Anatomy & Body Systems
Affected Body Systems
Understanding the complex anatomy of the sacroiliac region is essential for proper diagnosis and treatment:
- Skeletal System : Sacrum (S1-S5 vertebrae fused), ilium (pelvic bone), coccyx
- Articular System : Sacroiliac joints (left and right), sacrococcygeal joint
- Ligamentous System : Anterior sacroiliac ligament, posterior sacroiliac ligament, interosseous sacroiliac ligament, sacrotuberous ligament, sacrospinous ligament
- Muscular System : Gluteus maximus, gluteus medius, gluteus minimus, piriformis, erector spinae, quadratus lumborum, psoas major, iliacus
- Nervous System : L4-S3 nerve roots, sciatic nerve, superior gluteal nerve, obturator nerve
- Vascular System : Internal iliac artery, superior gluteal artery, lateral sacral arteries
System Interconnections: The sacroiliac joints serve as the primary link between the axial skeleton (spine) and the appendicular skeleton (legs). These joints must accommodate the mechanical demands of walking, running, lifting, and sitting while maintaining pelvic stability. The extensive ligamentous network and muscular support create a sophisticated biomechanical system. When one component is compromised, cascading effects occur throughout the kinetic chain.
Healers Clinic Integrative View: At Healers Clinic, we recognize that sacroiliac dysfunction often reflects broader patterns of musculoskeletal imbalance. Our NLS Screening (Service 2.1) can identify functional energetic imbalances affecting the pelvic region. The Ayurvedic Assessment evaluates Vata dosha involvement and the health of Asthi (bone) and Majja (bone marrow) dhatus. Homeopathic constitutional assessment considers the whole person, recognizing that chronic pelvic dysfunction often correlates with constitutional patterns and miasmatic influences.
| Structure | Location | Function | Relevance to SI Dysfunction |
|---|---|---|---|
| Sacrum | Base of spine, between hip bones | Weight transmission, pelvic stability | Primary site of dysfunction; triangular bone formed by 5 fused vertebrae |
| Ilium | Upper pelvic bone | Weight-bearing, muscle attachment | Forms SI joint with sacrum; largest part of pelvis |
| SI Joints | Between sacrum and ilium | Shock absorption, weight transfer | Source of pain when dysfunctional; limited but crucial motion |
| Piriformis | Deep gluteal muscle | Hip external rotation | Can compress sciatic nerve, mimic SI pain |
| Gluteus Maximus | Buttock | Hip extension, external rotation | Primary pelvic stabilizer; key for standing from sitting |
| Gluteus Medius | Lateral buttock | Hip abduction, pelvic stability | Critical during single-leg stance; often weak in SI dysfunction |
| Quadratus Lumborum | Lower back | Lateral pelvic stability | Often tight with SI dysfunction; connects pelvis to spine |
| Psoas Major | Deep hip flexor | Hip flexion, lumbar stability | Can affect pelvic alignment when tight |
| Erector Spinae | Along spine | Spinal extension | Supports lumbar spine; often compensates for weak glutes |
| Iliolumbar Ligament | L5 to ilium | SI joint stability | Important stabilizer; can be source of pain when stressed |
Deep Anatomical Considerations:
The sacroiliac joints are unique in several ways. Unlike most joints in the body, they are not designed for extensive movement. The sacrum is wedged between the two iliac bones, and the irregular joint surfaces (called facets or auricular surfaces) interlock like puzzle pieces. This shape provides inherent stability while still allowing minimal motion essential for childbirth and shock absorption during walking.
The ligaments surrounding the SI joints are exceptionally strong and numerous. The anterior sacroiliac ligament is relatively thin, while the posterior sacroiliac ligament is thick and strong, forming the main stability structure. The interosseous sacroiliac ligament, located deep between the ilium and sacrum, is considered the primary stabilizer.
Blood supply to the SI joint comes from the gluteal and iliolumbar arteries. Innervation is complex, with contributions from the L4-S2 nerve roots. This complex innervation explains why SI joint pain can sometimes be difficult to localize and may refer pain to distant areas.
Types & Classifications
By Mechanism:
- Traumatic : Resulting from acute injury (falls, motor vehicle accidents, birth trauma)
- Mechanical : From repetitive stress, poor posture, or movement patterns
- Inflammatory : From conditions like ankylosing spondylitis, psoriatic arthritis, or enteropathic arthritis
- Degenerative : From osteoarthritis or degenerative joint disease
- Pregnancy-related : From hormonal changes and mechanical stress during pregnancy
- Idiopathic : No identifiable cause
By Motion Abnormality:
- Hypermobility (Instability) : Excessive movement causing pelvic instability
- Hypomobility (Fixation) : Restricted movement causing stiffness and compensatory strain
- Combination : Elements of both hypermobility and hypomobility in different planes
By Duration:
- Acute : Less than 6 weeks, often from injury
- Subacute : 6-12 weeks
- Chronic : More than 12 weeks, may involve degenerative changes
By Severity:
- Mild : Intermittent pain with specific activities
- Moderate : Regular pain affecting daily activities
- Severe : Constant pain with significant functional limitation
Causes & Root Factors
Traumatic Causes:
- Falls : Landing on buttocks or side. Direct impact to the buttocks or lateral hip can bruise the SI joint, damage supporting ligaments, or cause micro-fractures. Falls from height or on slippery surfaces are common causes.
- Motor Vehicle Accidents : Impact injuries to pelvis. The force of a collision can cause significant trauma to the pelvis, including SI joint injury, even without fractures.
- Sports Injuries : Direct blows, twisting injuries. Contact sports, gymnastics, and activities involving twisting motions place significant stress on the SI joints.
- Birth Trauma : During delivery, especially with difficult labor. The SI joints naturally relax during childbirth to allow for delivery, but excessive force or instrumental delivery can cause injury.
- Workplace Injuries : Lifting accidents, falls. Repetitive lifting, especially with poor technique, can gradually stress the SI joints and supporting structures.
Mechanical Causes:
- Leg Length Discrepancy : Asymmetric pelvic loading
- Poor Posture : Prolonged sitting, uneven standing
- Repetitive Activities : Running, climbing, heavy lifting
- Improper Lifting : Using back instead of legs
- Sedentary Lifestyle : Weak core and pelvic muscles
Hormonal/Physiological Causes:
- Pregnancy : Relaxin hormone loosens ligaments
- Menstruation : Hormonal fluctuations affect ligamentous laxity
- Menopause : Hormonal changes affecting joint stability
Inflammatory Causes:
- Autoimmune Conditions : Ankylosing spondylitis, psoriatic arthritis
- Infections : Septic arthritis (rare)
- Degenerative Changes : Osteoarthritis
- Previous Lower Back Injury : Altered biomechanics
- Occupation : Jobs requiring prolonged standing or lifting
- Athletic Activities : Running, gymnastics, dance
- Obesity : Increased mechanical stress on pelvis
- Weak Core Muscles : Insufficient pelvic support
- Tight Hip Muscles : Altered pelvic mechanics
- Emotional Stress : Muscle tension, guarding
- Ayurvedic perspective : Vata dosha aggravation causing dryness and degeneration in Asthi Dhatu (bone tissue), weak Majja Dhatu (bone marrow), accumulation of ama (toxins) in the pelvic region, and disturbed Apana Vata (downward-moving energy). The condition often correlates with Vata-Pitta or Vata-Kapha constitutional types.
- Homeopathic perspective : Constitutional predisposition, miasmatic influence (sycotic/psoric), suppressed emotions affecting musculoskeletal tissues, inherent weakness in connective tissue. Chronic SI dysfunction often relates to the tubercular or sycotic miasm.
- Physiotherapy perspective : Muscle imbalances (tight hip flexors, weak glutes), sacroiliac joint hypomobility or hypermobility, trigger points in gluteal and piriformis muscles, altered gait patterns, postural dysfunction, and asymmetrical loading patterns.
- Naturopathic perspective : Nutritional deficiencies (Vitamin D, calcium, magnesium), systemic inflammation, poor tissue healing, gut inflammation affecting nutrient absorption, and hormonal imbalances affecting joint stability.
Risk Factors
- Age : Peak incidence 20-50 years
- Gender : Women 2x more likely than men
- Genetics : Family history of ankylosing spondylitis or autoimmune conditions
- Previous Pelvic Injury : History of falls or trauma
- Pregnancy History : Multiple pregnancies increase risk
- Occupation : Jobs requiring heavy lifting or prolonged standing. Healthcare workers, construction workers, and others who spend long hours on their feet or lift heavy objects are at increased risk.
- Exercise Habits : Repetitive high-impact activities. Runners, dancers, and athletes who engage in repetitive impact activities can develop SI joint dysfunction over time.
- Posture : Sitting or standing with poor alignment. Prolonged sitting with poor posture, especially with a wallet in the back pocket, can create asymmetries that stress the SI joints.
- Strength : Weak core and pelvic floor muscles. Insufficient strength in the core stabilizers forces the SI joints and ligaments to bear more load than they are designed for.
- Flexibility : Tight hip muscles. Limited flexibility in the hip flexors, hamstrings, or rotators can alter pelvic mechanics and increase stress on the SI joints.
- Body Weight : Obesity increases mechanical stress. Excess weight places additional load on the SI joints during weight-bearing activities, accelerating wear and tear.
- Stress Levels : Chronic tension affects muscle patterns. Emotional stress often manifests as muscle tension in the hips, pelvis, and lower back, contributing to SI joint dysfunction.
- Healthcare workers (nurses, physiotherapists)
- Construction workers
- Farmers and agricultural workers
- Athletes (runners, gymnasts, dancers)
- Office workers (prolonged sitting)
- Warehouse workers
- Delivery personnel
- Pregnant Women : Up to 50% experience pelvic girdle pain
- Postpartum Women : 20-30% develop persistent pelvic pain
- Athletes : Especially runners, gymnasts, and contact sport athletes
- Elderly : Degenerative changes increase susceptibility
Signs & Characteristics
Pain Location:
- One or both sides of lower back (below waistline)
- Buttocks (usually one side, can be bilateral)
- Groin and inner thigh
- Lateral hip
- Posterior thigh (to knee)
- Rarely: Lower abdomen
Pain Quality:
- Dull, aching pain to sharp, stabbing
- Deep, gnawing sensation
- Often worse in the morning
- May improve with movement
- Can be constant or intermittent
Aggravating Activities:
- Standing for prolonged periods
- Walking (especially stairs)
- Climbing stairs
- Lifting heavy objects
- Bending forward
- Transitioning from sitting to standing
- Rolling in bed
- Sexual intercourse
Relieving Factors:
- Lying down (especially on unaffected side)
- Sitting with proper support
- Using a pillow between knees when sleeping
- Heat application
- Gentle movement
- Gradual onset : More common than acute onset
- Unilateral pain : Often affects one side more
- Morning stiffness : Improves with movement
- Activity-related : Pain increases with weight-bearing
- Night pain : Can disturb sleep, especially when rolling
- Antalgic gait: Shortened stance phase on affected side
- Trendelenburg sign: Pelvic drop when standing on one leg
- Difficulty with stair climbing
- Pain with single-leg stance
Associated Symptoms
- Lower back stiffness (especially morning)
- Hip pain (may radiate to groin)
- Gluteal pain and tenderness
- Leg pain (posterior thigh, occasionally to calf)
- Numbness or tingling (rare, suggests nerve involvement)
- Pelvic instability feeling
- Difficulty with balance activities
- Pain during intercourse
- Urinary or bowel symptoms (rare, requires evaluation)
Symptoms that are NOT characteristic of simple sacroiliac dysfunction:
- Pain above the waistline (suggests lumbar spine)
- Pain radiating below the knee (suggests nerve root involvement)
- Numbness in a dermatomal pattern
- Bilateral symptoms without clear cause
- Morning stiffness lasting more than one hour
- Systemic symptoms (fever, weight loss, night sweats)
- Lumbar Disc Herniation : Pain radiates below knee, associated numbness
- Hip Osteoarthritis : Pain in groin, limited internal rotation
- Ankylosing Spondylitis : Morning stiffness >30 minutes, improves with exercise
- Piriformis Syndrome : Pain with sitting, sciatica symptoms
- Kidney Disease : Flank pain, urinary symptoms
- Infection : Fever, severe pain, systemic symptoms
Clinical Assessment
Initial Consultation (Service 1.1/1.2):
- Detailed history of complaint
- Onset and progression of pain
- Activities that aggravate/alleviate symptoms
- Previous injuries or trauma
- Occupation and daily activities
- Menstrual history (for women)
- Previous treatments tried
- Associated symptoms review
- Medical and surgical history
- Family history
Physical Examination:
- Visual inspection (posture, pelvic alignment, gait)
- Palpation of SI joints, sacrum, surrounding muscles
- Active range of motion testing
- Special provocation tests:
- FABER test (Flexion, Abduction, External Rotation)
- Gaenslen's test
- Compression test
- Distraction test
- Thigh thrust test -侧卧屈髋测试 (Side-lying hip flexion test)
- Neurological screening (reflexes, sensation, strength)
- Hip examination (to rule out hip pathology)
- Lumbar spine screening
Differential Diagnosis:
- Rule out lumbar spine involvement
- Assess for hip joint pathology
- Consider inflammatory conditions
- Evaluate for neurological involvement
Diagnostics
Clinical Diagnosis
Sacroiliac joint dysfunction is primarily a clinical diagnosis based on history and physical examination. No single test definitively confirms SI joint pain, so diagnosis relies on clusters of positive findings.
- X-ray : Rule out fracture, dislocation, degenerative changes, sacroiliitis
- CT Scan : Detailed assessment of joint anatomy
- MRI : Evaluate soft tissues, inflammation, stress fractures
- Bone Scan : Detect inflammation or infection
Specialized Diagnostic Injections
- Diagnostic Block : Local anesthetic injection into SI joint (gold standard)
- Provocative Angiography : For vascular assessment if indicated
Healers Clinic Specialized Diagnostics
- NLS Screening (Service 2.1) : Bioenergetic assessment to identify functional imbalances
- Ayurvedic Pulse Diagnosis (Service 4.4) : Constitutional evaluation and dosha assessment
- Constitutional Homeopathic Assessment (Service 3.1) : Individual remedy selection based on totality
- Gut Health Analysis (Service 2.3) : If inflammatory component suspected
Differential Diagnosis Tests
- Blood Tests : Rule out inflammatory conditions (ESR, CRP, HLA-B27)
- Hip X-ray : Rule out hip pathology
- Lumbar MRI : If neurological symptoms present
Differential Diagnosis
| Condition | Key Differentiating Features |
|---|---|
| Lumbar Disc Herniation | Pain below knee, dermatomal numbness, positive straight leg raise |
| Hip Osteoarthritis | Groin pain, limited internal rotation, morning stiffness <30 min |
| Ankylosing Spondylitis | Morning stiffness >30 min, improves with exercise, young males |
| Piriformis Syndrome | Sciatica symptoms, pain with sitting, positive FAIR test |
| Greater Trochanteric Pain Syndrome | Lateral hip pain, tender trochanter |
| Myofascial Pain | Trigger points, taut bands in muscles |
| Sacroiliitis | Inflammatory pain, positive inflammatory markers |
Red Flags
- Severe pain not responding to treatment
- Weight loss
- Fever or chills
- Night pain not relieved by position change
- History of cancer
- Progressive neurological symptoms
- Bowel or bladder dysfunction
Conventional Treatments
- Rest : Avoid aggravating activities initially
- Ice/Heat : Ice for acute pain, heat for muscle tightness
- NSAIDs : Ibuprofen, naproxen for pain and inflammation
- Activity Modification : Avoid heavy lifting, prolonged standing
- Proper Ergonomics : Chair height, standing posture
- Manual Therapy : Joint mobilization, soft tissue techniques
- Targeted Exercises : Gluteal strengthening, core stabilization
- Stretching : Hip flexors, piriformis, hamstrings
- Pelvic Stabilization : Specific SI joint stabilization exercises
- Gait Training : Correct compensatory patterns
- Postural Education : Sitting, standing, lifting techniques
- Modalities : TENS, ultrasound as needed
- Corticosteroid Injections : Reduce inflammation in and around joint
- Prolotherapy : Injection to promote ligamentous tightening
- Radiofrequency Ablation : For chronic pain relief
- Surgery : Very rare, only for severe instability or failed conservative care
- NSAIDs for pain and inflammation
- Muscle relaxants for muscle spasm
- Neuropathic pain medications if nerve involvement
Integrative Treatments
Constitutional remedies selected based on totality of symptoms:
- Rhus tox : Joint stiffness worse with initial movement, better with continued motion
- Bryonia : Joint pain worse with any movement, wants to be still
- Arnica : Bruised, sore feeling, fear of being touched
- Ruta : Bone and periosteum pain, overuse injuries
- Causticum : Joint weakness, stiffness, worse in cold damp weather
- Kalmia : Shooting pains, worse with motion
- Symphytum : Bone and tendon injuries, non-union fractures
- Hypericum : Nerve-rich area pain, shooting pains
- Aesculus : Pelvic congestion, dull aching in sacrum
- Sepia : Bearing-down sensations, pelvic weakness
- Abhyanga : Therapeutic oil massage to lower back and pelvis (Service 4.2)
- Marma Therapy : Specific marma points for pelvic pain (Service 4.4)
- Kati Basti : Localized oil treatment for sacral region (Service 4.4)
- Panchakarma : Detoxification therapies for systemic balance (Service 4.1)
- Herbal Medications : Ashwagandha, Guggulu, Shallaki, Ginger
- Dietary Modifications : Anti-inflammatory foods, Vata-pacifying diet
- Lifestyle Counseling : Activity modification, proper sleep posture
- Manual Therapy : Joint mobilization, myofascial release (Service 5.1)
- Stabilization Exercises : Core and pelvic floor strengthening (Service 5.2)
- Targeted Stretching : Hip flexors, piriformis, hamstrings
- Gait Training : Correct compensatory patterns
- Ergonomic Assessment : Workplace modifications
- Advanced Techniques : Dry needling, shockwave if indicated (Service 5.5)
- Gentle Asanas : Child's pose, cat-cow, pigeon pose
- Core Strengthening : Modifications for pelvic stability
- Breathwork (Pranayama) : For pain management and relaxation
- Restorative Sequences : For chronic pain management
- Progressive Implementation : Based on individual capacity
- Traditional Points : GB30, BL36, BL40, BL57 for sacral pain
- Regional Points : Local and distal points for pain relief
- Ear Acupuncture : For chronic pain management
- Trigger Point Injections : For associated myofascial pain
- Prolotherapy : For ligamentous laxity
- Comprehensive Approach : Combining multiple modalities
Self Care
- Rest : Avoid activities that cause pain
- Ice : 15-20 minutes, several times daily to painful area
- Heat : For muscle tightness, after initial acute phase
- Over-the-counter Pain Relievers : NSAIDs as directed
- Gentle Movement : Avoid complete rest; gentle walking
- Maintain Activity : Continue gentle activities; avoid prolonged rest
- Sleep Position : Side-lying with pillow between knees
- Sitting Posture : Proper chair height, lumbar support
- Standing Habits : Shift weight periodically, avoid locked knees
- Heat Before Activities : Warm-up for stiffness
- Ice After Activities : If painful afterward
Piriformis Stretch:
- Lie on back
- Cross affected ankle over opposite knee
- Pull bottom leg toward chest
- Hold 30 seconds
- Repeat 3 times
Hip Flexor Stretch:
- Kneel on one knee
- Step other foot forward
- Push hips gently forward
- Hold 30 seconds each side
Gluteal Bridges:
- Lie on back, knees bent, feet flat
- Lift hips toward ceiling
- Hold 5 seconds
- Lower slowly
- Repeat 10-15 times
Clamshells:
- Lie on side, knees bent
- Keep feet together
- Lift top knee toward ceiling
- Hold 5 seconds
- Repeat 10-15 times each side
Bird Dog:
- On hands and knees
- Extend opposite arm and leg
- Hold 5 seconds
- Repeat 10 times each side
Prevention Strategies
- Maintain Core Strength : Regular core stabilization exercises
- Proper Lifting Technique : Bend at knees, not waist
- Ergonomic Workstation : Proper chair and desk height
- Balanced Activity : Avoid overtraining
- Strengthen Glutes : Prevent pelvic instability
- Manage Stress : Chronic tension affects muscle patterns
Prevention
Primary Prevention
- Core Strengthening : Regular exercise targeting core and pelvic muscles
- Proper Posture : Sitting and standing with correct alignment
- Ergonomic Workstation : Proper setup for desk work
- Balanced Exercise Program : Include strength, flexibility, and cardio
- Proper Lifting Techniques : Use legs, not back
- Adequate Warm-up : Before physical activities
Workplace Prevention
- Chair Selection : Ergonomic chair with proper lumbar support
- Regular Movement : Take breaks from prolonged sitting
- Standing Techniques : Shift weight, avoid locked knees
- Desk Ergonomics : Monitor height, keyboard position
- Job-Specific Training : Proper techniques for physical work
Sports-Specific Prevention
- Gradual Progression : Increase training intensity slowly
- Strength Training : Include hip and core exercises
- Flexibility Work : Regular stretching routine
- Proper Technique : Sport-specific movement patterns
- Adequate Recovery : Rest between intense sessions
Pregnancy-Specific Prevention
- Pelvic Floor Exercises : Strengthen support structures
- Hip-Strengthening : Prepare for increased load
- Posture Awareness : As pregnancy progresses
- Supportive Footwear : Reduce pelvic stress
- Movement Modifications : As needed during pregnancy
When to Seek Help
- Severe pain following injury or accident
- Inability to bear weight
- Signs of infection (fever, severe pain, redness)
- Numbness or weakness in legs
- Bowel or bladder dysfunction
- Unexplained weight loss with pain
- Pain lasting more than 2-3 weeks
- Pain not improving with self-care
- Pain interfering with work or daily activities
- Recurring episodes of SI pain
- Uncertainty about diagnosis
- Previous treatment not effective
- Pain during or after pregnancy
Prognosis
Expected Outcomes
- 78% improve with comprehensive treatment at Healers Clinic
- Most patients recover within 3-6 months with appropriate treatment
- Early intervention leads to faster recovery
- Some may have persistent symptoms requiring ongoing management
- Recurrence is possible but can be minimized with maintenance exercises
- Week 1-2 : Acute phase, focus on pain control and gentle movement
- Week 2-6 : Begin targeted exercises, manual therapy
- Week 6-12 : Progressive strengthening, functional training
- Month 3-6 : Return to activities gradually, maintenance program
- Ongoing : Continue stabilization exercises, address contributing factors
Factors Affecting Prognosis
- Positive Factors : Early treatment, good compliance with exercises, strong support system
- Negative Factors : Chronic pain >6 months, significant trauma, inflammatory conditions, poor adherence to treatment
FAQ
Q: Can sacroiliac joint dysfunction heal on its own? A: Mild cases often improve with rest and activity modification within weeks. However, seeking professional treatment can speed recovery, prevent chronic problems, and address underlying causes. Without proper treatment, the condition may recur or become chronic.
Q: How do I know if my pain is from the SI joint? A: SI joint pain typically causes pain below the waistline, in the buttocks, groin, or lateral hip. Pain worsens with weight-bearing activities like standing, walking, or climbing stairs, and improves with lying down. Physical examination with specific provocation tests can help confirm the diagnosis.
Q: Does sacroiliac joint dysfunction require surgery? A: Rarely. More than 95% of cases improve with conservative treatment including physiotherapy, medication, and lifestyle modifications. Surgery is only considered after 6-12 months of failed conservative care for severe instability.
Q: How long does it take to recover from SI joint dysfunction? A: Most people improve within 3-6 months with appropriate treatment. Acute cases may resolve in 4-8 weeks, while chronic cases may take longer. Our integrative approach at Healers Clinic achieves 78% improvement rates.
Q: Can I exercise with sacroiliac joint dysfunction? A: Yes, but modifications are needed. Avoid high-impact activities initially and focus on gentle exercises that don't aggravate symptoms. Our physiotherapy team (Service 5.1) can design a safe exercise program appropriate for your condition.
Q: Is SI joint dysfunction the same as sciatica? A: No, but they can have similar symptoms. Sciatica refers to compression of the sciatic nerve, usually from a lumbar disc herniation. SI joint dysfunction causes pain from the sacroiliac joint itself. They can coexist, so proper diagnosis is important.
Q: Can pregnancy cause sacroiliac joint dysfunction? A: Yes, pregnancy is a common cause. Hormonal changes during pregnancy relax the ligaments supporting the SI joints, which can lead to instability and pain. Up to 50% of pregnant women experience some form of pelvic girdle pain. Our integrative approach is safe and effective during and after pregnancy.
Q: What is the best treatment for sacroiliac joint dysfunction? A: Evidence supports a combination of targeted physiotherapy (especially stabilization exercises), activity modification, and pain management. Our integrative approach combining physiotherapy, homeopathy, Ayurveda, and acupuncture provides comprehensive care addressing both symptoms and root causes.