Sagittal Spinopelvic and Coccygeal Alignment in Sitting and Standing Positions in Coccydynia

NCT ID: NCT07076927

Last Updated: 2025-07-22

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 50 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2024-08-01
• Study Completion Date: 2025-05-25

Brief Summary

This observational cross-sectional study aims to investigate the differences in spinopelvic and coccygeal morphometric parameters in standing and sitting positions among patients diagnosed with coccydynia. A total of 50 adult patients (aged 25-65 years) diagnosed with coccydynia based on clinical evaluation and imaging findings were included. Lateral radiographs were obtained in both standing and sitting positions. Radiological assessments included spinopelvic parameters such as sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), sacral table angle (STA), and sacral kyphosis (SK), along with coccygeal morphology based on the Postacchini-Massobrio classification. The study further aimed to explore whether these morphometric differences are associated with the presence of low back pain and to assess variations across different coccygeal morphology types.

Detailed Description

Coccydynia is a condition characterized by pain in the coccygeal region, often exacerbated by sitting and postural changes. While its etiology is multifactorial, anatomical variations in coccygeal and spinopelvic alignment may play a significant role in symptom development. Despite increasing attention to coccygeal mobility and morphology in radiological evaluations, the relationship between coccygeal type, spinopelvic alignment, and posture-specific morphometric changes has not been fully clarified.

This observational cross-sectional study was designed to evaluate morphometric parameters of the sacropelvic and coccygeal regions in both standing and sitting positions in patients diagnosed with coccydynia. The study included 50 adult patients (42 female, 8 male) aged between 25 and 65 years who were diagnosed with coccydynia based on clinical findings and radiological confirmation. Lateral radiographs were obtained in both weight-bearing and seated positions to allow for comparative measurement.

The following radiological parameters were assessed: thoracic kyphosis (TK), lumbar lordosis (LL), sagittal vertical axis (SVA), thoracopelvic angle and its modification (TPA-T1PA), sacral slope (SE), pelvic incidence (PI), pelvic tilt (PT), spinosacral angle (SSA), sacral table angle (STA), and sacral kyphosis (SK). Coccygeal features were evaluated based on vertebral segment number, sacrococcygeal and intercoccygeal joint fusion, segmental angulation, and mobility status. Morphological types were categorized using the modified Postacchini-Massobrio classification. The presence of coccygeal spicules and their frequency across types were recorded. Dynamic morphometric assessments included sacrococcygeal angle (SKA), intercoccygeal angle (IKA), coccygeal height (KY), sacral height (SY), and sacrococcygeal height (SKY). Mobility was determined by comparing the angular displacement between standing and sitting radiographs and classified as normal, hypermobile, hypomobile, or posterior luxation, depending on the flexion-extension response and translation under load.The study aimed to investigate the changes in these parameters between postures and explore whether these variations are associated with the presence of low back pain and functional impairment. Additionally, differences among coccygeal morphology subgroups in terms of spinopelvic parameters were analyzed.

Conditions

Coccydynia; Sagittal Balance; Morphological Analysis and Classification

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: CROSS_SECTIONAL

Study Groups

Coccydynia

Coccydynia patients

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

Patients aged between 25 and 65 years

Clinically diagnosed with coccydynia

Provided informed consent to participate in the study

Exclusion Criteria

Presence of any disease that may cause spinal malalignment

Any hip- or knee-related condition that may lead to spinal malalignment

History of surgery involving the cervical, thoracic, lumbar, or coccygeal spine

• Minimum Eligible Age: 25 Years
• Maximum Eligible Age: 65 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Fatih Sultan Mehmet Training and Research Hospital

OTHER

Sponsor Role: lead

Responsible Party

Aslinur Keles Ercisli, MD, PhD

Principal Investigator

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Aslinur Keles, MD., PhD

Role: PRINCIPAL_INVESTIGATOR

Fatih Sultan Mehmet Training and Research Hospital

Locations

Fatih Sultan Mehmet Training and Research Hospital

Istanbul, , Turkey (Türkiye)

Fatih Sultan Mehmet Training and Research Hospital

Istanbul, , Turkey (Türkiye)

Countries

Turkey (Türkiye)

Other Identifiers

2024/4-4/6

Identifier Type: -

Identifier Source: org_study_id