Reliability of patient-reported complications following hip or knee arthroplasty procedures

BACKGROUND

Patient reported outcomes are increasingly used to assess the success of surgical procedures. Patient reported complications are often included as an outcome. However, these data must be validated to be accurate and useful in clinical practice.

METHODS

This was a retrospective descriptive study of 364 patients who had completed their six-month follow-up review questionnaire in the Arthroplasty Clinical Outcomes Registry, National (ACORN), an Australian orthopaedic registry. Patient-reported complications following total hip arthroplasty (THA) and total knee arthroplasty (TKA) were compared to surgeon-reported complications recorded in their electronic medical records at their various follow-up appointments. Sensitivity, specificity, positive predictive value and negative predictive value were calculated. Agreement was assessed using percentage agreement and Cohen's kappa.

RESULTS

Patient-reported data from the ACORN registry returned overall low sensitivity (0.14), negative predictive value (0.13) and kappa values (0.11), but very high specificity (0.98), positive predictive value (0.98) and agreement values (96.3%) for reporting of complications when compared to surgeon-reported data. Values varied depending on the type and category of complication.

CONCLUSION

Patients are accurate in reporting the absence of complications, but not the presence. Sensitivity of patient-reported complications needs to be improved. Greater attention to the clarity of the questions asked may help in this respect.

Infection burden in total hip and knee arthroplasties: an international registry-based perspective. Arthroplast Today. 2017;3:137-140. [PMID: 28695187 PMCID: PMC5485227 DOI: 10.1016/j.artd.2017.05.003]

Background

Infection remains a leading cause of failure of hip and knee replacements. Infection burden is the ratio of implants revised for infection to the total number of arthroplasties in a specific period, measuring the steady state of infection in a registry. We hypothesized infection burden would be similar among arthroplasty registries.

Methods

We evaluated publicly reported data from 6 arthroplasty registries (Australian Orthopaedic Association National Joint Replacement Registry [AOANJRR], New Zealand Joint Registry, Swedish Hip Arthroplasty Register, Swedish Knee Arthroplasty Register, National Joint Registry of England, Wales, Northern Ireland, and the Isle of Man, and the American Joint Replacement Registry) for revisions performed with an infection diagnosis over the last 6 years.

Results

The 2015 hip infection burden varied between registries from 0.76% (AOANJRR) to 1.24% (Swedish Hip Arthroplasty Register), and the unweighted overall average for hip infection burden was 0.97%. In 2012, 2013, and 2014, average hip infection burden held steady at 0.87%, 0.93%, and 0.94%, respectively, higher than the preceding 2 years. The 2015 knee infection burden varied from 0.88% (AOANJRR) to 1.28% (Swedish Knee Arthroplasty Register), and the unweighted average was 1.03%. In 2012, 2013, and 2014, knee infection burden was 1.04%, 1.11%, and 1.02%, respectively. These numbers were also higher than the preceding 2 years.

Conclusions

Infection burden may be one measure of the overall success in registry populations as well as monitoring the steady state of infection worldwide. Despite global efforts to reduce postoperative infection, infection burden has actually increased in the selected registries over time.

Comparing contemporary revision burden among hip and knee joint replacement registries

Background

Hip and knee arthroplasties are common and successful procedures, however, success and durability are not guaranteed. The revision burden, defined as the ratio of implant revisions to the total number of arthroplasties in a specific period, is a measure of the steady state of arthroplasty success in a given registry. This study examines the hypothesis that revision burden would be similar among contemporary joint replacement registries and improving over time compared with historic controls.

Methods

We evaluated the national joint registries of 5 health systems (Australian Orthopaedic Association National Joint Replacement Registry [AOANJRR]; National Joint Registry of England, Wales, Northern Ireland, and the Isle of Man; New Zealand Joint Registry [NZJR]; Swedish Hip Arthroplasty Register [SHAR] and Swedish Knee Arthroplasty Register [SKAR]; and the American Joint Replacement Registry [AJRR]) for hip and knee revision burden over the past 4 years or since registry inception. Historic controls were obtained from previously published reports.

Results

The 2014 hip revision burden varied from 9.7 percent (NJR) to 11.9 percent (NZJR), and the unweighted average was 10.4 percent. The 2011, 2012, and 2013 mean hip revision burden was 11.9, 11.9, and 11.4 percent. The 2014 knee revision burden varied from to 6.0 percent (NJR) to 8.1 percent (AJRR), and the unweighted average for the 5 registries studied was 7.0 percent. The 2011, 2012, and 2013 mean knee revision burden was 6.9, 7.0, and 7.0 percent. Historically, the observed hip revision burden was 15.8 percent and the knee revision burden 8.0 percent.

Conclusions

Revision burden has gradually decreased for hip replacements and has remained relatively constant for knee replacements both for the last 4 years and compared to historic controls. Knee revision burden was lower than hip revision burden for each period examined. Revision burden is one measure that may be helpful in following the effect of changes in surgical technique and implant design over time in registry populations and may be a helpful way to compare overall results between registries.

Survival outcomes of cemented compared to uncemented stems in primary total hip replacement

Total hip replacement (THR) is a successful and reliable operation for both relieving pain and improving function in patients who are disabled with end stage arthritis. The ageing population is predicted to significantly increase the requirement for THR in patients who have a higher functional demand than those of the past. Uncemented THR was introduced to improve the long term results and in particular the results in younger, higher functioning patients. There has been controversy about the value of uncemented compared to cemented THR although there has been a world-wide trend towards uncemented fixation. Uncemented acetabular fixation has gained wide acceptance, as seen in the increasing number of hybrid THR in joint registries, but there remains debate about the best mode of femoral fixation. In this article we review the history and current world-wide registry data, with an in-depth analysis of the New Zealand Joint Registry, to determine the results of uncemented femoral fixation in an attempt to provide an evidence-based answer as to the value of this form of fixation.