髌骨高度测量受髌骨位置和滑车发育不良的影响：对确定高位髌骨的意义
简介
这项纳入190例（99例髌骨不稳、91例对照）的MRI研究对比了单图像与双图像测量髌骨高度的方法，发现双图像测量的Caton-Deschamps比值和髌骨滑车指数均低于单图像测量，且单图像CDR与滑车发育不良（外侧滑车倾斜角、滑车沟角、外侧髌骨倾斜角）呈中度相关。临床含义：单图像CDR可能因髌骨位置影响而高估髌骨高度，尤其合并滑车发育不良时，建议采用双图像测…
英文摘要
PURPOSE: To evaluate the effect that patellar position has on patellar height (PH) measurements by looking at differences between 1-image and 2-image PH measurements and examining their correlation with trochlear dysplasia (TD). METHODS: Patients were identified between 2019 and 2022 who met criteria for either recurrent patellar instability or control evaluation without instability and underwent knee magnetic resonance imaging (MRI). PH was assessed on MRI using 1-image and 2-image Caton-Deschamps ratio (CDR) and patellotrochlear index (PTI). TD was evaluated on MRI via lateral trochlear inclination, lateral patellar inclination (LPI), and sulcus angle. Two-sample t-tests determined differences between study and control patients and paired t-tests determined differences between 1- and 2-image PH measurements. Pearson correlation analysis assessed the relationship between PH and TD measurements. RESULTS: A total of 190 patients were included (99 with patellar instability, 91 controls). MRI measurements of PH and TD were different between study and control groups (P < .05) except for PTI measurements. Full cohort analysis showed that significant differences were present for 1 versus 2-image measurements for both CDR and PTI (P < .001). The 1-image CDR had a moderate association with TD: lateral trochlear inclination (r = -0.38, P < .001), sulcus angle (r = 0.39, P < .001) and LPI (r = 0.47, P < .001). PTI measures had only a weak association with LPI. CONCLUSIONS: Two-image PH measurements produced lower assessments of PH than 1-image measures supporting the hypothesis that patellar position affects perceived PH on MRI. The 1-image CDR has a strong enough of an association with TD that it may not be a reliable measure of PH and may regularly overestimate PH assessments. LEVEL OF EVIDENCE: Level III, retrospective comparative case series.