Rolf Christer G, Fu Sai-Chuen, Hopkins Chelsea, Luan Ju, Ip Margaret, Yung Shu-Hang, Friman Göran, Qin Ling, Chan Kai-Ming
Division of Orthopaedics and Biotechnology, Department of Clinical Science, Intervention and Technology, Karolinska Institutet, Stockholm, Sweden.
Lui Che Woo Institute of Innovative Medicine, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
Am J Sports Med. 2017 Jul;45(9):2061-2067. doi: 10.1177/0363546517696315. Epub 2017 Mar 29.
The structural pathology of Achilles tendon (AT) ruptures resembles tendinopathy, but the causes remain unknown. Recently, a number of diseases were found to be attributed to bacterial infections, resulting in low-grade inflammation and progressive matrix disturbance. The authors speculate that spontaneous AT ruptures may also be influenced by the presence of bacteria.
Bacteria are present in ruptured ATs but not in healthy tendons.
Cross-sectional study; Level of evidence, 3.
Patients with spontaneous AT ruptures and patients undergoing anterior cruciate ligament (ACL) reconstruction were recruited for this study. During AT surgical repair, excised tendinopathic tissue was collected, and healthy tendon samples were obtained as controls from hamstring tendon grafts used in ACL reconstruction. Half of every sample was reserved for DNA extraction and the other half for histology. Polymerase chain reaction (PCR) was conducted using 16S rRNA gene universal primers, and the PCR products were sequenced for the identification of bacterial species. A histological examination was performed to compare tendinopathic changes in the case and control samples.
Five of 20 AT rupture samples were positive for the presence of bacterial DNA, while none of the 23 hamstring tendon samples were positive. Sterile operating and experimental conditions and tests on samples, controlling for harvesting and processing procedures, ruled out the chance of postoperative bacterial contamination. The species identified predominantly belonged to the Staphylococcus genus. AT rupture samples exhibited histopathological features characteristic of tendinopathy, and most healthy hamstring tendon samples displayed normal tendon features. There were no apparent differences in histopathology between the bacterial DNA-positive and bacterial DNA-negative AT rupture samples.
The authors have demonstrated the presence of bacterial DNA in ruptured AT samples. It may suggest the potential involvement of bacteria in spontaneous AT ruptures.
跟腱（AT）断裂的结构病理学与肌腱病相似，但其病因仍不明。最近，发现一些疾病归因于细菌感染，导致低度炎症和渐进性基质紊乱。作者推测自发性跟腱断裂也可能受细菌存在的影响。
细菌存在于断裂的跟腱中，但不存在于健康肌腱中。
横断面研究；证据等级，3级。
本研究招募了自发性跟腱断裂患者和接受前交叉韧带（ACL）重建的患者。在跟腱手术修复过程中，收集切除的肌腱病组织，并从ACL重建中使用的绳肌腱移植物中获取健康肌腱样本作为对照。每个样本的一半留作DNA提取，另一半用于组织学检查。使用16S rRNA基因通用引物进行聚合酶链反应（PCR），并对PCR产物进行测序以鉴定细菌种类。进行组织学检查以比较病例和对照样本中的肌腱病变化。
20个跟腱断裂样本中有5个细菌DNA呈阳性，而23个绳肌腱样本均无阳性。无菌手术和实验条件以及对样本的检测，控制了采集和处理程序，排除了术后细菌污染的可能性。鉴定出的菌种主要属于葡萄球菌属。跟腱断裂样本表现出肌腱病的组织病理学特征，大多数健康的绳肌腱样本显示正常的肌腱特征。细菌DNA阳性和细菌DNA阴性的跟腱断裂样本在组织病理学上没有明显差异。
作者已证明在断裂的跟腱样本中存在细菌DNA。这可能表明细菌可能参与自发性跟腱断裂。
