Epidural Lysis of Adhesions: What Every Interventional Pain Physician Needs to Know.

Background: Epidural lysis of adhesions is an effective therapy for treating refractory axial or radicular cervical, thoracic, or lumbar pain. This therapy is an important alternative to surgical interventions. As such, epidural lysis of adhesions is a significant addition to the techniques available to pain management physicians.

Rationale for lysis of adhesions: The underlying rationale for epidural lysis of adhesions is that nerves can become inflamed, either by being entrapped by epidural scarring or being compressed by veins engorged by epidural scarring. Furthermore, the posterior longitudinal ligament can become adhered to the dura. The goal of adhesiolysis, therefore, is to relieve the effects of this scarring. The dural tag is a helpful technique for diagnosing the condition clinically.

Mode of action: Epidural lysis of adhesions involves placing a spring-wound catheter into the tissue planes that entrap the nerve or vein, executing an injection protocol to expand that tissue plane, and then having the patient implement a self-directed home exercise program of neural flossing. The catheter should be placed in the ventrolateral epidural space, the site of pathology.

Technique: The injection protocol involves the use of contrast dye to confirm appropriate catheter placement. Hyaluronidase is used to enhance the flow of the medications through the tissue plane. Local anesthesia and steroids are given both for the analgesic and anti-inflammatory effects and because of corticosteroid's ability to inhibit fibroblast proliferation after the procedure. Hypertonic saline assists both with helping reduce swelling of the nerve and to provide hydrostatic force as it is diluted from 10% to 0.9% saline. Additionally, hypertonic saline causes an important, transient local anesthetic effect and a prolonged C-fiber blockade. The L5-S1 scarring triangle is an important, specific site of scarring that is now commonly treated, often in conjunction with transforaminal catheters, when performing adhesiolysis. It is imperative that patients meet appropriate discharge criteria before being discharged.

Complications: Complications are generally similar to those seen with other interventional procedures. For lysis of adhesions, the potential procedure-specific concern is the risk of subarachnoid spread of hypertonic saline. Although Hitchcock intentionally injected hypertonic saline into cancer patients intrathecally and observed limited adverse effects, epidural lysis of adhesions is specifically designed to minimize this risk by injecting a local anesthetic solution that will not cause motor weakness if injected epidurally but will cause motor weakness if it spreads to the intrathecal space. Perivenous counter spread is a rare complication that can be treated with flexion rotation procedures.

Controversies: The technique has engendered many controversies, including discussions relating to the amount of force generated. These controversies have influenced the adaptation of the procedure.

Evidence: Epidural lysis of adhesions has been studied extensively. Gerdesmeyer's randomized placebo-controlled trial with 10-year follow-up provides Level I evidence. This trial is supported by a significant number of other studies.

Conclusions: Epidural lysis of adhesions is an effective therapy for treating refractory axial or radicular pain. The technique provided is based upon experience with hundreds of thousands of patients. When performed by a trained physician, adhesiolysis is safe and effective.