Orthopterans are suitable model organisms for investigations of regeneration mechanisms in the auditory system. Regeneration has been described in the auditory systems of locusts (Caelifera) and of crickets (Ensifera). In this study, we comparatively investigate the neural regeneration in the auditory system in the bush cricket Mecopoda elongata. A crushing of the tympanal nerve in the foreleg of M. elongata results in a loss of auditory information transfer. Physiological recordings of the tympanal nerve suggest outgrowing fibers 5 days after crushing. An anatomical regeneration of the fibers within the central nervous system starts 10 days after crushing. The neuronal projection reaches the target area at day 20. Threshold values to low frequency airborne sound remain high after crushing, indicating a lower regeneration capability of this group of fibers. However, within the central target area the low frequency areas are also innervated. Recordings of auditory interneurons show that the regenerating fibers form new functional connections starting at day 20 after crushing.

BACKGROUND Postoperative pancreatic fistula (POPF) remains a significant source of morbidity following distal pancreatectomy (DP). There is a lack of information regarding the impact of trauma on POPF rates when compared with elective resection. We hypothesize that trauma will be a significant risk factor for the development of POPF following DP. METHODS A retrospective, single-institution review of all patients undergoing DP from 1999 to 2017 was performed. Outcomes were compared between patients undergoing DP for traumatic injury to those undergoing elective resection. Univariate and multivariable analyses were performed using SAS (version 9.4). RESULTS Of the 372 patients who underwent DP during the study period, 298 met inclusion criteria: 38 DPs for trauma (TDP), 260 elective DPs (EDP). Clinically significant grade B or C POPFs occurred in 17 (44.7%) of 38 TDPs compared with 41 (15.8%) of 260 EDPs (p < 0.0001). On multivariable analysis, traumatic injury was found to be independently predictive of developing a grade B or C POPF (odds ratio, 4.3; 95% confidence interval, 2.10–8.89). Age, sex, and wound infection were highly correlated with traumatic etiology and therefore were not retained in the multivariable model. When analyzing risk factors for each group (trauma vs. elective) separately, we found that TDP patients who developed POPFs had less sutured closure of their duct, higher infectious complications, and longer hospital stays, while EDP patients that suffered POPFs were more likely to be male, younger in age, and at a greater risk for infectious complications. Lastly, in a subgroup analysis involving only patients with drains left postoperatively, trauma was an independent predictor of any grade of fistula (A, B, or C) compared with elective DP (odds ratio, 8.6; 95% confidence interval, 3.09–24.15), suggesting that traumatic injury is risk factor for pancreatic stump closure disruption following DP. CONCLUSION To our knowledge, this study represents the largest cohort of patients comparing pancreatic leak rates in traumatic versus elective DP, and demonstrates that traumatic injury is an independent risk factor for developing an ISGPF grade B or C pancreatic fistula following DP. LEVEL OF EVIDENCE Prognostic study, Therapeutic, level III.

Background: High-frequency (10-kHz) spinal cord stimulation (SCS) continues to be an emerging therapy in chronic pain management. The same complications that plagued earlier SCS systems may affect newer stimulation technologies, although there is limited data on the type of complications and surgical management of these complications. Objective: The aim of this study was to systematically examine real-world complications associated with 10-kHz SCS reported on the Manufacturer and User Facility Device Experience (MAUDE) database. Materials and Methods: The MAUDE database was queried for entries reported between January 1, 2016 and December 31, 2020. Entries were classified into procedural complications, device-related complications, patient complaints, surgically managed complications, serious adverse events, and/or other complications. Primary outcomes included type and frequency of complications, and surgical management of complications. Results: A total of 1651 entries were analyzed. Most entries were categorized as procedural complications (72.6%), followed by serious adverse events (10.5%), device-related complications (10.5%), and patient complaints (9.9%). Most complications were managed surgically with explant (50.9%) rather than revision (5.0%) or incision/drainage (6.6%). Of procedural complications, the most common entries included non-neuraxial infection (52.9%), new neurological symptoms (14.7%), and dural puncture (9.5%). Of device-related complications, the most common entries included lead damage (41.6%), erosion (18.5%), and difficult insertion (11.5%). Conclusion: This retrospective 5-year analysis of complications from10-kHz SCS provides a real-world assessment of safety data unique for this stimulation modality. This analysis may help inform future clinical decisions, lead to device enhancement and optimization, and improve mitigation of risks to provide safe and efficacious use of 10-kHz SCS.