Constant existence of the sensory branch of the nerve to the pyramidalis distributing to the upper margin of the pubic ramus.

Twenty-one sides of 11 adult Japanese cadavers were investigated, and 2 of 21 sides exhibited absence of the pyramidalis. We observed that all of the nerves to the pyramidalis included the sensory nerve branch, which distributed to the aponeurotic tissue in the upper area of the pubic ramus. To investigate the clinical relevance and developmental process of the pyramidalis, detailed innervation patterns of the pyramidalis and the lumber plexus were examined and compared with the case of absent pyramidalis. The nerves to the pyramidalis could be classified into five types by the derivative nerves and two subtypes by their courses associated with the funiculus spermaticus. In the cases of absent pyramidalis, similar sensory branches distributed close to the upper area of the pubic ramus. We deduced that the sensory branch extended along with the muscular branch to the pyramidalis after development of the pyramidalis and that only the sensory branch remained in cases in which the pyramidalis disappeared. The two subtypes might associate with descensus testis. Surgeons performing inguinal hernia repair using a mesh and tension-free surgical technique should preserve the nerves around the funiculus spermaticus to avoid diminished proprioception in the lower abdominal wall.

Minimally invasive treatment of unstable pelvic ring injuries with modified pedicle screw-rod fixator.

Objective To evaluate the clinical application of the minimally invasive modified pedicle screw-rod fixator for unstable pelvic ring injuries, including its feasibility, merits, and limitations. Methods Twenty-three patients (13 males, 10 females; average age, 36.3 years) with unstable pelvic ring injuries underwent anterior fixation using a modified pedicle screw-rod fixator with or without posterior fixation using a transiliac internal fixator. The clinical findings were assessed using Majeed scores. The quality of reduction was evaluated using the Matta criteria. Results Clinical results at 1 year postoperatively were excellent in 14 patients, good in 7, and fair in 2. The two patients with fair results had intermittent pain at the sacroiliac joint because of the posterior implant. One woman complained of persistent pain at the pubic tubercle during sexual intercourse. Iatrogenic neuropraxia of the unilateral lateral femoral cutaneous nerve occurred in three patients. Unilateral femoral nerve palsy occurred in one patient. The quality of fracture reduction was excellent in 12 patients, good in 8, and fair in 3. Heterotopic ossification occurred in eight patients; all were asymptomatic. Conclusions Minimally invasive modified pedicle screw-rod fixation is an effective alternative treatment for pelvic ring injuries.

[Effect of the anterior aspect of sacral nerve root tunnel on iliosacral screw placement on the standard lateral image of sacrum].

OBJECTIVE: To introduce the location and course of S1, S2 sacral nerve root tunnel and to clarify the significance of the anterior aspect of sacral nerve root tunnel on placement of iliosacral screw on the standard lateral sacral view. METHODS: Firstly the data of 2.0 mm slice pelvic axial CT images were imported into Mimics 10.0, and the sacrum, innominate bones, and sacral nerve root tunnels were reconstructed into 3D views respectively, which were rotated to the standard lateral sacral views, pelvic outlet and inlet views. Then the location and course of the S1, S2 sacral nerve root tunnel on each view were observed. RESULTS: The sacral nerve root tunnel started from the cranial end and anterior aspect of the vertebral canal of the same segment and ended up to the anterior sacral foramen with a direction from cranial-posterior-medial to caudal-anterior-lateral. The tunnel had a lower density than the iliac cortex and greater sciatic notch on the pelvic X-rays,especially on the standard sacral lateral view, on which it showed up as a disrupted are line and required more careful recognition. CONCLUSION: It can prevent the iliosacral screw from penetrating the sacral nerve root tunnel and vertebral canal when recognizing the anterior aspect of sacral nerve root tunnel and choosing it as the caudal-posterior boundary of the "safe zone" on the standard lateral sacral view.

Navigation-aided visualization of lumbosacral nerves for anterior sacroiliac plate fixation: a case report.

BACKGROUND: Anterior sacroiliac joint plate fixation for unstable pelvic ring fractures avoids soft tissue problems in the buttocks; however, the lumbosacral nerves lie in close proximity to the sacroiliac joint and may be injured during the procedure. METHODS: A 49 year-old woman with a type C pelvic ring fracture was treated with an anterior sacroiliac plate using a computed tomography (CT)-three-dimensional (3D)-fluoroscopy matching navigation system, which visualized the lumbosacral nerves as well as the iliac and sacral bones. We used a flat panel detector 3D C-arm, which made it possible to superimpose our preoperative CT-based plan on the intra-operative 3D-fluoroscopic images. RESULTS: No postoperative complications were noted. CONCLUSIONS: Intra-operative lumbosacral nerve visualization using computer navigation was useful to recognize the 'at-risk' area for nerve injury during anterior sacroiliac plate fixation.

The innervation of canine hip joint capsule: an anatomic study.

To clarify the contributions of the nerves supplying the canine hip joint capsule for clinical application, cadaver study of six healthy mongrel dogs was performed. The pelvises and hindlimbs of cadavers were dissected and fixed in formaldehyde. Innervation of the joint capsule was investigated with the aid of an operative microscope. As a result, the canine hip joint capsule receives multiple innervations from articular branches of four nerves. They are articular nerve fibres of femoral, obturator, cranial gluteal and sciatic nerves from the cranioventral, caudoventral, craniolateral and dorsolateral directions of the joint, respectively. No branch originating from the caudal gluteal nerve was observed innervating the hip joint capsule. Our data provides useful information for research on the canine hip joint, including pain analysis with hip disorders and surgical nerve blockade to relieve pain.

[Follow-up and prognosis of neurologic sequelae of pelvic ring fractures with involvement of the sacrum and/or the iliosacral joint]. / Verlauf und Prognose von neurologischen Ausfällen nach Beckenringfrakturen mit Beteiligung des Os sacrum und/oder Iliosakralgelenks.

The extent of neurological lesions following an injury of the pelvic ring is often not initially recognized, as interest is then focused on the treatment of the pelvic ring fracture. Once the fracture has healed, the patient suffers from the sequelae of the neurological injury. Our series of 323 pelvic ring injuries includes 161 sacral fractures and 12 complete disruptions of the sacroiliac joint. Twenty-three patients sustained an injury of the lumbosacral plexus, and 20 patients were examined retrospectively. The different parts of the lumbosacral plexus showed variable recovery potential. An important or complete recovery was noted in 8 of 9 patients suffering from a motor deficit of the lumbar plexus, the obturator nerve, the superior gluteal nerve or the inferior gluteal nerve. Four out of 8 patients with a motor deficit of the sacral plexus had an important or complete improvement. In contrast to these results was the poor recovery of lesions of the lumbosacral trunk. Eight out of 11 patients showed no or only minor recovery, although the pelvic ring was stabilized by operative means in 9 patients. In 2 patients the lumbosacral trunk was directly decompressed by a dorsal approach. In both cases the recovery was complete. In 6 patients the sphincter function was damaged. Recovery was dependent on the localization of the sacral fracture. If the fracture traversed the sacral canal, no neurological improvement was noted.

[Development and topography of the ganglion pelvinum in the gerbil]. / Asubildung und Topographie des Ganglion pelvinum beim Gerbil.

In the gerbil the nerve cells of the plexus pelvinus are concentrated on each side in a solid glanglion pelvinum. This deviates essentially from the pattern in man and the domestic animals where these cells are scattered all over the plexus pelvinus. The large ganglion pelvinum is connected craniodorsally with the nervus hypogastricus and dorsally with the nervi pelvini (from the first 2 or 3 sacral nerves and the last lumbar nerve). The apertura pelvis cranialis appears long and very oblique and, therefore, in the gerbil the ganglion pelvinum is located on each side cranially to the corpus ossis pubis and can be reached by a ventral laparotomy.