MRI ASSESSMENT OF POPLITEUS TENDON VARIATIONS AND THEIR ASSOCIATION WITH LATERAL MENISCUS ABNORMALITIES IN ADULTS

Abstract

Background The popliteus tendon plays an important role in the stabilization of the posterolateral aspect of the knee joint. Some anatomic relationships exist between the popliteus tendon, the lateral meniscus, and the meniscopopliteal fascicles. There are some morphological variations in the popliteus tendon that are associated with abnormalities in the lateral meniscus and may be diagnosed by MRI.

Objectives To assess the morphologic changes of the popliteus tendon with MRI examination and its relationship to lateral meniscal lesions in adult population.

Methods The descriptive cross-sectional research was carried out in radiology units of selected tertiary care hospitals in Lahore. 96 patients were selected by using non-probability consecutive sampling technique and their knee MRI was performed. Morphological characteristics of popliteus tendon, meniscopopliteal fascicles, and lateral meniscal abnormalities including degeneration, Stoller signal intensity grade, tear type, and extrusion were identified with the help of MRIs. Data were analyzed by using statistical package for social sciences (SPSS) version 26. Descriptive statistics were computed and relationships among categorical variables were determined by the chi-square test. P value <0.05 was taken as statistically significant.

Results Mean age of participants was 40.53±13.67 years with age range being 18-63 years. Normal morphology of the popliteus tendon was observed in 55 (57.3%) cases, while 18 (18.8%) cases had accessory slip, 14 (14.6%) had bifid tendon and 9 (9.4%) had split tendons. Meniscal degeneration was present in 65 (67.7%) patients; Grade III Stoller signal intensity score was observed in 39 (40.6%) patients. Significant associations were observed between popliteus tendon morphology and degenerative changes of meniscus (χ²=24.914, df=3, p<0.001); Stoller signal intensity score (χ²=48.952, df=9, p<0.001); meniscal tear pattern (χ²=58.813, df=12, p<0.001); meniscal extrusion (χ²=42.784, df=3, p<0.001); and meniscocapsular separation (χ²=32.105, df=3, p<0.001).

Conclusion Significant correlations were observed between morphological differences of the popliteus tendon and different MRI results of the lateral meniscus. In the MRI analysis of lateral knee injury, consideration should be given to the evaluation of the morphology of the popliteus tendon and its accompanying structures. Further multicenter studies are needed to clarify their clinical significance.