LOWER CROSS SYNDROME-RELATED MUSCULOSKELETAL IMPAIRMENTS IN PATIENTS WITH LOW BACK PAIN: A CROSS-SECTIONAL ANALYTICAL STUDY

Abstract

Background: Low back pain (LBP) is a common musculoskeletal condition that may be associated with alterations in lumbopelvic muscle strength, muscle length, and pelvic alignment. Lower Cross Syndrome (LCS) describes a pattern of muscular imbalance involving weakness of selected abdominal and gluteal muscles together with shortening or tightness of hip-flexor and lumbar musculature. The present study investigated the relationship between LCS-related musculoskeletal characteristics and diagnosed LBP.

Objective: To determine the relationship between Lower Cross Syndrome and low back pain and to assess pelvic alignment, selected muscle tightness, and muscle strength among patients diagnosed with LBP.

Methods: A cross-sectional analytical study was conducted in the Physiotherapy Department of Pakistan Railway Hospital, Rawalpindi, Pakistan, from November 2024 to May 2025. Patients aged 15–55 years with diagnosed LBP were recruited using purposive sampling according to predefined eligibility criteria. Data were collected using a self-structured questionnaire incorporating demographic characteristics, Numeric Pain Rating Scale (NPRS), assessment of pelvic tilt, muscle length, and manual muscle testing. Iliopsoas, rectus femoris, and thoracolumbar muscle characteristics were assessed, while abdominal, gluteus maximus, and gluteus medius strength was evaluated using manual muscle testing. Data was analyzed using SPSS version 25. Categorical variables were presented as frequencies and percentages, continuous variables as mean ± standard deviation, and associations were assessed using the Chi-square test. Statistical significance was set at p<0.05.

Results: The reported mean age of participants was 38.2 ± 6.22 years, with a male-to-female ratio of 2:1. Eighty-two percent were married and 41.3% were housewives. An NPRS score of 5 was reported by 60% of participants, while approximately 38.1% reported a recent episode of LBP within the preceding 4–6 months. More than 65% demonstrated a lordotic lumbar curve and 50% demonstrated anterior pelvic tilt. Iliopsoas shortening was observed in all assessed participants, with 76.2% demonstrating more than 20° shortening. Thoracolumbar muscle tightness was present in 61.9%. Reduced abdominal, gluteus maximus, and gluteus medius strength was frequently observed, with only approximately 12%, 12.7%, and 11.1%, respectively, demonstrating normal strength. Significant associations were reported between several muscle characteristics and age, marital status, and occupation, whereas gender was not significantly associated with muscle length or muscle strength.

Conclusion: LCS-related musculoskeletal impairments, including iliopsoas shortening, thoracolumbar tightness, reduced abdominal and gluteal muscle strength, anterior pelvic tilt, and lordotic lumbar posture, were frequently observed among patients with diagnosed LBP. These findings support the clinical assessment of muscle length, muscle strength, and pelvic alignment as components of the physical therapy examination of patients with LBP. However, the cross-sectional design does not establish a causal relationship between LCS-related impairment and LBP. Further longitudinal and controlled studies are required to clarify the temporal and causal relationship between these muscular characteristics and low back pain.