Dose dependent inhibitory effects on tendon healingPosted by Jan R. on 6/21/04 at 09:29 (153590)
Chen YJ, Wang CJ, Yang KD, Kuo YR, Huang HC, Huang YT, Sun YC, Wang FS.
Extracorporeal shock waves promote healing of collagenase-induced Achilles tendinitis and increase TGF-beta1 and IGF-I expression.
J Orthop Res. 2004 Jul;22(4):854-61:
Extracorporeal shock waves (ESW) have recently been used in resolving tendinitis. However, mechanisms by which ESW promote tendon repair is not fully understood. In this study, we reported that an optimal ESW treatment promoted healing of Achilles tendintis by inducing TGF-beta1 and IGF-I. Rats with the collagenease-induced Achilles tendinitis were given a single ESW treatment (0.16 mJ/mm(2) energy flux density) with 0, 200, 500 and 1000 impulses. Achilles tendons were subjected to biomechanical (load to failure and stiffness), biochemical properties (DNA, glycosaminoglycan and hydroxyproline content) and histological assessment.
ESW with 200 impulses restored biomechanical and biochemical characteristics of healing tendons 12 weeks after treatment.
However, ESW treatments with 500 and 1000 impulses elicited inhibitory effects on tendinitis repair.
Histological observation demonstrated that ESW treatment resolved edema, swelling, and inflammatory cell infiltration in injured tendons. Lesion site underwent intensive tenocyte proliferation, neovascularization and progressive tendon tissue regeneration. Tenocytes at the hypertrophied cellular tissue and newly developed tendon tissue expressed strong proliferating cell nuclear antigen (PCNA) after ESW treatment, suggesting that physical ESW could increase the mitogenic responses of tendons. Moreover, the proliferation of tenocytes adjunct to hypertrophied cell aggregate and newly formed tendon tissue coincided with intensive TGF-beta1 and IGF-I expression. Increasing TGF-beta1 expression was noted in the early stage of tendon repair, and elevated IGF-I expression was persisted throughout the healing period.
Together, low-energy shock wave effectively promoted tendon healing. TGF-beta1 and IGF-I played important roles in mediating ESW-stimulated cell proliferation and tissue regeneration of tendon.
My personal view: The more experimental data become available to the public the more one should re-think over single application of high-energy shock waves. A repeated fractionated application of a small dose may have equal results but less side effects than a single application of a high dose - the same is true for radiation therapy in oncologic patients.
Re: Dose dependent inhibitory effects on tendon healingPauline on 6/21/04 at 12:24 (153609)
Thank you for your post and personal opinion. If more research continues to show repeated low energy treatments perform as well as a single higher dose along with the advantage of less side effects that's very benificial to a patient. I can also see it having the added advantage of less cost for them. A win, win, win situation.
Keep the new data coming. New options and doors seem to open daily on ESWT as researchers like yourself continue to seek answers for us.
Re: Dose dependent inhibitory effects on tendon healingDr. Z on 6/21/04 at 13:00 (153614)
Dr Rompe/ Pauline
This is an excellent article. What would really be nice is if we need what total dose healed the best with the least amount of side effects.
I find that most of the side effects that I see/hear about are local anesthetic technique and improper diagnosis.
Re: Dose dependent inhibitory effects on tendon healingAmyM on 6/21/04 at 14:08 (153621)
I'm interested in the scientific detail of these experiments but I don't have access to the journal. How was the induction of TGF IGF and PCNA measured, at the protein level or mRNA? Have any similar studies been carried out on cell culture models?
Re: Dose dependent inhibitory effects on tendon healingJan R. on 6/22/04 at 00:47 (153672)
Send your e-mail to (email removed), and I will attach the article for you.
Re: Dose dependent inhibitory effects on tendon healingEd Davis, DPM on 6/24/04 at 13:42 (153839)
I agree with you both from the standpoint of efficacy, safety (no anesthesia required) and cost. This appears to be the trend in Europe. I note that HMT, manufacturer of the Ossatron is now manufacturing the low energy Reflectron (but not in the US).
Histologic observation, in my opinion, remains the most effective means of validating this technology due to the proximity of the effect and the lack of influence of other variables.