Overview

This study will evaluate the ability of trigger point injections completed immediately following a total knee arthroplasty decrease pain scores and opioid use compared to sham injections. Given the current state of opioid dependency in the United States there needs to be a more focused attempt at treating post-operative pain without use of opioids. Given the manipulation of soft tissue during a total knee arthroplasty there seems to be a high correlation with pain and myofascial pain syndrome. This study will include an experimental (trigger point injection) and control (sham injection) group who are all undergoing a total knee arthroplasty. This is a pilot study that will include a maximum of 100 total patients (although it is planned for the study to be much smaller with a planned 10-15 patients per group). The procedure that will be completed is a trigger point injection with use of 1% lidocaine without epinephrine along the distal aspect of the vastus medialis and lateralis, proximal aspect of the medial and lateral gastrocnemius muscle bellies. The sham injection will be completed by pressing the needle against the skin without injecting any fluid. There will be a "blind" between the patient and the needle with both arms of the study. These patients will be followed up on POD1, and during weeks 2 and 6 follow-up where they will be given questionnaires to assess pain (visual analogue scale) and opioid use, and asked to bring their opioid medications to the clinic to assess the morphine milligrams equivalent (MME).

Eligibility

Inclusion Criteria:

• Aged 45 years or older
• Planned to undergo primary total knee arthroplasty
• Able to speak, read, and understand English
• Willing to complete a study questionnaires
• Willing to bring in their medications to be counted
• DoD beneficiaries
• No allergy to lidocaine
• Not fearful of needles.

Exclusion Criteria:

• Chronic opioid users (daily use of prescribed opioids for at least 90 days)
• Diagnosed with Fibromyalgia
• Non-English speaking
• Unable to read English
• Unable to understand English
• Pregnant
• Allergy to lidocaine
• Not willing to complete study questionnaires
• Not willing to bring in their medications to be counted
• Not a DoD beneficiary
• Fearful of needles