Spinal osteotomy in the presence of massive lumbar epidural scarring.

The combination of Massive epidural scarring and spinal deformity represents the ultimate challenge for the spinal deformity surgeon. This is observed more and more as the population is aging and the number of spine surgery is increasing. In assessing the patient with spinal deformity and epidural scarring, one should carry out a thorough medical work up including Dexa scan, comorbidities, and in most cases a Myelo-CT scan that will identify the extent of the previous fusion, the fixed or semi-rigid nature of the deformity with complete anterior fusion or only bone bridges, the evaluation of the previous instrumentation (if present) with possible screw misplacement, or halo around the screws, the extent of the previous laminectomy, the spinal stenosis and possible arachnoiditis and or meningocele. Once the requirement of deformity correction has been established with specific attention to the pelvic incidence and amount of lordosis required two basic choices can be made. The first one is to perform the spine realignment outside the massive epidural scarring whether this will be performed through simple posterior osteotomies, TLIF combined with Smith-Petersen osteotomies or Pedicle subtraction osteotomies. One should not forget about all the possibilities of an anterior or lateral approach to the spine that can also judiciously realign the spine at the level or at distance of the massive epidural scarring. These anterior realignments have to be supplemented with posterior fixation and or osteotomies. The other alternative is to perform the spine osteotomy at the level of the massive epidural scarring preferably at the junction of normal dura and epidural scar. Working around the dura that will require to be thinned down before the osteotomy is performed represents another challenge where incidental durotomies are not infrequent. During the closing of the osteotomy the dura may not be as giving as a normal dura and too aggressive closure of the osteotomy may not be possible. Instead a closing/opening osteotomy may be preferable, but will require an additional anterior column support. Attention to anterior column reconstruction and solid posterior instrumentation (iliac screws, four rods) should be given to all these revisions to have a long-lasting result.