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The study was conducted for the determination of the main nerves of the lumbosacral plexus in the helmeted guineafowl. Five helmeted guineafowls were used. Fowls were anaesthetised and the a. carotis communis was cut for blood drainage. Body cavities were revealed and were fixated with 10% formaldehyde. Nerves forming the lumbosacral plexus were dissected and photographed. Results were named according to the Nomina Anatomica Avium. It was determined that the lumbosacral plexus forms by 8 synsacral ventral rami from the ventrolateral side of synsacrum which include (2-9) synsacral spinal nerves. It was seen that the lumbar plexus was formed by the ventral rami of the 2nd, 3rd and 4th spinal nerves, and the sacral plexus was formed by the ventral rami of the 5th, 6th, 7th, 8th and 9th synsacral spinal nerves. It was observed that following nerves of n. pubicus (ilioinguinalis), r. cutaneous femoris lateralis, r. cutaneous femoris medialis (n. saphenus), n. femoralis and n. obturatorius originate from the lumbar plexus, and following nerves of n. ischiadicus, the common branch of n. fibularis and n. tibialis originate from the sacral plexus. It was determined that the n. ischiadicus was formed by the truncus cranialis, medianus and caudalis. In conclusion, it was determined that there are macro anatomical differences between different avian species in the quantity, thickness and distribution of the spinal nerves that form the lumbosacral plexus, and in formations of the plexus, and in separations of nerve branches.

AIMS To analyze, in female rats, the anatomical and histological features of the urethra and its relationship with the vagina and clitoris, and its innervation. METHODS Seventeen adult female Wistar rats were used. Gross anatomy and acetylcholinesterase (AchE) histochemistry were performed to describe the urethral features, adjacent structures, and innervation. The histomorphometric characteristics of the urethra were determined in transversal, longitudinal, or coronal sections stained with Masson's Trichrome. RESULTS The female rat urethra is not a homogeneous tubular organ. The pre-pelvic and pelvic regions are firmly attached to the vagina with belt-like striated fibers forming a urethra-vaginal complex. The bulbar regions have curved segments and a narrow lumen. The clitoral region is characterized by a urethra-clitoral complex surrounded by a vascular plexus. The lumen area and thickness of the urethral layers significantly varied between regions (P

Background In male rats, the bulbourethral glands (Bu-Gs) are the unique accessory sexual glands surrounded by striated musculature. However, until now the role of this musculature was unknown. Objectives (i) To characterize the Bu-Gs striated muscular layer in male rats and determine its innervation and response to genital stimulation. (ii) To reveal the role of the Bu-Gs striated musculature in the release of glandular secretion. (iii) To elucidate the effect of bilateral ablation of the Bu-Gs on copulatory behavior and seminal fluid characteristics. Materials and methods Adult Wistar male rats were allocated in three experiments: in Experiment 1, the Bu-Gs striated musculature, innervation and reflex activity were determined by gross anatomy and histological and electrophysiological techniques; electromyographic activity of the Bu-Gs striated musculature was evoked with genital stimulation. In Experiment 2, Bu-Gs were analyzed after copulatory behavior of intact or animals with unilateral transected motor branch of the sacral plexus (MBSP). In Experiment 3, copulatory behavior and spermatobioscopy of males with bilateral ablation of the Bu-Gs or sham surgery were analyzed. Results The Bu-Gs striated fibers discharged in response to mechanostimulation of the prepuce, glans, and penile-urethra. Innervation of the Bu-Gs striated musculature originated from the MBSP; this nerve also innervates striated penile muscles. Unilateral transection of the MBSP significantly decreased the secretion from the ipsilateral Bu-G to the nerve transection. Bilateral ablation of Bu-Gs did not affect seminal plug formation but decreased semen viscosity. Discussion and conclusion The Bu-Gs striated musculature contributes to expel glandular secretion during sexual intercourse. The somatic control of Bu-Gs secretion is additional to the reported autonomic innervation supplied by the cavernosus nerve, which may underlie the synthesis of secretion as well as contraction of Bu-Gs smooth muscle.

We report the use of a sacral plexus catheter for continuous local anaesthetic infusion in a patient with a unilateral sacral ala fracture following a fall from a horse. Although sacral plexus blockade has been well described for lower limb surgery, an ultrasound‐guided continuous catheter technique for conservatively managed fractures has not been described. Despite appropriate oral analgesia, the patient reported severe pain, particularly in the right gluteal region, which meant she was unable to sit upright or take deep breaths. A sacral plexus catheter was inserted with ultrasound guidance and an initial bolus of 30 ml levobupivicaine 0.25% was delivered followed by infusion of 8 ml.h(−1) levobupivicaine 0.125%. Daily follow‐up and assessment were provided by the acute pain team. We judged the procedure to be a success as measured by an improvement in mobilisation, deep breathing, cough and patient satisfaction.

Purpose To investigate the feasibility of three-dimensional MR neurography (3D MRN) for the sacral plexus using sampling perfection with application-optimized contrasts using different flip angle evolution (SPACE) sequences, and to demonstrate structural abnormalities in the pelvic nerve of women with pelvic endometriosis. Materials and Methods Twenty patients with pelvic endometriosis and 20 healthy controls were examined by contrast-enhanced 3D short time inversion recovery T2-weighted imaging (CE 3D STIR T2WI) SPACE sequences on 3 Tesla MRI. Image quality and diagnostic confidence of the sequences in identifying abnormalities of the sacral plexus were analyzed and compared with conventional three-plane images of 2D turbo-spin echo T2-weighted images (2D TSE T2WI). The changes in the sacral plexus caused by endometrial lesions were evaluated. Results The sacral plexus was clearly revealed in both healthy controls and patients with endometriosis on 3D STIR SPACE images. A good agreement was reached in the evaluation of both imaging quality (Kappa value [κ] = 0.73–1.00) and diagnostic confidence (κ = 0.66–0.81) when compared between the two independent readers. Abnormalities caused by endometriosis were identified in 17 patients, unilaterally in 10 patients, and bilaterally in 7 patients. Nerve fiber abnormalities of lumbar 5 (L5) were detected in 11 patients, of sacral 1 (S1) in 14 patients and of sacral 2 (S2) in 9 patients. Conclusion CE 3D STIR SPACE sequences demonstrate its significant capacity to investigate and map the sacral plexus, and reveal the compression and adhesion of the sacral plexus nerve as a result of ectopic lesions. Level of Evidence: 3 J. Magn. Reson. Imaging 2016

Bilateral rounding of the shoulders (laxity) associated with kyphosis of the thoracic spine causes costoclavicular compression and brachial plexopathy. This form of thoracic outlet syndrome is usua...

The aim of this study was to explore the anatomical variations of the nerve to the levator ani (LA) and to relate these findings to LA dysfunction. One hundred fixed human female cadavers were dissected using transabdominal, gluteal, and perineal approaches, resulting in two hundred dissections of the sacral plexus. The pudendal nerve and the sacral nerve roots were traced from their origin at the sacral foramina to their termination. All nerves contributing to the innervation of the LA were considered to be the nerve to the LA. Based on the spinal nerve components, the nerve to the LA was classified into the following categories: 50% (n = 100) originated from S4 and S5 (type I); 19% (n = 38) originated from S5 (type II); 16% (n = 32) originated from S4 (type III); 11% (n = 22) originated from S3 and S4 (type IV); 4% (n = 8) originated from S3, S4, and S5 (type V). Two patterns of nerve termination were observed. In 42% of specimens, the nerve to the LA penetrated the coccygeus muscle and assumed an external position along the inferior surface of the LA muscle. In the remaining 58% of specimens, the nerve crossed the superior surface of the coccygeus muscle and continued along the superior surface of the iliococcygeus muscle. Damage to the nerve to LA has been associated with various pathologies. In order to minimize injuries during surgical procedures, a thorough understanding of the course and variations of the nerve to the LA is extremely important.

Endometriosis (EM) is an infrequent cause of peripheral neuropathy, most commonly sciatic. Perineural spread has recently been introduced as an alternate explanation for cases of lumbosacral or sciatic nerve EM. We performed a literature review to collect all reported cases of peripheral and central nervous system EM in search of anatomic patterns of involvement; potentially to support the perineural spread theory. If available, intraneural invasion and presence of peritoneal EM were recorded. The search revealed 83 articles describing 365 cases of somatic peripheral nervous EM and 13 cases of central nervous EM. The most frequently involved site was the sacral plexus (57%, n = 211), followed by the sciatic nerve (39%, n = 140). Other nerves were reported in significantly smaller numbers. Ninety seven percent (97%, n = 355) of peripheral nerve cases presented with pain, 20% (n = 72) reported weakness and 31% (n = 114), numbness. Thirty four percent (34%, n = 38) had solely intraneural EM of which 89% (n = 33) had no peritoneal EM (percentage based on available information). In the central nervous system, the conus medullaris and/or cauda equina constituted the majority of cases with 54% (n = 7). Apart from perineural spread, other discussed mechanisms include retrograde menstruation with peritoneal seeding, hematogenous and lymphogenous spread, stem cell implantation either hematogenously or via retrograde menstruation with subsequent EM differentiation, and coelomic or Mullerian duct metaplasia. We believe this literature review supports perineural spread as an alternate mechanism for EM of nerve, particularly the subgroup with intraneural EM and without peritoneal disease.

Summary This study was carried out to reveal the formation of the sacral plexus in the Eurasian Eagle Owls (Bubo bubo) and the nerves originating from this plexus. Five EEOs, three of them were male and two were female, were provided from Wildlife Rescue and Rehabilitation Center of Kafkas University and used as materials. Following the euthanizing of the animals, abdominal cavity was opened. The nerves of plexus sacrales were dissected and photographed. It was detected that the sacral plexus was formed by the ventral ramus of five synsacral nerves. Moreover, it was determined that the roots of the sacral plexus formed three trunks: the truncus cranialis, the truncus medius and the truncus caudalis in fossa renalis. The availability of the n. ischiofemoralis and the availability of n. parafibularis were detected in the EEOs. Five branches were specified as having segregated from the sacral plexus: the n. cutaneus femoralis caudalis, the mutual root of n. fibularis with n. tibialis (n. ischiadicus), the rami musculares, the n. coxalis caudalis and the ramus muscularis. It was observed that the sacral plexus was linked to the lumbar plexus by the n. furcalis, to the pudendus plexus via the n. bigeminus. Consequently, the anatomic structure of the EEO's sacral plexus, the participating synsacral nerves to plexus and the innervation areas of these nerves were revealed.

Background An objective of our work was to clarify variations in pudendal nerve formation, as well as their possible impact on the clinical picture. Method Bilateral pudendal nerve course and formation was studied on 20 adult cadavers. An anterior approach was used in 15 subjects, and both posterior and anterior approaches were used in five subjects. Results The prefixed type plexus formation was observed in eight cases (40%). In these cases, S1 and S2 roots contributed to the formation of the pudendal nerve. In the postfixed type, the S3 root was dominant in two cases (66.7%), and less the S4 root in one case (23.3%), albeit to a lesser degree. Most commonly, the S2 root participated in its formation in 17 cases (85%). The inferior rectal nerve penetrating the sacrospinous ligament was seen in one case, arising from the pudendal nerve before entering the pudendal canal in four cases. The dorsal nerve of the penis arose from the S1 root in two cases (10%). We observed it branching before entering the pudendal canal in 15 cases (75%), and it had divided in the pudendal canal in the other cases. For the posterior access, the pudendal nerve was localized 13.1 ± 0.72 cm medial to the greater trochanter, 8.1 ± 0.72 cm above the ischial tuberosity, at a depth of 6.4 ± 0.32 cm. Conclusions This description may be useful when carrying out a pudendal nerve block and during surgical procedures carried out in this anatomical region.

The pudendal nerve is a considerably large branch of the sacral plexus. There are many articles in the literature concerning the pudendal nerve in adults, but as far as we know, there is none on the branching pattern and variations in pudendal nerve anatomy in fetus. This study investigates the pudendal nerve trunking with respect to the piriformis muscle in 25 formalin-fixed fetuses (50 sides of pelves, 15 females, 10 males), ranging from 20 to 37 weeks of gestation. We investigate pudendal nerve trunking in four types: Type I-a is defined as single-trunk with the inferior rectal nerve branching proximal to the dorsal nerve of penis/clitoris (38%), Type I-b is also single-trunk with the dorsal nerve of penis/clitoris branching proximal to the inferior rectal nerve (24%), Type II is double-trunk with medial trunk as an inferior rectal nerve (34%), and Type III is triple-trunk (4%). We measured the average diameter of the main trunk of pudendal nerve in Type I-a and I-b groups to be 0.98 6 0.33 mm. We also measured the average length of the pudendal nerve trunks before the dorsal nerve of penis/clitoris branch to be 7.35 6 3.50 mm. There was no significant statistical difference in the average length, diameter, number of trunks, and pudendal nerve variations between male and female and also right and left sides of the pelves. This first and detailed fetal study of pudendal nerve trunking with respect to the piriformis muscle would be useful for educational anatomy dissections and anatomical landmark definitions for relevant clinical procedures. Clin. Anat. 21:691–695, 2008. V V C 2008 Wiley-Liss, Inc.

This retrospective review characterizes the electrodiagnostic (EDX) features and etiologies of sacral plexopathies (SPs) and discusses difficulties in their identification. The EDX findings of 171 clinically suspected SPs were reviewed using the following criteria: reduced/absent sensory nerve action potentials (SNAPs) of the sural or superficial peroneal nerve, denervation of plexus-innervated muscles, and the absence of paraspinal denervation. Sixty cases localized unequivocally to the sacral plexus. The majority were cancer-related, followed by traumatic, idiopathic, and iatrogenic causes. Final diagnoses in the remaining 111 cases were indeterminate. Lesions localized to either the plexus or L4-5, S1 roots in 52 cases, the plexus or sciatic nerve in 32 cases, and were equally compatible with an SP, sciatic neuropathy, or radiculopathy in 27 cases. Findings in the EDX evaluation of SPs are often complex and difficult to localize to a specific site due to multiple complicating factors. Frequently, SPs cannot be diagnosed definitively by EDX assessment alone.

Thirteen patients were retrospectively identified with the electrodiagnostic pattern of combined L5 radiculopathy by needle electrode examination, and abnormality of the superficial peroneal nerve (SPN) sensory nerve action potential (SNAP) amplitude. To have combined L5-derived sensory and motor axon loss, lesions must be localized at or distal to the L5 dorsal root ganglion (DRG), but also proximal to the sacral plexus. Six patients had evidence of an active intraspinal canal (ISC) lesion, 3 had diabetes, and 4 had nonspecific causes. The ISC localization in at least 6 of our cases is counter to the commonly held electrodiagnostic dogma that L5 radiculopathy spares the SPN SNAP, but recent anatomic studies confirm the ISC location of up to 40% of L5 DRG. Thus loss of the SPN SNAP does not exclude ISC lesions.

With 24 figures Summary The pelvic limb of the ostrich is innervated by the lumbar and sacral plexuses. The lumbar plexus gave rise to several nerves (N.s) including, N. coxalis cranialis, lateral and cranial femoral cutaneous N.s, N. femoralis, cranial, caudal and medial crural cutaneous N.s, and N. obturatorius. The remaining nerves emanated from the sacral plexus. The N. iliotibial, N. ischiofemoralis, N. iliofibularis, and N. coxae caudalis were distributed in the thigh, while the N. ischiadica, which terminated as the tibial and fibular N.s that innervated the leg and foot. The tibial N. gave rise to the parafibular N. then divided to form the Nn. suralis medialis and lateralis. The N. suralis medialis continued as the N. metatarsalis plantaris medialis. The parafibular N. continued as the N. plantaris lateralis, which terminated as the R. digitalis of the fourth digit. The fibular N. terminated as the superficial and deep fibular N.s. The superficial fibular N. continued as the N. metatarsalis dorsalis lateralis and divided into two digital N.s to the third and fourth digits. The deep fibular N. crossed the ankle joint and continued as the N. metatarsalis dorsalis medialis that continued as the R. digitalis of the third digit. In general, the innervation of the pelvic limb of the ostrich was similar to the pelvic limbs of several different species of domesticated birds, including the chicken. We discuss the few differences as well as appropriate sites to perform nerve blocks for the lateral and medial dorsal and the lateral plantar N.s.

A 42-year-old woman developed lower extremity weakness and sensory loss 1 year after external and intracavitary radiotherapy for Stage IB carcinoma of cervix. She has been followed for 5 years posttreatment, and the neurologic abnormalities have persisted, but no evidence of recurrent carcinoma has been found. We believe this to be a rare case of sacral plexus radiculopathy developing as a late complication after radiotherapy. Suggestions are made for improving the radiotherapy technique to prevent this complication in future cases.

Schwannomas are nerve sheath tumors that are most often benign in nature. These tumors rarely occur in the retroperitoneum, where they are found in 0.5 to 5% of cases. Presenting signs are varied and non-specific and accurate pre-operative diagnosis of the tumor is difficult despite the use of various imaging techniques. Schwannomas suspected as gynecologic masses have been reported, but there have been few reports of benign retroperitoneal schwannomas in pregnancy. We present a case of an asymptomatic 33-year old primigravida, found to have a pelvic mass during the 1st trimester ultrasound scan. On the basis of this incidental finding, she underwent magnetic resonance imaging; the diagnosis was a retroperitoneal tumor thought to arise from the sacral plexus, and expectant management followed. During the 3rd trimester there was worsening of symptoms, increased pain in the left flank region and pain on walking. She underwent another MRI; there was no progression of tumor growth. Ultrasound examination prior to delivery showed the tumor at the level of the cervix in the left presacral region. On palpation there was tenderness in this region, but no palpable mass. She underwent an uncomplicated Cesarean section in the 37th week of gestation. One month later she was admitted to the department of neurosurgery, and underwent surgery, with complete excision of the tumor that was found to be a benign schwannoma on pathology.

Eight patients with sciatic nerve and sacral plexus nerve sheath tumors, seen at Louisiana State University Medical Center in Shreveport, are presented. These cases illustrate the broad spectrum of pathology and modes of presentation of patients with nerve sheath tumors in this region. Patients can be divided into 4 groups. Group I includes subgluteal and/or thigh lesions with a well-defined mass on CT. Group II patients have neuroforaminal enlargement (defined by CT) and usually have radicular leg pain. Patients in group III have intrapelvic tumors with extension into the thigh. They usually have a poorly defined mass on CT. Group IV includes patients that have an intrapelvic mass (usually well defined) with radicular leg pain and/or mass effect. CT scanning proved to be the diagnostic procedure of choice. It delineated the location and extent of the tumor and thus was important in determining resectability. The variable course of these tumors is emphasized. A conservative nonoperative approach should be considered in asymptomatic and/or neurologically stable patients.

The fact that the inferior rectal nerve may have an independent origin from the sacral plexus is acknowledged in most current anatomy texts. That it may pierce the sacrospinous ligament well medial to the ischial spine is no longer mentioned. This variation which may occur in as many as 20% of the sides examined, could present a problem in pudendal block.