Y. H. Park, H. W. Cho, J. W. Choi, H. J. Kim, Department of Orthopaedic Surgery, Korea University Guro Hospital, Seoul, Korea.
G. W. Choi, Department of Orthopaedic Surgery, Korea University Ansan Hospital, Ansan, Korea.
Clin Orthop Relat Res. 2021 Jun 1;479(6):1265-1272. doi: 10.1097/CORR.0000000000001634.
Most intraarticular displaced calcaneal fractures are accompanied by bone defects after surgical treatment, but the concern about negative effects of bone defects has not been resolved yet owing to the few studies on this issue. Therefore, studies on volumetric changes in bone defects over time and the correlation between postoperative outcomes and residual bone defects will be helpful to address the controversy on the necessity of bone grafting in bone defects of calcaneal fractures.
QUESTIONS/PURPOSES: (1) Do bone defects change in size in the first year after surgical treatment of displaced intraarticular calcaneal fractures? (2) Does the size of residual bone defects correlate with postoperative radiographic or clinical outcomes?
Between 2015 and 2019, 99 patients with displaced intraarticular calcaneal fractures visited the investigators' institution, of whom 95 received surgical treatment. Of the patients treated with surgery, 25% (24 of 95) did not undergo open reduction and internal fixation via an extensile lateral approach, and 19% (18 of 95) had multiple fractures, bilateral fractures, open fractures, or a history of previous surgery on the calcaneus; all of these patients were excluded. During the study period, CT was routinely performed for calcaneal fractures immediately after and 12 months after the surgery, but 6% (6 of 95) of the patients had insufficient CT data due to loss to follow-up before 12 months or other reasons, leaving 47 patients for evaluation in this retrospective study. Fractures were fixed with plate and screws, and bone grafting was not performed in all patients. To answer our first question, which was on the changes in bone defects over time, volumetric measurements of the bone defect were performed using CT via the ITK-SNAP software. The percentage of volumetric change was calculated as a fraction of the volumetric change over 12 months from the initial volume. The percentage of the residual bone defect was calculated as a fraction of the volume of the residual bone defect relative to the volume of the entire calcaneus. To answer our second question, which was on the correlation between residual bone defects and postoperative outcomes, we assessed the Böhler angle, Gissane angle, calcaneal height, Olerud-Molander Ankle Score (OMAS), and VAS score for pain and compared these parameters with the size of the residual bone defect using the Pearson correlation coefficient. The OMAS and VAS scores for pain were evaluated and recorded during patient visits, and we obtained the scores through a chart review. All volumetric measurements and radiographic evaluations were performed by two orthopaedic surgeons, and the intraobserver and interobserver reliability were assessed using the intraclass correlation coefficient.
The mean volume of the bone defect measured using CT was 4 ± 3 cm3 immediately after surgery and 1 ± 1 cm3 12 months after surgery. During the first 12 months after surgery, the mean volume of the bone defect was reduced by 77% (95% confidence interval 73% to 80%). The mean residual bone defect in the entire calcaneus was 2% (95% CI 1% to 2%), and none of the postoperative outcomes were correlated with the residual bone defect.
As bone defects substantially resolve without treatment, surgeons do not need to use bone graft for the surgical treatment of displaced intraarticular calcaneal fractures. Future studies that include patients who underwent bone grafting for the treatment of calcaneal fractures are needed to confirm our findings and to further investigate whether bone grafting has additional benefits for the recovery of bone defects.
Level III, therapeutic study.
大多数关节内移位跟骨骨折在手术后都伴有骨缺损，但由于对此问题的研究较少，因此对于骨缺损的负面影响仍存在争议。因此，研究骨缺损随时间的体积变化以及术后结果与残余骨缺损之间的相关性，将有助于解决跟骨骨折骨缺损是否需要植骨的争议。
问题/目的：（1）关节内移位跟骨骨折手术后的第一年，骨缺损的大小是否会发生变化？（2）残余骨缺损的大小与术后影像学或临床结果是否相关？
在 2015 年至 2019 年期间，99 例关节内移位跟骨骨折患者就诊于研究者所在机构，其中 95 例接受了手术治疗。在接受手术治疗的患者中，25%（24/95）未行外侧扩展入路切开复位内固定，19%（18/95）存在多处骨折、双侧骨折、开放性骨折或既往有跟骨手术史；所有这些患者均被排除在外。在研究期间，所有患者在手术后即刻和 12 个月时均行 CT 检查，但由于在 12 个月之前失访或其他原因，6%（6/95）的患者 CT 数据不足，因此，在这项回顾性研究中，47 例患者可用于评估。骨折采用钢板和螺钉固定，所有患者均未进行植骨。为了回答我们的第一个问题，即骨缺损随时间的变化，我们使用 ITK-SNAP 软件通过 CT 对骨缺损进行了容积测量。体积变化百分比通过初始体积的 12 个月内的体积变化分数计算得出。残余骨缺损百分比通过残余骨缺损的体积相对于整个跟骨体积的分数计算得出。为了回答我们的第二个问题，即残余骨缺损与术后结果的相关性，我们评估了 Böhler 角、Gissane 角、跟骨高度、Olerud-Molander 踝关节评分（OMAS）和疼痛视觉模拟评分（VAS），并使用 Pearson 相关系数比较了这些参数与残余骨缺损的大小。OMAS 和疼痛 VAS 评分在患者就诊时进行评估和记录，我们通过病历回顾获得评分。所有容积测量和影像学评估均由两名骨科医生进行，使用组内相关系数评估了观察者内和观察者间的可靠性。
手术后即刻 CT 测量的骨缺损平均体积为 4±3cm3，术后 12 个月时为 1±1cm3。术后 12 个月内，骨缺损的平均体积减少了 77%（95%置信区间 73%至 80%）。整个跟骨的平均残余骨缺损为 2%（95%CI 1%至 2%），术后结果均与残余骨缺损无关。
由于骨缺损在不治疗的情况下会明显消退，因此外科医生在治疗关节内移位跟骨骨折时无需使用植骨。需要对接受植骨治疗跟骨骨折的患者进行进一步研究，以证实我们的发现，并进一步研究植骨是否对骨缺损的恢复有额外的益处。
III 级，治疗性研究。
