Background: Peripheral nerve lesions are associated with debilitating long-term consequences. Albeit being essential for evidence-based clinical decision making, epidemiological and etiological data are scarce. We therefore aimed to comprehensively analyze epidemiological and etiological factors of peripheral nerve lesions in one of the largest cohorts. Methods: We screened a total of 110,667 patients treated at our level I trauma center between January 2012 and July 2020 for nerve lesions. Subsequently, demographics, etiologies, concomitant injuries, and lesion characteristics were analyzed. Results: A total of 5026 patients, predominantly young males suffering from non-work-related nerve injuries, were treated. Proximal levels of injury were more likely to be accompanied by fractures, whereas more distal injuries with concomitant vessel or tendon injury. Main causes were 54.6% lacerations. Acute traumatic nerve injury was treated within 24 h in 55.9% of cases. Conclusions: Given the young age of affected patients, early diagnosis and treatment in specialized centers may facilitate their early return to work and improve long-term functional outcomes. The data show the importance of a special attention on nerve injuries, which may be masked by large accompanying injuries. New findings on lesion characteristics of selected subgroups and accompanying circumstances can support a change in treatment strategies.

Introduction: If tensionless nerve coaptation is not possible, bridging the resulting peripheral nerve defect with an autologous nerve graft is still the current gold standard. The concept of conduits as an alternative with different materials and architectures, such as autologous vein conduits or bioartificial nerve conduits, could not replace the nerve graft until today. Chitosan, as a relatively new biomaterial, has recently demonstrated exceptional biocompatibility and material stability with neural lineage cells. The purpose of this prospective randomized clinical experiment was to determine the efficacy of chitosan-based nerve conduits in regenerating sensory nerves in the hand. Materials and methods : Forty-seven patients with peripheral nerve defects up to 26 mm distal to the carpal tunnel were randomized to receive either a chitosan conduit or an autologous nerve graft with the latter serving as the control group. Fifteen patients from the conduit group and seven patients from the control group were available for a 12-month follow-up examination. The primary outcome parameter was tactile gnosis measured with two-point discrimination. The secondary outcome parameters were Semmens Weinstein Monofilament Testing, self-assessed pain, and patient satisfaction. Results: Significant improvement (in static two-point discrimination) was observed six months after trauma (10.7 ± 1.2 mm; p < 0.05) for chitosan-based nerve conduits, but no further improvement was observed after 12 months of regeneration (10.9 ± 1.3 mm). After six months and twelve months, the autologous nerve graft demonstrated comparable results to the nerve conduit, with a static two-point discrimination of 11.0 ± 2.0 mm and 7.9 ± 1.1 mm. Semmes Weinstein Filament Testing in the nerve conduit group showed a continuous improvement over the regeneration period by reaching from 3.1 ± 0.3 after three months up to 3.7 ± 0.4 after twelve months. Autologous nerve grafts presented similar results: 3.3 ± 0.4 after three months and 3.7 ± 0.5 after twelve months. Patient satisfaction and self-reported pain levels were similar between the chitosan nerve conduit and nerve graft groups. One patient required revision surgery due to complications associated with the chitosan nerve tube. Conclusion: Chitosan-based nerve conduits are safe and suitable for bridging nerve lesions up to 26 mm in the hand. Tactile gnosis improved significantly during the early regeneration period, and functional outcomes were similar to those obtained with an autologous nerve graft. Thus, chitosan appears to be a sufficient substitute for autologous nerve grafts in the treatment of small nerve defects in the hand.

Background: Peripheral nerve pathology is frequently encountered in clinical practice among peripheral nerve and extremity surgeons. One major factor limiting nerve regeneration and possibly leading to revision surgeries is the development of traumatic or postoperative adhesions and scarring around nerves. In experimental models, different materials have been studied to limit scar tissue formation when wrapped around nerves. Methods: A systematic review of studies describing nerve-wrapping materials in a non-transectional rat sciatic nerve model was performed following the PRISMA guidelines. Literature describing nerve-wrapping methods for the prevention of peripheral nerve scarring in rat sciatic nerve models was identified using PubMed and Web of Science, scanned for relevance and analyzed. Results: A total of 15 original articles describing 23 different materials or material combinations for nerve wrapping were included. The heterogeneity of the methods used did not allow a meta-analysis, thus, a systematic review was performed. Out of 28 intervention groups, 21 demonstrated a preventive effect on scar tissue formation in at least one qualitative or quantitative assessment method. Conclusions: The analyzed literature describes a variety of materials from different origins to limit peripheral nerve scarring and adhesions. Thus, a scar-preventive effect by wrapping peripheral nerves as adhesion prophylaxis seems likely. However, a quantitative comparison of the studies to identify the optimal material or technique is not possible with the diversity of used models and study designs. Therefore, further research needs to be performed to identify the optimal nerve wraps to be used routinely in clinical practice.

Scar tissue formation presents a significant barrier to peripheral nerve recovery in clinical practice. While different experimental methods have been described, there is no clinically available gold standard for its prevention. This study aims to determine the potential of fibrin glue (FG) to limit scarring around peripheral nerves. Thirty rats were divided into three groups: glutaraldehyde-induced sciatic nerve injury treated with FG (GA + FG), sciatic nerve injury with no treatment (GA), and no sciatic nerve injury (Sham). Neural regeneration was assessed with weekly measurements of the visual static sciatic index as a parameter for sciatic nerve function across a 12-week period. After 12 weeks, qualitative and quantitative histological analysis of scar tissue formation was performed. Furthermore, histomorphometric analysis and wet muscle weight analysis were performed after the postoperative observation period. The GA + FG group showed a faster functional recovery (6 versus 9 weeks) compared to the GA group. The FG-treated group showed significantly lower perineural scar tissue formation and significantly higher fiber density, myelin thickness, axon thickness, and myelinated fiber thickness than the GA group. A significantly higher wet muscle weight ratio of the tibialis anterior muscle was found in the GA + FG group compared to the GA group. Our results suggest that applying FG to injured nerves is a promising scar tissue prevention strategy associated with improved regeneration both at the microscopic and at the functional level. Our results can serve as a platform for innovation in the field of perineural regeneration with immense clinical potential.

Background: Severe burn injuries often lead to lasting physical and psychological consequences. Post-traumatic stress disorder (PTSD) is common among burn survivors and may be influenced by persistent somatic complaints. This study examined whether PTSD is associated with a higher burden of physical symptoms during and after inpatient rehabilitation. Methods: We conducted a subgroup analysis of a multicenter prospective cohort study involving 103 adult burn patients in inpatient rehabilitation. Based on Impact of Event Scale—Revised (IES-R) scores and clinical evaluation, patients were grouped as PTSD (n = 43) or No PTSD (n = 60). Physical symptoms assessed included skin dryness (xerosis), temperature sensitivity (cold/heat), numbness, skin tightness, and increased sweating. Results: Patients with PTSD reported significantly more physical symptoms at follow-up than those without PTSD: xerosis (74% vs. 50%, p = 0.03), cold sensitivity (61% vs. 35%, p = 0.02), heat sensitivity (63% vs. 39%, p = 0.03), numbness (63% vs. 33%, p = 0.006), skin tightness (82% vs. 52%, p = 0.004), and sweating (45% vs. 19%, p = 0.01). PTSD patients also had more severe burns, reflected in higher full-thickness TBSA (2% vs. 0%, p = 0.03) and elevated ABSI scores (median 6 vs. 5, p = 0.04). Conclusion: PTSD is associated with a higher and more persistent burden of physical skin symptoms after severe burns. These findings underscore the importance of early PTSD screening and integrated psychological-somatic rehabilitation to improve long-term recovery and quality of life.