Thoracic Disc Herniation
The patient is a 58-year-old Caucasian male who presented with a chief complaint of gait disturbance. The gait disturbance had been present for one year, but it had significantly deteriorated in the previous 2 months. The patient reported no pain, no bowel or bladder impairment, and no significant medical history.
The patient was obese, weighing 225 lbs and measuring 5'11". Motor strength in the lower extremities was normal. Hyper reflexia was apparent in the knees and ankles. A decrease in touch sensation was subjectively noted. Spinal alignment was normal.
The patient had not undergone any prior treatment.
Figure 1: Sagittal and axial pre-operative images showing T7-T8 herniation with cord compression
The patient was diagnosed with a disc herniation at T7-T8.
The patient underwent an XLIF with MIS discectomy and fusion.
Figure 2: Post-operative image after XLIF with MIS discectomy and fusion procedure
The patient had a significant improvement of gait disturbance, which the patient reported as being entirely satisfactory. Radiographs indicated a solid fusion. The patient is now 3 years post-op.
With the primary complaint of gait disturbance and hyperreflexia, this patient is a candidate for spinal cord decompression at the involved level. The choice of a lateral approach was successful in Dr. Yoon’s hands but may not be widely generalized to this disease.
The lateral retractors provide a perpendicular view to the lateral side of the spine. To safely approach and, more importantly, confirm spinal cord decompression, often a more oblique vantage point may be required. Coming in more anteriorly and visualizing the neural elements directly would provide a higher level of safety.
Either a formal thoracotomy or an endoscopically-assisted discectomy would provide this approach. Although fusion is more difficult endoscopically, it is unclear if fusion is primarily required in this disease process. If fusion was felt to be indicated, the more formal open procedure may be best.
Author's Concluding Comments
Due to the progressive symptoms and significant cord compression, decompression of the spinal cord is the most appropriate treatment. The surgical treatment strategy can vary depending on many factors, including the experience and preference of the surgeon. A laminectomy-only approach to remove the disc is probably not the best option, as it is very difficult to avoid putting the spinal cord at risk to remove the centrally-located disc.
An oblique (posterolateral) approach to this disc herniation is possible by a wide laminectomy and facetectomy and possibly costotransversectomy. This approach would necessitate a posterior fusion and entail significant morbidity.
An anterior approach with a traditional thoracotomy (rib resection) is a fairly standard option and can be used successfully. Finally, the method chosen by the author involved using XLIF retractor system to gain access to the disc without rib resectino or lung deflation. This allowed safe discectomy and more rapid recovery by the patient than would be possible through a standard thoracotomy.