Roentgenographic Analysis of Patellofemoral Congruence

Ligament Reconstruction versus Distal Realignment for Patellar Dislocation

“…Posteroanterior, lateral, and patellofemoral axial radiographs were taken preoperatively and at followup ( Table 2). Axial Merchant [35] views with the knee at 45°fl exion were used to analyze the medial and lateral facets of the patellofemoral joint. The radiographic parameters measured on the axial radiographs included the sulcus angle [7], lateral patellofemoral angle, and lateral patellar displacement as described by Laurin et al [30].…”

Quantitative analysis of dynamic patellar tracking in patients with lateral patellar instability using a simple video system

“…Patella height was assessed on lateral radiographs by measuring Insall-Salvati ratio [23] and Caton-Deschamps index [24]. On the Merchant's view, sulcus angle and congruence angle were measured for detecting trochlear dysplasia and abnormal congruence [25]. For assessing lateral displacement of tibial tuberosity and lateral patellar inclination, tibial tuberosity-trochlear groove distance (TT-TG) [2,4] and patellar tilt [26] were measured on axial CT images.…”

Case Report: Quantitative MRI of Tibial Tubercle Transfer During Active Quadriceps Contraction

“…3C); (4) patellar tilt angle as described by Sasaki and Yagi (PTA-S) [16]: this angle is defined as the angle between the line that passes through the widest part of the patella and a line tangential to the anterior femoral condyles (Fig. 3D); (5) sulcus angle as described by Merchant et al [12]: the angle between the sulcus and the medial and lateral condyles (Fig. 3E); (6) congruence angle as described by Merchant et al [12]: the angle created by the bisect of the sulcus angle and a line from the deepest point of the sulcus to the most posterior aspect of the patella (Fig.…”

“…3D); (5) sulcus angle as described by Merchant et al [12]: the angle between the sulcus and the medial and lateral condyles (Fig. 3E); (6) congruence angle as described by Merchant et al [12]: the angle created by the bisect of the sulcus angle and a line from the deepest point of the sulcus to the most posterior aspect of the patella (Fig. 3F); and (7) TT-TG as described by Lustig et al [10]: the horizontal distance between the tibial tubercle and trochlear groove (Fig.…”

“…The tibial tubercle was transferred 22 mm medially intraoperatively, reducing TT-TG to a value below the surgical threshold of 20 mm (Table 2) [10]. Because a trochleoplasty was not performed in this case, adequate medial transfer was essential to correct the patellofemoral relationship in the setting of a relatively shallow trochlear groove compared with a normal mean value of 142°described previously (Table 2) [4,12]. The MPFL was reconstructed after the medial tibial tubercle transfer to create a check reign to prevent apprehension.…”