Appearance of previously injured posterior cruciate ligaments on magnetic resonance imaging.

Background. The appearance of normal and injured cruciate ligaments on magnetic resonance imaging (MRI) has been well described in the literature. Few studies have reported on changes found on sequential imaging of injured posterior cruciate ligaments (PCLs) during the healing process, however. Methods. Ten consecutive patients with isolated injuries to the PCL were evaluated with an initial clinical examination, x-rays, and MRI of the injured knee. Clinical examination and imaging studies were repeated at a minimum of 6 months after the initial injury. These studies were interpreted by radiologists blinded to the study design. Results. Seven of the 10 patients were found to have PCL continuity on repeat MRI. One patient continued to demonstrate an abnormal appearance of the PCL on MRI, and 2 patients were lost to follow-up. Conclusions. Despite the healed appearance of their PCLs on imaging studies, 6 of 7 patients continued to demonstrate laxity on clinical examination. All returned to their preinjury occupations and to recreational sports, however. Our results are consistent with previously reported data.