Lateral Epicondyle Injection

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  I saw patient with tennis elbow 
  
  
  
  
  
  
  Lateral epicondylitis  of the elbow involves pathologic alteration in the musculotendinous origins of the extensor carpi radialis brevis and longus tendons (see image below).^{[1, 2, 3, 4]}Lateral epicondyle.
• Though commonly known as tennis elbow, lateral epicondylitis may be caused by various sports and occupational activities.
• The diagnosis of lateral epicondylitis is based upon a history of pain over the lateral epicondyle and the following findings on physical examination:
  

  • Local tenderness directly over the lateral epicondyle
  • Pain aggravated by resisted wrist extension and radial deviation
  • Decreased grip strength or pain aggravated by strong gripping
  • Normal elbow range of motion
• Strain or tear of various portions of the extensor digitorum and extensor carpi radialis brevis muscles due to repetitive use results in chronic inflammation.^[5]
• The histopathology of the affected musculature reveals edema and fibroblast proliferation in the subtendinous space, tendinopathy with hypervascularity (particularly involving the extensor carpi radialis brevis tendon), and spur formation with a sharp longitudinal ridge on the lateral epicondyle.
• Corticosteroids and other drugs often are injected in and around soft-tissue periarticular lesions to treat regional pain syndromes.
• The principles and practice of inserting a needle into a joint cavity are very similar to the principles and practice of inserting a needle into a periarticular lesion.
  
  

  Indications

  • Failure of conservative treatment
  • To shorten symptomatic period (long-term outcome is similar in patients who do or do not receive injection)^{[6, 7]}
  • To speed up recovery in high-performance athletes, although this is a controversial practice
    
    

    Contraindication

    • oint or soft-tissue aspirations and injections have few absolute contraindications.
    • The procedure should probably be avoided if the overlying skin or subcutaneous tissue is infected or if bacteremia is suspected.
    • The presence of a significant bleeding disorder or diathesis or severe thrombocytopenia may also preclude joint aspiration.
    • Aspiration of a joint with a prosthesis in it carries a particularly high risk of infection and is often best left to a surgeon using full aseptic techniques.
    • Lack of response to previous injections may be a relative contraindication.
    • If infection is suspected as the underlying cause of the musculoskeletal problem, injection of corticosteroids must be avoided for fear of exacerbating the infection. Corticosteroids are contraindicated in patients with septic arthritis.
    • Warfarin anticoagulation with international normalization ratio (INR) values in the therapeutic range is not a contraindication to joint or soft-tissue aspiration or injection.
      
      

      Anesthesia

      • Experienced clinicians often prefer to use topical ethyl chloride or no anesthetic at all.
      • This is often appropriate for joint aspiration, as the capsule is difficult to anesthetize, and a single quick needle thrust may be much less painful than the administration of local anesthesia
        
        

        Equipment

        Aspiration or injection of soft tissues may be performed as an outpatient procedure and does not require specialized equipment.^[8]

        • Needle, 25 or 27 gauge
        • Readily available syringes for injection (3-5 mL)
        • Methylprednisolone acetate 20-40 mg
        • Lidocaine 1% (0.5-1 mL) without epinephrine
          
          

          Positioning

          • Place the patient in a comfortable, supine position. This aids relaxation and guards against possible fainting.^[1]
          • Have the patient flex the affected elbow to 90° with the hand tucked under the buttock.
          • Mark the lateral epicondyle and radial head
            • Follow sterile precautions throughout the procedure.
            • Clean the skin carefully with antiseptic agents.
            • Ethyl chloride may be applied to the skin for anesthesia.
            • Insert a 5/8-inch, 25-gauge needle directly over the center of the epicondyle, perpendicular to the skin (if the patient has sufficient subcutaneous fat) or at a 45-degree angle, to a depth of 1/4 to 5/8 inch. See image below.Injection of lateral epicondyle.
            • Inject the corticosteroid and local anesthetic into the common extensor tendon origin at the lateral humeral epicondyle.
            • Infiltrate the corticosteroid deeply at the tenoperiosteal junction.
            • A painful reaction to injection or firm resistance during injection suggests that the needle is too deep and is within the body of the tendon; withdraw the needle 1/8 inch if this occurs.
            • The needle should move freely with skin traction if the tip is above the tendon; conversely, the needle sticks in place if the tip is within the body of the tendon.
            • Inject the corticosteroid at the tissue plane between the subcutaneous fat and the tendon.
            • At the end of injection, withdraw the needle swiftly and apply light pressure to the needle site.
              
              

              Pearls

              • Corticosteroid injections and infiltrations are basic treatment tools in rheumatology, orthopedics, physiatry, and general medicine.
              • Corticosteroid injections and infiltrations carry minimal risk to the patient when properly indicated and performed.
              • Technical difficulties vary; some of these procedures require specialized knowledge for optimal results.
              • Precaution: Avoid injecting too superficially.
              • Lack of improvement with lidocaine infiltration suggests an alternative diagnosis, such as compressive neuropathy of the deep branch of the radial nerve or cervical radiculopathy.
              • Reinjection may be necessary in 4-6 weeks if symptoms have not been reduced by at least 50%.
              • Surgical consultation can be considered if 2 injections combined with wrist immobilization fail to resolve the condition.
              • For chronic cases, no more than 4 injections should be performed in the same arm.
                
                

                Complications

                Surprisingly few complications arise as results of these procedures.^{[1, 2]}

                • The most significant issue is the risk of infection. Care must always be taken to use sterile techniques. Corticosteroids are contraindicated in patients with septic arthritis.
                • The estimated risk of septic arthritis following a corticosteroid injection is on the order of 1 per 15,000 procedures.^[9]
                • Patients with severe immunodeficiency or implants may be at greater risk of complications.
                • Other complications can arise from misplaced injections.
                  

                  • The best-described complication is tendon rupture following corticosteroid injections for tendonitis. The risk of this complication can be minimized by avoiding injection into the tendon itself. No therapeutic agent should be injected against any unexpected resistance.
                  • Occasionally, nerve damage can also result from a misplaced injection (eg, median nerve atrophy following attempted injections for carpal tunnel syndrome).
                • Transient increase in pain is seen in 20-40% of patients.
                • Repeated corticosteroid infiltrations may result in chronic pain.
                • Superficial corticosteroid infiltrations often cause a hypopigmented patch, which may be quite disfiguring in people with dark skin. The condition resolves in a few months to 2 years.
                • Skin atrophy is a frequent complication of superficial infiltrations.
                • Rarely, corticosteroid injections can cause transient pituitary inhibition that lasts up to several days. Serial infiltrations may cause adrenal suppression and result in acute adrenal crisis.
                • Patients who have been injected serially are at an enhanced risk of localized osteoporosis.