The Quantitative Detection of Posttraumatic Osteoarthrosis after Fractures of the Tibial Plateau Using MRI-based Chondrovolumetry

Abstract

Despite developing better treatment for fractures of the tibial head, particularly intraarticular ones, late degenerative arthritis still presents a very serious problem. Difficulties in the diagnosis of early secondary degenerative changes derive from the fact that plain radiographs are limited to the detection of late manifestations and indirect signs of osteoarthritis because articular cartilage is not visible radiographically. To examine the extent of secondary arthrosis after intraarticular fracture and surgical treatment of the tibial head, we reviewed 25 patients for an objective quantitative measurement of the hyaline cartilage volume of the injured knee. Using magnetic resonance imaging and computer-assisted three-dimensional reconstruction, these MRI-based chondrovolumetric measurements were compared with the hyaline cartilage volume of the uninjured knee of the same patient. We discovered a highly significant reduction (p < 0.001) of the hyaline cartilage volume at the tibial plateau of the injured side. Additionally, there was not only a significant decrease of the joint cartilage at the tibial plateau but also of the cartilage volume of the patella (p = 0.001) and of the femur (p = 0.007) at the injured knee. None of the reviewed patients showed equal or more cartilage volume at the tibial plateau of the injured knee compared to the uninjured side. Our findings indicate that every intraarticular fracture leads more or less to secondary posttraumatic osteoarthrosis. MRI-based chondrovolumetry provides a promising new method for detecting and monitoring articular cartilage leasions and for evaluating various kinds of chondroprotective treatment, such as osteochondral grafting, drugs, physiotherapy, and correction osteotomy.