BACKGROUND: Together with an increased interest in minimally invasive lateral transpsoas approach to the lumbar spine goes a demand for detailed anatomical descriptions of the lumbar plexus. Although definitions of safe zones and essential descriptions of topographical anatomy have been presented in several studies, the existing literature expects standard appearance of the neural structures. Therefore, the aim of this study was to investigate the variability of the extrapsoas portion of the lumbar plexus in regard to the lateral transpsoas approach.
METHODS: A total of 260 lumbar regions from embalmed cadavers were utilized in this study. The specimens were dissected as per protocol and all nerves from the lumbar plexus were morphologically evaluated.
RESULTS: The most common variation of the iliohypogastric and ilioinguinal nerves was fusion of these two nerves (9.6%). Nearly in the half of the cases (48.1%) the genitofemoral nerve left the psoas major muscle already divided into the femoral and genital branches. The lateral femoral cutaneous nerve was the least variable one as it resembled its normal morphology in 95.0% of cases. Regarding the variant origins of the femoral nerve, there was a low formation outside the psoas major muscle in 3.8% of cases. The obturator nerve was not variable at its emergence point but frequently branched (40.4%) before entering the obturator canal. In addition to the proper femoral and obturator nerves, accessory nerves were present in 12.3% and 9.2% of cases, respectively.
CONCLUSIONS: Nerves of the lumbar plexus frequently show atypical anatomy outside the psoas major muscle. The presented study provides a compendious information source of the possibly encountered neural variations during retroperitoneal access to different segments of the lumbar spine.

BACKGROUND: Chronic hip pain is one of the most common and difficult-to-treat causes of disability. Our study\'s primary aim was to investigate the effects of ultrasound and fluoroscopy-guided radiofrequency thermocoagulation of the femoral and obturator nerve articular branches on chronic hip pain, and the secondary aim was to determine its effects on hip function and quality of life.
METHODS: Fifty-three patients with hip pain lasting more than three months were enrolled in the study. VPS scale and WOMAC, SF-12 questionnaires were applied to the patients before and in the first, third, and sixth months following the procedure.
RESULTS: Of the patients, 60.4% were female, and 39.6% were male. Hip pain was caused by osteoarthritis in 77.1%, postoperative hip pain in 12.5%, malignancy in 8.3%, and avascular necrosis in 2.1%. The VPS scores were 8.9 ± 1.1 (mean±SD) in the baseline period, 2.4 ± 2.5 in the first postoperative week, 3.8 ± 2.5 in the first month, 5.1 ± 2.8 in the third month, and 5.8 ± 2.7 in the sixth month, with a significant decrease in VPS score (P < .001). One patient developed a motor deficit that improved spontaneously.
CONCLUSIONS: We concluded that radiofrequency thermocoagulation application to the articular branches of the femoral and obturator nerves provides pain relief, hip function improvement, and better quality of life (better physical component scores but no improvement in mental component scores in SF-12) for up to 6 months in chronic hip pain.

Background This study aimed to compare ultrasound versus ultrasound with nerve stimulation-guided obturator nerve block (ONB) for the prevention of adductor spasm in patients undergoing transurethral resection of bladder tumor (TURBT). Methodology This randomized controlled study included 240 adult patients in the age group of 30 to 70 years undergoing TURBT for lateral and posterolateral wall bladder tumors who fulfilled the American Society of Anesthesiologists grade I and II criteria. The patients were divided into two groups: group U (n = 120) included patients who underwent ONB using an ultrasound-guided technique and group UN (n = 120) included patients who underwent ONB using ultrasound with the nerve stimulation technique. Block performance time, adductor jerks/spasms, adductor muscle power, and patient and surgeon satisfaction were compared. A P-value <0.05 was considered statistically significant. Results The mean block performance time in group U was significantly less (4.4 ± 0.82 minutes) than in group UN (6.55 ± 0.37 minutes). Compared to group U, group UN had significantly fewer adductor jerks/spasms during the surgery (7.76% vs. 20.35%, p = 0.006), significantly more surgeon satisfaction (92.24% vs. 79.65%, p = 0.006), significantly more patient satisfaction (92.24% vs. 79.65%, p = 0.006), and comparable complications (excessive bleeding and minor bladder injury) and adductor muscle power after the block (p > 0.05). Conclusions ONB using the nerve stimulation technique under ultrasound guidance has a longer mean block performance time, a higher success rate, and higher surgeon satisfaction than ONB under ultrasound guidance only.

The objective of our study was to compare the efficacy of sciatic and saphenous ultrasound nerve blocks with and without US-guided obturator nerve block in dogs undergoing tibial-plateau-levelling-osteotomy (TPLO) surgery. This study was developed in two phases: identification of an ultrasound window in the inguinal region for obturator nerve block and utilization of it in dogs undergoing TPLO. Dogs were assigned randomly to one of two groups: one received the three blocks with 0.5% ropivacaine (ON group) and the second one (NoON group) with NaCl instead of ropivacaine for the obturator block. In phase 1, the obturator nerve was visible between the pectineus and the abductor muscles and was approached using an in-plane technique. It was possible to use the ultrasound window for phase two. The number of dogs that received at least one bolus of intraoperative rescue analgesia in the NoON group (12/15 dogs) was significantly higher (p = 0.003) in comparison with the ON group (4/15). An ultrasound window to block the obturator nerve in the inguinal compartment with an in-plane technique was found. The use of this approach could produce adequate analgesia with less motor function impairment in dogs for TPLO surgery.

BACKGROUND: Obturator nerve entrapment or idiopathic obturator neuralgia is an unfamiliar pathology for many physicians which can lead to diagnostic errancy. This study aims to identify the potential compression areas of the obturator nerve to improve therapeutic management.
METHODS: 18 anatomical dissections of lower limbs from 9 anatomical cadavers were performed. Endopelvic and exopelvic surgical approaches were utilized to study the anatomical variations of the nerve and to identify areas of entrapment.
RESULTS: On 7 limbs, the posterior branch of the obturator nerve passed through the external obturator muscle. A fascia between the adductor brevis and longus muscles was present in 9 of the 18 limbs. The anterior branch of the obturator nerve was highly adherent to the fascia in 6 cases. In 3 limbs, the medial femoral circumflex artery was in close connection with the posterior branch of the nerve.
CONCLUSIONS: Idiopathic obturator neuropathy remains a difficult diagnosis. Our cadaveric study did not allow us to formally identify one or more potential anatomical entrapment zones. However, it allowed the identification of zones at risk. A clinical study with staged analgesic blocks would be necessary to identify an anatomical area of compression and would allow targeted surgical neurolysis.

To compare the ability of the obturator nerve block (ONB) and increased plasma ignition distance practice (IPDP) techniques to inhibit obturator nerve reflex (ONR) occurring with bipolar transurethral resection of the bladder.
Sixty patients who had a tumor placed at the lateral sidewall or had a tumor in another part of the bladder along with the lateral wall were randomly enrolled. Cystoscopic and ultrasonographic examinations and a computerized tomography scanning of the urinary bladder were used to determine the ONB side. Group 1 consisted of patients who had the ONB procedure. Group 2 consisted of patients who had IPIDP. The severity of the ONR was classified as severe, mild, and very mild. The study\'s primary endpoint was ONR occurrences and successful completion of the surgery. The secondary endpoints were bleeding and bladder perforation.
There was a significant difference in the occurrence of ONR between the two groups (P = 0.0011). However, there was no significant difference between the two groups in the ability to resect the tumor and complete the surgery (P = .764). There was no correlation between the ONR and the tumor size (P = 0.478).
Our study concluded that both ONB and IPIDP have comparable results, especially in resecting tumors and completing the operation. IPIDP has some advantages over ONB, such as shorter operative time, lower total costs, and less trained personnel requirements.

BACKGROUND:  This cadaveric study aimed to describe the anatomy of the profunda artery perforators (PAPs).
METHODS:  In total, nine free cadavers with 18 upper thighs were dissected, 12 of which were from female cadavers, and 6 were from male cadavers. The average age of the cadavers was 84.7 ± 4.2 years. Dissection was performed to evaluate the anatomic position and characteristics of the femoral PAPs. The perforator distance from the gluteal sulcus, number of perforators, perforating muscles, diameter of the perforators, origin of the perforators, and number of nerves passing above and below the perforators were determined.
RESULTS:  The average number of perforators that penetrate the adductor magnus muscle was 2.5. The average distance from the origin of the perforators to the gluteal sulcus was 71.72 ± 28.23 mm. The average numbers of the obturator nerves passing above and below the perforator in the adductor magnus muscle were 1.3 (range, 0-4) and 0.7 (range, 0-2), respectively.
CONCLUSIONS:  The results provide a detailed anatomic basis for the PAP flap. The perforators of a PAP flap may be included in a flap with a transverse design. Sacrificing the small obturator nerves during dissection may not lead to significant donor site morbidity.

Anterior branch of the obturator nerve transfer has been proven as an effective method for femoral nerve injuries, but the patient still has difficulty in rising and squatting, up and downstairs. Here, we presented a novel neurotization procedure of selectively repairing 3 motor branches of the femoral nerve by transferring motor branches of the obturator nerve in the thigh level and assessing its anatomical feasibility.
Eight adult cadavers (16 thighs) were dissected. The nerve overlap distance between the gracilis branch and the rectus femoris (RF) branch, the adductor longus (AL) branch and the vastus medialis (VM) branch, as well as the adductor magnus (AM) branch and the vastus intermedius (VI) branch were measured. Also, the axon counts of the donor and recipient nerve were evaluated by histological evaluation.
In all specimens, nerve overlap of at least 2.1 cm was observed in all 16 dissected thighs between the donor and recipient nerve branches, and the repair appeared to be without tension. There is no significant difference in the axon counts between gracilis branch (598 ± 83) and the RF branch (709 ± 151). The axon counts of the AL branch (601 ± 93) was about half of axon counts of the VM branch (1423 ± 189), and the axon counts of AM branch (761 ± 110) was also about half of the VI branch (1649 ± 281).
This novel technique of the combined nerve transfers below the inguinal ligament, specifically the gracilis branch to the RF branch, the AL branch to the VM branch, and the AM branch to the VI branch, is anatomically feasible. It provides a promising alternative in the repair of femoral nerve injuries and an anatomical basis for the clinical application of motor branches of the obturator nerve transfer to repair the motor portion of the injured femoral nerve.

OBJECTIVE: Spasticity is the result of a variety of lesions to the central nervous system and one of the most common causes of disability worldwide. Selective peripheral neurectomy (SPN) is a surgical procedure that permanently decreases focal spasticity. The authors\' objective is to provide recommendations, in terms of probabilities, for locating terminal motor entry points to muscles of the thigh, as alternatives for proximal incision sites to SPN.
METHODS: The femoral, obturator, and sciatic nerves, and its corresponding motor rami, were systematically dissected on cadaveric specimens, and terminal motor entry points to each muscle of the thigh were located and carefully measured, relative to the length of the thigh. Measurement distributions were obtained and normal transformations were used when necessary.
RESULTS: In 23 adult cadaveric specimens, 779 motor rami were dissected. Entry points\' locations are presented as a percentage of the length of the thigh in means and standard deviations, which roughly corresponds to 64 and 95% probability of finding a motor entry point.
CONCLUSIONS: Alternative incisions directly over the motor entry points, for the muscles of the thigh, may be helpful when considering SPN as treatment for focal spasticity. A prior degree of certainty of the location of the nerve to be severed may simplify surgical approach.

Bladder dysfunction after nerve injury has a variable presentation, and extent of injury determines whether the bladder is spastic or atonic. The authors have proposed a series of 3 nerve transfers for functional innervation of the detrusor muscle and external urethral sphincter, along with sensory innervation to the genital dermatome. These transfers are applicable to only cases with low spinal segment injuries (sacral nerve root function is lost) and largely preserved lumbar function. Transfer of the posterior branch of the obturator nerve to the vesical branch of the pelvic nerve provides a feasible mechanism for patients to initiate detrusor contraction by thigh adduction. External urethra innervation (motor and sensory) may be accomplished by transfer of the vastus medialis nerve to the pudendal nerve. The sensory component of the pudendal nerve to the genitalia may be further enhanced by transfer of the saphenous nerve (sensory) to the pudendal nerve. The main limitations of coapting the nerve donors to their intrapelvic targets are the bifurcation or arborization points of the parent nerve. To ensure that the donor nerves had sufficient length and diameter, the authors sought to measure these parameters.
Twenty-six pelvic and anterior thigh regions were dissected in 13 female cadavers. After the graft and donor sites were clearly exposed and the branches identified, the donor nerves were cut at suitable distal sites and then moved into the pelvis for tensionless anastomosis. Diameters were measured with calipers.
The obturator nerve was bifurcated a mean ± SD (range) of 5.5 ± 1.7 (2.0-9.0) cm proximal to the entrance of the obturator foramen. In every cadaver, the authors were able to bring the posterior division of the obturator nerve to the vesical branch of the pelvic nerve (located internal to the ischial spine) in a tensionless manner with an excess obturator nerve length of 2.0 ± 1.2 (0.0-5.0) cm. The distance between the femoral nerve arborization and the anterior superior iliac spine was 9.3 ± 1.8 (6.5-15.0) cm, and the distance from the femoral arborization to the ischial spine was 12.9 ± 1.4 (10.0-16.0) cm. Diameters were similar between donor and recipient nerves.
The chosen donor nerves were long enough and of sufficient caliber for the proposed nerve transfers and tensionless anastomosis.