Osteoid osteoma is very rarely located in the patella, and can represent a significant diagnostic challenge, resulting in a delay of treatment. Patients with osteoid osteoma of the patella often present with knee pain that is also a typical symptom of trauma or of other diseases such as arthritis, which are much more common than osteoid osteoma. We present two young male patients diagnosed with osteoid osteoma of the patella. Each of these patients had a history of intense knee pain; however, accurate diagnosis of osteoid osteoma in the patella had been delayed for more than one year. Computed tomography (CT) scans or magnetic resonance imaging (MRI) showed a circumscribed lesion of the patella in both patients, whereas X-ray examination (posteroanterior projection) was not able to detect the tumor. Different surgical procedures were performed in these patients for resection of the tumors, and the pathology findings confirmed the diagnosis of osteoid osteoma. Both patients recovered completely from surgery.
Adolescent ; Adult ; Humans ; Male ; Osteoma, Osteoid ; diagnosis ; diagnostic imaging ; surgery ; Patella ; diagnostic imaging ; pathology ; surgery ; Radiography

Adolescent ; Bone Plates ; Fracture Fixation, Internal ; instrumentation ; Fractures, Bone ; diagnostic imaging ; pathology ; physiopathology ; surgery ; Humans ; Male ; Patella ; injuries ; surgery ; Radiography

Patellar metastases are very rare. There have been approximately 20 cases reported in the literature. We have also noted two other reports of patellar metastasis from lung carcinoma as the first manifestation of lung cancer in our literature review. We present a case of patellar metastasis as the first manifestation of lung epidermoid carcinoma in a patient who was a smoker for 33 years.
Arthrography ; Bone Neoplasms/secondary* ; Bone Neoplasms/radiography ; Bone Neoplasms/pathology ; Carcinoma, Squamous Cell/secondary* ; Carcinoma, Squamous Cell/radiography ; Carcinoma, Squamous Cell/pathology ; Case Report ; Human ; Lung Neoplasms/radiography* ; Male ; Middle Age ; Patella* ; Radiography, Thoracic ; Tomography, X-Ray Computed

It has been reported that the common sites of brown tumors are the jaw, pelvis, ribs, femurs and clavicles. We report our experience in a case of brown tumor of the patella caused by primary hyperparathyroidism. An initial radiograph and CT showed an osteolytic lesion and MR images showed a mixed solid and multiloculated cystic tumor in the right patella. One month after the parathyroidectomy, rapid bone formation was observed on both radiographs and CT images.
Adult ; Bone Density ; Bone Neoplasms/*etiology/radiography/*surgery ; Female ; Humans ; Hyperparathyroidism, Primary/*complications/*surgery ; Parathyroidectomy ; Patella/*pathology/radiography ; Tomography, X-Ray Computed