Introduction: Aberrant Mongolian spots are postulated to appear at birth, or shortly thereafter, and gradually fade by the age of two. However, few studies have quantitatively evaluated this change. In this study, we used a spectrophotometer to quantitate the color of aberrant Mongolian spots and evaluated temporal changes.
 Methods: We examined 26 lesions in 15 children under two years of age with aberrant Mongolian spots. We measured the color of the lesions and the surrounding normal skin using a spectrophotometer. Color differences and temporal changes were calculated.
 Results: Each site was measured two to five times and a total of 68 measurements were performed. Analysis of temporal changes in color difference revealed that 30 children (71.4%) showed no change, 10 (23.8%) showed a decrease, and two (4.8%) showed an increase.
 Conclusion: Traditionally, Mongolian spots have been postulated to become prominent by approximately two years of age and then gradually fade. However, our findings suggest that in many children, the color difference decreases before the age of two. Our findings suggest that fading may begin earlier than previously postulated.

 A 31-year-old female presented with a congenital skin protrusion in the sacrococcygeal region. She exhibited no neurological symptoms, and preoperative imaging confirmed no connection of the protrusion with the spinal cord. Surgical excision of the protruding skin and coccyx was performed, without postoperative complications. Histopathological examination revealed normal skin and subcutaneous tissue without secondary changes such as hyperkeratosis or epidermal thickening due to chronic irritation. Preoperative imaging is crucial for evaluating the presence of tethered cord syndrome, which can lead to lower-limb paralysis and bladder or rectal dysfunction. The absence of histopathological changes related to chronic irritation is a characteristic feature of the congenital human tail. In the present case, histopathological analysis was essential for confirming the diagnosis.

 Glomus tumors are common in the fingertips and subungual regions but are relatively rare in the perioral region. We report a case of a 14-year-old male with a glomus tumor in the left side of the lower lip. Magnetic resonance imaging and computed tomography initially suggested a venous malformation, prompting surgical excision; however, histopathological examination confirmed the diagnosis of a glomus tumor. The tumor recurred one year and five months after the initial surgery and was re-excised three years postoperatively. Thirteen months after the second surgery, there has been no local recurrence. Herein, we review and summarize domestic and international reports of glomus tumors published over the past 40 years.

 Currently, autologous tissues, such as free cartilage fragments and artificial materials, are widely used as support materials for rigid reconstruction of the trachea. There have been few reports of the use of a sternocleidomastoid muscle-clavicle myoosseous flap.
 The patient was a 53-year-old woman with papillary thyroid carcinoma (cT4aN0M0) invading the trachea. In addition to total thyroidectomy, two-thirds of the tracheal circumference, from the inferior border of the cricoid cartilage to the fourth tracheal ring, were resected. Tracheal reconstruction was performed using a sternocleidomastoid muscle-clavicle myoosseous flap with partial clavicular division. The tracheal lumen was maintained postoperatively.
 In 1972, Conley reported the use of sternocleidomastoid muscle-clavicle myoosseous flap as a composite flap, which included the sternocleidomastoid muscle and clavicle. We modified this technique and applied it for tracheal reconstruction following thyroid cancer resection. Here, we report successful maintenance of the tracheal lumen with a review of the related literature.

 Cranial reconstruction is important to protect the brain; prevent complications, such as infection and sinking skin flap syndrome; and restore cranial contour.
 We present a case of a 72-year-old man who developed a skull deformity following removal of a resin graft previously used for cranioplasty after meningioma resection. To treat the defect, we used a custom-made hydroxyapatite implant and a single free latissimus dorsi musculocutaneous flap. The flap was folded to fill the epidural dead space and cover the artificial bone. Stable blood flow was ensured using the facial artery and vein.
 This technique enabled simultaneous dead space filling and graft coverage using a single flap, without the need for a complex flap design. This technique may be a useful option for patients at high risk of infection or ulceration. Careful postoperative neurological monitoring is essential for preventing complications such as cerebral edema.