Department of Orthopaedic Surgery, West China Hospital, Sichuan University, Chengdu, China.
Bone Joint J. 2022 Feb;104-B(2):193-199. doi: 10.1302/0301-620X.104B2.BJJ-2021-1385.R1.
This study aimed to use intraoperative free electromyography to examine how the placement of a retractor at different positions along the anterior acetabular wall may affect the femoral nerve during total hip arthroplasty (THA) when undertaken using the direct anterior approach (THA-DAA).
Intraoperative free electromyography was performed during primary THA-DAA in 82 patients (94 hips). The highest position of the anterior acetabular wall was defined as the "12 o'clock" position (middle position) when the patient was in supine position. After exposure of the acetabulum, a retractor was sequentially placed at the ten, 11, 12, one, and two o'clock positions (right hip; from superior to inferior positions). Action potentials in the femoral nerve were monitored with each placement, and the incidence of positive reactions (defined as explosive, frequent, or continuous action potentials, indicating that the nerve was being compressed) were recorded as the primary outcome. Secondary outcomes included the incidence of positive reactions caused by removing the femoral head, and by placing a retractor during femoral exposure; and the incidence of femoral nerve palsy, as detected using manual testing of the strength of the quadriceps muscle.
Positive reactions were significantly less frequent when the retractor was placed at the ten (15/94; 16.0%), 11 (12/94; 12.8%), or 12 o'clock positions (19/94; 20.2%), than at the one (37/94; 39.4%) or two o'clock positions (39/94; 41.5%) (p < 0.050). Positive reactions also occurred when the femoral head was removed (28/94; 29.8%), and when a retractor was placed around the proximal femur (34/94; 36.2%) or medial femur (27/94; 28.7%) during femoral exposure. After surgery, no patient had reduced strength in the quadriceps muscle.
Placing the anterior acetabular retractor at the one or two o'clock positions (right hip; inferior positions) during THA-DAA can increase the rate of electromyographic signal changes in the femoral nerve. Thus, placing a retractor in these positions may increased the risk of the development of a femoral nerve palsy. Cite this article: 2022;104-B(2):193-199.
本研究旨在使用术中游离肌电图检查在直接前入路(THA-DAA)全髋关节置换术(THA)中,当髋臼拉钩放置在髋臼前壁的不同位置时,对股神经的影响。
对 82 例(94 髋)初次行 THA-DAA 的患者进行术中游离肌电图检查。当患者仰卧时,将髋臼前壁的最高位置定义为“12 点”(中间位置)。髋臼显露后,髋臼拉钩依次置于 10 点、11 点、12 点、1 点和 2 点(右侧髋关节;从上到下的位置)。在每个位置放置拉钩时监测股神经的动作电位,并记录阳性反应的发生率(定义为爆发性、频繁性或连续性动作电位,表明神经受压),作为主要结局。次要结局包括去除股骨头和暴露股骨时放置拉钩引起的阳性反应发生率;以及使用股四头肌力量的手动测试检测到的股神经麻痹发生率。
当拉钩置于 10 点(15/94;16.0%)、11 点(12/94;12.8%)或 12 点(19/94;20.2%)时,阳性反应明显较 1 点(37/94;39.4%)或 2 点(39/94;41.5%)时少(p<0.050)。当去除股骨头(28/94;29.8%)和在暴露股骨时将拉钩放置在股骨近端周围(34/94;36.2%)或股骨内侧(27/94;28.7%)时,也会出现阳性反应。术后,所有患者股四头肌力量均无减弱。
在 THA-DAA 中,将髋臼前拉钩置于 1 点或 2 点(右侧髋关节;下方位置)时,可增加股神经肌电图信号变化率。因此,将拉钩置于这些位置可能会增加股神经麻痹的发生风险。引用本文:2022;104-B(2):193-199。