Can Original Knee Society Scores Be Used to Estimate New 2011 Knee Society Scores?

Background

The Knee Society Score (KSS) instrument is one of the most commonly reported primary outcome measures for total knee arthroplasty (TKA). Originally developed in 1989, the KSS was expanded and updated in 2011; however, the original KSS does not directly translate into the 2011 KSS. To date, no conversion algorithm has been developed, hindering the ability of researchers to adopt the 2011 KSS while maintaining their historical/longitudinal original KSS data.

Questions/purposes

The purpose of this study is to develop regression equations to map the original KSS to the 2011 KSS, allowing original and 2011 KSS data sets to be combined.

Methods

In this multicenter, nonrandomized study, a convenience sample of 815 patients undergoing primary TKA completed the original KSS questionnaire and the 2011 KSS questionnaire. Additionally, patient gender, patient age, and patient ethnicity were recorded. These data were then used to generate regression models to estimate the 2011 objective and function KSS from the original KSS. Of the 815 study patients, 476 (58%) were female and 339 (42%) were male at an average age of 67 years (SD 9.4). Roughly half of patients were assessed preoperatively (430 of 815 [53%]) with the remaining patients assessed postoperatively (386 of 815 [47%]). The average followup for postoperative patients was 4.4 years (SD 3.5 years).

Results

We have created a spreadsheet that can be used by individuals with no statistical training to crosswalk the objective and function subscores from the original KSS to the 2011 KSS [Supplemental materials are available with the online version of CORR®.]. The predictive model very accurately estimated the 2011 objective score, on average, within 0.22 points on the 100-point 2011 objective KSS at the cohort or aggregate level. The objective model accurately estimated the 2011 objective KSS within 8.83 points, on average, of the actual 2011 objective KSS at the individual patient level. However, as a result of large outliers, 37% of the estimated 2011 objective KSS were greater than 10 points from the actual 2011 objective KSS. To illustrate, if you use the model to estimate the 2011 objective KSS on a cohort of 100 patients, a patient with an original objective KSS of 88 will have an estimated objective KSS between 79 and 97 points. On the other hand, if you calculate an average original objective KSS of 88 for all 100 patients, the estimated average 2011 objective KSS will be 88 for the group. The predictive model accurately estimated the 2011 function KSS within 0.14 points on the 1000-point 2011 function KSS at the cohort level. At the patient level, the 2011 function KSS was also estimated within 8.8 points of the actual 2011 function KSS. However, 43% of the estimated function scores were greater than 10 points of the actual 2011 function KSS.

Conclusions

Clinicians and researchers can input their original KSS with demographic data into these equations to estimate the 2011 KSS objective and function scores. The small prediction error of 0.22 points that we calculated indicates that these models can be used to estimate the 2011 objective and function KSS at the aggregated cohort level. Although the average error score was within 10 points at the individual patient level, there was a high percentage of large errors resulting from outliers in the data set. These outliers seemed to be related to patients with excellent range of motion who had substantial pain and limited function or patients who have poor range of motion with excellent function and little pain. This may be inherent with the KSS or with the study sample. Nevertheless, one must use caution when estimating at the patient level. Additionally, the accuracy of the prediction scores decreases if any of the demographic variables included in this study are not available.

     

Can Computer Assistance Improve the Clinical and Functional Scores in Total Knee Arthroplasty?

Background  

Surgical navigation in TKA facilitates better alignment; however, it is unclear whether improved alignment alters clinical evolution and midterm and long-term complication rates.     

Measuring Outcomes of Laparoscopic Anti-reflux Surgery: Quality of Life Versus Symptom Scores?

Introduction

Outcome following fundoplication for gastroesophageal reflux can be measured using objective tests, symptom scores and quality of life (QoL) measures. Which is best and how these assessments correlate is uncertain. To determine the utility of assessment measures we compared a general QoL measure (SF-36) and a disease-specific measure (GERD-hr-QoL) with symptom and satisfaction scores in individuals following fundoplication.

Methods

329 individuals underwent fundoplication between 2000 and 2015 in 2 centres in Australia and the Netherlands. Patients were assessed before and 3, 12 and 24 months after surgery using 10-point Likert scales to assess heartburn and satisfaction, the SF-36 questionnaire and the GERD-hr-QoL questionnaire. SF-36 scores were converted into component scores: Physical Component Scale (PCS) score and Mental Component Scale (MCS) score. Correlations between QoL measures and clinical outcomes were determined.

Results

Surgery relieved heartburn (7.0 vs. 0.0 median, P < 0.001) and patients were highly satisfied with the outcome (median 9.0). PCS and MCS scores improved after surgery (PCS 40.9 vs. 46.0, P < 0.001; MCS 47.6 vs. 50.3, P = 0.027). GERD-hr-QoL scores also improved after surgery (15.7 vs. 3.7, P < 0.001). Correlations between PCS and MCS scores versus heartburn and satisfaction scores were generally weak or absent. However, correlations between GERD-hr-QoL versus heartburn and satisfaction scores were moderate to strong.

Conclusion

Despite improvements in scores, the SF-36 correlated poorly with clinical outcome measures, and its use to measure outcome following fundoplication is questioned. However, the GERD-hr-QoL correlated well with the symptom scores, suggesting this disease-specific QoL measure is a better tool for assessing anti-reflux surgery outcome.

     

Do Surgeon Expectations Predict Clinically Important Improvements in WOMAC Scores After THA and TKA?

Background

Failure of THA or TKA to meet a patient’s expectations may result in patient disappointment and litigation. However, there is little evidence to suggest that surgeons can consistently anticipate which patients will benefit from those interventions.

Questions/purposes

To determine the ability of surgeons to identify, in advance of surgery, patients who will benefit from THA or TKA and those who will not, where ‘benefit’ is defined as a clinically important improvement in a validated patient-reported outcomes score.

Methods

In this prospective study, eight high-volume orthopaedic surgeons completed validated THA and TKA expectations questionnaires (score 0–100, 100 being the highest expectation) as part of preoperative assessment of all their patients scheduled for a THA or TKA and enrolled in the Hospital for Special Surgery institutional registry. Enrolled patients completed the WOMAC preoperatively and at 2 years. Successful outcomes were defined as achieving the minimum clinically important difference (MCID) in WOMAC pain and function subscales. Sensitivity, specificity, and receiver operating characteristic (ROC) curves were used to evaluate the ability of surgeons’ expectation scores to identify patients likely to achieve the MCID on the WOMAC scale. Analyses were run separately for patients having THA and TKA. We enrolled 259 patients undergoing THA and 247 undergoing TKA, of whom 77% (n = 200) and 77% (n = 191) completed followup surveys 2 years after their procedures, respectively.

Results

Surgeons’ expectation scores effectively anticipated patients who would improve after THA, but they were no better than chance in identifying patients who would achieve the MCID on the WOMAC score 2 years after TKA. For patients having THA, the areas under the ROC curve were 0.67 (95% CI, 0.53–0.82; p = 0.02) and 0.74 (95% CI, 0.63–0.85; p < 0.01) for WOMAC function and pain outcomes, respectively, indicating good accuracy. Sensitivity and specificity were maximized on WOMAC pain and function scores (sensitivity = 0.69, specificity = 0.72, both for pain and function) at an expectations score of 83 or greater of 100. Surgeons’ expectations were more accurate for patients who were men, who had a BMI less than 30 kg/m², who had more than one comorbidity, and who were older than 65 years. For patients having TKA, surgeons’ expectation scores were not better than chance for identifying those who would experience a clinically important improvement on the WOMAC scale (area under ROC curve: Function = 0.51, [95% CI, 0.42–0.61], p = 0.78; Pain = 0.51, [95% CI, 0.40–0.61], p = 0.92).

Conclusions

Most patients having THA and TKA achieved the MCID improvement after surgery. However, the inability of surgeons’ expectation scores to discriminate accurately between patients who benefit and those who do not among patients scheduled for THA who are young, with no comorbidities, and with elevated BMIs, and among all patients scheduled for TKA, calls for surgeons to spend more time with these patients to fully understand and address their needs and expectations. Using standardized assessment tools to compare surgeons’ expectations and those of their patients may help focus the surgeon-patient discussion further, and address patients’ expectations more effectively.

Level of Evidence

Level II, therapeutic study.

     

What Factors Predict Improvements in Outcomes Scores and Reoperations After the Bernese Periacetabular Osteotomy?

Background

The Bernese periacetabular osteotomy (PAO) has entered its fourth decade and is frequently used for corrective osteotomy in patients with acetabular dysplasia. Although our capacity to preserve the joint after corrective osteotomy is excellent, gaining a better understanding on how well patients function after this surgery is important as well.

Questions/purposes

(1) What changes in patient-reported outcomes scores occur in patients treated with PAO for hip dysplasia in the setting of a single-surgeon practice? (2) What are the predictors of clinical function and survivorship?

Methods

All 67 patients presenting to a single surgeon’s clinic with hip dysplasia treated with PAO between October 2005 and January 2013 were prospectively followed. Baseline demographic data as well as pre- and postoperative radiographic and functional measurements were obtained with a minimum of 1-year followup. Radiographic criteria included Tönnis grade, Tönnis angle, minimum joint space width, center-edge angle, presence of crossover sign, medial translation of the hip center, and alpha angle. We also used validated outcome measures including the WOMAC, the UCLA Activity Scale, and the SF-12. Multiple regression analysis was used to determine predictors of functional outcome scores.

Results

There were increases in WOMAC, UCLA, and SF-12 Physical scores. Higher preoperative alpha angle was associated with a lower postoperative WOMAC score (β = −0.47; 95% confidence interval [CI], −0.92 to −0.02; R² = 0.08; p = 0.04). The 5-year Kaplan-Meier survivorship was 94.1% (95% CI, 90.7–97.5) with reoperation (ie, hip arthroscopy and/or total hip arthroplasty) used as the endpoint for failure. With the limited numbers available, we could not identify any demographic or radiographic factors associated with reoperation.

Conclusions

Overall survivorship for the PAO at our center at 5 years is comparable to other clinical series with overall functional scores improving. A greater alpha angle preoperatively was associated with poorer patient-reported outcome scores. Further research is needed to determine how and when intraarticular cartilage damage associated with dysplasia needs to be addressed.

Level of Evidence

Level IV, therapeutic study.     

Probability Scores and Diagnostic Algorithms in Pulmonary Embolism: Are They Followed in Clinical Practice?

IntroductionClinical probability scores (CPS) determine the pre-test probability of pulmonary embolism (PE) and assess the need for the tests required in these patients. Our objective is to investigate if PE is diagnosed according to clinical practice guidelines.Materials and methodsRetrospective study of clinically suspected PE in the emergency department between January 2010 and December 2012. A D-dimer value ≥500 ng/ml was considered positive. PE was diagnosed on the basis of the multislice computed tomography angiography and, to a lesser extent, with other imaging techniques. The CPS used was the revised Geneva scoring system.ResultsThere were 3924 cases of suspected PE (56% female). Diagnosis was determined in 360 patients (9.2%) and the incidence was 30.6 cases per 100 000 inhabitants/year. Sensitivity and the negative predictive value of the D-dimer test were 98.7% and 99.2% respectively. CPS was calculated in only 24 cases (0.6%) and diagnostic algorithms were not followed in 2125 patients (54.2%): in 682 (17.4%) because clinical probability could not be estimated and in 482 (37.6%), 852 (46.4%) and 109 (87.9%) with low, intermediate and high clinical probability, respectively, because the diagnostic algorithms for these probabilities were not applied.ConclusionsCPS are rarely calculated in the diagnosis of PE and the diagnostic algorithm is rarely used in clinical practice. This may result in procedures with potential significant side effects being unnecessarily performed or a high risk of underdiagnosis.     

Can the Oxford Scores Be Used to Monitor Symptomatic Progression of Patients Awaiting Knee or Hip Arthroplasty?

We report the week-to-week variation of the Oxford Knee and Oxford Hip Score (OKS, OHS) in individuals with severe osteoarthritis. People waitlisted for knee (n = 51) or hip arthroplasty (n = 52) were assessed twice, 1-week apart. There were no major week-to-week systematic biases in the scores. Limits of agreement (LOA) for both scores were wide (OKS, − 9.5 to 6.6; OHS, − 7.7 to 7). For most individual questions, the answers varied by ≤ 1 point in over 90% of participants. The week-to-week 95% LOA for the Oxford scores are unacceptably large, but variations within the individual questions are minimal. Consequently, reference to variation in the individual questions may be more useful for monitoring a patient's preoperative clinical change than changes in the total Oxford score. We conclude that the total scores are not suitable for monitoring the progression of OA in individual patients.     

Preoperative Leucocyte-Based Inflammatory Scores in Patients with Colorectal Liver Metastases: Can We Count on Them?

World Journal of Surgery - Neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and lymphocyte-to-monocyte ratio (LMR) have been identified as potential prognostic factors for...     

Outcome Scores Collected by Touchscreen: Medical Audit as it Should be in the 21st Century?

INTRODUCTION

Collecting outcome scores in paper form is fraught with difficulty. We have assessed the feasibility of, and patient''s attitude towards, entering scores using a touchscreen.

PATIENTS AND METHODS

A touchscreen was installed in the orthopaedic out-patient clinic. If relevant, patients were asked to complete either an Oswestry Disability Index (ODI) or Oxford Shoulder Score (OSS) using the screen. Patients were given written instructions and their hospital number by the receptionist who had no further input. Scores were completed with two identifiers. A paper questionnaire was used to assess computer experience and attitude towards the touchscreen.

RESULTS

A total of 1348 patients, average age 50 years, successfully completed a score in the first 12 months. One-third were over 60 years. Overall, 91% correctly entered their hospital number and date of birth, falling to 84% in patients over 70 years. All patients were identifiable. The average time to complete the scores was 4.7 min rising with age. Of 170 patients completing the paper assessment of the touchscreen, one-third had little or no experience of computers and a third were over 60 years. Of patients, 93% were willing to repeat the score using the touchscreen to monitor progress. Two-thirds found it easier to use than expected. Only 10% would prefer a paper score. These results were maintained among patients over 60 years. Only two were unable to complete the score and 80% of those potentially eligible did so. The remainder were called to clinic before the touchscreen was free.

CONCLUSIONS

Orthopaedic outcome scores can be collected in very large volumes using a touchscreen. Data are then in an immediately usable form. The method is acceptable to patients, independent of age and computer experience. Even in the oldest patients, the accuracy is higher than for paper versions of the score. Combined with operative data, this simple method has the potential to provide a very powerful audit tool indeed.     

A Test Case: Does the Availability of Visual Feedback Impact Grip Strength Scores When Using a Digital Dynamometer?

A cross-sectional, quantitative study of clinical measurement utility. New technological advances can challenge the efficacy of even the most widely accepted and respected tests. For example, grip strength instruments offer digital or computerized displays, precision scoring, and varied interfaces that differ from traditional Jamar™ dynamometers (Lafayette, IN). This test case explores how the opportunity to view grip strength scores during testing can influence outcomes. One hundred forty-six healthy subjects, aged 18-24 years, were tested for grip strength under visual feedback and no visual feedback conditions, using the JTech Grip Dynamometer (Salt Lake City, UT). Participants achieved a small, yet statistically significant, 1.74 lb stronger grip score with visual feedback (p < 0.002). The order of grip testing conditions yielded no statistically significant differences (p = 0.559). These findings suggest the need to consider how new features, unavailable with the analog Jamar™ dynamometer and unaccounted for in existing clinical guidelines could potentially influence grip scores.

Level of evidence

Not applicable.