Introduction:Knee injuries are common in athletes, recreationists, and other people in their everyday activities.Objective:The study is aimed at establishing the validity of clinical findings, MRI and diagnostic arthroscopy of the knee in ACL, PCL, medial or lateral ligament lesions.Methods:The prospective research involved 63 inpatients at the Traumatology Clinic in Banja Luka- Niš between 1 January 2011 and 1 June 2012.Results:When clinically examining the ACL and based on the calculated post-test probability amounting to (LR+) = 0.8017, we conclude that there is a considerable probability (80.17%) that a patient with an arthroscopically diagnosed ACL lesion will have the same lesion diagnosed by MRI. The post-test probability following the clinical examination of the medial meniscus and amounting to (LR+) = 0.6943 suggests that there is a considerable probability (69.43%) that an arthroscopically diagnosed lesion of the medial meniscus will also be diagnosed by MRI. On the basis of the clinical examination of the lateral meniscus in the examined sample and calculated post-test probability amounting to (LR+) = 0.6346, we conclude that there is a considerable difference (63.46%) between the diagnostic arthroscopy and MRI of lateral meniscus lesions.Conclusion:Arthroscopic examination of the knee is a more valuable method than diagnosis by MRI and clinical examination for detecting lesions of the ACL, PCL, medial and lateral meniscus.

Introduction: The knee joint has a unique anatomical structure in the human body. The localization between the two longest bones in the human body – femur, and tibia – makes it prone to injuries, trauma, and other pathologies. Clinical examination of the joint is still the primary method in evaluating the condition of the patient's knee. The study aims to determine the diagnostic accuracy of clinical examination and magnetic resonance (MR) in assessing chondral lesions of knee joint using arthroscopy as a reference standard.Patients and methods: The examination was conducted on 94 patients (58 males and 36 females) with knee injuries. Clinical examination indicated a primary chondral lesion of knee cartilage in eight patients (five men and three women), with an average age of 45.75. Besides the clinical examination, the diagnostics were performed using MR imaging by Siemens of 0.5 Tesla, and arthroscopy was performed using Storz arthroscope.Results: Our research has generated the following values of clinical and MR results for chondral lesions: Sensitivity (Se) = 12.5%, Specificity (Sp): could not be calculated, Positive Predictive Value (PPV) = 100%, Negative Predictive Value (NPV) = 0% and Accuracy (ACC) = 12.5%. The accuracy of clinical and intraoperative results for chondral lesion was: Se =100%, Sp: could not be calculated, PPV = 100%, NPV: could not be calculated, and ACC = 100%. MR imaging and arthroscopy findings of chondral lesion showed: Se = 100%, Sp = 0%, PPV = 12.5%, NPV: could not be calculated and ACC = 12.5%. In comparing the clinical sign and MRand intraoperative result, Positive Predictive Value for patients with chondral lesion was maximal (100%), while comparing MR with the intraoperative result, Positive Predictive Value was 12.5%. In comparison between clinical sign and intraoperative results, the accuracy for patients with chondral lesion was 100%, while comparing the clinical sign with MR result and MR with the intraoperative result, the accuracy was 12.5%.Conclusion: Our examinations have shown that MR examination is not currently as valid for diagnosing injury of chondral cartilage of knee as the medical community or patients have anticipated it.