HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

HCPCS Level II code L5321 describes an above-knee prosthetic component consisting of a molded socket with an open end, a SACH foot, an endoskeletal system, and a single-axis knee; the service is provision of a transfemoral prosthesis (prosthetic fabrication and fitting) typically delivered in an outpatient prosthetics/orthotics clinic or specialty orthotics facility where prosthetic fabrication, alignment, and patient training occur.

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HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

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Clinical & Coding Specifications

Clinical Context

A 68-year-old male patient with a transfemoral (above-knee) amputation presents to a specialty prosthetics clinic for fabrication and fitting of a definitive above-knee prosthesis. The patient has a well-healed residual limb with stable volume, intact skin, and demonstrated ability to bear weight on the socket during pre-prosthetic training. The prosthetic prescription calls for an above-knee, molded socket with an open end, endoskeletal system, a SACH (solid ankle cushioned heel) foot, and a single-axis knee joint, corresponding to the HCPCS Level II code L5321.

The clinical workflow includes: initial evaluation by a prosthetist with review of medical history and surgical notes; measurement and casting or digital scanning of the residual limb; fabrication of a custom molded socket and endoskeletal pylon and components; bench alignment and assembly of the SACH foot and single-axis knee; fitting appointment with static and dynamic alignment checks; gait training with a physical therapist; and follow-up adjustments for socket comfort and function. Typical documentation includes the prosthetic order, limb measurements or scan, component manufacturer and model, alignment notes, patient's functional level, goals, and justification for component selection.

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`97760`	Orthotic(s) management and training, initial encounter; fitting and training with use of prosthetic device(s), lower extremity, initial encounter	Used for training and education when the patient is first fitted with the above-knee prosthesis
`97530`	Therapeutic activities, direct (one-on-one) patient contact by the provider; each 15 minutes	Used by physical or occupational therapists for functional mobility and gait training sessions post-fitting
`73660`	Radiologic examination, ankle; complete, minimum of 3 views (example musculoskeletal imaging)	Ordered when evaluating residual limb or contralateral limb bony alignment issues before prosthetic fitting if clinically indicated
`99213`	Office or other outpatient visit for the evaluation and management of an established patient, typically 15 minutes	Used for routine follow-up visits to assess socket fit, skin integrity, and function
`97535`	Self-care/home management training (eg, activities of daily living and compensatory training), direct one-on-one contact	Used when training the patient in transfers, donning/doffing, and activities of daily living with the new prosthesis

Related Modifiers

5 rows

Modifier	Description	When to Use
22	Modifier –22 (Increased Procedural Services) is used when a reported procedure is substantially more extensive than normally required. The CPT Manual and CMS state it may be appended only when the…	- When to use: Append modifier -22 to a procedural CPT code when the service performed is substantially more extensive than the usual service described by that code — i.e., the procedure required…
23	Modifier -23 (Unusual Anesthesia) is used on anesthesia service CPT codes when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia…	- Use modifier -23 only on anesthesia CPT codes (00100–01999) when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia because of…
59	Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)…	- Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a…
P6	Modifier P6 indicates a declared brain‑dead patient whose organs are being removed for donor purposes. It is part of the Anesthesia Physical Status Modifiers (P1–P6) and corresponds to ASA VI. The…	- When to use: Append CPT modifier P6 to anesthesia codes in the 00100–01999 range when the anesthesia provider documents a declared brain‑dead patient whose organs are being removed for donor…
3P	The CPT Category II modifier -3P denotes a performance‑measure exclusion when a required quality action was not performed because of system‑level constraints. It is appended only to Category II…	- When to apply: Use CPT Category II modifier 3P only with Category II (‘‘F’’) codes when a specific quality measure’s specifications allow a system‑level exclusion — append 3P to indicate the…

Related Provider Taxonomies

8 rows

Taxonomy Code	Specialty	Notes
2080P0208X	Pediatric Infectious Diseases Physician	A pediatrician trained to care for children in the diagnosis, treatment and prevention of infectious diseases. This specialist can apply specific know…
208800000X	Urology Physician	A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has compreh…
3336C0002X	Clinic Pharmacy	A pharmacy in a clinic, emergency room or hospital (outpatient) that dispenses medications to patients for self-administration under the supervision o…
103TP2700X	Deactivated - Psychologist Psychotherapy
174V00000X	Clinical Ethicist	A clinical ethicist has been trained in bioethics and ethics case consultation. The clinical ethicist addresses medical-ethical dilemmas arising in c…
251C00000X	Developmentally Disabled Services Day Training Agency	These agencies are authorized to provide day habilitation services to developmentally disabled individuals who live in their homes. The function of d…
2081P2900X	Pain Medicine (Physical Medicine & Rehabilitation) Physician	A physician who provides a high level of care, either as a primary physician or consultant, for patients experiencing problems with acute, chronic or …
207UN0902X	Nuclear Imaging & Therapy Physician	A nuclear medicine physician who specializes in nuclear imaging and therapy.

Related ICD-10-CM Codes

27 rows

ICD-10-CM Code	Description
E10.621	Type 1 diabetes mellitus with foot ulcer
E11.621	Type 2 diabetes mellitus with foot ulcer
G54.2	Cervical root disorders, not elsewhere classified
G56.41	Causalgia of right upper limb
G82.20	Paraplegia, unspecified
G82.21	Paraplegia, complete
M16.11	Unilateral primary osteoarthritis, right hip
M16.12	Unilateral primary osteoarthritis, left hip
M17.11	Unilateral primary osteoarthritis, right knee
M17.12	Unilateral primary osteoarthritis, left knee

Showing 1–10 of 27

HCPCS Level II L5000: Partial Foot Shoe Insert with Longitudinal Arch, Toe Filler

HCPCS-L5010-PARTIAL-FOOT-MOLDED-SOCKET-ANKLE-HEIGHT-TOE-FILLER

HCPCS L5010: Partial Foot Molded Socket, Ankle Height, With Toe Filler

HCPCS-L5020-PARTIAL-FOOT-MOLDED-SOCKET-TIBIAL-TUBERCLE-TOE-FILLER

HCPCS L5020: Partial Foot Molded Socket with Toe Filler

HCPCS-L5050-ANKLE-SYMES-MOLDED-SOCKET-SACH-FOOT

HCPCS L5050: Ankle/Symes Molded Socket with SACH Foot

HCPCS-L5060-ANKLE-SYMES-METAL-FRAME-MOLDED-LEATHER-SOCKET-ARTICULATED-ANKLE-FOOT

HCPCS L5060: Ankle/Symes Metal Frame with Molded Leather Socket

HCPCS-L5100-BELOW-KNEE-MOLDED-SOCKET-SHIN-SACH-FOOT

HCPCS Level II L5100: Below-Knee Molded Socket with Shin and SACH Foot

HCPCS-L5105-BELOW-KNEE-PLASTIC-SOCKET-SACH-FOOT

HCPCS L5105: Below-Knee Plastic Socket Prosthesis with SACH Foot

HCPCS-L5150-KNEE-DISARTICULATION-MOLDED-SOCKET-EXTERNAL-KNEE-SACH-FOOT

HCPCS L5150: Knee Disarticulation Molded Socket with External Knee and SACH Foot

HCPCS-L5160-KNEE-DISARTICULATION-MOLDED-SOCKET-BENT-KNEE-SACH-FOOT

HCPCS Level II L5160: Knee Disarticulation Molded Socket, Bent Knee Configuration

HCPCS-L5200-ABOVE-KNEE-MOLDED-SOCKET-SINGLE-AXIS-KNEE-SACH-FOOT

HCPCS Level II L5200: Above-knee Prosthesis with Molded Socket and Single-axis Knee

Showing 1–10 of 472

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

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Clinical & Coding Specifications

Clinical Context

Related CPT Codes

CPT Code	Description	Relationship to This Procedure
`97760`	Orthotic(s) management and training, initial encounter; fitting and training with use of prosthetic device(s), lower extremity, initial encounter	Used for training and education when the patient is first fitted with the above-knee prosthesis
`97530`	Therapeutic activities, direct (one-on-one) patient contact by the provider; each 15 minutes	Used by physical or occupational therapists for functional mobility and gait training sessions post-fitting
`73660`	Radiologic examination, ankle; complete, minimum of 3 views (example musculoskeletal imaging)	Ordered when evaluating residual limb or contralateral limb bony alignment issues before prosthetic fitting if clinically indicated
`99213`	Office or other outpatient visit for the evaluation and management of an established patient, typically 15 minutes	Used for routine follow-up visits to assess socket fit, skin integrity, and function
`97535`	Self-care/home management training (eg, activities of daily living and compensatory training), direct one-on-one contact	Used when training the patient in transfers, donning/doffing, and activities of daily living with the new prosthesis

Related Modifiers

5 rows

Modifier	Description	When to Use
22	Modifier –22 (Increased Procedural Services) is used when a reported procedure is substantially more extensive than normally required. The CPT Manual and CMS state it may be appended only when the…	- When to use: Append modifier -22 to a procedural CPT code when the service performed is substantially more extensive than the usual service described by that code — i.e., the procedure required…
23	Modifier -23 (Unusual Anesthesia) is used on anesthesia service CPT codes when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia…	- Use modifier -23 only on anesthesia CPT codes (00100–01999) when a procedure that normally requires no anesthesia or only local anesthesia must be performed under general anesthesia because of…
59	Modifier 59 indicates a distinct procedural service when two procedures that are not normally billed together are clinically and procedurally separate. The CPT definition (as reiterated by CMS)…	- Use modifier -59 to report a distinct procedural service when documentation supports that the procedure reported is not normally billed together with another service on the same day because of a…
P6	Modifier P6 indicates a declared brain‑dead patient whose organs are being removed for donor purposes. It is part of the Anesthesia Physical Status Modifiers (P1–P6) and corresponds to ASA VI. The…	- When to use: Append CPT modifier P6 to anesthesia codes in the 00100–01999 range when the anesthesia provider documents a declared brain‑dead patient whose organs are being removed for donor…
3P	The CPT Category II modifier -3P denotes a performance‑measure exclusion when a required quality action was not performed because of system‑level constraints. It is appended only to Category II…	- When to apply: Use CPT Category II modifier 3P only with Category II (‘‘F’’) codes when a specific quality measure’s specifications allow a system‑level exclusion — append 3P to indicate the…

Related Provider Taxonomies

8 rows

Taxonomy Code	Specialty	Notes
2080P0208X	Pediatric Infectious Diseases Physician	A pediatrician trained to care for children in the diagnosis, treatment and prevention of infectious diseases. This specialist can apply specific know…
208800000X	Urology Physician	A urologist manages benign and malignant medical and surgical disorders of the genitourinary system and the adrenal gland. This specialist has compreh…
3336C0002X	Clinic Pharmacy	A pharmacy in a clinic, emergency room or hospital (outpatient) that dispenses medications to patients for self-administration under the supervision o…
103TP2700X	Deactivated - Psychologist Psychotherapy
174V00000X	Clinical Ethicist	A clinical ethicist has been trained in bioethics and ethics case consultation. The clinical ethicist addresses medical-ethical dilemmas arising in c…
251C00000X	Developmentally Disabled Services Day Training Agency	These agencies are authorized to provide day habilitation services to developmentally disabled individuals who live in their homes. The function of d…
2081P2900X	Pain Medicine (Physical Medicine & Rehabilitation) Physician	A physician who provides a high level of care, either as a primary physician or consultant, for patients experiencing problems with acute, chronic or …
207UN0902X	Nuclear Imaging & Therapy Physician	A nuclear medicine physician who specializes in nuclear imaging and therapy.

Related ICD-10-CM Codes

27 rows

ICD-10-CM Code	Description
E10.621	Type 1 diabetes mellitus with foot ulcer
E11.621	Type 2 diabetes mellitus with foot ulcer
G54.2	Cervical root disorders, not elsewhere classified
G56.41	Causalgia of right upper limb
G82.20	Paraplegia, unspecified
G82.21	Paraplegia, complete
M16.11	Unilateral primary osteoarthritis, right hip
M16.12	Unilateral primary osteoarthritis, left hip
M17.11	Unilateral primary osteoarthritis, right knee
M17.12	Unilateral primary osteoarthritis, left knee

Showing 1–10 of 27

HCPCS Level II L5000: Partial Foot Shoe Insert with Longitudinal Arch, Toe Filler

HCPCS-L5010-PARTIAL-FOOT-MOLDED-SOCKET-ANKLE-HEIGHT-TOE-FILLER

HCPCS L5010: Partial Foot Molded Socket, Ankle Height, With Toe Filler

HCPCS-L5020-PARTIAL-FOOT-MOLDED-SOCKET-TIBIAL-TUBERCLE-TOE-FILLER

HCPCS L5020: Partial Foot Molded Socket with Toe Filler

HCPCS-L5050-ANKLE-SYMES-MOLDED-SOCKET-SACH-FOOT

HCPCS L5050: Ankle/Symes Molded Socket with SACH Foot

HCPCS-L5060-ANKLE-SYMES-METAL-FRAME-MOLDED-LEATHER-SOCKET-ARTICULATED-ANKLE-FOOT

HCPCS L5060: Ankle/Symes Metal Frame with Molded Leather Socket

HCPCS-L5100-BELOW-KNEE-MOLDED-SOCKET-SHIN-SACH-FOOT

HCPCS Level II L5100: Below-Knee Molded Socket with Shin and SACH Foot

HCPCS-L5105-BELOW-KNEE-PLASTIC-SOCKET-SACH-FOOT

HCPCS L5105: Below-Knee Plastic Socket Prosthesis with SACH Foot

HCPCS-L5150-KNEE-DISARTICULATION-MOLDED-SOCKET-EXTERNAL-KNEE-SACH-FOOT

HCPCS L5150: Knee Disarticulation Molded Socket with External Knee and SACH Foot

HCPCS-L5160-KNEE-DISARTICULATION-MOLDED-SOCKET-BENT-KNEE-SACH-FOOT

HCPCS Level II L5160: Knee Disarticulation Molded Socket, Bent Knee Configuration

HCPCS-L5200-ABOVE-KNEE-MOLDED-SOCKET-SINGLE-AXIS-KNEE-SACH-FOOT

HCPCS Level II L5200: Above-knee Prosthesis with Molded Socket and Single-axis Knee

Showing 1–10 of 472

Frequently Asked Questions

References

1.CPT® Codes and Descriptions. AAPC. Retrieved Aug 11, 2026.Maintains the CPT code set's official descriptions and guidelines, licensed from the American Medical Association, used as the definitional source for CPT codes on this page.
2.HCPCS Quarterly Update. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's quarterly release of HCPCS Level II codes and short/long descriptors, the source for HCPCS code definitions and update history.
3.ICD-10-CM Full Code List. Centers for Medicare & Medicaid Services (CMS). Retrieved Aug 11, 2026.CMS's complete ICD-10-CM diagnosis code list, used to cross-reference diagnosis codes associated with this procedure or service.

Published by

Trek Health powers OpenPayer with a leading commercial payer intelligence platform, seamlessly converting fragmented payer data into actionable insights for provider organizations.

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HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

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HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

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Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Codes

References

Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Codes

References

HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

Sign up for hcpcs L5321 policy alerts

HCPCS L5321: Above-Knee Molded Socket Prosthesis with SACH Foot

Sign up for hcpcs L5321 policy alerts

Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Codes

What does HCPCS code L5321 represent?

Which billing modifiers are commonly used with L5321?

What clinical documentation supports billing for L5321?

Which CPT codes commonly accompany the provision and follow-up of an L5321 prosthesis?

Which payers are commonly engaged for coverage of L5321 and how do payer policies factor into billing?

References

Clinical & Coding Specifications

Clinical Context

Related CPT Codes

Related Modifiers

Related Provider Taxonomies

Related ICD-10-CM Codes

Related Codes

What does HCPCS code L5321 represent?

Which billing modifiers are commonly used with L5321?

What clinical documentation supports billing for L5321?

Which CPT codes commonly accompany the provision and follow-up of an L5321 prosthesis?

Which payers are commonly engaged for coverage of L5321 and how do payer policies factor into billing?

References