Clinical Findings

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  A patient presented with pain in the right S1 dermatome having lasted for 4 months.

  
  
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  The VAS score was 9/10 for right leg pain and 3 to 4/10 for back pain.

  
  
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  A preoperative MRI showed a very large downward-migrated disk herniation at the L5-S1 level. A CT scan also showed a soft disk ( Fig. 18.112 ).

Preoperative Planning

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  First, for the paramedian disk herniation, an approach through the shoulder area is preferred ( Fig. 18.113A ).

  
  
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  Second, an axillary approach must be used for the downward-migrated disk fragment ( Fig. 18.113B,C ).

Surgical Procedures (Shoulder Approach)

1. 
   

   The shoulder area is identified with an epidurogram ( Fig. 18.114A,B ).

   
   
2. 
   

   After identification of the shoulder area, the needle is advanced into the annulus ( Fig. 18.114C,D ).

   
   
3. 
   

   The working channel is positioned under fluoroscopic guidance ( Fig. 18.114E,F ).