Review Question - QID 215634

The patient suffers from a far lateral disc herniation and failure of conservative measures. This would best be approached with a lateral paraspinal (Wiltse) approach with partial discectomy.

Far lateral disc herniations are best approached with the lateral paraspinal (Wiltse) approach. This type of disc herniation affects the exiting nerve root (i.e. L3 nerve root affected at the L3-4 disc level). It is much less common compared to a paracentral disc herniation and can often present with more pain than expected due to compression of the dorsal root ganglion. Similar to the other types of disc herniations, a majority of far lateral herniations resolve with nonsurgical interventions such as physical therapy, nonsteroidal anti-inflammatories, steroid injections, and lifestyle modifications. For those that do require surgery, however, the typical midline approach will not provide adequate visualization and access to the disc for appropriate diskectomy.

Wiltse et al first described this approach in 1968 for the use of one-level fusions in young patients with spondylolisthesis. Briefly, the approach was described as being bilateral with hockey stick-shaped incisions about two fingerbreadths lateral to the midline. dissection is then completed through the paraspinal musculature for access to the facet joint and transverse process. They did use it on several occasions for disc removal, but this was not the intended use early on.

Marquardt et al followed patients with far lateral disc herniations treated via lateral paraspinal approach for over 12 years and reported on both short and long-term outcomes. In the short-term leg pain and low back pain decreased from 99.3 to 5.1% and 97.8 to 2.8% of patients, respectively. At over 12 years after surgical intervention, 75.9% of patients reported excellent relief, 18.4% good, 4.6% fair, and 1.1% poor, with the authors concluding that this approach is safe and provides good to excellent results in a vast majority of patients.

Figure A shows an axial T1 weighted MRI of the lumbar spine at the L3-4 interspace with a far lateral disc herniation. Figure B is a sagittal T1 weighted MRI showing a disc herniation filling up the foramen with loss of the typical appearance of the exiting nerve root with surrounding perineural fat.

Incorrect Answers:
Answer 1: This patient has failed nonsurgical management, so continued physical therapy is inappropriate.
Answer 3: This patient does not demonstrate instability as there is no effusion of the facet on the axial MRI and no obvious evidence of spondylolisthesis on the sagittal MRI.
Answer 4 & 5: A midline approach would not allow for adequate access to a foraminal/far lateral disc herniation.