The main objective of the trial is to compare the effectiveness of injected levobupivacaine and liposomal bupivacaine in the treatment of pain and disability in patients with lateral epicondylitis.

Primary outcome is pain (VAS) at 1 week and at 1 month after injection. Secondary outcomes are the Quick Disabilities of the Arm, Shoulder and Hand DASH (Quick DASH) and Oxford Elbow Score (OES) and a record of time off work due to lateral epicondylitis in days at 1 week and at 1 month.

The study will be a cross-over trial

This project compares bupivacaine and long acting liposomal bupivacaine in the treatment of pain and disability related to lateral epicondylitis.

The investigational medicinal products will be Chirocaine, ABBVIE OY, Espoo, Finland (levobupivacaine) and Exparel®, Pacira Pharmaceuticals, Inc., Parsippany, N.J. (liposomal bupivacaine).

The design of the study will be an off-label, investigator initiated, randomized, controlled, double-Blind cross over treatment trial. Exparel (liposomal bupivacaine) will be the medicinal product in the intervention arm, whilst Chirocaine (levobupivacaine) will serve as the active control.

Patients for the study will be recruited from the patients referred to the hand surgery outpatient clinic at Turku University Hospital, Finland.

During the pilot phase of the study, four patients will be recruited, after which power analysis is done. The main study will include up to 50 patients, 25 patients in each study arm. Patient enrollment will start immediately after the all the relevant permits have been obtained (estimated September 2020).

Normal distribution of data will be tested by Shapiro-Wilks test. The mean and Standard Deviation will be reported for normally distributed data. For data not distributed normally, the median and inter quartile ranges of the data will be reported. Independent samples t-test will be used for between-group comparison (normal distribution). The Mann-Whitney test will be used for non-normal data.

The results will be published in a peer reviewed international academic journal.

Inclusion Criteria:

• written informed consent
• age 18-65
• employed
• chronic lateral epicondylitis (duration >3 months)
• pain in lateral epicondyle
• pain in resisted wrist extension in elbow extension (Cozen test)
• X-ray or Magnetic resonance imaging (MRI) of the elbow (<12 months from enrollment) with no pathological findings other than lateral epicondylitis

Exclusion Criteria:

• pregnancy, verbal confirmation from patient required
• unemployment
• allergy to levobupivacaine, bupivacaine or liposomal bupivacaine
• constant use of strong analgesics (e.g. opioids)
• other source of elbow pain (e.g. medial epicondylitis, distal biceps/triceps tendinitis)
• bilateral epicondylitis
• inability to give informed consent
• inability to understand the enrollment forms or to fill patient diary (forms are written in Finnish)
• previous injection treatment (e.g. cortisone, botulin toxin A, autologous plasma) for lateral epicondylitis during the past 3 months
• severe hepatic disease, or other underlying severe illness (cardiac failure, cancer, other systemic diseases)

A nurse at the outpatient clinic will choose an envelope with the randomization information and assign the patient into their groups. The same nurse will prepare the injection, mask the syringe with a tape and give it to the doctor who will administer the injection. The same injection technique will be used for both drugs.