Lateral Branch Blocks
About Lateral Branch Blocks for Sacroiliac Joint Pain Diagnosis
Lateral branch blocks are diagnostic injections used to help determine whether the sacroiliac (SI) joint is the source of a patient's lower back, buttock, hip, or leg pain.
The lateral branch nerves are small sensory nerves that carry pain signals from the sacroiliac joint to the brain. During a lateral branch block, a local anesthetic is carefully injected near these nerves to temporarily interrupt pain signals.
If significant pain relief is experienced following the procedure, the sacroiliac joint is likely contributing to the patient's symptoms. This information can help guide future treatment options, including radiofrequency ablation for longer-lasting pain relief.
Lateral branch block FAQ's
What is the purpose of a lateral branch block?
A lateral branch block is primarily used to diagnose sacroiliac joint-related pain. By temporarily numbing the nerves that supply sensation to the SI joint, physicians can determine whether those nerves are responsible for the patient's symptoms.
The procedure may also provide temporary pain relief, but its primary purpose is to help identify the source of pain and determine whether additional treatments may be beneficial.
How is a lateral branch block performed?
During the procedure, the patient is positioned comfortably while the treatment area is cleaned and prepared. Using fluoroscopic (X-ray) guidance, the physician carefully places small needles near the lateral branch nerves surrounding the sacroiliac joint.
A local anesthetic is then injected around the targeted nerves. The procedure is typically completed in a short outpatient visit, and patients are often able to return home the same day.
How do physicians determine whether the block was successful?
After the procedure, patients are asked to monitor their pain levels and perform activities that would normally trigger their symptoms.
If significant temporary pain relief is experienced during the expected duration of the anesthetic, the results suggest that the sacroiliac joint and its associated nerves are contributing to the pain. These findings help physicians confirm a diagnosis and develop an appropriate treatment plan.
Can a lateral branch block help determine if I am a candidate for radiofrequency ablation?
Yes. One of the primary reasons lateral branch blocks are performed is to evaluate whether a patient may benefit from radiofrequency ablation (RFA).
If the diagnostic block significantly reduces pain, radiofrequency ablation may be recommended to disrupt the targeted nerves for a longer period of time. Many patients experience longer-lasting relief following RFA compared to diagnostic injections alone.
What is the difference between a sacroiliac joint injection and a lateral branch block?
Although both procedures are used to evaluate and treat sacroiliac joint pain, they target different structures.
A sacroiliac joint injection places medication directly into the SI joint and may be used for both diagnosis and treatment. A lateral branch block targets the nerves that transmit pain signals from the joint and is commonly used to determine whether radiofrequency ablation may be an effective treatment option.
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