[Magnetic resonance imaging in the diagnosis of intra-articular lesions of the knee]. / Prínos MRI v diagnostike intraartikulárnych lézií kolenného klbu.

PURPOSE OF THE STUDY: Magnetic resonance imaging (MRI) has the highest sensitivity of all methods for the diagnosis of intra-articular knee injuries. In spite of this, its benefit for the decision-making algorithm is questionable. The aim of this study was to evaluate the real situation in our regional conditions. MATERIAL AND METHODS: The medical records of the patients who underwent knee arthroscopy in 2008 and 2009, and had pre-operative MRI examination, were retrospectively reviewed. The group included 92 patients (46 women and 46 men; average age, 41.7 years) of whom 49 had knee injury in their medical history. RESULTS: In medial meniscus (MM) injuries, the MRI examination had a sensitivity of 0.92 and a specificity of 0.44, and the congruence of MRI and arthroscopic findings was 0.73. In lateral meniscus (LM) tears, the values were 0.70 for sensitivity, 0.81 for specificity and 0.87 for congruence. In injury to the anterior cruciate ligament (ACL), MRI sensitivity was 0.66, specificity was 0.85 and congruence was 0.79. In evaluation of articular chondral lesions, the values were 0.45 for sensitivity, 0.87 for specificity and 0.60 for congruence. DISCUSSION: In our examination of knee structures for MM, LM, ACL and cartilage injuries, the diagnostic value of MRI was lowest for cartilage damage, with sensitivity being only 0.45. This was in agreement with the findings of other authors. Although this fact is known, our arthroscopic findings in patients with no MRI evidence of injury were very high: 22 knees with grade III or grade IV chondral lesions. Therefore, MRI examination is not considered to be sensitive enough to replace arthroscopy in the diagnosis of cartilage injuries. MRI examination is most frequently indicated in suspected meniscal damage. Its sensitivity reported in the literature varies; generally, it is about 0.90 in MM injuries, and about 0.75 in LM lesions, and this is in agreement with our results. However, in view of our previous experience, the high sensitivity of MRI in the diagnosis of MM lesions was an unexpected finding. A detailed statistical analysis showed that its high value was at the expense of a relatively high negative positivity (0.56) and a low predictive value of the positive test (0.65). In LM injuries these values were even worse: in addition to low sensitivity (0.70), the predictive value of the positive test was only 0.50. In the diagnosis of ACL injuries, MRI examination is reported to have a high sensitivity ranging from 0.85 to 0.90. This study showed poorer results; sensitivity was 0.66 and the predictive value of the positive test was 0.62. For injuries in which the orthopaedist is sure about the diagnosis and indicates arthroscopy, it is doubtful to indicate also MRI examination. This should be reserved for clinical presentations that are not clear, for post-operative conditions, serious knee injuries or combined injuries. However, patients with chronic problems and unclear clinical presentations should benefit from MRI examination which can make the diagnosis more accurate and thus reduce the number of arthroscopic procedures done entirely for diagnostic purposes. CONCLUSIONS: There is no consensus regarding the role of MRI in the diagnosis of intra-articular lesions of the knee. To a certain extent, its use is related to local conditions. It can be concluded that MRI examination is not currently as important for the diagnosis of knee injuries as expected by both medical and lay communities.

[Acute injuries of lateral ankle joint ligaments]. / Akútne poranenia laterálneho väzivového aparátu clenkového klbu.

Acute injuries of the lateral ankle ligaments are one of the most common form of injury involving the musculoskeletal apparatus. Treatment usually range from cast immobilisation or acute surgical repair to functional rehabilitation. The aim of our study was to evaluate the incidence of different grades of acute injuries of lateral ligaments of the ankle joint in our patients group and to compare the results of non surgical versus surgical treatment of third grade injuries. 3148 patients were treated for acute lateral ankle sprain in a period of 5 years at our department. Each patient had stress X-ray of the ankle for evaluation of instability at the first visit. From the 234 patients with third grade injury, 39 were enrolled in our study with non surgical treatment and 18 with surgical treatment. Each group was divided regarding to the age in two subgroups. Functional outcome was evaluated 12 and 24 months after injury with AOFAS clinical rating scale and Sports Ankle Rating System--Single Assessment Numeric Evaluation. Statistical analysis was done with Pearson's Chi quadrate test with P < 0.05. First grade injury was present in 62%, second grade in 31% and only 7% of the patients had third grade injury of the lateral ankle ligaments. Further only third grade injuries were studied. Statistically significant better results were seen in patients under the age of 25, in the patient group with surgical treatment compared to patients over 25 years of age. Also statistically significant better results were seen in patient with surgical treatment to non surgical treatment in each age group. No significant difference was observed in the non surgical treatment group regarding to age. Although the injuries of the ankle ligaments belong to the most common injuries of the musculoskeletal system, there is no consensus in the treatment of such disorders. Our experiences and the results of our study show, that surgical treatment in indicated cases provides better results in residual pain and instability of the ankle joint after acute injury of the lateral ankle ligaments.;

Effects of static magnetic field and pulsed electromagnetic field on viability of human chondrocytes in vitro.

Effects of electromagnetic fields (EMFs) on human cell lines were described in numerous studies, but still many questions remain unanswered. Our experiment was designed with the aim of studying the effects of EMFs on the metabolic activity of chondrocytes in vitro. Human chondrocyte in vitro cultures, cultured in medium supplemented with 20 % fetal calf serum, were exposed to static magnetic field (SMF) (intensity of 0.6 T) and pulsed electromagnetic fields (PEMF) (21.2 MHz period of 15 ms, burst duration of 2 ms, amplification 3 dBm (0.1 V) and maximum output of 250 W) continually for 72 h. After the exposure, viability was determined using the MTT test and compared with a non-exposed control culture. As compared to the control sample the exposure to SMF resulted in a statistically significant increase (p 0.001) in viability. However, the increase of viability after PEMF exposure was not significant. This could be due to the frequency dependent effect on human cells. The experiments demonstrated that magnetic fields, using the above parameters, have a positive effect on the viability of human chondrocytes cultured in vitro.