Preoperative Sizing of Meniscal Allografts in Meniscus Transplantation

Abstract

The purpose of this study was to determine the accuracy of radiographic and magnetic resonance imaging techniques in preoperative sizing for allograft meniscus transplantation. Twelve cadaveric knee specimens underwent sequential radiographs, magnetic resonance imaging scans, and arthrotomy. Meniscus dimensions were measured in multiple planes for the purpose of determining accuracy of imaging studies in comparison with actual meniscus dimensions. Overall, magnetic resonance imaging proved only slightly more accurate than conventional radiography. The mean difference between magnetic resonance imaging measurements and actual meniscus dimensions was 2.25 +/- 2.04 mm. The mean difference between radiographic measurements and actual meniscus dimensions was 2.35 +/- 1.79 mm. Neither imaging technique was accurate for measuring individual meniscus dimensions, with only 35% of images measuring within 2 mm of actual meniscus dimensions. Using less stringent criteria for accuracy (within 5 mm), radiography and magnetic resonance imaging were 79% and 83% reliable, respectively. Failure to obtain true anteroposterior or lateral images (15 degrees of external and internal rotation) increased measurement inaccuracy. Intraobserver agreement was significantly higher for magnetic resonance imaging than for radiography. Further research into the development of alternative techniques for more reliable meniscus sizing and better understanding of the tolerance for meniscus size mismatch is necessary.

Postoperative change in medial meniscal length in concurrent all-inside meniscus repair with anterior cruciate ligament reconstruction

“…Medial tibial plateau length (MTPL) was measured from the maximum AP dimension of the medial plateau in a radiographic lateral view [14,15]. Anteroposterior radiography was used to measure medial tibial plateau width (MTPW) by obtaining the distance from the medial margin of the tibial plateau to the peak of the medial intercondylar eminence [14,15].…”

“…Anteroposterior radiography was used to measure medial tibial plateau width (MTPW) by obtaining the distance from the medial margin of the tibial plateau to the peak of the medial intercondylar eminence [14,15]. Imaging evaluation was performed using an Achieva 1.…”

Meniscal Allograft Transplantation: Where are we Standing?

“…The most common sizing method is the use of preoperative anterior-posterior and lateral plain radiographs [6,55], although MRI [56,57] and CT scans [58] have also been employed. Plain radiographs take into account bony landmarks, and the most commonly used method has been described by Pollard et al [55].…”

“…Some studies have found that a reduction of 5% of the meniscal size determined by the Pollard method reduces the percentage of meniscal extrusion with no adverse effect on clinical and radiographic outcomes [43]. Despite plain radiograph are more commonly used for graft sizing [6], some studies have demonstrated that the use of MRI is more accurate than plain radiographs [56,57]. An oversized and undersized graft increases forces across the articular cartilage and allograft, respectively [59].…”

Modeling of the condyle elements within a biomechanical knee model

“…Using this ability, four contact points representing the anterior and posterior horns of the lateral and medial menisci are defined on the tibia segment (Fig. 7) [52]. A simple constraint preventing lateral displacement of the tibia with respect to the femur is also defined.…”