Immune-competent cells were present in the majority of biopsy specimens from nonruptured chronic tendinopathic Achilles tendons, according to study results.
Fifty patients with nonruptured chronic Achilles tendinopathy and 15 healthy participants underwent an ultrasound examination immediately before an ultrasound-guided Achilles tendon biopsy specimen was obtained. Researchers used a stereological technique to quantify the presence of macrophages, hemosiderophages, T lymphocytes, B lymphocytes, natural killer cells, mast cells, Schwann cells and endothelial cells and evaluated tissue samples immunohistochemically. More than 4 years after the biopsy procedure, the researchers conducted a follow-up examination to evaluate the long-term presence of Achilles tendon symptoms.
The majority of biopsy specimens from nonruptured chronic tendinopathic Achilles tendons had macrophages, T lymphocytes, mast cells and natural killer cells, according to the researchers. Results showed tendinopathic tendons had significantly more CD68-KP1+ macrophages and CD34+ endothelial cells compared with healthy tendons.
Compared with the symptomatic group, the researchers frequently observed more iron+ hemosiderophages in biopsy specimens in the asymptomatic group at follow-up.
Disclosure: This work was funded by grants from the Department of Clinical Medicine, Aarhus University Hospital and the Danish Research Fund of the Hospital of Region Mid.