Tag Archive | Lumbar

JBJS Classics: Wiltse’s Paraspinal Muscle-Splitting Approach

JBJS Classics Logo.pngOrthoBuzz regularly brings you a current commentary on a “classic” article from The Journal of Bone & Joint Surgery. These articles have been selected by the Editor-in-Chief and Deputy Editors of The Journal because of their long-standing significance to the orthopaedic community and the many citations they receive in the literature. Our OrthoBuzz commentators highlight the impact that these JBJS articles have had on the practice of orthopaedics. Please feel free to join the conversation by clicking on the “Leave a Comment” button in the box to the left.

Almost 50 years ago, in a classic 1968 JBJS paper, Leon Wiltse and co-authors described a novel and innovative access route to the lumbar spine. At that time, the vast majority of approaches to the lumbar spine were performed through midline incisions. Wiltse´s approach, however, utilized a more lateral access route to the spine. In this beautifully illustrated paper, the authors described a curved incision of the fascia and the skin with direct access to the transverse processes, pedicles, and the lateral masses.

The advantages of this novel access were multifold. Although wide midline laminectomies represented the gold-standard decompression technique at that time, the lateral approach served to avoid a more challenging and risky midline revision access, adding an elegant access for salvage procedures. Two goals of Wiltse’s approach were to achieve solid, posterolateral fusions and to decompress the neural structures. Graft harvest from the posterior iliac crest was easily facilitated with this approach.

Additional advantages included reduced blood loss and less muscle ischemia, and the preservation of spinous processes and intra-/supraspinous ligaments, which served to maintain the stability of the lumbar spine. The main downside was the necessity of performing two skin incisions as opposed to just one midline incision.

Since its introduction, Wiltse´s approach and the anatomic planes have been studied in great detail.1,2 Considering the vast developments in spine surgery over the last years and decades, the Wiltse approach has stood the test of time, as it still represents one of the main access routes to the lumbar spine that any skilled spine surgeon needs to master.

With the arrival of instrumentation, Wiltse´s approach was later employed in interbody fusion and minimally invasive transforaminal lumbar interbody fusion (TLIF) techniques, as it allowed direct access to the pedicles and the disc space. It has also been used for various techniques of direct pars repair.3

With the addition of some minor modifications, Wiltse´s approach still reflects the main access for minimally invasive, microsurgical treatment of foraminal and extraforaminal disc herniations, including bony decompression of the neuroforamen.4 The far lateral access permits sufficient decompression of the exiting nerve roots while preserving the facet joints, which serves to avoid more invasive fusion techniques for a considerable number of patients.

Overall, Wiltse´s innovative approach advanced spinal care by reducing access–related morbidity. Dr. Wiltse passed away at age 92 in 2005. His major achievements in spine surgery and his great accomplishments will remain in our memories and will continue to impact spine surgery over the coming decades.

Christoph J. Siepe, MD
JBJS Deputy Editor

References

  1. Vialle R, Court C, Khouri N, et al. Anatomical study of the paraspinal approach to the lumbar spine. Eur Spine J. 2005;14(4):366-71.
  2. Palmer DK, Allen JL, Williams PA, et al. Multilevel magnetic resonance imaging analysis of multifidus-longissimus cleavage planes in the lumbar spine and potential clinical applications to Wiltse’s paraspinal approach. Spine (Phila Pa 1976). 2011;36(16):1263-7.
  3. Xing R, Dou Q, Li X, et al. Posterior Dynamic Stabilization With Direct Pars Repair via Wiltse Approach for the Treatment of Lumbar Spondylolysis: The Application of a Novel Surgery. Spine (Phila Pa 1976). 2016;41(8):E494-502.
  4. Mehren C, Siepe CJ. Neuroforaminal decompression and intra-/extraforaminal discectomy via a paraspinal muscle-splitting approach. Eur Spine J. 2016.

Treatments for Lumbar Spinal Stenosis Compared

Two interesting investigations into lumbar spinal stenosis (LSS) appeared in the general medical literature recently.

—A registry-based observational study of nearly 900 patients in the BMJ found that microdecompression techniques were as effective as open laminectomy in improving disability scores 12 months after surgery. The two techniques yielded similar quality-of-life scores at the one-year point, but the microdecompression patients had shorter hospital stays.

—In Annals of Internal Medicine, a multisite randomized study of 170 patients 50 or older with lumbar spinal stenosis found that those receiving surgical decompression and those receiving physical therapy (2 PT visits per week for six weeks focused on lumbar flexion and general conditioning) had essentially the same functional outcomes at time points ranging from 10 weeks to two years after enrollment. However, 57% of patients assigned to PT crossed over to surgery—some due to high copays for physical therapy, said study co-author Anthony Delitto, PT. In an editorial accompanying the study, JBJS Deputy Editor for Methodology and Biostatistics Jeffrey Katz, MD, concluded, “Because long-term outcomes are similar for both treatments yet short-term risks differ, patient preferences should weigh heavily in the decision of whether to have surgery for LSS.”

JBJS Classics: Correlating Lumbar MRIs with Clinical Findings

JBJS-Classics-logoEach month during the coming year, OrthoBuzz will bring you a current commentary on a “classic” article from The Journal of Bone & Joint Surgery. These articles have been selected by the Editor-in-Chief and Deputy Editors of The Journal because of their long-standing significance to the orthopaedic community and the many citations they receive in the literature. Our OrthoBuzz commentators will highlight the impact that these JBJS articles have had on the practice of orthopaedics. Please feel free to join the conversation about these classics by clicking on the “Leave a Comment” button in the box to the left.

In 1989, a group of sixty-seven asymptomatic individuals with no history of back pain or sciatica underwent magnetic resonance scans of the lumbar spine. In a landmark 1990 JBJS study, Boden et al. reported that three neuroradiologists who had no clinical knowledge of the patients interpreted the images as being substantially abnormal in 28% of the cohort (19 individuals). More specifically, a herniated nucleus pulposus was identified in 24 % of these asymptomatic subjects. These “magnetic-resonance positive” findings were more prevalent in older subjects; abnormal MRI findings were identified in 57% of those aged 60 to 80 years.

Boden et al. concluded that so many MRI findings of substantial abnormalities in asymptomatic people “emphasized the dangers of predicating a decision to operate on the basis of diagnostic tests—even when a state-of-the-art modality is used—without precise correlation with clinical signs and symptoms.”

However, despite the findings of Boden et al., during the last five years of the 1990s, Medicare claims showed a 40% increase in spine-surgery rates, a 70% increase in fusion-surgery rates, and a two-fold increase in use of spinal implants. Although spine-fusion surgery has a well-established role in treating certain spinal diseases, a 2007 systematic review of several randomized trials indicated that the benefits of fusion surgery were limited when treating degenerative lumbar discs with back pain alone. This review suggested the need for more thorough selection of surgical candidates, which was a caution also implied by Boden et al.

Although the three neuroradiologists in the Boden et al. study largely agreed on the absence or presence of abnormal findings on the MRIs, in 2014 Fu et al. reported on the interrater and intrarater agreements by four reviewers of MRI findings from the lumbar spine of 75 subjects. Even though this study used standardized evaluation criteria, there was significant variability in both interrater and intrarater agreement among the reviewers. As the Boden et al. study did 25 years ago, this study demonstrated the diagnostic limitations of MRI interpretation for lumbar spinal diseases.

In 2001, JBJS published a paper by Borenstein et al. that was a seven-year follow-up study among the same asymptomatic subjects studied by Boden et al. Borenstein et al. found that the original 1989 scans of the lumbar spine were not predictive of the future development or duration of low back pain. This led Borenstein et al. to conclude—as Boden et al. did—that “clinical correlation is essential to determine the importance of abnormalities on magnetic resonance images.”

Many important subsequent studies were inspired by the original findings of Boden et al. in JBJS. Most of them emphasize that for lumbar-spine diagnoses, an MRI is only one (albeit important) piece of data; that interpretation of MRIs is variable; and that all imaging information must be correlated to the specific patient’s clinical condition.

Several studies and national surveys indicate that approximately a quarter of US adults report having had back pain during the past 3 months, making this a common clinical complaint. But the findings of Boden, et al. and subsequent studies remind us that surgery is not always the appropriate treatment.

Daisuke Togawa, MD, PhD

JBJS Deputy Editor