Is Chronic Tendon Pain Caused by Neuropathy? Exciting Breakthroughs may Direct Potential Treatment
PainSci notes on Palee 2024:
Chronic tendinitis could be a caused of wayward nerves making themselves at home where they don’t belong. That’s the takeaway from this review of a growing body of research suggesting that chronic tendon pain (tendinopathy) isn’t just a mechanical wear-and-tear issue but may have a strong neuropathic (nerve-related) component.
Recent evidence suggests that rogue nerve fibers sprouting inwards, into the tendon from its more sensitive sheath, could be the major mechanism of the chronicity for tendinitis.
A good mechanistic understand of a disease is usually necessary to figure out how to treat it. This etiology suggests that precise excision of the unruly nerve fibers could offer much-needed relief. The paper highlights emerging techniques like percutaneous ultrasound-guided tenotomy (PUT) and high-frequency ultrasound treatments, which aim to disrupt this pathological nerve invasion. The idea is to stop the pain at its source by severing the inappropriate nerve supply: simplistic in principle, but perhaps correct. In fact, this could even explain for why several less precise treatment strategies are notorious for being partially or erratically successful.
While the research is definitely intriguing, and the authors seem excited about it, they also acknowledge that it’s still early days. The link between nerve growth and pain isn’t fully understood — why does it happen, and why does it hurt, exactly? And there’s a lot more work to be done to confirm whether these new treatments actually work.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
BACKGROUND: Tendinopathy significantly impacts the quality of life and imposes a high economic burden, accounting for a large proportion of sports and musculoskeletal injuries. Traditionally considered a collagen-related inflammatory disorder, emerging evidence suggests a critical role of neuropathic processes in chronic tendon pain.
OBJECTIVE: This review aims to evaluate the neuropathic mechanisms in tendinopathy and discuss innovative treatments targeting these pathways.
METHODS: We analyze recent studies highlighting the tendon innervation, pathological nerve sprouting neuronal ingrowth in tendinopathy, and the associated increase in pain and neuronal mediators.
RESULTS: Chronic tendinopathy exhibits nociceptive sprouting from paratenon into the fibrous tendon proper. Innovative treatments such as Percutaneous Ultrasound-Guided Tenotomy (PUT) or high-frequency ultrasound interventions show promise in targeting these neuropathic components by paratenon separation. These approaches focus on disrupting the pathological innervation cycle.
CONCLUSION: Chronic tendon pain may be predominantly neuropathic, driven by pathologic neuronal ingrowth from paratenon into the tendon proper. Interventions that accurately target and disrupt these nerve pathways could revolutionize the treatment of tendinopathy. Further research is required to validate these findings and refine treatment modalities to ensure safety and efficacy.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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