Introduction: Despite the fact that the pilonidal cyst of the sacrococcygeal region is a long-known disease, the mechanism of accumulation or absence of hair in the cyst remains unclear, which affects the accuracy of the name of the disease, as well as understanding of its pathogenesis. Aim: Aim to perform morphological examination of pilonidal cysts of the sacrococcygeal region, to determine the nature of the cysts, the frequency of hair in the cyst cavity and to determine the causes and mechanism of its accumulation in cysts. Materials and methods: A morphological study of skin areas with altered tissues of the sacrococcygeal region after radical surgical treatment of 235 patients with a coccygeal cyst of the sacrococcygeal region was carried out. The gender distribution of patients with pilonidal cysts was as follows: 220 (93.4%) male patients, 15 female patients (6.6%). Results: Among 235 patients who underwent radical surgical treatment, the absence of hair shafts was recorded in 112 (46.8%) cases, hair in the cyst structure – in 123 male patients (53.2%), both visually and under a microscope, and in 4 of them (0.9%) only under a microscope. Among 15 patients, hair in the cyst cavity was found in 1 case (0.4%), in 14 patients they were not detected either visually or by microscopic examination. Discussion: Having observed the formation of foreign body granuloma and the accumulation of polynuclear histiocytes of foreign bodies around the hair in the pilonidal cyst cavity, a proportional increase in histiocytes depending on the number of hairs, that is, the body's reaction to the foreign body was registered. However, multinucleated histiocytes in lower numbers were also observed in cases in which hair shafts were not found either microscopically or macroscopically, which may indicate both completed phagocytosis and formation of a cyst without a hair component, registering the reaction of histiocytes to inflammatory changes in the cyst cavity. The detection of atypically located pilonidal cysts (cheek, navel) provides additional confirmation of the formation of pilonidal cyst as a result of disturbance of hair growth through the hair funnel due to inflammatory changes in the hair follicle and their accumulation subcutaneously.

Pilonidal cyst of the sacrococcygeal region is an acquired disease with the prevalence of up to 5% in the population. The overwhelming majority of patients, up to 75-80%, are males. A great number of more or less invasive methods of surgical treatment of this disease have been developed, but the results of treatment are often not satisfactory. A significant frequency of relapses of the disease, delayed healing of postoperative wounds are common. Considering the etiology and pathogenesis of this disease, a connection is visible between other pathologies: acne inversa, Hoffman's folliculitis, acne conglobata. These diseases are united by the syndrome of follicular occlusion, a condition when a lack of cytokeratin C17 leads to fragility of the sebaceous gland duct wall and inflammation of the skin tissues surrounding the hair follicle and sebaceous gland. Dermatologists successfully use retinoids, for example isotretinoin, which effectively affect the sebaceous glands, normalizing their activity and size. An integrated approach to the treatment of pilonidal cysts, an effective combination of surgical methods with a drug effect on the sebaceous glands of the skin will more efficiently solve the problem of treatment efficacy, and reduce the recurrence rate.

The aim. Improve results of the surgical treatment of recurrent inguinal hernias after Lichtenstein's surgery by using an advanced TAPP technique. Materials and methods. An analysis of the surgical treatment of patients with recurrent inguinal hernias after Lichtenstein's surgery using traditional and improved preperitoneal transabdominal alloplasty (TAPP), for the period of 2012–2019, was performed. The traditional TAPP technique was performed for 52 patients who made up the 1st group. An improved TAPP technique was implemented for 53 patients who composed the 2nd group. The features of the improved TAPP technique, which was different from the traditional one, were by additional mobilization of the parietal peritoneum by 3–4 cm along the upper edge of the defect, the mesh implant was used with a larger size in comparison to the classical one – 15×15 cm and fixed, besides the traditional points, additionally on the lower and lateral edges with medical glue Sulfacrylate. Results. The results of surgical treatment in the early postoperative period were not significantly different and were comparable. During the long-term period, 51 patients from the 1st group, and 50 patients from the 2nd group were examined. Thus, in the first group in 4 (7.9 %) cases during 6 months period after the application of the traditional TAРР technique, chronic pain was observed on the site of the implanted mesh; among the 2nd group of patients chronic inguinal pain was not observed. In 5 (9.8 %) patients of the 1st group, the recurrence of inguinal hernia was diagnosed, instead of the 2nd group, where relapse was observed in 1 (2 %) case. Conclusions. Thereby, the results of the traditional and improved TAPP techniques confirm the higher efficiency of the improved technique, due to the absence of the chronic inguinal pain and a lower rate of relapses, which is achieved by wider mobilization of the parietal peritoneum along the upper edge of the defect, and usage of the larger mesh and its additional fixation by gluing it at the lower lateral edge.

Introduction. The frequency of the inguinal hernia of the repeated recurrences is up from 9,3 to 12%. In surgical treatment re-fixation of the mesh to the atrophied tissues of the inguinal canal is unreliable. The posterior access can be much more reliable for the patients, in which the mesh will be fixed to the unchanged muscular-aponeurotic tissues of the inguinal area. Aim. To increase the efficiency of recurrent inguinal hernias surgical treatment by justification of using the TAPP surgical technology.