Arcus Sportklinik, Rastatter Str. 17-19, 75179, Pforzheim, Germany.
Department of Orthopaedics, Medical University of Innsbruck, Innsbruck, Austria.
Knee Surg Sports Traumatol Arthrosc. 2019 Feb;27(2):604-610. doi: 10.1007/s00167-018-5198-6. Epub 2018 Oct 6.
To develop a dynamic physical examination test that functionally simulates actual patellar instability events and that mimics the range of patellar stabilizer insufficiency in an individual patient.
Seventy-eight consecutive patients (male/female 35/43; mean age 22 ± 7 years) with recurrent lateral patellar instability and 35 controls (male/female 16/19; mean age 31 ± 14 years) were prospectively evaluated using the reversed dynamic patellar apprehension test (ReDPAT). Anatomical predisposition was assessed according to Dejour's classification of trochlear dysplasia, tibial tuberosity-trochlear groove distance, tibial tuberosity-posterior cruciate ligament distance, patellar height, and varus/valgus malalignment.
The study group had an average of 3.4 ± 1.0 (1-6) anatomical risk factors for lateral patellar dislocation. Severe trochlear dysplasia (84%) and patella alta (49%) were the most common. Test sensitivity and specificity was 93.7% (95% CI 0.8584-0.9791) and 88.2% (95% CI 0.7255-0.9670), respectively. The positive predictive value reached 94.9% (95% CI 0.8739-0.9859) and the negative predictive value was 85.7% (95% CI 0.6974-0.9519). The ReDPAT results became positive at a mean knee flexion angle of 58° ± 17° (20°-90°). Knee flexion angle correlated significantly with the severity of trochlear dysplasia (p = 0.018), valgus deformity (p = 0.011), and the total number of anatomical risk factors (p = 0.02).
This study introduced the reversed dynamic patellar apprehension test as a reliable clinical examination tool in the assessment of lateral patellar instability. The results of this study indicate that the degree of knee joint flexion at which the provocative sense of apprehension becomes positive correlates with severity of trochlear dysplasia, valgus deformity and the total number of anatomical risk factors for patellar instability. This test indicates the patient-specific end of stable patellar tracking and the beginning of patellar stabilizer insufficiency. Therefore, this test might be helpful in deciding for or against a bony procedure in the treatment of patellar dislocation.
II.
开发一种动态体格检查测试，该测试可模拟实际髌股不稳定事件，并模拟个体患者髌股稳定器不足的范围。
前瞻性评估 78 例复发性外侧髌股不稳定患者（男/女 35/43；平均年龄 22±7 岁）和 35 名对照组（男/女 16/19；平均年龄 31±14 岁），采用反向动态髌股恐惧试验（ReDPAT）。根据 Dejour 的滑车发育不良分类、滑车沟-胫骨结节距离、胫骨结节-后十字韧带距离、髌股高度以及内/外翻对线评估解剖学倾向。
研究组平均有 3.4±1.0（1-6）个外侧髌股脱位的解剖学危险因素。严重的滑车发育不良（84%）和高位髌骨（49%）最为常见。测试的灵敏度和特异性分别为 93.7%（95%CI 0.8584-0.9791）和 88.2%（95%CI 0.7255-0.9670）。阳性预测值达到 94.9%（95%CI 0.8739-0.9859），阴性预测值为 85.7%（95%CI 0.6974-0.9519）。ReDPAT 在平均膝关节屈曲 58°±17°（20°-90°）时结果呈阳性。膝关节屈曲角度与滑车发育不良严重程度（p=0.018）、外翻畸形（p=0.011）和解剖学危险因素总数（p=0.02）显著相关。
本研究引入了反向动态髌股恐惧试验作为外侧髌股不稳定评估的可靠临床检查工具。本研究结果表明，引发恐惧感的膝关节屈曲程度与滑车发育不良、外翻畸形以及髌股不稳定的解剖学危险因素总数相关。该测试提示了髌股轨迹稳定结束和髌股稳定器不足开始的患者特异性角度。因此，该测试可能有助于决定是否对髌股脱位进行骨手术治疗。
II 级。
