Tendon tissue sampling.

Mechanical load is regarded as the most important etiologic factor in cumulative trauma disorders affecting human tendons. At present there is limited knowledge concerning adaptation and the influence of training on human tendon tissue and the time process of developing a chronic tendon disorder. Tendon tissue samples and data concerning tendon pathology and repair have been derived from biopsies removed during surgery for rupture or pain conditions and from autopsy material. The ultrasound-guided percutaneous core biopsy technique provides the possibility to obtain tendon tissue from human Achilles and patellar tendon with limited discomfort for the individual. The specimens can be used for diagnostic purposes or for research and have the potential to highlight novel knowledge in, for example, the early stages of painful human tendon disorders. The fact that the procedure is invasive is a limitation. Autopsy material has limitations regarding poor information on case history, post mortem alterations and legal regulations on the use of tissue for medical purposes. The inflammatory process quickly affects ruptured tendons. The subcutaneous tendons that sustain a rupture are commonly characterized by degenerative alterations. Many tendon ruptures are treated with surgery, facilitating easy access to biopsy material. In summary, tendon tissue sampling in humans has obvious limitations. The recently described use of the core biopsy technique in human tendon research and diagnosis gives potential for new knowledge concerning human tendon adaptation, repair and disease.