Same Day versus Staged Total Knee Arthroplasty: Do Cost Savings Justify the Risk?

Comparison of the Cost-Effectiveness and Safety between Staged Bilateral Total Knee Arthroplasty and Simultaneous Bilateral Total Knee Arthroplasty: A Retrospective Cohort Study between 2001 and 2022

A substantial proportion of Hong Kong's aging population suffers from osteoarthritis in both knees. Bilateral total knee arthroplasty (BTKA) is a surgical option for addressing this condition and can be performed via two approaches: simultaneous BTKA (SimBTKA) and staged BTKA (StaBTKA). We compared the cost-effectiveness and safety of these two methods in our institution. We retrospectively reviewed 2,372 patients (SimBTKA, 772; StaBTKA, 1,600; females, 1,780; males, 592; mean age at SimBTKA, 70.4 ± 7.99 years; mean age at StaBTKA, 66.4 ± 7.50 years; p < 0.001) who underwent BTKA in our institution from 2001 to 2022. Patients were categorized according to the surgical approach. Patients undergoing BTKA in our institution were included. Particularly for SimBTKA, patients were assessed by anesthetists to be medically fit before undergoing the procedure according to their age, American Society of Anesthesiologists status, and osteoarthritis severity. The primary outcome was the length of stay (LOS) after surgery. The secondary outcomes were the 30-day unintended readmission, intensive care unit (ICU) admission, and death. SimBTKA had a shorter mean total LOS (acute hospital + rehabilitation center; SimBTKA, 13.09 days; StaBTKA, 18.12 days; p < 0.001) and mean LOS in acute hospital (SimBTKA, 7.70 days; StaBTKA, 10.42 days; p < 0.001). However, no significant difference was found in the mean LOS in rehabilitation centers (SimBTKA, 5.47 days; StaBTKA, 6.32 days; p > 0.05) between the two approaches. The 30-day unintended readmission rate was lower in SimBTKA (SimBTKA, 2.07%; StaBTKA, 3.30%; odds ratio [OR] = 1.60; p > 0.05) but statistically insignificant. SimBTKA was less costly than StaBTKA by US$ 8,422.22 per patient. No significant differences in ICU admission and death rates were found (p > 0.05) between the two groups. SimBTKA had a shorter LOS and lower cost than StaBTKA and comparable complication rates. Therefore, SimBTKA should be indicated in medically stable patients.

Subsequent total joint arthroplasty: Are we learning from the first stage?

BACKGROUND

With the increasing incidence of total joint arthroplasty (TJA), there is a desire to reduce peri-operative complications and resource utilization. As degenerative conditions progress in multiple joints, many patients undergo multiple procedures.

AIM

To determine if both physicians and patients learn from the patient's initial arthroplasty, resulting in improved outcomes following the second procedure.

METHODS

The institutional database was retrospectively queried for primary total hip arthroplasty (THA) and total knee arthroplasty (TKA). Patients with only unilateral THA or TKA, and patients undergoing same-day bilateral TJA, were excluded. Patient demographics, comorbidities, and implant sizes were collected at the time of each procedure and patients were stratified by first vs second surgery. Outcome metrics evaluated included operative time, length of stay (LOS), disposition, 90-d readmissions and emergency department (ED) visits.

RESULTS

A total of 642 patients, including 364 undergoing staged bilateral TKA and 278 undergoing bilateral THA, were analyzed. There was no significant difference in demographics or comorbidities between the first and second procedure, which were separated by a mean of 285 d. For THA and TKA, LOS was significantly less for the second surgery, with 66% of patients having a shorter hospitalization (P < 0.001). THA patients had significantly decreased operative time only when the same sized implant was utilized (P = 0.025). The vast majority (93.3%) of patients were discharged to the same type of location following their second surgery. However, when a change in disposition was present from the first surgery, patients were significantly more likely to be discharged to home after the second procedure (P = 0.033). There was no difference between procedures for post-operative readmissions (P = 0.438) or ED visits (P = 0.915).

CONCLUSION

After gaining valuable experience recovering from the initial surgery, a patient's perioperative outcomes are improved for their second TJA. This may be the result of increased confidence and decreased anxiety, and it supports the theory that enhanced patient education pre-operatively may improve outcomes. For the surgical team, the second procedure of a staged THA is more efficient, although this finding did not hold for TKA.

Cost, safety, and rehabilitation of same-stage, bilateral total knee replacements compared to two-stage total knee replacements

Background

Many patients experience bilateral knee osteoarthritis and require bilateral total knee replacement (TKR). Same-stage, bilateral TKR is proposed to be a cost-effective and safe solution compared to two-stage, but conflicting results in the literature are reported. We aim to compare the costs, safety, and rehabilitation performance of patients in same-stage versus two-stage, bilateral TKR with our centre’s perioperative protocol.

Materials and methods

We retrospectively reviewed 175 patients (95 same-stage, 80 two-stage) who had undergone bilateral TKR in our centre. Patient selection for same-stage, bilateral TKR was strictly protocol-driven and required fulfilment of all criteria, including age < 75 years, American Society of Anesthesiologists (ASA) grade 1 or 2, body mass index (BMI) < 40, and having non-complex arthritis. All patients followed a standardised pre-operative, intra-operative, and post-operative Enhanced Recovery After Surgery (ERAS) protocol. The cost, safety profiles, and rehabilitation outcomes were compared between the same-stage and two-stage groups.

Results

The same-stage, bilateral TKR reduced the length of hospital stays by 5.71 days per patient, decreased the operation time by 27.4 min, saved 3.34 (18.6%) physiotherapy sessions, and 3.78 (51.5%) occupational therapy sessions. The same-stage group experienced a higher haemoglobin drop but no significant difference in transfusion percentage, transfusion volume, complication rate, and readmission rate. The two-stage subgroup with anaesthetic risk, age, and BMI similar to the same-stage group showed the same results. Same-stage, bilateral TKR patients experienced no significant difference in final post-operative pain levels and rehabilitation outcomes as two-stage TKR patients.

Conclusion

This study showed that same-stage, bilateral TKR can reduce costs, with similar safety profiles and rehabilitation outcomes compared to the two-stage, bilateral TKR.