In their excellent meta-analysis of the literature on spinal manipulation for the treatment of low-back pain, Shekelle and colleagues [1] distinguish between long-lever rotational manipulations of the lumbar spine and the specific short-lever arm techniques more common to chiropractic practice. All studies in the meta-analysis were done in the medical or physiotherapeutic setting, and most appeared to involve long-lever rotational manipulation of the lumbar spine. The implication that all manipulation has equal value is not consistent with the diverse techniques available.

Although the study by Meade and colleagues [2] received the fourth highest quality score and involved nearly 41% (608 of 1500) of all patients who have participated in clinical trials to date, Shekelle and coworkers [1] virtually ignore this study and state that this "was not a study of manipulation per se but rather a study of ‘chiropractic care’ compared with ‘medical care’ for patients with a variety of low-back pain syndromes." The medical care mainly involved Maitland physiotherapeutic manipulations of the lumbar spine, and the chiropractic care showed a statistically significant long-term benefit.

Five studies about chronic low-back pain specifically were reviewed. Because two of the studies involved additional therapies given to the patients who received spinal manipulation, these studies were not scrutinized. One study [3] was discarded because 84% of the patients also had sciatic nerve irritation. Surprisingly, this study was also excluded from the analysis of low-back pain with sciatic nerve root irritation [1].

However, Shekelle and colleagues' modest conclusion that insufficient data exist to support or refute the efficacy of spinal manipulation for chronic low-back pain is correct. Their conclusion that spinal manipulation should not be recommended for patients with sciatic irritation is based on the dearth of literature on the subject. Yet, by their own assessment, the risk for complications from spinal manipulation is relatively low, and none of the 1500 study patients had any complications (including those with sciatic nerve irritation). Whereas the major treatment that chiropractors administer is spinal manipulation, to state that they should no longer perform manipulation on patients with low-back pain and sciatica is premature. It is also in contrast to the bulk of the appropriateness ratings of the expert panel of chiropractors convened by the RAND Corporation [4]. It would have been more appropriate to state that little information exists to support or refute the efficacy of spinal manipulation in patients with low-back pain and sciatica.