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The Philadelphia cervical collar, usually shortened to “Philly collar”, is a two-piece foam neck collar that gives gross immobilization of the mid-cervical spine. It is sized on two measurements, neck height and neck circumference, and it must be fitted by a healthcare professional. This page describes products and general use; it is not medical advice.
Who uses it: clinic and hospital staff who stock or apply cervical orthoses, buyers comparing collar types, and students learning the vocabulary. Sizing and warnings below follow the manufacturer’s instructions for use (IFU) for the Össur Philadelphia collars, checked 2026-10-30.
What is a Philadelphia (Philly) cervical collar?
It is a cervical orthosis made of a front piece and a back piece that overlap and fasten with hook-and-loop straps. The IFU states its intended use as “to provide gross immobilization to the cervical spine”. “Philly”, “Philadelphia” and “Philly-type” are all used for this design; in the FDA’s AccessGUDID device database, a record described as a “Philly type trac cervical collar” sits under the generic FDA product code IQK, “Orthosis, Cervical”. openFDA lists that code as a Class 1 device under 21 CFR 890.3490.
The collar is X-ray and CT lucent, according to the IFU. For the semi-rigid Aspen design see the Aspen cervical collar guide; for soft foam collars see the soft cervical collar guide; for how all collar types compare, see cervical collar types and sizing. Other support devices are covered in back brace types and what a knee immobilizer is.
How the Philly collar is built
- Two pieces: a front piece with a chin recess and a back piece, packaged as a set.
- Material: the Össur adjustable model is made of non-toxic Plastazote foam and is latex-free (adjustable-model IFU).
- Fastening: hook-and-loop straps on both sides.
- Edges: the IFU says the Plastazote can be trimmed or heat moulded, with edges rounded smooth.
Fixed-size and adjustable Philadelphia collars
| Variant | How size is set | Key difference |
|---|---|---|
| Philadelphia Tracheotomy Collar (original, fixed sizes) | Chosen from infant, pediatric and adult sizes by neck height and circumference | Supplied in set sizes |
| Adjustable Philadelphia Tracheotomy Collar | Height set by sliding the lower front piece and locking two tabs; circumference set by tearing away foam sections of the back piece | About 1 inch (25 mm) of neck-height adjustability; it conforms to sizes 2, 3 and 4 of the original; lock-once design (product sheet and IFU) |
Philadelphia collar sizing: the two measurements
The IFU says proper sizing is critical to achieve comfort and proper immobilization. Height is the vertical distance from the top of the shoulder to the tip of the chin (Measurement A). Circumference is measured around the neck (Measurement B). Many retail listings reduce this to small, medium and large; the manufacturer’s table is more detailed.
Neck height (Measurement A)
| Size group | Neck height |
|---|---|
| Infant | 1.25 in (3.2 cm) |
| Pediatric | 1.75 in (4.4 cm) |
| Adult | 2.25 in (5.7 cm), 3.25 in (8.3 cm), 4.25 in (10.8 cm) or 5.25 in (13.3 cm) |
Neck circumference (Measurement B)
| Size | Neck circumference |
|---|---|
| Infant | 6-8 in (15.2-20.3 cm) |
| Pediatric | 8-11 in (20.3-27.9 cm) |
| Adult Small | 10-13 in (25.4-33.0 cm) |
| Adult Medium | 13-16 in (33.0-40.6 cm) |
| Adult Large | 16-19 in (40.6-48.3 cm) |
| Adult Extra Large | 19 in+ (48.3 cm+) |
Adjustable model sizing guide
| Example (IFU guide) | Height setting | Size | Foam sections torn off |
|---|---|---|---|
| Stout | 2 | Large | None |
| Average male | 3 | Medium | 1 each side |
| Thin female | 4 | Small | 2 each side |
The IFU adds that actual sizing must be verified by the healthcare provider for each patient individually.
How to choose: what the manufacturer says
- Measurements: both neck height and neck circumference are needed; a circumference alone does not set the size.
- Fixed or adjustable: the fixed-size model comes in set infant, pediatric and adult sizes; the adjustable model covers sizes 2, 3 and 4 of the original with a single lock-once height setting.
- Clinical suitability: indications, contraindications and cautions are set out in the manufacturer’s instructions for use and are decided by a healthcare professional, not by a product page.
- Prescription status: the adjustable model is labelled as sold by or on the order of a physician under US federal law.
Handling and care basics
- Fitting: the collar must be fitted and adjusted by a healthcare professional, and the IFU does not supersede hospital protocol or a clinician’s direct orders.
- Warnings: the IFU carries clinical warnings and contraindications; read the full document before use in a clinical setting.
- Cleaning the product: wipe with a damp cloth and mild soap and air dry. Do not machine-wash, tumble dry, iron, bleach or use fabric softener. Avoid perfumes and harsh cleaning agents; rinse after salt or chlorinated water.
- Reuse: the original collar IFU describes it as “single patient – multiple use”.
Common mistakes
- Resizing an adjustable collar. The adjustable model is designed to be sized and locked into a single position only once; it is not intended to be resized.
- Measuring only circumference. The IFU requires both height and circumference.
- Skipping size verification. The IFU says actual sizing must be verified by the healthcare provider for each patient individually.
- Harsh cleaners or machine washing, both excluded by the care instructions.
FAQ
Is a Philly collar the same as a Philadelphia cervical collar?
Yes. “Philly” is the common short form of “Philadelphia”, and “Philly-type” is used as a generic term for this two-piece foam design. In FDA’s AccessGUDID these products fall under the generic product code IQK, “Orthosis, Cervical”.
How is a Philadelphia collar sized?
By two measurements: the vertical distance from the top of the shoulder to the tip of the chin, and the neck circumference. The manufacturer’s tables are shown above, and a healthcare provider verifies the fit.
What is a Philly collar made of?
The adjustable Össur model is made of non-toxic Plastazote foam, is latex-free and uses hook-and-loop straps, according to its IFU.
Is the adjustable Philadelphia collar prescription-only?
Its labelling states that US federal law restricts the device to sale by, or on the order of, a physician.
How does it differ from an Aspen collar?
The Philadelphia collar is a two-piece foam collar with straps. For the Aspen design, see the Aspen cervical collar guide.
Sources
All sources checked 2026-10-30.
- Össur, Philadelphia Tracheotomy Collar Instructions for Use (1378-001-13): https://media.ossur.com/ossur-dam/image/upload/pi-documents-global/PHILADELPHIA_TRACHEOTOMY_COLLAR_1378_001_13.pdf
- Össur, Adjustable Philadelphia Tracheotomy Collar product sheet PN60056: https://media.ossur.com/ossur-dam/image/upload/product-documents-global/Philadelphia_Adjustable_Tracheotomy_Collar_us_en_PN60056.pdf
- Adjustable Philadelphia collar IFU (English, p. 7): https://cdn.ortoped.ca/Assets/PDFs/ossur_philadelphiaajustable_instructions.pdf
- NLM AccessGUDID device record: https://accessgudid.nlm.nih.gov/devices/00614138126985
- openFDA device classification, product code IQK: https://api.fda.gov/device/classification.json?search=product_code:IQK
