Unité chirurgie rachis 1, Université Bordeaux CHU, 33076, Bordeaux, France.
Eur Spine J. 2011 Sep;20 Suppl 5(Suppl 5):681-5. doi: 10.1007/s00586-011-1936-x. Epub 2011 Aug 26.
It has become well recognised that sagittal balance of the spine is the result of an interaction between the spine and the pelvis. Knee flexion is considered to be the last compensatory mechanism in case of sagittal imbalance, but only few studies have insisted on the relationship between spino-pelvic parameters and lower extremity parameters. Correlation between the lack of lumbar lordosis and knee flexion has not yet been established.
A retrospective study was carried out on 28 patients with major spinal deformities. The EOS system was used to measure spinal and pelvic parameters and the knee flexion angle; the lack of lumbar lordosis was calculated after prediction of lumbar lordosis with two different formulas. Correlation analysis between the different measured parameters was performed.
Lumbar lordosis correlated with sacral slope (r = -0.71) and moderately with knee flexion angle (r = 0.42). Pelvic tilt correlated moderately with knee flexion angle (r = 0.55). Lack of lumbar lordosis correlated best with knee flexion angle (r = 0.72 and r = 0.63 using the two formulas, respectively).
Knee flexion as a compensatory mechanism to sagittal imbalance was well correlated to the lack of lordosis and, depending on the importance of the former parameter, the best procedure to correct sagittal imbalance could be chosen.
人们已经认识到脊柱矢状平衡是脊柱和骨盆相互作用的结果。膝关节屈曲被认为是矢状失衡的最后一种代偿机制，但只有少数研究强调了脊柱-骨盆参数与下肢参数之间的关系。腰椎前凸不足与膝关节屈曲之间的相关性尚未确定。
对 28 例严重脊柱畸形患者进行回顾性研究。EOS 系统用于测量脊柱和骨盆参数以及膝关节屈曲角度；通过两种不同公式预测腰椎前凸后，计算腰椎前凸不足。对不同测量参数之间的相关性进行分析。
腰椎前凸与骶骨倾斜度呈负相关（r = -0.71），与膝关节屈曲角度中度相关（r = 0.42）。骨盆倾斜与膝关节屈曲角度中度相关（r = 0.55）。腰椎前凸不足与膝关节屈曲角度相关性最好（分别用两种公式，r = 0.72 和 r = 0.63）。
膝关节屈曲作为矢状失衡的代偿机制与腰椎前凸不足有很好的相关性，根据前一参数的重要性，可以选择最佳的方法来纠正矢状失衡。
