Ten-year results for a single-surgeon series of Scorpio non-restrictive geometry (NRG) posterior stabilised (PS) total knee replacement

Serial changes in patient-reported outcome measures and satisfaction rate during long-term follow-up after total knee arthroplasty: a systematic review and meta-analysis

PURPOSE

This study aimed to investigate the sequential changes in patient-reported outcome measures (PROMs) and the satisfaction rate during long-term follow-up after total knee arthroplasty (TKA).

METHODS

Studies published until December 2023 were searched in MEDLINE, EMBASE, SCOPUS and Cochrane Library. The inclusion criteria were TKA as the primary procedure, a final post-operative follow-up period of at least seven years and reporting of PROMs data. The exclusion criteria were studies not reporting serial data of the same patient cohort, studies without mid-term data, comparative studies and reviews, comments or practice guidelines. Heterogeneity was assessed with the I2 and tau2 statistics. The quality of each study was evaluated using the methodological index for non-randomized studies (MINORS) criteria. The follow-up periods were divided into short-term, mid-term and long-term. Data were synthesised by narrative reviews and random-effects meta-analysis using standardised mean difference.

RESULTS

Among the 13 studies included in the review, six were included in the meta-analysis. The overall PROMs were maintained until the mid-term (0.14; 95% CI [confidence interval], -0.05 to 0.34; I2 = 96%; tau2 = 0.10; P = 0.16), but declined in the long-term (-0.23; 95% CI -0.34 to -0.13; I2 = 88%; tau2 = 0.04; P < 0.0001). According to the subgroup analysis, pain improved from the short-term to mid-term (0.21; 95% CI 0.14 to 0.29; I2 = 0%; tau2 = 0). Subscales including function (-0.28; 95% CI -0.52 to -0.03; I2 = 94%; tau2 = 0.09) and objective measure (-0.23; 95% CI -0.31 to -0.15; I2 = 62%; tau2 = 0.01) declined from the mid-term to long-term. The patient satisfaction rate remained consistent throughout the study period.

CONCLUSIONS

The overall PROMs after TKA were maintained, with improvement observed in the pain subscale until the mid-term follow-up. However, in the long-term, overall PROMs, including function and objective measure, declined compared with those in the mid-term. Despite the decline in the physical aspects of PROMs over the long-term follow-up period, the patient satisfaction rate remained consistently high throughout the study period. Providing this information to patient pre-operatively may assist in establishing realistic expectations. Trial Registration This research was registered at PROSPERO (registration number: CRD42024578579).

Long-term outcomes of total knee arthroplasty in patients with windswept deformity

BACKGROUND

This study compared the functional outcomes, implant survival rates, and complications of total knee arthroplasty (TKA) performed in patients with windswept deformity (WSD) and non-WSD patients over at least 10 years of follow-up.

METHODS

From January 2008 to December 2010, 40 TKAs were performed in 20 patients with WSD (WSD group). Additionally, 60 propensity score-matched patients without WSD who had undergone primary bilateral TKA were chosen for the control group in a three-to-one ratio. Then, the functional outcomes, implant survival rates, and complications of TKA in the two groups were compared. The mean follow-up periods were 10.8 years in the WSD group and 11.5 years in the control group.

RESULTS

The mean Knee Society knee scores in the WSD and control groups improved from 37.7 to 38.1 points preoperatively to 79.5 and 79.2 points at final follow-up (p = 0.974), while the mean function scores in the WSD and control groups improved from 36.5 to 37.2 points preoperatively to 77.8 and 77.4 points at final follow-up (p = 0.863). Two knees in the WSD group required revision surgery, including one due to septic loosening and one due to aseptic loosening. Five knees in the control group required revision surgery, including three due to septic loosening and two due to aseptic loosening. Kaplan-Meier survivorship analysis with the revision of either component as an endpoint in the WSD and control groups estimated 95.0% and 95.8% chances of survival for 10 years, respectively (p = 0.824).

CONCLUSIONS

TKA performed in patients with WSD yielded good clinical outcomes and survivorship at least 10 years later.

LEVEL OF EVIDENCE

IV.

No higher tibial post fracture rate with highly cross-linked polyethylene inserts in total knee arthroplasty at a minimum 10-year follow-up

PURPOSE

The purpose of this study was to assess tibial post fracture between highly cross-linked polyethylene (HXPE) and conventional polyethylene inserts in consecutive posterior-stabilized (PS) total knee arthroplasty (TKA) over a minimum 10-years follow-up period.

METHODS

Between July 2008 and December 2011, a consecutive series of 3264 primary TKAs was performed in 2098 patients using a PS total knee prosthesis at a single institution. The final cohort was classified into the HXPE group (792 cases) and the conventional group (2113 cases) according to insert material used during the procedure.

RESULTS

The mean follow-up period was 11.4 years in the HXPE group and 11.8 years in the conventional group. Both cases of tibial post fracture occurred in the HXPE group, a complication rate of 0.25%. These two cases required replacement with a thicker tibial insert with retention of the femoral and tibial components. There were no cases of tibial post fracture in the conventional group.

CONCLUSION

There was no difference in tibial post fracture rate between the HXPE group and the conventional group in PS TKA on long-term follow-up.

LEVEL OF EVIDENCE

IV.

Long-term survivorship of total knee arthroplasty with a single-radius, high-flexion posterior stabilized prosthesis

BACKGROUND

The purpose of this study was to determine functional outcomes, implant survival rate, and complications of a single-radius, high-flexion posterior stabilized (PS) total knee prosthesis at a minimum follow up of 10 years for a consecutive series.

METHODS

This retrospective observational study included 395 consecutive patients who underwent 585 single-radius, PS total knee arthroplasties (TKAs) between January 2009 and December 2009. Their functional outcomes, implant survival rates, radiological findings, and complications were evaluated.

RESULTS

At a mean follow up of 11.2 years (range, 10.6-11.8 years), 395 (80.8%) patients were available for review. At final follow up, preoperative Knee Society knee scores were improved from 37.3 to 80.1 (P < 0.05) and function scores were improved from 35.7 to 80.5 points (P < 0.05). Sixteen knees (2.7%) in 15 patients required revision surgery due to 11 septic loosening (1.9%) and five aseptic loosening events (0.8%). Cumulative survival for the prosthesis was 97.3% for any cause at 10 years. A total of 34 radiolucent lines (5.8%) were detected an average of 2.4 years following surgery and radiological assessment did not reveal any evidence of component migration at final follow up.

CONCLUSIONS

Single-radius, high-flexion PS TKA showed good long-term survival rates and clinical outcomes. Further study is required to determine whether limited radiolucency findings at the tibial component-tibial plateau could progress to or result in the loosening of components.