Department of Orthopedics and Rehabilitation, University of Iowa, Iowa City, IA, USA.
Department of Biomedical Engineering, University of Iowa, Iowa City, IA, USA.
Foot Ankle Int. 2020 Sep;41(9):1106-1116. doi: 10.1177/1071100720933891. Epub 2020 Jul 10.
Posttraumatic osteoarthritis (PTOA) of the subtalar joint is a serious, disabling, and frequent complication following intra-articular calcaneal fractures (IACFs). Using plain radiographs to assess the subtalar joint for PTOA is imprecise and insensitive, hindering progress toward improving treatment and assessing outcomes. This study explored how low-dose weightbearing computed tomography (WBCT) can be used to provide reliable, quantitative 3D measures of subtalar joint space width (JSW) following IACF and correlated the 3D JSW with clinical outcomes.
After institutional review board approval, 21 patients (15 male; age, 28-70 years) who sustained IACFs and were treated with percutaneous surgical reduction underwent WBCT scans at follow-up visits 2 to 15 years (average, 7.8 years) after surgical treatment. Subtalar joint 3D JSW was computed after a semiautomated protocol was used to segment the talus and calcaneus from the WBCT data. Mean and minimum 3D JSW measurements were calculated and compared with Kellgren-Lawrence (KL) radiographic osteoarthritis grade, RAND-36 Physical (PCS) and Mental (MCS) Component Scores, and visual analog scale (VAS) pain scores. Spearman's rank correlation was used to detect the strength of association between variables, with significance set at < .05.
Mean 3D JSW values measured from WBCT for patients with IACFs ranged from 0.9 to 2.5 mm (1.7 0.4 mm) over the entire subtalar joint. Intra- and interrater reliabilities for the WBCT-based JSW measurement technique were 0.95 (95% CI, 0.91-0.97) and 0.97 (95% CI, 0.95-0.98), respectively. Mean and minimum 3D JSW values correlated inversely with VAS pain scores and KL grade ( < .05), particularly in central and posterior subtalar regions.
WBCT-based methods were used to quantify the preservation/loss of JSW in patients with IACFs, enabling more accurate, definitive measurement of subtalar PTOA. The results of this study demonstrate that WBCT can be utilized to objectively assess subtalar PTOA and help us to better understand how arthritic changes affect actual patient experience.
Level III, prognostic comparative study.
距下关节创伤后骨关节炎（PTOA）是一种严重的、致残的、常见的踝关节内跟骨骨折（IACF）后并发症。使用普通 X 光片评估距下关节的 PTOA 并不精确和敏感，这阻碍了治疗方法的改进和结果评估。本研究探讨了低剂量负重 CT（WBCT）如何用于提供 IACF 后可靠的、定量的 3D 距下关节间隙宽度（JSW）测量，并将 3D JSW 与临床结果相关联。
在机构审查委员会批准后，对 21 名男性（年龄 28-70 岁）患者进行了回顾性研究，这些患者因 IACF 而行经皮手术复位，并在手术治疗后 2 至 15 年（平均 7.8 年）进行了 WBCT 扫描。使用半自动协议将距骨和跟骨从 WBCT 数据中分割出来，计算距下关节的 3D JSW。计算并比较平均和最小 3D JSW 测量值与 Kellgren-Lawrence（KL）放射学骨关节炎分级、RAND-36 身体（PCS）和心理（MCS）分量评分以及视觉模拟量表（VAS）疼痛评分。采用 Spearman 秩相关分析来检测变量之间的关联强度，显著性水平设定为 <.05。
IACF 患者的 WBCT 测量的平均 3D JSW 值在整个距下关节范围内为 0.9 至 2.5 毫米（1.7 0.4 毫米）。基于 WBCT 的 JSW 测量技术的内部和组间可信度分别为 0.95（95%CI，0.91-0.97）和 0.97（95%CI，0.95-0.98）。平均和最小 3D JSW 值与 VAS 疼痛评分和 KL 分级呈负相关（ <.05），尤其是在距下关节的中央和后区。
基于 WBCT 的方法用于量化 IACF 患者 JSW 的保留/丢失情况，从而能够更准确、明确地测量距下 PTOA。本研究结果表明，WBCT 可用于客观评估距下 PTOA，并帮助我们更好地了解关节炎变化如何影响实际患者的体验。
III 级，预后比较研究。
