Tranexamic acid reduces blood loss and blood transfusion after TKA: a prospective randomized controlled trial

Background  

TKA may be associated with considerable blood loss, and transfusion carries substantial risk of immunologic reaction and disease transmission. Blood transfusion also involves additional cost, therefore a reduction in its use is important. Several methods reportedly reduce postoperative blood loss and avoid homologous blood transfusion with traditional TKA approaches, but it is unclear these reductions apply to a minimally invasive technique.     

Medial proximal tibial angle after medial opening wedge HTO: A retrospective diagnostic test study

Background:

Medial proximal tibial angle (MPTA) is the commonly used angle, which is simply measured from the knee radiographs. It can determine the correction angle in medial opening wedge high tibial osteotomy (MOWHTO). The hypothesis of our study is that post-osteotomy MPTA can predict the change in correction angle, and we aimed to determine the optimal MPTA with which to prevent recurrent varus deformity after MOWHTO.

Materials and Methods:

Between January 2002 and April 2010, radiographs of 59 patients, who underwent 71 MOWHTOs using the locking-compression osteotomy plates without bone grafts, were evaluated for the change of the MPTA. The MPTA was measured preoperatively and one and twelve months postoperatively. The changes of MPTA between one and twelve months were classified into valgus, stable, and varus change. The predicting factors were analyzed using analysis of variance (ANOVA) and Bonferroni multiple comparisons. The receiver operating characteristic (ROC) curve was used to find out the cut off point for preventing the recurrent varus deformity.

Results:

The overall preoperative, and one and twelve month postoperative MPTA values were 84.4 ± 2.4°, 97.2 ± 4.1°, and 96.3 ± 3.6°, respectively. Between one and twelve months, 39 knees displayed reduced varus change (–2.8 ± 2.1°), 18 knees displayed no change, and 14 knees displayed a greater valgus change (+2.9 ± 2.1°). The best factor for predicting these changes was the one month MPTA value (P = 0.006). By using the ROC curve, a one month MPTA of 95° was analyzed as the cut off point for preventing the recurrent varus deformity. With MPTA ≥95°, 92.3% of the osteotomies exhibited stable or varus change and 7.7% exhibited valgus change. However, with MPTA <95°, 47.4% exhibited stable or varus change and 52.6% exhibited valgus change (P < 0.001, odds ratio = 13.3).

Conclusion:

The postoperative MPTA can be used to predict the change in correction angle and an MPTA of at least 95° is the crucial angle with which to prevent recurrent varus deformity.     

Transarterial embolization for the treatment of massive bleeding in gynecologic and obstetric emergencies: a single center experience

Delayed treatment of the massive bleeding in gynecologic and obstetric conditions can cause high morbidity and mortality. The aim of this study is to assess the angiographic findings and outcomes of transarterial embolization in cases of massive hemorrhage from underlying gynecological and obstetrical conditions. This is a retrospective study of 18 consecutive patients who underwent transarterial embolization of uterine and/or hypogastric arteries due to massive bleeding from gynecological and obstetrical causes from January 2006 to December 2011. The underlying causes of bleeding, angiographic findings, technical success rates, clinical success rates, and complications were evaluated. Massive gynecological and obstetrical bleeding occurred in 12 cases and 6 cases, respectively. Gestational trophoblastic disease was the most common cause of gynecological bleeding. The most common cause of obstetrical hemorrhage was primary post-partum hemorrhage. Tumor stain was the most frequent angiographic finding (11 cases) in the gynecological bleeding group. The most common angiographic findings in obstetrical patients were extravasation (2 cases) and pseudoaneurysm (2 cases). Technical and final clinical success rates were found in all 18 cases and 16 cases. Collateral arterial supply, severe metritis, and unidentified cervical laceration were causes of uncontrolled bleeding. Only minor complications occurred, which included pelvic pain and groin hematoma. Percutaneous transarterial embolization is a highly effective and safe treatment to control massive bleeding in gynecologic and obstetric emergencies.     

Compacted cancellous bone has a spring-back effect

A new surgical technique, compaction, has been shown to improve implant fixation. It has been speculated that the enhanced implant fixation with compaction could be due to a spring-back effect of compacted bone. However, such an effect has yet to be shown. Therefore we investigated in a canine model whether implant cavities prepared with compaction had spring back. Before killing the animals, we used one of two surgical techniques to make implant cavities of identical dimensions in both lateral femoral condyles of 7 dogs. One side had the implant cavity prepared with compaction, the other side with drilling. The cavities were left empty in vivo for 10 minutes before the dogs were killed. Postoperative micro-CT scanning showed that the diameters of the compacted cavities were significantly smaller than those of the drilled cavities, although they had had identical dimensions initially. Thus we found a spring-back effect of compacted bone, which may be important for increasing implant fixation by reducing initial gaps between the implant and bone.     

Congenital Hepatic Arteriovenous Malformation Presenting with Severe Persistent Pulmonary Hypertension

Congenital hepatic arteriovenous malformation is a rarely seen vascular malformation with persistent pulmonary hypertension in neonates. The authors report a full-term female newborn presenting with intractable heart failure and respiratory distress soon after birth. Investigation by echocardiography showed severe persistent pulmonary hypertension of the newborn and patent ductus arteriosus. The hepatic angiogram revealed congenital hepatic arteriovenous malformation; therefore, secondary pulmonary artery hypertension complicated with ‘steal’ phenomenon was conclusively diagnosed.