Percutaneous disc decompression (PDD) is a minimally invasive procedure performed under fluoroscopic guidance for the treatment of lower back with or without radiation to the lower extremities secondary to a lumbar herniated nucleus propulsus. There are many different techniques described for performing PDD. These include chemonucleolysis using chymopapain, automated percutaneous lumbar decompression (APLD) using a nucleotome, percutaneous discectomy, laser discectomy, nucleoplasty, and dekompressor.1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 The primary goal of all of these procedures is to reduce pressure in the disc and remove disc material.
This chapter will discuss PDD using either the Stryker Disc Dekompressor (Figure 32-1) or the ArthroCare Nucleoplasty devices (Figure 32-2). Stryker’s Dekompressor mechanically aspirates disc material. As a result, aspirated disc material can be visually seen and sent for histological examination. ArthroCare’s Nucleoplasty uses Coblation, which uses bipolar radiofrequency energy to generate a plasma field that disintegrates disc material into gases that escape through the needle.
Both procedures are designed to reduce the size of a disc herniation thereby taking pressure off the affected nerve roots. This treatment modality is not considered a first-line therapy and should be considered only after a patient has failed more conservative therapies such as physical therapy, oral anti inflammatory medication, and epidural steroid injections.
Patient selection criteria for treatment with percutaneous disc decompression include:13
Axial back pain with or without radicular symptoms
MRI consistent with a contained disc herniation
Imaging demonstrating greater than 50% preserved disc height
Failed conservative treatment
Positive diagnostic selective nerve root block
Discography positive for concordant pain and post-discography CT scan consistent with a contained disc herniation (this is a relative criteria and depends on surgeon preference)
A standard percutaneous posterolateral discography approach to the disc is utilized. The Scottie dog image is utilized for initial approach to the disc space (Figure 32-3).
In order to minimize the risk of nerve root injury the needle is introduced in the safe triangle described by Kambin.
It is essential to confirm that the patient has a contained disc herniation (Figures 32-4 and 32-5). This is probably the most important thing to keep in mind to ensure success with these procedures. If the targeted disc does not have an intact annulus, the procedure is unlikely to be successful.
Types of disc herniation.