Fluoroscopic and radiostereometric analysis of a bicruciate-retaining versus a posterior cruciate-retaining total knee arthroplasty: a randomized controlled trial.

AIMS: The aim of this study was to compare a bicruciate-retaining (BCR) total knee arthroplasty (TKA) with a posterior cruciate-retaining (CR) TKA design in terms of kinematics, measured using fluoroscopy and stability as micromotion using radiostereometric analysis (RSA). METHODS: A total of 40 patients with end-stage osteoarthritis were included in this randomized controlled trial. All patients performed a step-up and lunge task in front of a monoplane fluoroscope one year postoperatively. Femorotibial contact point (CP) locations were determined at every flexion angle and compared between the groups. RSA images were taken at baseline, six weeks, three, six, 12, and 24 months postoperatively. Clinical and functional outcomes were compared postoperatively for two years. RESULTS: The BCR-TKA demonstrated a kinematic pattern comparable to the natural knee's screw-home mechanism in the step-up task. In the lunge task, the medial CP of the BCR-TKA was more anterior in the early flexion phase, while laterally the CP was more posterior during the entire movement cycle. The BCR-TKA group showed higher tibial migration. No differences were found for the clinical and functional outcomes. CONCLUSION: The BCR-TKA shows a different kinematic pattern in early flexion/late extension compared to the CR-TKA. The difference between both implants is mostly visible in the flexion phase in which the anterior cruciate ligament is effective; however, both designs fail to fully replicate the motion of a natural knee. The higher migration of the BCR-TKA was concerning and highlights the importance of longer follow-up.Cite this article: Bone Joint J 2023;105-B(1):35-46.

Maximal flexion and patient outcomes after TKA, using a bicruciate-stabilizing design.

INTRODUCTION: Physiological motion after total knee arthroplasty (TKA) should result in a large range of motion, which would lead to good clinical outcomes. An adjusted design of a bicruciate-stabilizing TKA was developed to reproduce physiological motion. The aim of this study was to (1) investigate the maximal knee flexion of this knee system, 1 year post-operatively; (2) determine the clinical and functional improvement and compare the outcomes between patients with and without high maximal flexion; and (3) evaluate the adverse events. MATERIALS AND METHODS: In this prospective study, 62 patients with osteoarthritis received a bicruciate-stabilizing TKA. Maximum flexion was measured on a lateral X-ray pre- and post-operatively. Clinical and functional scores and the adverse events were reported up until 2 years after surgery. RESULTS: Pre-operatively, the median (range) maximal flexion was 131.5 (90-153)° and 1 year post-operatively, it was 130 (82-150)°. The results for the clinical scores showed an improvement between pre-operative values and post-operative values. The Kujala score and Knee Osteoarthritis Outcome Score (KOOS) symptoms, sport and quality of life score were better in patients with high maximal flexion (≥ 125°). Ten (serious) adverse device events were reported. CONCLUSIONS: In conclusion, the bicruciate-stabilizing TKA obtained a maximal flexion comparable to the flexion pre-operatively and resulted in good clinical and functional outcomes. Patients with high flexion ability seem to perform better on clinical and functional outcomes. Furthermore, the adjusted design of the bicruciate-stabilizing TKA reduced the number of adverse events. LEVEL OF EVIDENCE: Prospective cohort study, Level II.

Age, gender, functional KSS, reason for revision and type of bone defect predict functional outcome 5 years after revision total knee arthroplasty: a multivariable prediction model.

PURPOSE: The number of revision total knee arthroplasties (rTKA) is increasing. Unfortunately, not all patients benefit from revision surgery. The aim of this study was to develop a clinical prediction model that can be used to predict the functional outcome 5 years after rTKA. METHODS: Data of patients receiving rTKA at Sint Maartenskliniek, Nijmegen, The Netherlands, from 2004 onwards were prospectively collected. Demographic and clinical variables and patient-reported outcome scores were collected and considered as potential predictors. Beneficial outcome was defined as an increase of ≥ 20 points on the functional knee society scores (fKSS) or an absolute fKSS ≥ 80 points 5 years after surgery. The prediction model was developed using backward logistic regression. Regression coefficients were converted into an easy to use prediction rule. RESULTS: Overall, 295 rTKA patients were included of whom 157 (53%) had beneficial fKSS 5 years later. Age, gender, femoral bone defects, preoperative fKSS, and stiffness as reason for revision were included in the model. Men had a higher chance of beneficial fKSS than women (OR 1.59, 95% CI 0.91-2.78). Patients with major bone defects (OR 0.44, 95% CI 0.22-0.85), higher age (IQR OR 0.39, 95% CI 0.26-0.58), higher preoperative fKSS (IQR OR 0.42, 95% CI 0.30-0.59), and severe stiffness (OR 0.48, 95% CI 0.20-1.15) had a lower chance of successful outcome. The model's AUC was 0.76, 95% CI 0.70-0.81. CONCLUSION: Easily determinable characteristics of patients who need rTKA can be used to predict future functional outcome. Young men with low preoperative fKSS without severe stiffness are more likely to achieve a beneficial outcome. LEVEL OF EVIDENCE: IV.

Stability and alignment do not improve by using patient-specific instrumentation in total knee arthroplasty: a randomized controlled trial.

PURPOSE: The primary aim of the study was to examine stability and alignment after total knee arthroplasty (TKA) using patient-specific instrumentation (PSI) and conventional instrumentation (CI). The hypothesis was that stability and alignment would be better using PSI than CI, 12 months postoperatively. The secondary aim included the evaluation of clinical outcomes after TKA. METHODS: In this prospective randomized controlled trial, 42 patients with knee osteoarthritis received a Genesis II PS prosthesis with either PSI or CI. Patients visited the hospital preoperatively and postoperatively after 6 weeks and 3 and 12 months. To evaluate stability, varus-valgus laxity was determined in extension and flexion using stress radiographs 12 months postoperatively. Three months postoperatively, a long-leg radiograph and CT scan were obtained to measure hip-knee-ankle (HKA) alignment and component rotation. Furthermore, frontal and sagittal alignment of the components, the Knee Society Score, VAS Pain, VAS Satisfaction, Knee injury and Osteoarthritis Outcome score, Patella score (Kujala), University of California Los Angeles activity score, anterior-posterior laxity, (serious) adverse device-related events, and intraoperative complications were reported. The clinical outcomes were compared using independent t tests or non-parametric alternatives, and repeated measurements ANOVA with a significance level of p < 0.05. RESULTS: No significant differences were found between the two groups regarding stability, HKA angle, and rotational alignment. In four patients, the PSI did not fit correctly on the tibia and/or femur requiring intraoperative modifications. Both groups improved significantly over time on all clinical outcomes, with no significant differences between the groups 12 months postoperatively. The PSI group showed less tibial slope than the patients in the CI group [PSI 2.6° versus CI 4.8° (p = 0.02)]. Finally, the PSI group more frequently received a thinner insert size than the CI group (p = 0.03). CONCLUSIONS: Patients operated with PSI did not differ from CI in terms of stability and alignment. However, in the PSI group ligament releases were more often required intraoperatively. Furthermore, the two methods did not show different clinical results. It seems that the preoperative planning for the PSI facilitates more conservative bone cuts than CI, but whether this is clinically relevant should be investigated. Since PSI is more expensive and time consuming than CI, and does not outperform CI with regard to clinical results, we recommend to use CI. LEVEL OF EVIDENCE: I.

Single-stage total knee arthroplasty and osteotomy as treatment of secondary osteoarthritis with severe coronal deviation of joint surface due to extra-articular deformity.

PURPOSE: Severe extra-articular deformities can be treated with single-stage total knee replacement (TKA) and osteotomy. Aim of this study was to examine the patient-reported outcome measures (PROMs) and the complications after single-stage TKA and osteotomy. We hypothesized patients achieve good outcome after single-stage TKA and osteotomy, which is comparable to outcome after primary TKA without deformity. METHODS: Twenty-one patients with severe extra-articular deformity who underwent single-stage TKA and deformity-correcting osteotomy were reviewed and invited to fill in PROMs including the Oxford Knee Score, the Short Form-12, a Visual Analogue Scale for pain, and questions about satisfaction and quality of life. RESULTS: The mean follow-up period was 64 months. Ten patients were treated with TKA and supracondylar femoral osteotomy. Although PROMs showed good results (mean quality of life score was 85 out of 100), two patients had a revision of the osteotomy due to non-union. Eleven patients were treated with TKA and high tibial osteotomy. Patients were satisfied with the results (mean quality of life score was 81 out of 100). Two patients developed infection requiring debridement, resulting in one arthrodesis and one gastrocnemius transfer for wound closure. CONCLUSION: In general, patients were satisfied with the postoperative result. Outcome was comparable to patients after primary TKA in the literature. However, serious complications need to be taken into account. LEVEL OF EVIDENCE: III.

Revision Total Knee Arthroplasty for Instability-Outcome for Different Types of Instability and Implants.

BACKGROUND: Given the mixed outcome after revision total knee arthroplasty (TKA) for instability in the literature and the relative high recurrence of instability, we were interested in the outcome of a cohort of patients operated for various types of clinical instability and with different types of implants. METHODS: A total of 77 patients with unstable TKA were completely revised (19 hinged and 58 condylar implants). We classified the patients in 3 instability groups based on the literature: (1) anterior-posterior flexion instability (N = 29); (2) medial-lateral flexion instability (N = 16); and (3) multiplane instability (N = 32). Patients were evaluated up to 24 months postoperatively, concerning Knee Society clinical rating system, range of motion, visual analog scale (VAS) pain, and VAS satisfaction. RESULTS: For the total group, all outcome scores improved, but substantial residual pain (VAS = 41) was reported. For type of instability, the clinical outcome was similar for all the groups. For type of implant, the hinged group had lower postoperative outcome scores but similar satisfaction scores compared with those in the condylar group. There was a considerable number of insert changes and secondary patellar resurfacing in the condylar group compared with no reoperations in the hinged group. Recurrent instability was not seen in the anterior-posterior flexion instability group and in patients who received a condylar constraint-type implant. CONCLUSIONS: We recommend 3 options in revision TKA for instability: (1) hinged implants in cases with severe ligament instability in multiple planes or bone loss, (2) condylar implants with a posterior-stabilized insert in cases with isolated posterior cruciate ligament insufficiency, and (3) condylar implants with condylar constraints in all other cases.

Predictive factors of length of hospital stay after primary total knee arthroplasty.

PURPOSE: To reduce post-operative length of hospital stay (PLOS) after primary total knee arthroplasty (TKA), the fast-track method was introduced which focusses on mobilising the patient within 2 h after surgery. The aim of this prospective study was to identify the factors that predict PLOS using the fast-track method. METHODS: In a consecutive series from July 2012 to November 2012, all patients who were admitted for a primary TKA (Genesis II prosthesis, Smith and Nephew, Memphis, TN) were included in a prospective study. Demographic and relevant preoperative, perioperative and post-operative parameters for PLOS were collected. Multivariate linear regression analysis was performed to identify predictive factors. RESULTS: In total, 240 patients were included (59.6% female) with a median age of 64.1 years (range 38-90). Median PLOS was 5 days (range 3-19). The predictive model suggested that ASA score (American Society of Anesthesiologists' physical status classification) wound exudate and range of motion (ROM) at the day of surgery (day 0) were significant predictive factors for PLOS using the fast-track procedure after TKA (adjusted R(2) = 0.43). CONCLUSIONS: Predictive factors for PLOS after TKA were ASA score, wound exudate and ROM at day 0. Adjustments in patient counselling, nursing ward, mode of physiotherapist training and discharge criteria regarding wound exudate may result in a further reduction of post-operative length of hospital stay. LEVEL OF EVIDENCE: Prognostic studies: high-quality prospective cohort study, Level I.

Medial patellofemoral ligament reconstruction for patellar maltracking following total knee arthroplasty is effective.

PURPOSE: Maltracking of the patella after total knee arthroplasty (TKA) remains a well-recognized problem. The medial patellofemoral ligament (MPFL) has shown to be important for patellar stabilization and reconstructions of the MPFL have already shown excellent functional outcomes for patellar instability of the native knee. Nevertheless, there is only limited literature on using an MPFL reconstruction for correction of patellar maltracking after TKA. In this retrospective study, a consecutive case series was evaluated. METHODS: Between 2007 and 2010, nine patients (nine knees) with anterior knee pain and symptomatic (sub)luxations of the patella after primary or revision TKA were treated by reconstruction of the MPFL in combination with a lateral release. In two cases, an additional tibial tuberosity transfer was performed, due to insufficient per-operative correction. Pre-operative work-up included a CT scan to rule out component malrotation and disorders in limb alignment. Pre- and post-operative patellar displacement and lateral patellar tilt were measured on axial radiographs. Clinical outcome was evaluated using the visual analogue scale (VAS) satisfaction, VAS pain, dislocation rate and Bartlett patella score. RESULTS: Median patellar displacement improved from 29 mm (0-44) to 0 mm (0-9) post-operatively. Median lateral patellar tilt was 45° (23-62) pre-operative and changed to a median 15° (-3 to 21) post-operative. Median VAS satisfaction was 8 (5-9) and only one patient reported a subluxing feeling afterwards. The Bartlett patella score displayed a diverse picture. CONCLUSIONS: Patellar maltracking after primary or revision TKA without malrotation can effectively be treated by MPFL reconstruction in combination with a lateral release. Only in limited cases, an additional tibial tuberosity transfer is needed. LEVEL OF EVIDENCE: IV.

Popliteal pseudoaneurysm after total knee arthroplasty: a report of 3 cases.

Although the incidence of vascular injuries after total knee arthroplasty is quite low, clinical outcome could be significantly impaired. Quick response and accurate management are important to achieve the best possible outcome. We present 3 cases of popliteal pseudoaneurysm formation after total knee arthroplasty and their treatment by endovascular stenting together with a review of literature.

Technical note: easy graft passage without posterior portals in PCL reconstruction.

Graft passage during arthroscopically assisted, single-bundle transtibial PCL reconstruction is a technically demanding surgical procedure. We propose the use of a so called Deschamps clamp, originally designed for cerclage wire transport, in combination with a meniscal repair needle with an eye. This facilitates easy passage of a pull-through needle and obviates extensive debridement of the tibial insertion. Posterior portals are not needed.

Fatigue in knee and hip osteoarthritis: the role of pain and physical function.

OBJECTIVES: It is suggested that serious levels of fatigue are present in nearly half of patients with OA. However, it is unclear which dimensions of fatigue are involved, if fatigue is related to pain and physical function, and if fatigue is influenced by therapy. The aims of this study were to measure levels of different dimensions of fatigue before and after evidenced-based conservative treatment and to investigate the association between fatigue and pain and physical function in patients with knee or hip OA. METHODS: In this observational cohort study, levels of different dimensions of fatigue were measured in knee and/or hip OA patients before and after 12 weeks of conservative treatment. Cross-sectional and longitudinal relations between (change in) fatigue dimensions and (change in) pain or physical function were studied using association models, controlling for predefined possible confounders. RESULTS: A total of 231 patients was included, with 47% experiencing severe fatigue. A small decrease in levels of fatigue was seen after standardized treatment. The level of fatigue severity was cross-sectionally and longitudinally associated with physical function, whereas the level of physical fatigue was cross-sectionally and longitudinally associated with pain and physical function. No confounders were identified. CONCLUSIONS: Important levels of fatigue are common in knee and hip OA patients. After evidence-based tailored conservative treatment targeted to improve pain and physical function, a small decrease in fatigue levels was found. Reduction in levels of different fatigue dimensions were related to the change in physical function and pain.