No significant histological or ultrastructural tendinosis changes in the hamstring tendon in patients with mild to moderate osteoarthritis of the knee?

Purpose - To investigate the periarticular degenerative changes of the knee joint in association with osteoarthritis (OA). More tendinosis was expected to be found in the semitendinosus tendon in patients with knee OA than in patients without knee OA. Methods - Samples from 41 patients were included between January 2016 and October 2017. Twenty-one patients median age 53 (33–63) years with mild to moderate OA underwent high tibial osteotomy (HTO) and 20 patients median age 38 (31–57) years without OA underwent anterior cruciate ligament reconstruction (ACLR). Biopsies from the semitendinosus tendon were obtained at the time of surgery and examined histologically, morphologically and ultrastructurally using light and electron microscope. Results - The histological evaluation of the semitendinosus tendon revealed the presence of more hemosiderin in the ACLR group. No significant morphological or ultrastructural differences were shown between patients in the HTO and ACLR group. Conclusion - Patients with mild and moderate medial compartment knee OA displayed no more degenerative changes in their semitendinosus tendon than patients without OA, as seen in both the light and the electron microscope

More histologic and ultrastructural degenerative signs in the subscapularis tendon and the joint capsule in male patients with shoulder impingement

Purpose: The purpose of the present study was to analyze biopsy samples from the subscapularis tendon and from the joint capsule from male patients with shoulder impingement syndrome (SAIS) and compare them with samples from male patients with post-traumatic recurrent shoulder instability. The hypothesis of the study was that patients with SAIS would have more histologic and ultrastructural degenerative changes in their subscapularis tendon and joint capsule than patients with post-traumatic recurrent shoulder instability. Methods: Male patients scheduled for surgery, with either subacromial decompression or Bankart reconstruction, were included. Four biopsies from each patient were obtained from the capsule and four from the subscapularis tendon during arthroscopic surgery. The histologic characteristics and the presence of glycosaminoglycans were assessed using the light microscope, and the ultrastructure was assessed using a transmission electron microscope. Results: Eight patients, median age 53 (45–74) years (p  Conclusion: Male patients with subacromial impingement have more histologic and ultrastructural degenerative changes in their shoulder compared with patients with post-traumatic recurrent shoulder instability. Clinical relevance: It appears that in patients with subacromial impingement, the whole shoulder joint is affected and not only the subacromial space. It is the opinion of the authors that intra-articular therapeutic injections could be tried more often in these patients. Level of evidence: III