Background
No single injection therapy has been proven to be superior in the treatment of lateral epicondylitis. In most studies, the injection technique is not standardized, which makes it challenging to compare outcomes.
Questions/purposes
(1) Does injection with autologous blood, dextrose, or needle perforation only at the extensor carpi radialis brevis tendon origin produce better VAS pain scores during provocation testing at 5 months of follow-up? (2) Which percutaneous technique resulted in better secondary outcome measures: VAS during rest and activity, VAS during maximum grip, Oxford elbow score (OES), QuickDASH, Patient-related Tennis Elbow Evaluation (PRTEE), or EuroQol-5D (EQ-5D)?
Methods
In this multicenter, randomized controlled trial performed from November 2015 to January 2020, 166 patients with lateral epicondylitis were included and assigned to one of the three treatment groups: autologous blood, dextrose, or perforation only. Complete follow-up data were available for the primary outcome measures at the 5-month follow-up interval for 77% (127 of 166) of patients. Injections of the extensor carpi radialis brevis tendon were conducted in an accurate and standardized way. The three groups did not differ in terms of key variables such as age, gender, duration of symptoms, smoking habits, pain medication, and physiotherapy use. Data were collected at baseline and 8 weeks, 5 months, and 1 year after treatment and compared among the groups. The primary endpoint was the VAS pain score with provocation at 5 months. Our secondary study outcomes were VAS pain scores during rest, after activity, and after maximum grip strength; functional recovery; and quality of life. Therefore, we report the VAS pain score (0 to 100, with higher scores representing more-severe pain, minimum clinically important difference [MCID] 10), OES (0 to 48, with higher scores representing more satisfactory joint function, MCID 10), QuickDASH (0 to 100, with higher scores representing more severe disability, MCID 5.3), PRTEE (0 to 100, with higher scores representing more pain or more disability, MCID 20), EQ-5D/QALY (EQ-5D sumscore 0 to 1, with the maximum score of 1 representing the best health state, MCID 0.04), and EQ-5D VAS (0 to 100, with higher scores representing the best health status, MCID 8). For analysis, one-way analysis of variance and a linear mixed-model analysis were used. The analyses were performed according to the intention-to-treat principle. Four patients from the perforation group opted to crossover to autologous blood after 5 months.
Results
No injection therapy proved to be superior to any other in terms of VAS pain scores during the provocation test at 5 months of follow-up (VAS for perforation: 25 ± 31; autologous blood: 26 ± 27; dextrose: 29 ± 32; p = 0.35). For the secondary outcomes, only a clinically important difference was found for the QuickDASH score. Both the perforation-only group (-8 [98% CI -4 to -12]) and autologous blood (-7 points [98% CI -3 to -11]) had improved QuickDASH scores over time compared with the dextrose group (MCID 5.3; p < 0.01). For the other outcomes, no clinically important differences were found.
Conclusion
There is no benefit to injectable autologous blood and dextrose over perforation alone to treat lateral epicondylitis, and they are therefore not indicated for this condition.
Level of Evidence
Level I, therapeutic study.