technetium-tc-99m-medronate and Osteochondritis-Dissecans

Dynamic bone imaging differs from routine multiphase bone scintigraphy by the use of time-activity curves (TACs) and quantitation of data. TACs were divided into an arterial plus blood pool phase (first 60 s at 1 frame/s) and a subsequent early bone uptake phase (24 min at 1 frame/min). Ratios of normalized integrals, from analogous regions were calculated to determine whether blood flow was abnormal. A key feature of the technique is the monitoring of the flow proximally and distally to the area of involvement. This was of importance in distinguishing between two diseases producing the same degree of local hyperemia. Dynamic bone imaging was applied to the differential diagnosis of arthritis, septic arthritis, cellulitis, osteomyelitis, tumor, avascular necrosis, Charcot joint, Legg-Perthes (LP) disease, and Osteochondritis Dissecans (OCD). Although the method is straightforward, there are technical and clinical factors that may affect interpretation of data. Asymmetries in flow may arise due to injection technique, interfering activity of bladder and/or bowel, vascular abnormalities, AV malformation, and venous backflow. The dynamic study is also sensitive to the effects of various modes of therapy. Consideration must be given to these technical and clinical factors for the avoidance of pitfalls in interpretation of the dynamic study.

Topics: Arthritis; Arthritis, Infectious; Arthropathy, Neurogenic; Bone and Bones; Bone Diseases; Bone Neoplasms; Cellulitis; Diagnosis, Differential; Humans; Legg-Calve-Perthes Disease; Osteochondritis Dissecans; Osteomyelitis; Osteonecrosis; Radionuclide Imaging; Technetium Tc 99m Medronate

Topics: Adolescent; Humans; Magnetic Resonance Imaging; Male; Osteochondritis Dissecans; Patella; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Medronate

We report a retrospective study of eighteen patients with pain in the knee or ankle, eleven of whom had osteochondritis dissecans. In these patients the bone-flow time-activity curves were observed after an intravenous injection of a bolus of 99mTc MDP. The curves varied according to the severity of the clinical signs and symptoms. The diagnosis rate was 29% with static scintigraphy and this improved to 57% when dynamic flow studies were used. A positive pattern in the dynamic study together with radiographs and static scintigraphs raised the diagnosis rate to 100%; the sensitivity was 90%. These preliminary results show that dynamic bone scintigraphy holds promise as a technique for identification and management of this condition.

Topics: Adolescent; Adult; Aged; Female; Humans; Knee; Male; Middle Aged; Osteochondritis; Osteochondritis Dissecans; Radioisotope Dilution Technique; Radionuclide Imaging; Regional Blood Flow; Retrospective Studies; Sensitivity and Specificity; Technetium Tc 99m Medronate

A retrospective review of static images and computerized blood flow studies (CBFS) in patients with osteochondritis dissecans (OCD) suggests that CBFS maybe useful in following the clinical course of this disease.

Topics: Adolescent; Adult; Humans; Knee; Osteochondritis; Osteochondritis Dissecans; Radionuclide Imaging; Regional Blood Flow; Technetium Tc 99m Medronate