Written and maintained by CASRAI Editorial Board
Last updated
General product and regulatory information only; this is not medical advice.
Short answer
A plinth is a flat, padded board with legs intended for medical purposes, on which a patient is placed for treatment or examination. That is the wording of the FDA regulation at 21 CFR 890.3520, which classifies it as a Class I device. In clinics it is commonly called a treatment table or treatment plinth.
Definition and scope
The FDA’s definition (21 CFR 890.3520(a)) is short: “A plinth is a flat, padded board with legs that is intended for medical purposes. A patient is placed on the device for treatment or examination.” The definition names no height range, no powered adjustment and no particular clinical discipline, so it covers any padded, legged treatment surface that fits that description.
The same regulation sets the classification: Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807, subject to the limitations in 21 CFR 890.9, and exempt from the quality management system requirements of part 820 except those concerning records and complaint files.
How a plinth is used in practice
The regulation describes the use in two words: treatment or examination. The patient is placed on the device; the plinth itself delivers no therapy. Manufacturer product pages show how the basic idea is built out. One UK manufacturer page for a “treatment plinth”, for example, lists adjustable sections, electric height adjustment and a stated safe working load of up to 320 kg (Medi-Plinth). Those figures describe that one product, not plinths in general; any load rating or adjustment range must come from the manufacturer’s own documentation for the model in question.
Plinth vs multi-function physical therapy table
FDA regulates two differently named tables in its physical medicine device regulations. The distinction is whether the table itself supplies therapy.
| Device | Regulation | What the regulation says it is | FDA class |
|---|---|---|---|
| Plinth | 21 CFR 890.3520 | A flat, padded board with legs; the patient is placed on it for treatment or examination | Class I (general controls); exempt from premarket notification (subject to 890.9) |
| Multi-function physical therapy table | 21 CFR 890.5880 | A motorized table equipped to provide patients with heat, traction and muscle relaxation therapy | Class II (performance standards) |
In other words, a table that only supports the patient fits the plinth definition, while a motorized table equipped to provide heat, traction and muscle relaxation therapy fits the multi-function table definition and sits in a higher class.
Where it matters for labs, clinics and supply decisions
- Regulatory class. A plain plinth is Class I and exempt from premarket notification; a multi-function physical therapy table is Class II. The class follows the device’s described function in the regulation.
- Naming on documents. Catalogues and quotes may say plinth, treatment table or physical therapy table. When a product description mentions heat, traction or motorized therapy, compare it against 21 CFR 890.5880 rather than relying on the name.
- Specifications. Load rating, height range and adjustable sections are set by the manufacturer for each model and are not part of the FDA definition, so they are read from the manufacturer’s product documentation.
For related clinic equipment, see medical supplies for a doctor’s office, what therapeutic ultrasound is and its FDA class and what a gait trainer is.
Common misunderstandings
“Plinth” can mean something else
In architecture a plinth is the base of a column or statue. That is unrelated to the medical device defined in 21 CFR 890.3520.
A treatment table is not automatically a “physical therapy table”
The regulation’s “multi-function physical therapy table” is specifically motorized and equipped for heat, traction and muscle relaxation therapy. A padded table without that equipment matches the plinth definition instead.
Class I does not mean unregulated
Class I devices remain subject to general controls. The plinth regulation exempts the device from premarket notification and most of part 820, but keeps requirements concerning records and complaint files.
FAQ
What is a plinth?
A flat, padded board with legs intended for medical purposes, on which a patient is placed for treatment or examination (21 CFR 890.3520).
Is a plinth the same as a treatment table?
In everyday clinical use the terms commonly refer to the same kind of padded treatment surface. The FDA regulation uses the name “plinth”.
Is a plinth the same as a physical therapy table?
Not in the regulations. A plinth is Class I; a multi-function physical therapy table, a motorized table providing heat, traction and muscle relaxation therapy, is Class II under 21 CFR 890.5880.
What FDA class is a plinth?
Class I (general controls), exempt from premarket notification subject to the limitations in 21 CFR 890.9.
Sources
- 21 CFR 890.3520, Plinth (eCFR). Checked 30 October 2026.
- 21 CFR 890.5880, Multi-function physical therapy table (eCFR). Checked 30 October 2026.
- Medi-Plinth, Physio BO plinth mat table product page (one manufacturer’s product, as illustration only). Checked 30 October 2026.
