만성 무릎관절 통증환자에서 내측 반월상연골 손상과 관절 퇴행성 변화의 감별을 위한 99mTc-MDP 무릎관절 SPECT의 진단기준

Abstract

Purpose: In patients with chronic knee pain, the diagnostic performance of 99mTc-MDP Knee SPECT for internal derangement of knee is deteriorated due to degenerative changes. In this study, we tried to establish diagnostic criteria to differentiate medial meniscal injury (MMI) from degenerative change (DC) when the uptake is increased in medial compartment. Materials and Methods: A total of 49 knee SPECT of the patients with chronic (more than 3 months) knee pain, which showed increased 99mTc-MDP uptake in the medial compartment, were included in this study. The diagnosis was confirmed by arthroscopy. On knee SPECT, 3 diagnosic criteria for MMI were investigated. In Criterion Ⅰ, MMI was diagnosed when crescentic uptake was observed in the medial tibial plateau. In Criterion Ⅱ, crescentic uptake was further classified into anterior, mid, posterior, and diffuse patterns, according to the location of maximal uptake; and only crescentic mid, posterior, and diffuse patterns were diagnosed as MMI. In Criterion Ⅲ, MMI was diagnosed when medial tibial plateau showed higher activity then medial femoral condyle. The diagnostic performance of the 3 criteria was compared. Results: The sensitivity and specificity were 93% and 14% in Criterion Ⅰ, 89% and 38% in Criterion Ⅱ, and 75% and 67% in Criterion Ⅲ, respectively. Criterion Ⅲ had significantly improved diagnostic performance, especially, specificity. Conclusion: In this study, we established a practical diagnostic criterion to differentiate MMI from DC on knee SPECT. The result is helpful to improve the diagnostic value of knee SPECT as a screening test for chronic knee pain.