Coupling of skeletal muscle to a prosthesis for circulatory support.
A durable bond between the end of skeletal muscles and prosthetic structures could, with appropriate linkage, allow circulatory support power by synchronous and/or sequential contraction of several in situ conditioned muscles. Potential advantages relative to a myoplasty wrap involve 1) less traumatic dissection, 2) efficient linear force development, 3) selectable contraction rate, 4) greater stroke work, 5) independent control of muscle pre-load and end diastolic pressure, and 6) independent control of duration of muscle tension and ejection time. However, no existing means of tissue-prosthetic bonding appears adequate. Practicality would demand that full tension bearing capacity by the bond take no longer than muscle conditioning. A prosthesis was developed to achieve those goals. As scaled for this study, it is made of 7,200-7,800 unspun, unplaited, 22 to 26 microns diameter polyester fibers swaged into four taper needles for weaving through distal muscle. The other end is formed into a polyurethane sheathed kernmantel cord for distal fixation. Devices were implanted in six 3 to 4 kg rabbits (unilateral posterior tibial tendon replacement, random side selection with contralateral dissection/closure controls), and their tensile strength was tested at 30 days. All healed well; leg movements were normal after 1 week. Limbs were frozen at -70 degrees C between death and testing. Control failure occurred at 243 +/- 94 N and experimental at 163 +/- 44 N (p = 0.065, t-test); highest estimated requirement was 17.2 N. Interface strength was adequate by 30 days. Continued investigations, addressing other questions, are warranted.
Melvin
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DB
Department of Surgery, University of Cincinnati, Ohio 45267-0558, USA.
Glos
D L
DL
Abiog
M C
MC
Litsky
A S
AS
D000125:Achilles Tendon; D000818:Animals; D001672:Biocompatible Materials; D001696:Biomechanical Phenomena; D001698:Biomedical Engineering; D005069:Evaluation Studies as Topic; D006353:Heart-Assist Devices; D066298:In Vitro Techniques; D008422:Materials Testing; D009119:Muscle Contraction; D011091:Polyesters; D011474:Prosthesis Design; D011817:Rabbits; D019739:Skeletal Muscle Ventricle
D001672:Biocompatible Materials; D011091:Polyesters