Titanium implant impairment and surrounding muscle cell death following neuro‐myoelectrostimulation: An in vivo study

Abstract

Electrical currents have deleterious effects on biomedical metallic implants. However, following arthroplasty, neuro-myoelectrostimulation (NMES) is often used in patient rehabilitation. Such a rehabilitation technique could compromise patient recovery through deleterious effects on metallic alloys and biological tissues. The purpose of our study was to assess the effects of NMES on a Ti6Al4V implant placed in a rat tibial crest and the surrounding muscle tissues. This in vivo study allowed to bring to the fore the prosthesis behavior under mechanical and electromagnetic loads induced by NEMS stimulation. After 3 weeks, implant-to-bone adhesion significantly decreased in stimulated animals compared with nonstimulated animals. Surface mapping indicated titanium implant degradation after NMES. Furthermore, NMES alone did not induce muscle damage contrary to that found in implanted animals. The muscle damage rate was significantly higher in implanted and stimulated animals compared with implanted-only animals. It seems obvious that rehabilitation programs using the NMES technique could induce early deterioration of biomaterial employed for surgical implants. Clinicians should reconsider the use of NMES as a rehabilitation technique for patients with titanium prostheses.

Biocompatibility of four common orthopedic biomaterials following neuroelectromyostimulation: Anin‐vivostudy

“…Contrary to Ti‐Es group, the pull‐out test revealed no significant adhesion strength reduction when NMES was applied for PEEK, Al 2 O 3 and CrCo. In a previous study, we have already demonstrated that an electrical stimulation applied to the muscles surrounding a titanium implant drastically decreased the implant‐to‐bone adhesion . A possible explanation of this result may be found in the properties of Ti6Al4V implant which can be compared with an electrode propagating electrical current to the surrounding tissues .…”

“…Thus, a metal implant in the vicinity of the electrical stimulation area could act as an electrode facilitating the spread of the electric current in the biological tissues. In a previous study, we showed a higher cell death rate on two muscles located in the vicinity of a Ti6Al4V implant fixed on rat tibial crest after two weeks of NMES program . The implant‐to‐bone adhesion was also decreased with the application of electrical stimulation, probably due to wear debris NMES‐induced .…”

“…To reduce animal stress during NMES sessions, rats were slightly anesthetized with a binary intramuscular mixture of 0.65 mL of ketamine (Ketamine 100 Virbac France®, Virbac, Carros, France) and 0.25 mL of chlorpromazine (Largactil®, 0.1 mL per 100 g, Aventis Laboratory, Paris, France) injected in the right intact hindlimb. Animals were placed in supine position and immobilized by slightly tensed straps located on thorax and abdomen . Ankle was firmly held with an angle of 90° to avoid any movements.…”

“…In a previous study, we showed a higher cell death rate on two muscles located in the vicinity of a Ti6Al4V implant fixed on rat tibial crest after two weeks of NMES program. 37 The implant-to-bone adhesion was also decreased with the application of electrical stimulation, probably due to wear debris NMES-induced. 37 Thus, an adverse interaction is likely to occur between metallic alloys and surrounding cells when NMES is used, questioning the relevance of such postarthroplasty rehabilitation technique in which electric current is generated.…”

“…37 The implant-to-bone adhesion was also decreased with the application of electrical stimulation, probably due to wear debris NMES-induced. 37 Thus, an adverse interaction is likely to occur between metallic alloys and surrounding cells when NMES is used, questioning the relevance of such postarthroplasty rehabilitation technique in which electric current is generated. However, the extent to which this reaction occurs with other common biomaterials is still unexplored.…”