Clinical and Ultrasonographic Results of Intratissue Percutaneous Electrolysis in Lateral Epicondylitis
Condition: Lateral Epicondylitis
MeSH terms: Tennis Elbow
Study type: Observational

Summary: 
      Lateral epicondylitis (LE) is the most common cause of lateral elbow pain. Intratissue
      percutaneous electrolysis (EPI technique) is a novel minimally invasive approach which
      consists in the application of a galvanic current through a puncture needle which produces a
      local inflammatory process in the soft tissue and the reparation of the affected tissue.

      The purpose of this study is to evaluate the clinical and ultrasonographic effectiveness of a
      multimodal program using the intratissue percutaneous electrolysis technique and exercises in
      the short term for patients with chronic lateral epicondylitis, and to determine whether the
      clinical outcomes achieved decline over time.

      This study is an observational one-way repeated measures design. 36 patients in a clinical
      setting presenting with lateral epicondylitis (mean age = 38, mean time since injury = 12.6
      months) received one session of EPI per week over 4-6 weeks, associated with a home program
      of eccentric exercise and stretching. The main outcome measures were severity of pain (VAS,
      digital algometer, Cozen and Thompson tests), disability (DASH questionnaire), structural
      tendon changes (ultrasound), hypervascularity (power doppler) and patient's perceptions of
      overall outcome (4-point scale). Measurements at 6, 26 and 52 weeks follow-up included
      recurrence rates (increase of severity of pain or disability compared to discharge), the
      perception of overall outcome and success rates. Paired Student t-tests and Chi squared tests
      were applied to data. Enrollment into this study ended in September 2012.

      All outcome measures registered significant improvements between pre-intervention and
      discharge. Most patients (30, i.e. 83.3%) rated overall outcome as 'successful' at 6 weeks.
      The ultrasonographic finding revealed that the hypoechoic regions and hypervascularity of the
      extensor carpi radialis brevis change significantly. At 26 and 52 weeks, all participants
      (32) perceived a 'successful' outcome. Recurrence rates were null after discharge, and at the
      6, 26 and 52 week follow-ups.
    

Detailed description: 
      Patients received one session of EPI technique per week over 4 weeks (or over 6 weeks when
      pain persisted) associated with a home program consisting of eccentric exercise (EccEx) and
      stretching, initiated 24 hours after each session. The EccEx and stretching program was
      taught by a physiotherapist in the first session and monitored in subsequent sessions. At
      discharge, patients were instructed to perform only EccEx once daily for the first 6 weeks of
      the follow-up period.

      The EPI technique was performed under ultrasound-guidance on the clinically relevant area (or
      areas of maximum tenderness to palpation and with ultrasonographic degenerative tendon
      changes) using an intensity of 4-6 milliampere (mA) during 3 seconds, approximately 3 times.
      The investigators used the EPI machine (Cesmar Electromedicina S.L., Barcelona, Spain) and a
      GE Logiq E Portable Ultrasound Machine with GE Linear probe 12L-RS (5-13 mhz) (GE Healthcare,
      Wisconsin, EEUU). During the EPI technique, the patient was placed in a supine position, with
      the affected elbow placed in a position of 90° flexion and maximum pronation. The elbow was
      sterilized and the sonographic transducer, enclosed in a sterile cover over sterile applied
      gel, was placed at the lateral epicondyle (first approach) and over the humeroradial joint
      between the head of the radius and the capitulum of the humerus (second approach), where it
      remained throughout the procedure. A common target area was the deep surface of the common
      extensor tendon (origin of the ECRB [extensor carpi radialis brevis] and the EDC [extensor
      digitorum communis]) (first approach) and the deep surface of the ECRB, over the capsule and
      the lateral ulnar collateral ligament (second approach). A 0.3 x 25mm. (1 inch) needle was
      inserted at a 30° to 45° angle to the skin in the direction of the lateral epicondyle (first
      approach) and at a 80° angle to the skin, with the needle tip directed towards the
      humeroradial joint (second approach). In the first approach the needle was advanced parallel
      to the longitudinal plane of the tendon (in-plane approach); whereas in the second approach
      the needle was advanced along the short plane of the humeroradial joint (out-of-plane
      approach). Real-time ultrasonographic imaging provided guidance for both procedures. Once the
      needle reached the target tissue, readjustments of the needle position were made in order to
      ensure a correct stimulation. The generation of the galvanic current creates a white image
      (hyperechoic) as a result of the liberation of hydrogen gas due to the electrolysis. Oral
      paracetamol was used when necessary for the purpose of pain relief only.

      The eccentric exercise program consisted of three series of up to 10 repetitions of eccentric
      work, repeated twice daily (morning and afternoon), under maximum load (initially with one
      kilogram) in an optimal and functional pain-free range. From maximum wrist extension and
      radial deviation, rapid wrist flexion movement were performed, followed by a 2-second hold of
      the final position. In between series patients were given a rest period of 2-3 minutes. This
      formula was used for the duration of the physiotherapy program. The concentric contraction
      phase for returning to the starting position was nullified with the help of the other hand.

      The stretching program consisted of a stretching exercise for the epicondylar muscles
      consisting in three series of 7 repetitions twice a day (morning and afternoon), performed in
      a sitting position with a flexed wrist and fingers, ulnar deviation and elbow extension
      reaching the stretch limit without bounces, and held for 45 seconds, with a 30-second rest
      between repetitions.
    

Intervention name(s): Intratissue percutaneous electrolysis, associated with eccentric exercise and stretching
Intervention type(s): Other
Intervention description(s): The EPI technique was performed under ultrasound-guidance on the clinically relevant area (or areas of maximum tenderness to palpation and with ultrasonographic degenerative tendon changes) using an intensity of 4-6 mA during 3 seconds, approximately 3 times. We used the EPI machine (Cesmar Electromedicina S.L., Barcelona, Spain) and a GE Logiq E Portable Ultrasound Machine with GE Linear probe 12L-RS (5-13 mhz) (GE Healthcare, Wisconsin, EEUU).
The eccentric exercise program consisted of three series of up to 10 repetitions of eccentric work, repeated twice daily (morning and afternoon), under maximum load (initially with one kilogram) in an optimal and functional pain-free range.
The stretching program consisted of a stretching exercise for the epicondylar muscles consisting in three series of 7 repetitions twice a day (morning and afternoon.
Observational model: Case-Only
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        36 participants with lateral epicondylitis
      
Keywords: Tennis elbow; Lateral epicondylitis; Intratissue percutaneous electrolysis; Eccentric exercise; Ultrasonography