4.1.1 Principal Indications

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  Kyphosis

  
  
• 
  

  Tumors

  
  
• 
  

  Spondylitis

Generally, this approach to the lumbar spine can be made from the right as well as from the left side. Insofar as the side of the approach is not dictated by the underlying disease (e.g., the scoliotic component in thoracolumbar kyphosis, tumor extension, etc.), the left-sided approach is used.

4.1.2 Positioning and Incision

The patient is placed on the right side. If conditions warrant, the table may be tilted in the lumbar region, and a kidney rest may be applied. In this way, the distance between the costal arch and the iliac crest is increased. To stabilize the position, the patient′s right leg is flexed at the hip and knee, while the left leg remains relatively extended. To avoid pressure points, a cushion is placed between the two legs. Straps are used to secure the patient ( Fig. 4.1 ).

If an approach to L2 is needed, it is best to resect the 12th rib. An alternative is a subcostal flank incision. The skin incision begins near the midline at the level of the spinous process of T11, continues along the 12th rib, and then extends obliquely forward to the vicinity of the rectus sheath. Depending on the desired area of exposure, it may be extended caudad lateral to the rectus sheath.

Now the latissimus dorsi is dissected transversely to the direction of its fibers, and the external oblique is in part divided parallel to the direction of its fibers ( Fig. 4.2 ). On the next deeper plane, serratus posterior inferior is transected in the posterior region of the wound and, more anteriorly, the internal oblique together with the transversus abdominis ( Fig. 4.3 ).

Transection of the deep abdominal muscle layers provides access to the retroperitoneal space. The kidney and the ureter are retracted to the right. Now quadratus lumborum becomes visible ( Fig. 4.4 ). At this point, the intrinsic back muscles are divided at the level of the 12th rib as indicated by the dashed line, the periosteum over the 12th rib is incised, and the peripheral portion of the rib is resected ( Fig. 4.5 ). Opening of the pleural cavity is thus avoided ( Fig. 4.6 ; see also Fig. 3.26). Subsequently, the periosteum of the rib bed is split in the middle, and the cranial half is retracted upward together with the diaphragm that is attached here. Care should be taken to preserve the 11th and 12th intercostal nerves (subcostal nerve). Finally, a thoracic retractor is applied ( Fig. 4.7 ). Fig. 4.8 presents the anatomical site.

4.1.3 Exposure of the Vertebrae

The retroperitoneal tissue overlying the lumbar spine is split longitudinally, the sympathetic trunk being left laterally. The segmental vessels are exposed in customary fashion and are transected in the midline if possible. Vertebral bodies and intervertebral disks are then accessible over the entire circumference ( Fig. 4.9 ).

4.1.4 Wound Closure

To begin with, the bed of the 12th rib is sutured in the peripheral area. Further wound closure is effected in layers, largely in conformity with the procedure used for the extrapleural retroperitoneal approach according to Mirbaha (see Section 3.3.4, Fig. 3.32).

4.2.1 Principal Indications

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  Spondylolisthesis

  
  
• 
  

  Presacral osteochondrosis

  
  
• 
  

  Tumors

4.2.2 Positioning and Incision

The patient is placed supine with a bolster under the lumbar spine. The operating table is angulated in the middle, producing a hyperlordosis that facilitates the approach to the promontory. Lowering of the legs at the same time reduces venous reflux.

A midline laparotomy curving to the left of the umbilicus is performed in the usual manner ( Fig. 4.10 ). The skin incision begins two to three fingerbreadths above the umbilicus and ends three fingerbreadths above the symphysis. Following dissection of the subcutaneous tissue, the linea alba is exposed and divided in the midline with a scalpel. The subjacent peritoneum is now lifted with two forceps, incised with a scalpel, and then split longitudinally with scissors ( Figs. 4.11 and 4.12 ).