Prenatal Hormonal Markers and Sleep Characteristics in Young Adults With Joint Hypermobility

NCT07157930 | Completed

• 1 other identifier: Joint Hypermobility and 2D:4D
• Study Type: observational
• Target: 180
• Locations: 1 country
• Sites: 1

Brief Summary

Joint hypermobility is a clinical condition characterized by joints having a range of motion beyond their normal limits. Hormonal factors are thought to play a role in the development of joint hypermobility. One of the most significant indicators of prenatal androgen exposure is considered the ratio of the lengths of the second and fourth fingers (2D:4D). The 2D:4D digit ratio refers to the ratio of the lengths of the second finger (2D; index digit ) and the fourth finger (4D; ring digit). Evidence suggests that the 2D:4D ratio is developmentally stable and stabilizes from the second trimester of pregnancy onward. To our knowledge, intrauterine androgen exposure (2D:4D) has not been examined in populations with joint hypermobility. Therefore, the planned study aimed to examine the 2D:4D digit ratio in young adults with joint hypermobility and compare it with that of individuals without joint hypermobility.

Conditions

Joint Hypermobility; Healty Controls; Sleep; Androgen Effect; Hormonal

Keywords

joint hypermobility; sleep; 2D:4D; digit ratios

Outcome Measures

Primary Outcomes (2)

• Beighton Scoring System

  Individuals will be assessed for joint hypermobility (Beighton Scoring System) by a physical therapist. The Beighton Scoring System is widely used to distinguish individuals with generalized joint hypermobility from those without. The Beighton Scoring System consists of: * Passive dorsiflexion of the fifth metacarpophalangeal joint * Passive hyperextension of the elbow * Passive hyperextension of the knee joint * Passive placement of the thumb on the flexor side of the forearm * Forward flexion of the trunk In adults up to 50 years of age, a score of ≥5 out of 9 indicates joint hypermobility, while in adults over 50, a score of ≥4 out of 9 is considered positive for joint hypermobility.

  1 month

• 2D:4D Digit Ratio

  The lengths of the second (2D) and fourth (4D) digits will be measured separately on both hands. Measurements will be taken with the participants' hands placed on a flat surface with the palms facing upward. Digit length will be defined as the distance from the midpoint of the proximal crease at the base of the finger to the distal tip of the finger. A digital caliper with a precision of 0.01 mm will be used, and two separate measurements will be obtained for each finger, with the mean value recorded. Based on these measurements, the 2D:4D digit ratio will be calculated for each hand by dividing the length of the second digit by that of the fourth digit. To enhance reliability, assessments will be performed independently by two different researchers, and inter-rater agreement will be evaluated.

  1 month

Study Arms (2)

Young Adults With Joint Hypermobility

Joint hypermobility makes individuals more vulnerable to trauma through increased joint range of motion, changes in neuromuscular reflexes, and decreased joint position sense. The Beighton Scoring system is widely used to distinguish individuals with generalized joint hypermobility from those without.In adults up to 50 years of age, a score of ≥5 out of 9 indicates hypermobility, while in adults over 50, a score of ≥4 out of 9 is considered positive for hypermobility. The study will include young adults aged 18-35 with joint hypermobility. It has been reported in the literature that estrogen may be associated with connective tissue laxity and joint hypermobility. The 2D:4D digit ratio will be assessed and compared with young adults without joint hypermobility.

Behavioral: The Beighton Scoring system; Behavioral: 2D:4D Digit Ratio

Healthy Controls (without joint hypermobility)

This group consisted of individuals without generalized joint hypermobility, confirmed by a Beighton score below the diagnostic cut-off. This study will include young adults aged 18-35 who do not have joint hypermobility.The Beighton Scoring system is widely used to distinguish individuals with generalized joint hypermobility from those without.In adults up to 50 years of age, a score of ≥5 out of 9 indicates hypermobility, while in adults over 50, a score of ≥4 out of 9 is considered positive for hypermobility. Individuals with musculoskeletal, neurological, or systemic conditions that may affect joint mobility will be excluded from the study.

Behavioral: The Beighton Scoring system; Behavioral: 2D:4D Digit Ratio

Interventions

2D:4D Digit Ratio BEHAVIORAL

The lengths of the second (2D) and fourth (4D) digits will be measured separately on both hands. Measurements will be taken with the participants' hands placed on a flat surface with the palms facing upward. Digit length will be defined as the distance from the midpoint of the proximal crease at the base of the finger to the distal tip of the finger. A digital caliper with a precision of 0.01 mm will be used, and two separate measurements will be obtained for each finger, with the mean value recorded. Based on these measurements, the 2D:4D digit ratio will be calculated for each hand by dividing the length of the second digit by that of the fourth digit. To enhance reliability, assessments will be performed independently by two different researchers, and inter-rater agreement will be evaluated.

Healthy Controls (without joint hypermobility); Young Adults With Joint Hypermobility

The Beighton Scoring system BEHAVIORAL

The Beighton Scoring System is widely used to distinguish individuals with generalized joint hypermobility from those without. The Beighton Scoring System consists of: • Passive dorsiflexion of the fifth metacarpophalangeal joint • Passive hyperextension of the elbow • Passive hyperextension of the knee joint • Passive placement of the thumb on the flexor side of the forearm • Forward flexion of the trunk In adults up to 50 years of age, a score of ≥5 out of 9 indicates joint hypermobility, while in adults over 50, a score of ≥4 out of 9 is considered positive for joint hypermobility.

Healthy Controls (without joint hypermobility); Young Adults With Joint Hypermobility

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)
• Sampling Method: Non-Probability Sample

Study Population

The study planned to include individuals with (Beighton skorlamasına göre 9 üzerinden 5 ve daha fazla puan alan) and without joint hypermobility. Individuals between the ages of 18 and 35 will be included.

You may qualify if:

• Individuals aged 18-35
• Individuals who scored 5 out of 9 or higher on the Beighton score
• Control group: Those with a Beighton score of ≤ 4

You may not qualify if:

• Individuals with any pathology related to the musculoskeletal system
• Individuals diagnosed with metabolic, neurological, or genetic diseases (tissue diseases such as Ehlers-Danlos syndrome and Marfan syndrome)
• Those with a history of surgery within the last 6 months
• Those who are pregnant or breastfeeding

Sponsors & Collaborators

• Nigde Omer Halisdemir University: lead

Study Sites (1)

Nigde Omer Halisdemir University

Niğde, Turkey (Türkiye)

Location

Related Publications (5)

• Fink B, Manning JT, Neave N. The 2nd-4th digit ratio (2D:4D) and neck circumference: implications for risk factors in coronary heart disease. Int J Obes (Lond). 2006 Apr;30(4):711-4. doi: 10.1038/sj.ijo.0803154.

  PMID: 16261185 BACKGROUND

• Engelbert RH, Bank RA, Sakkers RJ, Helders PJ, Beemer FA, Uiterwaal CS. Pediatric generalized joint hypermobility with and without musculoskeletal complaints: a localized or systemic disorder? Pediatrics. 2003 Mar;111(3):e248-54. doi: 10.1542/peds.111.3.e248.

  PMID: 12612280 RESULT

• Smits-Engelsman B, Klerks M, Kirby A. Beighton score: a valid measure for generalized hypermobility in children. J Pediatr. 2011 Jan;158(1):119-23, 123.e1-4. doi: 10.1016/j.jpeds.2010.07.021. Epub 2010 Sep 17.

  PMID: 20850761 RESULT

• Yildiz R, Yildiz A, Zorlular R, Elbasan B. Relationship between sensory processing skills and motor skills in 12-month-old infants. Brain Behav. 2024 Sep;14(9):e70052. doi: 10.1002/brb3.70052.

  PMID: 39317996 RESULT

• Zorlular R, Zorlular A. Prenatal Hormonal Markers in Individuals With Joint Hypermobility: The Role of the 2D:4D Digit Ratio. Am J Hum Biol. 2026 Feb;38(2):e70217. doi: 10.1002/ajhb.70217.

  PMID: 41693451 DERIVED

MeSH Terms

Conditions

Joint Instability

Condition Hierarchy (Ancestors)

Joint Diseases; Musculoskeletal Diseases

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: principal investigator

Study Record Dates

• First Submitted: August 28, 2025
• First Posted: September 5, 2025
• Study Start: August 20, 2025
• Primary Completion: December 17, 2025
• Study Completion: December 17, 2025
• Last Updated: December 24, 2025

Record last verified: 2025-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)