Paul Dreyfuss

The value of medical history and physical examination in diagnosing sacroiliac joint pain.

Study Design This prospective study evaluated the diagnostic utility of historically accepted sacroiliac joint tests. A multidisciplinary expert panel recommended 12 of the “best” sacroiliac joint tests to be evaluated against a criterion standard of unequivocal pain relief after an intra‐articular injection of local anesthetic into the sacroiliac joint. Objectives To identify a single sacroiliac joint test or ensemble of tests that are sufficiently useful in diagnosing sacroiliac joint disorders to be clinically valuable. Summary of Background Data No previous research has been done to evaluate any physical test of sacroiliac joint pain against an accepted criterion standard. Methods Historical data was obtained, and the 12 tests were performed by two examiners on 85 patients who subsequently underwent sacroiliac joint blocks. Ninety percent or more relief was considered a positive response, and less then 90% relief was considered a negative response. Results There were 45 positive and 40 negative responses. No historical feature, none of the 12 sacroiliac joint tests, and no ensemble of these 12 tests demonstrated worthwhile diagnostic value. Conclusion Sacroiliac joint pain is resistant to identification by the historical and physical examination data from tests evaluated in this study.

Efficacy and Validity of Radiofrequency Neurotomy for Chronic Lumbar Zygapophysial Joint Pain

STUDY DESIGN A prospective audit. OBJECTIVE To establish the efficacy of lumbar medial branch neurotomy under optimum conditions. SUMMARY OF BACKGROUND DATA Previous reports of the efficacy of lumbar medial branch neurotomy have been confounded by poor patient selection, inaccurate surgical technique, and inadequate assessment of outcome. METHODS Fifteen patients with chronic low back pain whose pain was relieved by controlled, diagnostic medial branch blocks of the lumbar zygapophysial joints, underwent lumbar medial branch neurotomy. Before surgery, all were evaluated by visual analog scale and a variety of validated measures of pain, disability, and treatment satisfaction. Electromyography of the multifidus muscle was performed before and after surgery to ensure accuracy of the neurotomy. All outcome measures were repeated at 6 weeks, and 3, 6, and 12 months after surgery. RESULTS Some 60% of the patients obtained at least 90% relief of pain at 12 months, and 87% obtained at least 60% relief. Relief was associated with denervation of the multifidus in those segments in which the medial branches had been coagulated. Prelesion electrical stimulation of the medial branch nerve with measurement of impedance was not associated with outcome. CONCLUSIONS Lumbar medial branch neurotomy is an effective means of reducing pain in patients carefully selected on the basis of controlled diagnostic blocks. Adequate coagulation of the target nerves can be achieved by carefully placing the electrode in correct position as judged radiologically. Electrical stimulation before lesioning is superfluous in assuring correct placement of the electrode.

Cervical transforaminal injection of corticosteroids into a radicular artery: a possible mechanism for spinal cord injury.

Spinal cord injury has been recognized as a complication of cervical transforaminal injections, but the mechanism of injury is uncertain. In the course of a transforaminal injection, an observation was made after the initial injection of contrast medium. The contrast medium filled a radicular artery that passed to the spinal cord. The procedure was summarily abandoned, and the patient suffered no ill effects. This case demonstrates that despite using careful and accurate technique, it is possible for material to be injected into a radicular artery. Consequently, inadvertent injection of corticosteroids into a radicular artery may be the mechanism for spinal cord injury following transforaminal injections. This observation warns operators to always perform a test injection of contrast medium, and carefully check for arterial filling using real-time fluoroscopy with digital subtraction.

Sacroiliac Joint Pain

Abstract The sacroiliac joint is a source of pain in the lower back and buttocks in approximately 15% of the population. Diagnosing sacroiliac joint‐mediated pain is difficult because the presenting complaints are similar to those of other causes of back pain. Patients with sacroiliac joint‐mediated pain rarely report pain above L5; most localize their pain to the area around the posterior superior iliac spine. Radiographic and laboratory tests primarily help exclude other sources of low back pain. Magnetic resonance imaging, computed tomography, and bone scans of the sacroiliac joint cannot reliably determine whether the joint is the source of the pain. Controlled analgesic injections of the sacroiliac joint are the most important tool in the diagnosis. Treatment modalities include medications, physical therapy, bracing, manual therapy, injections, radiofrequency denervation, and arthrodesis; however, no published prospective data compare the efficacy of these modalities.

Sensory stimulation-guided sacroiliac joint radiofrequency neurotomy: technique based on neuroanatomy of the dorsal sacral plexus.

Study Design. A retrospective audit and examination of anatomic findings. Objective. To examine the effectiveness of sensory stimulation-guided radiofrequency neurotomy for the treatment of recalcitrant sacroiliac joint pain. Summary of Background Data. Sacroiliac joint-mediated pain is a distinct clinical entity. The prevalence of intra-articular pain arising from the sacroiliac joint in patients with low back pain has been estimated at 15% to 30%. Unfortunately, the clinical success of current treatment methods for chronic sacroiliac pain is discouraging. Based on the anatomy of the sacral posterior primary rami and their lateral branch nerves, an anatomically based sensory stimulation-guided radiofrequency technique was developed to overcome the inherent challenge posed by the variable topography of the sacral lateral branch nerves. Materials and Methods. &NA; Anatomic Study. Meticulous dissection exposing the dorsal sacral plexus and lateral branch nerves entering the sacroiliac joint complex was performed on three cadaveric specimens. Small-gauge wires were placed adjacent to the lateral branch nerves entering the joint and over the dorsal sacrum to the dorsal sacral foramina. Fluoroscopic images were obtained correlating the location and number of these branches arising from the posterior primary rami of S1–S3 to identifiable bony landmarks. Clinical Study. A retrospective chart review was performed selecting patients who underwent sensory stimulation-guided sacral lateral branch radiofrequency neurotomy after dual analgesic sacroiliac joint deep interosseous ligament analgesic testing between February 17, 1998 and March 15, 1999. Results. A total of 14 patients met inclusion criteria for this retrospective study. Success was defined as greater than 60% consistent subjective relief and greater than a 50% consistent decrease in visual integer pain score, maintained for at least 6 months after the procedure. Sixty-four percent of patients experienced a successful outcome, with 36% experiencing complete relief. Fourteen percent of patients did not achieve any improvement. No patients experienced a complication or worsening of their pain from the procedure. Conclusions. A sensory stimulation-guided approach toward the identification and subsequent radiofrequencythermocoagulation of symptomatic sacral lateral branch nerves appears to offer significant therapeutic advantages over existing therapies for the treatment of chronic sacroiliac joint complex pain

The ability of lumbar medial branch blocks to anesthetize the zygapophysial joint. A physiologic challenge.

Study Design. Randomized, controlled, single‐blinded study. Objectives. To determine the physiologic effectiveness of lumbar medial branch blocks. Summary of Background Data. Zygapophysial joint pain can be diagnosed by anesthetization of the joint or its nerve supply (the medial branch divisions of the dorsal rami). The physiologic effectiveness of lumbar medial branch blocks has been assumed but not proven. Methods. Eighteen asymptomatic individuals were randomly assigned to either L4‐L5 or L5‐S1 zygapophysial joint injections with contrast medium until capsular distention elicited pain without extracapsular contrast spread. One week later, 15 blinded individuals underwent two randomized saline or 2% lidocaine medial branch injections that correlated to the innervation of the previously injected joint. Medial branch injections were performed such that inadvertent venous uptake was avoided in 14 individuals. Thirty minutes after medial branch injections, these 14 individuals underwent repeat capsular distention of the same zygapophysial joint provoked the prior week in an attempt to elicit another painful response. Results. All five control individuals who received saline medial branch i njections felt pain on repeat capsular distention. Nine individuals received 2% lidocaine medial branch blocks; eight felt no pain, and one felt pain on repeat capsular distention. Conclusions. There was a significant effect of 2% lidocaine (versus saline) medial branch injections on anesthetization of the zygapophysial joint when venous uptake was avoided during these injections. When properly performed, lumbar medial branch blocks successfully inhibit pain associated with capsular distention of the lumbar zygapophysial joints at a rate of 89%.

Positive sacroiliac screening tests in asymptomatic adults.

Study Design In a prospective, single-blinded study, the incidence of false-positive screening tests for sacroiliac joint dysfunction was investigated using the standing flexion, seated flexion, and Gillet tests in 101 asymptomatic subjects. Objectives This study determined if these commonly used sacroiliac screening tests can be abnormal in an asymptomatic population. Summary of Background Data The sacroiliac joint is a potential source of back and leg pain. One condition affecting this joint is termed sacroiliac joint dysfunction. Diagnosis of this is made primerily by physical examination using screening tests as preliminary diagnostic tools. These screening tests evaluate for asymmetry in sacroiliac motion due to a relative, unilateral hypomobility in one the sacroiliac joints. The specificity of these tests, however, has not been thoroughly evaluated in a well-selected asymptomatic population. Methods A single-blinded examiner performed the standing flexion, seated flexion, and Gillet tests on all subjects. An asymptomatic and a symptomatic group were studied. Results Overall, 20% of asymptomatic individuals had positive findings in one or more of these tests. The specific percentage of false positives are reported by test, age, sex, and side. Conclusion This study suggests that asymmetry in sacroiliac motion due to relative hypomobility as determined by these tests can occur in asymptomatic joints. Obviously, one should not rely solely on these tests to diagnose symptomatic sacroiliac dysfunction.

Atlanto-occipital and lateral atlanto-axial joint pain patterns.

Study Design Five asymptomatic subjects underwent provocative injections of the lateral atlanto-axial and atlanto-occipital joints. Objectives This study isolated and stimulated the lateral atlanto-axial and atlanto-occipital joints via fluoroscopically guided intra-articular injections to determine if they are potential pain generators. If they are pain generators, preliminary pain pattern maps will be constructed. Summary of Background Data The cervical zygapophyseal joints (C2–3 to C6–7) are potential pain generators as demonstrated by referred pain induced via isolated intra-articular joint injections in normal subjects. Tentative referral patterns based on direct mechanical stimulation of the lateral atlanto-axlal and atlanto-occlpital joints have not been reported. Methods Five volunteers without histories of upper cervical pain underwent two joint injections each. In all five subjects, the left atlanto-occipital and right lateral atlanto-axial joints were stimulated via injection of contrast medium causing distension of the joint capsule. Results Referred pain was produced with all ten injections. The lateral atlanto-axial injections resulted in consistent referral patterns, whereas the atlanto-occipital referral patterns varied significantly. A tentative composite diagram of the experimentally induced pain was created for each joint. Conclusion This study confirms the nociceptive ability of these cervical synovial joints. This study may assist the clinician in the differential diagnosis of head and neck pain.

Thoracic zygapophyseal joint pain patterns. A study in normal volunteers.

Study Design. Nine asymptomatic volunteers underwent 40 provocative intra-articular injections of the thoracic zygapophyseal joints. Objective. The purpose of the study was to isolate and stimulate the thoracic zygapophyseal joints via fluoroscopically gulded intra-articular injections to determine whether they are potential pain generators. Summary of Background Data. Experimentally, the cervical and lumbar zygapophyseal joints have been shown to produce pain, and tentative referral patterns have been established. Referral patterns based on stimulation of the thoracic zygapophyseal joints have not been previously reported. Methods. Four subjects underwent right-sided T3-T4, T5-T6, T7-T8, and T9-T10 joint injections, and four subjects underwent left-sided T4-T5, T6-T7, T8-T9, and T10-T11 joint injections. One subject underwent both the right - and left-sided joint injections. The zygapophyseal joints were injected with contrast medium only, and the quality, intensity, and distribution of evoked pain was recorded. Results. In this asymptomatic population, 72.5% of joints injected produced a sensation/pain that was different from the sensation of needle advancement through the soft tissues. In 27.5% of joints injected, there was no evoked pain despite adequate capsular distension. Evoked referral patterns were consistent in all subjects. Significant overlap occurred in the referral patterns, with most thoracic regions sharing 3–5 different joint referral zones. Conclusions. This study provides preliminary confirmation that the thoracic zygapophyseal joints can cause both local and referred pain. A referral pain diagram has been constructed.

Safeguards to Prevent Neurologic Complications after Epidural Steroid Injections: Consensus Opinions from a Multidisciplinary Working Group and National Organizations

Background: Epidural corticosteroid injections are a common treatment for radicular pain caused by intervertebral disc herniations, spinal stenosis, and other disorders. Although rare, catastrophic neurologic injuries, including stroke and spinal cord injury, have occurred with these injections. Methods: A collaboration was undertaken between the U.S. Food and Drug Administration Safe Use Initiative, an expert multidisciplinary working group, and 13 specialty stakeholder societies. The goal of this collaboration was to review the existing evidence regarding neurologic complications associated with epidural corticosteroid injections and produce consensus procedural clinical considerations aimed at enhancing the safety of these injections. U.S. Food and Drug Administration Safe Use Initiative representatives helped convene and facilitate meetings without actively participating in the deliberations or decision-making process. Results: Seventeen clinical considerations aimed at improving safety were produced by the stakeholder societies. Specific clinical considerations for performing transforaminal and interlaminar injections, including the use of nonparticulate steroid, anatomic considerations, and use of radiographic guidance are given along with the existing scientific evidence for each clinical consideration. Conclusion: Adherence to specific recommended practices when performing epidural corticosteroid injections should lead to a reduction in the incidence of neurologic injuries.