Kazushige Maeda

Ultrasonographic measurement of humeral torsion

This article presents a new method for the measurement of humeral torsion with the use of ultrasonography and discusses clinical applications of the method such as the evaluation of cubitus varus deformity after a supracondylar elbow fracture. Torsion angle increased 14 degrees from the time the patients were newborns to when they were adults. No significant difference was found between the right and left sides in healthy subjects. When humeral shaft or supracondylar fractures are treated, or when rotational deformities of the humerus are corrected, this method of measurement is very practical, because the humeral torsion of the unaffected side provides a standard for the individual. With this method of measuring humeral torsion, we also found that cubitus varus deformity after supracondylar fracture in children is caused not only by an increase in varus angulation but also by internal rotation of the distal fragment.

IgG-class anti-PF4/heparin antibodies and symptomatic DVT in orthopedic surgery patients receiving different anti-thromboembolic prophylaxis therapeutics

BackgroundHeparin-induced thrombocytopenia (HIT) is a thromboembolic complication that can occur with unfractionated heparin (UFH) or low molecular weight heparin (LMWH). Our objective was to determine and compare the incidence of IgG-class HIT antibodies in patients undergoing total hip arthroplasty (THA) or total knee arthroplasty (TKA) with different antithrombotic prophylaxis therapies and their contributions to the occurrence of venous thromboembolism (VTE).MethodsA prospective observational study was performed for 374 Japanese patients undergoing THA or TKA to determine the incidence of VTE. IgG-class anti-PF4/heparin antibodies were measured using IgG-specific EIA before and after the operation.ResultsIn the clinical outcome, the incidence of symptomatic deep vein thrombosis (DVT) was 15.0% (56/374, TKA; 35, THA; 21) and pulmonary emboli (PE) were not observed. The total seroconversion incidence of IgG-class PF4/heparin antibodies was 19.8% (74/374). The seroconversion incidence of IgG-class PF4/heparin antibodies was higher in patients receiving UFH (32.7%) compared to those receiving LMWH (9.5%) or fondaparinux (14.8%). Furthermore, the seroconversion incidence was significantly higher in patients undergoing TKA compared to those undergoing THA. Based on multivariate analysis, seroconversion of the IgG-class PF4/heparin antibodies was independent a risk factor for symptomatic DVT.ConclusionOur findings show that the seroconversion of IgG-class anti-PF4/heparin antibodies differed with various anti-thrombotic prophylaxis therapeutics and was associated with the risk of DVT in a subset of patients undergoing total joint arthroplasty (TKA and THA).

Successful treatment of refractory cardiac tamponade due to rheumatoid arthritis using pericardial drainage.

Rheumatoid pericarditis occurs in patients with rheumatoid arthritis (RA). However, cardiac tamponade due to rheumatoid pericarditis is rare; we describe a case of a 72-year-old man with a 6-year history of rheumatoid arthritis who developed rheumatoid pericarditis with recurrent cardiac tamponade. The patient experienced relapse of the cardiac tamponade despite treatment with pericardiocentesis. Therefore, the patient underwent surgical pericardial drainage. The patient was also subsequently treated with increasing doses of corticosteroid, methotrexate and leukocytapheresis. These treatments resulted in a successful outcome without any complication. This case suggests that in addition to immunosuppressive therapy, pericardial drainage should be considered in the treatment of life-threatening refractory cardiac tamponade caused by rheumatoid arthritis.

Clinical relevance of heparin-PF4 complex antibody in DVT after total joint replacement

BackgroundAntibodies to the heparin-platelet factor-4 (HPF-4) complex (HIT antibodies) have been observed in patients with heparin-induced thrombocytopenia (HIT). These antibodies are thought to be involved in thrombosis through activation of platelet/endothelial cells. This prospective study was conducted to determine the incidence of post-operative HIT antibodies to assess the associated risk of deep vein thrombosis (DVT) in patients undergoing total knee arthroplasty (TKA) or total hip arthroplasty (THA).MethodsWe studied 104 patients who underwent unilateral primary TKA (n = 44) and primary THA (n = 60) with short-duration prophylaxis (1–2 days of a fixed dose of unfractionated heparin). HIT antibodies were assayed using a sandwich-type ELISA before the operation and after heparin treatment (post-operative day 7).ResultsIn the clinical outcome, the incidence of symptomatic DVT was 15.4% (16/104, TKA; 10, THA 6) and pulmonary embolism (PE) was not observed. The total seroconversion rate of HIT antibodies at post-operative day 7 was 34.6% (36/104). Among 36 seroconverted patients, 11 (30.6%) developed symptomatic DVT and 5 out of 68 of the non-seroconverted patients (7.4%) developed symptomatic DVT. The incidence for DVT was significantly higher in the seroconverted patients compared with that of the non-seroconverted patients (odds ratio 5.5, 95%CI: 1.7–17.6 p = 0.0028). Furthermore, in the patients with symptomatic DVT, the titer of HIT antibodies at post-operative day 7 was significantly higher compared with those without symptomatic DVT.ConclusionOur data therefore suggest that seroconversion for HIT antibodies generated by heparin is associated with a risk of DVT in patients undergoing total joint replacement.