Impingement testing of total hip replacements according to ASTM F2582 - Implant wear, resistance to damage and acceptance criteria.

OBJECTIVES: The aim of this study was to determine the resistance to impingement damage of three different artificially aged UHMWPE materials used for total hip joint replacement. The results obtained can be used as a basis for an acceptance criterion for testing according to ASTM F2582-20. METHODS: Three different polyethylene liner materials, standard polyethylene (UHMWPE), moderately crosslinked (XLPE) and vitamin E stabilized crosslinked (XLPE-VE) polyethylene of the same design and manufacturer were tested up to one million impingement cycles according to ASTM F2582-20. The liners were artificially oxygen aged for two and three weeks according to ASTM F2003-02. The wear volumes of the liner, acetabular shells, and hip endoprosthesis stems were determined. Each of the six impingement test groups consisted of three samples. For each test group, a reference group was subjected to the same conditioning and loading conditions but without impingement between the hip stem and the liner. The force needed to disassemble the liner from the acetabular shell (push-out force) was determined according to ASTM F1820-22 for the test and the reference groups. RESULTS: XLPE and XLPE-VE polyethylene groups showed less impingement wear when compared to the standard UHMWPE material. Similarly, the protective function of the liner against direct metal-on-metal contact was greater, resulting in less wear on the acetabular shell and the stem neck. The three weeks aged standard UHMWPE group showed early onset of fatigue delamination wear. The push-out values remained unchanged for all XLPE liners and the 3-week aged XLPE-VE liners. The aged UHMWPE liners showed low push-out strength due to component shrinkage caused by aging in combination with the tapered fixation used for this specific design. SIGNIFICANCE: The largest polyethylene wear volume measured of XLPE and XLPE-VE polyethylene aged for two and three weeks was 15.05 mm³ (SD 0.56 mm³). The corresponding metal wear volume was 1.23 mm³ (SD 0.19 mm³) for the acetabular cup and 1.33 mm³ (SD 0.20 mm³) for the stem neck. Those values can support the definition of an acceptance criteria for impingement testing. The results of the push-out test required by ASTM F2582-20 should be evaluated with respect to geometry changes caused by aging. The protective effect of the polyethylene liner against metal-on-metal contact should be considered in the implant design phase in order to avoid implant failure due to metal debris.

[Testicular sperm extraction in male infertility : Indications, success rates, practical implementation, and possible complications]. / Testikuläre Spermienextraktion bei männlicher Infertilität : Indikationen, Erfolgsraten, praktische Durchführung und mögliche Komplikationen.

BACKGROUND: Unwanted childlessness is a burden on a couple's relationship. The therapeutic spectrum of male infertility has increased significantly in recent years so that even azoospermia patients can be given biological paternity by testicular sperm extraction (TESE). OBJECTIVES: The indications, success rates, practical implementation, and possible complications of conventional and microscopic TESE in male infertility are presented in this review. METHODS: A nonsystematic search of the relevant literature was carried out. RESULTS: In obstructive azoospermia (OA), primarily desobstructive surgical procedures are used, while TESE is the surgical procedure of choice in nonobstructive azoospermia (NOA). In the latter, sperm extraction can be performed conventionally or microscopically (mTESE) assisted, whereby the latter offers an advantage in terms of sperm detection rate in the case of small testicular volumes (<12 ml), chemotherapy, Klinefelter's disease and AZFc microdeletions. The sperm detection rate of TESE is about 50%. Postoperative controls are useful because of the possible induction of symptomatic hypogonadism. CONCLUSION: Before performing TESE, determining the hormone status and human genetic clarification are necessary. Any costs incurred and the possibility of missing sperm proof must be discussed. Close cooperation between andrologists, gynecologists, reproductive physicians, and human geneticists is necessary. All in all, TESE is a safe surgical procedure with a low complication rate.

[Does structural and process quality of certified prostate cancer centers result in better medical care?] / Resultiert aus Struktur- und Prozessqualität zertifizierter Prostatakarzinomzentren eine bessere medizinische Versorgung?

BACKGROUND: An improved structural and process quality could be demonstrated 13 years after certification of the first German prostate cancer center. The question of optimization of the functional quality by establishing organ cancer centers arises. OBJECTIVE: A critical benefit-risk analysis of organ cancer centers was carried out to evaluate an improved quality of results. MATERIAL AND METHODS: Based on published results from individual centers and the individual annual reports of the German Cancer Society (DKG), the data for evaluating the quality of results were checked. For the issuing of certificates, the focus is on quality indicators for oncological surgery. The functional quality of results is assessed exclusively by a questionnaire-based survey. RESULTS: An improvement in the quality of functional results after radical prostatectomy has not yet been demonstrated. The functional quality features of urinary continence and erectile function that are essential for the quality of life and patient satisfaction are only insufficiently assessed due to the lack of objective measuring instruments and are not relevant for certification. There is no reliable evidence for improved overall survival, reduction in tumor-specific mortality, and optimization of functional results in certified centers. CONCLUSION: The relationship between certification and excellence cannot be proven without individual consideration of a surgeon-specific pentafecta analysis. For this reason, certification-relevant surgeon-related quality assurance is recommended.

Vesico-urethral anastomotic stenosis following radical prostatectomy: a multi-institutional outcome analysis with a focus on endoscopic approach, surgical sequence, and the impact of radiation therapy.

OBJECTIVES: To investigate the predictors of recurrence and of de novo incontinence in patients treated by transurethral incision or resection for vesico-urethral anastomotic stenosis (VUAS) after radical prostatectomy. MATERIAL AND METHODS: All patients undergoing endoscopic treatment for VUAS between March 2009 and October 2016 were identified in our multi-institutional database. Digital chart reviews were performed and patients contacted for follow-up. Recurrence was defined as any need for further instrumentation or surgery, and de-novo-incontinence as patient-reported outcome. RESULTS: Of 103 patients undergoing endoscopic VUAS treatment, 67 (65%) underwent transurethral resection (TR) and 36 (35%) transurethral incision (TI). TI was performed more frequently as primary treatment compared to TR (58% vs. 37%; p = 0.041). Primary and repeated treatment was performed in 46 (45%) and 57 patients (55%), respectively. Overall, 38 patients (37%) had a history of radiation therapy. There was no difference in time to recurrence for primary vs repeat VUAS treatment, previous vs no radiation, TR compared to TI (all p > 0.08). Regarding treatment success, no difference was found for primary vs. repeat VUAS treatment (50% vs. 37%), previous radiation vs. no radiation (42% vs. 43%), and TR vs. TI (37% vs. 53%; all p ≥ 0.1). Postoperative de novo incontinence was more common after TI vs. TR (31% vs. 12%; p = 0.032), no difference was observed for previous radiation therapy vs. no radiation therapy (18% vs. 18%; p > 0.9) or primary vs. repeat VUAS treatment (22% vs. 16%; p = 0.5). CONCLUSION: VUAS recurrence after endoscopic treatment is not predictable. Endoscopic treatment with TI showed a higher risk for de novo incontinence than TR, and previous irradiation and the number of treatments do not influence incontinence.

[Penile paraffinoma-Treatment strategies]. / Penile Paraffinome ­ therapeutische Strategien.

BACKGROUND: Penile paraffinomas are a consequence of an injection of mineral oils for augmentation. As an result of the foreign body reaction local complications regularly occur, which require a plastic reconstructive intervention. So far 8 cases have been treated in our clinic over the last 20 years. OBJECTIVE: Presentation of the operative treatment techniques for penile paraffinoma as well as the indications and complications. MATERIAL AND METHODS: After reviewing the relevant literature, we analyzed the data of our own patient cohort. Since 1999 a total of 8 patients with lipogranuloma underwent surgical treatment at the St. Antonius Hospital in Eschweiler. RESULTS: The choice of a plastic reconstructive treatment depends on the extent of the paraffinoma. If it is limited to the foreskin, a radical circumcision is sufficient but if it extends to the skin of the penile shaft, a plastic defect coverage with a mesh graft, a full skin graft or a scrotal skin flap is required. In cases with additional pathologies, such as urethral fistulas, auxiliary reconstructive procedures should be performed. CONCLUSION: For optimal cosmetic and functional results, the surgeon must master a broad spectrum of plastic reconstructive techniques. In selected complex cases an interdisciplinary approach consisting of urologists and plastic surgeons can be necessary.

[Vascular injuries during urologic surgery]. / Gefäßverletzungen während urologischer Operationen.

This review article summarizes the epidemiology of vascular injuries during urologic surgery and discusses intraoperative strategies to control bleedings. Techniques of vascular approaches (arteries and veins) are discussed and tricks for vascular repair are explained. Generally, vascular injuries during urologic surgery are rare. However, hemorrhage due to vascular injury is a common cause of critical morbidity and mortality in the perioperative period. Susceptibility to vascular complications such as oncological debulking and revision surgery increase risk for damage. As vascular injuries range from arrosion to avulsion, treatment is also broad, ranging from vascular suture to open or endovascular repair. Prevention of exsanguination requires visual control to stop the bleeding. The surgeon must act quickly to initiate appropriate repair, aiming for damage control and stabilization of the patient. Planning the surgery and consulting an experienced surgeon are decisive for successful management. Catastrophic bleeding has to be controlled and in the case of arterial injury it is often necessary to reconstitute perfusion. Reconstructions such as vascular anastomoses, patch angioplasty or interposition grafts are the preferred surgical techniques which are influenced by the nature of the injury. Vessels have to be thoroughly prepared before cross clamping to prevent injury by vascular clamps. Veins can often be ligated. Endovascular repair is also a possibility to control the bleeding, but nowadays it is often a definitive therapy method. For example, resuscitative endovascular balloon occlusion is useful to stabilize the patient and then to initiate vascular repair. Depending on the type of surgery performed, different vessels are concerned. Severe bleeding is usually located retroperitoneal affecting the aorta, renovisceral and iliac vessels. Predisposing urologic operations are lymphadenectomy, nephrectomy and (cysto)prostatectomy and also the laparoscopic approach can cause bleeding complications.

[Knowledge and early detection of testicular germ cell cancer among adolescents and young adults]. / Kenntnisstand und Früherkennung maligner Keimzelltumoren des Hodens unter Jugendlichen und jungen Erwachsenen.

INTRODUCTION: Malignant testicular germ cell tumors are the most common tumor disease in young men, affecting not only the period of his reproductive phase but also creating a complex life situation. Therapy includes the risk of development of second neoplasia and sequelae. However, particularly in this age group, knowledge about this disease and risk factors is sparse, and preventive examinations are not available or are not or insufficiently used. MATERIALS AND METHODS: In order to evaluate the state of knowledge on testicular tumors in adolescents, a knowledge survey was conducted at 6 high schools in Hamburg from January to April 2019 among pupils of grades 11 and 12. This was carried out with a questionnaire comprising 15 items, which was analyzed and also evaluated on a gender-specific basis. Only fully completed questionnaires were considered. RESULTS: The overall proportion of correctly answered questions was 60.04%. Broken down by gender, the proportion was 60.18% for female pupils and 59.14% for male pupils, while the gender ratio was 52.2 and 47.8% for female pupils. Special questions on testicular tumors were answered correctly by 59.71% of the female students and 54.8% of the male students, while general questions on the structure and function of the male sexual organs were answered 4.51% better by the male students with 64.9%. These were statistically significant in both cases. CONCLUSION: The survey shows a gender-specific knowledge deficit on testicular tumors, which is more pronounced among boys. As intensified knowledge transfer on this topic alone is insufficient, a preventive examination should be established especially for boys. This would enable individual, risk-commensurate and needs-adapted monitoring and early detection of testicular tumor disease, but also of other health issues in male adolescents.

[Surgical urinary diversion in children from war and crisis areas-20-year experience report]. / Operative Harnableitung bei Kindern aus Kriegs- und Krisengebieten ­ 20-jähriger Erfahrungsbericht.

BACKGROUND: Because sick and injured children from war and crisis areas can often only be helped to a limited extent in their countries of origin, those children with the most complex diseases often receive medical treatment in Europe. MATERIALS AND METHODS: To evaluate the postoperative outcome of reconstructive interventions in children from war and crisis areas, an evaluation of the clinic's internal database between 1997 and 2017 was carried out. The operative indication, the surgical procedure, any revisions or conversions and the overall mortality were analyzed. RESULTS: During the above-mentioned period a total of 44 (male: 32, female: 12) children aged 3-14 years from Afghanistan, Angola, Central Asia and the Caucasus were treated. Indications for the reconstructive procedures were bladder exstrophy (n = 23), neurogenic bladder dysfunction (n = 9), penile partial amputation (n = 1) and traumatic bladder dysfunction (n = 11). In 26 children, a conduit was created, 11 children received a sigma rectum pouch and 1 child an ileocecal pouch, while 5 other children received bladder augmentation and 1 child an oral mucosal urethroplasty. In total, 7 revisions or conversions due to ureteral implantation stenoses and recurrent acidosis had to be performed. Five children died in their home country due to acidosis, sepsis, end stage renal failure, accident and social exclusion. CONCLUSION: In the long term 39 of the 44 (88.6%) children live socially integrated in their home country and are regularly monitored by local aid organizations. When choosing the reconstructive intervention, the local conditions must be considered.

[Boys' health survey-between gender gap and information backlog]. / Wissenserhebung zum Thema Jungengesundheit ­ zwischen Geschlechterkluft und Nachholbedarf.

BACKGROUND: Early detection examinations take place from birth to the age of 6 years. The youth screening is a continuation of the screening of the "U-series" and should be carried out between the age of 12-15 and 16-17, respectively. Afterwards adolescent girls have good contact with a gynecologist, but adolescent boys usually do not have a medical contact person who they can trust in. MATERIALS AND METHODS: To evaluate the state of knowledge on boys' health, a 15-item comprehensive knowledge survey was conducted among ninth grade students at 7 secondary schools (Gymnasien) in North Rhine-Westphalia. The knowledge survey took place at three specified times (before, immediately after and approximately 3 months after adolescent sexual education classes). Only completed questionnaires were analyzed and evaluated in a gender-specific manner. RESULTS: Overall, 459 students participated from March-September 2017. Before sexual education instruction, about half of all questions were answered correctly by the students. Immediately after class, the proportion increased by a factor of 1.5 to a total of 79.24%. Then 2-3 months after the class, the percentage was 69.67%. Considering gender separately, this resulted in an increase of 15.32% for the female students and 16.99% for the male students. CONCLUSION: The knowledge survey reveals a need to catch up on facts on the subject of boys' health. Despite evidence of an increase in knowledge of both sexes after sexual education instruction, there is a gender gap. Hence, a preventive check-up especially for boys should be established and offered. Issues such as the prevention of sexually transmitted diseases, options for vaccination against human papillomavirus, etc. should be actively addressed.

[Urethral centralization and pseudo-glans formation after partial penectomy]. / Zentralisierung der Harnröhre und Pseudoglansbildung nach partieller Penektomie.

The management of penile cancer has altered dramatically over the last decade. Confidence to excise lesions safely with smaller margins has led to the adoption of penile-preserving techniques and in turn improved the functional and cosmetic results. Patients undergoing partial penectomy (PP) find that the urethral meatus is located in an abnormal ventral position. In addition, there is a high risk of meatal stenosis. We describe our novel technique that allows the urethral meatus to be centralised after PP and creation of a pseudo-glans and wide meatus and therefore maintain the cosmetic appearance of the penis after split thickness skin grafting. The UCAPP technique allows the restoration of the normal meatal location and creation of a pseudo-glans in case of partial penectomy and therefore can improve the overall cosmetic appearance and reduce the psychological morbidity.

[Patio repair for urethrocutaneous fistulae : Results of a multicentre retrospective study]. / PATIO-Repair zum Harnröhrenfistelverschluss : Ergebnisse einer multizentrischen, retrospektiven Studie.

BACKGROUND: Urethrocutaneous (UC) fistulae are common complications after hypospadias surgery and they have been a serious problem for surgeons since the repair was first attempted. We present the results of our multicentre retrospective study for repairing UC fistulae using the Patio ("preserve the tract and turn it inside out") repair described by Malone. MATERIALS AND METHODS: A total of 16 boys (Eschweiler 2, Lingen 4, Reading 10) at the ages of 1-10 years were treated for UC fistulae. Instead of excising the fistula tract, it is preserved and turned inside out, this creates a flap valve inside the urethral lumen. After a circumferential incision around the skin and meticulous dissection of the fistula tract, a 2/0 nylon suture is passed down the tract and brought out through the external urinary meatus. As a result, the fistula tract is inserted into the urethral lumen. In order to keep the fistula tract inverted, it is sutured to the tip of the external urinary meatus, or fixed by an angler lead (modification from Lingen). Due to the narrow base, the excess tissue atrophies postoperatively and leads to an appealing cosmetic result. RESULTS: A total of 9 fistula repairs were performed on an outpatient basis without using a transurethral catheter; 7 boys were treated on an inpatient basis with an average length of stay in the hospital for 1-2 days with/without catheterization. During a mean follow-up of up to 4.5 years, only one fistula recurrence occurred; no other complications were observed. CONCLUSION: The Patio repair for urethrocutaneous fistula is an outpatient, simply reproducible surgical technique without the necessity of transurethral catheterization. The short-term results are impressive; long-term results of a larger patient cohort will follow.