10.3.9 - Trochlear Morphology in Healthy People: Implications for Osteochondral Allograft Transplantation
- M. Mologne (Vail, US)
- M. Mologne (Vail, US)
- M. Provencher (Vail, CO, US)
- A. Peebles (Vail, US)
- T. Mologne (Appleton, US)
Abstract
Purpose
The purpose of this study was: 1) to assess trochlear width, depth, and sulcus angle via magnetic resonance imaging (MRI) in patients without patellofemoral problems and 2) to determine whether bench measurements of donor femurs can better match donors and patients.
Methods and Materials
An analysis was performed on 209 deidentified MRIs. Trochlear width and depth were measured 15 mm and 20 mm distal to the most proximal articular surface. MRI’s were classified into three groups based on trochlear depth (Group 1: 0-4.0 mm; Group 2: 4.1-6.0 mm; 16 Group 3: > 6.0 mm). Difference in trochlear depth at the two distances was calculated. The same protocol was performed on 23 cadaveric knees.
Results
209 MRIs (ages 12-57, average age: 25.8 years) were included in the review. Mean trochlear depths at 15mm and 20mm were significantly different between the groups. Group 3 had significantly larger trochlear widths than Groups 1 and 2. All MRIs showed an increase in trochlear depth between 15 and 20 mm (mean increase: 1.31 ± 0.78 mm). There was no significant difference in trochlear depths between MRI and cadaveric groups. For MRI groups at 15 mm, the resultant apex decreased 10° between Groups 1 and 2 and decreased 7.4° between Groups 2 and 3.
| Group 1 | Group 2 | Group 3 | |
| Trochlear Width | 36.25 mm | 37.50 mm | 39.00 mm |
| Trochlear Depth | 3.35 mm | 5.21 mm | 6.80 mm |
| Apex (Sulcus Angles) | 159 degrees | 149 degrees | 141.6 degrees |
Conclusion
Tibial width has historically been used to assess OCA transplantation but does not consider trochlear depth nor does it guarantee suitable pairings. Assuming trochleae are perfect isosceles triangles, one can measure trochlear width and cartilage sulcus angle via MRI to assess trochlear depth. Additionally, trochlear data was distributed into three independent groups. Consideration of trochlear depth and its distribution may enable more accurate OCA matching.
