLUSIONS: Despite rare, pancreatic origin of a cystic brain metastasis should considered in differential diagnosis in both patient with IPMN or patient with unknown primitive tumor.

Targeted Muscle Reinnervation and Osseointegration for Pain Relief and Prosthetic Arm Control in a Woman with Bilateral Proximal Upper Limb Amputation.

BACKGROUND: Bilateral proximal upper limb loss is a dramatic life-changing event. Replacement of the lost function with prosthetic arms, including multiple mechatronic joints, has remained a challenge from the control, comfort, and pain management perspectives. Targeted muscle reinnervation (TMR) is a peripheral nerve surgical procedure proposed to improve the intuitive control of the prosthetic arm and for neuroma and phantom pain management. Moreover, osseointegrated percutaneous implants (OPIs) allow for direct skeletal attachment of the prosthetic arm, ensuring freedom of movement to the patient's residual articulations. CASE DESCRIPTION: We have reported the first combined application of TMR and an OPI to treat a 24-year-old woman with a bilateral amputation at the shoulder level on the right side and at the very proximal transhumeral level on the left side. TMR was performed bilaterally in a single day, accounting for the peculiar patient's anatomy, as preparatory stage to placement of the OPI, and considering the future availability of implantable electromyographic sensors. The 2 OPI surgeries on the left side were completed after 8.5 months, and prosthetic treatment was completed 17 months after TMR. CONCLUSIONS: The use of TMR resolved the phantom pain bilaterally and the right-side neuroma pain. It had also substantially reduced the left side neuroma pain. The actual prosthetic control result was intuitive, although partially different from expectations. At 2 years after TMR, the patient reported improvement in essential activities of daily living, with a remarkable preference for the OPI prosthesis. Only 1 suspected case of superficial infection was noted, which had resolved. Overall, this combined treatment required a highly competent multidisciplinary team and exceptional commitment by the patient and her family.

Natural History, Clinical, and Surgical Management of Cavernous Malformations.

We describe Natural history, clinical and surgical management of cavernous malformation of the brain and spinal cord. Decision-making for treatment of cavernous malformations cannot ignore their natural history and risk of bleeding, which is different depending on the location. Surgical morbidity also depends on the position of the lesion. We performed a review of hemorrhage risk and clinical assessment of superficial and deep supratentorial, brainstem and intramedullary cavernous malformations.

Principles of Cortical Plasticity in Peripheral Nerve Surgery.

Cortical plasticity is a finely regulated process that allows the central nervous system (CNS) to change in response to internal and external stimuli. While these modifications occur throughout normal brain development, interestingly, they are also elicited after peripheral nerve injury and surgery. This article provides an overview of the principle mechanisms of synaptic, neuronal, cortical and subcortical neuroplasticity, with special attention to cortical and subcortical modifications-as suggested by modern neuroimaging techniques-after peripheral nerve surgery. The main nerve transfer techniques for the superior extremities and their effect on cortical plasticity are also described.

Transfer of the peroneal component of the sciatic nerve in total brachial plexus lesion: An anatomical feasibility study.

Closed brachial plexus lesions (BPLs) are generally associated with a traumatic mechanism of forced traction between the neck and the shoulder-arm complex. For brachial plexus reconstruction different techniques have been proposed with donor motor nerves like intercostal nerves, or the ipsilateral cervical plexus, the phrenic nerve, the contralateral C7 root, and many others. Despite all these surgical possibilities, the overall recovery is generally poor and not satisfactory. The principal drawback is linked to the loss of upper limb proprioception, in a way that dramatically influences even a good motor recovery, so in complete BPLs the sensory loss still represents a debilitating problem. In this anatomical feasibility study, the possibility to transfer the peroneal component of the sciatic nerve as a donor for complete BPLs has been evaluated. This technique would conceptually bring an important motor and sensory contribution to the upper limb using pure motor and sensory branches of the sciatic nerve. Performing immediate tendon transfer for foot drop palsy could significantly decrease the morbidity of the surgical procedure.

Morphometric and Radiomorphometric Study of the Correlation Between the Foramen Magnum Region and the Anterior and Posterolateral Approaches to Ventral Intradural Lesions.

AIM: To identify the range of dimensional morphometric variability correlated to the basilar and condylar part of the occipital bone, which may affect the choice of approach to ventral intradural foramen magnum (FM) lesions. MATERIAL AND METHODS: In total, 25 dry skulls and 50 head computed tomography (CT) scan results have been assessed in detail, focusing on the FM, occipital condyles, jugular tubercles (JT), and hypoglossal canals (HC). A morphometric analysis has been carried out using linear and angular measurements to estimate the range of the dimensional variability of these structures. Data were presented as mean ± standard deviation, ranges, and interquartile range on a boxplot. The sagittal intercondylar angle (SICA) and anterior condylar angle (ACA) have been found to be important in estimating the axial orientation of the condyles, whereas the JT-HC interline ratio has indicated the prominence of the tubercles. RESULTS: The SICA and ACA have exhibited high variability. The average JT-HC interline ratio was 0.8. Wider SICA-ACA and higher JT-HC interline ratio make the posterolateral approach advantageous. An anterior medial or far-medial endoscopic route is indicated in opposite conditions. In this study, two illustrative cases have been reported. CONCLUSION: A cautious preoperative morphometric evaluation of the FM region must be considered prior to using tailored and safe anterior endoscopic and posterolateral approaches to ventral intradural lesions to identify the advantages of a certain corridor as much as possible, thereby minimizing the risk of complications.

Intraoperative ultrasound and 5-ALA: the two faces of the same medal?

BACKGROUND: High Grade Gliomas (HGG) still remain the most demanding neuro-oncological challenge. Several studies have confirmed that the extent of resection (EOR) correlates with increased survival in patients with HGGs. The Gross Total Resection (GTR) of HGGs can be difficult and challenging. For this reason, technologies to improve EOR have been of interest. The aim of this paper is to analyze advantages and limitations of both intra-operative fluorescence and intra-operative ultrasound (IOUS) resection techniques. METHODS: Our work deals with the comparison of one group of 15 patients treated with both tools (study group) with a control group of 15 patients in where only fluorescence was used. Post operative outcome are valued using Karnofsky Performance Status scale (KPS) while EOR are valued with MRI within 24 h after surgery. RESULTS: The difference between the postoperative KPS and between EOR in the 2 groups resulted not statistically significant considering p<0.05. In our experience 5-ALA has a limited sensitivity before starting resection while shows it's central role in identifying the tumor remnants after its removal. Conversely, IOUS is very useful in identifying the tumor before starting resection. After the tumor removal, the sensitivity of the ultrasound in identifying tumor remnants in the margins of the cavity decreased significantly. However, in one case, at the end of resection, we have not visualized any fluorescent tissue but we detect a residual of tumor using the IOUS. CONCLUSIONS: In our preliminary experience we observe that there are no significative advantages using IOUS plus 5-ALA. However we feel that IOUS is useful in first step of resection and fluorescence in the latest steps of operation. Therefore these two technologies could be considered the two faces of the same medal because they can help the surgeon to detect the tumor in all step of tumor removal.

Intraneural Ewing Sarcoma of Fibular Nerve: Case Report, Radiologic Findings and Review of Literature.

BACKGROUND: Intraneural Ewing sarcoma (ES) was first described in 1918 by Stout in a tumor of the ulnar nerve. These tumors are in the category of ES family of tumors, together with ES of bone, extraosseous ES, and primitive neuroectodermal tumor. ES typically occurs in the second decade of life; only 20% of cases affect elder people. The most frequently involved sites are the craniospinal vault and cauda equina, while the peripheral nerve location is extremely rare (only 11 cases mentioned in the literature to date). CASE DESCRIPTION: This case report documents a rare case of a 46-year-old woman with an intraneural extraosseous ES and offers a complete radiologic documentation including contrast magnetic resonance imaging and microbubble contrast-enhanced ultrasonographic data. A review of the literature about diagnostic and treatment management is presented. CONCLUSIONS: The challenge of intraneural extraosseous ES consists of the right balance between the necessity to consider a potential malignant nature of the lesion and perform adequate surgical excision in a relatively brief time from the first clinical examination and the fact that these are extremely rare pathologic entities among most frequent cases of completely benign tumors, which could even have the same clinical and radiologic presentation. For this reason, a multidisciplinary setting with a team of neurosurgeons, orthopedic specialists, radiologists, pathologists, and oncologists should manage these cases as soon as a pathologic diagnosis is available. More attention should be focused on other therapies that effectively manage microscopic pathologic involvement, without increasing the risk of postoperative morbidity.