Lateral sacral

The uterine blood supply is primarily from the uterine arteries. The uterine arteries arise as branches of the internal iliac (hypogastric) arteries. In most cases, the internal iliac artery divides into a posterior division that gives off the iliolumbar, the lateral sacral and the superior gluteal arteries and an anterior division that gives rise to parietal branches (the obturator, inferior gluteal and internal puden-... 

Occasionally, communications between various branches of the IIA and the lumbar arteries may cause retrograde flow into the sac of an aortic aneurysm creating a type-II endoleak. Microcatheter traversal of the entire length of these conununications may not always be possible. Under such circumstances, liquid embolic agents have been employed to occlude the feeder arteries. As mentioned above, this practice may cause ischemic radiculopathy if the targeted vessels are either lateral sacral or iliolumbar arteries. It may be more prudent to coil embo-lize these arteries and use alternative approaches to deal with the possible residual type-II endoleak (see Chap. 14). 

Embolization of the IIA or its branches (lumbosacral or lateral sacral arteries) may cause ischemia of the lumbosacral nerve roots. The pain associated with this condition resembles nerve root compression and can be mistaken for buttock and thigh claudication. The pain and discomfort is usually more intense, lasts longer, and may be associated with ipsilateral weakness. This condition can be precipitated by unilateral IIA embolization and should be considered in patients with persistent symptoms. 

Access to either the contralateral or ipsilateral internal iliac arteries can be facilitated using a Wait-man s loop technique with a Cobra 2 catheter alternatively, a long reverse curve catheter can be used. Care must be taken not to catheterize too distally so as to ensure visualization of the lateral sacral and iliolumbar arteries [50]. Carbon dioxide offers an alternative contrast agent that has the benefits of no allergic reactions, nephrotoxicity, or volume limitations, low cost and flexibility of use with different sized catheters [51-53]. High-pressure contrast injections should be avoided since they may potentially dislodge newly formed clots and result in loss of hemostasis [54]. 

Epidural anesthesia is administered by injecting local anesthetic into the epidural space (the space bounded by the ligamentum flavum) posteriorly, the spinal periosteum laterally, and dura anteriorly. Epidural anesthesia can be performed in the sacral hiatus (caudal anesthesia) or in the lumbar, thoracic, or cervical regions of the spine. 

Epidural anesthesia is administered by injecting local anesthetic into the epidural space—the space bounded by the ligamentumflavum posteriorly, the spinal periosteum laterally, and the dura anteriorly. Epidural anesthesia can be performed in the sacral hiatus (caudal anesthesia) or in the lumbar, thoracic, or cervical regions of the spine. Its current popularity arises from the development of catheters that can be placed into the epidural space, allowing either continuous infusions or repeated bolus administration of local anesthetics. The primary site of action of epidurally administered local anesthetics is on the spinal nerve roots. However, epidurally administered local anesthetics also may act on the spinal cord and on the paravertebral nerves. 

Three channels for bilateral sacral root stimulation (S2-4) for bladder control (bowel control and erection, if possible) were provided. Sacral root stimulation was achieved by three pairs of LPR electrodes (10-mm long, solid platinum tubing of 1.0-mm diameter) inserted into the external sacral foramina in a lateral direction to follow and to stimulate the nerve roots epidurally. One further channel was connected to an epidural spinal cord stimulating electrode (Pisces Quad Medtronic Inc., Minneapolis, MN) for conus medullaris modulation of spastic bladder and bowel reflexes. 

Posterior tumor growth leads to infiltration of the presacral space and sacral bone or of the perirectal space and rectum. Recurrent cervical cancer is associated with rectal infiltration in about 17% of cases. The most common site is the rectosigmoid junction. Laterally, recurrent tumor may extend to the pelvic sidewall. If the recurrent local tumor grows anteriorly along the peritoneal fold, there will be infiltration of the urinary bladder. Advanced recurrent cervical cancer may involve the remaining colon or the small intestine and is typically associated with adhesion of bowel loops and may cause intestinal obstruction. 

Michaelis s rhomboid is the rectangular area over the sacral bone formed by the dimple below the spinal processes of L3 to L4 (upper depression), the two posterior spines of the ilia (lateral depressions), and the groove at the distal end of the vertebral column (lower depression). The rhomboid is usually a square while its height increases considerably relative to its width in women with general narrowing of the pelvis. The lateral dimples are elevated in women with an android pelvis. 

More frequently, elongation or rupture of the isthmic part avoids any posterior compression root compression is at the apex of lumbo-sacral kyphosis and mainly lateral in the foramen between the bulging disc, the isthmic area and decreased distance between the pedicle of L5 and the superior part of SI. There is a combination of vertical narrowing laterally and local kyphosis medially. 

Without distraction, the L5 vertebral body just rolls over the sacral dome. The instrumented postero-lateral fusion moved close to the vertical gravity line, with subsequently less stress. It is strong enough to maintain the correction without anterior fusion. 

Fig. 13. Spondyloptosis with changes in the positional and spinal parameters. Reduction of spondyloptosis with improvement of the positional and spinal parameters. One year after surgery further improvement of the parameters with normalization of the projection of the gravity line. Three years later unchanged positional parameters of the lumbo-sacral hinge, but further alignment at the spinal parameters with complete normalization of the course of the gravity line...

Pelvis an anterior, lateral, or posterior approaches (avoiding the femoral and sacral nerve plexus and the sacral canal) are used. 

The spinal cord ends at about the level of the second lumhar vertebra. Lower nerve roots run caudally and laterally to exit from the intervertebral foramina. This termination of the cord into a spray of nerve roots is known as the cauda equina. Disk herniation disturbs the nerve root of the lower of the vertebrae involved. Therefore, an L5-S1 herniated disk will cause dysfunction of the first sacral nerve root. 

Dysplastic spondylolisthesis is a congenital abnormality most typically of the first sacral or fifth lumbar neural arch. This defect generally becomes apparent during childhood or adolescence. This can be diagnosed on lateral view x-rays of the lumbar spine. 

During these motions, the lumbar spine rotates to the right and flexes laterally to the left, compensating for the right sacral flexion created by pelvic rotation toward the left with right pelvic tilt The relationship of the rotated right L5 to the left-on-left sacral rotation completes the picture... 

Unilateral erector spinae contraction will cause lateral flexion to the side of contraction, scoliosis with convexity to the opposite side, and extension of the spine. The patient walks with a stiff back, with no lumbar rotation or flexion. The spinal areas involved are usually at the fourth or flfth lumbar and first sacral segments. An acute anterior sacrum dysfunction on the same side may also be present. If findings include a raised iliac crest height, lumbar scoliotic convexity, and sciatic pain distribution, all on the same side, the prognosis for a speedy recovery is often good. If the pain is on the other side, the cause may be a prolapsed disk or some other serious pathologic condition, and both physician and patient may be in for a difficult time. 

Note Because of sacral structure and the types of movement available, the inferior lateral angles exhibit pairing in these positions poste-rior/inferior and anterior/superior are coupled positions. 

Bilateral sacral flexions and extensions are not as common as the other findings. The report of symptoms in the apparent absence of positive tests of laterality and asymmetry may be more indicative. Observation of the decrease of movement with respiration and clinical experience may be the best indications as to the presence of these bilateral diagnoses. 

This tender point is palpated by pushing the monitoring finger medially on the lateral edge of the sacrum at the midpoint between the posterior superior iliac spine (PSIS) and the sacral apex. This is at the site of the piriformis attachment to the sacrum and probably represents a second piriformis tender point, it is often found in association with the tender point in the belly of the muscle. 

The lateral rotator muscles of the hip include the piriformis and the obturator internus. The piriformis muscle has its medial attachment to the lateral border of the sacrum and is often involved in sacral dysfunctions. 

Clinically, a hypertonic piriformis is correlated with a posterior inferior lateral angle [11-A] on the same side. The muscle could be significant in causing or maintaining sacral somatic dysfunctions. 

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