Feasibility and Safety of a Novel Leg Exercise Apparatus for Venous Thromboembolism Prophylaxis after Total Joint Arthroplasty of the Lower Extremities-A Pilot Study.

Venous thromboembolism (VTE) is a severe complication in orthopedic surgeries. Herein, we developed a novel leg exercise apparatus (LEX) to encourage postoperative limb movement in bedridden patients to prevent VTE. We aimed to evaluate its feasibility and safety in individuals at risk of VTE.

Biological fixation between calcium phosphate-hybridized tendon graft and tibial bone tunnel in anatomic single-bundle ACL reconstruction - A case report.

The purpose of this study was to histologically observe a specimen of a calcium phosphate (CaP)-hybridized tendon graft-bone interface at the posterior side of tibial bone tunnel obtained during the revision anterior cruciate ligament (ACL) reconstruction. We present the case of a 15-year-old female who was returning to sports 7 months and 12 days after primary anatomic single-bundle ACL reconstruction with no instability. Re-rupture was diagnosed 9 months and 12 days after the surgery.

Safety and feasibility of using calcium phosphate hybridization method for quadriceps tendon-bone graft in anterior cruciate ligament reconstruction.

Background: To improve tendon-to-bone healing in anterior cruciate ligament (ACL) reconstruction, a novel technique via the calcium phosphate (CaP) hybridization method for tendon graft using an alternate soaking process was developed. The use of the CaP hybridization method for quadriceps tendon-bone (QTB) graft in ACL reconstruction has not been reported in previous studies. Thus, this clinical trial aimed to clarify the safety and feasibility of using CaP hybridization method for quadriceps tendon-bone (QTB) graft in ACL reconstruction.

Development of fibrocartilage layers in the anterior cruciate ligament insertion in rabbits.

Background: A detailed evaluation focusing on the fibrocartilage layers in the anterior cruciate ligament (ACL) insertion is necessary to consider regeneration of the insertion. This study examined the development of the fibrocartilage layers in the ACL tibial insertion in rabbits by quantitative morphometric evaluations based on histological and immunohistochemical analyses.

Methods: Male Japanese white rabbits were used because of their history of use for histomorphometric analyses of the ACL insertion and to eliminate the influence of female hormones on the ACL.

Morphological changes in the femoral and tibial bone tunnels after anatomic single-bundle anterior cruciate ligament reconstruction using a calcium phosphate-hybridized tendon graft in 2years of follow-up.

Introduction: A calcium phosphate (CaP)-hybridized tendon graft improves tendon-to-bone healing. The purpose of the study was to evaluate the progression of morphological changes in the femoral and tibial bone tunnels after anatomic single-bundle anterior cruciate ligament (ACL) reconstruction using the CaP-hybridized tendon graft versus an untreated tendon graft during 2 years of follow-up.

Hypothesis: We hypothesized that the CaP-hybridized tendon graft would prevent the progression of bone tunnel enlargement compared with the untreated tendon graft.

Anatomic single-bundle anterior cruciate ligament reconstruction using a calcium phosphate-hybridized tendon graft: a randomized controlled trial with 2 years of follow-up.

Background: To improve tendon-to-bone healing in anterior cruciate ligament (ACL) reconstruction, a novel technique via calcium phosphate (CaP)-hybridized tendon graft using an alternate soaking process was developed. The purpose of this study was to evaluate the clinical results of anatomic single-bundle ACL reconstruction using the CaP-hybridized tendon graft with up to 2 years follow-up, and compare the outcome with conventional ACL reconstruction and preoperative data.

Methods: Ninety patients who required anatomic single-bundle ACL reconstruction were randomized to undergo either the CaP-hybridized tendon graft method (CaP group, n = 45) or the conventional method (conventional group, n = 45).

Formation of osteon-like structures in unidirectional porous hydroxyapatite substitute.

Unidirectional porous hydroxyapatite (UDPHAp) bone substitute comprises a microstructure of cross-sectionally oval pores with diameters ranging from 30 to 300 µm. Bone remodeling within the UDPHAp is expected upon implantation into bone; however, the mechanism and factors influencing this bone growth remain unclear. The objectives of the present study were to assess the vasculature and microstructure of newly formed bone and to determine how bone formation is affected by load transfer and UDPHAp pore size.

Extension of knee immobilization delays recovery of histological damages in the anterior cruciate ligament insertion and articular cartilage in rabbits.

[Purpose] To investigate the influence of knee immobilization period on recovery of histological damages in the anterior cruciate ligament (ACL) insertion and articular cartilage in rabbits. This knowledge is important for determining the appropriate rehabilitation approach for patients with ligament injuries, fracture, disuse atrophy, and degenerative joint disease. [Materials and Methods] Forty-eight male Japanese white rabbits were divided equally into the remobilization and control groups.

Risk factors of cervical surgery related complications in patients older than 80 years.

Introduction: With an aging population, the proportion of patients aged ≥80 years requiring cervical surgery is increasing. Surgeons are concerned with the high incidence of complications in this population, because "age" itself has been reported as a strong risk factor for complications. However, it is still unknown which factors represent higher risk among these elderly patients.

A novel exercise device for venous thromboembolism prophylaxis improves venous flow in bed versus ankle movement exercises in healthy volunteers.

Purpose: Venous thromboembolism prophylaxis is crucial. To facilitate active ankle movement in postoperative and bedridden patients, we developed a novel leg exercise apparatus (LEX). We investigated the effect of the LEX by comparing increases in lower extremity venous flow during different modes of exercise using the LEX.

Complications Associated With Spine Surgery in Patients Aged 80 Years or Older: Japan Association of Spine Surgeons with Ambition (JASA) Multicenter Study.

Study Design: Retrospective study of registry data.

Objectives: Aging of society and recent advances in surgical techniques and general anesthesia have increased the demand for spinal surgery in elderly patients. Many complications have been described in elderly patients, but a multicenter study of perioperative complications in spinal surgery in patients aged 80 years or older has not been reported.

Risk Factors for Delirium After Spine Surgery in Extremely Elderly Patients Aged 80 Years or Older and Review of the Literature: Japan Association of Spine Surgeons with Ambition Multicenter Study.

Study Design: Retrospective database analysis.

Objective: Spine surgeries in elderly patients have increased in recent years due to aging of society and recent advances in surgical techniques, and postoperative complications have become more of a concern. Postoperative delirium is a common complication in elderly patients that impairs recovery and increases morbidity and mortality.

Calcium phosphate-hybridized tendon grafts reduce femoral bone tunnel enlargement in anatomic single-bundle ACL reconstruction.

Purpose: This study aimed to clarify the effect of calcium phosphate (CaP)-hybridized tendon grafting versus unhybridized tendon grafting on the morphological changes to the bone tunnels at the aperture 1 year after anatomic single-bundle anterior cruciate ligament (ACL) reconstruction.

Methods: Seventy-three patients were randomized to undergo the CaP (n = 37) or the conventional method (n = 36). All patients underwent computed tomography (CT) evaluation 1 week and 1 year post-operatively.

Differences in placement of calcium phosphate-hybridized tendon grafts within the femoral bone tunnel during ACL reconstruction do not influence tendon-to-bone healing.

Background: Calcium phosphate (CaP)-hybridization of tendon grafts has been shown to improve tendon-to-bone healing. The purpose of this study was to clarify the influence of different tendon graft placement methods on tendon-to-bone healing using CaP-hybridized tendon grafts in anterior cruciate ligament (ACL) reconstructions in rabbits.

Methods: We compared two methods of tendon graft placement within the femoral bone tunnel: suspension of the tendon graft within the bone tunnel (suspension group) and implantation of the tendon graft coherent with the bone socket (coherence group).

Influence of Knee Immobilization on Chondrocyte Apoptosis and Histological Features of the Anterior Cruciate Ligament Insertion and Articular Cartilage in Rabbits.

This study examined the influence of immobilization on chondrocyte apoptosis and histological features of the anterior cruciate ligament (ACL) insertion and knee articular cartilage in rabbits. Forty-eight male Japanese white rabbits were assigned to an immobilization ( = 24) or sham ( = 24) group. Rabbits in the immobilization group underwent complete unilateral surgical knee immobilization and rabbits in the sham group underwent a sham surgery.

Tumor Occupation in the Spinal Canal and Clinical Symptoms of Cauda Equina Schwannoma: An Analysis of 22 Cases.

Study Design: Retrospective, radiological study.

Purpose: To determine the relationship between clinical symptoms and the extent of tumor occupation of the spinal canal by cauda equina schwannoma.

Overview Of Literature: Little is known about the relationship between the size of tumors of the cauda equina and the manifestation of clinical symptoms.

Effect of Calcium Phosphate-Hybridized Tendon Graft in Anatomic Single-Bundle ACL Reconstruction in Goats.

Background: We previously developed a novel technique using an alternate soaking process that improves tendon-bone healing by hybridizing the tendon graft with calcium phosphate (CaP). However, the effects of the CaP-hybridized tendon graft on anatomic single-bundle anterior cruciate ligament (ACL) reconstruction remain unclear.

Purpose: To determine the effects of CaP-hybridized tendon grafts compared with untreated tendon grafts 6 months after anatomic single-bundle ACL reconstruction using a goat model.

The use of a novel in-bed active Leg Exercise Apparatus (LEX) for increasing venous blood flow.

Objective: The incidence of pulmonary embolism (PE) and leg deep vein thrombosis (DVT) has increased in recent years in association with aging and an increase in the number of bedridden individuals. We developed an active in-bed leg exercise apparatus labeled the Leg Exercise Apparatus (LEX) for DVT prevention. We compared the effect of leg exercises performed using the LEX to conventional active ankle exercises on increased blood flow.

Near-infrared fluorescence imaging with indocyanine green-lactosomes in a mouse model of rheumatoid arthritis.

Objectives: The early diagnosis and treatment of rheumatoid arthritis (RA) is important to reduce joint destruction. Many of the current imaging techniques have disadvantages, such as the need for contrast agents and interpretation by specialists. Fluorescence imaging is an emerging technique that overcomes some of these problems.

Muscle activity in the lower limbs during push-down movement with a new active-exercise apparatus for the leg.

[Purpose] Lower-limb deep vein thrombosis is a complication of orthopedic surgery. A leg-exercise apparatus named "LEX" was developed as a novel active-exercise apparatus for deep vein thrombosis prevention. Muscle activity was evaluated to assess the effectiveness of exercise with LEX in the prevention.

Simultaneous Three-Dimensional Analysis of Cervical Spine Kinematics in the Axial and Sagittal Views during a Simulated Frontal Impact: Differences between Tensed and Relaxed States.

Study Design: Prospective experimental study on humans.

Purpose: To determine whether postural differences during a low-speed impact are observed in the sagittal and axial views, particularly in a relaxed state.

Overview Of Literature: Three-dimensional motion capture systems have been used to analyze posture and head-neck-torso kinematics in humans during a simulated low-speed impact, yet little research has focused on the axial view.

A novel apparatus for active leg exercise improves venous flow in the lower extremity.

Background: Venous thromboembolism is a serious complication associated with major orthopedic surgery to the lower extremities. Although active ankle exercise is recommended, patients with postoperative pain may have difficulty moving their ankles. Therefore, we developed a novel leg exercise apparatus (LEX) to facilitate active ankle movement during the early postoperative period.

Bone Regeneration and Remodeling within a Unidirectional Porous Hydroxyapatite Bone Substitute at a Cortical Bone Defect Site: Histological Analysis at One and Two Years after Implantation.

Unidirectional porous hydroxyapatite (UDPHAp) is an artificial bone substitute with a unique microstructure consisting of 100-300-µm oval pores that present the material unidirectionally. UDPHAp has a compression strength of 14 MPa and a porosity of 75%, which promotes cell migration and capillary formation within the material. Despite these advantageous properties, bone remodeling and bone formation with UDPHAp remain unclear.

Influence of mechanical unloading on histological changes of the patellar tendon insertion in rabbits.

Background: The purpose of this study was to clarify the influence of mechanical unloading on histological changes of the patellar tendon (PT) insertion in rabbits.

Materials And Methods: The PT was completely released from stress by drawing the patella toward the tibial tubercle with a stainless steel wire installed between the patella and tibial tubercle (mechanical unloading group, n=28). The animals of the sham group underwent the same surgical procedure; however, the wire was not tightened (n=28).