Hospital for Special Surgery, 535 East 70th Street, New York, NY, 10021, USA.
Department of Orthopedics, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20251, Hamburg, Germany.
Arch Orthop Trauma Surg. 2021 Aug;141(8):1401-1409. doi: 10.1007/s00402-021-03807-1. Epub 2021 Feb 13.
Correct acetabular component positioning improves hip biomechanics, impingement free range of motion and may lead to a reduced risk of postoperative dislocation. The C-arm is a simple and cost-effective tool for THA in a supine position, however, evaluation of the images can be challenging due to parallax. The current study aimed to investigate whether a software app-based measurement technique can control acetabular component position and leg length in anterior THA.
Ninety-three patients with end-stage osteoarthritis aged 65.2 ± 9.6 years (range 30-86 years) were included in this prospective study. All patients underwent direct anterior THA using a Hana orthopedic surgery table. C-arm imaging and an iPad software app were used to determine intraoperative acetabular anteversion, inclination and leg length discrepancy. The app provides a measuring tool that is applied to intraoperative c-arm images. The intraoperative measurements were compared to the measurements of standard postoperative AP-pelvis radiographs.
Intraoperative software app-based anteversion measurements averaged 20.5° (range 16.0° to 24.0°) compared to 20.9° (range 14.7° to 25.6°) postoperatively. Mean intraoperative inclination was 40.5° (range 35° to 48°) compared to postoperative 40.7° (range 35° to 49°). Mean intraoperative leg length discrepancy was 0.9 mm (range - 4-5 mm) compared to postoperative 0.6 mm (range - 5-6 mm). A strong Pearson's correlation was observed between the intraoperative and postoperative measurements for anteversion (r = .701; P < .0001), inclination (r = .816; P < .0001) and leg length discrepancy (r = .542; P < .0001).
The software app used in the current study allowed for a simple and accurate measurement of intraoperative cup position and leg length in direct anterior THA.
正确的髋臼组件定位可改善髋关节生物力学，增加无撞击运动范围，并降低术后脱位的风险。C 臂是一种在仰卧位下进行全髋关节置换术的简单且具有成本效益的工具，但是由于视差，评估图像可能具有挑战性。本研究旨在探讨基于软件应用的测量技术是否可以控制前侧全髋关节置换术中髋臼组件的位置和下肢长度。
本前瞻性研究纳入了 93 例年龄为 65.2±9.6 岁（范围 30-86 岁）的终末期骨关节炎患者。所有患者均采用 Hana 骨科手术台行直接前路全髋关节置换术。使用 C 臂成像和 iPad 软件应用程序来确定术中髋臼前倾角、倾斜度和下肢长度差异。该应用程序提供了一种可应用于术中 C 臂图像的测量工具。将术中测量值与标准术后骨盆正位 X 线片的测量值进行比较。
与术后相比，术中基于软件应用的前倾角测量值平均为 20.5°（范围 16.0°至 24.0°）。术中平均倾斜度为 40.5°（范围 35°至 48°），术后为 40.7°（范围 35°至 49°）。术中下肢长度差异平均为 0.9mm（范围-4 至 5mm），术后为 0.6mm（范围-5 至 6mm）。术中与术后的前倾角（r=.701；P<.0001）、倾斜度（r=.816；P<.0001）和下肢长度差异（r=.542；P<.0001）之间存在很强的 Pearson 相关性。
本研究中使用的软件应用程序允许在直接前路全髋关节置换术中简单且准确地测量髋臼杯的位置和下肢长度。
