Guidelines for the use of discography for the diagnosis of painful degenerative lumbar disc disease

Operative and nonoperative treatment approaches for lumbar degenerative disc disease have similar long-term clinical outcomes among patients with positive discography

OBJECTIVE

It remains unclear whether fusion for lumbar degenerative disc disease with positive discography produces better outcomes compared with nonoperative treatment. The aim of this study was to compare outcomes of patients with discography-concordant lumbar degenerative disc disease electing for fusion versus nonoperative treatment.

METHODS

We retrospectively reviewed consecutive patients with back pain and concordant lumbar discogram who were offered fusion. Follow-up questionnaires included pain score, Oswestry disability index, short form-12, and satisfaction scale. Patients were stratified based on whether they elected for fusion or nonoperative treatment.

RESULTS

Overall follow-up was 48% (96/200). Patients lacking follow-up were slightly older (P = 0.021) and less likely to be smokers (P = 0.013). Between patients with and without follow-up, there were no significant differences in pain score at initial visit, body mass index, or gender (P ≥ 0.40). The 96 patients for whom follow-up was obtained included 53 in the operative and 43 in the nonoperative groups. At baseline, there were no significant differences between these groups based on age, pain score, body mass index, smoking, or gender (P ≥ 0.25). Mean follow-up was 63 months for operative and 58 months for nonoperative patients (P = 0.20). The mean pain score at last follow-up improved significantly for operative and nonoperative patients (P < 0.001). At follow-up, operative and nonoperative groups did not differ significantly with regard to pain scores, Oswestry disability index, short form-12, or satisfaction scale.

CONCLUSIONS

Comparison of long-term outcomes for patients with back pain and concordant discography did not demonstrate a significant difference in outcome measures of pain, health status, satisfaction, or disability based on whether the patient elected for fusion or nonoperative treatment.

The LP-ESP(®) lumbar disc prosthesis with 6 degrees of freedom: development and 7 years of clinical experience

The viscoelastic lumbar disk prosthesis-elastic spine pad (LP-ESP(®)) is an innovative one-piece deformable but cohesive interbody spacer providing 6 full degrees of freedom about the 3 axes, including shock absorption. A 20-year research program has demonstrated that this concept provides mechanical properties very close to those of a natural disk. Improvements in technology have made it possible to solve the problem of the bond between the elastic component and the titanium endplates and to obtain an excellent biostability. The prosthesis geometry allows limited rotation and translation with resistance to motion (elastic return property) aimed at avoiding overload of the posterior facets. The rotation center can vary freely during motion. It thus differs substantially from current prostheses, which are 2- or 3-piece devices involving 1 or 2 bearing surfaces and providing 3 or 5 degrees of freedom. This design and the adhesion-molding technology differentiate the LP-ESP prosthesis from other mono-elastomeric prostheses, for which the constraints of shearing during rotations or movement are absorbed at the endplate interface. Seven years after the first implantation, we can document in a solid and detailed fashion the course of clinical outcomes and the radiological postural and kinematic behavior of this prosthesis.

Provocative lumbar discography versus functional anesthetic discography: a comparison of the results of two different diagnostic techniques in 52 patients with chronic low back pain

BACKGROUND CONTEXT

There is mounting evidence that the currently available techniques for the diagnosis of discogenic low back pain are insufficiently accurate-this may explain some of the variability in outcomes of surgery for this important clinical problem. New diagnostic methods are needed to address this diagnostic issue; improvements here may do as much to improve overall patient outcomes as improvements in surgical treatment methods.

PURPOSE

To compare the results of standard pressure-controlled provocative discography (PD) to those of the functional anesthetic discogram (FAD) in a series of patients presenting with chronic low back pain and considering surgical treatment.

STUDY DESIGN

Prospective clinical series in an academic spinal surgical practice.

PATIENT SAMPLE

Fifty-two patients presenting with chronic low back pain; mean age 45 years (range, 24-70 years); 28 women, 24 men; and 25% in workman's compensation program.

OUTCOME MEASURES

Oswestry, visual analog scale for back pain, distress and risk assessment method psychometric analysis, demographic data, magnetic resonance imaging scan of lumbar spine. During provocative discogram: pressurization at pain, pain level, and concordancy. During FAD: position or activity used to elicit typical pain, baseline pain level before injection, during injection, at 5, 10, and 20 minutes after the injection, and substance injected.

METHODS

Standard pressure-controlled PD was performed, followed by (in positive cases or in patients with clinical features and imaging studies felt to be highly suggestive of symptomatic disc degeneration) the FAD test-an assessment of the response to injection of a low dose of local anesthetic into the disc during a position productive of the patient's typical pain.

RESULTS

Discordant results of the two tests were noted in 46% of the patients in the series. Of them, 26% of patients with positive PD had negative findings on the FAD test; 16% had positive findings at a single level only, whereas the provocative discogram had been positive at two or more levels; 4% had new positive findings on the FAD test.

CONCLUSIONS

We have presented the results of a new diagnostic technique in 52 patients with chronic low back pain presumed discogenic in origin that was designed to help differentiate between symptomatic and asymptomatic disc degeneration. The findings of the test differed from those of standard pressure-controlled PD in 46% of the cases reported on here. Further studies are needed to demonstrate the clinical utility of the test.

Discography: can pain in a morphologically normal disc be due to an adjacent abnormal disc?

Symptomatic patients who had Magnetic Resonance Imaging findings of degenerative disc disease and who failed conservative treatment were identified. As a preoperative test, these patients underwent discography. The patients, who experienced pain with injection into a morphologically normal disc adjacent to a morphologically abnormal disc, were included in the study. These patients subsequently had repeat discograms, during which the adjacent abnormal disc was first anesthetized with 2% lidocaine and the discogram was repeated at the adjacent normal level. All patients were blinded as to the nature of the procedure. Nine patients were identified (7 males and 2 females). The average age was 46.5 years (32-68). Two patients had a previous L4-Sacrum anterior and posterior fusion while 2 patients had L5-Sacrum anterior and posterior fusions. These four patients had solid fusions on Computerized Tomography scan and had developed adjacent segment degeneration according to MRI. Overall, each patient underwent an average of four discograms, at the lowest mobile disc segments. All of the patients were found to have a painful but morphologically normal disc adjacent to a painful and morphologically abnormal disc. The morphologically abnormal disc was anesthetized and the discography repeated on the normal disc. Upon this repeat discography, none of the patients experience any pain. The authors recommend anesthetizing painful abnormal discs prior to discography of the adjacent discs. This technique may avoid unnecessary dismissal of patients from treatment because of an appropriate response to discography. The normal disc may be due to referred pain from an adjacent abnormal disc.

Diagnostic relevance of pressure-controlled discography

Discogenic pain is a leading cause of chronic low back pain. The authors investigated the efficacy of pressure-controlled discography to determine its role in clinical decision-making for the management of patients with discogenic pain. Pressure-controlled discography was performed in 21 patients (51 discs) with pain-provocation, followed by post-discography computerized tomography scans. Pain response was classified as positive response and negative response, and measured with visual analog scale scores. Discographic findings were graded by the modified Dallas discogram scale. Elastance, pain provocation on intradiscal pressure, pressure and volume of initial pain response, and pain response intensity were statistically analyzed. Elastance showed significant differences between Grade 0 and Grade 4 and 5. Decreased elastance with positive pain response group was a good indicator to imply that disc degeneration presumably is a pain generator. Results of pain response were well correlated with intradiscal pressure but not with the amount of injected volume. Among 31 discs of Grade 4 and 5, 74% showed negative pain response and 26% showed positive response. It was concluded that pressure-controlled discography was useful to diagnose discogenic pain and excellent guide in decision-making for spinal operations.

The Relation Between Annular Disruption on Computed Tomography Scan and Pressure-Controlled Diskography

OBJECTIVE

To analyze the relation between annular disruption determined by computed tomography (CT) scan and diskographic findings using pressure-controlled manometric diskography.

DESIGN

Cross-sectional using prospectively gathered data.

SETTING

Ambulatory spine intervention unit.

SPECIMENS

Two hundred seventy-nine disks from 86 patients (55 men, 31 women) who were referred for diskography of suspected chronic diskogenic low back pain.

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

The grade of annular disruption was rated using CT diskography and fluoroscopic imaging as follows: 0 (no disruption); 1 (extension into the inner third of the annulus); 2 (extension into the middle third of the annulus); 3 (extension into the outer third of the annulus); 4 (circumferential extension with a >30 degrees arc at the disk center); and 5 (contrast media leakage into the outer space). Diskography was performed via a pressure-controlled manometric technique using an injection rate of .05 mL/s and a restricted total volume of 3.5 mL. Pain was rated on a 0 to 10 numeric rating scale (NRS). Criteria for symptomatic disks included provocation of patient concordant pain (NRS score, > or =6/10) at 50psi or less above opening pressure, with 3.5 mL or less of total volume. Symptomatic disks were classified as "low pressure sensitive" or "high pressure sensitive" based on the pressure level that evoked pain. Disks classified as low pressure sensitive required an NRS score of 6 out of 10 or higher at 15 psi or less above opening pressure. Disks classified as high pressure sensitive required an NRS score of 6 out of 10 or higher at pressures within a range of 15 to 50 psi.

RESULTS

The numbers of disks at each annular disruption grade were 19 (6.8%) at grade 0, 29 (10.4%) at grade 1, 35 (12.5%) at grade 2, 42 (15.1%) at grade 3, 69 (24.7%) at grade 4, and 85 (30.5%) at grade 5. A total of 93 disks met the criteria for a symptomatic disk. The extent of annular disruption and the rate of symptomatic disks correlated significantly (P<.001). The highest symptomatic disk rate was observed in grade 4 disks. Of 93 symptomatic disks, 88 (94.6%) showed annular disruption of grade 3 or greater. Disks with grades 0 to 2 and grades 3 to 5 annular disruption differed significantly when the mean NRS relative to intradiskal pressure was compared (P<.001). Comparing the disk type of symptomatic disks at each annular disruption grade, there was a decreasing trend of low pressure sensitive disks relative to the extent of annular disruption (62.5% at grade 3, 39.4% at grade 4, 34.2% at grade 5).

CONCLUSIONS

Annular disruption reaching the outer annulus fibrosus is a key factor in pain generation. Disk morphology, including annular disruptions extending beyond the outer annulus, may permit increased diskography specificity.