The plantaris muscle in most cadavers is a tendinous string with a small muscle belly proximally. Its resemblance to a nerve has caused such frequent confusion in the dissecting laboratory that the plantaris has been called the “freshman's nerve.” There is a syndrome involving rupture of the vestigial muscle after sudden effort, which causes sharp and intense pain in the upper calf, together with local hemorrhaging.
To use this tendon for mitral repair seems unnecessary, since synthetics such as polyester fabrics (e.g., Dacron) heal well and are durable. For the mitral annulus, many collars or rings are commercially available. I use a small piece of knitted, tubular, vascular graft as an annular ring.
As the authors point out, the plantaris tendon is absent in 9% of patients, and needless surgical exploration should be avoided. Use of the plantaris tendon for tendon replacement in hand surgery may be the only logical or practical use.