Anterior knee pathology is a frequent cause of joint pain and limitation of function and mobility among patients presenting to an orthopaedic department. Proper recognition and treatment of pathologic conditions depend on the knowledge of normal anatomy and of the various abnormalities, which affect this area of the knee and may present with anterior knee pain. A broad array of benign and malignant processes may be manifested as anterior knee discomfort, and this common clinical entity is among the most frequent indications for MR imaging of the lower extremities. Clinical history and physical examination are also of paramount importance. The disorders can be categorized and differentiated primarily according to their location. Traumatic or non-traumatic disorders of the patella, patellar retinacula, quadriceps and patellar tendons and supra or infrapatellar fat pad can be the source of symptoms. This article includes a comprehensive pictorial essay of the characteristic MR features of common and uncommon disorders causing anterior knee pain. For accurate assessment of the aforementioned clinical problem, a radiologist should be able to identify typical MR imaging patterns that contribute in establishing the correct diagnosis and thus tailoring the appropriate therapy. Level of evidence IV.

The authors present an unusual case of atypical iliopsoas bursitis in an 81 years-old female patient. The patient asked for medical advice due to a chronic left hip and lower abdominal pain with no specific characteristics. Physical examination revealed a palpable left-sided pelvic mass. Ultrasound examination demonstrated a purely cystic mass that was presumed to be an ovarian cystic malignancy. The patient was referred for an MRI examination, which showed a cystic lesion extending from the left iliac crest to the anterior aspect of the ipsilateral hip joint (maximum diameter 18 cm), coursing below the iliopsoas tendon indicative of an extremely distended iliopsoas bursa.

Introduction: Sciatica is a common problem, usually caused by disc herniation or spinal stenosis. Low back pain is also present in most cases. When sciatica is the unique clinical finding, especially in young patients, extraspinal pathology should be investigated.