This study was conducted as a clinical trial in Hospitals related to Isfahan University of Medical Sciences. Children over the age of 7 years old suffering from concealed penis were included in this study. The children with any coagulation disorder and children whose parents didn’t consent were excluded from this study, and eventually, the study population was 25 patients with this condition. All the participants were suffering from congenital concealed penis without a history of previous surgery. The sample size was calculated using the following equation:

$$\:n=\:\frac_+_})}^\times\:^}^}$$

In this study, the confidence interval and the power were considered 95% and 80% respectively. The hypothesized difference and population variance were considered 0.5 regarding the similar studies on this matter [10].

After examining the patient at the first visit and after diagnosing the disorder, a detailed history of being term or preterm at the time of delivery, the mother’s illnesses during pregnancy, possible disorders in other children of the family, type of delivery, and history of hospitalization was taken from parents. Then, pre-operative paraclinical evaluations, including coagulation tests and blood cell count, were evaluated.

After admitting the patient to perform the operation, they were placed under general anesthesia and put in the low lithotomy position. After prep and drape, the genital area and lower limbs were placed in the field. A median longitudinal incision was made on the ventral penile skin from the phimotic ring to the penoscrotal junction. For traction with Prolene 5.0, a permanent suture was placed at a distance of 5 mm from the edge of the glans and remained until the end of the operation. A circumferential incision was created near the initial opening. Degloving was performed by dissection of the entire dartos penile fascia and the fibrous tissues of the buck’s fascia [11]. The penile shaft remained untouched.

Then, after tying the tourniquet at the base of the penis and injecting normal saline, the amount of Chordia was checked. If the severity of the chordia was more than 10 degrees, it was corrected by Dorsal Plication with 0–5 Prolen thread using the Nesbit method. The subcutaneous tissue of the junction of the penoscrotal was dissected ventrally at the 6 o’clock position. This simplified dissection of the genital adipose tissue from the back to the location of the pubic ligaments at 12 o’clock.

Then, a full-thickness graft with a length of 1.5 times the defect and a width of 1 cm was taken from the non-dominant thigh and defatted. This region was chosen because it is hairless and next to the penis, and the resulting scar is easily hidden under clothing. Then, the graft was transferred to the operation site and fixed at 12, 3, and 9 o’clock, and at 6 o’clock, the genital area of the graft was repaired in the form of a ring.

A urethral catheter was used based on the patient’s age, and Antibiotics were prescribed during the induction of anesthesia and are maintained for 3 to 5 days. The operation was finished by applying a usual dressing for the graft, including layers of Vaseline and wet gauze on the penis. After 48 h, the dressing was removed, and the graft’s color and condition were checked.

The patients were visited as an outpatient a week after the operation and were examined for possible complications of the operation (infection, hematoma, seroma). Then, the investigation and the studied variables were examined and recorded in one-month, three-month, six-month, and one-year follow-up periods after the operation on an outpatient basis in the clinic. The deformation of the penis was recorded by measuring its roots with finger pressure on both sides of the penis before surgery and in subsequent visits.

Relevant training was given to the parents to check the improvement of the health status and function of the penis during discharge, which was in the form of evaluation of the reduction of sub-genital debris after surgery (in the improvement of the hygiene status) and assessment of the progress of the child’s urinary erection during voiding (in the improvement of the function of the penis). These items were recorded in the checklist during the postoperative visits, after examination, and after asking parents.

Also, a complete examination for unwanted complications such as infection, hematoma, and seroma of the operation site on the first visit or contracture in consecutive visits up to one year is performed and recorded if they occur.

Finally, the data is extracted and analyzed from within the checklist. The analysis will be done in two descriptive and analytical parts. Before-and-after comparisons in the studied subjects will be done using a paired t-test based on quantitative variables or McNemar’s test based on qualitative variables. All analyses will be done using SPSS software version 24 and at an error level of 5%.