Other enthesopathies (M77) ICD-10-CM
The M77 code range covers other enthesopathies with 27 ICD-10-CM diagnosis codes. 20 of them are billable and valid for claim submission in fiscal year 2026, and the category headers group them but cannot themselves be billed.
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
- bursitis NOS M71.9
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
Codes in the M77 Range 27 codes · 20 billable
- M77 Other enthesopathiesNon-billable
- M77.0 Medial epicondylitisNon-billable
- M77.00 Medial epicondylitis, unspecified elbow
- M77.01 Medial epicondylitis, right elbow
- M77.02 Medial epicondylitis, left elbow
- M77.1 Lateral epicondylitisNon-billable
- M77.10 Lateral epicondylitis, unspecified elbow
- M77.11 Lateral epicondylitis, right elbow
- M77.12 Lateral epicondylitis, left elbow
- M77.2 Periarthritis of wristNon-billable
- M77.20 Periarthritis, unspecified wrist
- M77.21 Periarthritis, right wrist
- M77.22 Periarthritis, left wrist
- M77.3 Calcaneal spurNon-billable
- M77.30 Calcaneal spur, unspecified foot
- M77.31 Calcaneal spur, right foot
- M77.32 Calcaneal spur, left foot
- M77.4 MetatarsalgiaNon-billable
- M77.40 Metatarsalgia, unspecified foot
- M77.41 Metatarsalgia, right foot
- M77.42 Metatarsalgia, left foot
- M77.5 Other enthesopathy of foot and ankleNon-billable
- M77.50 Other enthesopathy of unspecified foot and ankle
- M77.51 Other enthesopathy of right foot and ankle
- M77.52 Other enthesopathy of left foot and ankle
- M77.8 Other enthesopathies, not elsewhere classified
- M77.9 Enthesopathy, unspecified
Clinical Terms in This Code Range
Definitions from the National Library of Medicine for conditions coded in the M77 range.
Elbow Tendinopathy
Inflammation (tendinitis) or degeneration (tendinosis) of the tendons of the elbow.
Enthesopathy
A disorder occurring at the site of insertion of TENDONS or LIGAMENTS into bones or JOINT CAPSULES.
Metatarsal Bones
The five long bones of the METATARSUS, articulating with the TARSAL BONES proximally and the PHALANGES OF TOES distally.
Metatarsalgia
Pain in the region of the METATARSUS. It can include pain in the METATARSAL BONES; METATARSOPHALANGEAL JOINT; and/or intermetatarsal joints (TARSAL JOINTS).
Morton Neuroma
A nerve inflammation in the foot caused by chronic compression of the plantar nerve between the METATARSAL BONES.
Periarthritis
Inflammation of the tissues around a joint. (Dorland, 27th ed)
About the M77 Code Range
The ICD-10 code section M77 covers various types of enthesopathies, which are disorders involving the attachment of tendons or ligaments to bone. These codes include specific conditions such as medial and lateral epicondylitis (commonly known as "tennis elbow" or "golfer's elbow"), periarthritis of the wrist, calcaneal spur (heel spur), metatarsalgia, and other enthesopathies affecting the foot, ankle, and upper limbs.
The detailed codes under M77 help specify the exact location and side for enthesopathy diagnoses. For example, M77.0 series relates to medial epicondylitis, often referred to simply as "epicondylitis," with subcodes identifying right (M77.01) or left elbow involvement (M77.02). Similarly, lateral epicondylitis is captured under M77.1, with distinctions for right and left elbows. Periarthritis codes (M77.2) focus on wrist inflammation, while calcaneal spur codes (M77.3) address heel bone spurs, a common cause of foot pain. Additionally, codes for metatarsalgia (M77.4) document pain in the ball of the foot. The broader category also includes less common enthesopathies of foot and ankle, or other regions like the shoulder and hand (M77.8 and M77.9), assisting medical coders in accurately classifying tendon-related disorders based on location and side. Using these codes ensures precise identification of conditions like "epicondylitis," "postcalcaneal bursitis," or "tendinitis," facilitating appropriate clinical documentation and treatment planning.
Questions About This Page
How many billable codes are in the M77 range?
Of the 27 codes in this range, 20 are billable and valid for claim submission from October 1, 2025 through September 30, 2026. Category header codes group them but cannot be reported on claims.
What does the M77 range classify?
The range classifies other enthesopathies. Each code links to its own reference page with billing status, MS-DRG grouping, coding notes, and clinical information.
Related References
Source: CMS FY 2026 ICD-10-CM Tabular List and order file, effective October 1, 2025 through September 30, 2026.
