Lateral epicondylitis is a painful condition related to the myotendinous origin of the extensor muscles at the lateral epicondyle of the humerus. Primary treatment typically involves the use of rest, non-steroidal anti-inflammatory drugs (NSAIDs), and physiotherapy. However, in refractory cases where conventional therapy is ineffective, ultrasound-guided injection therapies have become a growing form of treatment. These include needle tenotomy, autologous whole blood injection (AWB), platelet-rich plasma (PRP) injection and steroid injection. The consensus regarding the efficacy of individual approaches of ultrasound-guided treatment is unclear in the literature, and is explored further in this review.
When evaluating these injection therapies individually, there are multiple case series describing the efficacy of each intervention in refractory lateral epicondylitis. A systematic review of needle tenotomy demonstrates an improvement in pain symptoms for patients with this condition, but all studies were poorly designed with no placebo or control group. Additionally, for PRP therapy, a systematic review performed in 2013 demonstrated a statistically significant improvement in pain and functionality for refractory lateral epicondylitis. However, these studies were similarly associated with a high risk of bias. Autologous whole blood injection has been evaluated through well-designed studies to show statistically significant reductions in pain with this intervention. But very few studies in total have been completed using AWB for lateral epicondylitis, and therefore no clear conclusions can be drawn at this time. Finally, corticosteroid use overall is unsupported in the evidence both in the short and long term, especially given that this condition is not an inflammatory pathology.