Sacroiliac Joint Injury

Updated: Dec 06, 2023
Author: Andrew L Sherman, MD, MS; Chief Editor: Sherwin SW Ho, MD 

Overview

Practice Essentials

Most of the US population will have low back pain at some point in their lifetime, with up to about a quarter of the population experiencing it within the past 3 months.[1]  In addition, lower back pain is one of the most prevalent sports maladies, affecting athletes in nearly every sport. Diagnosing the cause of a back injury is quite difficult and challenging because multiple structures in the lower back region can cause pain. However, an accurate diagnosis is paramount to providing successful treatment of the spine injury.

Although still somewhat controversial, the sacroiliac joint (SIJ) is generally accepted as an anatomic structure within the lumbar complex that if injured can be a cause of lower back pain. Mechanical dysfunction, inflammation, infection, trauma, and degeneration all have been attributed to the SIJ. Once the diagnosis of SIJ injury is established, specifically directed treatment can lead to satisfying results. (See the image below.) This article discusses the diagnosis, management, and rehabilitation of sacroiliac injuries and pain.

Flouroscopically guided sacroiliac joint injection Flouroscopically guided sacroiliac joint injection. Contrast seen throughout the joint.

Epidemiology

United States statistics

The incidence of lower back pain in humans parallels the incidence of the common cold, with a lifetime rate approaching 95%. Goldwaith and Osgood first discussed the possibility that SIJ injury could cause low back pain as early as 1905.[2] In the decades since then, several attempts have been made to establish the prevalence of SIJ syndrome in persons with back pain, and the results of these reports vary widely.

Schwarzer et al remarked that "the prevalence of sacroiliac pain would appear to be at least 13% and perhaps as high a 30%" in patients with low back and buttock pain.[3]  Bernard and Kirkaldy-Willis reported the prevalence rate to be 22.5% in 1293 patients with back pain.[4]

There is a bimodal distribution with two peaks—younger adults following sporting injury and pregnancy and older adults from degeneration. Both genders and people of all races present with SIJ joint dysfunction.[5]

Functional Anatomy

The SIJ is a true diarthrodial joint that joins the sacrum to the ilium in the posterior pelvis.[6, 7, 8] In this joint, hyaline cartilage on the sacral side moves against fibrocartilage on the iliac side. The joint is generally C shaped with 2 lever arms that interlock at the second sacral level. The joint contains numerous ridges and depressions, indicating its function for stability more than motion. However, studies have documented that motion does occur at the joint; therefore, slightly subluxed and even locked positions can occur.[3, 9]  The joint acts as a shock absorber by dissapating vertical forces of the spine and transmits them to the hips and lower extremities.[10]

Stability is provided by the ridges present in the joint and by the presence of generously sized ligaments. The ligamentous structures offer resistance to shear and loading. The deep anterior, posterior, and interosseous ligaments resist the load of the sacrum relative to the ilium. More superficial ligaments (eg, sacrotuberous ligament) react to dynamic motions (eg, straight-leg raising during physical motion). The long dorsal sacroiliac ligament can become stretched in periods of reduced lumbar lordosis (eg, pregnancy).

Many large and small muscles have relationships with these ligaments and the SIJ, including the piriformis, biceps femoris, gluteus maximus and minimus, erector spinae, latissimus dorsi, thoracolumbar fascia, and iliacus. Any of these muscles can be involved with a painful SIJ. As a true joint, the SIJ is a pain-sensitive structure richly innervated by a combination of unmyelinated free nerve endings and the posterior primary rami of L2-S3. The wide possibility of innervation may explain why pain emanation from the joint can manifest in so many various ways, with different and unique referral patterns for individual patients.

The sacrum can move with respect to the ilium in 6 degrees of freedom, although this motion is minimal, and the joint's hypermobility or hypomobility may cause pain emanating from the joint region. Sexual dimorphism exists in the pelvis. Men tend to have a relatively long and narrow pelvis, with a longer and more conical pelvic cavity than that of women. These sex differences also reflect in the biomechanics of the joint: the female SIJ has higher mobility, and more stresses, loads, and pelvis-ligament strains, compared to the male SIJ.[11]

Sport-Specific Biomechanics

The function of the SIJ is to dissipate loads of the torso through the pelvis to the lower extremities and vice versa. The pelvis acts as a central base through which large forces are accepted and dissipated. Although the main role of the joint is to provide stability, the SIJ has limited motion that allows it to dissipate and transfer significant loads and stresses. Studies by Weisel indicate that most movement occurs when rising from the sitting to the standing position. However, the amount of motion is small, making assessment of sacroiliac motion during physical examination quite difficult. Selvik suggested that hyperextension produces the greatest degree of motion (2° on average, with only minimal translation of 0.5-1.6 mm).

If the motion in the pelvis is asymmetric, then dysfunction can occur. Some conditions that cause asymmetric motion include leg-length inequalities, a unilaterally weak lower limb (eg, polio), tight myofascial structures (eg, iliopsoas), and scoliosis. Hip osteoarthritis can lead to leg-length shortening and SIJ pain.

Women may be at increased risk for SIJ problems because their broader pelvises, greater femoral neck anteversion, and shorter limb lengths lead to different, possibly predisposing, biomechanics. In addition, pregnancy often leads to stretching of the pelvis, specifically targeting the sacroiliac ligaments and possibly leading to dysfunction, hypermobility syndromes, and chronic pain.

Innervation

The nerve supply of the SIJ originates from multiple lumbosacral root levels with partial innervation from L2 (anterior joint) to S3 (posterior joint). Because the root innervation can vary so widely, the pain referral patterns from primary sacroiliac pain can also vary. Fortin et al interviewed multiple patients documented to have sacroiliac pain by anesthetizing the joint with lidocaine injections under fluoroscopic guidance.[12, 13] He found referral patterns ranging from localized buttocks pain to frank radicular leg pain and many other descriptions in between.

Referred pain maps from SIJ dysfunction extend in the L5-S1 nerve distributions, commonly seen in the buttocks, groin, posterior thigh, and lower leg with radicular symptoms. However, this pain distribution demonstrates extensive variability among patients and bears strong similarities to discogenic or facet joint sources of LBP.[1]

Anterior innervation of the sacroiliac joint is from the ventral rami of the L5 to S2 nerve roots. The lateral branches of the dorsal rami of the S1 to S3 nerve roots innervate the posterior part.[5]

Pathophysiology

From an anatomical perspective, pathologic changes and injuries specific to different SIJ structures can result in SIJ pain. These changes include, but are not limited to, capsular and ligamentous tension, hypo- or hypermobility, extraneous compression or shearing forces, micro- or macro-fractures, soft tissue injury, and inflammation.[11]  The SIJ becomes unstable when ligamentous laxity occurs, especially the interosseous and posterior ligaments. The primary mechanism of SIJ injury is a combination of axial loading and abrupt rotation.SIJ instability can also be a result of repetitive microtrauma.[10]

Etiology

Many patients state that their pain began spontaneously, whereas others can cite a specific inciting event. Bernard and Kirkaldy-Willis reported that 58% of patients diagnosed with SIJ pain based on clinical examination findings had some inciting traumatic injury.[4]

Many risk factors are associated with lower back pain, and many are directly associated with lumbar disk injury. These include, but are not limited to, smoking, poor physical condition, positive family history, and occupational lifting.

Factors that specifically increase the likelihood of mechanical injury to the SIJ have not been identified. Pregnancy is one particular condition attributed to SIJ dysfunction.

In the authors’ experience, certain biomechanical or muscle length imbalances may ultimately predispose a person to sacroiliac dysfunction and pain. Likely, this is a result of altered gait patterns and repetitive stress to the SIJ and related structures. These conditions exist in persons with leg-length inequality, scoliosis, a history of polio, poor-quality footwear, and hip osteoarthritis.

Other etiologies of SIJ pain may be spondyloarthropathy, infection, and prior lumbar fusion.[5]

Prognosis

Sacroiliac injury has an excellent prognosis for full recovery. Whereas most studies suggest 80% of people with a lower back injury significantly improve within 2 weeks, no scientific studies show any stratification into diagnostic groups (ie, SIJ injury vs disk injury vs piriformis injury).

If the correct diagnosis is made, utilizing a combination of history, multiple physical examination manuevers, and appropriate imaging or diagnostic procedures, a majority of patients can achieve adequate pain relief. In refractory cases, however, minimally invasive SI fusion is an option with variable results and a plethora of techniques utilized for SI fusion.[5]

Complications

Complications arise more from missed alternative causes of back pain than from any mechanical damage to the joint. Systemic conditions (eg, AS, Crohn-related arthritis) can cause future problems. Missed stress fractures to the hip could progress to a complete fracture. Finally, overlooked malignancy is a rare but real possibility.

Other complications can occur in athletes not fully rehabilitated. Muscle imbalances may persist and put the athlete at risk for reinjury or future injury to another structure. Finally, with any back injury, an inherent risk exists that the pain may become chronic. Excessive rest can often lead to adaption of a deconditioned state or sick role. These mechanical spine conditions must be identified early and rehabilitated aggressively to reduce this complication.

Patient Education

Patient education is essential to achieving good outcomes. Patients can be informed that their SIJ pain is considered a benign condition, which, in most cases, improves with time and conservative treatments. Encourage them to resume physical activity as soon as possible to prevent deconditioning. Also encourage them to immediately enlist the help of a physical therapist to assist with therapeutic exercise. Home exercise programs are essential to help prevent reinjury and can be provided by a physician, chiropractor, or physical therapist.

 

Presentation

History

The key element in the diagnosis of sacroiliac dysfunction is pain. Many authors have attempted to define a typical pain pattern associated with the SIJ. Several of these reports describe patients reporting pain in one or both buttocks at or near the posterior superior iliac spine (PSIS). However, pain radiating to the hip, posterior thigh, or even calf has been described.[14]

Patients often relate that pain especially worsens when they have been sitting for long periods or when they perform twisting or rotary motions.

  • Pain quality: The pain is described as a dull ache or sharp, stabbing, or knifelike, can be at rest or with movement.

  • Pain distribution: Reported distributions are the buttocks, back of the thigh, and upper back; it can be unilateral or bilateral.

  • History: Importantly, exclude a history of inflammatory disorders (eg, inflammatory bowel disease, Reiter syndrome).

  • Fevers, weight loss, and pain in the night with night sweats: These are potential red flags for a systemic illness.

  • Pain that is worse in the morning (morning stiffness) and resolves with exercise: This pattern is consistent with an inflammatory disease.

Physical Examination

The reliability of the physical examination findings to diagnose SIJ dysfunction has been addressed in several articles. The usual pattern of examination is discussed, as follows:

  • Inspection often reveals a pelvis with asymmetric height. This finding can be an indication of unilateral restriction in motion of one or both SIJs. Standing flexion testing involves the comparison of the symmetry of motion between the PSIS on the tested side and the S2 spinous process (Gillet test). However, Freburger and Riddle questioned the reliability of examinations between testers.[15]

  • Of paramount importance is to measure the limb lengths to look for inequality, inspect the lumbar spine to look for scoliosis, and rotate the hips to look for motion restriction.

  • Palpation may be the most reliable indication of SIJ pain. The patient usually places a thumb directly onto one particular spot in the dimple of the PSIS (sacral sulcus). The patient can usually precisely reproduce the pain over that one spot (Fortin finger sign).[13]  More diffuse back or buttock and leg pain should prompt the clinician to question the diagnosis of SIJ dysfunction (see Differentials and Other Problems to Be Considered).

  • In terms of range of motion, motion at the joint is incredibly small with translations never exceeding 1.6 mm and an upper limit of 3° in rotations at the SIJ based on studies. Additional studies have found that no differences in ROM between symptomatic and asymptomatic SIJs. (40)

  • Upon neurologic examination, motor strength, sensory examination, and reflexes in the lower extremities should all prove normal. However, sometimes, strength examination proves challenging, and the patient may exhibit weaknesses because of pain inhibition or frank muscle imbalance that developed during episodes of pain and relative inactivity. True neurogenic weakness, numbness, or loss of reflex should alert the clinician to consider nerve root injury or pathology other than a mechanical dysfunction.

  • Perform pain provocation tests.[13, 16, 17, 18, 19]  Distraction can be performed to the anterior sacroiliac ligaments by applying pressure to the anterior superior iliac spine (iliac gapping test). Apply compression to the joint with the patient lying on his or her side. Pressure is applied downward to the uppermost iliac crest (iliac compression test).

    • The goal of the Gaenslen test is to apply torsion to the joint. With one hip flexed onto the abdomen, the other leg is allowed to dangle off the edge of the table. Pressure should then be directed downward on the leg in order to achieve hip extension and stress the SIJ.

    • For the flexion, abduction, and external rotation (FABER or Patrick) test, the examiner externally rotates the hip while the patient lies supine. Then, downward pressure is applied to the knee.

    • In all tests, pain in the typical area raises suspicion for an SIJ lesion.

  • Unfortunately, although systematic, these tests have not proven reliable in controlled studies. Dreyfuss and colleagues studied 12 SIJ tests in relation to fluoroscopically guided SIJ injection.[20]  They were unable to find even one of these tests to be highly sensitive or specific for diagnosing SIJ pain. Hancock et al also published a review on physical examination testing reliability to diagnose SIJ syndrome.[17]

    • Stuber conducted a systematic review of the literature to determine the specificity, sensitivity, and predictive values of such clinical tests of the sacroiliac joint.[16]  According to the author, "the search was conducted using several online databases: Medline, Embase, Cinahl, AMED, and the Index to Chiropractic Literature. Reference and journal searching and contact with several experts in the area was also employed."

    • Stuber concluded that the distraction test, compression test, thigh thrust/posterior shear, sacral thrust, and resisted hip abduction were the only tests to have specificity and sensitivity greater than 60% in at least one study, and that further investigation is warranted to determine which tests or combinations of these tests are the best for diagnosing SIJ dysfunction.

    • Liska conducted a review which supported Stuber's claims that the combination of the distraction test, thigh thrust test, gaenslens, compression and sacral thrust test in combination were above 70% for the sensitivity and specificity and do have value in clinical value in diagnosing SIJ pain if utilized in combination given the limited sensitivity and specifity individually. Given the limited mobility at the joint, assessing SIJ motion is very difficult in clinical practice.[21]

 

DDx

 

Workup

Approach Considerations

It is essential to consider other etiologies for pain around the SIJ, which can primarily be from the hip and other low back etiologies.

Laboratory Studies

In a patient with sacroiliitis, inflammatory origins (eg, ankylosing spondylitis [AS], psoriatic arthritis) must be considered. The following laboratory studies are appropriate when an inflammatory disorder is suspected in a young patient:

  • Complete blood cell (CBC) count

  • Erythrocyte sedimentation rate (ESR)

  • C-reactive protein (CRP) level

  • Antinuclear antibody (ANA) profile

  • Human leukocyte antigen (HLA)-B27 status

  • Rheumatoid factor (RF) value

In patients in whom the pain has become chronic, clinicians need to consider whether the patients may have secondary reactive depression. Testing for hypothyroidism, cortisol abnormalities, or other metabolic or endocrine imbalances may be appropriate as part of the workup for a patient with depression.

Prostate-specific antigen (PSA) testing, serum protein electrophoresis/urine protein electrophoresis, and other laboratory tests used to investigate for malignancy are appropriate for older patients who have not improved with initial care and may have symptoms warranting further investigation.

Imaging Studies

Use of imaging studies when evaluating sacroiliac pathology is a source of controversy among clinicians because whether normal and abnormal radiographic studies can help differentiate symptomatic versus nonsymptomatic patients is unclear. This is probably due to the great variability in joint anatomy among patients. Additional disagreement exists on the significance of inflammatory findings and degenerative findings (sclerosis) being diagnostic of pain within the joint.

The usual SIJ examination is performed using anteroposterior pelvis/lumbar spine radiography. Sclerosis or obliteration of the SIJ can be observed in older patients.

Patients with AS usually have normal radiographic findings; in older patients with this disease, the joint can appear fused.

Specific sacroiliac views superimpose the anterior and posterior joint margins, which may increase the sensitivity for detecting abnormalities. These radiographs are taken at a 25-30° angle to the anteroposterior plane. Joint widening with erosive and sclerotic changes at the bony margins may be suggestive of inflammatory sacroiliitis.

Computed tomography (CT) scanning can often be used to document reactive spurring, sclerosis, or even subluxation. Many clinicians believe reactive spurring is due to prolonged abnormal motion within the joint.

In persons with inflammatory conditions (eg, AS), bone scanning can show enhancement within the SIJ (often bilaterally).

  • Nuclear medicine bone scanning with single photon emission computed tomography (SPECT) can also be used to rule out femur and pelvic stress fractures and most bony metastatic disease.

  • Some clinicians view enhancement observed in the SIJ unilaterally in a patient with suspected SIJ conditions as an indicator of SIJ dysfunction or inflammation. Slipman et al found nuclear imaging under these circumstances to be very low in sensitivity but high in specificity for sacroiliac-mediated pain.[22] Painful SIJs were confirmed with an intra-articular injection of anesthetic. Therefore, bone scanning was of little value in the diagnostic algorithm for SIJ pain.

  • Adding SPECT scanning may increase the sensitivity of nuclear imaging for SIJ injuries when there are contraindications to MRI; however, this has not been studied.

Magnetic resonance imaging (MRI) is not generally used for evaluating the SIJ, although it can be a valuable tool to help exclude disc herniation (especially at L5-S1) as part of the SIJ dysfunction differential diagnosis (see Differentials and Other Problems to Be Considered). MRI can occasionally show inflammatory signs within the SIJ. MRI can also be used to investigate pelvic stress fracture, femoral neck stress fracture, or femoral head avascular necrosis.

Procedures

In brief, image-guided injections are the gold standard to identify sacroiliac joint dysfunction—documenting both the provocation of symptoms when inflated and relief following local anesthetic infiltration.[5]  For discussion of diagnostic and therapeutic SIJ injection, see Acute Phase, Other Treatments.

 

Treatment

Acute Phase

Rehabilitation Program

The first 10 days are considered the acute phase. If symptoms do not resolve, days 10-180 are considered the subacute phase. Pain lasting longer than 6 months is considered the chronic phase.

Physical therapy

Physical therapy focuses on pain control in the acute phase as well as improving the mechanics of the spine, pelvis, and hips and often is one of the initial line treatments.[23]  Modalities such as ultrasonography with or without phonophoresis, deep and superficial heat, and superficial cold treatments can reduce pain. Neural therapies such as deep tissue massage, myofascial release, and muscle energy stretching techniques can also help. Pelvic myofascial stretching in the neutral spine position can be used for immediate, short-term relief of discomfort. By identifying activities that aggravate the condition, the physician or therapist can have the patient avoid these activities.

Medical Issues/Complications

Osteopathic/chiropractic treatment

Although in the acute-phase muscle spasms may prevent frank manipulation, less aggressive techniques such as muscle energy stretching can be very helpful.

Medical complications

Patients may experience difficulty or even worsening symptoms with physical therapy treatments in certain cases. In these patients, reevaluate the diagnosis and consider other diagnostic possibilities (eg, infection, inflammatory disease, malignancy, neural [lumbosacral root] injury). Patients with acute inflammatory disorders or infections should not usually be administered heat treatments. Patients who cannot perform physical therapy may also have a functional component to their disorder or an underlying psychologic disorder, which needs to be addressed.

Medical interventions

Often, oral medications can be quite effective in the acute phase. Nonsteroidal anti-inflammatory drugs (NSAIDs) are used judiciously in this phase, often with good results. In the first 24-72 hours, a muscle relaxant can be quite effective if a myofascial component to the pain is present. Ice can be considered in the first 48-72 hours; then, the typical switch to heat or contrast treatments is warranted.

Oral medication management may change if the pain persists into the subacute and especially the chronic phase. Chronic lower back pain from any source often leads to the development of a cognitive/behavioral component. In such cases, the use of antidepressants, anticonvulsants, and antiarrhythmic topical and oral medications has been reported to benefit certain selected patients. Because the potential benefits of any of these medications is uncertain, their use must be balanced against their potential adverse effects.

Surgical Intervention

Surgical intervention is rarely used for nontraumatic SIJ pain.[6, 24, 25] Surgery is considered only in patients with chronic pain that has lasted for years, has not been effectively treated by other means, and has led to an extremely poor quality of life; the procedure is a fusion across the joint. A randomized, controlled trial by Polly et al found that patients who underwent minimally invasive SIJ fusion with triangular titanium implants achieved greater pain and disability relief at 24-month follow-up than did those who underwent nonsurgical management. The rates of pain and disability improvement for the fusion patients (102 subjects) at 24 months were 82.0% and 65.9%, respectively, compared with less than 10% for both pain and disability in the nonsurgical patients (46 subjects).[26]

Similarly, a randomized, controlled study by Sturesson et al also found better alleviation of pain and disability with SIJ joint fusion with triangular titanium implants than with conservative management. In the fusion patients (52 subjects), the mean lower back pain score had improved by 43.3 points at 6 months, compared with 5.7 points in the conservative treatment group, while the mean disability score had improved by 26 points in the fusion patients, compared with 6 points in the conservative management group.[27]

A study reported that ilio-sacral screws can be safely used to treat sacral fractures and sacroiliac joint injuries in children.[28]

Consultations

Consultation with a rheumatologist is necessary when the possibility of an underlying inflammatory disorder exists. Consultation with a musculoskeletal specialist is often helpful. The musculoskeletal specialist should provide each patient with a functional assessment, can direct nonoperative treatment, and can communicate with the entire treatment team (eg, physical therapists, trainers). Often, a physiatrist (specialist in the field of physical medicine and rehabilitation) can provide a unique, functional-based history and examination that can lead to an accurate diagnosis and a holistic treatment program.

Other Treatment

In the immediate acute phase, treatment consists of pain reduction through pain medications, rest, and avoidance of the inciting activity. Anti-inflammatory treatment with NSAID medications and externally applied ice is often helpful. Recommend the patient return to usual activities as soon as possible, usually within 24-48 hours. Sometimes a local trigger point injection into the muscle can relieve symptoms.[29, 30, 31, 32]

If the pain does not resolve well in the first 2-3 weeks, an intra-articular injection under fluoroscopic guidance should be considered. SIJ injection is frequently performed with a mixture of anesthetic and steroid, as described by Fortin in 1994 and others.[12, 33, 34, 35, 36, 37] When the actual source of the patient’s discomfort is unclear, postinjection pain reduction offers significant diagnostic information. Fluoroscopic guidance is important because, although a local blind injection into the area of maximal pain can be temporarily effective, the needle rarely enters the joint. CT scanning or MRI can also be used to guide injections into the SIJ, with excellent reliability.

Günaydin and colleagues reported that 20 of 31 patients with spondylarthropathy reported subjective improvement after the first SIJ injection of MRI-guided corticosteroid, and 9 of 15 patients reported subjective improvement after the second injection.[35] The improvement lasted for a mean of 8.7 for the first group and 16.1 months for the second group.

Luukkainen and colleagues reported that periarticular injection of methylprednisolone may be effective in the treatment of pain in the region of the SIJ in nonspondyloarthropathy patients from a study of 24 consecutive patients.[38]

Although these studies are promising, they are not randomized, placebo-controlled studies. Therefore, before efficacy can be established, randomized, placebo-controlled studies must be undertaken.

Even if the injections do relieve the patient's pain, the relief from the injections alone is very often short-lived. Therefore, using the injections only as part of an interdisciplinary rehabilitation program is important. The pain relief offers a window of opportunity to increase the rehabilitation. The point in the course of recovery when a second or even third injection should be attempted is unclear. Most clinicians wait 2-4 weeks before proceeding with a repeat injection.  The decision guiding addition intra-articular injections after the first are determined by the amount of relief obtained from prior injection. If < 50% relief is experienced, no subsequent injections are recommended. If >50% relief is experienced following the first injection, a second administration would be considered. Following a second administration, typically >75% relief is expected for further recommendation of a third.[23]

Manipulation has been reported in multiple studies as effective treatment for acute lower back pain. However, studies specifically on SIJ syndrome are less abundant, though Nejati et al mentioned that manipulation is effective for SIJ pain.[39]  The SIJ is accessible to manipulation treatments, and these may be extremely effective. As with other passive modalities, these treatments should be coupled with an extensive active rehabilitative program. Manipulation following intra-articular injection has been reported anecdotally to be beneficial in selected cases. The combination of manipulation and exercise therapy has no greater effect than each therapy individually.[39]

In chronic conditions, some practitioners believe that SIJ pain is due to hypermobility of the joint, which occurs because of laxity in the ligamentous complex. Prolotherapy is a series of saline and glucose injections applied to the SIJ ligaments to cause an inflammatory reaction, which results in scarring and tightening of the ligaments and a reduction in pain. However, no satisfactory outcome investigations have been performed on prolotherapy for this condition. A study at the Veterans Health Administration that investigated prolotherapy for SI joint dysfunction and instability found that a series of 3 prolotherapy injections can be beneficial for functional gains; however, those with no improvement after the first injection may not receive benefit from the series.[40]

A relatively more recent procedure, radiofrequency denervation, has been advocated for the treatment of especially recalcitrant sacroiliac dysfunction.[41, 42] The procedure was thought to be ineffective for SIJ pain because the innervation to the joint is so diffuse. However, in a study by Gevargez and colleagues, the authors reported that 3 months after the procedure, 13 patients (34.2%) were completely free of pain. Twelve patients (31.6%) reported substantial pain reduction, 7 patients (18.4%) had slight pain reduction, and 3 patients (7.9%) had no pain reduction. A meta-analysis of randomized controlled trials found that radiofrequency ablation can be of benefit for up to 1 year; further study regarding this procedure is needed.[43]

Platelet-rich plasma (PRP) is under investigation for SIJ pain, with efficacy being uncertain. Two major prospective trials have indicated that those treated with steroid injections, compared with PRP, found no significant difference between the two groups at 3 months. Additionally, there have been case reports indicating improvement of pain at 1 year with PRP at the SIJ. Large-scale prospective studies are needed to elucidate the efficacy of PRP.[23]

Recovery Phase

Rehabilitation Program

Physical therapy

The recovery phase cannot proceed without an active, aggressive rehabilitation program. Often, SIJ injury leaves patients with significant deconditioning and muscle imbalances. These functional muscular deficits were sometimes present before the injury and may have predisposed the patient to injury. Some muscles are known to be functioning in a tight or shortened position, such as the hip flexors, hamstrings, tensor fascia lata, obturator internus, and rectus femoris. Other muscles are weak or inhibited, such as the gluteal and abdominal muscles.

Begin physical therapy by correcting any mechanical or leg-length asymmetries (eg, orthotic/shoe lift), stretching overly tight lumbopelvic muscles, and strengthening weak and inhibited muscles. All of this should begin in the neutral spine position or a pelvic position, which minimizes acute discomfort.

The patient is asked to take on more challenging tasks while progressing through the program. Stabilization exercises are performed with the patient in a more dynamic, functional position and often include balance and proprioceptive activities. Strengthening of the core muscles surrounding the spine can be achieved in various ways. In the past several years, Pilates training has become very popular for this purpose. Finally, the patient should graduate to sport- or work-specific training designed to return the patient to his or her previous level of functioning.

Braces and belts

In patients who develop chronic injuries, an SIJ belt can provide compression and feedback to the gluteal muscles. Patients with ligamentous hypermobility can especially benefit from this apparatus because the belt can reduce SIJ rotation. The belt differs from a generalized lumbar orthosis because it is much thinner and thus secures across the anterior superior iliac spines.

Orthotics can decrease leg-length inequalities; these items include custom-fitted orthotics, internal shoe lifts, and external shoe lifts.

Medical Issues/Complications

SIJ dysfunction usually improves significantly, relatively quickly. Reexamine patients whose pain persists, despite treatment, for longer than 4 weeks and consider other diagnostic possibilities.

Other Treatment (Injection, manipulation, etc.)

Perform injection under fluoroscopic guidance (see image below). SIJ injection is frequently performed with a mixture of anesthetic and steroid, as described by Fortin in 1994 and others.[12] Post injection pain reduction offers significant diagnostic information when the actual source of the patient’s discomfort is unclear. Although a local blind injection into the area of maximal pain can be temporarily effective, the needle rarely enters the joint. CT scanning or MRI can also be used to guide injections into the SIJ, with excellent reliability.[33, 34, 35, 36]

Flouroscopically guided sacroiliac joint injection Flouroscopically guided sacroiliac joint injection. Contrast seen throughout the joint.

Unfortunately, injections usually offer only temporary relief. Therefore, couple injections with physical therapy and exercise to achieve more durable pain relief. The point in the course of treatment when a second or even third injection should be attempted is unclear. Most clinicians wait at least 2-4 weeks before proceeding with a repeat injection.

In a subset of patients who had temporary relief, Vallejo and coauthors performed pulsed radiofrequency denervation (PRFD) of lateral branches from L3-S2 and found good or excellent results in 16 of 22 subjects for 6-32 weeks.[41]

Manipulation has been reported in multiple studies as effective treatment for acute lower back pain. The SIJ is accessible to manipulation treatments, and these may be extremely effective. As with other passive modalities, these treatments should be coupled with an extensive active rehabilitative program. Manipulation following intra-articular injection has been reported anecdotally to be beneficial in selected cases.

 

Maintenance Phase

Rehabilitation Program

Physical therapy

After the patient's pain resolves and he or she has regained sufficient strength, therapy should be transitioned from the therapy office to the gym or home gym. The therapist should teach the patient a home gym or gym program, and the patient should perform stabilization and general training at least 3 times per week to prevent recurrence.

Return to Play

Similar to most conditions of mechanically related low back injury, an athlete's return to competition is a complex issue. In most SIJ injury cases, the athlete does not have a condition that can anatomically worsen with competition. However, pain may be exacerbated by the extreme motion and pelvic stress many athletes experience in their sport. Additionally, SIJ pain often leads to myofascial guarding and muscle imbalances, which, if not addressed before return to play, can lead to secondary injury in another part of the body. For example, a baseball pitcher with an SIJ strain may not be able to generate the support base or hip rotation needed to support the shoulder on overhead throws. Added stress to the shoulder can result in strains and even tears to the intrinsic elbow or shoulder muscles and ligaments.

Prevention

Prevention of lower back injuries, including those to the SIJ, is multifaceted and relies on patient education concerning the back. Excessive lifting with a rotatory component can injure the SIJ in a manner similar to lumbar disk injuries. Using accessory muscles in forceful activities and training them for these activities can prevent injury. Sport-specific training after rehabilitation and before return to play is most important to prevent future injury.

 

Medication

Medication Summary

As in most conditions involving acute and even chronic musculoskeletal pain, many oral medications can provide initial pain relief. NSAIDs are a mainstay and can be combined with acetaminophen for added effect. When the injury is acute and associated with secondary muscle spasm, muscle relaxants, light narcotics (eg, hydrocodone), or benzodiazepines are reasonable options. However, these medications should be administered cautiously and only for the initial acute phase of pain because dependence and tolerance can quickly occur.

Chronic SIJ dysfunction is more difficult to treat. Numerous medications are dispensed in a generic manner. Antidepressants, antiseizure agents, and antiarrhythmic agents are thought to be effective in neuropathic or nerve-related pain (radicular pain) and are not usually indicated for SIJ dysfunction pain.

Analgesics

Class Summary

For most episodes of SIJ pain, oral outpatient analgesics can achieve adequate pain control.

Acetaminophen (Tylenol, FeverAll)

DOC for pain in patients with documented hypersensitivity to aspirin or NSAIDs, with upper GI disease, or who are taking oral anticoagulants.

Nonsteroidal anti-inflammatory drugs (NSAIDs)

Class Summary

NSAIDs work by decreasing inflammatory reactions and providing direct pain relief. Numerous choices are available, and they are separated into different families of agents. If an NSAID is ineffective, another agent from a different family can often provide relief. Efficacy and adverse effect profiles differ among agents and families.

Cyclooxygenase (COX)–2 inhibitors had been shown to reduce certain adverse effects (eg, gastrointestinal [GI] bleeding) and provide similar efficacy to standard agents. Unfortunately, 2 of the 3 agents (ie, rofecoxib [Vioxx], valdecoxib [Bextra]) were voluntarily removed from the market by their parent companies when an increased potential risk of adverse cardiovascular events was identified in an increased number of patients taking the drugs. Dosing requirements are usually individualized, based on the individual patient and patient response.

Celecoxib (Celebrex)

DOC for patients with mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.

Ibuprofen (Motrin, Ibuprin)

DOC for patients with mild to moderate pain. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis.

Naproxen (Anaprox, Naprelan, Naprosyn)

Common NSAID family used for relief of mild to moderate pain.

Ketorolac (Toradol)

Used primarily for control of hyperacute severe pain. Potency is higher than other NSAIDs, and use results in more marked GI upset, platelet inhibition, and renal effects.

Muscle relaxants

Class Summary

Muscle relaxants can provide adjunctive pain relief in the acute setting. These agents usually should not be used in protracted courses.

Cyclobenzaprine hydrochloride (Flexeril)

Centrally acting relaxant of skeletal muscle. Usually gains most of its analgesic effect indirectly as a general relaxant and sedative. Structurally related to TCAs.

Metaxalone (Skelaxin)

Prescribed for use as a muscle relaxant. Mechanism of action not firmly established but may act as a CNS depressant and direct pain reliever. No direct action on the contractile mechanism of striated muscle. Can be used short term as an adjunct pain reliever in situations of severe myofascial strain.

 

Questions & Answers

Overview

What are sacroiliac joint (SIJ) injuries?

What is the prevalence of sacroiliac joint (SIJ) injuries?

What is the anatomy of the spine and pelvis relevant to sacroiliac joint (SIJ) injuries?

What are the biomechanics of sacroiliac joint (SIJ) injuries?

What is the role of innervation in sacroiliac joint (SIJ) injuries?

Presentation

How is pain characterized in sacroiliac joint (SIJ) injuries?

What is the role of pain provocation tests in the workup of sacroiliac joint (SIJ) injuries?

What is included in the physical exam to evaluate sacroiliac joint (SIJ) injuries?

What causes sacroiliac joint (SIJ) injuries?

DDX

What are the differential diagnoses for Sacroiliac Joint Injury?

Workup

What is the role of lab testing in the workup of sacroiliac joint (SIJ) injuries?

What is the role of imaging studies in the workup of sacroiliac joint (SIJ) injuries?

Treatment

What is the role of physical therapy (PT) in the treatment of acute sacroiliac joint (SIJ) injuries?

What is the role of osteopathic/chiropractic treatment in acute sacroiliac joint (SIJ) injuries?

How are worsening symptoms following physical therapy for acute sacroiliac joint (SIJ) injuries treated?

What is the role of medications in the treatment of acute sacroiliac joint (SIJ) injuries?

What is the role of surgery in the treatment of acute sacroiliac joint (SIJ) injuries?

Which specialist consultations are beneficial to patients with acute sacroiliac joint (SIJ) injuries?

How are acute sacroiliac joint (SIJ) injuries treated?

What is the role of physical therapy (PT) in the recovery phase of treatment for sacroiliac joint (SIJ) injuries?

What is the role of bracing in the recovery phase of treatment for sacroiliac joint (SIJ) injuries?

When should persistent pain be reevaluated during the treatment of sacroiliac joint (SIJ) injuries?

What is the role of injections in the recovery phase of treatment for sacroiliac joint (SIJ) injuries?

What is the role of physical therapy (PT) in the maintenance treatment of sacroiliac joint (SIJ) injuries?

Medications

Which medications are used in the treatment of sacroiliac joint (SIJ) injuries?

Which medications in the drug class Muscle relaxants are used in the treatment of Sacroiliac Joint Injury?

Which medications in the drug class Nonsteroidal anti-inflammatory drugs (NSAIDs) are used in the treatment of Sacroiliac Joint Injury?

Which medications in the drug class Analgesics are used in the treatment of Sacroiliac Joint Injury?