A double mobility acetabular implant for primary hip arthroplasty in patients at high risk of dislocation

IntroductionDislocation following total hip replacement continues to be a problem for which no completely satisfactory solution has been found. Several methods have been proposed to reduce the incidence of hip dislocations with varying degrees of success, including elevated rim liners, constrained liners and large diameter bearings. We present our experience with the double mobility acetabular component in patients at high risk of instability.MethodsThis was a retrospective review of 65 primary total hip arthroplasties in 55 patients (15 men, 40 women), performed between October 2005 and November 2009. The majority (80%) of patients had at least two and 26% had at least three risk factors for instability. The mean age was 76 years (range: 44–92 years). The patients were followed up for a mean duration of 60 months (range: 36–85 months).ResultsFourteen patients died and one was lost to follow-up, leaving fifty hips for final assessment. Until the final follow-up appointment, no patients had dislocation and none required revision surgery. The mean Oxford hip score improved from 45.0 to 26.5 (p<0.0001). The mean Merle d’Aubigné pain score improved from 1.4 to 4.9 (p<0.0001), the walking score from 2.3 to 3.1 (p<0.07) and the absolute hip function score from 5.4 to 10.8 (p<0.0001). There were no clinical or radiographic signs of loosening.ConclusionsThe double mobility acetabular component was successful at preventing dislocation during early to medium-term follow-up. However, as data are still lacking with regard to polyethylene wear rates at the additional bearing surface, it would be prudent to restrict the use of this implant to selected patients at high risk of instability.     

Implants,Mechanical Devices,and Vascular Surgery for Erectile Dysfunction

IntroductionThe field of erectile dysfunction (ED) is evolving and there is a need for state-of-the-art information in the area of treatment.AimTo develop an evidence-based, state-of-the-art consensus report on the treatment of erectile dysfunction by implants, mechanical devices, and vascular surgery.MethodsTo provide state-of-the-art knowledge concerning treatment of erectile dysfunction by implant, mechanical device, and vascular surgery, representing the opinions of 7 experts from 5 countries developed in a consensus process over a 2-year period.Main Outcome MeasureExpert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.ResultsThe inflatable penile prosthesis (IPP) is indicated for the treatment of organic erectile dysfunction after failure or rejection of other treatment options. Comparisons between the IPP and other forms of ED therapy generally reveal a higher satisfaction rate in men with ED who chose the prosthesis. Organic ED responds well to vacuum erection device (VED) therapy, especially among men with a suboptimal response to intracavernosal pharmacotherapy. After radical prostatectomy, VED therapy combined with phosphodiesterase type 5 therapy improved sexual satisfaction in patients dissatisfied with VED alone. Penile revascularization surgery seems most successful in young men with absence of venous leakage and isolated stenosis of the internal pudendal artery following perineal or pelvic trauma. Currently, surgery to limit venous leakage is not recommended.ConclusionsIt is important for the future of the field that patients be made aware of all treatment options for erectile dysfunction in order to make an informed decision. The treating physician should be aware of the patient's medical and sexual history in helping to guide the decision. More research is needed in the area of revascularization surgery, in particular, venous outflow surgery. Hellstrom WJG, Montague DK, Moncada I, Carson C, Minhas S, Faria G, and Krishnamurti S. Implants, mechanical devices, and vascular surgery for erectile dysfunction.     

The zinc finger DNA-binding domain of K-RBP plays an important role in regulating Kaposi's sarcoma-associated herpesvirus RTA-mediated gene expression

K-RBP is a KRAB-containing zinc finger protein with multiple zinc finger motifs and represses Kaposi's sarcoma-associated herpesvirus (KSHV) transactivator RTA-mediated transactivation of several viral lytic gene promoters, including the ORF57 promoter. Whether K-RBP binds DNA through its zinc fingers and the role of zinc finger domain in repressing gene expression are unclear. Here we report that K-RBP binds DNA through its zinc finger domain and the target DNA sequences contain high GC content. Furthermore, K-RBP binds to KSHV ORF57 promoter, which contains a GC-rich motif. K-RBP suppresses the basal ORF57 promoter activity as well as RTA-mediated activation. The zinc finger domain of K-RBP is sufficient for the suppression of ORF57 promoter activation mediated by the viral transactivator RTA. Finally, we show that K-RBP inhibits RTA binding to ORF57 promoter. These findings suggest that the DNA-binding activity of K-RBP plays an important role in repressing viral promoter activity.     

Neither lymphotoxin alpha nor lymphotoxin beta receptor expression is required for biogenesis of lymphoid aggregates or differentiation of natural killer cells in the pregnant mouse uterus

Gene ablation studies in mice indicate that lymphotoxin (LT)alpha, LTbeta and LTbetaR are essential for the genesis of lymph nodes (LN), normal structural development of peripheral lymphoid tissues and the differentiation of natural killer (NK) cells. LTbetaR binds to the heterotrimeric cytokines LTalpha1beta2 and LIGHT. LTs also regulate stromal cell expression of lymphocyte homing chemokines. Uterine decidualization in normal (+/+) mice is accompanied by the appearance and maturation of large numbers of uterine NK (uNK) cells that differentiate from precursors mobilized to the uterus from secondary lymphoid tissues. uNK cells accumulate in a transient, lymphocyte-rich region known as the metrial gland or, more recently, the mesometrial lymphoid aggregrate of pregnancy (MLAp). To determine if LTs contribute to development of the MLAp, and to the differentiation and/or localization of uNK cells, a histological study was undertaken of implantation sites from LTalpha null, LTbetaR null and gestation day-matched, normal mice. Implantation sites from the gene-ablated mice contained abundant numbers of uNK cells that localized appropriately. This indicates that the stromally derived molecules supporting NK cell differentiation in the uterus differ from those used in secondary lymphoid organs.     

Current concepts in the pharmacotherapy of benign prostatic hyperplasia

Benign prostatic hyperplasia is a major men's health issue, with approximately 80% of all men developing this condition within their lifetime. A variety of oral treatments is available, including alpha-adrenoceptor antagonists (alpha-blockers), 5alpha reductase inhibitors, aromatase inhibitors and phytotherapy. A large number of alpha-blockers can be administered, but no single agent has demonstrated a clear superiority over the other drugs. 5alpha Reductase inhibitors have demonstrated similar efficacy in larger volume prostates but most evidence suggests that there is no benefit in combining them with alpha-blockers. The use of phytotherapy is not entirely novel but requires further long-term evaluation before it can be endorsed for clinical use in benign prostatic hyperplasia.     

A retrospective review of pharyngeal pouch surgery in 56 patients

We retrospectively reviewed 56 consecutive patients treated surgically for a pharyngeal pouch at our institution between 1989-1999 (10 years). Various surgical procedures were performed including endoscopic stapling (20), external excision (23), Dohlman's procedure (9), pouch inversion (3), cricopharyngeal myotomy only (3), and pouch suspension (1). There were 12 patients (18%) with complications and one mortality (2%). Four patients (7%) had a recurrence with 2 requiring further surgery. Over the latter 3 years, endoscopic stapling has emerged as the primary procedure for pharyngeal pouch surgery in our unit; with the advantages of an earlier commencement of diet and earlier hospital discharge. However, results were not as good as for external excisions. Furthermore, there were difficulties with 3 cases that commenced as endoscopic stapling procedures but had to he converted to external excisions due to inaccessibility in one case and iatrogenic perforations in two cases. As with any new technique, problems may occur and a learning curve has been appreciated in our unit. Surgeons must he prepared, with informed consent, to convert to an external approach should difficulties arise during endoscopic stapling. Elderly and frail patients who are at risk from a general anaesthetic may benefit from endoscopic stapling. External excision of pharyngeal pouches may be more appropriate in the young, the medically fit, and when malignancy is a concern.