SIJ blockage

What does SIJ blockage mean?

The term “SIJ blockage” is a common expression for complaints that arise from the sacroiliac joint. In medical terms, it is more precisely referred to as an ISG dysfunction or an ISG syndrome. The joint is not really dislocated, but rather its function is disturbed due to muscular-fascial tension, joint irritation, incorrect loading or changes in the ligament system. This can lead to pain, a feeling of “locking” and limited mobility.

• Common cause of deep-seated lumbar/buttock pain
• Pain often unilateral, but can occur bilaterally
• Triggers include: Incorrect loading, microtrauma, instability or irritation

Anatomy: Understanding the sacroiliac joint

The ISG connects the sacrum (os sacrum) with the pelvic blades (os ilium). It is a tightly guided, articulated connection system with little mobility. Stability is created primarily by strong ligaments (including the sacroiliac ligament), the fascia and the surrounding muscles (gluteal muscles, deep trunk and pelvic floor muscles).

• Function: Power transmission between torso and legs
• Movement: Only a few degrees of rotation/gliding - but very resilient
• Sources of pain: joint capsule, ligaments, adjacent muscles/fascia

Typical symptoms of an SIJ blockage

The symptoms are characteristic, but not always clear. Some patients show a typical “Fortin sign”: a clearly defined pain point is shown with the finger just below the edge of the pelvis, near the middle buttock region.

• Deep, one-sided pain in the buttocks or next to the sacrum
• Radiating to the groin, hip, side of the thigh or rarely to the knee
• Reinforcement when sitting for long periods of time, standing up, turning in bed, climbing stairs
• Feeling of instability or “locking” in the pelvis
• Stiffness in the morning, improved by exercise or warmth

Neurological deficits (e.g. deafness, paralysis) are atypical with an SI joint block. If such signs occur, other causes must be clarified.

Causes and risk factors

SI joint dysfunction usually occurs as a result of an interaction between stress, muscular balance and the ligament system. Everyday life and work often involve long periods of sitting, repetitive lifting or sports with rotational/jumping stress.

• Muscular imbalances: weak core/gluteal muscles, tense piriformis
• Incorrect or overloading: sitting for long periods of time, asymmetrical activities, carrying things on one side
• Leg length difference, foot misalignment, scoliosis (changed statics)
• Pregnancy/breastfeeding: hormonal ligament loosening, pelvic ring strain
• Previous falls/trauma to the pelvic/lumbar spine area
• Hypermobility syndromes (e.g. weak connective tissue)
• Inflammatory causes (spondyloarthritis/sacroiliitis) – less common but important to recognize

Diagnostics: This is how we proceed

Diagnosis is based on a careful history and physical examination. There are special provocation tests that are often positive for sacroiliac joint pain. The sum of several tests results in a high level of significance.

• Provocation tests (e.g. thigh thrust, compression/distraction, Gaenslen, FABER/Patrick, sacral thrust)
• Fortin finger test (point pain just below the edge of the pelvis)
• Functional testing of hips, lumbar spine, pelvic stability and muscles

Imaging is primarily used to rule out other causes and for special questions: X-ray (pelvis/lumbar spine) to assess the bony structures, ultrasound for soft tissue diagnosis, MRI if inflammation, stress reaction or alternative sources of pain are suspected. Targeted diagnostic infiltration of the SIJ using imaging can confirm the source of pain in individual cases.

Warning signs (fever, pain at night when resting, significant neurological deficits, weight loss, known tumor disease) require rapid clarification.

Differentiation: What can look similar?

• Lumbar disc herniation (radicular pain, sensory/motor loss)
• Facet joint syndrome of the lumbar spine
• Hip osteoarthritis or hip labral lesion
• Trochanteric pain syndrome (bursal irritation on the outside of the hip)
• Piriformis syndrome
• Spondyloarthritis (inflammatory sacroiliitis, e.g. Bechterew's disease)

Conservative therapy: The evidence-based step-by-step plan

Most SIJ problems can be treated without surgery. The aim is to relieve pain, reduce irritation and sustainably improve pelvic/torso stability. The approach is tailored to the individual – depending on the cause, duration and severity of the symptoms.

• Education & activity adjustment: Rest in the acute stage, but early functional, adapted exercise instead of bed rest
• Physiotherapy with a focus on lumbopelvic stability (deep trunk/gluteal muscles, hip control, pelvic floor coordination)
• Manual therapy to mobilize hypomobile segments and relax myofascial trigger points
• Warmth/cold: Warmth for muscle relaxation, cold for acute irritation
• Analgesics/anti-inflammatory drugs for a short period of time (e.g. paracetamol, possibly NSAIDs - after individual risk-benefit assessment)
• Taping/pelvic belt (SI belt) v. a. in case of instability, pregnancy/breastfeeding
• Ergonomics coaching: lifting with the legs, distributing loads, changing seats, workplace optimization

Relaxation and breathing techniques can also be helpful in reducing protective muscular tension. A rapid increase in physical exertion should first be avoided and rebuilt in a structured manner.

Exercises and self-help: Start safely

Gentle, regularly performed exercises support stability and reduce the risk of relapse. Important: Movements should be painless. If symptoms increase, signs of nerve irritation or uncertainty occur, please seek medical advice.

Initially practice 3-4 times a week, later a combination of strength, mobility and endurance (e.g. brisk walking, cycling). Individual adjustment through physiotherapy increases safety and effect.

Targeted infiltration and other options

If consistent conservative measures are not effective enough, targeted infiltration of the sacroiliac joint can be considered. It is used both therapeutically (anti-inflammatory/pain relief) and – in selected cases – diagnostically.

• SIJ infiltration under imaging (ultrasound or fluoroscopy) with local anesthetic ± low-dose corticosteroid
• Trigger point or myofascial infiltrations with pronounced muscle involvement
• Radiofrequency therapy of the lateral branches: only for chronic, confirmed SIJ pain after previous successful test injections and conservative therapy has been exhausted
• Surgical sacroiliac joint fusion: rare last resort in specialized centers when all conservative/interventional options have been exhausted

Regenerative procedures (e.g. PRP/Prolotherapy) are discussed; the evidence is heterogeneous. If used at all, it is used after careful indication and explanation of the benefits and limitations.

Course and prognosis

The prognosis for SI joint dysfunction is usually good. Many affected people benefit from education, targeted physiotherapy and everyday adjustments within weeks. It is crucial to recognize the triggering factors (e.g. ergonomic errors, training deficits) and address them sustainably.

• Acute courses: often resolves within 2–6 weeks
• Subacute/chronic courses: structured rehabilitation program, if necessary additional infiltrations
• Relapse prevention: continuous stabilization exercises, load control, checking habits

Prevention and everyday tips

• Regular strength and stability training for the core and hips
• Active breaks during sedentary work, adjust the workplace ergonomically
• Lift loads close to your body, distributing weight on both sides
• Suitable footwear, pay attention to leg axis and foot statics
• During pregnancy: early pelvic stabilization, if necessary lap belt
• Gradual training build-up after breaks - no jumps in scope/intensity

When should you seek medical advice?

Seek medical advice if the pain is severe, new, recurring or persistent - especially if there are restrictions in everyday life or sports.

• Immediate clarification for: symptoms of numbness/paralysis, bladder/rectal disorders
• Fever, night sweats, unexplained weight loss
• Severe night pain, accident/trauma, risk of osteoporosis
• Known tumor disease or suspected inflammatory rheumatic disease

Orthopedics in Hamburg: Your way to us

Our practice at Dorotheenstraße 48, 22301 Hamburg, is centrally located and easily accessible. We value a careful clinical examination, evidence-based, primarily conservative treatment and clear, understandable information. Interventions are only considered after non-surgical options have been meaningfully exhausted.