title: Thermal effects of 2450 MHz microwave exposure near a titanium alloy plate implanted in rabbit limbs.
abstract: This study aimed to examine the safety profile of microwave therapy on limbs with metal implants. New Zealand white rabbits were implanted with titanium alloy internal fixation plates. Femurs were exposed to 20, 40, 60, or 80 W of microwave radiation for 30 min (microwave applicator at 2450 MHz), and temperatures of the implants and muscles adjacent to implants were recorded. To evaluate thermal damage, nerves were electrodiagnostically assessed immediately after radiation, and histologic studies performed on nerve and muscle sections. As expected, implant temperature was highest in the exposure field. Temperatures of limbs with titanium alloy implants increased significantly at 60 and 80 W, with a significant decline in the nerve conduction velocity and acute thermal injuries in nerves and muscles adjacent to implants. However, temperature remained unchanged and no adverse effects were observed in nerves and muscles at 20 and 40 W. These findings are inconsistent with the current notion that surgical metal implants in the treatment field are contraindications for microwave therapy. Hence, we believe that a lower dose of continuous wave microwave irradiation is safe for limbs with titanium alloy implants.
authors.affiliation: Department of Rehabilitation, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai, China.
authors.forename: Dongmei
authors.initials: D
authors.lastname: Ye
authors.forename: Yiming
authors.initials: Y
authors.lastname: Xu
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.forename: Xianxuan
authors.initials: X
authors.lastname: Feng
authors.forename: Tengfei
authors.initials: T
authors.lastname: Fu
authors.forename: Han
authors.initials: H
authors.lastname: Zhang
authors.forename: Lan
authors.initials: L
authors.lastname: Jiang
authors.forename: Yuehong
authors.initials: Y
authors.lastname: Bai
mesh_terms: D000497:Alloys; D000818:Animals; D004307:Dose-Response Relationship, Radiation; D055724:Electrophysiological Phenomena / Q000528:radiation effects; D005121:Extremities / Q000528:radiation effects*; D005269:Femur / Q000528:radiation effects; D051379:Mice; D008872:Microwaves / Q000009:adverse effects*; D009132:Muscles / Q000166:cytology / Q000528:radiation effects; D019736:Prostheses and Implants; D011817:Rabbits; D012584:Sciatic Nerve / Q000502:physiology / Q000528:radiation effects; D013696:Temperature; D014025:Titanium
chemical_list: D000497:Alloys; D014025:Titanium
keywords: burn injury; microwave; muscle; sciatic nerve; temperature; titanium alloy