Managing Sacroiliac Joint Dysfunction: Diagnosis and Treatment Options

Introduction

Sacroiliac (SI) joint dysfunction is a prevalent source of low back pain, affecting approximately 25% of adults with chronic low back pain. This condition can be particularly challenging to diagnose and treat due to its overlapping symptoms with other forms of back pain. Women, especially those who are pregnant or postpartum, are more susceptible to SI joint dysfunction due to the increased mobility and stress on the SI joint.

Anatomy and Function of the SI Joint

The SI joints are the largest axial joints in the human body, connecting the iliac bones to the sacrum. They serve a critical role in transferring vertical loads from the lumbar spine to the lower extremities and act as shock absorbers during movements. The joints have a limited range of motion, about 2–4 mm in all planes, which decreases further with age due to cartilaginous changes. The SI joint is made up of an anterior one-third that is a true synovial joint, while the posterior two-thirds consist of various ligamentous connections. These ligaments play a vital role in stabilizing the joint and limiting its range of motion.

SI joints undergo various changes with aging. In early adulthood, the joint surfaces are smooth and allow for multidirectional gliding motions. Age-related changes begin during puberty and continue throughout life. The SI joint is covered by two different cartilages. The concave sacral surface is covered with a thick hyaline articular cartilage that reaches 4 mm in thickness by adulthood. The convex iliac surface is lined by a thin fibrocartilage. These morphological changes restrict motion and accelerate during the third decade. Further changes resemble osteoarthritic degeneration and include surface irregularities, fissures, chondrocyte clustering, and fibrillation.

Pathophysiology of SI Joint Dysfunction

SI joint dysfunction arises from abnormal motion or malalignment of the joint. This can be due to hypermobility (excessive movement) often seen in pregnancy due to hormonal changes or hypomobility (restricted movement) resulting from trauma or a sedentary lifestyle. Abnormal motion places undue stress on the joint and surrounding structures, leading to pain and dysfunction.

Hypermobility and Hypomobility:

• Hypermobility is commonly observed in pregnant women due to increased production of estrogen and relaxin, which lead to ligamentous laxity. The growing fetus also adds stress to the joint, further increasing the risk of dysfunction.
• Hypomobility can result from pelvic fractures, degenerative changes, or a sedentary lifestyle, leading to joint fixation and restricted movement.

Malalignment and Abnormal Motion:

• Malalignment of the SI joint, often caused by trauma or improper biomechanics during activities, can lead to increased stress on the joint and surrounding structures.
• Abnormal Motion includes conditions where the joint moves excessively (hypermobility) or insufficiently (hypomobility). Both scenarios can cause pain and dysfunction by altering the normal load distribution across the pelvis and spine.

Mechanical and Inflammatory Factors:

• Mechanical Factors: These include heavy lifting, falls, motor vehicle accidents, and sports activities that involve repetitive stress on the SI joint. These activities can cause ligamentous strains, joint inflammation, and microtraumas, leading to chronic pain.
• Inflammatory Factors: Conditions such as ankylosing spondylitis and other spondyloarthropathies can cause inflammation of the SI joint, leading to pain and stiffness. These inflammatory conditions often present with systemic symptoms and can be identified through specific laboratory tests.

Degenerative Changes:

• Degenerative changes in the SI joint, such as osteoarthritis, can occur with aging. These changes include cartilage degradation, formation of osteophytes, joint space narrowing, and sclerosis. These alterations can lead to chronic pain and reduced joint mobility.

Clinical Presentation and Diagnosis

Patients with SI joint dysfunction typically present with pain localized to the lower back, buttocks, lateral hip, and occasionally the lower extremities. Pain is often unilateral or bilateral but rarely midline. Activities such as standing from a seated position, climbing stairs, or lying on the affected side can exacerbate the pain. SI joint dysfunction is commonly misdiagnosed due to its overlapping symptoms with other forms of low back pain.

Differential Diagnosis

Differentiating SI joint dysfunction from other causes of low back pain requires a thorough history and physical examination. Conditions that share similar symptoms with SI joint dysfunction include:

• Femoral Acetabular Impingement (FAI): FAI typically presents with hip pain, which can be exacerbated by activity or prolonged sitting. Patients may experience joint locking or clicking. The pain is usually located in the groin area but can radiate to the buttocks and thigh, making it difficult to distinguish from SI joint pain.

• Fractures: Pelvic or sacral fractures, often resulting from trauma or osteoporosis, can mimic SI joint dysfunction. These fractures are usually identified through imaging techniques such as X-rays or CT scans. A detailed history of trauma or sudden onset of severe pain can help differentiate these fractures from SI joint dysfunction.

• Infection: Infections like osteomyelitis or septic arthritis of the SI joint can present with fever, malaise, and intractable pain. These conditions are often accompanied by elevated inflammatory markers (e.g., ESR, CRP) and require prompt medical intervention. A history of recent infections or immunocompromised status may raise suspicion for an infectious cause.

• Ischiofemoral Impingement: This condition is characterized by pain in the gluteal or hip region, often associated with hip snapping and a shortened stride. The pain is usually exacerbated by hip extension and external rotation. Physical examination maneuvers that reproduce the pain can help differentiate it from SI joint dysfunction.

• Lumbar Disc Herniation: Patients with lumbar disc herniation may present with numbness, tingling in the legs or feet, lower extremity weakness, and radiating pain that follows a dermatomal pattern. Bowel or bladder changes may also be present in severe cases. MRI is the diagnostic modality of choice to visualize disc herniations.

• Lumbar Facet Syndrome: Older adults are more commonly affected by lumbar facet syndrome, which presents with paraspinal muscle tenderness and pain that worsens with backward bending. Imaging may show degenerative changes in the facet joints.

• Piriformis Syndrome: This condition involves compression of the sciatic nerve by the piriformis muscle, leading to sitting intolerance and radiating pain along the posterior of one or both legs. Physical examination maneuvers such as the FAIR (Flexion, Adduction, and Internal Rotation) test can help diagnose piriformis syndrome.

• Pudendal Nerve Irritation: Pudendal nerve irritation causes perineal or scrotal pain and sitting intolerance. The pain may be neuropathic in nature, with burning or tingling sensations. A detailed neurological examination and history of pelvic surgeries or trauma can aid in diagnosis.

• Spondyloarthropathies: Conditions like ankylosing spondylitis may present with chronic inflammatory back pain, morning stiffness, and improved symptoms with exercise. Laboratory tests such as HLA-B27 and imaging studies showing sacroiliitis can support the diagnosis.

• Tumors: Malignancies involving the pelvis or spine can present with focal bone pain and pathologic fractures. These cases may also be associated with unexplained weight loss, night sweats, and systemic symptoms. Imaging studies and biopsy may be required for definitive diagnosis.

Differentiating SI joint dysfunction from these conditions requires a comprehensive approach, incorporating patient history, physical examination, imaging studies, and sometimes laboratory tests. Utilizing at least three out of five positive provocation tests (Gaenslen, thigh thrust, distraction, compression, and sacral thrust) is recommended to assist in diagnosing SI joint dysfunction. This recommendation is based on consistent results from prospective and blinded validity trials.

Physical Examination

A comprehensive physical examination is crucial in diagnosing SI joint dysfunction. Key components include:

• Observation: Look for asymmetric iliac crest height and asymmetric weight-bearing when standing.
• Gait Analysis: Note any painful catching or increased pain ipsilaterally during the stance phase and decreased hip extension resulting in shortened contralateral stride length.
• Provocation Tests: Use tests such as the Gaenslen, thigh thrust, distraction, compression, and sacral thrust tests. Positive responses to at least three of these tests suggest SI joint dysfunction. Using at least three out of five positive provocation tests (Gaenslen, thigh thrust, distraction, compression, and sacral thrust) is recommended to assist in diagnosing SI joint dysfunction. This recommendation is based on consistent results from prospective and blinded validity trials.
• Strength Testing: Assess gluteus medius weakness.
• Flexibility: Check for iliopsoas and piriformis tightness, hamstring tightness with gluteal weakness.
• Palpation: Pain at or inferomedial to the posterior superior iliac spine.

Activities That May Aggravate Pain

Certain activities can exacerbate pain associated with SI joint dysfunction, including:

• Ascending or descending stairs
• Jogging uphill
• Landing after jumping
• Lying on the affected side
• Prolonged sitting in a car
• Prolonged standing
• Shifting weight to the affected side
• Turning in bed

Treatment Options

Conservative Management

1. Medications: NSAIDs are commonly used for pain relief. Although there are no studies comparing the use of NSAIDs to other treatments for SI joint dysfunction, they are effective for both acute and chronic low back pain. NSAIDs may be beneficial as part of a multimodal treatment approach. This recommendation is based on expert opinion and accepted practice standards.
2. Physical Therapy: Programs focusing on pelvic girdle stabilization, stretching, and manipulative therapy are beneficial. Exercises should target the iliopsoas, piriformis, gluteal muscles, and the abdominal core. Physical therapy exercise programs have demonstrated intermediate and long-term benefits. Family physicians can facilitate the use of these programs by providing education on iliopsoas and piriformis stretching. Physical therapy exercise programs, SI joint manipulation, or a combination of both should be considered as first-line treatment options. This is based on consistent results from randomized controlled trials and practice recommendations from in-depth reviews.
3. Pelvic Belts: These can help stabilize the joint in pregnant or postpartum patients. Pelvic belts may assist in stabilizing SI joint motion and reducing ligament strain for peripartum patients with SI joint dysfunction.

Interventional Treatments

1. Intra-articular Injections: Corticosteroids or local anesthetics can provide temporary relief. Intra-articular corticosteroid injections are beneficial in treating sacroiliitis or other inflammatory conditions. These injections help reduce inflammation and provide pain relief by delivering medication directly to the joint space. Confirmation of SI joint pain can be made by an image-guided anesthetic block to the SI joint. This method is supported by systematic reviews identifying the diagnostic accuracy of SI joint injections.
2. Radiofrequency Ablation: This technique involves applying radiofrequency energy to disrupt nerve signals, providing longer-term pain relief. Cooled radiofrequency ablation of the L4 and L5 medial branch and lateral sacral branches is beneficial in patients with a positive response to a diagnostic SI joint block. Radiofrequency ablation works by creating a thermal lesion on the nerves supplying the SI joint, interrupting the pain signals and providing relief for several months.
3. SI Joint Fusion: Surgical fusion may be considered for patients who do not respond to conservative or interventional treatments. Patients who do not report improvement in pain symptoms after conservative and less invasive interventions may benefit from surgical fusion of the SI joint. This procedure involves fusing the SI joint to provide stability and reduce pain by eliminating abnormal motion.

Conclusion

Sacroiliac joint dysfunction is a significant contributor to low back pain and requires a comprehensive approach to diagnosis and treatment. Understanding the underlying pathophysiology and employing a combination of conservative and interventional therapies can lead to effective management and improved patient outcomes.

Incorporating the key recommendations for practice, such as the use of multiple provocation tests and image-guided anesthetic blocks, can enhance diagnostic accuracy and treatment efficacy. Furthermore, a multidisciplinary approach involving medications, physical therapy, and interventional procedures ensures a holistic and patient-centered strategy in managing SI joint dysfunction.

References

1. Newman, David P., and Adam T. Soto. "Sacroiliac joint dysfunction: diagnosis and treatment." American Family Physician 105.3 (2022): 239-245.
2. Gartenberg, Ariella, Adam Nessim, and Woojin Cho. "Sacroiliac joint dysfunction: pathophysiology, diagnosis, and treatment." European Spine Journal 30 (2021): 2936-2943.