The usefulness and effectiveness of interactive telemedicine in surgery classes - a survey of Polish medical students.

<b>Introduction:</b> Computer-based interactive techniques are becoming an important tool in medical education. One of the important benefits of the use of telemedicine in surgical training is the reduction of the number of people in the operating room. As shown in the studies, this can lead i.a. to the reduction in the risk of surgical site infections.<b>Aim:</b> The aim of this survey as held among fifth-year medical students at three academic centers was to assess the usefulness and effectiveness of telemedicine as a surgery-teaching tool.<b>Material and methods:</b> A transmission of a surgical procedure was carried out by each of the three participating centers according to a previously prepared schedule. Each transmission was preceded by the diagnostics, indications, and the course of the surgical procedure being discussed by the facilitator physician who also coordinated the transmission throughout the procedure. After the class, students received anonymous surveys consisting of fourteen questions as per the attached protocol so as to evaluate the class using the rating scale of 1 (the lowest rating) through 5 (the highest rating). The survey assessed the educational value (the knowledge acquired from the class), the form (interactivity, facilitator complicity), and the usefulness of the class for overall surgical education.<b>Results:</b> The survey was completed by 232 students, with 95% of respondents rating the usefulness of telemedicine classes in surgical education as very good or good. As many as 97% of students declared that the transmission had been a good or a very good tool in terms of delivery or adding to their knowledge of topographical anatomy and basic aspects of surgical technique. Higher ratings were given to the usefulness of comments and remarks by the facilitating physician (96% of very good or good ratings) who had been watching the procedure along with the students as compared to those provided by the operating physician (81%).<b>Discussion:</b> The use of telemedicine-based teaching models in surgical education facilitates a better view of the operating field for the students, greater accessibility of educational content delivered simultaneously to multiple groups of students, increased safety of the surgical procedure by reducing the number of people in the operating room as well as reduced burden on the operating physician (thanks to the introduction of class facilitator).<b>Conclusions:</b> In our opinion, the advantages of the presented teaching model are: better view (particularly in case of open procedures), ability to pinpoint surgical field structures (on the participants' and operator's monitors), absence of additional people (students) in the operating room (increasing the safety of the procedure and reducing the risk of surgical site infections) and the ability to go back to recorded operations and perform various types of educational analyses.

Analysis of risk factors for surgical site infection and other postoperative complications in patients following loop ileostomy reversal.

<b>Introduction:</b> Loop ileostomy reversal (LIR) procedure is still associated with a relatively high risk of complications. Surgical site infection (SSI) is the most common complication in this group of patients. SSI leads to prolonged hospital stays, delays the adjuvant therapy, and increases hospital costs.<b>Aim:</b> The aim of the study was to analyze the risk factors for SSI in patients following loop ileostomy reversal procedure.<b>Material and methods:</b> A single-center retrospective analysis was conducted in a tertiary reference center. Finally, 65 patients following loop ileostomy reversal procedure performed between 2018 and 2022 were enrolled in the study. Data were collected retrospectively based on the available medical charts. The study group comprised 23 women (35%) and 42 men (65%) with a mean age of 48.9 14.5 years and a mean body mass index of 24.3 4.9 kg/m² . The most common indication for index surgery was ulcerative colitis (33%) and colorectal cancer (29%). Preferably, handsewn anastomosis was performed (n = 42; 64.6%).<b>Results:</b> The most important parameter evaluated in the above study was the diagnosis of surgical site infection, which influenced e.g. hospitalization after surgery, the need for antibiotic therapy, or C-reactive protein (CRP) values. Nine patients (13.8%) were diagnosed with SSI during their hospital stay (more than 86% without SSI). In the group with SSI, hospital stay exceeded 13 days compared to almost 6 days in the group without SSI (P = 0.00009). The time of the procedure had a statistically significant correlation with antibiotic therapy introduction (P = 0.01). The type of intestinal anastomosis had a significant impact on the operative time (P = 0.0011) and the time of hospital stay after surgery (P = 0.04).<b>Conclusions:</b> Most of the analyzed clinical factors were directly related to the impact on the duration of postoperative hospitalization. The duration of hospitalization is an independent and undeniable factor increasing the risk of other postoperative complications and significantly increasing the cost of hospitalization. Another factor that has a large clinical impact on postoperative treatment is the presence of comorbidities which make patients more likely to develop SSI, CRP increase, or the need for antibiotic therapy. An important factor was the level of CRP, the elevated value of which may be a predictor of many negative aspects in postoperative treatment.

Negative Pressure Level and Effects on Bacterial Growth Kinetics in an in vitro Wound Model.

Negative Pressure Wound Therapy (NPWT) has been widely adopted in wound healing strategies due to its multimodal mechanism of action. While NPWT's positive impression on wound healing is well-established, its effect on bacterial load reduction remains equivocal. This study investigates NPWT's efficacy in reducing bioburden using an in vitro porcine skin model, focusing on the impact of Staphylococcus aureus and Staphylococcus epidermidis. Custom-made negative pressure chambers were employed to apply varying negative pressures. Porcine skin was cut into 5 × 5 cm squares and three standardized wounds of 6 mm each were created using a biopsy punch. Then, wounds were infected with S. aureus and S. epidermidis bacterial suspensions diluted 1:10,000 to obtain a final concentration of 1.5 × 104 CFU/ml and were placed in negative pressure chambers. After incubation, bacterial counts were expressed as colony-forming units (CFU) per ml. For S. aureus at 120 hours, the median CFU, mean area per colony, and total growth area were notably lower at -80 mmHg when compared to -250 mmHg and -50 mmHg, suggesting an optimal negative pressure for the pressure-dependent inhibition of the bacterial proliferation. While analyzing S. epidermidis at 120 hours, the response to the negative pressure was similar but less clear, with the minor CFU at -100 mmHg. The influence of intermittent negative pressure on the S. epidermidis growth showed notably lower median CFU with the interval therapy every hour compared to the S. aureus control group. This study contributes valuable insights into NPWT's influence on the bacterial load, emphasizing the need for further research to reformulate its role in managing contaminated wounds.

Analysis of risk factors for conversion in laparoscopic adrenalectomy: a single-institution series of 256 patients.

Introduction: Although introduction of the laparoscopic approach for adrenal gland surgery revolutionized the strategy in management of adrenal gland tumors, open surgery is still a method of choice in some clinical scenarios. Moreover, laparoscopy may have limitations resulting in conversion. Aim: To assess risk factors predisposing for conversion based on our own material, including 256 laparoscopic adrenalectomies performed in 2009-2016. Material and methods: A retrospective analysis of patients who underwent adrenalectomies between 2009 and 2016 was conducted. Patients were analyzed for sex, body mass index (BMI), size of the adrenal gland lesion, final histopathological diagnosis and operated side of the adrenal gland, its impact on conversion rate. Results: A total of 256 patients underwent laparoscopic adrenalectomy. The reported study comprised of 94 (36.7%) men and 162 (63.3%) women. The most common indication for adrenalectomy were adrenal cortex adenoma (n = 149; 58.2%) and pheochromocytoma (n = 48; 18.75%). The conversion rate was 3.91% (n = 10 patients). Mean BMI of patients without conversion was 27.6 kg/m2, whereas in the group of patients with conversion, BMI was 29.7 kg/m2 (p > 0.05). The conversion rate was precisely the same when comparing the right (5/126; 3.9%) and left (5/126; 3.9%) adrenal gland. There was no correlation between the size of the adrenal lesion and the risk of conversion. Conclusions: The laparoscopic approach remains an efficient and safe procedure for adrenal gland tumors. Based on our study, obese patients and those with pheochromocytoma are associated with a higher risk of conversion but without any statistical significance. There was no difference in the conversion rate when analyzing the size of the adrenal gland tumor. No difference was also revealed in the conversion rate when comparing both sides of laparoscopic adrenalectomy.

Stoma close to the abdominal wound: a real technical problem. A description of a novel care strategy.

IntroductionIn some clinical scenarios, stoma site may be located close to the abdominal wound edge impeding optimal wound management and stoma care. We present a novel strategy of utility NPWT for management of simultaneous abdominal wound healing with stoma presence. Material and methodsRetrospective analysis of seventeen patients treated with a novel wound care strategy was conducted. Application of NPWT within wound bed, around stoma site and skin between allows for: 1) separating wound from stoma site, 2) maintaining the optimal environment for wound healing, 3) protecting peristomal skin and 4) facilitating application of ostomy appliances.ResultsThe study group comprised of twelve female (70,6 %) and five male (29,4%) with the mean age of 49.1 18.4 years The most common underlying pathology was Crohn s disease (n-5; 29,4%). Since NPWT was implemented, patients had undergone from 1 to 13 surgeries. Thirteen patients (76,5%) required intensive care unit admission. The mean time of hospital stay was 65,3 28,6 days (range: 36 134). The mean session of NPWT was 10.8 5.2 (range: 5 - 24) per patient. The range of the level of negative pressure was from -80 to 125 mmHg. In all patients, progress in wound healing was achieved resulting in granulation tissue formation, minimizing wound retraction and thus reduction of the wound area. As a result of NPWT, wound was granulated entirely, tertiary intension closure were achieved or patients were qualified for reconstructive surgery.DiscussionNPWT is safe and useful therapy for complicated abdominal wounds with the presence of stoma close to wounds edges. A novel care strategy allows for simultaneous technical opportunity to separate stoma from wound bed and facilitate wound healing.

Challenges in restoring bowel continuity: An analysis of 91 patients undergoing a reversal procedure

Introduction: The restoration of bowel continuity is associated with significant postoperative morbidity. Aim: The aim of the study was to report the outcomes of restoring intestinal continuity in a large patient cohort. Material and methods: A retrospective analysis was conducted on 91 patients with terminal stoma who were qualified for restoration of GI tract continuity between January 2015 and March 2020. The following demographic and clinical characteristics were analyzed: age, gender, BMI, comorbidities, indication for stoma creation, operative time, the need for blood replacement, the site and type of the anastomosis, and complication and mortality rates. Results: The study group was comprised of 40 women (44%) and 51 men (56%). The mean BMI was 26.8 ±4.9 kg/m2. Only 29.7% of the patients (n = 27) were at normal weight (BMI: 18.5­24.9) and only 11% (n = 10) did not suffer from any comorbidities. The most common indications for index surgery were complicated diverticulitis (37.4%) and colorectal cancer (21.9%). The stapled technique was used in the majority of patients (n = 79, 87%). The mean operative time was 191.7 ±71.4 min. Nine patients (9.9%) required blood replacement peri- or postoperatively, whereas 3 patients (3.3%) required intensive care unit admission. The overall surgical complication rate was 36.2% (n = 33) and the mortality rate was 1.1% (n = 1). Discussion: Restoration of bowel continuity is quite a demanding and complex procedure and thus should be performed by an experienced surgical team. In the majority of patients, the complication rate represents only minor complications. The morbidity and mortality rates are acceptable and comparable to other publications.

Effect of closed incision negative pressure wound therapy on incidence rate of surgical site infection after stoma reversal: a pilot study.

INTRODUCTION: The stoma reversal (SR) procedure is associated with a relatively high risk of perioperative complications with surgical site infection (SSI) as the most common. Recently closed incision negative pressure wound therapy (ciNPWT) was applied widely to prevent SSI. AIM: To investigate the efficiency of ciNPWT in terms of the incidence rate of SSI after SR surgery. MATERIAL AND METHODS: As an exploratory observational cohort study patients were treated either with ciNPWT (n = 15) or standard sterile dressing (SSD) (n = 15). CiNPWT was applied every 3 days whereas SSD was changed every day. Clinical evaluation for SSI signs, C-reactive protein level and pain assessment using the visual analogue scale (VAS) were analyzed. RESULTS: The incidence rate of SSI was in 13% (2/15) in the ciNPWT group and 26% (4/15) in the SSD group (p = 0.651, OR = 0.44, 95% CI: 0.03-3.73). All patients in the SSD group who developed SSI presented both local and generalized signs of infection. Pain-VAS levels assessed on the 1st (MdnciNPWT = 4, MdnSSD = 5, p = 0.027, W = 51.5) and 3rd postoperative day (MdnciNPWT = 2, MdnSSD = 4, p = 0.014, W = 45.5) were significantly lower in the ciNPWT group than in the SSD group. CONCLUSIONS: CiNPWT seems not to have a benefit to reduce SSI after the SR procedure. Further investigation is needed to establish firmly the benefit of using ciNPWT in this group of patients.

Endoscopic vacuum therapy with instillation (iEVT) - a novel endoscopic concept for colorectal anastomotic leak and perianal complications.

INTRODUCTION: Anastomotic leaks remain the most fearful complications. AIM: We present a novel endoscopic salvage therapy known as endoscopic vacuum therapy with instillation (iEVT) as a combination of standard endoscopic vacuum therapy (EVT) and negative pressure wound therapy with instillation (iNPWT). MATERIAL AND METHODS: A case series of 6 consecutive patients treated with iEVT is presented. A Redon drain and a central venous catheter were introduced within polyurethane foam used as a self- made device for iEVT and antimicrobial solution was instilled. RESULTS: A total of 6 patients with the mean age of 29.5 ±8.9 were treated with iEVT. The mean number of iEVT sessions was 5.8 ±2.3. The mean time of iEVT management was 20.7 ±8.8 days. Locally, a reduction in purulent discharge and defect's dimension with contraction were revealed confirmed with imaging studies. CONCLUSIONS: iEVT is a very encouraging, novel method for complicated perianal diseases and anastomotic leak.

LapVac - a laparoscopic approach for negative pressure wound therapy application in open abdomen management: a porcine animal model.

INTRODUCTION: Negative pressure wound therapy (NPWT) in the open abdomen (OA) is recognized as a gold standard management method. Currently minimally invasive procedures are implemented in many clinical scenarios. AIM: To demonstrate the feasibility of using negative pressure wound therapy in a laparoscopic approach for OA management in a porcine model termed as a laparoscopic vacuum (LapVac). MATERIAL AND METHODS: An adult female swine underwent a laparoscopic procedure. Briefly, a small incision was made and secured with a wound protector, pneumoperitoneum was created and two additional ports were placed. Then, a non-adhesive layer was precisely placed within the abdominal cavity. RESULTS: Finally, polyurethane foam and adhesive drape were applied. A volume of 200 ml of saline solution was instilled and drained completely within 30 min. We did not observe any technical problems with NPWT application. CONCLUSIONS: This study confirmed the technical feasibility of NPWT application in the laparoscopic approach. LapVac seems to be a promising technique which may minimize the trauma and lead to better outcomes.

Efficacy of combined prophylactic therapy (rifaximine alpha + prebiotic arabinogalactan with lactofferin) on GUT function in patients with diagnosed symptomatic uncomplicated diverticular disease.

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Ileal pouch anal anastomosis leak after restorative proctocolectomy without protective stoma successfully treated with endoscopic vacuum therapy.

Aim An ileal pouch anal anastomosis (IPAA) leak is one of the most severe complication after restorative proctocoletomy (RPC). We present a rare case of a successful management of IPAA leak after RPC without defunctionig stoma with the utility of endoscopic vacuum therapy. Methods A 57-year-old male with a ileal pouch anal anastomosis leak after RPC due to ulcerative colitis with presacral abscess was qualified for endoscopic vacuum therapy (EVT). The abscess of the left buttock was drained and secured with suction drain (redon drain). Due to the lack of defunctioning stoma, a system for contain and divert fecal matter was placed within afferent limb of the J-pouch and EVT was placed directly within IPAA dehiscence. EVT was changed every third day. Results The patient underwent a total of five EVT sessions. Improvement of patient's general condition characterized with lack of pelvic pain, fever and reduction of inflammatory markers was achieved. Locally, anastomosis dehiscence was healed with prominent reduction in the defect's dimension, contraction and revascularization. Based on imaging studies no chronic presacral sinus or any other perianal disturbances were revealed at the time of five months follow up. Conclusions EVT is a promising method for management of IPAA leak. Although, it remains extremely difficult, EVT may serve as a method of choice in early pouch-related septic complications after RPC performed without defunctioning stoma.

A novel model of acellular dermal matrix plug for anal fistula treatment. Report of a case and surgical consideration based on first utility in Poland.

Anal fistula (AF) is a pathological connection between anus and skin in its surroundings. The main reason for the formation of anal fistula is a bacterial infection of the glands within the anal crypts. One of the modern techniques for the treatment of fistulas that do not interfere with the sphincters consists in implantation of a plug made from collagen material. We are presenting the first Polish experience with a new model of biomaterial plug for the treatment of anal fistula. We also point out key elements of the procedure (both preoperative and intraoperative) associated with this method. In the authors' opinion, the method is simple, safe and reproducible. Innovative shape of the plug minimizes the risk of its migration and rotation. It also perfectly blends with and adapts to the course and shape of the fistula canal, allowing it to become incorporated and overgrown with tissue in the fistula canal. The relatively short operation time, minor postoperative pain and faster convalescence are with no doubt additional advantages of the method. Long-term observation involving more patients is essential for evaluation of the efficacy of the treatment of fistulas with the new type of plug.

Epineural Sheath Jacket as a New Surgical Technique for Neuroma Prevention in the Rat Sciatic Nerve Model.

BACKGROUND: Terminal neuromas resulting from severe nerve injuries and traumatic or surgical limb amputations can become a source of pain, and significantly impair patients' quality of life. Recently, the number of patients with peripheral nerve injuries increased due to modern war conflicts, natural disasters, and traffic accidents. This study investigated the efficacy of the epineural sheath jacket (ESJ) as a novel technique for neuroma prevention in the rat sciatic nerve model. METHODS: A 20-mm segment of the right sciatic nerve was excised in 18 Lewis rats, and the animals were divided into 3 experimental groups (n = 6/group): group I-control, nerve stump without protection; group II-muscle burying group, nerve stump buried in the muscle; group III-ESJ group, nerve stump protected by ESJ. The ESJ was created from the excised sciatic nerve and applied as a "cap" over the proximal nerve stump. The presence of neuropathic pain was assessed weekly by pinprick test and Tinel sign, up to 24 weeks postsurgery. At 24 weeks, assessments, such as macroscopic evaluation, retrograde neuronal labeling analysis, histomorphometry, and neural/connective tissue ratio were performed. RESULTS: Epineural sheath jacket significantly reduced neuroma formation, which was associated with decreased Tinel sign (16.7%, P < 0.05) response compared with the nerve stump control. Moreover, ESJ reduced axonal sprouting, bulb-shaped nerve ending formation and perineural adhesions, as confirmed by macroscopic evaluation. Histological evaluation confirmed that nerve stumps protected with the ESJ showed less fibrosis and presented well-organized axonal structure. Neural/connective tissue ratio and retrograde neuronal labeling analysis revealed significantly improved results in the ESJ group compared to the control nerve stump group (P = 0.032 and P = 0.042, respectively). CONCLUSIONS: The protective effect of the ESJ against neuroma formation was confirmed by behavioral and histological analyses, showing outcomes comparable to the muscle burying technique-the criterion standard of neuroma management.

The influence of rifaximin on diverticulitis rate and quality of life in patients with diverticulosis.

Diverticulosis, its associated symptoms and complications are one of the most common pathologies of the gastrointestinal tract in more economically developed countries. Presence of diverticuli and their clinical consequences can be divided into four categories: 1) diverticulosis, i.e. an asymptomatic presence of diverticuli that are usually found by accident 2) symptomatic uncomplicated diverticulosis 3) diverticulitis (acute uncomplicated diverticulitis) 4) complications of diverticulitis (conditions requiring hospital stay). The aim of this study was to retrospectively analyze the efficacy of rifaximin in preventing diverticulitis in patients visiting proctology clinics. The diagnostic criterium for diverticulosis was confirmation by colonoscopy, barium enema or CT colography (virtual colonoscopy) as well as history of at least one documented episode of diverticulosis. History of diverticulosis was evaluated based on medical records, clinical symptoms, elevated level of CRP (>5.0) and/or diagnostic imaging (ultrasound, CT). After setting strict exclusion criteria, 248 patients were qualified for the study out of 686, and they were later divided into two groups: control group (group I - 145 patients) and studied group (group II - 103 patients receiving rifaximin prophylaxis). Diverticulitis rate was comparable in both groups over a period of 6 months before study (p = 0.1306) and 6 months of treatment (p=0.3044). Between the 6th and 12th month of treatment, a significantly lower rate of diverticulitis was noted in the group receiving rifaximin compared to control group (p<0.0001). Patients receiving rifaximin reported higher quality of life (which was assessed using the VAS scale) compared to control group after 12 months. The results confirmed the efficacy of riaximin in prevention of diverticulitis, even in the scheme of repeated courses every 3 months. Not only did application of rifaximin lower the rate of diverticulitis and its complications in patients after an episode of diverticulitis, but also it improved the patients' quality of life. It seems that diverticulitis prophylaxis based on rifaximin can be economically efficient, however, it requires further research.

Conservative Measures for Managing Constipation in Patients Living With a Colostomy.

PURPOSE: The purpose of this study was to determine the effect of a conservative regimen for the treatment of constipation in persons living with a colostomy. DESIGN: Prospective, noncontrolled, single-center study. SUBJECTS AND SETTING: The study sample comprised 35 patients with a colostomy who were diagnosed with constipation. Subjects with morphologic changes causing constipation such as stomal stenosis and neoplastic and inflammatory changes were excluded. The study was conducted in the Proctology and Stoma Outpatient Clinic at Poznan University of Medical Sciences. METHODS: Patients at our Stoma Outpatient Clinic underwent baseline evaluation, and those with symptoms of constipation (prolonged periods between bowel movements, passage of pasty or hardened fecal effluent, and associated symptoms such as abdominal discomfort or bloating, flatulence, and pain with passage of effluent into the stoma) received individualized dietary recommendations that typically included an increase in dietary fiber and fluid intake, along with increased fluid intake. The outcomes of dietary changes were evaluated during a follow-up visit 3 months later. If dietary changes alone did not improve constipation symptoms, we prescribed a psyllium-based bulk-forming agent, an osmotic stool softener, and a probiotic, with or without a prokinetic agent such as metoclopramide taken 3 times daily. RESULTS: Dietary interventions alone were deemed successful in 60% of study subjects (n = 21); the remaining 14 patients required additional treatment. CONCLUSIONS: Dietary modifications alone relieved constipation in more than half of a group of 35 patients with constipation. We therefore recommend a trial of dietary modifications prior to the initiation of pharmacotherapy in patients with a colostomy.

Management of enteroatmospheric fistula with negative pressure wound therapy in open abdomen treatment: a multicentre observational study.

The management of enteroatmospheric fistula (EAF) in open abdomen (OA) therapy is challenging and associated with a high mortality rate. The introduction of negative pressure wound therapy (NPWT) in open abdomen management significantly improved the healing process and increased spontaneous fistula closure. Retrospectively, we analysed 16 patients with a total of 31 enteroatmospheric fistulas in open abdomen management who were treated using NPWT in four referral centres between 2004 and 2014. EAFs were diagnosed based on clinical examination and confirmed with imaging studies and classified into low (<200 ml/day), moderate (200-500 ml/day) and high (>500 ml/day) output fistulas. The study group consisted of five women and 11 men with the mean age of 52·6 years [standard deviation (SD) 11·9]. Since open abdomen management was implemented, the mean number of re-surgeries was 3·7 (SD 2·2). There were 24 EAFs located in the small bowel, while four were located in the colon. In three patients, EAF occurred at the anastomotic site. Thirteen fistulas were classified as low output (41·9%), two as moderate (6·5%) and 16 as high output fistulas (51·6%). The overall closure rate was 61·3%, with a mean time of 46·7 days (SD 43·4). In the remaining patients in whom fistula closure was not achieved (n = 12), a protruding mucosa was present. Analysing the cycle of negative pressure therapy, we surprisingly found that the spontaneous closure rate was 70% (7 of 10 EAFs) using intermittent setting of negative pressure, whereas in the group of patients treated with continuous pressure, 57% of EAFs closed spontaneously (12 of 21 EAFs). The mean number of NPWT dressing was 9 (SD 3·3; range 4-16). In two patients, we observed new fistulas that appeared during NPWT. Three patients died during therapy as a result of multi-organ failure. NPWT is a safe and efficient method characterised by a high spontaneous closure rate. However, in patients with mucosal protrusion of the EAFs, spontaneous closure appears to be impossible to achieve.

Anatomic variations of brachial and lumbosacral plexus models in different rat strains.

PURPOSE: Selection of an appropriate model for preclinical assessment of new methods of peripheral nerve injury management is crucial. This report presents anatomic variations within brachial and lumbosacral plexuses in three selected rat strains Sprague Dawley (Hsd:Sprague Dawley SD), Lewis (LEW/SsNHsd), and Athymic Nude (Hsd:RH-Foxn1rnu ) rats. METHODS: Based on their strain eighteen rats were divided into three groups. A total of 90 brachial plexus nerves (axillary, musculocutaneous, median, ulnar, and radial nerves) and 72 lumbosacral plexus nerves (sciatic, tibial, common peroneal, and sural nerves) were analyzed for the length, diameter and correlation with the body weight. A detailed anatomic course of each nerve within the brachial and lumbosacral plexuses was outlined. RESULTS: The sural nerve was the longest nerve in all studied rat strains, whereas the sciatic nerve had the largest diameter. Comparison of all the nerves' length demonstrated that the Lewis rat sciatic and sural nerves were significantly shorter (P < 0.05). No significant differences in nerve diameters were found among the analyzed rat strain groups. Significant correlation was revealed between the length of sciatic nerve and the rats' weight, which is irrelevant to the rats' genetic background. CONCLUSIONS: This study confirmed that nerves' length within rat's brachial and lumbosacral plexus depends on the inter-individual variations within the rat strains rather than on the differences in the peripheral nerve development, which is inherent to the specific rat strain. Correlation between the nerve length and body weight, suggests that bigger rats should be considered for studies requiring access to the long nerves. © 2016 Wiley Periodicals, Inc. Microsurgery 37:327-333, 2017.