Glossary · Anatomy

Supraspinatus tendon

The supraspinatus tendon is the distal fibrous attachment of the supraspinatus muscle, spanning from the supraspinous fossa of the scapula to the superior facet of the greater tubercle of the humerus. It is the most frequently torn component of the rotator cuff and anchors the muscle's role in initiating shoulder abduction.

Verified May 8, 2026 · 9 sources ↓

Drawn from NIHEnICD10DataIcdcodesFindacode

Definition

Source · Editorial summary grounded in 9 cited references ↓

The supraspinatus tendon transmits force from the supraspinatus muscle—which occupies the supraspinous fossa of the scapula—to the superior facet of the greater tubercle of the humerus. As the tendon courses laterally, it passes beneath the acromion and coracoacromial arch, a region of inherent mechanical vulnerability. The tendon blends with the glenohumeral joint capsule, making it structurally integral to shoulder stability as well as motion.

Internally, the tendon is not uniform. Its anterior portion carries roughly 2.9 times the tensile stress of the posterior portion and displays a double-layered interwoven fiber architecture, whereas the posterior division has thinner, more dispersed fibers. This biomechanical asymmetry explains why full-thickness tears almost always originate at the anterior leading edge of the tendon, near the critical zone of relative avascularity approximately 1 cm proximal to the insertion.

Clinically, supraspinatus tendon pathology spans a spectrum—tendinopathy (often documented as tendinosis or tendinitis on MRI), partial-thickness tear, and full-thickness tear with or without retraction. Each point on that spectrum maps to a different ICD-10-CM code family and, in surgical cases, may affect how CPT 29827 or open repair codes are supported in documentation. Imaging characterization (partial vs. full thickness, degree of retraction, fatty infiltration of the muscle belly) drives both surgical planning and coding specificity.

Why it matters

Imprecise documentation of supraspinatus tendon pathology is one of the leading causes of rotator cuff claim denials and post-payment audits. The ICD-10-CM code M75.1x (rotator cuff tear, non-traumatic) requires laterality and tear completeness to reach a billable child code—M75.121 for a complete right-sided tear, for example. Submitting the non-specific parent code M75.1 triggers automatic payer edits because it is flagged as non-billable. Separately, traumatic tears must route to the S46.0x series, and mixing traumatic and non-traumatic codes for the same episode creates an NCCI conflict. On the surgical side, CPT 29827 covers arthroscopic rotator cuff repair regardless of how many tendons are repaired in a single session, so billing 29827 twice when both the supraspinatus and subscapularis are repaired through separate portals is an unbundling error that will generate an overpayment finding on audit.

Common mistakes

Where people most often go wrong with this concept.

Source · Editorial brief grounded in cited references ↓

Submitting parent code M75.1 instead of a billable child code (e.g., M75.121 for complete right-sided tear)—M75.1 is non-billable and will deny.
Coding a traumatic supraspinatus tear under M75.1x (non-traumatic) rather than the S46.0x series, creating a clinical-coding mismatch auditors flag.
Billing CPT 29827 twice when the supraspinatus and another rotator cuff tendon are repaired in the same operative session—the code covers all tendons repaired arthroscopically in one encounter.
Using M75.5 (shoulder bursitis) or M75.8 (other shoulder lesion) when imaging confirms a tendon tear rather than pure bursitis—specificity to the confirmed pathology is required.
Defaulting to M65.81 (synovitis/tenosynovitis) for supraspinatus tendinosis when the M75.x category is the index-directed, payer-preferred code family for rotator cuff lesions.
Omitting retraction measurement and tear thickness from operative or MRI documentation, which prevents coders from selecting the most specific ICD-10 subcode and undermines medical necessity for surgical repair.

Related codes

Codes commonly involved when this concept appears in practice.

CPT

Modifiers

RT Right side LT Left side 59 Distinct procedural service XS Separate structure

Frequently asked questions

Source · Generated from the editorial pipeline, verified against 9 cited references ↓

01What is the difference between supraspinatus tendinosis and a supraspinatus tear for coding purposes?

Tendinosis (or tendinitis) without imaging confirmation of a tear maps to M75.8 (other shoulder lesion) or M75.5 (bursitis) depending on clinical context—not to the M75.1x tear codes. Applying a tear code without documented imaging or intraoperative confirmation of an actual tear is a coding pitfall that creates audit exposure.

02Is CPT 29827 reported once or twice when the surgeon repairs both the supraspinatus and subscapularis tendons arthroscopically?

Once. CPT 29827 covers arthroscopic rotator cuff repair for the entire rotator cuff in a single operative session regardless of how many individual tendons are addressed. Billing the code twice for the same patient on the same date through separate portals is an unbundling error.

03When does a supraspinatus tear get coded to S46.0x instead of M75.1x?

When the tear results from an acute traumatic event—a fall, direct blow, or sudden forceful movement—the S46.0x series applies, and the coder must add the appropriate 7th character for encounter type. M75.1x is reserved for degenerative or non-traumatic tears. Assigning M75.1x to a trauma patient can trigger a clinical-coding mismatch denial.

04Why is M75.1 flagged as non-billable?

M75.1 is a parent/header code. Payers require the laterality and completeness data captured in its child codes (e.g., M75.101 for unspecified complete tear, right; M75.121 for complete tear, right). Submitting the three-character parent code will produce an automatic denial because it lacks the specificity required for reimbursement.

05What clinical tests are used to assess supraspinatus tendon integrity?

The Empty Can Test (Jobe Test) and Full Can Test are the most widely used orthopedic provocative tests. The arm is positioned at 90 degrees of abduction in the scapular plane with full internal rotation (Empty Can) or external rotation (Full Can), and downward resistance is applied. Pain or weakness constitutes a positive result suggesting supraspinatus impingement or tear.

Sources & references

Editorial content was developed using the following public sources. Last verified May 8, 2026.

Mira AI Scribe

When Mira captures supraspinatus tendon pathology, it prompts for four data points that determine code selection and defend medical necessity: (1) laterality—right, left, or bilateral; (2) tear classification—tendinopathy/tendinosis (no tear), partial-thickness, or full-thickness; (3) mechanism—atraumatic/degenerative versus acute traumatic event (routes to M75.1x vs. S46.0x series respectively); and (4) retraction distance in millimeters as documented on MRI or intraoperatively. For surgical encounters, Mira flags CPT 29827 as a single-unit code regardless of the number of rotator cuff tendons repaired arthroscopically in the session, and suppresses duplicate billing if a second tendon repair is captured in the same note. When documentation describes only imaging signal change without a discrete tear, Mira defaults to M75.8 (other shoulder lesion) rather than a tear code and inserts a query to the clinician to confirm or deny tear presence before claim submission. On traumatic encounters, Mira applies the S46.0x code with the appropriate 7th character for encounter type (A = initial, D = subsequent, S = sequela) and alerts the coder if the injury date conflicts with a non-traumatic code already on the account.

See Mira's approach

Related terms

Rotator cuff Anatomy

The rotator cuff is a group of four muscles and their tendons—supraspinatus, infraspinatus, teres minor, and subscapularis—that stabilize the glenohumeral joint and power shoulder rotation and elevation.