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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Bone Cements, Female, Follow-Up Studies, Hip Prosthesis, Humans, Male, Middle Aged, Prospective Studies, Prosthesis Failure, Technetium Tc 99m Medronate, Time Factors.
user
Does sequential Tc-99m MDP bone scan after cementless total hip arthroplasty in asymptomatic patients? Context: To evaluate the distribution and degree of radioactivity on sequential Tc-99m methylene diphosphonate (Tc-99m MDP) scans in the diagnosis of postoperative loosening in asymptomatic patients who underwent cementless total hip replacement. Tc-99m MDP scans were obtained every three months where possible, for one year in those patients who underwent total hip replacement using a Harris Galante cementless prosthesis. Eighty-three scans from 45 patients were obtained. Uptake was assessed within the five periprosthetic zones (zone 1: greater trochanter; 2: lateral stem of the prosthesis; 3: tip of the prosthesis; 4: medial stem of the prosthesis; and 5: lesser trochanter) using an arbitrary 5-point grading system. Grade 1 indicated normal uptake and Grade 5 indicated highest uptake. The grade of uptake within each zone was then analyzed against their postoperative ages. The radioactivity regressed to Grade 1 or 2 from Grade 4 or 5 within 12 months after cementless total hip replacement in 87.5% and 93.8% of patients in zones 2 and 4, respectively. Even though the radioactivity within zones 1, 3, and 5 tended to decrease, persistent elevation of activity (over grade 2) lasted up to 12 months after surgery in 31% or 37% of the patients.
assistant
The radioactivity after cementless total hip replacement tended to regress in proportion to the postimplant age. The regression rate varied depending on the periprosthetic zones. Final Decision: yes