Ligaments stabilizing the sacrum and sacroiliac joint: a comprehensive review

The sacroiliac joint is a diarthrodial synovial joint in the pelvis. Anatomically, it is described as a symphysis, its synovial joint characteristics being limited to the distal cartilaginous portion on the iliac side. It is a continuous ligamentous stocking comprising interconnecting ligamentous structures and surrounding fascia. Its ligaments, the primary source of its stability, include the anterior, interosseous and dorsal sacroiliac, the iliolumbar, sacrotuberous, and sacrospinous. Structural reinforcement is also provided by neighboring fascia and muscles. Lower back pain is a common presentation of sacroiliac joint disease, the best-established treatments being corticosteroid injections, bipolar radiofrequency ablation, and sacroiliac joint fusion.

     

Viscosupplementation: A new concept in the treatment of sacroiliac joint syndrome: A preliminary report of four cases

Background and Objectives. We describe a new therapeutic modality for sacroiliac joint syndrome that represents an alternative to other treatment modalities. We report on four cases of sacroiliac joint syndrome with severe pain. Methods: Three patients had undergone operative treatment of the lumbar spine and one patient suffered from severe osteoarthritis of the spine. All patients were diagnosed with sacroiliac joint syndrome by means of patient history, physical examination, and intra-articular local anesthetic injection preceded by sacroiliac arthrogram. All patients received three injections of Hylan GF 20 in the sacroiliac joints 2 weeks apart. Results: Twelve to 16 weeks after the injections, the pain was reported to be 40–67% better when measured on the visual analog scale. The duration of the beneficial effect of Hylan on arthralgia and joint function was undetermined. Conclusions. Viscosupplementation of the sacroiliac joint induced a significant degree of analgesia in all four patients. This treatment modality could represent an option in the management of sacroiliac joint pain and dysfunction.     

Concomitant sacroiliac joint pain in patients with lumbar disc herniation: case series

Recent studies have shown that not all lumbar disc herniations are symptomatic and that when followed longitudinally, these patients develop back pain independent of the previous imaging study. This is a case report of two patients with radicular symptoms and lumbar disc herniations that underwent diagnostic injections to locate their pain generator. Both patients failed to respond to transforaminal epidural steroid injections. Transforaminal injections can be diagnostically sensitive for radicular pain but not specific. This is a direct result of the spread of medication to other levels in the epidural space, thus affecting multiple levels of innervation. Follow-up with two sacroiliac injections gave significant relief of their pain. They were both treated conservatively for sacroiliac joint pain and did well. One remained pain free after several months and the second remained with minimal pain until she presented again in her 3rd month of pregnancy with return of her pain. The differential diagnosis of lumbar radicular pain is discussed as well as the authors' experience in using diagnostic injections.     

An electrophysiologic study of mechanoreceptors in the sacroiliac joint and adjacent tissues

STUDY DESIGN: The somatosensory afferent units in the sacroiliac joint of an animal model were investigated using an electrophysiologic technique. OBJECTIVES: To identify the mechanosensitive receptive fields in the sacroiliac joint, and to determine their distribution and characteristics. SUMMARY OF BACKGROUND DATA: The sacroiliac joint is considered to be a source of lower back pain. Although there have been clinical studies on the diagnosis of sacroiliac joint pain, no satisfactory diagnostic method other than joint blocks has been reported. It still is not clear whether the sacroiliac joints actually transmit pain to the central nervous system. The sensory innervation of the sacroiliac joint has not been fully characterized neurophysiologically. METHODS: Experiments were performed on 10 adult cats weighing 2.6 to 4 kg. The animals were anesthetized with intravenous sodium pentobarbital. An L4-L7 laminectomy was performed. The L4-L6 dorsal roots were cut at their proximal ends, split, and draped over a bipolar recording electrode. Glass probes were used to search the sacroiliac joint and adjacent tissues for mechanosensitive units. When units were identified, they were stimulated electrically to obtain conduction velocities and by Semmes-Weinstein monofilaments to determine mechanical thresholds. RESULTS: In the sacroiliac joint and adjacent muscles, 29 discrete mechanosensitive units were identified. Of these 29 units, 26 were found in the posterior sacroiliac ligament and the remaining 3 in the adjacent muscles. Also, 16 units (55%) were identified in the proximal third of the sacroiliac joint. Conduction velocities of the units ranged from 3.1 to 22 m/second (average, 9.2 m/second), and 26 units were group III. Mechanical thresholds of the units ranged from 4.6 to 164.3 g (average, 69.7 g). Whereas 28 units (96.6%) had thresholds higher than 7 g, one unit (3.4%) had a threshold lower than 7 g. CONCLUSIONS: Group III units with mechanical thresholds higher than 7 g may serve as nociceptors, and units with thresholds of lower than 7 g may serve as proprioceptors. The current study showed that most of the units in the sacroiliac joint were high-threshold group III units that perhaps had a nociceptive function. This result suggests that the sacroiliac joint may be a source of lower back pain in humans. This study also showed that the sacroiliac joint has little proprioceptive function.     

A critical review of the evidence for the use of zygapophysial injections and radiofrequency denervation in the treatment of low back pain.

BACKGROUND CONTEXT: Lumbar zygapophysial joints are currently believed to be a cause of axial low back pain. Once this diagnosis is made, decisions about when to institute a particular intervention and which treatment to offer is regionally and specialty dependent. PURPOSE: To perform a critical review of prior published studies assessing the use of interventional treatment options for the treatment of lumbar zygapophysial joint syndrome. STUDY DESIGN: Evidence-based medicine analysis of current literature. METHODS: A database search of Medline (PubMed, Ovid and MDConsult), Embase and the Cochrane database was conducted. The keywords used were low back pain, lumbar zygapophysial joint, lumbar facet joint, radiofrequency denervation, medial branch block, and intraarticular injection. After identifying all relevant literature, each article was reviewed. Data from the following categories were compiled: inclusion criteria, randomization of subjects, total number of subjects involved at enrollment and at final analysis. statistical analysis used, intervention performed, outcome measures, follow-up intervals and results. Guidelines described by the Agency for Health Care Policy and Research were then applied to these data. RESULTS: This review determined that the evidence for the treatment of lumbar zygapophysial joint syndrome with intraarticular injections should be rated as level III (moderate) to IV (limited) evidence, whereas that for radiofrequency denervation is at a level III. CONCLUSIONS: Current studies fail to give more than sparse evidence to support the use of interventional techniques in the treatment of lumbar zygapophysial joint-mediated low back pain. This review emphasizes the need for larger, prospective, randomized controlled trials with uniform inclusion and exclusion criteria, standardized treatment, uniform outcome measures and an adequate duration of follow-up period so that definitive recommendations for the treatment of lumbar zygapophysial joint-mediated pain can be made.     

The role of sacroiliac joint dysfunction in the genesis of low back pain: the obvious is not always right

Background context It is a common practice to the link low back pain with protruding disc even when neurological signs are absent. Because pain caused by sacroiliac joint dysfunction can mimic discogenic or radicular low back pain, we assumed that the diagnosis of sacroiliac joint dysfunction is frequently overlooked. Purpose To assess the incidence of sacroiliac joint dysfunction in patients with low back pain and positive disc findings on CT scan or MRI, but without claudication or objective neurological deficits. Methods Fifty patients with low back pain and disc herniation, without claudication or neurological abnormalities such as decreased motor strength, sensory alterations or sphincter incontinence and with positive pain provocation tests for sacroiliac joint dysfunction were submitted to fluoroscopic diagnostic sacroiliac joint infiltration. Results The mean baseline VAS pain score was 7.8 ± 1.77 (range 5–10). Thirty minutes after infiltration, the mean VAS score was 1.3 ± 1.76 (median 0.000E+00 with an average deviation from median = 1.30) (P = 0.0002). Forty-six patients had a VAS score ranging from 0 to 3, 8 weeks after the fluoroscopic guided infiltration. There were no serious complications after treatment. An unanticipated motor block that required hospitalization was seen in four patients, lasting from 12 to 36 h. Conclusions Sacroiliac joint dysfunction should be considered strongly in the differential diagnosis of low back pain in this group of patients.     

Sensory innervation of the sacroiliac joint in rats

STUDY DESIGN: The segmental levels of dorsal root ganglions innervating the sacroiliac joint in rats were investigated using the retrograde transport method. The pathways and functions of the nerve fibers supplying the sacroiliac joint were determined by immunohistochemical detection of transported tracer. OBJECTIVES: To study the sensory innervation of the sacroiliac joint and to elucidate the neural pathways of low back pain originating from the sacroiliac joint. SUMMARY OF BACKGROUND DATA: The sacroiliac joint is a possible source of low back pain. The L4-S4 spinal nerves have been regarded as the nerves innervating the sacroiliac joint in humans. However, the origins of nerve fibers have not been analyzed experimentally with tracer methods. METHODS: Cholera toxin B subunit, a neural tracer, was injected into the left sacroiliac joint of adult rats, and the bilateral dorsal root ganglions were immunohistochemically examined 4 days after injection. In another rat group, the dorsal root ganglions were examined using the same methods after resection of the left sympathetic trunk from L2 to the most caudal level. Thus, the pathways of the nerve fibers supplying the sacroiliac joint were investigated. RESULTS: Labeled neurons were mainly located in the ipsilateral dorsal root ganglions from L1 to S2 of the unsympathectomized rats and in the ipsilateral dorsal root ganglions from L4 to S2 of the sympathectomized rats. CONCLUSIONS: The sacroiliac joint was innervated by sensory neurons in dorsal root ganglions ipsilateral to the joint from L1 to S2. Sensory fibers from the L1 and L2 dorsal root ganglions passed through the paravertebral sympathetic trunk.     

Recognizing specific characteristics of nonspecific low back pain

A retrospective review of 1293 cases of low back pain treated over a 12-year period revealed that sacroiliac joint syndrome and posterior joint syndromes were the most common referred-pain syndromes, whereas herniated nucleus pulposus and lateral spinal stenosis were the most common nerve root compression lesions. Referred pain syndromes occur nearly twice as often and frequently mimic the clinical presentation of nerve root compression syndromes. Combined lesions occurred in 33.5% of cases. Lateral spinal stenosis and herniated nucleus pulposus coexisted in 17.7%. In 30% of the cases of spondylolisthesis, the radiographic findings were incidental and the source of pain was the sacroiliac joint. Distinguishing radicular from referred pain, recognition of coexisting lesions, and correlation of diagnostic imaging with the overall clinical presentation facilities formulation of a rational plan of therapy. The above-outlined approach to managing low back pain evolved over a 12-year period. Designed to establish a specific diagnosis, it should yield excellent or good results in 84% of patients.     

Sacroiliac joint pain after lumbar fusion. A study with anesthetic blocks

Low back pain persisting or appearing after a technically successful lumbar fusion challenges clinicians. In this context, the sacroiliac joint could be a possible source of pain, but the frequency of its responsibility is not really known. We used sacroiliac anesthetic blocks, the gold standard for diagnosis, to determine this frequency. Our second goal was to search predictive factors for a positive block. Our prospective series consisted of 40 patients with persistent low back pain after a technically successful fusion who received a sacroiliac anesthetic block under fluoroscopic control. The diagnostic criterion was a relief of more than 75% of the pain on a visual analog scale. We found a 35% rate of positive blocks. The only criterion that characterized these patients was a postoperative pain different from the preoperative pain in its distribution ( p =0.017). A free interval of more than 3 months between surgery and appearance of the pain had an indicative value ( p =0.17). An increased uptake in the sacroiliac on bone scintigraphy or a past history of posterior iliac bone-graft harvesting had no significant value ( p =0.74 and p =1.0, respectively). The sacroiliac joint is a possible source of pain after lumbar fusion. The anesthetic block under fluoroscopic control remains the gold standard.     

Absence de fiabilité des tests cliniques et des blocs pour le diagnostic positif de l’origine sacro-iliaque d’une douleur

Mapping studies of pain elicited by injections into the sacroiliac joints (SIJs) suggest that sacroiliac joint syndrome (SIJS) may manifest as low back pain, sciatica, or trochanteric pain. Neither patient-reported symptoms nor provocative SIJ maneuvers are sensitive or specific for SIJS when SIJ block is used as the diagnostic gold standard. This has led to increasing diagnostic use of SIJ block, a procedure in which an anesthetic is injected into the joint under arthrographic guidance. However, several arguments cast doubt on the validity of SIJ block as a diagnostic gold standard. Thus, the effects of two consecutive blocks are identical in only 60% of cases, and the anesthetic diffuses out of the joint in 61% of cases, often coming into contact with the sheaths of the adjacent nerve trunks or roots, including the lumbosacral trunk (which may contribute to pain in the groin or thigh) and the L5 and S1 nerve roots. These data partly explain the limited specificity of SIJ block for the diagnosis of SIJS and the discordance between the pain elicited by the arthrography injection and the response to the block. The limitations of provocative maneuvers and SIJ blocks may stem in part from a contribution of extraarticular ligaments to the genesis of pain believed to originate within the SIJs. These ligaments include the expansion of the iliolumbar ligaments, the dorsal and ventral sacroiliac ligaments, the sacrospinous ligaments, and the sacrotuberous ligaments (sacroiliac joint lato-sensu). They play a role in locking or in allowing motion of the SIJs. Glucocorticoids may diffuse better than anesthetics within these ligaments. Furthermore, joint fusion may result in ligament unloading.     

Provocative sacroiliac joint maneuvers and sacroiliac joint block are unreliable for diagnosing sacroiliac joint pain

Mapping studies of pain elicited by injections into the sacroiliac joints (SIJs) suggest that sacroiliac joint syndrome (SIJS) may manifest as low back pain, sciatica, or trochanteric pain. Neither patient-reported symptoms nor provocative SIJ maneuvers are sensitive or specific for SIJS when SIJ block is used as the diagnostic gold standard. This has led to increasing diagnostic use of SIJ block, a procedure in which an anesthetic is injected into the joint under arthrographic guidance. However, several arguments cast doubt on the validity of SIJ block as a diagnostic gold standard. Thus, the effects of two consecutive blocks are identical in only 60% of cases, and the anesthetic diffuses out of the joint in 61% of cases, often coming into contact with the sheaths of the adjacent nerve trunks or roots, including the lumbosacral trunk (which may contribute to pain in the groin or thigh) and the L5 and S1 nerve roots. These data partly explain the limited specificity of SIJ block for the diagnosis of SIJS and the discordance between the pain elicited by the arthrography injection and the response to the block. The limitations of provocative maneuvers and SIJ blocks may stem in part from a contribution of extraarticular ligaments to the genesis of pain believed to originate within the SIJs. These ligaments include the expansion of the iliolumbar ligaments, the dorsal and ventral sacroiliac ligaments, the sacrospinous ligaments, and the sacrotuberous ligaments (sacroiliac joint lato-sensu). They play a role in locking or in allowing motion of the SIJs. Glucocorticoids may diffuse better than anesthetics within these ligaments. Furthermore, joint fusion may result in ligament unloading.     

Computed tomography findings in patients with sacroiliac pain

This retrospective study evaluated the diagnostic value of computed tomography in patients with sacroiliac pain. Computed tomography scans of the sacroiliac joints of 62 patients with sacroiliac joint pain were reviewed. The criteria to include the patient in the current study were pain relief after a local injection in the sacroiliac joint under computed tomography guidance, a physical examination consistent with a sacroiliac origin of the pain, and negative magnetic resonance imaging of the lumbar spine. A control group consisted of 50 patients of matched age who had computed tomography scans of the pelvis for a reason other than pelvic or back pain. Computed tomography scans showed one or more findings in 57.5% and 31% of the sacroiliac joints in the symptomatic and the control groups, respectively. The computed tomography scans were negative in 37 (42.5%) symptomatic sacroiliac joints with a positive sacroiliac joint injection test. The sensitivity of computed tomography was 57.5 % and its specificity was 69%. The finding of the current study suggests limited diagnostic value of computed tomography in sacroiliac joint disease because of its low sensitivity and specificity. With clinical suspicion of a sacroiliac origin of pain, intraarticular injection is currently the only means to confirm that diagnosis.     

Value of quantitative radionuclide bone scanning in the diagnosis of sacroiliac joint syndrome in 32 patients with low back pain

A prospective study was performed to compare the results of quantitative radionuclide bone scanning with those of sacroiliac joint anesthetic block in patients with unilateral low back pain. Thirty-four subjects, forming the control group, underwent quantitative radionuclide bone scanning of the sacroiliac joints. The normal values in sacroiliac uptake difference were taken to be between –1.7% and +6.2%. Thirty-two patients with chronic unilateral low back pain underwent sacroiliac bone scanning and sacroiliac joint block. Six of the seven patients with increased uptake > 6.2% on the painful side had at least 75% pain reduction in response to the block. The sensitivity, specificity, and positive and negative predictive values of the quantitative bone scanning in the unilateral mechanical sacroiliac joint syndrome were 46.1%, 89.5%, 85.7%, and 72%, respectively. Received: 21 July 1997 Revised: 17 November 1997 Accepted: 22 January 1998     

Lumbar spine pain originating from vertebral osteophytes.

BACKGROUND AND OBJECTIVES: Axial spine pain originates from a number of structures. Putative pain generators include facet joints, intervertebral disks, sacroiliac joints, and myofascial structures. Osteophytes originating from lumbar vertebral bodies in the area of the intervertebral disks may be a source of nociceptive low back pain which may respond to local injection. METHODS: Five patients with axial low back pain unresponsive to traditional treatment modalities were treated with fluoroscopic guided injection of local anesthetic and corticosteroid near large intervertebral osteophytes. RESULTS: All 5 patients experienced relief. CONCLUSION: Vertebral osteophytes may be a source of axial spine pain. Injection of painful osteophytes with a local anesthetic and corticosteroid solution may produce pain relief.     

Functional and radiographic outcome of sacroiliac arthrodesis for the disorders of the sacroiliac joint.

BACKGROUND CONTEXT: The sacroiliac joint is known to be a possible cause of chronic low back pain, but the diagnosis and treatment of disorders of the sacroiliac joint have been difficult and controversial. PURPOSE: To describe the outcome of sacroiliac joint arthrodesis for sacroiliac joint disorders, with the hypothesis that sacroiliac arthrodesis leads to improved postoperative function. STUDY DESIGN/SETTING: Consecutive case series performed in an academic medical institution. PATIENT SAMPLE: The patient population consisted of 20 patients undergoing sacroiliac joint arthrodesis between December 1994 and December 2001. Patients undergoing concomitant procedures at the time of sacroiliac joint arthrodesis were excluded. The 3 men and 17 women in the study group had an average age of 45.1 years (range 21.8-66.4 years), a mean duration of symptoms of 2.6 years (range 0.5-8.0 years), and a mean follow-up period of 5.8 years (range 2.0-9.0 years). OUTCOME MEASURES: Outcome measures included general health and function, clinical evaluation, and radiographic assessment. METHODS: For all 20 patients, nonoperative treatment had failed, and for all, the diagnosis was confirmed by pain relief with intraarticular sacroiliac joint injections under fluoroscopic guidance. Sacroiliac joint arthrodesis (via a modified Smith-Petersen technique) was recommended only when a positive response to the injection was noted, and patients had recurrence of symptoms after the initial positive response. Preoperative and postoperative general health and function were assessed via the 36-item Short-Form (SF-36) Health Survey and American Academy of Orthopaedic Surgeons (AAOS) Modems Instrument, which were collected prospectively. Medical records and plain radiographs were reviewed retrospectively to determine the clinical and radiographic outcome. RESULTS: Multiple etiologies of sacroiliac symptoms were observed: sacroiliac joint dysfunction (13 patients), osteoarthritis (5 patients), and spondyloarthropathy and sacroiliac joint instability (1 each). Seventeen patients (85%) had solid fusion. Fifteen patients (75%) completed preoperative and postoperative SF-36 forms. Significant (p< or =.05) improvement occurred in the following categories: physical functioning, role physical, bodily pain, vitality, social functioning, role emotional, and neurogenic and pain indices. Improvement (not statistically significant) was also noted in general and mental health. CONCLUSIONS: For carefully selected patients, sacroiliac arthrodesis appears to be a safe, well-tolerated, and successful procedure, leading to significant improvement in functional outcome and a high fusion rate. To the authors' knowledge, the current report is the largest series to document the functional and radiographic outcome of sacroiliac joint arthrodesis.     

Randomized Placebo-controlled Study Evaluating Lateral Branch Radiofrequency Denervation for Sacroiliac Joint Pain

Background: Sacroiliac joint pain is a challenging condition accounting for approximately 20% of cases of chronic low back pain. Currently, there are no effective long-term treatment options for sacroiliac joint pain.

Methods: A randomized placebo-controlled study was conducted in 28 patients with injection-diagnosed sacroiliac joint pain. Fourteen patients received L4-L5 primary dorsal rami and S1-S3 lateral branch radiofrequency denervation using cooling-probe technology after a local anesthetic block, and 14 patients received the local anesthetic block followed by placebo denervation. Patients who did not respond to placebo injections crossed over and were treated with radiofrequency denervation using conventional technology.

Results: One, 3, and 6 months after the procedure, 11 (79%), 9 (64%), and 8 (57%) radiofrequency-treated patients experienced pain relief of 50% or greater and significant functional improvement. In contrast, only 2 patients (14%) in the placebo group experienced significant improvement at their 1-month follow-up, and none experienced benefit 3 months after the procedure. In the crossover group (n = 11), 7 (64%), 6 (55%), and 4 (36%) experienced improvement 1, 3, and 6 months after the procedure. One year after treatment, only 2 patients (14%) in the treatment group continued to demonstrate persistent pain relief.     

超声引导下骶髂关节腔内注射治疗骶髂关节炎

目的研究超声引导下骶髂关节腔内注射治疗骶髂关节炎的可能性和有效性。方法研究了34位骶髂关节炎病人。在超声引导下有60个骶髂关节接受注射。关节内注射皮质类固醇激素和局部麻醉药。摄取即时影像以评价超声引导技术的精确性。结果60例中，46例(76．7％)成功，14例(23．3％)错误。前30个关节成功率60％，以后技术逐步提高，后30个关节成功率93．5％。平均操作时间9min。结论我们的初步经验表明，超声引导下骶髂关节腔内注射治疗骶髂关节炎，可以代替其他的影像引导方式。对于有经验的影像医师，这项技术是安全、迅速、可重复的。     

Lumbar discogenic pain

Lumbar discogenic pain in the sense of an internal disc disruption (IDD) represents a nociceptive pain syndrome with the source of pain in the innervated outer third of the annulus. Such discs anatomically appear with almost normal contours. Neither clinical nor technical assessments have any diagnostic value, with the exception of MRI which has been shown, if present in symptomatic patients, to have a positive predictive value of up to 89 % to indicate a strong correlation to a painful grade 3 or 4 fissure. However, only the stimulation of a disc (controlled provocation discography) with a subsequent CT scan is of exclusive diagnostic value. As an underlying pathomechanism, a compression fracture of the superior subchondral endplate like a fatigue fracture is discussed. In this way, a deterioration of the homogeneous intradiscal stress distribution could occur with consecutive damage to the internal disc environment and the expression of a radial fissure. The clinical picture of discogenic pain is non-specific. It does not correlate with degenerative changes. It does not differ from any other back pain. Thus, it has to be differentiated from zygapophysial joint pain as well as from sacroiliac joint pain and muscular-ligamentous pain sources. In a single study of American workers, the prevalence of IDD was 39 %, rendering it one of the most important causes for patients with a specified source of back pain.     

Pathogenesis, diagnosis, and treatment of lumbar zygapophysial (facet) joint pain

Lumbar zygapophysial joint arthropathy is a challenging condition affecting up to 15% of patients with chronic low back pain. The onset of lumbar facet joint pain is usually insidious, with predisposing factors including spondylolisthesis, degenerative disc pathology, and old age. Despite previous reports of a "facet syndrome," the existing literature does not support the use of historic or physical examination findings to diagnose lumbar zygapophysial joint pain. The most accepted method for diagnosing pain arising from the lumbar facet joints is with low-volume intraarticular or medial branch blocks, both of which are associated with high false-positive rates. Standard treatment modalities for lumbar zygapophysial joint pain include intraarticular steroid injections and radiofrequency denervation of the medial branches innervating the joints, but the evidence supporting both of these is conflicting. In this article, the authors provide a comprehensive review of the anatomy, biomechanics, and function of the lumbar zygapophysial joints, along with a systematic analysis of the diagnosis and treatment of facet joint pain.