Better Flexion but Unaffected Satisfaction After Treatment With Posterior Stabilized Versus Cruciate Retaining Total Knee Arthroplasty - 2-year Results of a Prospective, Randomized Trial.

BACKGROUND: Both the cruciate-retaining (CR) and posterior-stabilized (PS) implant systems are commonplace in modern total knee arthroplasty (TKA) practice. However, there is controversy regarding functional outcomes and survivorship. The aim of the underlying study was to evaluate differences between CR and PS TKA regarding knee function, patient-reported outcome measures (PROMs) as well as complication rates. METHODS: 140 patients with knee osteoarthritis scheduled for an unconstrained TKA were enrolled in a prospective, randomized study. Patients received either a CR or PS implant. Range of motion and PROMs (Oxford Knee Score, Knee Society Score, European Quality of Life 5 Dimensions 3 Level, University of California Los Angeles Activity scale and subjective satisfaction) were assessed prior to, 3 months, 1 and 2 years after surgery. RESULTS: We found minor differences between treatment groups regarding demographic factors. Within the PS group duration of surgery was longer (mean PS 81.4 min vs CR 76.0 min, P = .006). We observed better flexion (median PS 120.0° vs CR 115°, P = .017) and an overall better range of motion (median PS 120.0° vs CR 115.0°, P = .008) for the PS group. PROMs did not differ between groups. At 2-year follow-up there were no revisions in either cohort. Five patients needed reoperations. Three patients needed manipulation under anesthesia, 2 in the CR and one in the PS group. CONCLUSION: While PS TKA achieved a better flexion capability, PROMs were similar in CR and PS TKA. The CR implant design continues to be a reliable option for patients with an intact posterior cruciate ligament.

The Effect of Waiting for a Primary Total Hip Arthroplasty on the Overall Hip Function and Quality of Life.

BACKGROUND: The primary aim was to determine whether time spent awaiting primary total hip arthroplasty (THA) affects patient-reported outcome measures (PROMs) using the Oxford Hip score, Harris Hip Score, and visual analogue scale (VAS) pain. The secondary aim was to assess whether patients have worsening HRQoL, while awaiting THA using the European Quality of Life Five Dimension (EQ-5D) index and EQ-5D health VAS. METHODS: This was a single center cross-sectional study of 190 patients awaiting THA. Patients were divided into waiting "more than 6 months" and "less than 6 months." Baseline and current scores were compared. Multivariate regression analyses were performed to identify predictors of PROM change. RESULTS: No significant intergroup differences were observed for change in preoperative Oxford Hip score, Harris Hip Score, and VAS pain from index consultation to time of study. The EQ-5D index and EQ-5D health VAS decreased significantly further in patients waiting more than 6 months (P = .043, P = .004). Time awaiting THA was significantly associated with a decrease in EQ-5D index and EQ-5D health VAS in multivariate regression (P = .013, P < .001). CONCLUSIONS: Waiting more than 6 months is not associated with a decrease in hip-specific PROMs and longer waiting times are not associated with changes in hip-specific PROMs. Waiting time was associated with a decrease in health-related quality of life and patients waiting more than 6 months had significantly higher decreases in EQ-5D scores. This suggests that living longer with hip osteoarthritis leads to a decrease in QoL, not necessarily through perceived osteoarthritis progression. LEVEL OF EVIDENCE: Level III cross-sectional study.

No difference in patient reported outcome and inflammatory response after coated and uncoated total knee arthroplasty - a randomized controlled study.

BACKGROUND: Allergies against implant materials are still not fully understood. Despite controversies about its relevance, some patients need treatment with hypoallergenic implants. This study compared coated and standard total knee arthroplasty (TKA) regarding inflammatory response and patient-reported outcome measures (PROMs). METHODS: 76 patients without self-reported allergies against implant materials were included in a RCT and received a coated or standard TKA of the same cemented posterior-stabilized knee system. 73 patients completed the 3-year follow-up. Two patients died and there was one revision surgery. Serum levels of cytokines with a possible role in implant allergy were measured in patient`s serum (IL-1beta, IL-5, IL-6, IL-8, IL-10, IFN γ, TNF α) prior to, one and three years after surgery. Furthermore, PROMs including knee function (Oxford Knee Score, Knee Society Score) and health-related quality of life (QoL, EuroQuol questionnaire) were assessed. Additionally, 8 patients with patch-test proven skin allergy against implant materials who received the coated implant were assessed similarly and compared to a matched-pair group receiving the same implant. RESULTS: There were no differences in function and QoL between the assessed groups at any follow-up. The majority of patients demonstrated no elevation of the measured blood cytokines. Cytokine patterns showed no differences between study groups at any follow-up. The allergy patients demonstrated slower functional improvement and minor differences in cytokine pattern. Yet these results were not significant. There were no differences in the matched-pair analysis. CONCLUSION: We observed no relevant increase in serum cytokine levels in any group. The inflammatory response measured seems limited, even in allergy patients. Furthermore, there were no differences between coated and standard TKA in non-allergy patients in the 3-year Follow-Up period. TRIAL REGISTRATION: The study protocol was registered in the US National Institutes of Health's database ( http://www. CLINICALTRIALS: gov ) registry under NCT03424174 on 03/17/2016.

Fulfilment of patients' mandatory expectations are crucial for satisfaction: a study amongst 352 patients after total knee arthroplasty (TKA).

PURPOSE: Patient satisfaction with the results of their total knee arthroplasty (TKA) is one of the primary goals of this elective procedure. Furthermore, the association between the fulfilment of patients' expectations and their satisfaction is well known. The aim of this study was to identify the key expectations of patients awaiting a TKA, evaluate their fulfilment, and compare the outcomes between very and not fully satisfied patients. METHODS: A prospective cohort study of patients with knee OA scheduled for primary TKA was performed. Pre- and one-year postoperatively patient-reported outcome measures (PROMs) were assessed. Expectations and their fulfilment were evaluated via a questionnaire encompassing 31 expectations. Preoperatively, expectations were indicated as mandatory, desirable and not important. Postoperatively, fulfilment was rated as exceeded, fulfilled, partially or not fulfilled, and not applicable. Satisfaction with the results of TKA was measured with a numeric rating scale (NRS) of 0-10. Discrimination between not fully satisfied and very satisfied patients was set at ≥ 8, as has been proposed recently. To identify independent predictors of this discrimination, a multivariate logistic regression analysis was performed. RESULTS: Complete data sets of 352 patients were analysed. A set of 17 key expectations was identified. Relief of knee pain was fulfilled the most, and improvement of physical function was fulfilled the least. When asked about overall fulfilled expectations, 40% of patients rated them as exceeded, 34% as fulfilled and 26% as less fulfilled than expected. Not fully satisfied patients showed significantly lower PROMs pre- and postoperatively and less fulfilled key expectations. Higher numbers of exceeded and fulfilled mandatory expectations, higher overall fulfilment and better range of motion (ROM) were significant predictors for satisfaction ≥ 8. CONCLUSION: Patients' expectations of TKA outcomes were high with equal emphasis on knee-related and general health-related aspects. Their fulfilment was positively associated with satisfaction. Surgeons should ask patients about mandatory expectations for successful TKA and counsel them about the likelihood of their fulfilment to avoid unrealistic expectations. LEVEL OF EVIDENCE: II.

Increased inflammatory response is associated with less favorable functional results 5 years after total knee arthroplasty.

PURPOSE: Allergy against implant materials is discussed controversially and still not fully understood. Despite these controversies, a relevant number of patients receive hypoallergenic knee implants. The aim of this study was to compare a new coating system with the standard implant in total knee arthroplasty (TKA). Additionally, the influence of proinflammatory cytokines on patient-reported outcome measures (PROMs) was investigated. METHODS: 120 patients without known metal allergy and without previous metal implants were included. The patients were randomized to receive a coated or standard TKA of the same knee system. 105 patients completed the 5 year follow-up. Patient-reported outcome measures (PROMs) including knee function (Oxford Knee Score, OKS), quality of life (SF36) and UCLA activity scale were assessed. Additionally, several cytokines with a possible role in implant allergy were measured in patient`s serum (IL-1beta, IL-5, IL-6, IL-8, IL-10, IP-10, IFN γ, TNF α). Group comparison was performed using Mann-Whitney U test for continuous values and chi-square test for categorical values. RESULTS: There were no differences in PROMs between both groups at any follow-up. The majority of patients demonstrated no elevation of the measured blood cytokines. The blood cytokine pattern after 5 years demonstrated no differences between study groups. There was a significant association between elevated IL-8 values and worse results in the overall OKS (p = 0.041), the OKS function component (p = 0.004), the UCLA activity scale (p = 0.007) and the physical component of SF36 (p = 0.001). CONCLUSION: There were no problems with the new coating during mid-term follow-up and no differences in PROMs between coated and standard TKA. Patients with an increased inflammatory response demonstrated worse functional results, regardless of the implant. LEVEL OF EVIDENCE: I. CLINICAL TRIAL REGISTRATION: The study protocol was registered in the US National Institutes of Health's database ( http://www. CLINICALTRIALS: gov ) registry under NCT00862511.

A Novel Multilayer-Coating for Total Knee Arthroplasty Implants is Safe - 10-Year Results From a Randomized-Controlled Trial.

BACKGROUND: This randomized-controlled trial was initiated to compare a new multilayer hypoallergenic coating system with the standard implant in total knee arthroplasty (TKA) in terms of serum metal ion levels, patient-reported outcomes (PROs), and implant survival. METHODS: A total of 120 patients were randomized to receive a coated or standard TKA of the same knee system. Serum metal ion levels (ie, cobalt, chromium, molybdenum, and nickel) as well as knee function (Oxford Knee Score, OKS), quality of life (SF-36), and physical activity (UCLA activity scale) were assessed before surgery and until the 10 year follow-up. A total of 24 patients died and there was one revision in each group. This resulted in 85 patients who completed follow-up. RESULTS: Both groups demonstrated equally good improvement in PROs after surgery and constant score values thereafter. The majority of patients had metal ion serum levels below detection limit. Only cobalt levels demonstrated a slight increase in the standard group at 5- and 10-year follow-up. However, all patients displayed values below 3 µg/L. The cumulative 10-year survival was 98% in both groups. CONCLUSION: There were no problems with the new coating system. No relevant increase in metal ion serum levels were measured. A slight increase in cobalt serum levels in the standard TKA was noted, thus not reaching critical values. The new coating system demonstrated equally good PROs as the standard TKA. Excellent implant survival was observed in both groups. LEVEL OF EVIDENCE: I.

Ultracongruent insert design is a safe alternative to posterior cruciate-substituting total knee arthroplasty: 5-year results of a randomized controlled trial.

PURPOSE: If substitution of the posterior cruciate ligament in total knee arthroplasty is necessary, there are two options available: posterior stabilized (PS) design with a post-cam mechanism or anterior-lipped ultracongruent (UC) inserts. UC inserts have the advantage that no femoral box is necessary and a standard femoral component can be used. The aim of this study was to compare the range of motion (ROM) and patient-reported outcome (PRO) after UC and PS fixed-bearing TKA. Better ROM in PS TKA and no difference in PRO between both designs was hypothesized. METHODS: A randomized controlled trial with 127 patients receiving a fixed-bearing UC or PS design of the same knee system was performed. Nine patients died and there were four revision surgeries. 107 patients completed the 5-year follow-up. Patient-reported outcome was assessed. Patellofemoral problems were evaluated using selected applicable questions of the Oxford Knee Score (getting up from a table, kneeling, climbing stairs). RESULTS: Surgical time was 10 min shorter in the UC group (p < 0.001). After 5 years, both groups demonstrated good knee function and health-related quality of life without significant differences between the groups. Both groups demonstrated a high satisfaction score and the majority of patients would undergo this surgery again. Patellofemoral problems were recognized more frequently in the PS group (p = 0.025). CONCLUSION: Both designs demonstrated similar good results after 5 years. Stabilization with an anterior-lipped UC insert can be considered a safe alternative to the well-established PS design if cruciate substitution is necessary.

Ask Patients What They Expect! A Survey Among Patients Awaiting Total Hip Arthroplasty in Germany.

BACKGROUND: Total hip arthroplasty (THA) is an elective surgery. Therefore, patient satisfaction with the results of surgery is paramount. The association between fulfillment of patients' expectations and satisfaction is well known. The aim of this study was to identify key expectations of patients with hip osteoarthritis awaiting THA. METHODS: A mixed-methods approach was used, consisting of two sequential parts. The questionnaire was developed based on literature review and focus group interviews. A nationwide survey was conducted in 21 orthopedic departments within Germany. RESULTS: Out of 691 obtained questionnaires, 636 were analyzed (mean age = 65.7 years (±11.3), 56.1% female). A majority of patients (≥75%) reported more than 20 complaints as 'present' due to hip osteoarthritis. A total of 9 key expectations were identified, which were reported by more than 75% of the patients as 'mandatory' for a successful THA. The identified key expectations were related to pain, range of motion, walking abilities, gait pattern, transitions, leisure and sports activities, awareness of the affected hip, satisfaction with health or life, and compensatory posture. A consistently high correlation was found between the complaints and the corresponding expectations. CONCLUSION: The expectations of patients have greatly expanded. In this study, a set of mandatory key expectations shared by the majority of patients was identified. The likelihood of fulfillment of key expectations should be assessed for weighing benefits and harms of available treatment options during the indication process. In addition, the results of this study might be used as a resource for shared decision-making.

Indication Criteria for Total Hip Arthroplasty in Patients with Hip Osteoarthritis-Recommendations from a German Consensus Initiative.

Background: Osteoarthritis of the hip (hip OA) is a leading cause of pain and disability in elderly people. If non-surgical therapies become ineffective, patients may consider total hip arthroplasty (THA). The biggest challenge in recommending a THA is identifying patients for whom the benefits of this procedure outweigh the potential risks. The aim of this initiative was to develop a clinical practice guideline with accompanying algorithm to guide consultations on THA, supported by a pocket-sized checklist. Methods: The initiative "Evidence- and consensus-based indication criteria for total hip replacement (EKIT-Hip)" used a stepwise approach, starting with an inauguration workshop, where a multidisciplinary German stakeholder panel from various scientific societies agreed on the working process. A Project Coordinating Group (PCG) was formed, and it performed a comprehensive systematic literature search of guidelines and systematic reviews related to the indication criteria for THA, as well as factors influencing outcomes. Based on best-available evidence, preliminary recommendations were formulated by the PCG and discussed with the stakeholder panel during a consensus meeting. In addition, the panel was asked to assess the feasibility of an extracted algorithm and to approve a final checklist. Results: In total, 31 recommendations were approved by 29 representatives of 23 societies. These were used to underpin an algorithm (EKIT-Algorithm), which indicates the minimum requirements for a THA (confirmed diagnosis of hip OA, present and documented individual burden of illness, ineffectiveness of non-surgical therapies, and absence of any contraindications). Once these criteria are fulfilled, further considerations should encompass the medical implications of modifiable risk factors and patients' individual treatment goals, as discussed during shared decision making. The subsequently developed checklist (EKIT-Checklist) lists relevant criteria for decision making. Conclusions: Adherence to the EKIT-Algorithm, conveniently accessed via the EKIT-Checklist, should improve the standardization of decision making leading to a recommendation for THA. By applying minimum requirements and patient-related risk factors, as well as considering patients' individual goals, it is possible to identify patients for whom the benefits of THA may exceed the potential risks.

Similar outcomes in computer-assisted and conventional total knee arthroplasty: ten-year results of a prospective randomized study.

BACKGROUND: Computer-assisted navigation (CAS) was developed to improve the surgical accuracy and precision. Many studies demonstrated better alignment in the coronal plane in CAS TKA compared to conventional technique. The influence on the functional outcome is still unclear. Only few studies report long-term results of CAS TKA. This study was initiated to investigate 10-year patient-reported outcome of CAS and conventional TKA. METHODS: From initially 80 patients of a randomized study of CAS and conventional TKA a total of 50 patients could be evaluated at the 10-year follow-up. The Knee Society Score and EuroQuol Questionnaire were assessed. For all patients a competing risk analysis for revision was performed. RESULTS: The patient-reported outcome measures demonstrated similar values for both groups. The 10-year risk for revision was 2.5% for conventional TKA and 7.5% for CAS TKA (p=0.237). CONCLUSIONS: There was no difference between CAS and conventional TKA with regard to patient-reported outcome and revision risk ten years after surgery. TRIAL REGISTRATION: This study was registered at clinicaltrials.gov on 11/30/2009, ID: NCT01022099 .

[Are the results of total knee arthroplasty after high tibial osteotomy worse?] / Sind die Ergebnisse von Knietotalendoprothesen nach Tibiakopfumstellungsosteotomie schlechter?

BACKGROUND: In some cases, total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is necessary. HTO can adversely affect anatomy and alignment resulting in more complicated and challenging TKA surgery. The aim of this study was to investigate whether patients having undergone HTO benefit from TKA to the same extent as patients with primary osteoarthritis of the knee. METHODS: A total of 44 patients after HTO and 1703 patients with primary osteoarthritis of the knee were identified in the local registry. To reduce confounders, a 1:1 propensity score matched-pair analysis (age, gender, BMI, comorbidities) was carried out in patients with a 5-year follow-up. This resulted in 35 matched pairs, which were compared for knee function, pain level, satisfaction and perioperative data (operative time, implant type, complications) and revisions. RESULTS: Patients having undergone HTO had no significant differences in knee function prior and 5 years after surgery but a significantly higher pain level. Despite the higher pain level before and after TKA, there was a similar satisfaction with the result of the surgery. The operative time for TKA was significantly longer after HTO and modular implants with stem and wedges were used significantly more often. The two cohorts did not differ with respect to complications within the first 3 months after surgery. The revision rate within 5 years was not increased in patients after HTO. CONCLUSION: Patients having undergone HTO achieved a similar knee function in comparison to patients with primary osteoarthritis of the knee after TKA. However, a higher pre- and postoperative pain level was recorded in patients following HTO. The surgical effort was significantly higher after HTO.

[Decision for total hip arthroplasty-the surgeons' view]. / Indikationsstellung zur Hüfttotalendoprothese ­ die ärztliche Perspektive.

BACKGROUND: The decision for total hip arthroplasty (THA) is based on pain, loss of function, radiological changes and failed conservative therapy. These criteria are rarely based on systematic research and have not been integrated in generally accepted treatment guidelines. Aim of our study was, therefore, to analyse which decision criteria German orthopaedic and trauma surgeons use in order to recommend THA for patients with hip osteoarthritis. MATERIALS AND METHODS: From 10/2019 to 07/2020 we conducted a nation-wide survey among 218 orthopaedic and trauma surgeons about their criteria for and against THA surgery, as well as their treatment objectives. RESULTS: 147 fully completed questionnaires were analysed. Pain (99%), limitation of movement (99%), as well as impairment of walking distance (97%), and the subjective burden (97%) were the most frequent criteria. 97% and 96% of surgeons consider prescription of analgesics and physical therapy, as well as a lack of their effectiveness, as criteria for THA. 87% see radiological changes grade Kellgren & Lawrence III as threshold. A recommendation against surgery is triggered by obesity (BMI ≥ 40 kg/m2) in 48% and by the presence of an active infection in 96%. CONCLUSIONS: Current surgeons' practice criteria of recommendations for THA in Germany seem to reflect widely nationally and internationally discussed recommendations. Particular attention is given to patient factors like pain, loss of function and subjective burden, as well as previous conservative treatment and contraindications, like poorly controlled diabetes or an active infection, whereas morbid obesity is not seen as contraindication by all surgeons.

Fulfillment of expectations influence patient satisfaction 5 years after total knee arthroplasty.

PURPOSE: Constant efforts have been made to improve prosthesis design in total knee arthroplasty (TKA), but a significant number of patients remain dissatisfied postoperatively. Besides poor improvement in pain or function, poor fulfillment of patients expectations were identified as contributing factors. Purpose of the study was to assess fulfillment of patients' expectations and satisfaction with TKA 5 years after surgery. METHODS: A total of 103 patients from a prospective randomised study of a high-flexion or standard TKA implant were investigated 5 years after surgery and patient-reported outcomes (PRO), fulfillment of expectations and satisfaction with the result of the surgery were obtained. RESULTS: There were no differences in PROs, fulfillment of expectations and satisfaction between both implant designs. In total, the patients had high expectations preoperatively, mainly related to pain relief and functional abilities. A total of 89.4% of these expectations were fulfilled. No re-interventions (p < 0.001) and male gender (p = 0.017) were the most important predictors of higher fulfillment of expectations. Satisfaction scored highly at 8.2 out of 10 and most patients (93.2%) would undergo the surgery again. Higher Knee Score (p = 0.012) and fulfillment of expectations (p = 0.002) were correlated with higher satisfaction. CONCLUSION: Five years after surgery fulfillment of expectations and satisfaction were high regardless of implant design and did significantly influence patient satisfaction. Surgeons should be aware of the importance of patients' expectations and their influence on satisfaction after TKA. Therefore, the probability of fulfillment should be discussed during shared decision making for TKA. LEVEL OF EVIDENCE: I.

Analysis of Total Knee Arthroplasty revision causes.

BACKGROUND: The number of revision Total Knee Arthroplasty (TKA) is rising in many countries. The aim of this study was the prospective assessment of the underlying causes leading to revision TKA in a tertiary care hospital and the comparison of those reasons with previously published data. METHODS: In this study patients who had revision TKA between 2010 and 2015 were prospectively included. Revision causes were categorized using all available information from patients' records including preoperative diagnostics, intraoperative findings as well as the results of the periprosthetic tissue analysis. According to previous studies patients were divided into early (up to 2 years) and late revision (more than 2 years). Additional also re-revisions after already performed revision TKA were included. RESULTS: We assessed 312 patients who underwent 402 revision TKA, 89.6% of them were referred to our center for revision surgery. In 289 patients (71.9%) this was the first revision surgery after primary TKA. Among the first revisions the majority was late revisions (73.7%). One hundred thirteen patients (28.1%) had already had one or more revision surgeries before. Overall, the most frequent reason for revision was infection (36.1%) followed by aseptic loosening (21.9%) and periprosthetic fracture (13.7%). CONCLUSIONS: In a specialized arthroplasty center periprosthetic joint infection (PJI) was the most common reason for revision and re-revision TKA. This is in contrast to population-based registry data and has consequences on costs as well as on success rates in such centers.

Similar outcome during short-term follow-up after coated and uncoated total knee arthroplasty: a randomized controlled study.

PURPOSE: Patients with known hypersensitivity to metals often require hypoallergenic TKA implants. Coating of a standard implant is a common solution, and although in vitro tests have demonstrated reduction of polyethylene wear for these coatings, it is still unknown whether these implants have any clinical benefit. This study was initiated to investigate metal ion concentrations, knee function and patient-reported outcome (PRO) after coated and uncoated TKA. METHODS: One hundred and twenty-two (122) patients were randomized to receive a coated or a standard TKA and, after exclusions, 59 patients were included in each group. Knee function and PRO were assessed with validated scores up to 3 years after surgery. Metal ion concentrations in blood samples were determined for chromium, cobalt, molybdenum and nickel, preoperatively and 1 year after surgery. RESULTS: Chromium concentrations in patient plasma increased from a median of 0.25 to 1.30 µg/l in the standard TKA group, and from 0.25 to 0.75 µg/l in the coated TKA group (p = 0.012). Thirteen patients (3 coated, 10 standard TKA) had chromium concentrations above 2 µg/l. The concentrations of cobalt, molybdenum and nickel did not change. Patient-reported outcome measures (PROM) demonstrated a substantial improvement after TKA, without any differences between the groups. CONCLUSION: The increase in chromium concentration in the standard group needs further investigation. If surgeons use coated implants, they can be confident that these implants perform as well as standard implants. LEVEL OF EVIDENCE: I.

No difference in range of motion between ultracongruent and posterior stabilized design in total knee arthroplasty: a randomized controlled trial.

PURPOSE: The use of an ultracongruent (UC) insert with a standard femoral component for substitution of the posterior cruciate ligament (PCL) is a bone-preserving and therefore interesting alternative to the established box and cam mechanism of posterior stabilized (PS) total knee arthroplasty (TKA). This study investigated range of motion (ROM), stability and patient-reported outcome (PRO) in UC and PS TKA. We hypothesized better knee flexion with the PS design but no difference in stability and PRO between UC and PS TKA. METHODS: A randomized controlled study was performed. One hundred and twenty-seven patients were included, 63 with an UC and 64 with a PS TKA (Columbus, Aesculap, Tuttlingen, Germany). Intraoperative stability and range of motion was measured with the use of a navigation system. Patients were assessed before surgery, 3 months and 1 year postoperatively. RESULTS: There was no difference in ROM between both groups, neither intraoperatively nor at follow-up. There was 5 mm less sagittal translation at 90° of knee flexion (p < 0.001) and more posterior femoral rollback during knee flexion in the PS TKA. Axial rotation between extension and knee flexion was reduced by both designs. UC TKA was 7 min faster (p = 0.001). At the one-year follow-up, the Knee Society Score was similar in both groups, the Oxford Knee Score demonstrated better results in the UC TKA group (p = 0.048). CONCLUSION: Increased intraoperative sagittal translation and reduced posterior femoral rollback during knee flexion of UC TKA seem to have no negative influence on short-term clinical outcome. Therefore, UC TKA seems to be a practical alternative to the established PS TKA for substitution of the PCL. This might be especially interesting for surgeons who do not always substitute the PCL. LEVEL OF EVIDENCE: I.

Patient activity after TKA depends on patient-specific parameters.

BACKGROUND: Most patients expect an improvement of walking ability and an increase in activity levels after TKA. Unfortunately, few studies report qualitative and quantitative activity improvements after TKA. QUESTIONS/PURPOSES: The aims of this study were (1) to evaluate quantity and quality of physical activity before and after TKA with an accelerometer, and to compare activity level with that of an age-matched control group without lower-extremity disorders. (2) Improvement in measured steps per day after TKA and the ability to meet physical activity guidelines were evaluated. (3) The influence of patient-specific and implant parameters were assessed. PATIENTS AND METHODS: An accelerometer was used to measure activity in 97 patients who were assessed before TKA and 1 year after TKA. The measurements included the total number of steps, moderate to vigorous activity defined as at least 100 steps per minute, and time spent lying, sitting/standing, or walking. We then calculated the proportion of patients who met the 10,000 steps per day guideline recommendation and determined factors that predicted failure to meet that goal. Thirty-nine age-matched control subjects without lower-extremity disorders were selected and underwent the same assessments using the accelerometer for comparison with patients 1 year after TKA. RESULTS: Measured steps per day improved from a mean of 5278 (SD, 2999) preoperatively to 6473 (SD, 3654) postoperatively (effect size, 1.23; 95% CI, 1.10-1.35; p < 0.001). Moderate to vigorous steps per day improved from a mean of 1150 (SD, 982) to 1935 (SD, 1728; p < 0.001). Times spent in lying, sitting, or standing position or during walking did not change after TKA. For all measured parameters, activity of the patients after TKA was considerably less than that of the age-matched control subjects, who walked a mean of 13,375 (SD, 4614) steps per day (p < 0.001), performed a mean of 6562 (SD, 3401) vigorous steps per day (p < 0.001), and spent a mean of 2.9 hours (SD, 1.1) per day walking (p < 0.001). Only 16 patients (16.5%) met physical activity guidelines after TKA. BMI (p = 0.017), sex (p = 0.027), and comorbidities (American Society of Anesthesiologists Grade, p = 0.042) were independent factors associated with steps per day after TKA. CONCLUSIONS: One year after TKA, patients had increased walking and moderate to vigorous steps. However, only 16.5% achieved the guideline recommendations for walking activity. BMI, sex, and comorbidities are patient factors that are associated with activity after TKA. Even with improvements in walking, activity level after TKA remains less than that seen for age-matched control subjects. Surgeons should be aware of this when counseling patients undergoing TKA. LEVEL OF EVIDENCE: Level III, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Is range of motion after cruciate-retaining total knee arthroplasty influenced by prosthesis design? A prospective randomized trial.

Improvement in knee flexion is a major expectation for many patients undergoing total knee arthroplasty (TKA). One hundred and twenty two patients were randomized to receive a cruciate-retaining standard or high-flexion TKA. Range of motion (ROM) and functional outcomes were assessed. The high flexion implants had a greater intraoperative ROM than standard implants. The mean flexion preoperatively, intraoperatively and at the one year follow-up was 107.4°, 123.0° and 108.9° in the standard group and 109.9°, 129.1° and 109.7° in the high-flexion TKA group. These differences were not significant preoperatively and at follow-up, but intraoperatively (P < 0.001). In multivariate analysis preoperative knee flexion was the only significant factor influencing knee flexion at follow-up. No differences in the Knee Society Score or SF 36 were observed.

Evidence-based and Patient-centered Indication for Knee Arthroplasty - Update of the Guideline. / Evidenzbasierte und patientenorientierte Indikationsstellung zur Knieendoprothese ­ Update der Leitlinie.

Knee arthroplasty is one of the most frequently performed operations in Germany, with approximately 170000 procedures per year. It is therefore essential that physicians should adhere to an appropriate, and patient-centered indication process. The updated guideline indication criteria for knee arthroplasty (EKIT-Knee) contain recommendations, which are based on current evidence and agreed upon by a broad consensus panel. For practical use, the checklist has also been updated.For this guideline update, a systematic literature research was conducted in order to analyse (inter-)national guidelines and systematic reviews focusing on osteoarthritis of the knee and knee arthroplasty, to answer clinically relevant questions on diagnostic, predictors of outcome, risk factors and contraindications.Knee arthroplasty should solely be performed in patients with radiologically proven moderate or severe osteoarthritis of the knee (Kellgren-Lawrence grade 3 or 4), after previous non-surgical treatment for at least three months, in patients with high subjective burden with regard to knee-related complaints and after exclusion of possible contraindications (infection, comorbidities, BMI ≥ 40 kg/m2). Modifiable risk factors (such as smoking, diabetes mellitus, anaemia) should be addressed and optimised in advance. After meeting current guideline indications, a shared decision-making process between patients and surgeons is recommended, in order to maintain high quality surgical management of patients with osteoarthritis of the knee.The update of the S2k-guideline was expanded to include unicondylar knee arthroplasty, the preoperative optimisation of modifiable risk factors was added and the main indication criteria were specified.

Does the use of patient-specific instrumentation improve resource use in the operating room and outcome after total knee arthroplasty?-A multicenter study.

Patient-specific instrumentation (PSI) in total knee arthroplasty (TKA) has been introduced to reduce instruments and surgical time and to improve implant alignment. The aim of this study was to compare TKA with patient-specific and conventional instrumentation with regard to the use of resources in the operating room (OR), alignment and patient-reported outcome. A total of 139 TKA with PSI or conventional instrumentation were included in three centers. Economic variables of the surgery (number of instrument trays, setup and cut-sew-time), radiological alignment and patient reported outcomes (VAS Pain Scale, Oxford Knee Score, EQ-5D) were assessed after 6 weeks, 6 and 12 months. There was a significant reduction of instrument trays and of time in the OR in the PSI group. The reduction varied between the centers. With strict reorganization, more than 50% of the instrument trays could be reduced while using PSI. There were no significant differences in cut-sew-time, implant position, leg axis, pain and function. The use of PSI was associated with significantly less OR resources. However, the savings did not compensate the costs for this technology.