The Immediate Impact of Total Knee Arthroplasty Removal From the Medicare Inpatient-Only List on Patient Derived Functional Outcomes and Hospital Satisfaction

BACKGROUND

Total knee arthroplasty (TKA) is the standard of treatment for end-stage knee osteoarthritis. On January 1, 2018, the Centers for Medicare and Medicaid (CMS) officially removed TKA from their inpatient-only list. The clinical impact of this change is not fully understood yet.

METHODS

Electronic records were retrospectively reviewed for patients who underwent TKA between January 1 to June 30, 2017, or January 1 to June 30, 2018. Patients completed Function and Outcomes Research for Comparative Effectiveness in Total Joint Replacement surveys which assessed patient reported outcomes prior to and following TKA. Hospital statistics for the 2 time points were determined and compared. This was a single institution study resulting in 351 patients in the pre-CMS change group and 350 patients in the post-CMS change group.

RESULTS

Analysis of the pre-CMS and post-CMS transition cohorts indicated no significant difference in activities of daily living (ADLs), pain, or pain catastrophizing scale preoperatively or 12-months postoperatively. Additionally, there was no difference in the median change between preoperative and postoperative ADL scores (P = .866), yet pain scores approached significance with a P value of .054. The pre-CMS transition group stayed significantly longer in the hospital postoperatively and was more commonly discharged to a skilled nursing facility. No difference was seen in 30-day readmission rates (P = .253).

CONCLUSIONS

Results showed that patients had similar scores for ADL, quality of life, pain, and pain catastrophizing 12-months following their TKA. Movement of TKA from the Medicare inpatient only list did not have an immediate negative impact for patient reported outcomes and 30-day readmissions at our institution in the 6-month transition period.

Is the Centers for Medicare and Medicaid Services Hierarchical Condition Category Risk Adjustment Model Satisfactory for Quantifying Risk After Spine Surgery?

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) hierarchical condition category (HCC) coding is a risk adjustment model that allows for the estimation of risk-and cost-associated with health care provision. Current models may not include key factors that fully delineate the risk associated with spine surgery.

OBJECTIVE

To augment CMS HCC risk adjustment methodology with socioeconomic data to improve its predictive capabilities for spine surgery.

METHODS

The National Inpatient Sample was queried for spinal fusion, and the data was merged with county-level coverage and socioeconomic status variables obtained from the Brookings Institute. We predicted outcomes (death, nonroutine discharge, length of stay [LOS], total charges, and perioperative complication) with pairs of hierarchical, mixed effects logistic regression models-one using CMS HCC score alone and another augmenting CMS HCC scores with demographic and socioeconomic status variables. Models were compared using receiver operating characteristic curves. Variable importance was assessed in conjunction with Wald testing for model optimization.

RESULTS

We analyzed 653 815 patients. Expanded models outperformed models using CMS HCC score alone for mortality, nonroutine discharge, LOS, total charges, and complications. For expanded models, variable importance analyses demonstrated that CMS HCC score was of chief importance for models of mortality, LOS, total charges, and complications. For the model of nonroutine discharge, age was the most important variable. For the model of total charges, unemployment rate was nearly as important as CMS HCC score.

CONCLUSION

The addition of key demographic and socioeconomic characteristics substantially improves the CMS HCC risk-adjustment models when modeling spinal fusion outcomes. This finding may have important implications for payers, hospitals, and policymakers.