New measurement technique for restoration of the trochlear offset after image-based robotic-assisted total knee arthroplasty: a reliability study

Introduction: The new concepts in total knee arthroplasty (TKA) tend to improve the alignment and ligament balancing after TKA. Nevertheless, the assessment of the anterior compartment is difficult. The purpose of this study was to describe a new measurement technique of trochlear offset restoration on CT-scan after primary robotic-assisted TKA and assess its reliability and repeatability. Method: This monocentric study assessed the trochlear offset restoration on a CT scan after 20 robotic-assisted TKA. To evaluate the trochlear offset restoration, we measured the depth difference between the native and the prosthetic trochlea. Four sequential positions were assessed on the trochlea: at full extension, at 30°, 70°, and 90° flexion. For each of these positions, we compared the highest point of the lateral native condyle and the lateral prosthetic condyle, the highest point of the medial native condyle and the medial prosthetic condyle, the deepest point of the native trochlear groove and the prosthetic trochlea. Two independent reviewers performed the measurements to assess their reliability. To determine intraobserver variability, the first observer performed the measurements twice. Results: The mean age was 67.3 years old ± 8.3. Mean values of the trochlear offset restoration for the medial condyle, trochlear groove and lateral condyle were respectively: 1.0 mm ± 1.6, 1.1 mm ± 1.5, −2.7 mm ± 2.3 in full extension; −3.5 mm ± 1.7, −1.5 mm ± 1.7, −3.9 mm ± 3.9 at 30° flexion; −5.1 mm ± 1.8, 2.1 mm ± 2.7, −3.8 mm ± 1.8 at 70° flexion; 2.0 mm ± 1.4 and 3.1 mm ± 1.5 for the medial and lateral condyles at 90° flexion. The radiographic measurements showed very good to excellent intra-observer and inter-observer agreements with mean kappa values of 0.92 and 0.74. Conclusion: We present a novel measurement technique on CT scan for evaluating the restoration of the trochlear offset after TKA, demonstrating excellent inter and intra-observer reliability

Total knee arthroplasty after opening– versus closing-wedge high tibial osteotomy. A 135-case series with minimum 5-year follow-up

INTRODUCTION: High tibial osteotomy (HTO) is effective in treating isolated medial osteoarthritis of the knee, but subsequent deterioration is inevitable, and total knee arthroplasty (TKA) is then an option. The present study sought to compare TKA following medial opening-wedge HTO (OW-HTO) versus lateral closing-wedge HTO (CW-HTO) in terms of intraoperative data and clinical results. The study hypothesis was that there is no significant difference in clinical results or complications in TKA following OW-HTO or CW-HTO. MATERIAL AND METHOD: A retrospective multicenter (9 centers) study was conducted for the French Society of Orthopedic Surgery and Traumatology (SoFCOT), including 135 TKAs following HTO (58 OW and 77 CW) at a minimum 5 years' follow-up. Mean interval between HTO and TKA was 134 months and was longer in case of CW-HTO (P<0.0001). Mean age at TKA was 65.4 years and older in case of CW-HTO (P=0.021). Tibial slope was greater in case of OW-HTO (P=0.024). Prior to TKA, 55.7% of patients could walk without canes, 98.4% found stairs difficult or impossible and only 19.1% could manage a walking distance greater than 1000m. Mean flexion was 110°; 54.2% of patients showed frontal knee stability and 87.8% sagittal stability; 60.1% had a mechanical axis in varus, without difference according to OW- or CW-HTO. RESULTS: Hardware was almost systematically removed (in 98.5% of cases): in the same step for OW-HTO (P=0.018) or often in 2 steps for CW-HTO. The primary approach was generally re-used (54.2%), but less frequently in the CW-HTO group (P=0.0004). Lateral or medial ligament release was not associated in respectively 78.2% and 79.7% of cases. The TKA implant was usually without stem (87.2%) and was fitted using a conventional technique (74.4%). At a mean 87 months' follow-up, 78.5% of patients could walk without canes, stairs were still difficult or impossible for 67%, and 74.1% could now walk further than 1000m; mean flexion was 110.5°. Overall, 91.5% of patients showed frontal knee stability and 98.2% sagittal stability, without difference according to OW- or CW-HTO. There were 15 complications within 3 months, more often in the OW-HTO group (12.3%) although not significantly, and with no difference in severity. Late complications comprised loosening (5.5%) and infection (3.6%) and were more frequent in the CW-HTO group (12%) (P<0.05). DISCUSSION: The study hypothesis was partially confirmed. The only technical differences concerned hardware removal, often performed in two steps in case of CW-HTO, and TKA approach, which differed from the primary approach in case of CW-HTO. Clinical results were comparable between OW- and CW-HTO, but late complications were more frequent in the CW-HTO group

Management of fixed flexion contracture in primary total knee arthroplasty: recent systematic review

Introduction: This study aimed to systematically review the literature and identify the surgical management strategy for fixed flexion contracture in primary total knee arthroplasty (TKA) surgery, pre-, intra-, and post-operatively. Secondary endpoints were etiologies and factors favoring flexion contracture. Materials and methods: Searches were carried out in November 2023 in several databases (Pubmed, Scopus, Cochrane, and Google Scholar) using the following keywords: “flexion contracture AND TKA”, “fixed flexion deformity AND TKA”, “posterior capsular release AND TKA”, “posterior capsulotomy in TKA”, “distal femoral resection AND TKA”. Study quality was assessed using the STROBE checklist and the Downs and Black score. Data concerning factors or strategies leading to the development or prevention of flexion contracture after TKA were extracted from the text, figures, and tables of the included references. The effect of each predictive factor on flexion contracture after TKA was recorded. Results: Thirty-one studies were identified to meet the inclusion and exclusion criteria. These studies described a variety of preoperative and intraoperative factors that contribute to the development or correction of postoperative flexion contracture. The only clearly identified predictor of postoperative flexion contracture was preoperative flexion contracture. Intraoperative steps described to correct flexion contracture were: soft-tissue balancing (in posterior and medial compartments), distal femoral resection, flexion of the femoral component, and posterior condylar resection. However, no study has investigated these factors in a global model. Discussion: This review identified various pre-, intra-, and post-operative factors predictive of post-operative flexion contracture. In practice, these factors are likely to interact, and it is therefore crucial to further investigate them in a comprehensive model to develop an algorithm for the management of flexion contracture. Level of evidence: I

Ten-year survival and complications of total knee arthroplasty for osteoarthritis secondary to trauma or surgery: A French multicentre study of 263 patients

BACKGROUND: Previous surgical procedures raise technical challenges in performing total knee arthroplasty (TKA) and may affect TKA outcomes. Survival rates of TKA done after trauma or surgery to the knee have not been accurately determined in large populations. The objectives of this retrospective study in 263 patients with TKA after knee trauma or surgery and a follow-up of 10 years were to assess survival, functional outcomes, and the nature and frequency of complications. HYPOTHESIS: Knee trauma or surgery before TKA increases the risk of complications and decreases implant survival. MATERIAL AND METHODS: Two hundred and sixty-three patients (122 [47%] females and 141 [53%] males) underwent TKA between 2005 and 2009 at nine centres in France. Mean age at surgery was 61 years. The patients had knee osteoarthritis secondary to a fracture (n=66), osteotomy (n=131), or ligament injury (n=66). Mean time from trauma or surgery to TKA was 145 months (range, 72-219 months). RESULTS: Major complications were infection (n=12, 4.5%), skin problems (n=8, 3%), and stiffness (n=8, 3%). Ten-year survival to implant exchange for any reason was 89%±2.8%. Flexion range increased by 2.5°±17° (p=0.02) to a mean of 110° (range, 30° to 140°); extension range increased by 4°±7° (p<0.001) to a mean of -1.19 (range, -20° to 0°). Of the 263 patients, 157 (60%) reported little or no pain at last follow-up. Mean postoperative hip-knee-ankle angle was 179°±3.2° (range, 171°-188°). CONCLUSION: TKA performed after knee injury or surgery carries a risk of specific complications (infection, skin problems, and stiffness) and may have a lower survival rate compared to primary TKA

Simultaneous multi slice (SMS) balanced steady state free precession first-pass myocardial perfusion cardiovascular magnetic resonance with iterative reconstruction at 1.5T

Background: Simultaneous-Multi-Slice (SMS) perfusion imaging has the potential to acquire multiple slices, increasing myocardial coverage without sacrificing in-plane spatial resolution. To maximise signal-to-noise ratio (SNR), SMS can be combined with a balanced steady state free precession (bSSFP) readout. Furthermore, application of gradient-controlled local Larmor adjustment (GC-LOLA) can ensure robustness against off-resonance artifacts and SNR loss can be mitigated by applying iterative reconstruction with spatial and temporal regularisation. The objective of this study was to compare cardiovascular magnetic resonance (CMR) myocardial perfusion imaging using SMS bSSFP imaging with GC-LOLA and iterative reconstruction to 3 slice bSSFP. Methods: Two contrast-enhanced rest perfusion sequences were acquired in random order in 8 patients: 6-slice SMS bSSFP and 3 slice bSSFP. All images were reconstructed with TGRAPPA. SMS images were also reconstructed using a non-linear iterative reconstruction with L1 regularisation in wavelet space (SMS-iter) with 7 different combinations for spatial (λσ) and temporal (λτ) regularisation parameters. Qualitative ratings of overall image quality (0 = poor image quality, 1 = major artifact, 2 = minor artifact, 3 = excellent), perceived SNR (0 = poor SNR, 1 = major noise, 2 = minor noise, 3 = high SNR), frequency of sequence related artifacts and patient related artifacts were undertaken. Quantitative analysis of contrast ratio (CR) and percentage of dark rim artifact (DRA) was performed. Results: Among all SMS-iter reconstructions, SMS-iter 6 (λσ 0.001 λτ 0.005) was identified as the optimal reconstruction with the highest overall image quality, least sequence related artifact and higher perceived SNR. SMS-iter 6 had superior overall image quality (2.50 ± 0.53 vs 1.50 ± 0.53, p = 0.005) and perceived SNR (2.25 ± 0.46 vs 0.75 ± 0.46, p = 0.010) compared to 3 slice bSSFP. There were no significant differences in sequence related artifact, CR (3.62 ± 0.39 vs 3.66 ± 0.65, p = 0.88) or percentage of DRA (5.25 ± 6.56 vs 4.25 ± 4.30, p = 0.64) with SMS-iter 6 compared to 3 slice bSSFP. Conclusions: SMS bSSFP with GC-LOLA and iterative reconstruction improved image quality compared to a 3 slice bSSFP with doubled spatial coverage and preserved in-plane spatial resolution. Future evaluation in patients with coronary artery disease is warranted

Etude rétrospective d'une série de 11 prothèses unicompartimentales externes associées à une patellectomie verticale externe (résultats à 5 ans)

LYON1-BU Santé (693882101) / SudocSudocFranceF

Validation française du nouveau score de la knee society et utilisation dans la base de données des prothèses totales de genou

LYON1-BU Santé (693882101) / SudocSudocFranceF