Tianjin Hospital, Tianjin University, Tianjin, China.
Tianjin Medical University, Tianjin, China.
Orthop Surg. 2022 Oct;14(10):2682-2691. doi: 10.1111/os.13436. Epub 2022 Sep 8.
Few studies have performed detailed ultrasound measurements of medial epicondyle-olecranon (MEO) ligament that cause the entrapment of ulnar nerve. This study aims to comprehensively evaluate dynamic ultrasonographic characteristics of MEO ligament and ulnar nerve for clinical diagnosis and accurate treatment of cubital tunnel syndrome (CuTS).
Thirty CuTS patients (CuTS group) and sixteen healthy volunteers (control group) who underwent ultrasound scanning from October 2016 to October 2020 were retrospectively collected, with 30 elbows in each group. Primary outcomes were thickness at six points, length and width of MEO ligament. Secondary outcomes were thickness of ulnar nerve under MEO ligament at seven parts and the cross-sectional area (CSA) of ulnar nerve at proximal end of MEO ligament (P ). The thickness of MEO ligament and ulnar nerve in different points of each group was compared by one-way ANOVA analysis with Bonferroni post hoc test, other outcomes were compared between two elbow positions or two groups using independent-samples t test.
Thickness of MEO ligament in CuTS group at epicondyle end, midpoint in transverse view, olecranon end, proximal end, midpoint in axial view, and distal end was 0.67 ± 0.31, 0.37 ± 0.18, 0.89 ± 0.35, 0.39 ± 0.21, 0.51 ± 0.38, 0.36 ± 0.25 at elbow extension, 0.68 ± 0.34, 0.38 ± 0.27, 0.77 ± 0.39, 0.32 ± 0.20, 0.48 ± 0.22, 0.32 ± 0.12 (mm) at elbow flexion, respectively. Compared with control group, they were significantly thickened except for proximal end at elbow flexion. MEO ligament thickness at epicondyle end and olecranon end was significantly larger than midpoint in two groups. No significant difference was found in length and width of MEO ligament among different comparisons. Ulnar nerve thickness at 5 mm proximal to MEO ligament (P , 3.25 ± 0.66 mm) was significantly increased than midpoint of MEO ligament (Mid), distal end of MEO ligament (D ), 5 mm (D ), 10 mm (D ) distal to MEO ligament at extension in CuTS group. Compared with control group, ulnar nerve thickness at P in CuTS group was significantly increased at extension position, at D and D was significantly decreased at flexion position. CSA of ulnar nerve at extension position (14.44 ± 4.65 mm ) was significantly larger than flexion position (11.83 ± 3.66 mm ) in CuTS group, and CuTS group was significantly larger than control group at two positions.
MEO ligament in CuTS patients was thickened, which compressed ulnar nerve and caused its proximal end swelling. Ultrasonic image of MEO ligament thickness was a significant indicator for CuTS and can guide surgeons in selecting the appropriate treatment.
很少有研究对导致尺神经卡压的内侧上髁-鹰嘴（MEO）韧带进行详细的超声测量。本研究旨在全面评估 MEO 韧带和尺神经的动态超声特征，为肘管综合征（CuTS）的临床诊断和准确治疗提供依据。
回顾性收集了 2016 年 10 月至 2020 年 10 月期间接受超声扫描的 30 例 CuTS 患者（CuTS 组）和 16 名健康志愿者（对照组），每组 30 个肘部。主要结局为 MEO 韧带六点处的厚度、长度和宽度。次要结局为伸肘和屈肘时 MEO 韧带下尺神经的厚度和 MEO 韧带近端（P ）处尺神经的横截面积（CSA）。采用单因素方差分析和 Bonferroni 事后检验比较两组各点的 MEO 韧带和尺神经厚度，采用独立样本 t 检验比较两种肘位或两组之间的其他结果。
CuTS 组伸肘时 MEO 韧带在髁突端、横切面中点、鹰嘴端、近端、矢状面中点和远端的厚度分别为 0.67±0.31、0.37±0.18、0.89±0.35、0.39±0.21、0.51±0.38、0.36±0.25，屈肘时分别为 0.68±0.34、0.38±0.27、0.77±0.39、0.32±0.20、0.48±0.22、0.32±0.12（mm）。与对照组相比，除了屈肘时的近端，其余各点均明显增厚。MEO 韧带在髁突端和鹰嘴端的厚度明显大于两组的中点。两组间 MEO 韧带的长度和宽度无明显差异。CuTS 组伸肘时 P 处（P ，3.25±0.66mm）比 MEO 韧带中点（Mid）、MEO 韧带远端（D ）、MEO 韧带 5mm（D ）、10mm（D ）处明显增厚。与对照组相比，CuTS 组伸肘时 P 处尺神经厚度明显增加，而屈肘时 D 和 D 处明显减少。CuTS 组伸肘时尺神经 CSA（14.44±4.65mm ）明显大于屈肘时（11.83±3.66mm ），且两组间均明显大于对照组。
CuTS 患者的 MEO 韧带增厚，压迫尺神经，导致其近端肿胀。MEO 韧带厚度的超声图像是 CuTS 的一个重要指标，可以指导外科医生选择合适的治疗方法。
