Release Notes:
Measure Information Form
Version 2027A
Measure Set: Total Hip and Total Knee Replacement Outpatient (THKR-OP)
Set Measure ID: THKR-OP-5
| Set Measure ID |
Performance Measure Name |
THKR-OP-5a |
Postoperative Functional/Health Status Assessment-Hip and Knee Overall |
THKR-OP-5b |
Postoperative Functional/Health Status Assessment-Hip |
THKR-OP-5c |
Postoperative Functional/Health Status Assessment-Knee |
Performance Measure Name: Postoperative Functional/Health Status Assessment
Description: Patients who completed the general health and joint specific functional status assessments, at 1 year (300-425 days) after surgery, as specified below:
Hips: [VR-12 or PROMIS-Global] AND [HOOS Jr. (6 questions) or HOOS Pain, Function Daily Living Subscales (27 questions)]
Knees: [VR-12 or PROMIS-Global] and [KOOS Jr. (7 questions) or KOOS Stiffness, Pain, Function Daily Living Subscales (28 questions)]
The assessment tool must reflect the status of the patient’s health condition, health behavior, or experience with health care from the patient’s perspective, without interpretation of the patient’s response by a clinician or anyone else. The assessment can be completed by phone, mail, email, or in-person.
Rationale: Elective total hip and knee replacement procedures seek to relieve pain and improve function, underscoring the importance of evaluating these outcomes pre and post surgery (Ayers, 2017). Patient-reported outcome measures (PROMs) are standardized instruments that capture a patient’s perspective on their health status including symptoms, physical function, and quality of life.
The Centers for Medicare & Medicaid Services (CMS) has finalized policies to expand the collection and reporting of patient-reported outcomes (PROs) for total hip and total knee arthroplasty across multiple programs (CMS, 2025a, 2026a, 2026b, 2026c). This expansion reflects a national strategy to capture meaningful pre and postoperative PROMs to support clinical care, shared decision-making, and hospital-level quality assessment for elective total hip and knee replacement procedures (Ayers, 2017; CMS, 2025b; Pasqualini et al., 2026).
Informed by the recommendations of the 2015 Patient Reported Outcomes Summit for Total Joint Arthroplasty (American Association of Hip and Knee Surgeons, 2015), this measure aims to advance postoperative PROM collection for total hip and knee arthroplasty procedures while accounting for the administrative burden associated with PRO data capture.
Type Of Measure: Process
Improvement Noted As: Increase in the rate
Numerator Statement:
Number of patients who completed the general health (VR-12 or PROMIS-Global) AND joint specific functional status assessments (HOOS Jr./subscales or KOOS Jr./subscales) at 1 year (300-425 days) after surgery.
Included Populations: Not applicable
Excluded Populations: None
Data Elements:
Denominator Statement: Patients who underwent a total hip or total knee replacement.
Included Populations:
Patients with a CPT® Code with Modifier as defined in Appendix A: Table 14.01b (Total Hip Replacements-OP), or Table 14.02b (Total Knee Replacements-OP), or Table 14.03b (Bilateral Hip Replacements-OP), or Table 14.04b (Bilateral Knee Replacements-OP)
Excluded Populations:
- Patients less than 18 years of age
- Patients a CPT® Code with Modifier as defined in Appendix A: Table 14.05b (Partial hip and partial knee replacements-OP), or Table 14.06b (Revision and resurfacing procedures-OP), or Table 14.07b (Removal of implanted devices/prostheses-OP)
- Patients with an ICD-10-CM Principal Diagnosis Code or ICD-10-CM Other Diagnosis Code as defined in Appendix A: Table 14.08 (Complication of Internal Fixation Device/Prosthesis), or Table 14.09 (Malignant neoplasm of the pelvis, sacrum, coccyx, lower limbs, or bone/bone marrow or a disseminated malignant neoplasm) or Table 14.10 (Fractures)
- Documentation that the patient expired after the principal procedure and prior to the end of the data collection period
Data Elements:
Risk Adjustment: No.
Data Collection Approach: Retrospective data sources for required data elements include administrative data and medical records.
Data Accuracy: Variation may exist in the assignment of ICD-10 codes; therefore, coding practices may require evaluation to ensure consistency.
Measure Analysis Suggestions: None
Sampling: Yes. Please refer to the measure set specific sampling requirements and for additional information see the Population and Sampling Specifications Section.
Data Reported As: Aggregate rate generated from count data reported as a proportion. Proportion for hip replacements, proportion for knee replacements and aggregated proportion for hip & knee replacements.
Selected References:
- American Association of Hip and Knee Surgeons. (2015). Patient reported outcomes summit for total joint arthroplasty. https://www.aahks.org/wp-content/uploads/2015/09/AAHKS-2015-Outcomes-Summit-Report.pdf
- Ayers, D. C. (2017). Implementation of patient-reported outcome measures in total knee arthroplasty. Journal of the American Academy of Orthopaedic Surgeons, 25 (Suppl. 1), S48–S50. https://doi.org/10.5435/JAAOS-D-16-00631
- Centers for Medicare & Medicaid Services. (2025a). Hospital inpatient quality reporting program. https://www.cms.gov/medicare/quality/initiatives/hospital-quality-initiative/inpatient-reporting-program
- Centers for Medicare & Medicaid Services. (2025b). Risk-standardized patient-reported outcome-based performance measure (PRO-PM) following elective primary total hip arthroplasty (THA) and/or total knee arthroplasty (TKA) in the HOPD setting (THA/TKA PRO-PM) (OP-42) (Version 1.0). QualityNet. https://qualitynet.cms.gov/files/6766d395a9dd1a5308128737?filename=HOQR_THATKA_PRO-PM_MIF_v.1.pdf
- Centers for Medicare & Medicaid Services. (2026a). Ambulatory surgical center quality reporting program. https://www.cms.gov/medicare/quality/initiatives/asc-quality-reporting
- Centers for Medicare & Medicaid Services. (2026b). Hospital outpatient quality reporting program. https://www.cms.gov/medicare/quality/initiatives/hospital-quality-initiative/hospital-outpatient-quality-reporting-program
- Centers for Medicare & Medicaid Services. (2026c). TEAM (Transforming episode accountability model). https://www.cms.gov/priorities/innovation/innovation-models/team-model
- Pasqualini, I., Elmenawi, K. A., Khan, S. T., Gudapati, L. S., & Piuzzi, N. S. (2026). Implementing the total hip and knee arthroplasty patient-reported outcome-based performance measure in outpatient and ambulatory surgical center settings: A practical review of new Centers for Medicare and Medicaid Services policies. The Journal of Arthroplasty, 41 (3), 668–673. https://doi.org/10.1016/j.arth.2025.10.023
Measure Algorithm:
THKR-OP-5: Algorithm Narrative
THKR-OP-5: Postoperative Functional/Health Status Assessment
Numerator: Number of patients who completed the general health and joint specific functional status assessments at 1 year (300-425 days) after surgery.
Denominator: Patients who underwent a total hip or total knee replacement.
Variable Key: Post Assessment Day
Stratification Table:
Measure ID = THKR-OP-5a, Stratified Measure Name = Overall Rate
Measure ID = THKR-OP-5b, Stratified Measure Name = Hip
Measure ID = THKR-OP-5c, Stratified Measure Name = Knee
1. Start Postoperative Functional/Health Status Assessment logic. Run cases, which are included in the THKR Outpatient Initial Patient Population and pass the edits defined in the Clinical Data Processing Flow, through this measure.
2. Check ICD-10-CM Principal or Other Diagnosis Codes.
- If ICD-10-CM Principal or Other Diagnosis Codes is At least one on Table 14.10, the case will proceed to a Measure Category Assignment of B and will be Not In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If ICD-10-CM Principal or Other Diagnosis Codes is None on Table 14.10, the case will continue processing and proceed to Check Pre-Collection Mortality.
3. Check Pre-Collection Mortality
- If Pre-Collection Mortality is missing, the case will proceed to a Measure Category Assignment of X and Case Will Be Rejected. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Pre-Collection Mortality equals Y, the case will proceed to a Measure Category Assignment of B and will be Not In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to Step 9.
- If Pre-Collection Mortality equals N, the case will continue processing and proceed to Check CPT Code Procedure Date.
4. Check CPT Code Procedure Date.
- If CPT Code Procedure Date is Missing, the case will proceed to a Measure Category Assignment of X and Case Will Be Rejected. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If CPT Code Procedure Date equals UTD, the case will proceed to a Measure Category Assignment of D and will be In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If CPT Code Procedure Date is Non-UTD Value, the case will continue processing and proceed to Check Postoperative Assessments Completed.
5. Check Postoperative Assessments Completed.
- If Postoperative Assessments Completed is Missing, the case will proceed to a Measure Category Assignment of X and Case Will Be Rejected. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Postoperative Assessments Completed equals N, the case will proceed to a Measure Category Assignment of D and will be In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Postoperative Assessments Completed equals Y, the case will continue processing and proceed to Check Postoperative Assessments Completion Date.
6. Check Postoperative Assessments Completion Date.
- If Postoperative Assessments Completion Date is Missing, the case will proceed to a Measure Category Assignment of X and Case Will Be Rejected. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Postoperative Assessments Completion Date equals UTD, the case will proceed to a Measure Category Assignment of D and will be In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Postoperative Assessments Completion Date is Non-UTD Value, the case will continue processing and proceed to Check Post Assessment Day.
7. Post Assessment Day (in days) equals Postoperative Assessments Completion Date minus CPT Code Procedure Date.
8. Check Post Assessment Day.
- If Post Assessment Day is greater than or equal to 300 days and is less than or equal to 425 days, the case will proceed to a Measure Category Assignment of E and will be In Numerator Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
- If Post Assessment Day is less than 300 days or greater than 425 days, the case will proceed to a Measure Category Assignment of D and will be In Measure Population. For Overall Rate (THKR-OP-5a). Proceed to step 9.
9. Initialize the Measure Category Assignment for each strata measure (b-c) equals 'B'. Do not change the Measure Category Assignment that was already calculated for the overall rate (THKR-OP-5a).
10. Check Overall Rate Category Assignment.
- If Overall Rate Category Assignment equals B, the case will Stop processing.
- If Overall Rate Category Assignment equals D or E or X, the case will continue processing and proceed to Check CPT Codes with Modifier.
11. Check CPT Codes with Modifier.
- If CPT Codes with Modifier is On Table 14.02b, 14.04b, the case will continue processing and proceed to Check the Measure Category Assignment for THKR-OP-5c.
- If CPT Codes with Modifier is On Table 14.01b, 14.03b, the case will continue processing and proceed to Check the Measure Category Assignment for THKR-OP-5b.
12. Set the Measure Category Assignment for THKR-OP-5c equals Measure Category Assignment for measure THKR-OP-5a. For Stratified Measure THKR-OP-5c. Stop processing.
13. Set the Measure Category Assignment for THKR-OP-5b equals Measure Category Assignment for measure THKR-OP-5a. For Stratified Measure THKR-OP-5b. Stop processing.