Sonoda Kazuhiko, Motomura Goro, Ikemura Satoshi, Kubo Yusuke, Yamamoto Takuaki, Nakashima Yasuharu
Department of Orthopaedic Surgery, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
Department of Orthopaedic Surgery, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
JB JS Open Access. 2017 Mar 23;2(1):e0013. doi: 10.2106/JBJS.OA.16.00013. eCollection 2017 Mar 30.
Subchondral insufficiency fracture of the femoral head (SIF) occurs infrequently in young adults. As the collapsed SIF lesion is usually located at the anterior portion of the femoral head, young adults with SIF are considered to be candidates for transtrochanteric anterior rotational osteotomy, similar to patients with osteonecrosis of the femoral head (ON). In the present study, we assessed the clinical and radiographic results of anterior rotational osteotomy for the treatment of SIF as compared with ON.
We retrospectively reviewed 28 consecutive patients who underwent anterior rotational osteotomy for the treatment of unilateral SIF (7 patients) or unilateral ON (21 patients). The mean duration of follow-up was 3.7 years (range, 2.0 to 6.2 years). Clinical and radiographic assessments were performed with use of the Harris hip score (HHS), sequential radiographs, and single-photon emission computed tomography/computed tomography (SPECT/CT) with Tc-hydroxymethylene diphosphonate performed 5 weeks after surgery.
The mean HHS (and standard deviation) in the SIF group improved significantly from 51.6 ± 11.7 preoperatively to 91.9 ± 7.1 at 1 year after surgery and to 96.9 ± 3.8 at the time of the latest follow-up (p = 0.0010 and 0.0002, respectively). Similarly, the mean HHS in the ON group improved significantly from 52.4 ± 13.7 preoperatively to 80.7 ± 10.0 at 1 year after surgery and to 88.2 ± 12.6 at the time of the latest follow-up (p < 0.0001 for both). The HHS was significantly higher in the SIF group than in the ON group at 1 year after surgery (p = 0.019), but there was no significant difference between the groups at the time of the latest follow-up (p = 0.10). A postoperative intact ratio (calculated as the intact area of the femoral head divided by the weight-bearing area of the acetabulum on an anteroposterior radiograph) of >80% was achieved in association with smaller femoral neck-shaft varus angles in the SIF group (10.0° ± 4.2°) as compared with the ON group (15.3° ± 8.2°). Postoperative progression of collapse at the anteriorly rotated subchondral lesion was observed in 5 patients (23.8%) in the ON group but no patients in the SIF group. SPECT/CT images showed that rate of increased tracer uptake at the collapsed lesions in the SIF group was significantly higher than that in the ON group (p < 0.0001).
The present study suggested that the absence of progression of collapse and a sufficient postoperative intact ratio without the need for marked varus realignment may be associated with favorable results following anterior rotational osteotomy for the treatment of SIF in young adults.
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
股骨头软骨下不全骨折（SIF）在年轻成年人中很少见。由于塌陷的SIF病变通常位于股骨头前部，SIF的年轻成年人被认为是转子间前旋转截骨术的候选者，类似于股骨头坏死（ON）患者。在本研究中，我们评估了与ON相比，前旋转截骨术治疗SIF的临床和影像学结果。
我们回顾性分析了28例连续接受前旋转截骨术治疗单侧SIF（7例）或单侧ON（21例）的患者。平均随访时间为3.7年（范围2.0至6.2年）。使用Harris髋关节评分（HHS）、系列X线片以及术后5周进行的锝-亚甲基二膦酸盐单光子发射计算机断层扫描/计算机断层扫描（SPECT/CT）进行临床和影像学评估。
SIF组的平均HHS（及标准差）从术前的51.6±11.7显著提高到术后1年的91.9±7.1，以及最近一次随访时的96.9±3.8（p分别为0.0010和0.0002）。同样，ON组的平均HHS从术前的52.4±13.7显著提高到术后1年的80.7±10.0，以及最近一次随访时的88.2±12.6（两者p均<0.0001）。术后1年时，SIF组的HHS显著高于ON组（p = 0.019），但在最近一次随访时两组之间无显著差异（p = 0.10）。与ON组（15.3°±8.2°）相比，SIF组获得了>80%的术后完整率（计算方法为股骨头完整面积除以前后位X线片上髋臼的负重面积），且股骨颈干角较小（10.0°±4.2°）。ON组有5例患者（23.8%）观察到前旋转软骨下病变处塌陷的术后进展，而SIF组无患者出现。SPECT/CT图像显示，SIF组塌陷病变处示踪剂摄取增加率显著高于ON组（p < 0.0001）。
本研究表明，对于年轻成年人SIF的治疗，前旋转截骨术后无塌陷进展且有足够的术后完整率而无需明显内翻矫正可能与良好结果相关。
治疗性III级。有关证据水平的完整描述，请参见作者须知。
