[Arthroscopic Finding of Knee Joint in Relation to Age and Its Comparison with Pre-Operative Clinical Finding - a Retrospective Study].

PURPOSE OF THE STUDY In the retrospective study of two South Bohemian centres we present the comparison of pre-operative anamnestic clinical signs in relation to the arthroscopic intraoperative finding. The obtained data is used also to evaluate the arthroscopic finding in relation to age and sex. MATERIAL AND METHODS The arthroscopic findings of patients who underwent surgery in 2013-2014 period (1.1.2013-31.12.2014) at the Department of Trauma Surgery of České Budějovice Hospital, a.s. and in 2014 (1.1.-31.12.2014) at the Department of Orthopaedics and Traumatology of Písek Hospital, a.s. were evaluated. In total, 1 021 patients underwent surgery, with the mean age of 44 years. The patients were not selected. The group includes all the patients who underwent surgery, including those in whom repeat arthroscopy was performed, in the respective period of time, regardless of the mechanism of difficulties. A preoperative MRI scan was carried out in 470 patients. The referring physician was present during the examination. In all the patients undergoing surgery, the main clinical preoperative sign was examined based on the documentation, namely in the following order - hemarthros, locked knee, hydrops or merely a pain. In the arthroscopic finding, the medial meniscal lesion - anterior and posterior horn, and complete tear was assessed. The same was done for lateral meniscus. In anterior cruciate ligament - ACL - partial or complete tear was assessed. We identified the frequency of findings in relation to age and evaluated the correlations between the clinical signs and the arthroscopic finding. We calculated the sensitivity and specificity of hemarthros as a sign of ACL tear. The analysis was conducted based on the medical history in medical record documentation and the surgical protocol. The cartilage was not assessed. RESULTS Analysis of clinical and anamnestic signs in relation to arthroscopic findings 1. Negative arthroscopic findings (potential cartilage damage with no damage to other soft structures and normal arthroscopic findings) are in 83% accompanied by a mere knee pain. 2. High percentage of isolated locked joint (15%) in negative findings 3. Complete ACL tears are most frequently reported in the under-35 age category - 43% of 191 men who underwent surgery and 33% of 102 women. 4. Isolated injuries to ACL without the meniscus tear are frequent in younger patients - 30% - 40% of the total number of patients with injured ACL. 5. In patients older than 56 years of age the ACL damage is accompanied by concurrent meniscus tear (96% in men, 100% in women). 6. Sensitivity of hemarthros (68%) for complete ACL tear. Specificity of the presence of hemarthros in complete ACL lesions (91%) indicates that there are also complete ACL tears with no hemarthros whatsoever in the medical history. For partial tears the values of sensitivity and specificity are 27% and 67%, respectively. In partial tear, the presence of hemarthros is not a diagnostic lead. 7. In 15% of negative findings a "locked knee" was present. It was not a genuinely locked knee, but rather an antalgic position. Not every locked knee must necessarily mean a meniscus lesion or ACL tear. 8. Isolated meniscus tear is in 75% accompanied only by pain. 9. In our group of patients, isolated osteoarthrosis or malacic cartilage without any damage to ligaments or menisci was rare - only in 22 cases (2% of the entire group). DISCUSSION There are lots of studies which focus on comparing the clinical findings with perioperative pathology of knee joint and the importance of pre-operative clinical examination. Our extensive retrospective study proved that in 56-plus age category virtually each ACL injury is accompanied by a meniscal lesion, which can be explained by a possible ACL damage at a young age and subsequent instability resulting in meniscus tear or frequent presence of degenerative meniscal changes at an older age. A small number of isolated degenerative cartilage damage was established (2%). We fully agree with the authors who prove that the degenerative cartilage changes are ever since the very beginning accompanied by changes of the other soft structure of the knee. We revealed a high percentage of locked knee joint in negative arthroscopic findings. According to the clinical pre-operative examination, the locked knee does not automatically mean the meniscal lesion or ACL tear. In agreement with the others we prove a close association between hemarthros and ACL injury. CONCLUSIONS 1. A clinical examination, a detailed medical history is necessary 2. With hemarthros in medical history, there is a likelihood of complete ACL tear. Conversely, even a seemingly trivial knee sprain without hemarthros or locked knee can mean the ACL tear. 3. Where a mere pain is present, it mostly indicates an isolated meniscal damage or a negative finding. 4. Degenerative cartilage changes are accompanied by degeneration of menisci and ligaments. 5. Our group of patients did not include any case of hemarthros in the medical history with a negative arthroscopic finding. Hemarthros always indicated a more serious damage to knee soft structures. Key words: knee joint injuries, knee arthroscopy, sensitivity, specificity, hemarthros.