Direct anterior approach improves in-hospital mobility following hemiarthroplasty for femoral neck fracture treatment.

INTRODUCTION: In elderly patients, an established treatment for femoral neck fractures is hip hemiarthroplasty (HHA) using the anterolateral approach (ALA). Early postoperative mobilization is crucial to reduce perioperative complications. The direct anterior approach (DAA) has been reported to facilitate early recovery of ambulation and is increasingly popular in elective hip surgery but rarely used in femoral neck fractures. The aim was to compare the outcome of the DAA and the ALA in patients treated for femoral neck fracture. MATERIALS AND METHODS: All HHAs with complete data sets were reviewed from a tertiary public healthcare institution (2013-2020). Propensity score matching was applied to compensate for possible confounders; outcome parameters were perioperative blood loss, postoperative mobility and pain. Secondary outcomes were duration of surgery, length of stay (LOS), complications, reoperation and mortality rates. RESULTS: There were 237 patients (mean age 85.8 years) available for analysis. The DAA group mobilized earlier during hospitalization (outside patient room: 50.6 vs 38.6%, p = 0.01; walking on crutches/walker: 48.1 vs 36.1%, p < 0.01), had shorter surgeries (DAA vs ALA: 72.5 vs 89.5 min, p < 0.001) and a trend towards fewer complications (32.9% vs 44.9%, p = 0.076). Blood loss (286 vs 287 ml), LOS (10.4 vs 9.5 days), pain (cessation of opioid medication: 2.9 vs 3.3 days post-op), revision (2.5 vs 3.2%) or mortality (30-days: 7.6 vs 5.7%) did not differ between patient groups. CONCLUSIONS: DAA for HHA led to earlier in-hospital mobility, shorter surgeries and a tendency towards fewer complications. No advantage was found regarding perioperative blood loss and pain.

Higher body mass index is associated with larger postoperative improvement in patient-reported outcomes following total knee arthroplasty.

BACKGROUND: Total knee arthroplasty is known to successfully alleviate pain and improve function in endstage knee osteoarthritis. However, there is some controversy with regard to the influence of obesity on clinical benefits after TKA. The aim of this study was to investigate the impact of body mass index (BMI) on improvement in pain, function and general health status following total knee arthroplasty (TKA). METHODS: A single-centre retrospective analysis of primary TKAs performed between 2006 and 2016 was performed. Data were collected preoperatively and 12-month postoperatively using WOMAC score and EQ-5D. Longitudinal score change was compared across the BMI categories identified by the World Health Organization. RESULTS: Data from 1565 patients [mean age 69.1, 62.2% women] were accessed. Weight distribution was: 21.2% BMI < 25.0 kg/m2, 36.9% BMI 25.0-29.9 kg/m2, 27.0% BMI 30.0-34.9 kg/m2, 10.2% BMI 35.0-39.9 kg/m2, and 4.6% BMI ≥ 40.0 kg/m2. All outcome measures improved between preoperative and 12-month follow-up (p < 0.001). In pairwise comparisons against normal weight patients, patients with class I-II obesity showed larger improvement on the WOMAC function and total score. For WOMAC pain improvements were larger for all three obesity classes. CONCLUSIONS: Post-operative improvement in joint-specific outcomes was larger in obese patients compared to normal weight patients. These findings suggest that obese patients may have the greatest benefits from TKA with regard to function and pain relief one year post-op. Well balanced treatment decisions should fully account for both: Higher benefits in terms of pain relief and function as well as increased potential risks and complications. Trial registration This trial has been registered with the ethics committee of Eastern Switzerland (EKOS; Project-ID: EKOS 2020-00,879).

Minimal important differences for the WOMAC osteoarthritis index and the Forgotten Joint Score-12 in total knee arthroplasty patients.

BACKGROUND: Total knee arthroplasty (TKA) is an effective treatment for end-stage osteoarthritis. Patient reported-outcome measures (PROMs) capture the patients' perception of the success of an intervention. The minimal important difference (MID) is an important characteristic of the PROM, which helps to interpret results. The aim of this study was to identify the MID for the Forgotten Joint Score-12 (FJS-12) and Western Ontario and McMaster Universities (WOMAC) osteoarthritis index. METHODS: Data were collected in a prospective cohort study. Patients were asked to complete the FJS-12, WOMAC osteoarthritis index and transition items evaluating change over time to determine the MID. We employed an anchor-based methodology relating score change to the response categories of the transition items using both binary logistic regression and receiver operating characteristic (ROC) analysis. RESULTS: Data from 199 patients were analysed. Mean age was 72.3 years, 58% were women. Employing binary logistic regression the MID for the FJS-12 was 10.8 points, for the WOMAC pain score 7.5 points and for the WOMAC function score 7.2 points. ROC analyses found a MID of 13.0 points for the FJS-12, 12.5 points for WOMAC pain and 14.7 points for WOMAC function. CONCLUSION: We report MIDs for the FJS-12 and the WOMAC Pain and Function scales in a TKA patient cohort, which can be used to interpret meaningful differences in score. In line with previous research, we found more advanced statistical methods to result in smaller MID estimates for both scores. TRIAL REGISTRATION: Written consent for this study was obtained from all participants and ethical approval was granted by the local ethics committee (Ethikkommission St. Gallen; EKSG 14/973; Registered 03 July 2014; http://www.sg.ch/home/gesundheit/ethikkommission.html).

Single-item satisfaction scores mask large variations in pain, function and joint awareness in patients following total joint arthroplasty.

INTRODUCTION: Single-item questions assessing patient satisfaction following total hip or knee arthroplasty (THA/TKA) provide immediate and comprehensible information. However, they have limited reliability as satisfaction as a concept is influenced by factors unrelated to surgery. The aim of this retrospective study was to evaluate variation in pain, function and joint awareness relative to the patients' satisfaction response following THA/TKA. METHODS: We analysed absolute and improvement scores on the Oxford Knee or Hip score (OKS or OHS) and the Forgotten Joint Score-12 (FJS-12) across satisfaction groups. Patient-reported outcome measures were assessed prior to surgery and at 12-month follow-up. Postoperative satisfaction was assessed using a 5-point Likert scale single-item question. RESULTS: We analysed data from 434 TKA patients (mean age 70.4 ± 9.2 years; 54.8% female) and 247 THA patients (mean age 67.3 ± 11.8 years; 57.5% female). Satisfied or very satisfied patients showed higher absolute scores and better improvement in function, pain and joint awareness at 12 months (both, p < 0.001). 13.4% of (very) satisfied THA patients scored equally or worse on the FJS-12 than before surgery. On the OHS, this percentage was 2.8%. In TKAs, these percentages were 7.0% on the FJS-12 and 3.2% on the OKS. CONCLUSIONS: While higher satisfaction is associated with better patient-reported outcomes and stronger postoperative improvement, a certain percentage of patients score poorly while reporting a high satisfaction. Our results highlight the difficulty in interpreting the meaning of a single satisfaction question, as this provides limited information on patients' treatment outcome and may be biased by factors unrelated to the intervention.

Patient-reported outcome metrics following total knee arthroplasty are influenced differently by patients' body mass index.

PURPOSE: This study investigated the impact of body mass index (BMI) on improvement in patient outcomes (pain, function, joint awareness, general health and satisfaction) following total knee arthroplasty (TKA). METHODS: Data were obtained for primary TKAs performed at a single centre over a 12-month period. Data were collected pre-operatively and 12-month postoperatively with the Oxford Knee Score (OKS) measuring pain and function, the EQ-5D-3L measuring general health status, the Forgotten Joint Score-12 (FJS-12) measuring joint awareness and a single question on treatment satisfaction. Change in scores following surgery was compared across the BMI categories identified by the World Health Organization (< 25.0, 25.0-29.9, 30.0-34.9, 35.0-39.9 and ≥ 40.0). Differences in postoperative improvement between the BMI groups were analysed with an overall Kruskal-Wallis test, with post hoc pairwise comparisons between BMI groups with Mann-Whitney tests. RESULTS: Of 402 patients [mean age 70.7 (SD 9.2); 55.2% women] 15.7% were normal weight (BMI < 25.0), 33.1% were overweight (BMI 25.0-29.9), 28.2% had class I obesity (BMI 30.0-34.9), 16.2% had class II obesity (BMI 35.0-39.9), and 7.0% had class III obesity (BMI ≥ 40.0). Postoperative change in OKS (n.s.) and EQ-5D-3L (n.s.) was not associated with BMI. Higher BMI group was associated with less improvement in FJS-12 scores (p = 0.010), reflecting a greater awareness of the operated joint during activity in the most obese patients. Treatment satisfaction was associated with BMI category (p = 0.029), with obese patients reporting less satisfaction. CONCLUSIONS: In TKA patients, outcome parameters are influenced differently by BMI. Our study showed a negative impact of BMI on postoperative improvement in joint awareness and satisfaction scores, but there was no influence on pain, function or general health scores. This information may be useful in terms of setting expectations expectation in obese patients planning to undergo TKA. LEVEL OF EVIDENCE: Level 1.

What makes patients aware of their artificial knee joint?

BACKGROUND: Joint awareness was recently introduced as a new concept for outcome assessment after total knee arthroplasty (TKA). Findings from qualitative and psychometric studies suggest that joint awareness is a distinct concept especially relevant to patients with good surgical outcome and patients at late follow-up time points. The aim of this study was to improve the understanding of the concept of joint awareness by identifying situations in which patients are aware of their artificial knee joint and to investigate what bodily sensations and psychological factors raise a patient's awareness of her/his knee. In addition, we evaluated the relative importance of patient-reported outcome parameters that are commonly assessed in orthopaedics. METHODS: Qualitative interviews were conducted with patients being at least 12 months after TKA. The interviews focused on when, where and for what reasons patients were aware of their artificial knee joint. To evaluate the relative importance of 'joint awareness' after TKA among nine commonly assessed outcome parameters (e.g. pain or stiffness), we collected importance ratings ('0' indicating no importance at all and '10' indicating high importance). RESULTS: We conducted interviews with 40 TKA patients (mean age 69.0 years; 65.0% female). Joint awareness was found to be frequently triggered by kneeling on the floor (30%), climbing stairs (25%), and starting up after resting (25%). Patients reported joint awareness to be related to activities of daily living (68%), specific movements (60%), or meteoropathy (18%). Sensations causing joint awareness included pain (45%) or stiffness (15%). Psychological factors raising a patient's awareness of his/her knee comprised for example feelings of insecurity (15%), and fears related to revision surgeries, inflammations or recurring pain (8%). Patients' importance ratings of outcome parameters were generally high and did not allow differentiating clearly among them. CONCLUSIONS: We have identified a wide range of situations, activities, movements and psychological factors contributing to patients' awareness of their artificial knee joints. This improves the understanding of the concept of joint awareness and of a patient's perception of his/her artificial knee joint. The diversity of sensations and factors raising patient's awareness of their joint encourages taking a broader perspective on outcome after TKA.

Validation of the English language Forgotten Joint Score-12 as an outcome measure for total hip and knee arthroplasty in a British population.

AIMS: To validate the English language Forgotten Joint Score-12 (FJS-12) as a tool to evaluate the outcome of hip and knee arthroplasty in a United Kingdom population. PATIENTS AND METHODS: All patients undergoing surgery between January and August 2014 were eligible for inclusion. Prospective data were collected from 205 patients undergoing total hip arthroplasty (THA) and 231 patients undergoing total knee arthroplasty (TKA). Outcomes were assessed with the FJS-12 and the Oxford Hip and Knee Scores (OHS, OKS) pre-operatively, then at six and 12 months post-operatively. Internal consistency, convergent validity, effect size, relative validity and ceiling effects were determined. RESULTS: Data for the TKA and THA patients showed high internal consistency for the FJS-12 (Cronbach α = 0.97 in TKAs, 0.98 in THAs). Convergent validity with the Oxford Scores was high (r = 0.85 in TKAs, r = 0.79 for THAs). From six to 12 months, the change was higher for the FJS-12 than for the OHS in THA patients (effect size d = 0.21 versus -0.03). Ceiling effects at one-year follow-up were low for the FJS-12 with just 3.9% (TKA) and 8.8% (THA) of patients achieving the best possible score. CONCLUSION: The FJS-12 has strong measurement properties in terms of validity, internal consistency and sensitivity to change in TKA and THA patients. Low ceiling effects and good relative validity allow the monitoring of longer term outcomes, particularly in well-performing groups after total joint arthroplasty. Cite this article: Bone Joint J 2017;99-B:218-24.

Clinical outcome of increased flexion gap after total knee arthroplasty. Can controlled gap imbalance improve knee flexion?

PURPOSE: Increased range of motion (ROM) while maintaining joint stability is the goal of modern total knee arthroplasty (TKA). A biomechanical study has shown that small increases in flexion gap result in decreased tibiofemoral force beyond 90° flexion. The purpose of this paper was to investigate clinical implications of controlled increased flexion gap. METHODS: Four hundred and four TKAs were allocated into one of two groups and analysed retrospectively. In the first group (n = 352), flexion gap exceeded extension gap by 2.5 mm, while in the second group (n = 52) flexion gap was equal to the extension gap. The procedures were performed from 2008 to 2012. The patients were reviewed 12 months postoperatively. Objective clinical results were assessed for ROM, mediolateral and sagittal stability. Patient-reported outcome measures were the WOMAC score and the Forgotten Joint Score (FJS-12). RESULTS: After categorizing postoperative flexion into three groups (poor < 90°, satisfactory 91°-119°, good ≥ 120°) significantly more patients in group 1 achieved satisfactory or good ROM (p = 0.006). Group 1 also showed a significantly higher mean FJS-12 (group 1: 73, group 2: 61, p = 0.02). The mean WOMAC score was 11 in the first and 14 in the second group (n.s.). Increase in flexion gap did not influence knee stability. CONCLUSIONS: The clinical relevance of this study is that a controlled flexion gap increase of 2.5 mm may have a positive effect on postoperative flexion and patient satisfaction after TKA. Neither knee stability in the coronal and sagittal planes nor complications were influenced by a controlled increase in flexion gap. LEVEL OF EVIDENCE: III.

Responsiveness and ceiling effects of the Forgotten Joint Score-12 following total hip arthroplasty.

OBJECTIVES: To assess the responsiveness and ceiling/floor effects of the Forgotten Joint Score -12 and to compare these with that of the more widely used Oxford Hip Score (OHS) in patients six and 12 months after primary total hip arthroplasty. METHODS: We prospectively collected data at six and 12 months following total hip arthroplasty from 193 patients undergoing surgery at a single centre. Ceiling effects are outlined with frequencies for patients obtaining the lowest or highest possible score. Change over time from six months to 12 months post-surgery is reported as effect size (Cohen's d). RESULTS: The mean OHS improved from 40.3 (sd 7.9) at six months to 41.9 (sd 7.2) at 12 months. The mean FJS-12 improved from 56.8 (sd 30.1) at six months to 62.1 (sd 29.0) at 12 months. At six months, 15.5% of patients reached the best possible score (48 points) on the OHS and 8.3% obtained the best score (100 points) on the FJS-12. At 12 months, this percentage increased to 20.8% for the OHS and to 10.4% for the FJS-12. In terms of the effect size (Cohen's d), the change was d = 0.10 for the OHS and d = 0.17 for the FJS-12. CONCLUSIONS: The FJS-12 is more responsive to change between six and 12 months following total hip arthroplasty than is the OHS, with the measured ceiling effect for the OHS twice that of the FJS-12. The difference in effect size of change results in substantial differences in required sample size if aiming to detect change between these two time points. This has important implications for powering clinical trials with patient-reported measures as the primary outcome.Cite this article: Dr D. F. Hamilton. Responsiveness and ceiling effects of the Forgotten Joint Score-12 following total hip arthroplasty. Bone Joint Res 2016;5:87-91. DOI: 10.1302/2046-3758.53.2000480.

Making the Oxford Hip and Knee Scores meaningful at the patient level through normative scoring and registry data.

OBJECTIVES: The Oxford Hip and Knee Scores (OHS, OKS) have been demonstrated to vary according to age and gender, making it difficult to compare results in cohorts with different demographics. The aim of this paper was to calculate reference values for different patient groups and highlight the concept of normative reference data to contextualise an individual's outcome. METHODS: We accessed prospectively collected OHS and OKS data for patients undergoing lower limb joint arthroplasty at a single orthopaedic teaching hospital during a five-year period. T-scores were calculated based on the OHS and OKS distributions. RESULTS: Data were obtained from 3203 total hip arthroplasty (THA) patients and 2742 total knee arthroplasty (TKA) patients. The mean age of the patient was 68.0 years (sd 11.3, 58.4% women) in the THA group and in 70.2 (sd 9.4; 57.5% women) in the TKA group. T-scores were calculated for age and gender subgroups by operation. Different T-score thresholds are seen at different time points pre and post surgery. Values are further stratified by operation (THA/TKA) age and gender. CONCLUSIONS: Normative data interpretation requires a fundamental shift in the thinking as to the use of the Oxford Scores. Instead of reporting actual score points, the patient is rated by their relative position within the group of all patients undergoing the same procedure. It is proposed that this form of transformation is beneficial (a) for more appropriately comparing different patient cohorts and (b) informing an individual patient how they are progressing compared with others of their age and gender. Cite this article: Bone Joint Res 2015;4:137-144.

Patient-reported outcome assessment after total joint replacement: comparison of questionnaire completion times on paper and tablet computer.

INTRODUCTION: Patient-reported outcome (PRO) assessment is becoming increasingly important after joint replacement surgery. However, PRO data collection, questionnaire handling, and data processing are time consuming and costly process. The aim of our study was to evaluate the efficiency of PRO assessment using tablet computers compared with traditional paper questionnaires in a total hip or knee arthroplasty (THR or TKR) population. MATERIALS AND METHODS: We recruited 100 patients from outpatient clinics attending for routine follow-up 2 months, 1 year, or 5 years after THR or TKR. Fifty patients completed the Western Ontario and McMaster Universities (WOMAC) osteoarthritis score and Forgotten Joint Score-12 (FJS-12) questionnaires on paper, and 50 patients completed these on a tablet computer. Questionnaire completion was timed for each PRO assessment and for manual data entry of the paper questionnaires into the database. The t test, Mann-Whitney U test, Fisher's exact test, and Wilcoxon test were used for statistical analysis. RESULTS: The mean age of the patients was 67.0 years (standard deviation 10.3 years), with no significant difference between the two groups. Median time for WOMAC questionnaire completion (including data entry for the paper questionnaires) was 197 s for the paper version and 117 s for the tablet version (p < 0.001). Median times for completion of FJS-12 were comparable for paper and tablet versions (32 vs. 37 s). We did not find a significant correlation between age and time for questionnaire completion. CONCLUSION: Electronic PRO data collection can substantially decrease time, logistics, and effort associated with questionnaire completion in daily clinical practice. It is also acceptable for use in an older arthroplasty population.

Comparative responsiveness of outcome measures for total knee arthroplasty.

OBJECTIVE: The aim of this study was to compare the responsiveness of various patient-reported outcome measures (PROMs) and clinician-reported outcomes following total knee arthroplasty (TKA) over a 2-year period. METHODS: Data were collected in a prospective cohort study of primary TKA. Patients who had completed Forgotten Joint Score-12 (FJS-12), Western Ontario and McMaster Universities (WOMAC) osteoarthritis (OA) index, EQ-5D, Knee Society Score and range of movement (ROM) assessment were included. Five time points were assessed: pre-operative, 2 months, 6 months, 1 year and 2 years post-operative. RESULTS: Data from 98 TKAs were available for analysis. Largest effect sizes (ES) for change from pre-operative to 2-month follow-up were observed for the Knee Society Score (KSS) Knee score (1.70) and WOMAC Total (-1.50). For the period from 6 months to 1 year the largest ES for change were shown by the FJS-12 (0.99) and the KSS Function Score (0.88). The EQ-5D showed the strongest ceiling effect at 1-year follow-up with 84.4% of patients scoring the maximum score. ES for the time from 1- to 2-year follow-up were largest for the FJS-12 (0.50). All other outcome measures showed ES equal or below 0.30. CONCLUSION: Outcome measures differ considerably in responsiveness, especially beyond one year post-operatively. Joint-specific outcome measures are more responsive than clinician-reported or generic health outcome tools. The FJS-12 was the most responsive of the tools assessed; suggesting that joint awareness may be a more discerning measure of patient outcome than traditional PROMs.

Clinical outcome using a ligament referencing technique in CAS versus conventional technique.

PURPOSE: Computer-assisted surgery (CAS) for total knee arthroplasty (TKA) has become increasingly common over the last decade. There are several reports including meta-analyses that show improved alignment, but the clinical results do not differ. Most of these studies have used a bone referencing technique to size and position the prosthesis. The question arises whether CAS has a more pronounced effect on strict ligamentous referencing TKAs. METHODS: We performed a prospective cohort study comparing clinical outcome of navigated TKA (43 patients) with that of conventional TKA (122 patients). Patients were assessed preoperatively, and 2 and 12 months postoperatively by an independent study nurse using validated patient-reported outcome tools as well as clinical examination. RESULTS: At 2 months, there was no difference between the two groups. However, after 12 months, CAS was associated with significantly less pain and stiffness, both at rest and during activities of daily living, as well as greater overall patient satisfaction. CONCLUSION: The present study demonstrated that computer-navigated TKA significantly improves patient outcome scores such as WOMAC score (P=0.002) and Knee Society score (P=0.040) 1 year after surgery in using a ligament referencing technique. Furthermore, 91% were extremely or very satisfied in the CAS TKA group versus 70% after conventional TKA (P=0.007).

Tunnel placement in anterior cruciate ligament (ACL) reconstruction: quality control in a teaching hospital.

Correct placement of the femoral and tibial bone tunnels is decisive for a successful anterior cruciate ligament (ACL) reconstruction. Our method of tunnel placement was evaluated as part of quality control at a teaching hospital. The emphasis was placed mainly on investigating the influence of surgical experience on tunnel placement, and the effect of tunnel position on the clinical outcome. Seventeen surgeons with different levels of experience (between 0 and >150 ACL reconstructions) performed endoscopic ACL repair in uniform technique from August 2000 to August 2003 on 50 patients (18 women, 32 men, age range 18-43 years). The patients were available to clinical and radiological follow-up after an average of 19 months. The clinical outcome was classified according to the International Knee Documentation Committee (IKDC) standard evaluation form. The femoral tunnel was evaluated according to the quadrant method of Bernard and Hertel; the position of the tibial bone tunnel was assessed according to the criteria of Stäubli and Rauschnig. The IKDC score revealed 47 (94%) patients with a normal (A) or nearly normal (B) knee joint at follow-up. According to the quadrant method, the femoral canal was situated on average at 29% in the saggital plane. The tibial tunnel was situated on average at 43% of the a.p. diameter of the tibial condyle. Statistical analysis of our data showed no significant correlation between tunnel placement and surgical expertise. However, a highly significant correlation was found (alpha<0.01) between the femoral position of the tunnel in the sagittal plane and the IKDC score. The more anterior the femoral canal, the poorer the IKDC score. The method of tunnel placement in ACL reconstruction being investigated here only showed slight dependence on surgical experience, whereby good short-term clinical outcomes were achieved. Therefore, the method is suitable for application at a teaching hospital. A far too anterior femoral tunnel placement will probably lead to a decline in the clinical result.