João Norberto Stavale

Bio: João Norberto Stavale is an academic researcher. The author has contributed to research in topics: Transverse fascia & Hernia. The author has an hindex of 1, co-authored 1 publications receiving 38 citations.

Quantitative and qualitative analysis of collagen types in the fascia transversalis of inguinal hernia patients.

Abstract: BACKGROUND: Inguinal hernia is the second most common surgical case in our field. The anatomical factors alone are not enough to explain the inguinal hernia. Studies show changes in the proportion and quantity of collagen fibers in the developing of inguinal hernia. The greater production of collagen type III compared to the type I could justify the thinning of the fascia transversalis and its weakness. AIM: To determine the quantitative and qualitative changes of collagen in the fascia transversalis in inguinal hernia patients and compare them to findings from corpses without inguinal hernia. METHOD: Prospective case-control study based on the biopsy of fascia transversalis of 27 patients and 24 corpses. The technique used was hematoxylin-eosin and picrosirius colorimetry. RESULTS: The medium percent area of collagen (types I + III) and collagen type I, in both groups, show no statistic difference. The quantity of collagen type III was greater in the patients. Patients classified with Nyhus IIIa presented greater quantity of collagen type III. CONCLUSION: There is no significant difference in the quantity of collagen in the fascia transversalis of patients compared to the controls. An increase in the quantity of collagen type III was found in patients with inguinal hernia and a greater quantity in those patients classified with Nyhus IIIa.

Connective tissue alteration in abdominal wall hernia

Abstract: Background: The aetiology and pathogenesis of abdominal wall hernia formation is complex. Optimal treatment of hernias depends on a full understanding of the pathophysiological mechanisms involved in their formation. The aim of this study was to review the literature on specific collagen alterations in abdominal wall hernia formation. Methods: A computer-assisted search of the medical databases PubMed and Embase was performed, together with a cross-reference search of eligible papers. Results: Fifty-two papers were included. Collagen alteration depended on the type of hernia; there were more pronounced changes in patients with a direct inguinal hernia than in those with an indirect inguinal hernia, recurrent inguinal hernia or incisional hernia. A consistent finding was a significant increase in immature type III collagen relative to the stronger type I collagen in patients with a hernia. This resulted in thinner collagen fibres with a correspondingly diminished biomechanical strength. It has been suggested that these alterations are due to variation in the synthesis, maturation or degradation of collagen by matrix metalloproteinases, in combination or alone. Conclusion: Hernia formation and recurrence is associated with altered collagen metabolism manifested by a decreased type I:III collagen ratio. Copyright © 2010 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

Pelvic organ prolapse and collagen-associated disorders

Abstract: Introduction and hypothesis Pelvic organ prolapse (POP) and other disorders, such as varicose veins and joint hypermobility, have been associated with changes in collagen strength and metabolism. We hypothesized that these various disorders were more prevalent in both POP patients and their family members.

Etiology of Inguinal Hernias: A Comprehensive Review

Abstract: Background The etiology of inguinal hernias remains uncertain even though the lifetime risk of developing an inguinal hernia is 27% for men and 3% for women The aim was to summarize the evidence on hernia etiology, with focus on differences between lateral and medial hernias Results Lateral and medial hernias seem to have common as well as different etiologies A patent processus vaginalis and increased cumulative mechanical exposure are risk factors for lateral hernias Patients with medial hernias seem to have a more profoundly altered connective tissue architecture and homeostasis compared with patients with lateral hernias However, connective tissue alteration may play a role in development of both subtypes Inguinal hernias have a hereditary component with a complex inheritance pattern, and inguinal hernia susceptible genes have been identified that also are involved in connective tissue homeostasis Conclusion The etiology of lateral and medial hernias are at least partly different, but the final explanations are still lacking on certain areas Further investigations of inguinal hernia genes may explain the altered connective tissue observed in patients with inguinal hernias The precise mechanisms why processus vaginalis fails to obliterate in certain patients should also be clarified Not all patients with a patent processus vaginalis develop a lateral hernia, but increased intraabdominal pressure appears to be a contributing factor

Learning curve takes 65 repetitions of totally extraperitoneal laparoscopy on inguinal hernias for reduction of operating time and complications

Abstract: Inguinal hernia repair is one of the most frequently conducted surgical procedures worldwide. Totally extraperitoneal (TEP) hernioplasty has shown many advantages over traditional open surgery. However, because of increased surgical complexity, it requires more practice to achieve optimal results. The aim of this study is to evaluate the learning curve for TEP hernioplasty, analysing parameters related to the mean operating time. The secondary objective is to assess the complications and early discharge rates related to this procedure. A prospective study of 238 consecutive patients undergoing TEP hernioplasty from the same practitioner between May 2009 and May 2014, in a specialised centre for abdominal hernias in Sao Paulo, Brazil, was conducted. All data were obtained through medical records. The study included 137 patients undergoing a total of 157 TEP hernia repairs. Bilaterality and complications can influence the operating time and so were excluded. Patients with unilateral surgery and without complications were included. Patients were chronologically divided into four groups. Groups 1–3 were composed of 35 patients and group 4 of 32. There were no significant variations in clinical characteristics between the groups. The plateau of the learning curve was reached on the 65 th repetition of the surgery, with a mean operating time of 28 min (p < 0,05). Complications were only observed in the first group of 35 patients. 97% of patients were discharged early, defined as patient leaving hospital less than 12 h after surgery. After an initial reduction, the mean operating time stabilised after 65 cases. A reduction in the rate of complications was observed after 35 cases, and a rate of 97% of early discharge was achieved.