The effects of femoral component design on the patello-femoral joint in a PS total knee arthroplasty

Introduction

Anterior knee pain following TKA performed utilizing the PFC Sigma system still represents a cause of failure. The purpose of this study was to evaluate whether or not a recent change in the femoral design (PFC Sigma PS) had a positive impact on the patello-femoral complication rate.

Materials and methods

A consecutive series of 100 TKA using the PFC Sigma PS system was followed prospectively for a minimum of 3 years. All patellae were replaced and a standard lateral release was never performed. Radiographic analysis following the Knee Society Score (KSS) included antero-posterior weight-bearing, lateral and bilateral axial radiographs. TKA rotational alignment was recorded at the final follow-up in 30 consecutive knees by performing a CT evaluation.

Results

Good to excellent clinical results according to the KSS were achieved in 94 % of the knees. Survival without need of reoperation for any reason was 98 % at 3 years minimum follow-up; two reoperations were done for removal of fibromatous intra-articular tissue (“Clunk syndrome”). There were no revisions for septic or aseptic loosening of the components. The mean ROM improved from 104° preoperatively to 115° (97°–132°) postoperatively: postoperative flexion was 120° or more in 58 % of the knees. Severe anterior knee pain was present in 9 % of patients. Radiographic evaluation showed 90 knees with a tibio-femoral anatomical axis between 8° and 2° of valgus (±3° from the intraoperative goal). CT evaluation of 30 consecutive knees showed that the femoral component positioning in relationship to the trans-epicondylar axis had only 2.80° of external rotation (±2.10°) with respect to a planned external rotation of 3°. This difference was statistically significant.

Conclusions

Although the PFC Sigma PS system provides good and predictable results for tricompartmental arthritis of the knee, anterior mechanism complications still represent a reason for dissatisfaction in a substantial group of patients.     

Unusual presentation of intradural endodermal cysts in young children under 2 years of age. Report of two cases

Introduction Spinal endodermal cysts are congenital maldevelopmental lesions usually presenting in early adulthood. Whereas the diagnosis is rare in newborns and it is usually led by cardiopulmonary distress or other associated malformations, no characteristic clinical findings associated with these entities have been described in older patients where spinal endodermal cysts usually behave as intraspinal space occupying lesions. Discussion The authors report on two children under 2 years of age affected by cervical endodermal cysts that presented with a history of acute motor deficit following a laryngitis. The hypothesis about the pathogenesis is that the upper respiratory tract infection might have stimulated the secretion of the cyst lining, inducing growth of the cyst and the sudden appearance of the motor deficit. Because of the apparent lack of relation between the benign laryngitis and the motor deficit, the occurrence of such an association might have been underestimated in some of the previously reported cases.     

Incidence of bacteremias and invasive mycoses in children with acute non‐lymphoblastic leukemia: Results from a multi‐center Italian study

Background

Data on the epidemiology of bacteremias and invasive fungal diseases (IFD) in children with acute myeloid leukemia (AML) are scarce.

Design and Methods

In a multi‐center, retrospective study, we analyzed proportion, rate per 1,000 person‐days at risk, and cumulative risk of bacteremias and IFD in children with AML.

Results

Between January 1998 and December 2005, 240 children were treated for AML at 8 Italian Centers, for a total of 521 treatment courses and 63,232 person‐days at risk. Bacteremia was observed in 32% of treatment courses and IFD was seen in 10% (P < 0.0001), with rates of 2.62 and 0.84, respectively (P < 0.001). There was a significantly higher frequency of IFD during relapse treatment: proportion 15% versus 9% (P = 0.05), rate 2.10 versus 0.64 (P = 0.008) and cumulative risk 32% versus 12% (P = 0.007), while there were no differences in the proportion, rate and cumulative risk of bacteremia during front‐line or relapse treatment. The epidemiology of bacteremias and IFD was different during front‐line therapy for M3 as compared to other types of AML, but the differences were not statistically significant.

Conclusions

Severe infectious complications are frequent during the treatment of pediatric AML, especially during relapse treatment, and bacteremias are more frequent than IFD. Pediatr Blood Cancer. 2010;55:1103–1107. © 2010 Wiley‐Liss, Inc.

     

Heparin/heparan sulfate anticoagulant glycosaminoglycans in human plasma of healthy donors: preliminary study on a small group of recruits

Glycosaminoglycans in normal human plasma, mainly represented by chondroitin sulfates and heparan sulfates/heparin (HSGAGs), show a specific distribution in the Cohn-Oncley fractions of human plasma. In the present study we investigated their effects on coagulation. Plasma was fractionated following the procedure of Cohn-Oncley, and each fraction was treated for extraction of glycosaminoglycans after extensive proteolysis; the anticoagulant activity in the extracted samples was measured by activated partial thromboplastin time (APTT). The effects of the samples containing HSGAGs on factor II and factor X activities, before and after treatment with heparinase I, were also measured. The molecular weight of HSGAGs was determined by polyacrylamide gel-electrophoresis. Cryoprecipitate and fraction I, fraction II+III, and fraction IV-1 (the fractions containing HSGAGs) prolonged the APTT, whereas fractions IV-4 and V had no effect on the APTT. Fractions containing HSGAGs showed effects on factor II and factor X activities that were sensitive to heparinase I treatment. The molecular weight of HSGAGs recovered in cryoprecipitate and fraction I was 15-18 kDa; that of HSGAGs recovered in fraction IV-1 was 12.0 kDa. In conclusion, these results demonstrate that HSGAGs of different molecular weight, endowed with anticoagulant activity, circulate in normal human plasma in association with specific proteins involved in the regulation of hemostasis; and that endogenous HSGAGs play a role in maintaining the antithrombotic/hemostatic balance in normal human plasma.     

Gd-BOPTA/Dimeg: experimental disease imaging.

The novel tissue-specific contrast agent, Gd-BOPTA/Dimeg, was tested in MR imaging of experimental focal liver disease and of acute myocardial ischemia in rats. Directly implanted liver tumors and blood-borne metastases were used as models for focal liver disease and occlusion of the lower anterior descending coronary artery as model for acute ischemia. The studies with implanted tumors, at a dose level of 250 mumol/kg, showed a very high (370%) and persistent (greater than 2 h) increase in the tumor-liver contrast-to-noise ratio (CNR), owing to selective enhancement of normal liver parenchyma signal intensity. While all blood-borne metastases showed a similar late CNR enhancement, some of them experienced early contrast loss due to transient signal intensity enhancement. In myocardial imaging, Gd-BOPTA/Dimeg produced a signal intensity enhancement in normal myocardium and an injured area-normal area CNR enhancement which were both much stronger and more persistent than those produced by Gd-DTPA/Dimeg.