Hypoxic Conditions Promote Cartilage Repair in a Rat Knee Osteochondral Defect Model via Hypoxia-Inducible Factor-1α.

Bone marrow stimulation is a treatment for articular cartilage injuries that promotes cartilage repair by inducing the migration and accumulation of mesenchymal stem cells (MSCs), but often results in fibrocartilage with limited durability. This study aimed to investigate the effect of hypoxic conditions on cartilage repair using a rat osteochondral defect model. Osteochondral defects (1.

Belt Electrode-Skeletal Muscle Electrical Stimulation Prevents Muscle Atrophy in the Soleus of Collagen-Induced Arthritis Rats.

We investigated the effects of belt electrode-skeletal muscle electrical stimulation (B-SES) on muscle atrophy in collagen-induced arthritis (CIA) rats. Twenty-eight 8-week-old male Dark Agouti rats were immunized with type II collagen and Freund's incomplete adjuvant (day 0). From days 14 to 28, 18 rats received B-SES (50 Hz) four times only on the right hindlimb (STIM), while the contralateral left hindlimb remained unstimulated.

Long-Term Outcomes and Prognostic Factors of Medial Open Wedge High Tibial Osteotomy for Medial Compartment Knee Osteoarthritis or Osteonecrosis.

Medial open wedge high tibial osteotomy (MOWHTO) has led to favorable clinical results since the introduction of locking plates. Surgical indications, techniques, and postoperative alignment are crucial for achieving favorable clinical outcomes. This study analyzed the clinical outcomes of patients after >5 years of post-MOWHTO follow-up to identify the influential factors.

Intermittent hypoxic stimulation promotes efficient expression of Hypoxia-inducible factor-1α and exerts a chondroprotective effect in an animal osteoarthritis model.

Hypoxia-inducible factor-1α plays an important role in the homeostasis of articular cartilage in hypoxic environments. Therefore, modulation of hypoxia-inducible factor-1α by regulating the oxygen environment could be a useful treatment for osteoarthritis. This study aimed to assess the chondroprotective effects of intermittent hypoxia on cultured chondrocytes and an animal model of osteoarthritis.

Effect of Open-Wedge High Tibial Osteotomy and Lateral Retinacular Release on the Articular Cartilage of the Patellofemoral Joint: Analysis Using Magnetic Resonance Imaging T2 Mapping.

After open-wedge high tibial osteotomy (OWHTO), the patella is displaced distally, causing patellofemoral joint degeneration. The objective of this study was to ascertain whether the combination of OWHTO and lateral retinacular release (LRR) can prevent articular cartilage degeneration of the patellofemoral joint using magnetic resonance imaging T2 mapping. This study included 37 patients (37 knees) who underwent OWHTO alone (OWHTO group) and 37 patients (37 knees) who underwent OWHTO with LRR (OWHTO + LRR group) with a correction angle of <10° for varus knee osteoarthritis.

Posteromedial Portal Technique With Bone-Patellar Tendon-Bone Graft for Inside-Out Revision of Anterior Cruciate Ligament Reconstruction.

Bone-patellar tendon-bone (BTB) is a graft material used in anterior cruciate ligament (ACL) reconstruction. We describe creating a femoral tunnel using an inside-out posteromedial (PM) portal technique during anatomic double-bundle ACL reconstruction with a hamstring graft. We hypothesized that applying this femoral tunnel creation method to the revision ACL reconstruction using BTB would enable reconstruction in 1 stage.

The clinical results of bi-cruciate vs posterior stabilized total knee arthroplasty for flexion contracture in osteoarthritic knee.

Background: The improvement of flexion contracture is important in knee arthroplasty since residual flexion contracture postoperatively is associated with decreased quality of life and patient satisfaction. In this study, we investigated the effect of bi-cruciate stabilized (BCS)-type total knee arthroplasty (TKA) as compared to posterior stabilized (PS)-type TKA on osteoarthritic primary knees with flexion contractures.

Methods: 59 TKAs from January 2014 to December 2020, of which 30 were PS-type TKAs (NexGen LPS-flex; 76.

Hypoxia with or without Treadmill Exercises Affects Slow-Twitch Muscle Atrophy and Joint Destruction in a Rat Model of Rheumatoid Arthritis.

The effects of treadmill running under hypoxic conditions on joints and muscles of collagen-induced arthritis (CIA) rats were investigated. CIA rats were divided into normoxia no-exercise, hypoxia no-exercise (Hypo-no), and hypoxia exercise (Hypo-ex) groups. Changes were examined on days 2 and 44 of hypoxia with or without treadmill exercises.

Cartilage degeneration of patellofemoral joint occurs in open wedge high tibial osteotomy, rather than in hybrid closed wedge high tibial osteotomy, during the early postoperative period: A qualitative analysis using MRI T mapping.

Purpose: After high tibial osteotomy, the patella may change position and osteoarthritis of the patellofemoral joint (PFJ) may occur. It was hypothesized that the course of PFJ degeneration would differ between open wedge high tibial osteotomy (OWHTO) and hybrid closed wedge high tibial osteotomy (hybrid HTO). Accordingly, this study aimed to evaluate the qualitative changes in PFJ articular cartilage, during the early postoperative period after OWHTO and hybrid HTO.

Revision Anterior Cruciate Ligament Reconstruction Using Semitendinosus Tendon With Bone Fragment.

After anterior cruciate ligament (ACL) reconstruction, the tibial tunnel becomes widened over time. A revision surgery of the ACL reconstruction is required to fill the widened tunnels. Bone-patellar tendon-bone grafts often are used to fill enlarged bone tunnels.

Analysis of the relationship between the morphology of the proximal tibiofibular joint and lateral hinge fracture in open wedge high tibial osteotomy.

Background: One of the complications of open wedge high tibial osteotomy is lateral hinge fracture, which causes delayed bone healing. In this study, we focused on the morphology of the proximal tibiofibular joint to clarify the influence of this morphology on the occurrence of lateral hinge fracture in open wedge high tibial osteotomy.

Methods: The proximal tibiofibular joint of 58 knees in 55 patients who underwent open wedge high tibial osteotomy was classified as either horizontal or oblique, depending on the morphology of the fibular head.

Prophylaxis of Post-Endoscopic Retrograde Cholangiopancreatography Pancreatitis Using Temporary Pancreatic Stents Versus Rectal Nonsteroidal Anti-inflammatory Drugs: A Randomized Controlled Trial.

Objectives: Both pancreatic stenting and rectal nonsteroidal anti-inflammatory drugs (NSAIDs) prevent post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis. The aim of the study was to compare post-ERCP pancreatitis (PEP) prophylaxis using pancreatic stents and/or rectal NSAIDs prospectively.

Methods: A total of 321 patients undergoing ERCP were studied.

Hypoxia promotes differentiation of pure cartilage from human induced pluripotent stem cells.

While cartilage can be produced from induced pluripotent stem cells (iPSCs), challenges such as long culture periods and compromised tissue purity continue to prevail. The present study aimed to determine whether cartilaginous tissue could be produced from iPSCs under hypoxia and, if so, to evaluate its effects on cellular metabolism and purity of the produced tissue. Human iPSCs (hiPSCs) were cultured for cartilage differentiation in monolayers under normoxia or hypoxia (5% O), and chondrocyte differentiation was evaluated using reverse transcription‑quantitative PCR and fluorescence‑activated cell sorting.

Analysis of Hemodynamic Changes After Medial Patellofemoral Ligament Reconstruction.

The resumption of blood flow is an important factor in the remodeling process of the graft. The purpose of this study is to evaluate hemodynamic changes after medial patellofemoral ligament (MPFL) reconstruction using magnetic resonance angiography (MRA) as the evaluation of graft remodeling. Eleven knees that underwent anatomical MPFL reconstruction with the semitendinosus tendon were studied.

CD81 inhibition with the cytoplasmic RNA vector producing anti-CD81 antibodies suppresses arthritis in a rat CIA model.

Objective: Cluster of differentiation 81 (CD81) is a tetraspanin membrane protein consisting of 4 transmembrane domains and 2 outer membrane loops. CD81 inhibition is a potential treatment for rheumatoid arthritis (RA). Here, we investigated the therapeutic effects of the cytoplasmic RNA vector expressing anti-CD81 antibodies (the anti-CD81 vector) on the ankle joint synovium in collagen-induced arthritis (CIA) rats.

Tibial Condyle Valgus Osteotomy for Ipsilateral Knee Osteoarthritis after Hip Arthrodesis.

We report a case of tibial condylar valgus osteotomy (TCVO) for ipsilateral knee osteoarthritis (OA) after hip arthrodesis. A 58-year-old woman developed right purulent hip arthritis at one month of age and underwent right hip fusion at 16 years old. She visited our department at the age of 57 because her right knee joint pain worsened.

Treadmill running prevents atrophy differently in fast- versus slow-twitch muscles in a rat model of rheumatoid arthritis.

To investigate the effects of treadmill running on two different types of skeletal muscle, we established a rat model of collagen-induced arthritis (CIA). The skeletal muscles studied were the extensor digitorum longus (EDL), which is rich in fast-twitch muscle fibers, and the soleus, which is rich in slow-twitch muscle fibers. The histological and transcriptional changes in these muscles at 14 and 44 days after immunosensitization were compared between rats that were forced to exercise (CIA ex group) and free-reared CIA rats (CIA no group).

Mechanical stimulation of chondrocytes regulates HIF-1α under hypoxic conditions.

We investigated the effects of hypoxia-inducible factor (HIF)-1α on articular cartilage under mechanical stimulation and the associated mechanisms. Chondrocytes, isolated from articular cartilage from the knee, hip, and shoulder joints of Wistar rats, were subjected to 20 % tensile stress under hypoxic (5% O) conditions for 24 h. HIF-1α and aggrecan expression was significantly enhanced with mechanical stimulation under hypoxia but not significantly altered with mechanical stimulation under normoxia.

Sustained Hypoxia Suppresses Joint Destruction in a Rat Model of Rheumatoid Arthritis via Negative Feedback of Hypoxia Inducible Factor-1α.

Hypoxia inducible factor (HIF)-1α has been implicated in the pathogenesis of rheumatoid arthritis (RA). HIF-1α, which is expressed in hypoxia, is reversely suppressed in sustained hypoxia. Here, we investigated the inhibitory effect of hypoxia on arthritis by controlling HIF-1α.

Adjustable-Loop Devices Promote Graft Revascularization in the Femoral Tunnel After ACL Reconstruction: Comparison With Fixed-Loop Devices Using Magnetic Resonance Angiography.

Background: Hamstring tendon grafts are usually fixed in anterior cruciate ligament (ACL) reconstruction using either an adjustable-loop device (ALD) or a fixed-loop device (FLD). The contact area between the graft and the tunnel wall is different between the 2 devices.

Purpose: To determine using magnetic resonance angiography (MRA) whether ALD and FLD result in different blood flow of the graft in the femoral tunnel during the early postoperative period.

Radiologic results of additional single screw fixation with lateral locking plate after hybrid closed-wedge high tibial osteotomy.

Background: Hybrid closed-wedge high tibial osteotomy (hybrid CWHTO) is an effective surgical treatment for medial compartment osteoarthritis of the knee. Our study investigated whether the combination of a lateral locking plate and a single medial screw promoted bone union after hybrid CWHTO.

Methods: The study cohort consisted of 30 patients (15 men and 15 women) who underwent hybrid CWHTO for medial compartment osteoarthritis or spontaneous osteonecrosis of the knee.

Arthroscopic Fixation Technique for Avulsion Fracture of the Posterior Cruciate Ligament From the Tibia.

This study describes an arthroscopic pullout fixation technique for small and comminuted avulsion fractures of the posterior cruciate ligament from the tibia. Intra-articular surgery required 3 arthroscopic portals, the anterolateral, anteromedial, and posteromedial portals. To simplify surgery, the posterolateral portal was omitted.