Smartphones are advanced devices that have evolved beyond basic calling and messaging functions, offering features comparable to computers due to the development of mobile operating systems. In addition to their technical capabilities, smartphones have become increasingly appealing to children, adolescents, and adults through continuously updated websites, applications, and social networks that provide access to current information and opportunities for social interaction.

Excessive use of smartphones and similar technological devices can be defined as mobile phone addiction or internet addiction. The risk of smartphone addiction is particularly high among children and adolescents. The prolonged use of smartphones, which are now an integral part of daily life, may negatively affect physical capacity, including the musculoskeletal system. Previous studies have shown that increased smartphone use is associated with neck/shoulder and upper extremity/back discomfort. This increased usage can lead to non-neutral spinal postures and sustained muscular loading. Due to the central role of the spine within the kinetic chain, postural changes and muscular strain in the spine may affect movement quality in both upper and lower segments. For example, excessive neck flexion while texting can have widespread effects on spinal alignment and function. Therefore, smartphone use may cause significant changes in thoracic kyphosis and lumbar lordosis.

Thoracic hyperkyphosis is commonly detected during adolescence and encompasses a range of spinal deformities from mild postural changes to rigid deformities accompanied by soft tissue and structural alterations. In children and adolescents, three main types of hyperkyphosis are observed: postural kyphosis, Scheuermann's kyphosis, and congenital kyphosis.

Postural hyperkyphosis is the most common type. It results from the weakness of antigravity muscles responsible for upright posture, leading to curvature of the spine under external forces. This type of curvature is not rigid and can often be corrected voluntarily when the individual is instructed to stand upright. Postural hyperkyphosis typically occurs during adolescence and is characterized by a thoracic kyphosis angle generally below 65 degrees. It is a common yet often overlooked condition in healthy adolescents and can be identified through school screenings.

Today, the growing use of smartphones and the associated rise in technology addiction have contributed to the increasing prevalence of postural hyperkyphosis, which is caused by prolonged incorrect postures. It has also been reported that postural habits developed during childhood often persist into adulthood.

If left untreated, hyperkyphosis that begins in adolescence may continue into adulthood, potentially increasing healthcare expenditures. With the rising incidence of hyperkyphosis linked to smartphone addiction, it is crucial to address this deformity beginning in adolescence, both from a health and economic perspective. Many authorities advocate for the inclusion of scoliosis and hyperkyphosis in school screening programs. However, routine screenings for skeletal system problems are not conducted in schools. Moreover, the limited number of studies in this area have primarily focused on scoliosis, and to date, no screening studies have addressed hyperkyphosis specifically.

Inclusion Criteria:

• Being between 7-14 years old
• Using a smartphone for more than a year
• Daily smartphone usage time >60 minutes

Exclusion Criteria:

• Those who have had major surgery or trauma related to the musculoskeletal system, especially the spine and upper extremities
• Difficulty in perceiving commands
• Rigid deformity in the spine (Scheuermann Kyphosis)
• Congenital deformity

Individuals between the ages of 7 and 14 who are receiving primary education and meet the inclusion criteria will be included in this study planned to evaluate the relationship between smartphone addiction and thoracic hyperkyphosis in children with thoracic hyperkyphosis.