Athletes who play field sports that require repetitive sprinting are susceptible to suffering a hamstring strain. For the various elite football and rugby codes, a protracted hamstring injury can sideline a player for a significant amount of time, impacts team performance, and results in monetary losses. Therefore, hamstring strain prevention is a salient topic in... MORE
Think we’ve said everything about tendinopathy? Think again!
Nearly 50% of sports injuries occur at the tendon(1). That tough yet semi-elastic piece of connective tissue that connects muscles to bones still seems to be the weak link in athletic movement. As Alicia Filley reviews, we’ve come a long way from thinking of it as a purely inflammatory problem. We now know that there can be components of both inflammation and degeneration alongside healthy tendon tissue. Tracy Ward explains that the role of physiotherapy in treating tendinopathy now goes far beyond modalities. She reviews the evolution of exercise therapy and the effectiveness of heavy, slow resistance training in her article here.
So how does one explain those cases of the recalcitrant tendon? You know, the one that continues to cause an athlete pain and keep them out of competition, no matter how diligent and science-based your therapy plan has been? Physios at George Washington University thought long and hard about this question and wondered if there was more at play than the chronic pain the athlete felt at the tendon site. In a retrospective case study review, they reflected on a novel approach to treating the stubborn tendon(2).
When physiotherapy doesn’t work
Three patients presented to their clinic with chronic complaints of tendon pain for over one year. Two complained of Achilles’ tendon pain and one of patellofemoral tendon pain. The tendon pain prevented all three patients from participating in their preferred sport of running.
All three subjects underwent previous bouts of physiotherapy (PT) with a seemingly appropriate science-based protocol. The prior PT sessions provided some relief but didn’t enable them to return to full function. The practitioners suspected that the pathology at the tendon site wasn’t necessarily the primary problem. Rather, the tenacity of the pain likely stemmed from peripheral sensitization, central sensitization, or both. Therefore, they instituted a novel approach to treatment that included dealing with altered pain mechanisms.
After conducting a physical screen, functional, and provocative pain tests, the therapists also evaluated the pressure pain threshold (PPT) of each patient. The PPT test uses an algometer to apply and measure pressure to the skin. The patient is instructed to indicate when the sensation, which starts as comfortable pressure, becomes somewhat unpleasant pain. The device then measures the force applied to illicit the painful stimulus, sensing if the nervous system is overly sensitized to pain.
In the three subjects, PPT was measured in the involved tendon and compared to the uninvolved side. A reduction in stimulus necessary to elicit discomfort in the affected tendon likely indicates a peripheral sensitization. However, the practitioners also measured the PPT in the contralateral thenar eminence and compared that to established norms(3). Finding decreases in this measurement suggest that central sensitization is also at work in the pain picture, meaning the entire nervous system requires less input to trigger pain. The patients also completed other measures of pain and function, including the Visual Analog Scale (VAS), the Victorian Institute of Sport Assessment, and the Central Sensitization Inventory.
The treatment of all three patients followed a similar track with the initial evaluation and first treatment session focusing heavily on pain neuroscience education (PNE). Pain research is finding that knowledge about the science of pain improves physical treatments. Note how physical therapist Karen Litzy recommends speaking to patients about pain and how to move away from language that supports the biomedical model of pain theory.
Does pain neuroscience education pay off?
All three patients underwent five total treatment sessions over eight weeks. Treatments included joint mobilizations to address decreases in joint motion as well as pain modulation. Home exercise programs were progressed from self-stretching of the affected tendons for one minute, five times per day, to 30-45 minutes of moderate to intense cross-training aerobic exercise (also to help with pain modulation), to progressive running intervals.
By the end of the program, the PPT scores improved on the injured tendons and hand. All functional tests showed improvement, and all patients were engaged in a progressive running program. At one year follow-up via email, all patients reported a return to full function and no additional issues.
This reflective case study presents a novel approach to chronic tendon pain. Pain science reveals that pain perception is far more complicated than the physiological presentation. Sport, stress level, sleep deprivation, diet, gender, and many other variables influence pain perception. The reactions to feeling pain, including catastrophization and fear, also play a role in how quickly pain resolves. Therefore, consider integrating PNE into your therapeutic approach for those tendons that don’t seem to respond to concerted exercise-based treatment.
- J Exp Orthop. 2017 Dec; 4: 18
- 2019 April;49(4):272