Publications by authors named "Naoya Hirosawa"

Article Synopsis
  • A study compared changes in the long head of the biceps tendon based on different types of rotator cuff tears in a rat model, focusing on how these changes correlate with tendon degeneration.
  • Ninety-six rats were divided into groups based on specific tears, and various imaging and histological methods were used to analyze tendon changes over time.
  • Results showed that rats with anterior and anterosuperior tears had significantly greater degeneration and thickening in the biceps tendon compared to the control group, indicating a strong relationship between rotator cuff damage and biceps tendon health.
View Article and Find Full Text PDF

The rat mono-iodoacetate (MIA) arthritis model has been used in studies on the hip, knee, and ankle joints. Few studies have explored its utility in shoulder arthritis research, and none have evaluated the effects of time and different MIA doses on arthritis progression. Therefore, we developed a rat MIA shoulder arthritis model to evaluate articular changes through radiological and histological analyses.

View Article and Find Full Text PDF

Background: Although arthroscopic subacromial decompression (ASD) is a commonly used procedure during arthroscopic rotator cuff repair (ARCR), the effect of ASD on the clinical outcomes for ARCR is controversial. The purpose of this study was to compare the clinical outcomes of ARCR with or without ASD.

Methods: Patients (n = 315 with 320 shoulders) who underwent ARCR for small to medium-sized rotator cuff tears were followed for at least 24 months.

View Article and Find Full Text PDF

Background: Autologous vein wrapping (VW) is used in the treatment of recurrent chronic constriction neuropathy and traumatic peripheral nerve injury. However, use of autologous veins is limited by the inability to obtain longer veins of sufficient length for larger sites. Frozen allograft tissue has several advantages, including its availability for large grafts, avoidance of donor-site morbidity, and shorter operation time.

View Article and Find Full Text PDF

Decompression surgery (DS) is a standard treatment for chronic nerve compression injuries; however, the mechanisms underlying its effects remain unclear. Here, we investigated the effects of DS on messenger RNA (mRNA) expression of tumor necrosis factor-α (TNF-α) and T cell recruitment in a rat sciatic nerve (SN) chronic constriction injury (CCI) model. Male Wistar rats were subjected to CCI to establish a model of SN injury (CCI group).

View Article and Find Full Text PDF

Schwann cells (SCs) are known to produce extracellular vesicles (EV) that participate in cell-cell communication by transferring cargo to target cells, including mRNAs, microRNAs, and biologically active proteins. Herein, we report a novel mechanism whereby SC EVs may regulate PNS physiology, especially in injury, by controlling the activity of TNFα. SCs actively sequester tumor necrosis factor receptor-1 (TNFR1) into EVs at high density, accounting for about 2% of the total protein in SC EVs (~1000 copies TNFR1/EV).

View Article and Find Full Text PDF

Study Design: Retrospective observational study.

Purpose: We investigated the correlation between T2 relaxation times and clinical symptoms in patients with cervical radiculopathy caused by cervical disk herniation.

Overview Of Literature: There are currently no imaging modalities that can assess the affected cervical nerve roots quantitatively.

View Article and Find Full Text PDF

Undifferentiated pleomorphic sarcoma (UPS) is a high-grade, aggressive, soft tissue sarcoma that is often fatal. Although there are reports describing associations of sarcoma and skin lesions such as burns, radiation, and trauma, to our knowledge, UPS development in a keloid scar has not been reported. Herein, we present the case of a 76-year-old woman who had undergone surgery for endometrial cancer, 5 years before.

View Article and Find Full Text PDF

We sought to assess the utility of simultaneous apparent T2 mapping and neurography with the nerve-sheath signal increased by inked rest-tissue rapid acquisition of relaxation-enhancement imaging (SHINKEI-Quant) for the quantitative evaluation of compressed nerves in patients with lumbar radiculopathy. Thirty-two patients with lumbar radiculopathy and 5 healthy subjects underwent simultaneous apparent T2 mapping and neurography with SHINKEI-Quant. Regions of interest (ROIs) were placed in the lumbar dorsal root ganglia (DRG) and the spinal nerves distal to the lumbar nerves bilaterally at L4-S1.

View Article and Find Full Text PDF

The purpose of this study was to try oblique lateral interbody fusion (OLIF) using percutaneous pedicle screws (PPS) with mobility. Twelve patients who underwent single-level OLIF were observed for at least one year. These included 6 patients with conventional PPS (rigid group), and 6 with movable PPS (semi-rigid group).

View Article and Find Full Text PDF

Desmoplastic fibroma of the bone (DFB) is a notably rare, lytic, locally aggressive but nonmetastatic, primary benign bone tumor in patients less than 30 years old. As the recommended primary treatment for DFB, wide resection is preferred to curettage from the perspective of recurrence but wide resection of DFB in the pelvis such as in the acetabulum could result in greater functional loss, suggesting the need for conservative treatments. However, there is no report on long-term follow-up following conservative treatment for DFB.

View Article and Find Full Text PDF

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare inflammatory disorder with multiple phenotypes. The syndrome has identifiable radiologic characteristics that are the most important when making a diagnosis. X-rays of cases diagnosed with SAPHO syndrome reveal sclerotic lesions or mixed lytic and sclerotic lesions.

View Article and Find Full Text PDF

Advanced gastric cancer with bone metastasis has a very poor prognosis with short median survival. To the best of our knowledge, no reports in literature have described extensive recovery of paralysis with multimodality treatment without surgery in these cases. This report describes the case of a 52-year-old severely paralyzed female patient with spinal metastasis from advanced gastric cancer.

View Article and Find Full Text PDF

Unlabelled: Lower limb muscle mass and grip loss may be risk factors for vertebral compression fractures in women.

Purpose: We examined the relationship between bone mineral density, bone strength, skeletal muscle mass, grip strength, and skin autofluorescence (SAF) in women with osteoporotic vertebral compression fractures (VCF).

Methods: A total of 1039 women (mean age 73.

View Article and Find Full Text PDF

Study Design: Controlled laboratory study.

Purpose: This study aimed to evaluate the in vitro pharmacological activity of growth factors (GFs) in freeze-dried platelet-rich plasma (FD-PRP) after storage for 4 weeks.

Overview Of Literature: Freshly prepared PRP is a rich source of many GFs.

View Article and Find Full Text PDF

There is no imaging modality to quantitatively evaluate compressed cervical nerve roots in cervical radiculopathy. Here we sought to evaluate the usefulness of simultaneous apparent T2 mapping and neurography with nerve-sheath signal increased with inked rest-tissue rapid acquisition of relaxation-enhancement imaging (SHINKEI-Quant) to evaluate compressed nerves quantitatively in patients with cervical radiculopathy due to cervical disc hernia before microendoscopic surgery. One patient with cervical radiculopathy due to cervical disc hernia before microendoscopic surgery and 5 healthy subjects underwent simultaneous apparent T2 mapping and neurography with SHINKEI-Quant.

View Article and Find Full Text PDF

Nodular fasciitis (NF) is a benign reactive proliferation of myofibroblasts that predominantly occurs subcutaneously. Commonly, it presents as a rapidly growing swelling in 4-8 weeks. NF mostly occurs in adults aged 20-50 years and usually has a diameter < 3-4 cm.

View Article and Find Full Text PDF

Autologous vein wrapping is used to treat recurrent chronic constriction neuropathy and traumatic peripheral nerve injury. However, its use is restricted due to the inability to obtain sufficiently long veins for larger grafts. We previously reported that vein-derived basic fibroblast growth factor (bFGF) promotes heme oxygenase-1 (HO-1), which reduces allodynia via its anti-inflammatory properties.

View Article and Find Full Text PDF

Although the therapeutic potential of vein wrapping (VW) for recurrent compressive neuropathy has been widely reported, the mechanisms underlying this technique have not been characterized. M2 macrophages induced by interleukin-4 (IL-4) or interleukin-10 (IL-10) have an anti-inflammatory function and play an important role in peripheral nerve repair. To evaluate whether VW promotes M2 polarization, we divided chronic constriction injury (CCI) rats into untreated and VW (CCI + VW)-treated groups.

View Article and Find Full Text PDF

The clinical efficacy of autologous vein wrapping for recurrent compressive neuropathy has been demonstrated; however, the underlying mechanisms of this technique remain unclear. Rats were divided into chronic constriction injury (CCI) and CCI + vein wrapping (CCI + VW) groups. Mechanical allodynia was evaluated using von Frey filaments.

View Article and Find Full Text PDF

Orthopedic trauma surgeons often encounter Smith's fracture in patients who report that they have fallen on the palms of their hands. The aim of this study was to clarify the pathogenesis of Smith's fracture in basic clinical aspects. First, a survey was conducted for investigating the mechanism of injury and arm position at the time of injury among patients with Smith's fractures who consulted at our outpatient clinic.

View Article and Find Full Text PDF

Study Design: Prospective trial of virtual endoscopy in spinal surgery.

Objective: To investigate the utility of virtual endoscopy of the spine in conjunction with spinal surgery.

Summary Of Background Data: Several studies have described clinical applications of virtual endoscopy to visualize the inside of the bronchi, paranasal sinus, stomach, small intestine, pancreatic duct, and bile duct, but, to date, no study has described the use of virtual endoscopy in the spine.

View Article and Find Full Text PDF