Lateral epicondylar tendinopathy (“tennis elbow”) that is refractory to the usual interventions of physical therapy/home-directed exercise, ice therapy, corticosteroid injections, and rest is a relatively common but very difficult clinical situation. Patients often become frustrated by the lack of improvement and want something to alleviate the pain and disability. However, the orthopaedic community has been reluctant to recommend surgical intervention except for the most severe cases because the outcomes of this surgery are not as predictable as we would like.
It is within this context that Creuzé et al., in the May 16, 2018 issue of The Journal, present results from a double-blind randomized trial elucidating the impact of low-dose Botulinum toxin injection on this chronic condition. Just over half of the patients treated with the Botulinum toxin injection (n = 29) had a >50% reduction in their initial pain intensity at day 90, and almost 20% felt completely cured. Those results were significantly better than those experienced by the group treated with placebo injections (n = 28).
Kudos to the industry sponsor of this study for supporting the double-blind design, because it removed a significant potential bias that might have otherwise tainted the results. The only fault I can find in the trial is a lack of reporting on the patients’ hand dominance and the magnitude of functional demand on their affected limbs. Before and after treatment, a patient who uses power tools with a dominant and affected limb during a physically demanding job may well have more severe symptoms than a person who works at a computer and whose dominant and affected limb is the “non-mouse” extremity.
It is rare indeed to find a study that blinds the administrator of an orthopaedic intervention, as injections and oral medications are not the most prominent tools in our predominantly surgical armamentarium. The inclusion criteria in the Creuzé et al. study reflected a realistic but difficult patient-enrollment scenario—a minimum of 6 months of symptoms (a mean of almost 19 months) despite previous attempts at all other well-known interventions. The fact that nearly all subjects in both groups had a previous steroid injection into the extensor carpi radialis brevis (ECRB) muscle and continued to experience symptoms confirms the difficulty of these cases and represents what many patients go through in search of an effective treatment.
Furthermore, the fact that only 50% of patients in the intervention group achieved significant pain relief reflects the refractory nature of this condition in many patients. These findings seem to indicate that surgical intervention will remain a necessary component of care for patients with lateral epicondylitis who are not cured by Botulinum toxin injection or other, more common treatment modalities—and that we should pay attention to improving surgical outcomes.
Marc Swiontkowski, MD