Patellar Tendon–Bearing
Also written as: PTB — Patellar Tendon–Bearing
A design feature of a prosthetic socket or orthosis in which weight is borne principally through the patellar tendon, relieving load from the distal limb.
Full Definition
Patellar tendon–bearing (PTB) refers to a load-distribution strategy in which the device's inner trim or brim is shaped to concentrate compressive force over the patellar tendon and tibial flares, unloading the distal tibia, ankle, or foot. Although most commonly associated with PTB prosthetic sockets for below-knee amputees, the term also appears in orthotic contexts when an AFO or similar device incorporates a PTB proximal trim to offload distal pathology such as Charcot foot or diabetic ulcers. Editors must note that 'patellar tendon–bearing' uses an en dash before 'bearing' in many house styles. The abbreviation PTB may be used after first use.
Usage
Usage note: Use an en dash in 'patellar tendon–bearing' (not a hyphen) in formal clinical documents. Confirm context: PTB is more commonly a prosthetic term but appears in advanced orthotic literature.
In Context
- "The prescription called for a patellar tendon–bearing AFO to reduce plantar pressure in a patient with a non-healing calcaneal ulcer." — Orthotics prescription form
- "The editor queried whether the author intended 'patellar tendon-bearing' (hyphen) or 'patellar tendon–bearing' (en dash), as house style required the en dash." — Journal article manuscript editing