Smartphone Addiction on the Biomechanical Properties of Thumb Muscles and Thumb Sensory Sensitivity

Recruiting

• Conditions: Smartphone Addiction; Thumb Injury

• Registration Number: NCT07040267
• Lead Sponsor: Saglik Bilimleri Universitesi

Brief Summary

This study will aim to assess the effects of smartphone addiction on thumb muscle biomechanics and sensory sensitivity among university students. The research will investigate whether excessive smartphone use leads to significant differences in muscle tone, stiffness, elasticity, and sensory discrimination capabilities.

Detailed Description

This will be a prospective, non-randomized, controlled observational study designed to examine the impact of smartphone addiction on the neuromuscular and sensory function of the thumbs. A total of 36 university students aged 18 to 30 will be recruited and categorized into two groups based on their scores from the Smartphone Addiction Scale - Short Version (SAS-SV): addicted and non-addicted.

Participants' weekly screen times will be recorded, and the smartphone applications used will be categorized. The MyotonPro™ device will be used to measure the biomechanical properties of three thumb muscles (abductor pollicis brevis, flexor pollicis brevis, and opponens pollicis) in both hands. Sensory function will be assessed bilaterally using the Baseline Aesthesiometer via two-point discrimination testing.

This study will evaluate whether significant biomechanical or sensory changes are observable among addicted users compared to non-addicted users, and whether screen time is correlated with any muscular or sensory outcomes.

Study Timeline

• Study First Submitted: 2025-06-18
• Study First Submitted QC: 2025-06-26
• Study First Posted: 2025-06-27
• Status Verified: 2025-07
• Study Start: 2025-07-01
• Last Update Submitted: 2025-07-01
• Last Update Posted: 2025-07-02
• Primary Completion: 2026-07-01
• Study Completion: 2026-07-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 36

Inclusion Criteria

• Aged 18-30 years
• Currently enrolled university students
• Regular smartphone users

Exclusion Criteria

• Presence of systemic, chronic, or neuromuscular disorders
• History of upper limb surgery or trauma
• Neurological or orthopedic conditions affecting upper extremities
• Subcutaneous fat over target muscles >20 mm
• Presence of wounds or burns on the measurement area

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
MyotonPro™ Muscle Assessment	Baseline	This device will be used to assess muscle tone, stiffness, and elasticity in the abductor pollicis brevis, opponens pollicis, and flexor pollicis brevis muscles of both hands. Measurements will be performed with the participant in a standardized seated position.

Secondary Outcome Measures

Name	Time	Method
Baseline Aesthesiometer Sensory Assessment	Baseline	This instrument will be used to evaluate thumb sensory sensitivity through two-point discrimination testing on both hands. Participants will be blindfolded during the procedure and tested at the distal phalanx of the thumb.
Smartphone Addiction Scale - Short Version (SAS-SV)	Baseline	The Smartphone Addiction Scale - Short Version (SAS-SV) is a validated self-report questionnaire developed to assess the risk of smartphone addiction, particularly in adolescents and young adults. It consists of 10 items, each rated on a 6-point Likert scale ranging from 1 (strongly disagree) to 6 (strongly agree). The total score ranges from 10 to 60, with higher scores indicating a greater risk of smartphone addiction.

Trial Locations

Locations (1)

Esra Pehlivan; 🇹🇷 İstanbul, Üsküdar, Turkey