Delaunay C
Clinique de l'Yvette, 43, route de Corbeil, 91160 Longjumeau Cedex, France.
Rev Chir Orthop Reparatrice Appar Mot. 2000 Sep;86(5):482-90.
The dynamic study of the patello-femoral joint is of outstanding interest in unexplained anterior knee pain syndrome. Accuracy of information provided by video-arthroscopy is of concern due to its technical conditions. Serum inflow favors the natural patellar tendency to shift laterally (mean value, 7 degrees ). Absence of active quadriceps muscle contraction under anesthesia and use of a tourniquet act conversely. The aim of this study conducted in less than 40 year-old patients, was to correlate retrospectively arthroscopic evaluation of patello-femoral tracking and trochlear centralization measured during conventional "inflow" procedure, with patella related pain syndrome and its outcome.
The study group included 116 knees in 66 male and 49 female patients (1 bilateral). Mean age at arthroscopy was 26 years (range, 12 to 40 years). According to pre-arthroscopic clinical data, knees were broken down into 3 study groups: Gr-T (Test, painless patella), 50 knees with meniscal and/or ligament injury: Gr-PRP (Patella Related Pain but no dislocation), 55 knees: Gr-DLC (patella DisLoCation), 11 knees. Arthroscopic technique was the following: general anesthesia, high-proximal pneumatic tourniquet (40mmHg), single antero-lateral portal and serum inflow by simple gravity (2m). The minimum flexion angle that was necessary to obtain de visu a perfect centralization of the patella dome into the trochlear groove was systematically measured before any arthroscopic procedure was performed.
Average value of the Flexion Angle providing perfect Centralization (FAC) in the "serum inflow" arthroscopic situation was 39 degrees in Gr-T and 52 degrees in Gr-PRP; this difference was highly significant (p <.0001). Patella centralization could not be achieved despite maximum possible flexion in 5 of the 55 PRP-knees and in 9 of the 11 DLC-knees. FAC value > 65 degrees correlated significantly (chi2, p=0.0001) with patella related clinical symptoms (pain and instability, groups PRP + DLC) and indicated patellar maltracking. In the PRP-group, an "FAC value > 65 degrees" showed a low sensitivity (0.34), but high specificity and positive predictive value of 0.98 and 0.95, respectively.
Arthroscopic examination for patello-femoral tracking can provide measurable information on the FAC angle, that is reproducible under precise technical conditions. Its diagnostic value in unexplained anterior knee pain versus information provided by conventional imaging, and their respective effectiveness-risk and -cost relations could be the purpose of future prospective studies.
髌股关节的动态研究在不明原因的前膝痛综合征中具有突出的研究价值。由于视频关节镜检查的技术条件，其提供信息的准确性受到关注。血清流入有利于髌骨自然向外侧移位（平均值为7度）。麻醉下股四头肌无主动收缩以及使用止血带则起到相反作用。本研究针对年龄小于40岁的患者，旨在回顾性地将传统“流入”操作过程中测量的髌股轨迹和滑车中心化的关节镜评估结果，与髌骨相关疼痛综合征及其预后进行关联分析。
研究组包括66例男性和49例女性患者（1例双侧）的116个膝关节。关节镜检查时的平均年龄为26岁（范围为12至40岁）。根据关节镜检查前的临床数据，将膝关节分为3个研究组：Gr-T（测试组，无痛髌骨），50个伴有半月板和/或韧带损伤的膝关节；Gr-PRP（与髌骨相关疼痛但无脱位），55个膝关节；Gr-DLC（髌骨脱位），11个膝关节。关节镜技术如下：全身麻醉，高位近端气动止血带（40mmHg），单前外侧入路，通过简单重力作用进行血清流入（2m）。在进行任何关节镜操作之前，系统地测量使髌骨穹窿在视觉上完美中心化进入滑车沟所需的最小屈曲角度。
在“血清流入”关节镜检查情况下，Gr-T组实现完美中心化（FAC）的屈曲角度平均值为39度，Gr-PRP组为52度；这种差异具有高度显著性（p <.0001）。在55个PRP膝关节中的5个以及11个DLC膝关节中的9个中，尽管最大程度屈曲仍无法实现髌骨中心化。FAC值> 65度与髌骨相关临床症状（疼痛和不稳定；PRP + DLC组）显著相关（卡方检验，p = 0.0001），表明髌骨轨迹不良。在PRP组中，“FAC值> 65度”的敏感性较低（0.34），但特异性较高，阳性预测值分别为0.98和0.95。
髌股轨迹的关节镜检查可以提供关于FAC角度的可测量信息，在精确的技术条件下具有可重复性。其在不明原因前膝痛中的诊断价值与传统影像学提供的信息相比，以及它们各自的有效性 - 风险和成本关系，可能是未来前瞻性研究的目的。
