Institute for Global Orthopaedics and Traumatology, Department of Orthopaedic Surgery, University of California, San Francisco, USA.
Department of Orthopaedics, Muhimbili University of Health and Allied Sciences, Muhimbili Orthopaedic Institute, Dar es Salaam, Tanzania.
Injury. 2021 Apr;52(4):982-987. doi: 10.1016/j.injury.2020.10.078. Epub 2020 Oct 17.
This investigation develops a predictive model for loss of alignment (LOA) following fixation of open tibia fractures.
PATIENTS/METHODS: An analysis was performed of adults with diaphyseal open tibia fractures randomized to intramedullary nailing (IMN) or external fixation (EF) followed at 6, 12, 24, and 52 weeks postoperatively. Demographic data were collected at baseline. Pre-injury and follow-up EuroQol 5-Dimensions (EQ-5D) and pain score were measured. Radiographs, taken postoperatively and in follow-up, were assessed for coronal and sagittal angulation, and used to calculate the modified Radiographic Union Scale for Tibia fractures (mRUST). LOA was defined as an increase in angulation >5° by one year follow-up. Fracture comminution was defined using AO/OTA classification. Putative risk factors were assessed for association with LOA using bivariate logistic regression. Adjusted associations with LOA were estimated using multivariable logistic regression and marginal analysis.
Analyses included 129 patients (70 IMN, 59 EF), majority male, of mean age 33 years (range 17.7-73) and body mass index (BMI) 25.2 (range 15.5-45.1), with 48% Type A, 41% Type B, and 11% Type C fractures (AO/OTA classification). The likelihood of LOA with EF increased with greater fracture comminution; 45.21% (p<0.001), 77.50% (p<0.001), and 100% LOA for Type A, B, and C fractures respectively. Relative risk of LOA for EF compared to IMN was 3.87 (95% CI 1.36, 11.02), 3.75 (95% CI 1.77, 7.92), and 5.76 for Type A, B, and C fractures, respectively. Compared to patients who lost alignment, patients without LOA had improved fracture healing (p = 0.003) and higher EQ-5D scores (p = 0.03) at one year.
Increasing age and BMI are associated with LOA and segmental fracture amplifies the protective effect of IMN versus EF. The importance of LOA as a surrogate outcome after operative treatment of open tibial fractures is supported by its association with inferior radiographic and functional patient outcomes.
本研究旨在建立一种预测开放性胫骨骨折固定后对线丢失（LOA）的模型。
患者/方法：对接受髓内钉（IMN）或外固定（EF）治疗的成人骨干开放性胫骨骨折患者进行分析，术后分别在 6、12、24 和 52 周进行随访。基线时收集患者的人口统计学数据。测量患者术前和随访时的 EuroQol 5 维度（EQ-5D）和疼痛评分。术后和随访时拍摄的 X 线片评估冠状面和矢状面成角，并用于计算改良的胫骨骨折放射学愈合评分（mRUST）。LOA 定义为 1 年后成角增加>5°。骨折粉碎程度采用 AO/OTA 分类。使用双变量逻辑回归评估可能的危险因素与 LOA 的相关性。使用多变量逻辑回归和边缘分析估计 LOA 的调整后相关性。
纳入了 129 名患者（70 名 IMN，59 名 EF），主要为男性，平均年龄 33 岁（17.7-73 岁），体重指数（BMI）为 25.2（15.5-45.1），48%为 A 型，41%为 B 型，11%为 C 型骨折（AO/OTA 分类）。随着骨折粉碎程度的增加，EF 发生 LOA 的可能性增加；A 型、B 型和 C 型骨折的 LOA 发生率分别为 45.21%（p<0.001）、77.50%（p<0.001）和 100%（p<0.001）。与 IMN 相比，EF 发生 LOA 的相对风险为 3.87（95%CI 1.36，11.02）、3.75（95%CI 1.77，7.92）和 A、B、C 型骨折分别为 5.76。与 LOA 患者相比，无 LOA 患者的骨折愈合情况更好（p=0.003），1 年时 EQ-5D 评分更高（p=0.03）。
年龄和 BMI 的增加与 LOA 有关，节段性骨折会放大 IMN 与 EF 相比的保护作用。LOA 作为开放性胫骨骨折术后替代结局的重要性，与患者的放射学和功能结局较差有关。
