A kinematically aligned (KA) total knee arthroplasty (TKA) is expected to improve patient satisfaction, but its effect remains controversial. We investigated differences in patient-reported outcomes (PROs) between KA and non-KA TKAs using an implant that reproduces anatomical geometry. TKAs for varus deformity were performed in consecutive 129 patients (149 knees) via a measured resection technique with conventional instruments. The femorotibial angle (FTA), hip-knee-ankle angle (HKAA), and the angle between the joint line and the line perpendicular to the mechanical axis (AJLMA) were measured postoperatively (mean 13.6 months), and an AJLMA of ≥ 2° was defined as kinematic alignment. Patients were assigned to two or three alignment categories in each measurement method, and the Knee Society Scores (KSS) and Japanese Knee Injury and Osteoarthritis Outcome Scores (J-KOOS) was compared among the groups. For patients assessed by FTA, an ADL-related J-KOOS subscale (J-KOOS-A) showed a significant difference between valgus and varus outliers (p < 0.05). When assessed by HKAA, neither the KSS nor J-KOOS subscales were significantly different among groups. When assessed by AJLMA, J-KOOS-A was significantly different between groups, and a group for AJLMA of ≥ 2° had higher scores than a group for AJLMA of < 2° (95% CI 0.323–7.763; p < 0.05). Patients with an AJLMA of ≥ 2° reported significantly higher patient’s satisfaction regarding ADL. This suggests the importance of restoration of the physiological joint line which can be achieved via KA TKAs.

The goal of this study was to investigate the impact of postoperative inclination of the joint line on clinical results after total knee arthroplasty (TKA) using a prosthesis with anatomical geometry. This study included 145 primary cruciate-retaining type of knee prosthesis with anatomical geometry. Three years postoperatively, clinical outcomes including the patient-reported outcomes (PROs) were recorded. Limb alignment was evaluated by the hip-knee-ankle (HKA) axis and inclination of the joint line was assessed by the joint line orientation angle (JLOA). Knees were divided into two groups according to the HKA: in-range (− 3 to 3°) and outlier group (< − 3° or > 3°) or the JLOA: in-range (2–4°) and outlier group (< 2° or > 4°), and clinical outcomes were compared between the groups. Postoperative Knee Society Function Score (KS-FS) was significantly higher in the HKA in-range group than the outlier group (p = 0.01). The Knee Society Knee Score and all subscales of the Knee injury Osteoarthritis Outcome Score were comparable between the groups. A multivariate analysis revealed a significant association between age at operation and postoperative KS-FS > of 80 points. Neither HKA in-range nor JLOA in-range were associated with the higher knee function. In conclusion, TKA-postoperative inclination of the joint line was not relevant to the short-term PROs. Treatment strategies that attempt to make joint line inclination in order to improve postoperative PROs should be avoided, and alignment goals such as kinematic alignment should be considered carefully.

Background: The FINE total knee was developed in Japan and clinical use began in 2001. It has unique design features, including an oblique 3^ofemorotibial joint line that reproduces anatomical geometry. Although 20 years have passed since the FINE knee was clinically used for the first time in Japan, a formal clinical evaluation including patient-reported and radiographic outcomes has not been undertaken.Methods: A total of 175 consecutive primary cruciate-retaining (CR)-FINE total knee arthroplasties (TKAs) at our hospital between February 2015 and March 2017 were included in this study. Three years postoperatively, range of motion (ROM), Knee Society Score (KSS), Knee Injury and Osteoarthritis Outcome Score (KOOS) and Forgotten Joint Score (FJS) were recorded and compared with preoperative scores. Radiographic analyses including mechanical alignment, component alignment, and incidence of radiolucent lines also were undertaken based on the radiographs 3 years postoperatively.Results: One-hundred twenty-two knees (70%) were available for 3-year follow-up data using KOOS, except for the sports subscale. Postoperative KOOS-symptom, −pain and -ADL were > 85 points, but KOOS-sports, −QOL and FJS were less satisfactory. ROM, KSS and all the subscales of KOOS were significantly improved compared with preoperative scores. Postoperative mean FJS was 66 and was significantly correlated with all the subscales of KOOS, but not with postoperative ROM. Radiolucent lines ≧1 mm wide were detected in five knees (4.1%). There were no major complications needing revision surgeries.Conclusions: Patient-reported outcomes (PROs) for symptoms, pain and ADL after the CR-FINE TKA were generally improved, but those for sports, QOL and FJS were improved less. The incidence of radiolucent lines was rare but detected around the femoral components. With the mid- to long-term follow-up, improvements of surgical technique will be necessary to achieve better PROs from patients receiving the FINE knee.

Objectives: Little information is available regarding long-term follow-up of radiographic progression of damage (RPD) to large joints during treatment of rheumatoid arthritis (RA) with biological disease-modifying antirheumatic drugs (bDMARDs). We evaluated 3- to 4-year follow-up results and the associations between RPD and patient background and Larsen grade (LG) of joints. Methods: Seventy-one RA patients receiving bDMARDs for 3 to 4 years or who achieved bDMARD-free status were included. The mean age and disease duration at the start of bDMARDs were 62.4 years and 10.8 years, respectively. A total of 314 joints, including shoulders, elbows, hips, knees, and ankles, were evaluated to determine whether RPD was present by comparing radiographs before and after treatment. Results: RPD was observed in 24 patients (33.8%) and 34 joints (10.8%). Joints with an LG of III or higher had significantly higher rates of RPD than those with LGs I and II. Multivariate logistic regression analysis revealed that stage and health assessment questionnaire (HAQ) score at 18-months were independent risk factors for RPD (cut-off value: 2.5, odds ratio: 7.222 for stage; cut-off value: 0.9375, odds ratio: 6.278 for HAQ at 18-months). Conclusion: Stage, HAQ at 18-months, and LG at the start of bDMARDs were predictive of RPD after 3 to 4 years. bDMARDs should be started before both stage and LG exceed III and the therapeutic strategy should be determined so that HAQ does not exceed 1.0 during treatment.

Regeneration of articular cartilage remains a challenge for patients who have undergone cartilage injury, osteochondritis dissecans and osteoarthritis. Here, we describe a new recombinant silk fibroin with basic fibroblast growth factor (bFGF) binding peptide, which has a genetically introduced sequence PLLQATLGGGS, named P7. In this study, we cultured a human mesenchymal cell line derived from bone marrow, UE6E7-16, in wild-type fibroin sponge (FS) and recombinant silk fibroin sponge with P7 peptide (P7 FS). We compared cell proliferation, chondrogenic differentiation and cartilaginous tissue formation between the two types of sponge. After stimulation with bFGF at 3 ng/mL, P7 FS showed significantly higher cell growth (1.2-fold) and higher cellular DNA content (5.6-fold) than did wild-type FS. To promote chondrogenic differentiation, cells were cultured in the presence of TGF-β at 10 ng/mL for 28 days. Immunostaining of P7 FS showed SOX9-positive cells comparable to wild-type FS. Alcian-Blue staining of P7 FS also showed cartilaginous tissue formation equivalent to wild-type FS. A significant increase in cell proliferation in P7 FS implies future clinical application of this transgenic fibroin for regeneration of articular cartilage. To produce cartilaginous tissue efficiently, transgenic fibroin sponges and culture conditions must be improved. Such changes should include the selection of growth factors involved in chondrogenic differentiation and cartilage formation.

Introduction: We investigated a comparison of clinical outcomes between cruciate-retaining (CR) and posterior-stabilized (PS) total knee arthroplasty. However, it is still controversial which design leads to better clinical results. In clinical settings, choosing either CR or PS is likely based on the surgeon’s preferences. In this study, short-term clinical outcomes between CR and PS in patients who received a single knee prosthesis were compared using propensity score matching. Methods: Two hundred and twelve CR and 43 PS of a single knee prosthesis were enrolled in this study. After propensity score matching, 34 knees each in the CR and PS groups were chosen and were without significant differences in age at operation, gender, BMI, preoperative range of motion (ROM), preoperative femorotibial angle (FTA), and presence or absence of patellar replacement. Clinical scores, including ROM, Knee Society score (KSS), knee injury and osteoarthritis outcome score (KOOS), except for the sports subscale, were compared between the CR and PS groups preoperatively and two years postoperatively. Results: Postoperatively, there were no significant differences in FTA, ROM, or KSS. Preoperative scores for the KOOS except for the pain subscale were comparable between the groups. Postoperatively, however, the PS group had a significantly higher score in the ADL subscale compared to the CR group (PS: 89.5 vs. CR: 80.8, p = 0.017). The KOOS subscales other than activities of daily living (ADL) were comparable between the groups. Conclusions: In this propensity score-matched cohort study, PS showed a better outcome for the ADL than the CR design. These findings suggest that choosing either CR or PS should not depend on the surgeon’s preferences. A PS design may be preferable to CR for elderly patients.