Psoas Strain

Lower Limb

Overview

Psoas strain is an acute or chronic injury to the psoas major muscle, typically resulting from excessive hip flexion, rapid acceleration-deceleration movements, or prolonged postural stress. This condition commonly affects athletes, desk workers, and individuals with altered lumbopelvic biomechanics. Pain is typically deep in the lower abdomen or groin with potential radiation into the anterior thigh.

Pathophysiology

The psoas major muscle originates from the lateral aspects of the T12-L5 vertebral bodies and intervertebral discs, passing through the pelvis to insert on the lesser trochanter of the femur. Strain occurs when muscle fibres are overstretched or experience excessive eccentric loading, particularly during hip flexion against resistance or rapid hip extension. Microtears lead to inflammatory response, haematoma formation, and subsequent muscle guarding. Chronic strain may result from sustained hip flexion postures (desk work, driving) creating adaptive shortening and increased tension. The muscle's deep anatomical position and proximity to visceral structures can complicate diagnosis and create referred pain patterns.

Patient Education

Psoas strain typically improves with relative rest, hip flexor stretching, and gradual return to activity; early movement within pain tolerance promotes healing better than complete immobilisation.

Typical Presentation

Site

Deep lower abdomen, groin, anterior hip crease; may radiate along anterior thigh to knee; symptoms often unilateral but can be bilateral with postural causes

Quality

Deep aching, sharp catching sensation with movement, constant dull ache with acute strain; may feel like abdominal discomfort or groin strain

Intensity

Acute strain: moderate to severe pain limiting hip flexion and walking; chronic strain: mild to moderate persistent ache worsening with activity

Aggravating

Seated hip flexion (desk work, driving), walking uphill, running or sprinting, rapid hip extension movements, direct abdominal pressure, lying supine with hips extended

Relieving

Prone lying or side-lying positions, hip flexion (knees drawn toward chest), gentle stretching, heat application, anti-inflammatory medications, osteopathic treatment

Associated

Limited hip flexion range of motion, anterior hip tightness, lower back pain, pelvic asymmetry, lumbar lordosis increase, altered gait pattern, hip flexor weakness on contralateral side, possible abdominal wall tension

Orthopaedic Tests

Test descriptions are written with AI assistance from standard clinical texts. Where a test lists Sources, its description has been checked against them; those sources are independent and do not endorse OsteoKit. Accuracy figures and grades (A–D) appear only when checked against the published study; tests without one are marked “No accuracy study”.

Further reading: full test procedures are described in standard clinical examination texts, e.g. Magee & Manske, Orthopedic Physical Assessment (7th ed.), and Cook & Hegedus, Orthopedic Physical Examination Tests: An Evidence-Based Approach (2nd ed.).

No accuracy study

Thomas Test

Procedure

Patient sits at the end of the plinth, then lies back hugging one knee to the chest. The other leg hangs down. Look at the position of the hanging thigh, and repeat on the other side.

Positive Finding

The hanging thigh rises above the plinth, or passive extension of the hip reproduces pain in the groin or lower abdomen.

Interpretation

Shows hip flexor length. Pain with the stretch supports iliopsoas involvement; tightness alone is common and does not diagnose a strain.

Sources

No accuracy study

Thomas Test with Overpressure

Procedure

In the Thomas position, gently press the hanging thigh down towards the floor, keeping the knee bent and the other knee hugged to the chest.

Positive Finding

Reproduction of the patient's own groin or lower abdominal pain.

Interpretation

Adds a passive stretch to iliopsoas. Pain supports iliopsoas involvement. Do not force the stretch in an acute injury.

No accuracy study

Side-Lying Hip Extension Stretch

Procedure

Patient lies on the unaffected side, bottom knee bent for balance. Hold the pelvis steady and take the top leg gently back into hip extension.

Positive Finding

Pain in the groin or lower abdomen, or less extension than on the other side.

Interpretation

Stretches the hip flexors. Pain supports iliopsoas involvement. Not a validated test.

No accuracy study

Palpation of Psoas (Supine)

Procedure

Patient supine with the knees bent and the abdomen relaxed. Press gently and slowly into the abdomen just lateral to the rectus abdominis, below the level of the navel, then ask the patient to lift the leg slightly to feel the psoas tighten. Also palpate the tendon below the inguinal ligament, lateral to the femoral artery pulse.

Positive Finding

Deep tenderness that reproduces the patient's own pain.

Interpretation

Supports psoas involvement. Palpation through the abdomen is uncomfortable and imprecise. Stop if you feel a strong pulse (aorta or iliac artery) or a mass, and ask about bowel, bladder or gynaecological symptoms, as abdominal and pelvic organs can refer pain to this area.

Sources

No accuracy study

Resisted Hip Flexion (Seated or Supine)

Procedure

Patient sitting on the edge of the plinth. Ask the patient to lift the knee above 90° of hip flexion and hold against your downward resistance.

Positive Finding

Pain in the groin or lower abdomen, or weakness compared with the other side.

Interpretation

Holding hip flexion above 90° mainly loads iliopsoas. Pain supports an iliopsoas injury.

Sources

No accuracy study

Resisted Straight Leg Raise

Procedure

Patient supine. Ask the patient to lift the straight leg a little off the plinth, then hold it against your downward resistance above the knee.

Positive Finding

Pain in the groin or lower abdomen, or weakness.

Interpretation

Loads the hip flexors. Pain supports a hip flexor injury but does not separate psoas from rectus femoris. Groin pain with this test can also come from the hip joint. (Pace's test is a piriformis test and does not apply to the psoas.)

Sources

⚠ Red Flags

  • •Severe sudden onset with inability to walk suggesting complete muscle rupture
  • •Unilateral lower limb swelling and warmth suggesting deep vein thrombosis
  • •Fever and progressive systemic symptoms suggesting psoas abscess or infection
  • •Acute urinary retention or bowel dysfunction suggesting cauda equina compression
  • •Unexplained weight loss with persistent groin symptoms suggesting malignancy
  • •Severe unrelenting night pain suggesting serious underlying pathology

⚡ Yellow Flags

  • •Excessive work-related prolonged sitting without postural support
  • •Fear-avoidance beliefs about hip flexion causing hypervigilance and guarding
  • •High catastrophising about abdominal symptoms confusing diagnosis with visceral pathology
  • •Overtraining without adequate recovery in athletic population
  • •Poor body awareness and proprioception contributing to chronic strain
  • •Maladaptive coping strategies (complete immobilisation rather than graduated activity)

Osteopathic Techniques

No trials of osteopathic or manual techniques for psoas strain were found. For iliopsoas problems, a reference chapter puts stretching, strengthening and changes to training first.

Region

Psoas and iliopsoas complex

Technique

Soft tissue, hip and thighNo trials found

Rationale

Hands-on work to the hip and thigh muscles to ease tension and pain, given alongside exercise.

How it's done & evidence

How it's done

Hands-on kneading, stretching and sustained pressure to the muscles around the hip and thigh: the hip flexors, adductors and hamstrings, and tensor fasciae latae with the iliotibial band.

Evidence in Psoas Strain

Searched 24 Oct 2026: no trials of psoas soft tissue technique in psoas strain.

Sources

Region

Psoas and iliacus

Technique

Muscle energy, psoasNo trials found

Rationale

Low-force, patient-powered stretch for a tight psoas and iliacus.

How it's done, cautions & evidence

How it's done

The hip is taken into extension to the barrier (prone, or supine with the leg off the table). The patient pulls the hip toward flexion for 3–5 seconds against equal resistance, relaxes, and the hip is taken further into extension. Repeat 3–5 times, then re-check.

Cautions

Do not use with a fracture in the area, an unstable pelvis or hip, recent surgery, or a patient who cannot contract on request or follow directions.

Evidence in Psoas Strain

Searched 24 Oct 2026: no trials of psoas MET in psoas strain.

Region

Lumbar spine and lumbosacral junction

Technique

Articulation, lumbarNo trials found

Rationale

Gentle, rhythmic mobilisation of the lower back and pelvis to ease stiffness.

How it's done, cautions & evidence

How it's done

Rhythmic, low-velocity movement of restricted lumbar segments within their passive range, with no thrust, usually side-lying or prone. The amplitude can vary.

Cautions

Side effects reported in trials were mild and short-lived: soreness, tiredness or a flare of existing symptoms.

Evidence in Psoas Strain

Searched 24 Oct 2026: no trials of lumbar mobilisation in psoas strain.

Sources

Region

Pelvic girdle and sacroiliac joints

Technique

Articulation, sacrum (sacral rocking)No trials found

Rationale

Gentle sacral rocking to ease sacroiliac and pelvic tension.

How it's done, cautions & evidence

How it's done

Patient prone, both hands over the sacrum. The practitioner follows the sacrum with the breath and adds slight pressure at the end of each breath to exaggerate its motion. Continue for 2–3 minutes or until the tissues release, then re-check.

Cautions

Stop if it causes pain. Do not use with cancer near the sacrum, infection or inflammation, cauda equina syndrome, bone disease of the spine, or bony joint instability.

Evidence in Psoas Strain

Searched 24 Oct 2026: no trials of sacroiliac articulation in psoas strain.

Rehabilitation Exercises

Supine Hip Flexor Stretch (Pectineus and Psoas)

StretchingBeginner

Kneeling Hip Flexor Lunge Stretch

StretchingBeginner

Supine Figure-Four Stretch (Piriformis and Hip External Rotators)

StretchingBeginner

Supine Hip Flexion and Extension (Pendulum Motions)

Range of MotionBeginner

Glute Bridge (Hip Extensor Activation)

StrengtheningBeginner

Quadruped Hip Extension (Glute Activation)

StrengtheningBeginner

Supine Pelvic Tilt and Transversus Abdominis Engagement

PosturalBeginner

Sidelying Hip Abduction (Hip Stabilisers)

StrengtheningIntermediate

Single-Leg Glute Bridge (Unilateral Hip Stability)

StrengtheningIntermediate

Standing Hip Flexor Stretch with Contralateral Lean

BalanceIntermediate

Prone Hip Extension with Knee Bent (Isolated Psoas Loading)

StrengtheningIntermediate

Plank Hold with Hip Neutral Positioning (Core Stability)

PosturalAdvanced

Referral Criteria

  • •Inability to bear weight or walk suggesting complete muscle rupture or severe acute strain requiring imaging (MRI/ultrasound)
  • •Unilateral leg swelling with warmth and possible calf symptoms suggesting deep vein thrombosis requiring urgent vascular assessment
  • •Fever, severe systemic illness, or signs of infection suggesting psoas abscess requiring medical imaging and possible antibiotics
  • •Acute cauda equina syndrome presentation (bilateral leg pain, bowel/bladder dysfunction, saddle anaesthesia) requiring immediate neurosurgical evaluation
  • •Persistent severe night pain unresponsive to conservative treatment suggesting malignancy or serious pathology requiring imaging and oncology referral
  • •Neurological signs (progressive weakness, sensory loss, reflex changes) suggesting nerve compression requiring neurology or neurosurgery assessment
  • •No improvement after 6-8 weeks of conservative treatment requiring advanced imaging (MRI) to exclude structural pathology or surgical consultation
  • •Concurrent abdominal symptoms (nausea, vomiting, altered bowel function) suggesting possible visceral involvement requiring medical evaluation
  • •History of significant trauma with severe initial pain and imaging findings of complete muscle rupture potentially requiring surgical intervention