Clinical and safety outcomes of simultaneous bilateral total knee arthroplasty for Japanese octogenarian patients: a retrospective analysis.

PURPOSE: The demand for simultaneous bilateral total knee arthroplasty (SiBTKA) in older adults is expected to increase with an aging population, thus necessitating evaluating its efficacy and safety. However, there is limited information regarding the clinical outcomes of SiBTKA in older adults, particularly in octogenarians. We aimed to assess the clinical outcomes and safety of SiBTKA in Japanese patients aged ≥ 80 years. METHODS: Of the 176 consecutive knees that underwent SiBTKA between July 2016 and January 2022 at our hospital, 172 were selected. They were divided into two groups according to the patient age as follows: the octogenarian group (≥ 80 years, 74 knees) and the younger control group (< 80 years, 98 knees). In addition, we assessed their preoperative clinical information, clinical outcomes using the Knee Society Score for knee (KSS-K) and function (KSS-F), and the incidence of early (≤ 90 days) and late (> 90 days) postoperative complications. RESULTS: The mean follow-up period was 3.5 years. The KSS-K scores of both groups improved postoperatively than that preoperatively. Both preoperative and postoperative KSS-F scores were lower in the octogenarians; however, their improvement rates were similar to those of the younger controls. We observed no significant intergroup differences in early or late postoperative complications, including infection, systemic complications, periprosthetic fractures, aseptic loosening, and mortality. CONCLUSION: SiBTKA for octogenarians had clinical outcomes and postoperative complication incidence similar to that for younger controls. Therefore, SiBTKA may be a safe and effective treatment option for octogenarians with painful bilateral knee deformities.

Preoperative incidence and risk factors of deep vein thrombosis in Japanese patients undergoing total hip arthroplasty.

PURPOSE: Preoperative deep vein thrombosis (DVT) is a risk factor for postoperative venous thromboembolism (VTE), causing severe mortality. Early detection of preoperative DVT is essential to prevent postoperative VTE. However, little is known regarding preoperative DVT in patients undergoing major surgery. The present study aimed to determine the incidence and risk factors of preoperative DVT in patients admitted for total hip arthroplasty (THA). METHODS: From August 2017 to September 2022, 243 patients admitted for THA at our institution were enrolled in this study. Patients medical records and preoperative laboratory data were retrospectively collected. According to the results of lower-limb ultrasonography, patients were divided into either the non-DVT (n = 136) or DVT (n = 43) group. The incidence of DVT and independent risk factors for preoperative DVT were investigated using univariate and multivariate logistic regression analyses. RESULTS: The mean age was 74.0 ± 8.4 years. Preoperative DVT was diagnosed in 43 of the 243 (17.7%) patients. The risk of DVT was significantly high (p < 0.05) in patients with advanced age, increased D-dimer levels, and malnutrition status, as assessed by the Geriatric Nutritional Risk Index (GNRI). Multivariate analysis showed that advanced age, increased D-dimer level, and malnutrition status assessed by the GNRI were independent risk factors for preoperative DVT. CONCLUSION: A high incidence of preoperative DVT was observed in patients undergoing THA. Advanced age, increased D-dimer levels, and malnutrition assessed by the GNRI increased the risk of preoperative DVT. Screening high-risk subgroups for preoperative DVT is necessary to prevent postoperative VTE.

Clinical and radiological outcomes of total hip arthroplasty in octogenarian patients using a three-dimensional porous titanium cup: a retrospective analysis in Japanese patients.

PURPOSE: Osteointegration of a three-dimensional (3D) porous titanium material has been experimentally proven, but only a few studies have shown the clinical outcomes of a 3D porous titanium cup in the Japanese elderly population. The purpose of this study was to compare the short-and-medium term clinical and radiographic results of total hip arthroplasty (THA) using a 3D porous titanium cup in patients aged ≥ 80 (octogenarians) versus those aged < 80 (younger controls). METHODS: A total of 104 hips that underwent THA using a 3D porous titanium cup (SQRUM TT, Kyocera Medical) were enrolled in the study and were divided into two groups according to age: the octogenarian group (≥ 80, n = 42) and the younger control group (< 80, n = 62). Furthermore, we evaluated patient characteristics, clinical outcomes determined by the Japanese Orthopedic Association score, cup alignment, and incidence of radiolucent lines around the cup. RESULTS: The mean follow-up period was 4.2 and 4.0 years (p = 0.29) for octogenarians and younger controls, respectively. The clinical outcomes were excellent, and no revision surgery occurred until the last follow-up in both groups. The number of patients with radiolucent lines at the final evaluation was 21 of 62 (33.9%) in younger controls and 16 of 42 (38.1%) in octogenarians. CONCLUSION: THA with 3D porous titanium cup for octogenarians had similar clinical outcomes and incidence of radiolucent lines as those of younger controls, suggesting that the 3D porous titanium cup may be useful in THA for octogenarians. Further investigations will confirm its long-term outcomes.

Runx2 and Runx3 differentially regulate articular chondrocytes during surgically induced osteoarthritis development.

The Runt-related transcription factor (Runx) family plays various roles in the homeostasis of cartilage. Here, we examined the role of Runx2 and Runx3 for osteoarthritis development in vivo and in vitro. Runx3-knockout mice exhibited accelerated osteoarthritis following surgical induction, accompanied by decreased expression of lubricin and aggrecan. Meanwhile, Runx2 conditional knockout mice showed biphasic phenotypes: heterozygous knockout inhibited osteoarthritis and decreased matrix metallopeptidase 13 (Mmp13) expression, while homozygous knockout of Runx2 accelerated osteoarthritis and reduced type II collagen (Col2a1) expression. Comprehensive transcriptional analyses revealed lubricin and aggrecan as transcriptional target genes of Runx3, and indicated that Runx2 sustained Col2a1 expression through an intron 6 enhancer when Sox9 was decreased. Intra-articular administration of Runx3 adenovirus ameliorated development of surgically induced osteoarthritis. Runx3 protects adult articular cartilage through extracellular matrix protein production under normal conditions, while Runx2 exerts both catabolic and anabolic effects under the inflammatory condition.

Regulation of osteoarthritis development by ADAM17/Tace in articular cartilage.

INTRODUCTION: A disintegrin and metalloproteinase 17 (Adam17), also known as TNFα-converting enzyme (Tace), is a membrane-anchored protein involved in shedding of TNF, IL-6 receptor, ligands of epidermal growth factor receptor (EGFR), and Notch receptor. This study aimed to examine the role of Adam17 in adult articular cartilage and osteoarthritis (OA) pathophysiology. MATERIALS AND METHODS: Adam17 expression was examined in mouse knee joints during OA development. We analyzed OA development in tamoxifen-inducible chondrocyte-specific Adam17 knockout mice of a resection of the medial meniscus and medial collateral ligament (medial) model, destabilization of the medial meniscus (DMM) model, and aging model. We analyzed downstream pathways by in vitro experiments, and further performed intra-articular administration of an Adam17 inhibitor TAPI-0 for surgically induced mouse OA. RESULTS: Adam17 expression in mouse articular cartilage was increased by OA progression. In all models, Adam17 knockout mice showed ameliorated progression of articular cartilage degradation. Adam17 knockout decreased matrix metallopeptidase 13 (Mmp13) expression in both in vivo and in vitro experiments, whereas Adam17 activation by phorbol-12-myristate-13-acetate (PMA) increased Mmp13 and decreased aggrecan in mouse primary chondrocytes. Adam17 activation enhanced release of soluble TNF and transforming growth factor alpha, a representative EGF ligand, from mouse primary chondrocytes, while it did not change release of soluble IL-6 receptor or nuclear translocation of Notch1 intercellular domain. Intra-articular administration of the Adam17 inhibitor ameliorated OA progression. CONCLUSIONS: This study demonstrates regulation of OA development by Adam17, involvement of EGFR and TNF pathways, and the possibility of Adam17 as a therapeutic target for OA.

Effect of Spinal Alignment Changes on Lower Back Pain in Patients Treated with Total Hip Arthroplasty for Hip Osteoarthritis.

Background and objectives: The influence of changes in spinal alignment after total hip arthroplasty (THA) on improvement in lower back pain (LBP) remains controversial. To evaluate how changes in spinal malalignment correlate with improvement in preoperative LBP in patients who underwent THA for hip osteoarthritis. Materials and Methods: From November 2015 to January 2017, 104 consecutive patients who underwent unilateral THA were prospectively registered. Whole spine X-rays and patient-reported outcomes (PROs) were obtained preoperatively and 12 months postoperatively. The PROs used were the Numerical Rating Scale (NRS) for back pain, EuroQol 5 Dimension, and Short Form-12. Results: Seventy-four (71%) patients with complete data were eligible for the analysis. The sagittal parameters changed slightly but significantly. Coronal alignment significantly improved. Twenty-six (37%) patients had LBP preoperatively. These patients had smaller lumbar lordosis (LL), larger PT, and larger PI minus LL than the patients without LBP. Fourteen (54%) of the 26 patients with preoperative LBP showed pain improvement, but there were no significant differences in the radiographic parameters. Conclusions: Although preoperative LBP was likely to be resolved after THA, there were no significant correlations between alignment changes and LBP improvement. The cause of LBP in patients with hip osteoarthritis (OA) patients might be multifactorial.

Characteristics of three-dimensional acetabular morphology of patients with excellent outcome after rotational acetabular osteotomy over 20 years.

BACKGROUND: Rotational acetabular osteotomy (RAO) is a type of pelvic osteotomy performed to improve the acetabular bony coverage against the femoral head for patients with acetabular dysplasia. The acetabular bony coverage is ideally evaluated three-dimensionally; however, there is a paucity of published data regarding three-dimensional morphology in patients with long-term excellent outcome after RAO. The present study investigated the characteristics of three-dimensional acetabular morphology with long-term excellent outcome after RAO in comparison to patients with normal hip joints and those converted to total hip arthroplasty (THA) after RAO because of osteoarthritis (OA) progression. METHODS: Anteroposterior plain radiograph and computed tomography data of 57 hip joints (17 joints with excellent outcome 20 years or more after RAO, 16 normal joints, and 20 joints converted to THA after RAO) were analyzed. The two-dimensional lateral center-edge (CE) angle from plain radiographs and acetabular anteversion, anterior acetabular sector angle, and posterior sector angle from computed tomography (CT) images were calculated. RESULTS: Compared with patients converted to THA, all parameters in patients with long-term excellent outcome after RAO were similar to those in patients with normal hip joints, particularly in the three-dimensional analyses. The anterior bony coverage was excessive, whereas the posterior bony coverage was deficient in patients converted to THA after RAO. Anterior bony impingement and posterior instability may be the cause of OA progression after RAO. CONCLUSION: Caution must be taken to avoid rotating the separated fragment excessively to the anterior direction during RAO to prevent OA progression and achieve long-term excellent outcome.

2-Methacryloyloxyethyl Phosphorylcholine Polymer Coating Inhibits Bacterial Adhesion and Biofilm Formation on a Suture: An In Vitro and In Vivo Study.

Initial bacterial adhesion to medical devices and subsequent biofilm formation are known as the leading causes of surgical site infection (SSI). Therefore, inhibition of bacterial adhesion and biofilm formation on the surface of medical devices can reduce the risk of SSIs. In this study, a highly hydrophilic, antibiofouling surface was prepared by coating the bioabsorbable suture surface with poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate) (PMB). The PMB-coated and noncoated sutures exhibited similar mechanical strength and surface morphology. The effectiveness of the PMB coating on the suture to suppress adhesion and biofilm formation of methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus was investigated both in vitro and in vivo. The bacterial adhesion test revealed that PMB coating significantly reduced the number of adherent bacteria, with no difference in the number of planktonic bacteria. Moreover, fluorescence microscopy and scanning electron microscopy observations of adherent bacteria on the suture surface after contact with bacterial suspension confirmed PMB coating-mediated inhibition of biofilm formation. Additionally, we found that the PMB-coated sutures exhibited significant antibiofouling effects in vivo. In conclusion, PMB-coated sutures demonstrated bacteriostatic effects associated with a highly hydrophilic, antibiofouling surface and inhibited bacterial adhesion and biofilm formation. Therefore, PMB-coated sutures could be a new alternative to reduce the risk of SSIs.

Midterm results of revision total hip arthroplasty for migrated bipolar hemiarthroplasty in patients with hip osteoarthritis using cementless cup with the rim-fit technique.

PURPOSE: The results of reamed bipolar hemiarthroplasty (BHA) in patients with hip osteoarthritis (OA) are reported to be unfavorable. Acetabular reaming for sufficient bony coverage caused bipolar head migration into the superomedial direction, and most patients required revision surgeries. Several methods are applicable to treat decreased bone stock. This study aimed to investigate the midterm results of revision surgeries using the cementless cup with the rim-fit technique. METHODS: Between 1996 and 2014, acetabular revision surgeries using the cementless cup with the rim-fit technique were performed in 86 hips (74 patients). We evaluated radiographic outcomes, including positional change of the rotation center of the artificial femoral head, presence of implant loosening, and filling of the initial gap. We also evaluated clinical outcomes, including the Harris hip score (HHS), and postoperative complications. RESULTS: The average positional changes from BHA to prerevision surgeries were 8.0 mm superiorly and 4.1 mm medially. The average changes from prerevision to postrevision surgeries were 3.7 mm inferiorly and 2.4 mm laterally. No implant loosening was found in all cases; the initial gap between the acetabular host bone and the acetabular cup was filled in 53 (93%) among 57 hips. The average HHS improved from 65.9 before revision surgeries to 83.8 in the latest follow-up. Dislocation and postoperative periprosthetic fracture occurred in two and five hips, respectively; no cases required rerevision surgeries. CONCLUSION: There were favorable midterm results of the revision total hip arthroplasty for migrated BHA in patients with hip OA using cementless cup with the rim-fit technique.