## 13 Discussion
In our cohort of 301 patients treated with the Hummer method, the most common complications were minor wound-healing problems, pneumothorax (5 requiring therapy), pleural effusion (6 aspirated, 9 drained), transient paresthesia, and hypertrophic or widened scars. Implant dislocation occurred in 5 patients (1.7%). The Nuss MIRPE procedure is also frequently associated with complications such as pneumothorax, infection, and metal migration. There are some reported cases of cardiac perforation and other organ injury [39, 40, 42], although the overall incidence of life-threatening complications of minimally invasive pectus surgery is estimated to be less than 0.1% [43]. Many modifications have been described focusing on reducing the risk of complications, improving the aesthetics, pain control [44], or adapting to new circumstances, such as use in adults whose chest is not as flexible [45]. The study by [PERSON] et al. in 2001 found a displacement of the metalwork in 11% of cases and a re-operation in 29% of cases, with other causes including infection, hemothorax, pain, and the development of secondary pectus carinatum. Long-term complications occurred in 17% of the patients, such as pain requiring early implant removal, pectus carinatum, or significant chest wall asymmetry [40]. Major complications were reported in 11.1% and minor complications in 8.1% of patients [46]. In a study by [PERSON] et al., the Nuss procedure was associated with an increased incidence of hemothorax, pneumothorax, and the need for reintervention when compared to the Ravitch procedure. They found no statistically relevant differences in overall complications, blood transfusion, hospital stay, and time to ambulation. The Nuss procedure was faster than the Ravitch procedure in this study (mean difference = \(-\)69.94 min) [47]. [PERSON] et al. [48] reported complications such as pneumothorax and subcutaneous emphysema in 30%, late complications such as bar displacement in 10%, and deformity recurrence in 6.6%. Recent publications [49] indicate that the complication rate has decreased in recent years (displacement of the implanted steel bar in 4.5%, infection of the surgical site in 2.9%, pneumothorax in 2.7% patients, pleural effusion in 2.5%, and chronic pain in 2.2%). The complication rate appears to be higher in adults [49]. Routine removal of the metalwork is performed after 12 months in the Hummer method and after 2 years-4 years in the MIRPE method. At the time of removal, 21.9% of our patients underwent scar correction and 7.6% underwent the smoothing out of small step deformities in the ribs. It has been shown that the majority of concomitant deformities of the costal arch deformities correct themselves spontaneously after elevation of the pectus excavatum, so we prefer to wait and perform a second procedure only if necessary. In our study, this was only necessary in 9% of the patients and they underwent unilateral or bilateral costal arch surgery via stab incisions at the same time as implant removal. The recurrence rate requiring reoperation is reported in the literature to be 1.3% for the Hummer procedure [13] and 7.8% for the MIRPE procedure [50]. In addition to physiological problems, psychosocial difficulties are prominent in patients with pectus excavatum. Affected patients report significantly lower scores for quality of life, body image, and self-esteem compared to age-matched controls [2]. This can lead to social withdrawal, relationship anxiety, and reactive psychological disorders [2, 3, 13]. Analysis of patient satisfaction questionnaires after the Hummer repair method shows that 75% of patients are satisfied or very satisfied, and 76% would be willing to undergo the procedure again. Postoperatively, the patients rated their quality of life higher than age-matched healthy controls. This is consistent with other studies indicating that correction of chest wall deformity in general can significantly improve patients' body image and self-esteem [51].