Periarticular lesions detected on magnetic resonance imaging: prevalence in knees with and without symptoms.

OBJECTIVE: To evaluate, using magnetic resonance imaging (MRI), the prevalence of periarticular lesions in older persons with or without knee pain, and to assess the association of these lesions with knee pain.

METHODS: Subjects ages 45 years and older, with or without knee pain, were recruited from Veterans Affairs medical centers and from the community. Weight-bearing posteroanterior, skyline, and lateral radiographs were obtained in all subjects. Subjects were divided into 3 groups: those with radiographic OA (ROA) and knee pain (n = 376), those with ROA and no knee pain (n = 51), and those with neither ROA nor knee pain (n = 24). A single knee (the more symptomatic one in subjects with knee pain) was imaged with a 1.5T scanner using T1- and T2-weighted and proton-density spin-echo imaging sequences. MRIs were read for the presence of periarticular lesions, which were categorized (according to their general location) as being either peripatellar (prepatellar, superficial infrapatellar, deep infrapatellar) or "other periarticular lesions" (semimembranosus-tibial collateral ligament bursitis, anserine bursitis, iliotibial band syndrome, tibiofibular cyst).

RESULTS: Patients with knee pain had more severe radiographic disease than did subjects who were asymptomatic. Peripatellar lesions (prepatellar or superficial infrapatellar) were present in 12.1% of the patients with knee pain and ROA, in 20.5% of the patients with ROA and no knee pain, and in 0% of subjects with neither ROA nor knee pain (P = 0.116). However, other periarticular lesions were present in 14.9% of patients with both ROA and knee pain, in only 3.9% of patients with ROA but no knee pain, and in 0% of the group with no knee pain and no ROA (P = 0.004).

CONCLUSION: Although peripatellar lesions are equally common among subjects with knee pain and those without knee pain, other periarticular lesions (including bursitis and iliotibial band syndrome) are significantly more common among subjects with knee pain and may contribute to pain in these individuals.