Näslund Jan, Waldén Markus, Lindberg Lars-Göran
Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Am J Sports Med. 2007 Oct;35(10):1668-73. doi: 10.1177/0363546507303115. Epub 2007 Jun 13.
Anterior knee pain without clinical and radiologic abnormalities has primarily been explained from a purely structural view. A recently proposed biologic and homeostatic explanation questions the malalignment theory. No objective measurement of the pathophysiology responsible for changes in local homeostasis has been presented.
Flexing the knee joint interferes with the perfusion of the patellar bone in patellofemoral pain syndrome.
Case control study; Level of evidence, 4.
Pulsatile blood flow in the patella was measured continuously and noninvasively using photoplethysmography. Measurements were made with the patient in a resting position with knee flexion of 20 degrees and after passive knee flexion to 90 degrees. In total, 22 patients with patellofemoral pain syndrome were examined bilaterally, and 33 subjects with healthy knees served as controls.
The pulsatile blood flow in the patient group decreased after passive knee flexion from 20 degrees to 90 degrees (systematic change in position, or relative position [RP] = -0.32; 95% confidence interval for RP, -0.48 to -0.17), while the response in the control group showed no distinct pattern (RP = 0.17; 95% confidence interval for RP, -0.05 to 0.31). The difference between the groups was significant (P = .0002). The median change in patients was -26% (interquartile range, 37).
Pulsatile patellar blood flow in patellofemoral pain syndrome patients is markedly reduced when the knee is being flexed, which supports the previous notion of an ischemic mechanism involved in the pathogenesis of this pain syndrome.
无临床及影像学异常的前膝痛主要从单纯的结构角度进行解释。最近提出的生物学和稳态学解释对排列不齐理论提出了质疑。目前尚未有针对导致局部稳态变化的病理生理学的客观测量方法。
膝关节屈曲会干扰髌股疼痛综合征中髌骨的血液灌注。
病例对照研究；证据等级，4级。
使用光电容积描记法连续、无创地测量髌骨的搏动性血流。测量时患者处于休息位，膝关节屈曲20度，以及被动膝关节屈曲至90度后进行。总共对22例双侧髌股疼痛综合征患者进行了检查，33例膝关节健康的受试者作为对照。
患者组被动膝关节从20度屈曲至90度后，搏动性血流减少（位置的系统性变化，或相对位置[RP] = -0.32；RP的95%置信区间为-0.48至-0.17），而对照组的反应无明显规律（RP = 0.17；RP的95%置信区间为-0.05至0.31）。两组间差异有统计学意义（P = .0002）。患者的中位变化为-26%（四分位间距，37）。
髌股疼痛综合征患者膝关节屈曲时，髌骨搏动性血流明显减少，这支持了先前关于该疼痛综合征发病机制中存在缺血机制的观点。
