Investigating the Minimum Number of Needling Required to Optimize Trigger Point Injections Outcome

Chronic pain affects over 100 million Americans with an annual cost of about $600 billion/year. Almost half of the chronic pain conditions are attributed to musculoskeletal conditions.

Musculoskeletal pain is typically identified with palpation over tender areas initially identified by the patient and then verified by the physician. There are typically areas of muscles that when palpated, pain is experienced by the patient. These points are known as Trigger Points. There are several ways to manage trigger points. Muscle relaxers are the most common pharmacological approaches to manage trigger points, but they can cause significant sedation for patients. Some non-pharmacological methods such as physical therapy may also provide some relief of musculoskeletal pain. However, physical therapy requires active participation from patients in addition to lifestyle modifications. Additionally, for some patients, the severity of their musculoskeletal pain precludes them from effectively participating in physical therapy. For those patients, trigger point injections may provide enough relief to effectively participate in physical therapy. Trigger point injections is a procedure where an area identified is first injected with a local anesthetic then the needle is repeatedly inserted in and out (needling). The exact mechanism of action is not clear, but it does provide significant relief for most patients with musculoskeletal pain. Interestingly enough, while trigger point injections are a very common procedure and are performed by almost all pain physicians, there is great variability in the method it is performed. There is currently no clear guidance as to how light or intense the "needling" aspect of the procedure should be. On one end of the spectrum, some pain physicians perform 1-2 needle passes. On the opposite end of the spectrum, other pain physicians perform 40-50 or more needle passes. The literature is not very clear as to which is better in terms of the number of passes. In fact, the range of passes from one study to the other may account for some inconsistencies of the outcome associated with performing trigger point injections. The greater the number of passes, the greater the risk for possible side effects. On the other hand, pain relief may be directly proportional to the number of passes. The investigators currently do not have such information. The purpose of this study is to understand the relationship between the intensity of the needling aspect of trigger point injections and pain relief. In this study, patients will undergo the typical standard of care treatment for musculoskeletal pain with randomization regarding the number of passes during needling. The investigators will evaluate the patient response using paper surveys over 2 months following their procedures.

Inclusion criteria

• Able to speak, read and write English
• Diagnosis of myofascial pain
• Failed conservative therapy or unable to participate in physical therapy

Exclusion criteria

• Serious mental illness that may not enable the patient to perceive pain changes
• History of conditions which may present as diffuse pain