L6690 — Upper extremity addition, frame type socket, interscapular-thoracic
L6690 is a HCPCS Level II code for upper extremity addition, frame type socket, interscapular-thoracic. It belongs to the Orthotic and Prosthetic Procedures and Devices section. Whether Medicare pays it depends on the coverage rule below.
Medicare coverage: Carrier judgment
Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.
From the coverage field of the CMS Alpha-Numeric HCPCS File, release 2026Q3-Jul. This states Medicare’s position on the code, not on your particular claim.
Medically Unlikely Edits — units per day
The most units of L6690 Medicare will pay on one date of service. Bill more on a single line and it is denied. The limit is not the same in every setting, so the row that matters is the one matching the claim you are building.
- practitioner
- 0 — never payable MAI 3 — Date of Service Edit: Clinical · CMS Policy
- outpatient
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
- DME supplier
- 2 units MAI 2 — Date of Service Edit: Policy · Anatomic Consideration
The adjudication indicator decides whether exceeding the limit is worth appealing at all: MAI 1 is a line edit you can support with documentation, MAI 3 is a date-of-service edit that is also appealable, and MAI 2 is absolute — no documentation overrides it. CMS MUE 2026Q3.
The CMS record for L6690
- Long descriptor
- Upper extremity addition, frame type socket, interscapular-thoracic
- Short descriptor
- Frame typ sock interscap-tho
- Added
- January 1, 1988
- BETOS
- D1F
- Pricing indicator
- 38 — DMEPOS
The official wording. This is what the code means.
CMS's 28-character form, which is what shows up on a remittance advice.
When CMS introduced the code.
Berenson-Eggers Type of Service — CMS's own analytic grouping.
Orthotics, prosthetics, prosthetic devices and vision services. Price subject to floors and ceilings.
Codes adjacent to L6690
HCPCS has no hierarchy — related items simply sit next to each other in the numbering. If L6690 is not quite right, the correct code is very often within a few positions of it.
- L6677Upper extremity addition, harness, triple control, simultaneous operation of terminal device and elbow
- L6680Upper extremity addition, test socket, wrist disarticulation or below elbow
- L6682Upper extremity addition, test socket, elbow disarticulation or above elbow
- L6684Upper extremity addition, test socket, shoulder disarticulation or interscapular thoracic
- L6686Upper extremity addition, suction socket
- L6687Upper extremity addition, frame type socket, below elbow or wrist disarticulation
- L6688Upper extremity addition, frame type socket, above elbow or elbow disarticulation
- L6689Upper extremity addition, frame type socket, shoulder disarticulation
- L6691Upper extremity addition, removable insert, each
- L6692Upper extremity addition, silicone gel insert or equal, with or without locking mechanism, each
- L6693Upper extremity addition, locking elbow, forearm counterbalance
- L6694Addition to upper extremity prosthesis, below elbow/above elbow, custom fabricated from existing mold or prefabricated, socket insert, silicone gel, elastomeric or equal, for use with locking mechanism
- L6695Addition to upper extremity prosthesis, below elbow/above elbow, custom fabricated from existing mold or prefabricated, socket insert, silicone gel, elastomeric or equal, not for use with locking mechanism
- L6696Addition to upper extremity prosthesis, below elbow/above elbow, custom fabricated socket insert for congenital or atypical traumatic amputee, silicone gel, elastomeric or equal, for use with or without locking mechanism, initial only (for other than initial, use code l6694 or l6695)
- L6697Addition to upper extremity prosthesis, below elbow/above elbow, custom fabricated socket insert for other than congenital or atypical traumatic amputee, silicone gel, elastomeric or equal, for use with or without locking mechanism, initial only (for other than initial, use code l6694 or l6695)
- L6698Addition to upper extremity prosthesis, lock mechanism, excludes socket insert
Questions about L6690
What is HCPCS code L6690?
L6690 is a HCPCS Level II code for upper extremity addition, frame type socket, interscapular-thoracic. It sits in the Orthotic and Prosthetic Procedures and Devices section.
Does Medicare cover L6690?
The CMS HCPCS file marks L6690 as "Carrier judgment". Coverage is decided by your Medicare contractor, not by national policy. Whether this is paid depends on the LCD for your jurisdiction and on what the documentation supports.