Decompression for Lumbar Stenosis May Also Improve Low Back Pain

By Marilynn Larkin

February 07, 2019

NEW YORK (Reuters Health) - Treating symptomatic lumbar stenosis with surgical decompression may also relieve associated low back pain (LBP), researchers say.

Shreya Srinivas, a senior fellow in spine surgery at Alder Hey Children's Hospital in Liverpool, UK and colleagues studied the effect of surgical intervention specifically on LBP in patients with lumbar stenosis.

Her team found "significant improvement in back pain after surgery for lumbar spine stenosis that is maintained for up to two years after the procedure," she said in an email to Reuters Health. "The proportion of patients who had no or minimal residual back pain also improved significantly.

Srinivas and colleagues analyzed data from the multicenter Canadian Spine Outcomes and Research Network on patients who had surgery for symptomatic lumbar stenosis without instability between 2014 and 2017. Patient-reported pain outcomes assessed with the Numeric Rating Scale (NRS) were collected at baseline and at three, 12, and 24 months after surgery.

As reported online January 18 in The Spine Journal, 1,221 patients (mean age, 64; 58% men) were included in the analysis. Baseline back pain scores were available in 1,133 (93%), and follow-up evaluations were available for 85% of those patients at three months, 72% at 12 months, and 73% at 24 months.

An improvement in back pain equal to or greater than the minimal clinical important difference (MCID) was achieved in 74% of patients at three months post-operatively, of whom 68% remained clinically significantly improved at two years.

As Srinivas noted, the proportion of patients with no or minimal residual back pain (NRS 0-2) also increased significantly from 7.5% at baseline to 46.4% at 12 months and 40.9% at 24 months

A higher number of patients reached the MCID for leg pain than for back pain initially (76% vs. 74%) and a similar trend was maintained at 24 months (70% vs. 68%).

Notably, at three months, 82.3% of patients who had improvement of their leg symptoms also had back pain improvement reaching MCID, as did 77% of patients at 24 months.

Preoperative factors that predicted sustained LBP improvement at 12 and 24 months post-surgery were absence of narcotic usage or compensation claims and greater LBP severity (high NRS).

Other factors, such as level of education and higher health state score, showed a weak association with improvement in LBP at three months, but were not predictive after that.

Neither the type of surgery (i.e., decompression alone versus fusion and decompression, or minimally invasive surgery versus open), nor the occurrence of intraoperative or postoperative adverse events, surgical time or length of stay were predictive factors.

"Patients who underwent surgical decompression predominantly had claudication-type symptoms; (the procedure) was not performed for back pain symptoms alone," said Srinivas, who was at the Vancouver Spine Surgery Institute in Canada during the study.

"Thus, the results are representative of real-life clinical practice and complement data from RCTs and other observational studies. Ultimately, this helps surgeons to manage patient expectations and counsel them about potential effects of surgical intervention on their symptoms," she concluded.

Dr. Payam Farjoodi, an orthopedic spine surgeon at the Spine Health Center at MemorialCare Orange Coast Medical Center in Fountain Valley, California, told Reuters Health in an email that the findings are "quite surprising."

"The current teaching is that decompressing the lumbar spine helps with leg symptoms - i.e., the referred pain that many patients feel shooting in the lower extremities with walking and activity. Typically, patients are counseled that this type of surgery does not address back complaints," he noted.

"The implications are significant," he said. "I think it is reasonable to counsel patients...that a lumbar decompression can lead to improved low back pain in addition to the relief of leg symptoms. This may encourage more patients to explore this as an option for treatment, rather than live with continued low back pain."

However, he noted, "One study rarely changes the course of treatment for all physicians. It is important to follow this study with other prospective, well done studies in order to validate the results. It certainly opens the door to evolving the current thinking about results following lumbar decompressive surgery."

"There can be other significant conditions that occur at the same time as lumbar stenosis which would not be appropriately treated with decompression and can in fact be worsened by that procedure," he added. "Instability, such as spondylolisthesis, can cause back pain that may require fusion in addition to a decompression alone. It is important to conduct a thorough evaluation before settling on a particular treatment."


Spine J 2019.