Proprioceptive, Fear-related and Inflammatory Factors in the Persistence of Pregnancy-related Lumbopelvic Pain.

Not Applicable

Recruiting

• Conditions: Low Back Pain; Lumbopelvic Pain; Pelvic Girdle Pain

• Registration Number: NCT06785909
• Lead Sponsor: Hasselt University

Brief Summary

Pregnancy-related lumbopelvic pain (PLPP) affects 50-90% of pregnant women and is often dismissed as a normal part of pregnancy. However, the long-term consequences can be dramatic. Up to 21% of women with PLPP still have pain three years postpartum, and 10% experience disability, poorer quality of life, and lower ability to work 11 years after delivery. Because the multifactorial etiology of PLPP is unclear, prevention and treatment fall short. Previous studies on the causes of PLPP focused on impairments in motor output but ignored that impairments in sensory input (e.g., proprioception, the primary expertise of our research group) often precede motor output problems. Moreover, though psychological factors such as fear (of movement) are known to affect PLPP, their predictive role in PLPP remains understudied. Finally, the role of systemic inflammation in PLPP has yet to be examined, despite recent studies demonstrating its role in the chronification of lumbopelvic pain in the general population.

This prospective cohort study aims to identify new modifiable predictors for the onset of PLPP during pregnancy and its persistence postpartum. The investigators will compare sensory (proprioception, body perception), fear-related, and inflammatory factors between women with and without PLPP and determine their predictive role in the onset and persistence of PLPP. The results will increase our understanding of the multifactorial etiology of PLPP and help optimize prevention and treatment.

Detailed Description

This study comprises a prospective cohort study with three objectives.

Objective 1 is to investigate whether the reliance on lumbar versus ankle proprioception during standing and body perception at the lower back (i.e., "proprioceptive factors"), anxiety, fear of movement, pain catastrophizing, depression, stress, and coping with stressful situations (i.e. "fear-related factors"), and inflammatory markers (i.e., "inflammatory factors") change over time and differ between women with and without PLPP in the 3rd pregnancy trimester, 6 weeks postpartum, and 9 months postpartum. We hypothesize that women with PLPP show (1a) a maladaptive reliance on ankle proprioception and/or disturbed body perception at the lower back, (1b) higher levels of fear of movement, anxiety, stress, depression, pain catastrophizing and poorer coping with stress, and (1c) greater immune activation and a disturbed balance of pro- vs. anti-inflammatory markers compared to pain-free women.

Objective 2 is to determine whether the proprioceptive, fear-related, and inflammatory factors are correlated in women with PLPP. Based on previous findings (52-55), we hypothesize that anxiety correlates with higher concentrations of IL-6 and IL-12, and lower concentrations of IL-2 and IL-10. We will also examine whether maladaptive reliance on ankle proprioception and disturbed body perception at the lower back correlate with fear of movement, anxiety, and concentrations of inflammatory markers in women with PLPP.

Objective 3 (= primary objective) is to investigate whether the proprioceptive, fear-related, and inflammatory factors predict the presence of PLPP in the 3rd trimester, 6 weeks postpartum and 9 months postpartum. Based on (our own) research (20,26,33,38,39,56), we hypothesize that a maladaptive reliance on ankle proprioception and disturbed body perception at the lower back, higher levels of anxiety and fear of movement, and immune activation and disturbed balance of pro- and anti-inflammatory markers in the 1st trimester predict having PLPP in the 3rd trimester. We also expect that the presence of these factors in the 3rd trimester predicts the persistence of PLPP 6 weeks and 9 months postpartum.

Study Timeline

• Study First Submitted: 2025-01-13
• Study First Submitted QC: 2025-01-20
• Study First Posted: 2025-01-21
• Status Verified: 2025-03
• Study Start: 2025-03-03
• Last Update Submitted: 2025-03-11
• Last Update Posted: 2025-03-13
• Primary Completion: 2028-09-01
• Study Completion: 2028-12-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: Female
• Target Recruitment: 211

Inclusion Criteria

• Informed consent to participate
• 18-40 years old
• First pregnancy
• Singleton pregnancy (confirmed through ultrasound)
• No current PLPP
• Dutch- or English speaking

Exclusion Criteria

• Pregnant for more than 16 weeks
• Currently experiencing PLPP, or having had PLPP during the index pregnancy
• History of surgery or major trauma to spine, pelvis or legs
• Specific vestibular or balance disorders
• Use of medication that could affect balance (e.g., ototoxic or centrally-acting drugs)
• Specific spinal conditions or deformities (e.g., structural scoliosis)
• Rheumatic disease
• (History of) a neurological disorder (e.g., neuropathy)
• Problems with vision that are not corrected by glasses, contact lenses or surgical eye correction
• Hyperemesis gravidarum
• Recent history of ankle problem (e.g., ankle sprain less than 3 weeks ago)
• Currently having a condition that may compromise the normal course of the pregnancy (e.g., hypertension, renal disease, coagulation disorder)
• Use of corticosteroids or NSAIDs
• (History of) endocrine, nutritional, metabolic, inflammatory, (auto)immune, cardiovascular conditions, or cancer
• Comorbidities that might influence inflammatory markers (e.g., acute illness, infection (e.g. CMV, HPV, urinary tract infection...), hypothyroidism, endometriosis)
• (History of) psychiatric disorder

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Primary Outcome Measures

Name	Time	Method
Pregnancy-related lumbopelvic pain (PLPP) (primiparous women)	Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The presence of PLPP will be questioned at each timepoint. PLPP will be defined as: "self-reported pain in the lumbar area, between the twelfth rib and the gluteal fold, with or without pain between the posterior iliac crest and the gluteal fold, particularly in the vicinity of the sacroiliac joints, that may radiate to the posterior thigh and could occur separately or in conjunction with pain in the symphysis pubis."
Depression, anxiety and stress in general with the Depression Anxiety Stress Scale (DASS-21) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The DASS-21 evaluates depressive mood, anxiety and stress in general: 21 items, total score per subscale (Depression, Stress, Anxiety) range 0 - 21. Higher scores indicate higher levels of depressive mood (DASS-21-Depression), anxiety (DASS-21-Anxiety) and stress (DASS-21-Stress).
Pregnancy-related anxiety with the Revised Pregnancy-related Anxiety Questionnaire (PRAQ-R2) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36)	The PRAQ-R2 evaluates pregnancy-related anxiety: 10 items, total score range 10 - 50. Higher scores indicate higher levels of pregnancy-related anxiety.
Body perception at the lumbar spine will be assessed with the Fremantle Back Awareness Questionnaire (FreBAQ) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The FreBAQ assesses back-specific body perception: 9 items, total score range 0 - 45. Higher score indicate a more disturbed body perception.
Postural control (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Upright standing balance control will be measured as center-of-pressure displacements with a force plate.
Proprioceptive use during postural control (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Center-of-pressure displacements in response to ankle muscle and lower back muscle vibration (60 Hz, 15s) during upright standing will be measured with a force plate.
Inflammation with blood samples (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Serum concentrations of inflammatory mediators will be measured.
Task related fear of movement (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Participants will be first asked to list three tasks (i.e., movements or activities) they fear to perform with regard to their low back or pelvic girdle. Subsequently, for each of the three tasks, they will be asked to rate their (1) pain intensity, (2) perceived harmfulness, (3) fear, and (4) self-efficacy to perform the task, all via a Visual Analogue Scale (VAS) with 0= no pain/harmfulness/fear or maximum self-efficacy to 100= maximal pain/harmfulness/fear or minimum self-efficacy.
The ability to cope in a stressful situation with the Sense of Coherence Scale (SOC-13) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The SOC-13 contains 13 items, total score ranges 0 - 91.
Pregnancy-related depression with the Edinburgh Depression Scale (EDS) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The EDS evaluates perinatal depression: 10 items, total score range 0 - 30. Higher scores indicate higher levels of pregnancy-related depression.
Catastrophic thinking related to pain with the Pain Catastrophizing Scale (PCS) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The PCS contains 13 statements on thoughts and emotions possibly related to the experience of pain, for which the participants rates her agreement: 13 items, total score range 0 - 52. Higher scores indicate higher levels of pain catastrophizing.
Body perception at the lumbar spine will be assessed with a laterality recognition task ("Recognise Back" app) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	During the laterality recognition task, participants view 40 pictures of a model that has its lower back bent or rotated to the left or the right side. They will be asked to judge the direction of movement as quickly and accurately as possible. Average speed (in seconds) of response time and average accuracy of the answers (in %) will be recorded.

Secondary Outcome Measures

Name	Time	Method
Pain intensity of PLPP with Visual Analogue Scale (VAS) (primiparous women)	Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The participants will be asked to rate the pain intensity at the lower back or pelvic girdle they experience at this moment (i.e., both at the start and the end of the full test procedure), the average pain intensity during the past week, the minimal pain intensity during the past week, and the maximal pain intensity during the past week, by using the Visual Analogue Scale (VAS, 0-100), with 0 = "no pain" and 100 = "the worst pain imaginable".
Pain frequency of PLPP (Primiparous women)	Timepoint 1 Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The participants will be asked how often they experience pain (1= some days, 2= most days, 3= every day)
Pain location of PLPP with a body chart (primiparous women)	Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Individuals with PLPP will indicate the pain locations on a body chart.
Current body weight (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	Current body weight will be measured (kg)
Disability due to PLPP with the Modified Oswestry Disability Index (mODI) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The ODI is a 10-item self-report questionnaire that quantifies the extent of functional limitation in daily life due to low back pain. Each item is given a score between 0 (no limitation) and 5 (maximal limitation). The sum of the scores is multiplied by 2 to obtain a percentage score, with higher scores representing greater functional disability
Disability due to PLPP with the Quebec Back Pain Disability Scale (QBPDS) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The QBPDS assesses disability in individuals with low back pain and PLPP: 20 items, total score range 0 - 100. Higher scores indicate higher levels of disability.
Health-related quality of life with the 36-Item Short Form Health Survey (SF-36) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The SF-36 evaluates health-related quality of life, 8 scales: physical functioning, role physical, bodily pain, general health, vitality, social functioning, role emotional, and mental health. Scores for the different scales are converted and pooled using a scoring key, for a total score ranging 0 - 100
Fear avoidance beliefs with the Fear-Avoidance Beliefs Questionnaire (FABQ) (primiparous women)	Timepoint 1 (between gestational weeks 9-14), Timepoint 2 (between gestational weeks 32-36), Timepoint 3 (6 weeks postpartum), Timepoint 4 (9 months postpartum)	The FABQ consists of 16 statements for which the participant rates her agreement with the statement on a scale from 0 ("completely disagree") to 6 ("completely agree"): 16 items, total score range 0 - 96). Higher scores on the FABQ indicated more strongly held fear-avoidance beliefs.

Trial Locations

Locations (2)

Hasselt University; 🇧🇪 Hasselt, Belgium

KU Leuven; 🇧🇪 Leuven, Belgium