A tendon sheath is a layer of synovial membrane around a

tendon A tendon or sinew is a tough, high-tensile-strength band of dense fibrous connective tissue that connects muscle to bone. It is able to transmit the mechanical forces of muscle contraction to the skeletal system without sacrificing its ability ...

. It permits the tendon to stretch and not adhere to the surrounding fascia. It has two layers: *

synovial sheath A synovial sheath is one of the two membranes of a tendon sheath which covers a tendon. The other membrane is the outer fibrous tendon sheath. The tendon invaginates the synovial sheath from one side so that the tendon is suspended from the membra ...

* fibrous tendon sheath Fibroma of the tendon sheath has been described.

References

Musculoskeletal system {{anatomy-stub