Radial Tunnel Syndrome in Resistant Lateral Epicondylitis
Condition: Radial Tunnel Syndrome; Lateral Epicondylitis; Radial Nerve Compression; Epicondylitis of the Elbow
MeSH terms: Tennis Elbow; Radial Neuropathy; Syndrome
Study type: Interventional

Summary: 
      Lateral elbow pain can be difficult to diagnose because of the different pathologies or
      combinations of pathologies that can cause this clinic. Although lateral epicondylitis is the
      most common cause of lateral elbow pain, symptoms of radial tunnel syndrome may masquerade as
      lateral epicondylitis or they can be seen together with rate of 21-41%. The aim of the study
      is; to evaluate the presence of radial tunnel syndrome in the patients who have resistant
      lateral epicondylitis.
    

Detailed description: 
      Lateral epicondylitis (LE), also known as "tennis elbow," is an overuse syndrome of the
      common extensor tendon (CET), predominantly affecting the extensor carpi radialis brevis.
      History and physical examination including manual provocation tests are key elements for the
      diagnosis.

      Ultrasound imaging of the CET is an important complementary method to the clinical diagnosis
      of LE. It provides information about the severity of the disease with evidence of tendon
      thickening, focal/diffuse areas of decreased echogenicity in the tendon, epicondylar cortical
      irregularity or spur formation, and increased vascularity in case of local inflammation
      depicted by power- Doppler imaging.

      Radial tunnel syndrome (RTS) is a dynamic/intermittent compression neuropathy of the radial
      nerve, where different structures can potentially compress the nerve. Local inflammatory
      and/or vascular changes (scarring, fibrosis), which are seen in LE may lead to compression of
      the radial nerve or its branches (especially the deep branch) at the radial tunnel. While RTS
      can often be the cause of refractory LE, some patients with LE actually have RTS
      concomitantly. The diagnosis of RTS is difficult/controversial due to inconclusive findings
      on electrophysiological tests and its close relationship with LE. Ultrasound is a superior
      imaging modality that can be used as an adjunct to electromyography for the evaluation of
      peripheral nerve problems. It can be used to diagnose compression neuropathies and to
      identify the entrapment site of the nerve. For the exact diagnosis of RTS complete relief
      should be achieved with a nerve block at the radial tunnel. Patients who have RTS coexisting
      with LE (18-43%) usually experience incomplete relief.

      The purpose of the study is; to evaluate the RTS and LE with physical examination, special
      clinical tests, electrophysiological and ultrasonographic examinations and, to confirm the
      presence of RTS accompanying LE with the evaluation of clinical findings after the posterior
      interosseous nerve and lateral epicondyle diagnostic injections.
    

Intervention name(s): diagnostic posterior interosseous nerve lidocaine injection
Intervention type(s): Diagnostic Test
Intervention description(s): ultrasound guided posterior interosseous nerve and lateral epicondyle 1 ml 2% lidocaine injection
Other intervention name(s): diagnostic lateral epicondyle lidocaine injection
Intervention MeSH terms: Lidocaine
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Diagnostic
Keywords: radial nerve; radial tunnel syndrome; lateral epicondylitis; ultrasonography; electrophysiology