The effects of extracorporeal shock waves on carrageenan-induced Achilles tendinitis in rats: a biomechanical and histological analysis

Abstract

Objective: The aim of this study was to investigate the influence of low-dose extracorporeal shock waves (ESW) on the healing potential of Achilles tendinitis in the rat.
Methods: The 36 adult Sprague-Dawley rats used in this study were randomly divided into four groups. Group A (n=10) were injected with carrageenan, Group B (n=10) were injected with carrageenan and received ESW, Group C (n=10) received ESW only, and Group D (n=6) was a sham group. Rats were injected with 10 microliters of 3% carrageenan or a saline solution eight times during a one-week period with a subcutaneous needle. One week following the final injection, ESW was applied at a rate of 500 impulses in 5 minutes at 2 bars (comparative to 0.09 mJ/mm2) to rats in Groups B and C. Rats were sacrificed three weeks later. Tensile strength, inflammation, and vascularity and collagen density were measured.
Results: Failure of the tendon ultimate loads was significantly lower in the study groups than in the control group (p<0.05). Collagen fiber density was higher in the control group than in the other groups (p=0.59). No other histological differences were found.
Conclusion: Low-dose ESW has a negative effect on tendon tensile strength in this animal model.

Keywords

• Achilles tendinitis
• biomechanical analysis
• extracorporeal shock wave
• histological analysis
• rat

Sıçanlarda karragenan ile uyarılmış Aşil tendinitinde ekstrakorporeal şok dalgalarının etkinliği: Biyomekanik ve histolojik bir değerlendirme

Öz

Amaç: Bu çalışmanın amacı sıçanlarda Aşil tendinitinin iyileşmesinde düşük doz ekstrakorporeal şok dalgaların etkinliğinin incelenmesi idi. Çalışma planı: Çalışmada kullanılan 36 adet Sprague-Dawley sıçanı dört gruba ayrıldı. Grup A, karragenan enjekte edilen 10 sıçan, Grup B karragenan ve ekstrakorporeal şok dalga uygulanan 10 sıçan, Grup C ekstrakorporeal şok dalga uygulanan 10 sıçan ve Grup D kontrol grubu olarak 6 sıçandan oluşmaktaydı. Sıçanlara 10 mikrolitre %3’lük karragenan veya salin çözeltisi bir hafta içinde 8 defa subkutan iğne ile uygulandı. Son enjeksiyondan bir hafta sonra Grup B ve Grup C’deki sıçanlara 500 atım şok dalga 5 dakika süre ile 2 bar (yaklaşık 0.09 mJ/mm2) düzeyinde uygulandı. Sıçanlar üç hafta sonra sakrifiye edildi. Tendon gerim direnci, enflamasyon ve damarlanma ve kolajen yoğunlukları ölçüldü. Bulgular: Çalışma gruplarındaki tendon gerim direncinin kontrol grubuna göre anlamlı düzeyde daha düşük olduğu belirlendi (p<0.05). Kolajen liflerin yoğunluğu kontrol grubunda diğer gruplardan daha yüksekti (p=0.59). Histolojik başka bir farklılık belirlenmedi. Çıkarımlar: Bu hayvan modelinde düşük doz ekstrakorporeal şok dalgasının tendon gerim direncine olumsuz etkisi olduğu görülmüştür.

Anahtar Kelimeler

• Aşil tendiniti; biyomekanik inceleme; ekstrakorporeal şok dalga; histolojik inceleme; sıçan

Kaynakça

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