Orthopaedics and Trauma Surgery, Musculoskeletal Institute, 5th floor, Pierre-Paul-Riquet Hospital, 308, avenue de Grande-Bretagne, 31059 Toulouse, France.
Orthop Traumatol Surg Res. 2013 Sep;99(5):501-8. doi: 10.1016/j.otsr.2013.03.020. Epub 2013 Jun 22.
It is a well-known fact that slipped capital femoral epiphysis (SCFE) is one of the causes of premature hip osteoarthritis and anterior femoroacetabular impingement. But there are no reliable, published diagnostic methods to measure the residual deformity of slipped capital femoral epiphysis. We propose using the lateral view head-neck index (LVHNI) measurement on a specific lateral X-ray view of the hip for this purpose.
The LVHNI can detect and quantify the posterior translation of the femoral head and this index can be measured reliably.
A prospective radiography study was performed by three observers. The hip X-rays of patients who were being treated by arthroplasty for hip osteoarthritis (total hip replacement or hip resurfacing) between January 2010 and December 2011 were analyzed. The LVHNI, which quantifies the posterior translation of the femoral head, was measured on a lateral view of the hip in 45° flexion/45° abduction/30° external rotation. The presence of a pistol grip deformity on A/P X-rays was also assessed.
The analysis was performed on 131 hips in 120 patients having an average age of 61 years (range 37-91). The chosen LVHNI threshold of 9% resulted in a sensitivity of 89.1% (95% CI: 78.8%-95.5%) and a specificity of 82.4% (95% CI: 71.2%-89.7%) for detecting the presence of a pistol grip deformity. Twenty percent of the hips with no visible deformity on A/P X-rays had a pathological index value. The inter-observer reproducibility was good for the LHNI [intraclass correlation coefficient (ICC): 0.61; 95% CI: 0.51-0.71] and for detecting a pistol grip deformity (ICC: 0.74; 95% CI: 0.62-0.85). The intra-observer reproducibility was excellent for the LHNI (ICC: 0.78; 95% CI: 0.57-0.88) and the pistol grip deformity (ICC: 0.85; 95% CI: 0.74-0.92).
The LVHNI is a reliable and reproducible tool to identify deformities secondary to SCFE on specific lateral femoral neck X-rays. If the index value is greater than 9%, SCFE sequelae may be present. In addition, this study showed that 20% of hips with normal A/P X-rays had a pathological index.
Level IV, prospective diagnostic study without control group.
众所周知，股骨头骨骺滑脱（SCFE）是导致髋关节骨关节炎和前股骨髋臼撞击症的原因之一。但是，目前还没有可靠的、已发表的诊断方法来测量股骨头骨骺滑脱的残余畸形。我们提出使用髋关节特定外侧 X 射线的外侧头颈指数（LVHNI）测量来达到这个目的。
LVHNI 可以检测和量化股骨头的后移，并且这个指数可以可靠地测量。
进行了一项前瞻性放射学研究，由三位观察者进行。对 2010 年 1 月至 2011 年 12 月期间因髋关节骨关节炎（全髋关节置换或髋关节表面置换）而接受关节置换治疗的患者的髋关节 X 射线进行了分析。在 45°屈曲/45°外展/30°外旋的髋关节外侧视图上测量了 LVHNI，该指数量化了股骨头的后移。还评估了前后 X 射线上是否存在手枪柄畸形。
对 120 名患者的 131 髋进行了分析，平均年龄为 61 岁（范围 37-91 岁）。选择的 9% 的 LVHNI 阈值导致对存在手枪柄畸形的检测具有 89.1%（95%CI：78.8%-95.5%）的敏感性和 82.4%（95%CI：71.2%-89.7%）的特异性。20%的髋关节在前后 X 射线上没有可见的畸形，但指数值异常。LHNI 的观察者间可重复性良好[组内相关系数（ICC）：0.61；95%CI：0.51-0.71]，检测手枪柄畸形的可重复性也很好（ICC：0.74；95%CI：0.62-0.85）。LHNI（ICC：0.78；95%CI：0.57-0.88）和手枪柄畸形（ICC：0.85；95%CI：0.74-0.92）的观察者内可重复性均很好。
LVHNI 是一种可靠且可重复的工具，可用于识别特定外侧股骨颈 X 射线上继发于 SCFE 的畸形。如果指数值大于 9%，则可能存在 SCFE 后遗症。此外，本研究表明，20%的前后 X 射线正常的髋关节存在异常指数。
IV 级，无对照组的前瞻性诊断研究。
