Swedish group report substantial long-term pain following lumbar fusion for chronic low back pain

1324

Long-term 13-year results from the Swedish Lumbar Spine Study Group indicate that although lumbar fusion can still be considered a valid treatment option for chronic low back pain, substantial postoperative pain and disability should be expected. The results were presented at EUROSPINE 2015 (2–4 September, Copenhagen, Denmark).

Rune Hedlund, Sahlgrenska University Hospital, University of Gothenburg, Sweden, who presented the data, said that “Lumbar fusion for non-specific low back pain is still the most controversial subject in spine surgery,” with previous studies producing conflicting data on the efficacy of fusion compared with standard physiotherapy.

In an effort to bring some clarity the ongoing debate, Hedlund and his colleagues in the Swedish Lumbar Spine Study Group enrolled 294 patients (144 female, 150 male) with chronic low back pain of at least two years’ duration with radiographs showing degenerative disc disease. The patients were randomised to either lumbar fusion or standard physiotherapy. Hedlund only presented patients following randomisation, and noted that 26% of physiotherapy patients were eventually operated on, but were not included in the fusion group.

“This represents the largest study with the longest follow up thus far conducted, and is also the one with highest follow up rate so far presented—92%—unique for a long-term study”, Hedlund told Spinal News International. “This allows far stronger conclusions than in previous studies, which are characterised by low follow up rates.”

The primary outcome measure used was patient global assessment. Also used were Oswestry Disability Index (ODI) scores, visual analogue scale (VAS) pain scores, Zung depression index, medication use, pain frequency and ability to work.

Sixty-five per cent of fusion patients reported either “better” (39%) or “much better” (26%) global assessment scores compared to just 37% of the patients in the physiotherapy group (26% “better” and 11% “much better”) (p=0.044). However, Hedlund reported that both groups improved in all secondary outcome variables to similar levels at 13 years. ODI scores for the fusion group show an improvement of 11 points, while VAS back pain scores improved by 18 points. Working status (full- or part-time work) did not differ significantly between the two groups, improving from 21% at baseline to 38% after 13 years in the fusion group, compared with 24% up to 41% in the physiotherapy group. Furthermore, 43% of patients in the fusion group and 41% in the physiotherapy group reported “always” having pain (p=0.95) at 13-year follow up.

Compared with previous studies, the Group’s results found “a better global assessment for fusion than for conservative treatment in contrast to a combined British-Norwegian study,” (Mannion et al 2013). Hedlund also told delegates that the marginal improvements in pain levels and disability found by his Group were similar to those found by Mannion et al, as well as to those found by other systematic reviews.

“Patient global assessment was better for the fusion group than for the physiotherapy group, despite similar pain, functional ability and working status,” said Hedlund. “From a patient’s perspective, lumbar fusion can still be considered a valid treatment option for chronic low back pain. However, substantial remaining pain and disability should be expected after fusion.”