Specialty
Orthopedics billing services
Orthopedics billing services have one job above the others: get the global surgical package right.
See where claims are getting stuck. No patient data needed.
Medicare pays most orthopedic procedures as a package covering the surgery and 10 or 90 days of follow-up, so every visit, cast change and return to the operating room in that window is coded inside or outside the package with the modifier that says which. Around that sit fracture codes that include the first cast, arthroscopy edits that bundle debridement, a per-joint unit rule for injections, and surgeries that need prior authorization. Remitwright gives orthopedic practices a dedicated biller who tracks the global period per patient and works every denial back to its cause.
Orthopedics billing is one of Remitwright's specialty billing services, each set out with its own code families, denial reasons and payer rules.
Last reviewed by the Remitwright billing team. Editorial policy
- 20600-20611
- 22510-22634
- 23000-28899
Denials
Why orthopedic claims get denied
The reasons that come up most on orthopedic remittances, with the usual cause and the fix. Code explanations are our own; the official list is maintained by X12.
| Code | Reason | Usual cause | The fix |
|---|---|---|---|
| CO-97 | Included in another service | A follow-up visit, cast change or suture removal billed inside the 90 day window without a qualifying modifier, or a casting code billed with the fracture code that already includes the first cast | A global calendar per patient from the date of surgery, and a scrubber rule that drops casting codes when a fracture or surgical code for the same area is on the claim |
| CO-4 | Procedure inconsistent with the modifier | Modifier 57 on a 10 day procedure, 25 on the surgery line, or a bilateral procedure billed as two units instead of one line with 50 | Modifier rules keyed to each code's global indicator and bilateral indicator from the fee schedule, checked before release |
| CO-197 | Precertification absent | Joint replacement, spine surgery, arthroscopy or an implant scheduled without the plan's authorization, or performed at a facility the authorization does not name | Authorization worked from the surgical schedule with the CPT codes, side and site, and the number carried to the claim; the hospital's request confirmed for Medicare outpatient cervical fusion and stimulators |
| CO-236 | Procedure combination not allowed (NCCI) | Chondroplasty or loose body removal billed with another knee arthroscopy code, limited debridement billed with a shoulder arthroscopy, or a diagnostic arthroscopy billed with the surgical one | NCCI procedure-to-procedure edits run before submission; G0289 only for a different compartment of the same knee; 59 or XS only when the second procedure is on the other side |
| CO-151 | Units exceed the payer's limit | Two units of 20610 for a knee and its bursa, or several closed fracture codes for bones treated under one cast | Units set per joint and per cast, with the medically unlikely edit value checked at charge entry |
| CO-50 | Not medically necessary | A hyaluronan series started without documented knee osteoarthritis and the plan's period of failed conservative care, or repeated before the plan's interval has passed | The payer's criteria pulled before the first injection is scheduled, with the dates of prior treatment in the note |
| CO-16 | Claim lacks information | A postoperative care claim with modifier 55 that does not match the surgeon's code or date of surgery, or an assistant at surgery line without an operative report that names the assistant | Split-care claims built from the surgeon's claim, and the assistant's role documented in the operative note before billing |
Codes
Common orthopedic codes and modifiers
Code families by number with our own one-line explanations. CPT descriptors belong to the AMA and are not reproduced here.
| Codes | What the family covers |
|---|---|
| 20600-20611 | Aspiration or injection of a joint or bursa by joint size, with or without ultrasound; one unit per joint, however many of its surrounding bursae are also treated |
| 22510-22634 | Spinal fusion, vertebroplasty and vertebral augmentation families, billed as one primary code for the first level and add-on codes for each additional level |
| 23000-28899 | Open and closed procedures by body region from shoulder to foot, most with a 90 day global period that absorbs routine follow-up, cast changes and suture removal |
| 29000-29799 | Casting, splinting and strapping, payable on their own only when no fracture or surgical code for the same area is billed and the practice expects to give only the initial care |
| 29805-29999 | Arthroscopy by joint, where the diagnostic scope, limited debridement and clean-up synovectomy fold into the main procedure under NCCI edits |
| 99202-99215 | Office visits, payable alongside surgery only as the decision visit for a major procedure, an unrelated visit inside the global period, or a separate problem on the day of a minor procedure |
| HCPCS L codes | Knee, ankle and spinal braces fitted in the office, billed with the orthotic codes CMS maintains in HCPCS Level II under each payer's DME rules |
Modifiers that matter
- 57
- The visit at which the decision for a major surgery (90 day global) is made, on the day of or the day before the procedure. Medicare does not pay it on the day of or before a 0 or 10 day procedure.
- 24
- A visit during the postoperative period for a problem unrelated to the surgery, with a note that says why it is unrelated. Care for the surgical diagnosis or its complications stays inside the package.
- 25
- A significant, separately identifiable visit on the day of a minor procedure such as a joint injection or a cast. The decision to do the minor procedure itself never earns a visit, new patient or not.
- 58, 78 and 79
- A staged or planned return to the operating room (58), an unplanned return for a complication (78), or an unrelated procedure in the global period (79). A distinct procedure in the window starts its own postoperative period.
- 54 and 55
- The surgeon hands follow-up to another provider under a written transfer of care. Both bill the same procedure code with the surgery date; 55 is billed only after the receiving provider has seen the patient. Not used with 0 day codes.
- 50, RT and LT
- Bilateral procedures. Medicare practitioners bill one line with modifier 50 and one unit unless the code is bilateral by definition; ambulatory surgical centers bill two lines with RT and LT.
- 80, 82 and AS
- An assistant at surgery, paid only for procedures where Medicare allows one. Physicians use 80, 81 or 82; physician assistants, nurse practitioners and clinical nurse specialists use AS.
Payers
Payer notes
- MedicareMedicare pays surgery as one of three packages. A 0 day package covers endoscopies and some minor procedures with no post-operative days. A 10 day package runs 11 days counting the surgery day. A 90 day package runs 92 days, counting the day before surgery, the day of surgery and the 90 days after. The package includes pre-operative visits after the decision, post-operative visits, pain management, dressing changes and removal of casts, splints, sutures and staples. The decision visit for major surgery (modifier 57), unrelated visits, diagnostic tests, distinct procedures and a return to the operating room for a complication are paid separately.1
- Medicare and commercial plans that apply NCCIFracture and dislocation codes include the first cast, splint or strap, so casting codes are billed on their own only when the cast is the whole treatment and the practice expects to give only the initial care. Surgical arthroscopy includes diagnostic arthroscopy. Knee chondroplasty (29877) and loose body removal (29874) are not billed with other knee arthroscopy codes; G0289 covers a different compartment of the same knee. Shoulder arthroscopy includes limited debridement. Joint aspiration or injection is one unit per joint. Bilateral surgery is billed on one line with modifier 50 and one unit.2
- MedicareMultiple surgeries by the same surgeon on the same day are ranked by fee schedule amount and paid at 100 percent for the highest valued procedure and 50 percent for the second through fifth, with modifier 51 on the additional procedures; a sixth or later procedure is suspended for review and paid by report. Bilateral surgery with modifier 50 is paid at 150 percent of the fee schedule amount. A physician serving as assistant at surgery is paid 16 percent of the surgical fee schedule amount with modifier 80, 81 or 82; a physician assistant, nurse practitioner or clinical nurse specialist billing with AS is paid 85 percent of that physician amount, which works out to 13.6 percent, and only for procedures where Medicare allows an assistant.3
- Medicare (hospital outpatient departments)Cervical fusion with disc removal and implanted spinal neurostimulators performed in a hospital outpatient department have needed prior authorization since July 1, 2021, and facet joint interventions since July 1, 2023. The hospital submits the request. Standard decisions take up to 7 calendar days for requests on or after January 1, 2025, and expedited decisions 2 business days.4
- Medicare (WISeR model states)Knee arthroscopy for knee osteoarthritis is among the services in the WISeR model, which runs from January 1, 2026 through December 31, 2031 in Arizona, New Jersey, Ohio, Oklahoma, Texas and Washington. Requesting prior authorization is voluntary; a claim for a listed service without one goes to medical review before payment.5
- UnitedHealthcare commercialMost hyaluronate brands are excluded from coverage under the plan's drug policy. The covered products need a knee osteoarthritis diagnosis, at least 3 months of conservative therapy or intra-articular steroids without functional improvement, pain that interferes with function, and dosing on the FDA label. Authorization covers one course per joint for 6 months; a repeat course needs a documented response and 6 months since the last one. The policy states prior authorization is not required.6
Authorizations
Medicare has no prior authorization for office orthopedics, but three programs reach the specialty. Hospital outpatient cervical fusion with disc removal, implanted spinal neurostimulators and facet joint interventions need a request the hospital files before the procedure. The WISeR model puts knee arthroscopy for osteoarthritis and nerve stimulator implants under prior authorization or pre-payment review in six states from 2026. Everything else is judged after payment against coverage criteria. Commercial plans generally require authorization for joint replacement, spine surgery, arthroscopy and implants, often through a musculoskeletal management vendor with its own portal and site-of-service rules. Your biller keeps the matrix by payer, CPT code and facility, requests authorization from the surgical schedule with the imaging and conservative care notes the criteria call for, and carries the number and the approved site to the claim.
Documentation traps
- The decision for surgery recorded only in the operative note, so the visit billed with modifier 57 has nothing to stand on
- The operative report silent on the knee compartment or the side, which is what G0289, the arthroscopy edits and the RT and LT rules are checked against
- A post-operative visit note that does not say whether the problem is related to the surgery, so modifier 24 fails on review
- The transfer of care for split billing not written into both providers' records, so the 54 and 55 claims do not match
- Prior conservative care for an injection series without dates, so the plan's waiting period cannot be shown when the first claim is reviewed
- The cast supply left off the chart on the one visit where a cast is the whole treatment, which is the only time the casting and supply codes are payable
What a specialist checks
Specialist or generalist for orthopedics billing?
A generalist biller can enter an orthopedic claim. Whether it pays turns on three things specific to orthopedics billing, and a specialty-aware biller checks each one.
Code families
Each family billed with what the chart has to show for it.
- 20600-20611
- 22510-22634
- 23000-28899
Modifiers
Applied only where the note supports them, line by line.
- 57
- 24
- 25
If you are moving from another billing company or an in-house biller, switching billing companies follows a plan: the old and new processes run side by side until the new one is proven, and every login and every orthopedic claim stays in your name.
What we handle
What we handle for orthopedic practices
- Medical codingCPT, ICD-10 and modifiers assigned correctly
- Prior authorizationAuths requested, tracked, attached to claims
- Claim submissionScrubbed, submitted and tracked to acceptance
- Payment postingERAs and EOBs posted, variances flagged
- Denial managementEvery denial read, worked and appealed
- A/R follow-upUnpaid claims chased before filing limits
A dedicated biller with named cover, working inside your system and reporting to you on one written page. How it works sets out the five stages.
Software
Systems orthopedic practices usually run
Your biller works inside your system as a user you create. All the systems we work in.
Questions
Questions about orthopedics billing
How long is the global period for orthopedic surgery?
It depends on the code. Medicare assigns 0, 10 or 90 post-operative days, shown in the global column of the Physician Fee Schedule Look-Up Tool. A 10 day package is 11 days counting the surgery day. A 90 day package is 92 days: the day before, the day of, and 90 days after. Follow-up visits, cast changes and suture removal inside the window are not billed.
Can we bill a visit on the day of surgery?
For a major procedure, only the visit where the decision for surgery was made, with modifier 57, on the day of or the day before. For a 0 or 10 day procedure, the decision to do it is part of the procedure and is not a visit. A separate, significant problem evaluated the same day can be billed with modifier 25 and documentation to match.
Can we bill the cast with fracture care?
No. Closed, percutaneous and open fracture treatment codes include the first cast, splint or strap. The casting codes and the supply code are billable when the cast is the only treatment and the practice expects to give only the initial care. Removal or repair codes apply only when a different practice applied the cast.
Why was our knee chondroplasty denied with the meniscectomy?
NCCI does not allow 29877 or 29874 with other knee arthroscopy codes. Meniscectomy codes 29880 and 29881 already include chondroplasty in any compartment. The one path is G0289, and only for removal of a loose body or foreign body from a different compartment of the same knee. The operative note has to name the compartment.
How does Medicare pay bilateral and multiple procedures?
Bilateral: one line, modifier 50, one unit, paid at 150 percent of the fee schedule amount, unless the code is already bilateral by definition. Multiple: procedures ranked by fee schedule amount, with the highest paid at 100 percent and the second through fifth at 50 percent, modifier 51 on the lesser ones; a sixth or later procedure is reviewed and paid by report. Commercial plans publish their own rules, and your biller keeps them by payer.
Which orthopedic surgeries need prior authorization from Medicare?
In a hospital outpatient department: cervical fusion with disc removal, implanted spinal neurostimulators and facet joint interventions, requested by the hospital, with standard decisions in 7 calendar days and expedited in 2 business days. In the six WISeR states from 2026: knee arthroscopy for osteoarthritis, among other listed services. Office procedures have no authorization step but are reviewed against coverage criteria.
How do split-care claims work when another provider does the follow-up?
The surgeon bills the procedure with modifier 54 and the follow-up provider bills the same code with modifier 55, both with the date of surgery. A written transfer agreement sits in both records. The follow-up provider bills only after the first visit. Split billing does not apply to 0 day codes, and the two payments cannot exceed the global amount.
What do you need from an orthopedic practice to start?
A signed BAA, a user for your biller in your EHR, practice management system and clearinghouse, your payer contracts and fee schedules, the hospitals and surgery centers where your surgeons operate with their credentialing status, your DME supplier details if you dispense braces, and your current authorization tracking. Bring an aging report and a denial report to the review if you have them.
Next step
See where your orthopedic claims are getting stuck.
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- A billing specialist reads your answers and replies by email.
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While you wait: see the sample weekly report or read how switching works. You can also download the sample weekly report (PDF).