# Comparison of Diagnostic Accuracy of Physical Examination and MRI in the Most Common Knee Injuries
## 4 Discussion  
Knee joint disfunction is one of the most common problems in daily orthopaedic practice. It may be caused by previous injuries, congenital disorders or other conditions acquired during living, which, untreated, may lead to irreversible osteoarthritis changes of the knee joint. As in the published literature [22; 23; 24], the most common procedures in our group were meniscal procedures. However, it is well known that partial meniscectomy accelerates cartilage degeneration. The first line of treatment in older populations with meniscal lesions and coexisting cartilage defects is conservative treatment [24]. This may explain the prolonged time from the onset of symptoms to surgical treatment in our study, since most of the patients had undergone previous conservative treatment. However the mean visual analogue scale (VAS) score was 5.4, which can lead to great dysfunction in daily activities; therefore, it seems that such a long period of awaiting surgical treatment (44 months) may be too long for patients to bear. In our study, we found that the McMurray and Thessaly tests were the most sensitive in detecting medial meniscus lesions, with 85-87% sensitivity. Even though [PERSON] [13] in his original work described a clunk during knee motion, over the years various modifications have been introduced to the test, including the onset of pain or adding valgus and varus force to the knee. In our study we have shown a higher sensitivity of the McMurray test in detecting medial meniscus lesions than in the previously published papers [25; 26]. Such a high sensitivity in our results may be an effect of the preference of the examining surgeon for performing the McMurray test; however, the previously published papers showed that experience in performing this particular test plays no role in the diagnostic accuracy of the test [25], and therefore it seems an appropriate test to incorporate in the routine examination of patients. Most of the published literature has shown that the sensitivity of the McMurray test is lower for the lateral meniscus than for the medial meniscus [25; 27; 28]. Our results confirm this finding; however, the paper published by [PERSON] et al. suggests that the sensitivity of the McMurray test is increased for the lateral meniscus [15]. In 2005 a novel diagnostic test for meniscal tears was introduced [15] that was suggested to show higher sensitivity and specificity. According to [PERSON] et al. [15], a higher sensitivity in detecting lateral meniscus tears has been one of the most important findings of that test. However, our results and data published previously in literature oppose these findings [29], showing in fact a decreased sensitivity of the Thessaly test for the lateral meniscus. This divergence might be due to the fact that the Thessaly test is a dynamic examination in which the patient is actively involved and has to perform several rapid movements of the limb while bearing weight. In our study, we found a significant dependence of the diagnostic accuracy of the test in relation to the extension lag of the knee joint (\(p=0.012\)). The Thessaly test was also the only test showing a dependence on prior physiotherapy (\(p=0.005\)). These findings may contribute to understanding the gross divergence of data related to the Thessaly test. The Apley test was primarily designed in order to distinguish meniscal lesions from other intraarticular pathologies. However, our results differed from other publications in regard to sensitivity and specificity of the Apley test, finding both to be lower than in the previously published papers [15; 28]. In a paper published by [PERSON] et al. [28], the exclusion criteria included osteoarthritis changes in the joint. In our study we tried to answer the question of whether chondral lesions influence the diagnostic accuracy of physical examinations of meniscal lesions. We found that all of the tests were influenced by osteoarthritis changes in the knee joint with increasing sensitivity and decreasing specificity in higher-grade cartilage defects.