Quantitative analysis of glycosaminoglycans, chondroitin/dermatan sulfate, hyaluronic acid, heparan sulfate, and keratan sulfate by liquid chromatography-electrospray ionization-tandem mass spectrometry.

We developed a method using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode for simultaneous quantitative analysis of glycosaminoglycans (GAGs). Using one-shot analysis with our MS/MS method, we demonstrated the simultaneous quantification of a total of 23 variously sulfated disaccharides of four GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 12 heparan sulfates, and 2 keratan sulfates) with a sensitivity of less than 0.5 pmol within 20 min.

Bone screws have advantages in repair of experimental osteochondral fragments.

Background: Cartilage defects are created on intraarticular osteochondral fragments at the entrance holes of fixation devices when these fragments are fixed to the original sites. Conventional fixation devices hinder repair of these defects and there is a latent risk of secondary osteoarthritis. We therefore developed a novel fixation device system consisting of bone screws made of cortical bone for osteochondral fragments to improve repair of these surface defects.

Mortality in patients with hip fracture aged over 90 years: a report from a progressively aging island.

Introduction: In our aging society, hip fractures are common in elderly patients, especially those aged above 90 years. Improving mortality rates after this injury is an important part of medical management for the elderly. This study assessed mortality rates after hip fracture in patients aged ≥90 years and examined factors that contribute to mortality.

Postoperative antimicrobial prophylaxis following spinal decompression surgery: is it necessary?

Background: Antimicrobial prophylaxis (AMP) can reduce the risk of surgical-site infection (SSI) following many types of surgery, particularly spinal surgery. After publication of the Guideline for Prevention of Surgical Site Infection by the Centers for Disease Control and Prevention in 1999, a large number of studies confirmed the effectiveness of AMP. However, because the concept of AMP is not clear in Japan, the duration of postoperative AMP tends to be long.

A case of symptomatic tumoral calcinosis on the great toe and review of the literature.

A 67-year-old woman with no specific medical history showed a hard mass on her great toe for several years. The lesion was elastic, round, and had good mobility. An X-ray showed the lesion to be a calcified "chicken wire" lesion; CT and MRI findings indicated it as a benign subcutaneous calcified tumor.

Retrograde drilling for osteochondral lesions of the talar dome.

Background: For the treatment of osteochondral lesions of the talar dome without detachment of the cartilage, there is little information on whether transmalleolar drilling or retrograde drilling is more effective in terms of clinical and morphologic evaluations.

Hypothesis: Retrograde drilling may be more effective than transmalleolar drilling for lesions without cartilage detachment.

Study Design: Case control study; Level of evidence, 3.