CPT code 01210: Open hip procedure anesthesia billing guide

Key Takeaways

CPT code 01210 covers anesthesia for open procedures on the hip joint that don’t have a more specific code, as defined by the AMA.

The code carries 6 base units. Reimbursement equals (base units + time units) multiplied by the CY2026 national conversion factor of about $20.50.

Modifier selection is payer-specific: Medicare requires AA, QZ, QK, QX, QY, or AD depending on provider type and supervision arrangement.

Revision surgery on a total hip arthroplasty has its own code, 01215, so don’t default to 01210 for those cases.

CPT code 01210 is the anesthesia code for open procedures on the hip joint that don’t fit a more specific code. It carries 6 base units under the ASA Relative Value Guide.

01210 belongs to a family of “not otherwise specified” anesthesia codes. They exist so coders always have a billable option when a procedure doesn’t match a named descriptor. It applies to open surgical approaches only. The AMA’s CPT code set lays out the full anesthesia section if you want the broader context.

What CPT code 01210 actually covers

The official AMA descriptor for CPT code 01210 reads: Anesthesia for open procedures on hip joint; not otherwise specified. It sits in the CPT anesthesia subsection for procedures on the pelvis and hip joint.

Nearby codes describe more specific hip procedures. As a base anesthesia code, it’s reported once per anesthetic episode, regardless of how long the case runs.

That “not otherwise specified” qualifier matters. Use 01210 only when the open hip procedure isn’t captured by a more specific sibling code. That includes 01200 for closed hip procedures, 01212 for hip disarticulation, and 01215 for revision total hip arthroplasty. Choosing 01210 when a more specific code exists raises the odds of a claim edit or denial.

Anesthesia type isn’t restricted here. The code applies whether the provider gives general anesthesia, regional anesthesia, or monitored anesthesia care, as long as the approach is open.

Orthopedic and sports medicine practices should confirm the surgical approach, open versus arthroscopic, before selecting this code. Dedicated sports medicine software makes that distinction easy to track case by case.

Base units decide most of the reimbursement math

CPT code 01210 carries 6 base units, consistent with the American Society of Anesthesiologists (ASA) Relative Value Guide. Base units reflect the complexity and risk inherent to the anatomical site and procedure type, independent of how long the case takes.

Reimbursement for anesthesia isn’t calculated like a standard CPT service. The formula is:

Anesthesia time begins when the provider starts preparing the patient in the operating room, or an equivalent area. It ends when the provider is no longer in personal attendance. Commercial payers may define start and stop time differently than Medicare, so verify each payer’s anesthesia time policy before billing.

The Medicare conversion factor updates every year through the CMS Physician Fee Schedule. It varies by geographic locality using practice cost indices. Pull the current year’s rate from CMS rather than relying on a prior-year figure.

For a free lookup tool that imports CMS data directly, FastRVU’s RVU lookup is worth bookmarking.

Modifiers make or break a 01210 claim

Modifier selection depends on provider type, physician anesthesiologist versus CRNA, and the supervision arrangement in place. Missing or incorrect modifiers are one of the top denial triggers for 01210 claims under Medicare. The applicable modifiers are:

Commercial insurers may not recognize every Medicare anesthesia modifier, so confirm each payer’s policy before submitting. QK and QX are always paired: when the anesthesiologist bills QK, the CRNA bills QX for the same case. Billing QK without a matching QX claim, or the reverse, triggers a medical direction mismatch edit.

Qualifying circumstances that add to the base

Qualifying circumstance codes are add-on codes reported alongside 01210 when specific conditions raise the complexity or risk of the anesthesia service. They aren’t automatic; documentation has to support their use.

For hip fracture cases, 99100 commonly applies since elderly patients make up a large share of open hip procedures. 99140 may apply for urgent fracture repairs where a delay poses meaningful risk. Confirm the documentation is explicit before appending any qualifying circumstance code; a vague reference to age or urgency won’t survive most payer edits.

ICD-10 codes that justify a 01210 claim

Payers confirm medical necessity by checking that the ICD-10 diagnosis code supports the procedure being billed. For CPT code 01210, the paired diagnosis should reflect a condition requiring open surgical intervention at the hip joint. The most common pairings are:

Payer claim edits for ICD-10/CPT combinations change with annual LCD and NCD updates. Verify the pairing against your payer’s current edits before submitting.

Specificity requirements shift by diagnosis category the same way they do for joint conditions like M36.4. Here, the rule is the same. Laterality and encounter type, initial versus subsequent versus sequela, must be fully specified, or the claim rejects at the front end.

Documentation Medicare expects to see

Three documentation records are required for every 01210 claim. They are the pre-anesthesia evaluation, the intraoperative anesthesia record, and the post-anesthesia note. Missing any one of these is a common audit finding, and a basis for recoupment under Medicare’s anesthesia documentation standards.

For hip cases moving into post-op rehab, practices running physical therapy EMR alongside their surgical record keep the whole episode connected. That’s useful when a payer asks for documentation later.

• Pre-anesthesia evaluation: Documents the patient’s medical history, airway assessment, ASA physical status classification, and the anesthesia plan. Must be completed before the procedure by the billing provider.
• Intraoperative anesthesia record: Captures start and stop times, anesthesia agents used, vital signs, fluid management, and any intraoperative events. The billed time units come directly from this record.
• Post-anesthesia note: Documents the patient’s condition at transfer of care, including level of consciousness, vital signs, pain level, and any complications. Must be completed before the patient leaves the anesthesia provider’s care.
• Supervision documentation (if applicable): For medical direction cases (QK/QX or QY), document that the seven required elements of medical direction were performed: pre-anesthesia evaluation, prescription of the anesthesia plan, personal participation in the most demanding portions, monitoring the course of anesthesia, remaining present for emergence, providing post-anesthesia care, and not directing more than four concurrent procedures.
• HIPAA-compliant claim submission: Electronic claims go through the standard HIPAA 837P transaction format. Review HIPAA compliance for medical offices to confirm your practice meets electronic submission standards.

For multi-location surgical practices, consistent documentation templates across sites cut audit risk. Standardizing pre-anesthesia evaluation forms with digital pre-anesthesia forms tied to the clinical record reduces the transcription errors that lead to modifier mismatches.

A HIPAA compliance checklist for your billing workflow is worth revisiting each year alongside payer policy updates.

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Practice management software like Pabau helps surgical and anesthesia practices track procedure codes, modifiers, and documentation requirements in one place, so fewer claims come back for missing information.

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When 01210 is the right call, and when it isn’t

CPT code 01210 applies to open surgical procedures on the hip joint that no more specific anesthesia code captures. Its “not otherwise specified” qualifier works as a catch-all within the hip joint subsection. Procedures that may fall under 01210 include:

• Open reduction of hip joint fractures not involving arthroplasty (hip arthroplasty uses 01214)
• Open synovectomy of the hip joint
• Open debridement or lavage of the hip joint
• Open capsular repair or contracture release
• Open procedures for hip dysplasia in pediatric patients not otherwise described
• Open revision procedures on the hip joint other than revision total hip arthroplasty, which has its own code, 01215

The key question is whether a more specific sibling code applies. Use 01200 for closed procedures, 01214 for total hip arthroplasty, 01215 for revision of that arthroplasty, or 01212 for hip disarticulation. If none of those fit and the approach is open, 01210 is correct.

Coding resources such as the AAPC Codify CPT lookup let coders quickly review adjacent codes in the hip joint subsection. That confirms the right selection fast.

Where 01210 sits among its sibling hip anesthesia codes

Knowing where 01210 sits in the hip joint anesthesia code family prevents upcoding errors and keeps the most specific code on the claim. The table below compares the primary sibling codes.

01214, for total hip arthroplasty, carries 8 base units versus 01210’s 6, reflecting its higher procedural complexity. 01215 covers revision surgery on that same arthroplasty, and it deserves its own line. Reporting a revision case under 01210 misses a more specific code that actually fits.

Confirm the documented procedure matches a code’s specific descriptor before you submit the claim.

The denial patterns that keep coming back

Claim denials for 01210 cluster around a predictable set of errors. Practices that audit their own claims against these patterns before submission cut their denial rate significantly.

• Wrong code selection: Reporting 01210 when 01214 (total hip arthroplasty), 01215 (revision arthroplasty), or 01212 (hip disarticulation) applies. The “not otherwise specified” descriptor doesn’t override a more specific code. This trips outpatient code editor (OCE) specificity checks.
• Missing anesthesia modifier: Submitting 01210 to Medicare without an AA, QZ, QK, QX, QY, or AD modifier. The modifier tells Medicare the provider type and payment methodology. Missing it usually triggers an automatic rejection.
• Modifier pairing errors: Filing QK without the corresponding QX from the CRNA, or the reverse. Medicare cross-references both claims, and a solo QK claim gets paid at a reduced rate or denied outright.
• ICD-10 mismatch: Pairing 01210 with a diagnosis that doesn’t support an open hip joint procedure, for example a soft tissue diagnosis unrelated to the hip joint. The medical necessity link between diagnosis and surgical approach has to be clear.
• Incorrect time unit calculation: Rounding anesthesia time up rather than down, or miscounting 15-minute increments. Payer policy on rounding the final partial unit varies, so confirm it before billing.
• Unbundling the qualifying circumstance: Appending 99100 to a case where documentation doesn’t clearly state the patient’s age or the specific circumstance. Add-on code claims without supporting documentation are vulnerable to audit and recoupment.

Practices that have moved their surgical documentation into structured electronic records report fewer front-end rejections. Modifier fields and time capture sit inside the workflow instead of being added after the fact.

Practice management software that ties procedure codes to documentation is one of the most direct ways to cut denial rates. That holds across a whole claims portfolio, not just one code.

Conclusion

CPT code 01210 has a narrow job: open procedures on the hip joint that no more specific code describes. The real billing complexity comes from what surrounds it. Modifier selection, qualifying circumstances, ICD-10 pairing, and documentation all have to hold up under a payer audit.

Pabau’s claims management software keeps modifier fields, time units, and documentation links attached to the claim from the point of care. Nothing has to be reconstructed after a denial lands. If tightening 01210 billing accuracy is on your list, book a demo. See how Pabau tracks procedure codes across a multi-provider surgical team.

Continue your research

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Want cleaner pre-anesthesia intake records? The medical review of systems template keeps documentation consistent across providers before a case starts.

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