Review the more recent literature specific to discography from the work of Carragee who revisited the Walsh et al, '90 study with a more appropriately aged control group makes even stronger the AHCPR Guide #14 methodological review of the literature, found reliable review at 7 years after being published.
Panel findings and recommendations:
- Discography is invasive, and its use is not recommended for assessing patients with low back pain. Interpretation is equivocal, and complications can be avoided with other noninvasive techniques.
(Strength of Evidence
- Due to increased potential risks, CT-discography is not recommended over other imaging studies (MRI, CT) for assessing patients with suspected nerve root compression due to lumbar disc hernia.
(Strength of Evidence
Summary of Findings. Although discography seeks to identify internal changes in the disc based on evaluation of a discogram and pain response on disc injection, the disease process is not clear (the internal disc disruption), and how to use the information for low back problems is not clear. The main reason put forward for using discography appears to be to determine the levels at which spinal fusion will be successful in patients with persistent low back problems (due to discogenic disease). This assumes the controversial premise of a "painful disc syndrome" which has not yet been adequately documented.
In summary, there is limited evidence that discography can help select patients who would benefit from spinal fusion and no evidence that it is helpful in patients with low back problems. Potential serious risks from discography, including disc infection, have been identified. The use of discography or CT
-discography to diagnose herniated discs appears to offer no significant advantage over other imaging methods with less potential risk of harm.
Discography controversy, especially concerning the specificity of symptom response, continued after the 1994 AHCPR Guide #14 until subsequent data was far less supportive. The award winning work of Dr. Eugene Carragee, et al, in articles 12/99-12/00 further precluded justification for the invasive nature of the technique, studying concordance, HIZ, safety and false positive risk as well as a `04 paper of not distinguishing severity of symptoms or being predictive for a reasonable surgical outcome.
Carragee et al, reconsidered the Walsh et al, with a more appropriate control group addressing: False-positive findings on lumbar discography (too high). Reliability of subjective concordance assessment during provocative disc injection (low). The rates of false-positive lumbar discography in select patients without low back symptoms (no prior back symptoms). Can discography cause long-term back symptoms in previously asymptomatic subjects (Yes)? Lumbar high-intensity zone and discography in subjects without low back problems (not predictive). Provocative discography in volunteer subjects with mild persistent low back pain (could not be differentiated from disabled). Prospective controlled study of the predicting development of LBP in previously asymptomatic subjects undergoing experimental discography (didn't).
Since discograms are commonly anatomically positive at young age groups, the poor specificity of symptom reproduction makes it difficult anymore to place discography in the experimental category let alone consider it a scientifically reliable technique. Thus, it bodes poorly for the procedures for which they are supposedly diagnostic - (IDET and lumbar fusion for internal disk derangement where outcomes are quite paltry). Madan et al., 2002 study found no difference in outcome from spinal fusion with or without pre- operative discography. The issue of discography as a diagnostic tool to identify correctable lesions in the disk has since been put to bed by Carragee et al.,`06. This prospective comparison of fusion outcomes based on "idea discography" patients vs. spondylolisthesis meeting "Posner criteria" for instability. Excellent surgical fusion results (no daily analgesia and return to usual work) using "ideal instability" indications was 72% compared to 26.6% for "ideal discography" where Minimally acceptable results (no narcotics and return to some work) were 43% and 57% poor results (requiring narcotics and unable to work) from fusion seems unacceptable relative to the surgical complication risks. Excellent surgical fusion results (no daily analgesia and return to usual work) using "ideal instability" indications was 72% compared to 26.6% for "ideal discography" indications. Minimally acceptable results (no narcotics and return to some work) or better were 91% and 43% respectively. A 57% poor results (requiring narcotics and unable to work) from fusion based upon ideal discography seems unacceptable relative to the surgical complication risks compared to 9% fused for Posner criteria of instability. Might the criteria seem to strict consider Carragee et al.`03 assessment of the minimally acceptable expectations of patients awaiting spinal fusion for presumed diskogenic pain. Greater than 90% of the patients wanted at least, 1. return to some gainful employment, 2. narcotic discontinuation, and 3. high physical functioning level. According to the available literature, such good results are uncommon after disk surgery based upon discography in patients with persistent disabling back pain (Fritzell`01, Brox`03, Fairbank`05, Pauza`04, Freeman`05, Carragee`06).
Best put in a rather lenient review of the literature on discography by Buenaventura et al.`07, "In the interim (until future research is available), questioning the validity of discography warrants questioning the role of the intervertebral disc as a discrete pain generator (which is obvious in the controlled trials on fusion and IDET) or more specifically, challenges the concept of symptomatic internal disc disruption. If one considers discography to be a useless test, then one may have to abandon the concept of the IVD as a discrete pain generator and abandon the pursuit of intradiscal therapies, whether surgical or non-surgical". It seems prudent to take heed considering the results.
SRC Spinemate - only used or reproduced with written permission from SResourceC@aol.com