Kuyucu E, Ceylan H H, Surucu S, Erdil I, Kara A, Gulenc B G, Bulbul M, Erdil M
Medipol University, Department of Orthopaedics and Traumatology, Istanbul, Turkey.
Acta Chir Orthop Traumatol Cech. 2017;84(3):196-201.
PURPOSE OF THE STUDY Accurate radiographic measurements are crucial in treating hallux valgus (HV). This three-dimensional deformity should not be evaluated from one joint on one plane. However, in practice, surgeons measure the deformity only on transverse dorsoplantar radiographs. We determined the amount of error associated with positioning the foot incorrectly on radiographs. MATERIAL AND METHODS To simulate incorrect positions of the foot in radiographic evaluation, we designed an angled device that can move in transverse and frontal plane. In four patients with symptomatic HV, we took weight-bearing radiographs of the involved foot in seven different positions. These 28 radiographs were given identifying but meaningless labels. On each radiograph, six surgeons blinded to the position of the radiograph measured the HV angle (HVA) and the inter-metatarsal angle (IMA) and state the treatment plan according to five treatment options were given to participants. RESULTS Inter-observer agreement was high for measurements of HVA and IMA in all positions (interclass correlation coefficients, 0.96 and 0.88, respectively). However, intra-observer agreement was poor for HVA (intra-observer agreement, 0.17) but good for IMA (intra-observer agreement, 0.64). According to the measurements in different positions, intra-observer treatment choices revealed moderate results (ICC: 0.524). Clinical Relevance Radiographic measurements are very important on the treatment decisions of hallux valgus. The foot position can influence the measurement accuracy and can cause incorrect decisions. In this study, we evaluated the impact of foot positions on measurements of hallux valgus angle and inter-metatarsal angle. Additionally, we evaluated the incorrect foot positioning on treatment decisions. Moreover, we analyzed intra-observer and inter-observer agreements of these angles in various positions. CONCLUSIONS We recommend that measurements of IMA are more reliable than those of HVA for managing hallux valgus in terms of false weight bearing radiographs taken in different positions. Positional changes during foot radiographs could lead clinicians to perform incorrect HVA and IMA measurements. This could change the treatment option. HVA measurements were more affected with foot positioning. It is important to take full weight bearing foot radiographs in correct technique. Key words: hallux valgus, radiology, data accuracy.
研究目的 准确的影像学测量对于拇外翻（HV）的治疗至关重要。这种三维畸形不应仅从一个平面上的一个关节进行评估。然而，在实际操作中，外科医生仅在背跖位X线片上测量畸形。我们确定了在X线片上足部位置摆放不正确时所产生的误差量。
材料与方法 为了模拟X线评估中足部的不正确位置，我们设计了一种可在横向和额状面移动的成角装置。在4例有症状的HV患者中，我们在7个不同位置拍摄了患足的负重X线片。这28张X线片被赋予了可识别但无意义的标签。在每张X线片上，6名对X线片位置不知情的外科医生测量了HV角（HVA）和跖间角（IMA），并根据5种治疗方案陈述治疗计划。
结果 在所有位置上，HVA和IMA测量的观察者间一致性都很高（组内相关系数分别为0.96和0.88）。然而，观察者内HVA一致性较差（观察者内一致性，0.17），而IMA一致性良好（观察者内一致性，0.64）。根据不同位置的测量结果，观察者内治疗选择显示出中等结果（ICC：0.524）。
临床意义 影像学测量对拇外翻的治疗决策非常重要。足部位置会影响测量准确性，并可能导致错误决策。在本研究中，我们评估了足部位置对拇外翻角和跖间角测量的影响。此外，我们评估了不正确的足部位置对治疗决策的影响。而且，我们分析了这些角度在不同位置的观察者内和观察者间一致性。
结论 对于在不同位置拍摄的假负重X线片，我们建议在处理拇外翻时，IMA测量比HVA测量更可靠。足部X线片拍摄过程中的位置变化可能导致临床医生对HVA和IMA进行错误测量。这可能会改变治疗方案。HVA测量受足部位置影响更大。采用正确技术拍摄全负重足部X线片很重要。
拇外翻；放射学；数据准确性
