High patient satisfaction with Customized Total Knee Arthroplasty at five year follow-up.

PURPOSE: Despite numerous studies demonstrating promising short-term outcomes of Total Knee Arthroplasty (TKA) with Customized Individually Made (CIM) implants, there is a significant lack of data on their mid-term effectiveness. Given the increasing number of TKAs performed annually, the rising demand for CIM implants, and the associated burden of revision surgeries, understanding the mid-term performance of CIM implants is crucial. Therefore, this study aims to report on the mid-term (minimum 5 years) outcomes of TKA using a CIM implant. METHODS: This retrospective cohort study included a consecutive series of 116 patients who received the ConforMIS® iTotal CR implant between 2015 and 2018. Inclusion criteria were end-stage knee osteoarthritis with coronal deformities below 10° and absence of ligamentous instability. Exclusion criteria included simultaneous bilateral TKA. Patients were followed up at a minimum of five years post-surgery. They completed a questionnaire reporting on satisfaction, pain levels using the Visual Analogue Scale (VAS), current weight, the Oxford Knee Score (OKS), and the Forgotten Joint Score for the knee (FJS-knee). Statistical analysis included descriptive statistics for demographic and clinical variables, and outcomes were reported as means with ranges. RESULTS: The mean follow-up duration was 5.9 ± 0.8 years (range 5-7.4 years). 90% of patients stated they would undergo the same operation again, and 93% were either satisfied or very satisfied. The mean VAS for pain at rest was 2 ± 1.5 (range 0-6) and during exercise was 3 ± 2 (range 0-8). 58 patients (53%) managed to lose weight. The mean OKS was 41 ± 9 points (range 15-48), and the mean FJS-knee was 67 ± 23 points (range 4-100). No severe complications occurred. CONCLUSION: CIM TKA using the ConforMIS® iTotal CR implant can achieve excellent results with 93% of patients being satisfied or very satisfied at mid-term follow-up of five years. Prospective, randomized, and patient-blinded trials comparing off-the-shelf (OTS) TKAs with CIM implants are necessary to evaluate whether these implants are superior or not.

Optimism and pessimism are antithetically associated with post-operative knee function in patients' undergoing total knee arthroplasty.

PURPOSE: Personality traits, such as dispositional optimism and pessimism, have impact on a variety of health-related problems. Influence on outcome in total knee arthroplasty (TKA) could only be shown for other personality trait concepts, but not for dispositional optimism/pessimism. This study aims to examine the association of dispositional optimism/pessimism with pre-operative joint function and post-operative outcome in TKA. METHODS: Data were acquired in a multicentre, cross-sectoral, prospective study (the PROMISE Trial). Patients were followed for 12 months post-operatively. Dispositional optimism/pessimism was measured pre-operatively via the revised Life Orientation Test (LOT-R), pre- and post-operative function was measured via the 12 Item Knee-osteoarthritis outcome Scores (KOOS-12). Log-linear regression models considering known confounders and t-test were carried out to show the association of LOT-R scores with pre- and post-operative KOOS-12 scores. RESULTS: 740 patients were analyzed. Optimistic LOT-R was significantly positively associated to the mean scores of KOOS-12 pre- and post-operative, while pessimistic LOT-R was significantly associated negatively (pre-operative: optimistic p = 0.001, pessimistic p = 0.001; post-operative optimistic: 3M p = 0.001, 6M p = 0.001, 12M p = 0.001; post-operative pessimistic: 3M p = 0.01, 6M p = 0.004, 12M p = 0.001). CONCLUSION: Optimism was positively associated with pre-operative joint function and, more importantly, post-operative functional outcome in TKA, while pessimism was associated with the opposite. Assessing patients' general personality traits prior to surgery to identify pessimistic patients, hence being at risk for poor outcome in TKA, should be considered to react to the patients' special needs and possible pessimistic expectations, i.e., through a cognitive-behavioral intervention, to potentially increase optimism and hereby post-operative outcome in TKA. LEVEL OF EVIDENCE: Prognostic Level III.

Simultaneous bilateral TKA in the context of fast track surgery - Do patients meet discharge criteria as anticipated?

BACKGROUND: The efficacy and safety of enhanced recovery after surgery (ERAS) protocols for patients undergoing total knee arthroplasty (TKA) have been generally proven. Previous studies investigating patients undergoing simultaneous bilateral TKA (SBTKA) focused on complications, mortality, and pain and did not examine patients' functional limitations. Therefore, the aim of this study was to investigate to what extent patients undergoing SBTKA are able to meet functional discharge criteria originally designed for their counterparts undergoing unilateral TKA (UTKA) in an ERAS setting. MATERIALS AND METHODS: All patients who received primary SBTKA between June 2015 and December 2018 were included in this retrospective analysis. For comparison, UTKA patients were matched 1:1 to SBTKA patients using Propensity Score Matching based on age, gender, and BMI. The times to achieving the rehabilitation checkpoints of walking 150 m, walking a flight of stairs, and 90° knee flexion were evaluated. RESULTS: 63 (SBTKA group) and 64 (UTKA group) patients were included. Due to the Propensity-Score-Matching there were no differences regarding age, gender, and BMI. The mean length of stay (LOS) was 9.1 days in the SBTKA and 7.6 days in the UTKA group (p = 0.003). On average, it took SBTKA patients 5.4 days to achieve an uninterrupted walking distance of at least 150 m, while it took UTKA patients 4.1 days (p < 0.001). Mean time to walking a flight of stairs was 6.3 days for SBTKA patients and 4.7 days for UTKA patients (p < 0.001). 90° flexion was achieved after 4.1 days by SBTKA patients and 3.5 days by UTKA patients (p = 0.241). CONCLUSION: The vast majority of SBTKA patients were able to achieve functional discharge criteria within their inpatient stay when allowed about 30% extra time. Therefore, functional discharge criteria in ERAS protocols designed for UTKA can be considered appropriate for SBTKA patients. LEVEL OF EVIDENCE: Therapeutic Level III.

[Discharge readiness versus discharge-Results of the PROMISE study]. / Entlassbarkeit versus Entlassung ­ Ergebnisse der PROMISE-Studie.

BACKGROUND: In the context of optimized treatment processes for knee and hip replacements, lengths of stay are given for Germany that clearly exceed the internationally published ones. In this context, the present analysis of data from the PROMISE study deals with the relationship between discharge readiness and discharge. METHODS: In the PROMISE study, a jointly developed, optimized standard of care was established in three hospitals of different levels of care and realized for a typical, largely unselected cohort of patients. Among others, data were collected on achievement of discharge criteria (DC) and actual discharge. Univariate comparisons were performed by chi-square tests or the Mann-Whitney­U tests. RESULTS: A total of 1782 patients were included, of whom a mean of 85.3% achieved all previously defined DCs at a mean of 2.4 (median 2) days postoperatively. Discharge for this group occurred after a mean of 5.4 (median 5) days. 14.7% of the participants did not achieve at least one DC. This group was discharged after a mean of 6.5 (median 6) days. Significant differences in outcomes were observed for different subgroups. CONCLUSION: The so-called DCs are used as relative criteria. Achievement generally does not result in timely discharge. If this were to happen, internationally established lengths of stay would also be a reality in Germany. What actually determines discharge from inpatient treatment remains open. A variety of medical, organizational, structural and financial factors could be of importance.

Comparison of Postoperative Coronal Leg Alignment in Customized Individually Made and Conventional Total Knee Arthroplasty.

Neutral coronal leg alignment is known to be important for postoperative outcome in total knee arthroplasty (TKA). Customized individually made implants (CIM) instrumented with patient-specific cutting guides are an innovation aiming to increase the precision and reliability of implant positioning and reconstruction of leg alignment. We aimed to compare reconstruction of the hip-knee-ankle angle (HKA) of the novel CIM system iTotal™ CR G2 (ConforMIS Inc.) to a matched cohort of the off-the-shelf (OTS) knee replacement system Vanguard™ CR (Zimmer Biomet). Retrospective analysis of postoperative coronal full-leg weight-bearing radiographs of 562 TKA (283 CIM TKA, 279 OTS TKA) was conducted. Via a medical planning software, HKA and rotation of the leg were measured in postoperative radiographs. HKA was then adjusted for rotational error, and 180° ± 3° varus/valgus was defined as the target zone HKA. Corrected postoperative HKA in the CIM group was 179.0° ± 2.8° and 179.2° ± 3.1° in the OTS group (p = 0.34). The rate of outliers, outside of the ±3° target zone, was equal in both groups (32.9%). Our analysis showed that TKA using patient-specific cutting guides and implants and OTS TKA implanted with conventional instrumentation resulted in equally satisfying restoration of the coronal leg alignment with less scattering in the CIM group.