Q: What are spinal synovial cysts, and how are they treated?
A: Synovial cysts are cysts in the spine that are caused by a buildup of fluid from nearby a facet joint due to arthritis in the back.
When the cyst starts to grow, it can put pressure on a nearby nerve. Symptoms can be very similar to sciatica or spinal stenosis: lower back pain, leg pain or even leg weakness. Treatment options include both surgical and non-surgical methods. Our treatment plan depends on the cyst’s size, position, and the patient’s symptoms.
Non-surgical treatments include therapy, medications, and steroid injections with aspiration (drainage). If the pain is just in the back, we might first try a steroid injection or nerve block. If the pain is in the leg and back, we might do an epidural steroid injection combined with a facet joint aspiration or injection. We try to fill up the cyst with enough medication to pressurize it and ultimately rupture it. Cyst rupture is somewhat painful compared to injection only, but it is usually more effective long-term. I do remind patients that spinal cysts often grow back. However, many patients choose to go through with a minimally invasive procedure rather than having spine surgery.
Some patients don’t respond to these minimally invasive procedures and require surgery. The two most common surgeries for a spinal cyst are a decompression/cyst resection or a decompression cyst resection with a spinal fusion. With a decompression cyst resection, we remove the cyst (resection), relieving the pressure from the nerve root. As with disc herniation surgery, the success rate is quite high with this operation. Most patients do not need a fusion when we remove the cyst. But if there is some instability associated with the cyst or if the spine is unstable, a fusion is indicated. (Spinal fusion is surgery to permanently connect two or more vertebrae in your spine, eliminating motion between them.)
— Mike Mizrahi, interventional spine and musculoskeletal medicine specialist
This question was answered during the episode of Spine Time called “Back Pain: When Is Surgery the Answer (and When Isn’t It)?” A recording of this webinar held on June 20, 2020, is available on YouTube. (See the whole playlist here.)
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