R321 – Phalanx, metacarpal
OHIP Radiology Code — MUSCULOSKELETAL SYSTEM SURGICAL PROCEDURES · Schedule of Benefits
R321 is a surgical procedure listed under the Musculoskeletal System Surgical Procedures section. It is eligible for payment to the surgeon (suffix A), surgical assistant (suffix B), and anaesthetist (suffix C). The surgeon's fee is a set amount. The fees for the surgical assistant and anaesthetist are calculated based on a unit system combining base units and time units, as detailed in the General Preamble (- for assistants, - for anaesthetists). Payment for a second assistant requires authorization by a medical consultant as it is not on the pre-approved list ().
When to Use
- Use R321 for open reduction or internal fixation of phalanx or metacarpal fractures when the procedure is performed as a distinct surgical intervention.
- Use R321 when performing surgical debridement or corrective osteotomy on the phalanx or metacarpal bones, provided it meets the definition of a surgical procedure rather than a minor office procedure.
Common Pitfalls
- Billing R321 alongside minor procedure codes for the same site; ensure the procedure is not considered inclusive of a minor surgical service already performed.
- Failing to document the specific fracture or pathology site, which can lead to rejections if the claim does not match the diagnostic code or surgical report.
- Attempting to bill a second surgical assistant without prior medical consultant authorization, which is strictly required for this code as it is not on the pre-approved list.
Billing Tips
- Ensure the surgical report clearly justifies the complexity of the procedure to support the base fee and any applicable age-based or trauma premiums.
- When billing for surgical assistants or anaesthetists, verify that the base units and time units are calculated according to the General Preamble (GP85-GP86 and GP92-GP93) to avoid payment adjustments.
Effective: April 1, 2026
N. Musculoskeletal System Surgical Procedures
MUSCULOSKELETAL SYSTEM SURGICAL PROCEDURES
Surgical
Cardiovascular Surgical Procedures
The fee for a surgical assistant (suffix B) is calculated based on basic units plus time units. The number of basic units is listed in the 'Asst' column of the Schedule. Time units accrue for each 15-minute interval of service. For detailed calculation rules, see pages - of the General Preamble.
The fee for an anaesthetist (suffix C) is calculated based on basic units plus time units. The number of basic units is listed in the 'Anae' column of the Schedule. Time units accrue for each 15-minute interval of service. For detailed calculation rules and applicable extra units, see pages - of the General Preamble.
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