The Role of the Iliopsoas Muscle in Low Back Pain

Low back pain is one of the most common health problems encountered today, both clinically and socially. Although the etiology of low back pain is often multifactorial, the condition of specific muscle groups within the musculoskeletal system (particularly the iliopsoas muscle) plays a critical role in spinal health. When evaluating our patients and developing treatment plans, we meticulously consider the anatomical and functional characteristics of the iliopsoas muscle.

Anatomical and Functional Importance of the Iliopsoas Muscle

The iliopsoas muscle is formed by the union of the psoas major and iliacus muscles and serves as the primary hip flexor. It also functions as a stabilizer of the lumbar spine. Proper function of this muscle directly affects the biomechanics of the lumbosacral spine and pelvic region.

In our clinical practice, we observe the following:

• Chronic low back pain patients frequently present with tightness or dysfunction of the iliopsoas muscle.
• Shortening of the muscle may lead to pelvic tilt and alterations in lumbar lordosis, thereby exacerbating pain.
• Weakness of the iliopsoas compromises spinal stabilization, increasing mechanical load on intervertebral discs and facet joints.

Therefore, assessing both strength and flexibility of the iliopsoas muscle is a fundamental step in patient evaluation.

Iliopsoas Muscle Dysfunction in Low Back Pain

Dysfunction of the iliopsoas muscle may contribute to low back pain in several ways:

1. Shortening and Tightness: Prolonged sitting, poor posture, or a sedentary lifestyle may cause shortening and increased tension of the iliopsoas muscle. This leads to anterior pelvic tilt and increased lumbar lordosis, resulting in chronic low back pain.
2. Weakness: When the muscle is weak, mechanical load on the spine increases. When we identify iliopsoas weakness in our patients, we consider that low back pain may originate solely from muscular dysfunction.
3. Coordination Impairment: Since the psoas muscle is critical for balance and movement coordination during gait, dysfunction may lead to overuse of compensatory muscles, causing widespread pain.

During clinical examination, we obtain detailed information about the condition of the iliopsoas muscle using methods such as the Thomas test, Modified Thomas test, and hip flexion strength testing.

Pain Mechanisms of the Iliopsoas Muscle

The contribution of the iliopsoas muscle to low back pain occurs on both mechanical and neurophysiological levels:

• Mechanical Effect: A shortened muscle creates abnormal force vectors on the spine, leading to excessive loading of facet joints and intervertebral discs.
• Neurophysiological Effect: Accumulation of lactic acid and muscle spasms increase local inflammation and exert pressure on neural structures, triggering pain.

By explaining this mechanism in detail to our patients, we help them understand that the muscle is not merely weak or tight but plays an active role in the development of pain.

Assessment and Clinical Tests

When evaluating our patients, we systematically examine the following aspects:

• Postural Analysis: Pelvic tilt, lumbar lordosis, and postural abnormalities.
• Flexibility Tests: Thomas test and Modified Thomas test to assess iliopsoas length and flexibility.
• Strength Tests: Hip flexion strength and isometric psoas activation.
• Functional Tests: Gait analysis, stair climbing, and squat movements to evaluate the muscle’s role in daily activities.

Based on these assessments, we individualize both manual therapy and exercise programs for our patients.

Treatment Approaches

Treatment plans for patients with iliopsoas muscle dysfunction generally include the following components:

a) Manual Therapy

• Deep tissue massage and myofascial techniques aimed at reducing muscle tension.
• Pelvic and lumbar mobilization techniques.

b) Osteopathy

• Osteopathic approaches that evaluate biomechanical imbalances within the musculoskeletal system and aim to restore balance through manual techniques may be particularly effective in iliopsoas-related low back pain.
• We aim to improve muscle function through osteopathic manipulation, fascial mobilization, regulation of viscerosomatic reflexes, and optimization of pelvic alignment.
• Because this approach targets both mechanical and neurophysiological factors, it can significantly enhance treatment outcomes.

c) Exercise Programs

• Flexibility Exercises: Lunge, bridge, and psoas stretching exercises to improve muscle length and range of motion.
• Strengthening Exercises: Strengthening hip flexors and stabilizing muscles, particularly in coordination with core musculature.
• Functional Exercises: Daily movement patterns and activities to improve muscle coordination and endurance.

d) Postural and Ergonomic Education

• Educating patients to minimize prolonged sitting and poor posture, and providing ergonomic recommendations.

e) Holistic Approach

• Recognizing that low back pain is not solely muscle-related, we adopt a multidisciplinary approach when necessary, combining physiotherapy, pain management, medical treatment, and lifestyle modifications.

Conclusion

We clearly observe that the iliopsoas muscle plays a critical role in low back pain from both mechanical and neurophysiological perspectives. By targeting muscle dysfunction through early diagnosis, accurate assessment, and individualized exercise programs, we can reduce pain, improve mobility, and enhance our patients’ quality of life.

When we apply a holistic and multidisciplinary approach without neglecting the role of the iliopsoas muscle, we can significantly increase the success rate of conservative treatment in low back pain.

Asst. Prof. Elif Berber
Specialist in Physical Medicine and Rehabilitation