Aims. We compared decompression alone to decompression with fusion surgery for lumbar spinal stenosis, with or without degenerative spondylolisthesis (DS). The aim was to evaluate if five-year outcomes differed between the groups. The two-year results from the same trial revealed no differences. Methods. The Swedish Spinal Stenosis Study was a multicentre randomized controlled trial with recruitment from September 2006 to February 2012. A total of 247 patients with one- or two-level central lumbar spinal stenosis, stratified by the presence of DS, were randomized to decompression alone or decompression with fusion. The five-year Oswestry Disability Index (ODI) was the primary outcome. Secondary outcomes were the EuroQol five-dimension questionnaire (EQ-5D), visual analogue scales for back and leg pain, and patient-reported satisfaction, decreased pain, and increased walking distance. The reoperation rate was recorded. Results. Five-year follow-up was completed by 213 (95%) of the eligible patients (mean age 67 years; 155 female (67%)). After five years, ODI was similar irrespective of treatment, with a mean of 25 (SD 18) for decompression alone and 28 (SD 22) for decompression with fusion (p = 0.226). Mean EQ-5D was higher for decompression alone than for fusion (0.69 (SD 0.28) vs 0.59 (SD 0.34); p = 0.027). In the no-DS subset, fewer patients reported decreased leg pain after fusion (58%) than with decompression alone (80%) (relative risk (RR) 0.71 (95% confidence interval (CI) 0.53 to 0.97). The frequency of subsequent spinal surgery was 24% for decompression with fusion and 22% for decompression alone (RR 1.1 (95% CI 0.69 to 1.8)). Conclusion. Adding fusion to decompression in spinal stenosis surgery, with or without spondylolisthesis, does not improve the five-year ODI, which is consistent with our two-year report. Three secondary outcomes that did not differ at two years favoured decompression alone at five years. Our results support decompression alone as the preferred method for operating on spinal stenosis. Cite this article: Bone Joint J 2024;106-B(7):705–712

Aims. Lumbar spinal stenosis (LSS) is a common skeletal system disease that has been partly attributed to genetic variation. However, the correlation between genetic variation and pathological changes in LSS is insufficient, and it is difficult to provide a reference for the early diagnosis and treatment of the disease. Methods. We conducted a transcriptome-wide association study (TWAS) of spinal canal stenosis by integrating genome-wide association study summary statistics (including 661 cases and 178,065 controls) derived from Biobank Japan, and pre-computed gene expression weights of skeletal muscle and whole blood implemented in FUSION software. To verify the TWAS results, the candidate genes were furthered compared with messenger RNA (mRNA) expression profiles of LSS to screen for common genes. Finally, Metascape software was used to perform enrichment analysis of the candidate genes and common genes. Results. TWAS identified 295 genes with permutation p-values < 0.05 for skeletal muscle and 79 genes associated for the whole blood, such as RCHY1 (PTWAS = 0.001). Those genes were enriched in 112 gene ontology (GO) terms and five Kyoto Encyclopedia of Genes and Genomes pathways, such as ‘chemical carcinogenesis - reactive oxygen species’ (LogP value = −2.139). Further comparing the TWAS significant genes with the differentially expressed genes identified by mRNA expression profiles of LSS found 18 overlapped genes, such as interleukin 15 receptor subunit alpha (IL15RA) (PTWAS = 0.040, PmRNA = 0.010). Moreover, 71 common GO terms were detected for the enrichment results of TWAS and mRNA expression profiles, such as negative regulation of cell differentiation (LogP value = −2.811). Conclusion. This study revealed the genetic mechanism behind the pathological changes in LSS, and may provide novel insights for the early diagnosis and intervention of LSS. Cite this article: Bone Joint Res 2023;12(6):387–396

Aims. The aims of this study were first, to determine if adding fusion to a decompression of the lumbar spine for spinal stenosis decreases the rate of radiological restenosis and/or proximal adjacent level stenosis two years after surgery, and second, to evaluate the change in vertebral slip two years after surgery with and without fusion. Methods. The Swedish Spinal Stenosis Study (SSSS) was conducted between 2006 and 2012 at five public and two private hospitals. Six centres participated in this two-year MRI follow-up. We randomized 222 patients with central lumbar spinal stenosis at one or two adjacent levels into two groups, decompression alone and decompression with fusion. The presence or absence of a preoperative spondylolisthesis was noted. A new stenosis on two-year MRI was used as the primary outcome, defined as a dural sac cross-sectional area ≤ 75 mm. 2. at the operated level (restenosis) and/or at the level above (proximal adjacent level stenosis). Results. A total of 211 patients underwent surgery at a mean age of 66 years (69% female): 103 were treated by decompression with fusion and 108 by decompression alone. A two-year MRI was available for 176 (90%) of the eligible patients. A new stenosis at the operated and/or adjacent level occurred more frequently after decompression and fusion than after decompression alone (47% vs 29%; p = 0.020). The difference remained in the subgroup with a preoperative spondylolisthesis, (48% vs 24%; p = 0.020), but did not reach significance for those without (45% vs 35%; p = 0.488). Proximal adjacent level stenosis was more common after fusion than after decompression alone (44% vs 17%; p < 0.001). Restenosis at the operated level was less frequent after fusion than decompression alone (4% vs 14%; p = 0.036). Vertebral slip increased by 1.1 mm after decompression alone, regardless of whether a preoperative spondylolisthesis was present or not. Conclusion. Adding fusion to a decompression increased the rate of new stenosis on two-year MRI, even when a spondylolisthesis was present preoperatively. This supports decompression alone as the preferred method of surgery for spinal stenosis, whether or not a degenerative spondylolisthesis is present preoperatively. Cite this article: Bone Joint J 2022;104-B(12):1343–1351

Aims. Repeated lumbar spine surgery has been associated with inferior clinical outcomes. This study aimed to examine and quantify the impact of this association in a national clinical register cohort. Methods. This is a population-based study from the Norwegian Registry for Spine surgery (NORspine). We included 26,723 consecutive cases operated for lumbar spinal stenosis or lumbar disc herniation from January 2007 to December 2018. The primary outcome was the Oswestry Disability Index (ODI), presented as the proportions reaching a patient-acceptable symptom state (PASS; defined as an ODI raw score ≤ 22) and ODI raw and change scores at 12-month follow-up. Secondary outcomes were the Global Perceived Effect scale, the numerical rating scale for pain, the EuroQoL five-dimensions health questionnaire, occurrence of perioperative complications and wound infections, and working capability. Binary logistic regression analysis was conducted to examine how the number of previous operations influenced the odds of not reaching a PASS. Results. The proportion reaching a PASS decreased from 66.0% (95% confidence interval (CI) 65.4 to 66.7) in cases with no previous operation to 22.0% (95% CI 15.2 to 30.3) in cases with four or more previous operations (p < 0.001). The odds of not reaching a PASS were 2.1 (95% CI 1.9 to 2.2) in cases with one previous operation, 2.6 (95% CI 2.3 to 3.0) in cases with two, 4.4 (95% CI 3.4 to 5.5) in cases with three, and 6.9 (95% CI 4.5 to 10.5) in cases with four or more previous operations. The ODI raw and change scores and the secondary outcomes showed similar trends. Conclusion. We found a dose-response relationship between increasing number of previous operations and inferior outcomes among patients operated for degenerative conditions in the lumbar spine. This information should be considered in the shared decision-making process prior to elective spine surgery. Cite this article: Bone Joint J 2023;105-B(4):422–430

Pain catastrophising is an adverse coping mechanism, involving an exaggerated response to anticipated or actual pain.

The purpose of this study was to investigate the influence of pain ‘catastrophising’, as measured using the pain catastrophising scale (PCS), on treatment outcomes after surgery for lumbar spinal stenosis (LSS).

A total of 138 patients (47 men and 91 women, mean age 65.9; 45 to 78) were assigned to low (PCS score < 25, n = 68) and high (PCS score ≥ 25, n = 70) PCS groups. The primary outcome measure was the Oswestry Disability Index (ODI) 12 months after surgery. Secondary outcome measures included the ODI and visual analogue scale (VAS) for back and leg pain, which were recorded at each assessment conducted during the 12-month follow-up period

The overall changes in the ODI and VAS for back and leg pain over a 12-month period were significantly different between the groups (ODI, p < 0.001; VAS for back pain, p < 0.001; VAS for leg pain, p = 0.040). The ODI and VAS for back and leg pain significantly decreased over time after surgery in both groups (p < 0.001 for all three variables). The patterns of change in the ODI and VAS for back pain during the follow-up period significantly differed between the two groups, suggesting that the PCS group is a potential treatment moderator. However, there was no difference in the ODI and VAS for back and leg pain between the low and high PCS groups 12 months after surgery.

In terms of minimum clinically important differences in ODI scores (12.8), 22 patients (40.7%) had an unsatisfactory surgical outcome in the low PCS group and 16 (32.6%) in the high PCS group. There was no statistically significant difference between the two groups (p = 0.539).

Pre-operative catastrophising did not always result in a poor outcome 12 months after surgery, which indicates that this could moderate the efficacy of surgery for LSS.

Cite this article: Bone Joint J 2015;97-B:1546–54.

Surgical decision-making in lumbar spinal stenosis involves assessment of clinical parameters and the severity of the radiological stenosis. We suspected that surgeons based surgical decisions more on dural sac cross-sectional area (DSCA) than on the morphology of the dural sac. We carried out a survey among members of three European spine societies. The axial T2-weighted MR images from ten patients with varying degrees of DSCA and morphological grades according to the recently described morphological classification of lumbar spinal stenosis, with DSCA values disclosed in half the assessed images, were used for evaluation. We provided a clinical scenario to accompany the images, which were shown to 142 responding physicians, mainly orthopaedic surgeons but also some neurosurgeons and others directly involved in treating patients with spinal disorders. As the primary outcome we used the number of respondents who would proceed to surgery for a given DSCA or morphological grade. Substantial agreement among the respondents was observed, with severe or extreme stenosis as defined by the morphological grade leading to surgery. This decision was not dependent on the number of years in practice, medical density or specialty. Disclosing the DSCA did not alter operative decision-making. In all, 40 respondents (29%) had prior knowledge of the morphological grading system, but their responses showed no difference from those who had not. This study suggests that the participants were less influenced by DSCA than by the morphological appearance of the dural sac. . Classifying lumbar spinal stenosis according to morphology rather than surface measurements appears to be consistent with current clinical practice

Objectives. Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. Methods. CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm pedicle-lengthening osteotomies at L4 and/or L5. One-way analysis of variance was used to examine between-group differences. Results. In the intact state, SVC and NFD were significantly larger in the control group compared with the LSS groups (P<0.05). After lengthening at L4, the percentage increase in SCV (per millimetre) was LRS>CCS>FS>Control. After lengthening at L5 and L4-L5, the percentage increase in SCV (per millimetre) was LRS>FS>CCS>Control. After lengthening at L4 and L4-L5, the percentage increase in NFD (per millimetre) was FS>CCS>LRS>Control. After lengthening at L5, the percentage increase in NFD (per millimetre) was CCS>LRS>control>FS. Conclusions. LRS patients are the most suitable candidates for treatment with pedicle-lengthening osteotomy. Lengthening L4 pedicles produced larger percentage increases in NFD than lengthening L5 pedicles (p < 0.05). Lengthening L4 pedicles may be the most effective option for relieving foraminal compression in LSS patients. Cite this article: P. Li, L. Qian, W. D. Wu, C. F. Wu, J. Ouyang. Impact of pedicle-lengthening osteotomy on spinal canal volume and neural foramen size in three types of lumbar spinal stenosis. Bone Joint Res 2016;5:239–246. DOI: 10.1302/2046-3758.56.2000469

Thirty-one patients who had been treated surgically for lumbar spinal stenosis between 1968 and 1978 at the Norfolk and Norwich Hospital have been personally reviewed. In 28 patients (90 per cent) degenerative change in the lumbar spine had been the principal aetiological factor; the other three had idiopathic developmental lumbar spinal stenosis. In 17 patients (55 per cent) the result was classified as good, although a total of 26 patients (84 per cent) were satisfied. In patients with degenerative changes, one important reason for failure was inadequate decompression; re-operation in this group seemed worthwhile. The good results of operation for lumbar spinal stenosis were characterised by rapid resolution of pain in the leg

The August 2023 Spine Roundup360 looks at: Changes in paraspinal muscles correspond to the severity of degeneration in patients with lumbar stenosis; Steroid injections are not effective in the prevention of surgery for degenerative cervical myelopathy; A higher screw density is associated with fewer mechanical complications after surgery for adult spinal deformity; Methylprednisolone following minimally invasive lumbar decompression: a large prospective single-institution study; Occupancy rate of pedicle screw below 80% is a risk factor for upper instrumented vertebral fracture following adult spinal deformity surgery; Deterioration after surgery for degenerative cervical myelopathy: an observational study from the Canadian Spine Outcomes and Research Network

Aims. The aim of this study was to determine the influence of developmental spinal stenosis (DSS) on the risk of re-operation at an adjacent level. Patients and Methods. This was a retrospective study of 235 consecutive patients who had undergone decompression-only surgery for lumbar spinal stenosis and had a minimum five-year follow-up. There were 106 female patients (45.1%) and 129 male patients (54.9%), with a mean age at surgery of 66.8 years (. sd. 11.3). We excluded those with adult deformity and spondylolisthesis. Presenting symptoms, levels operated on initially and at re-operation were studied. MRI measurements included the anteroposterior diameter of the bony spinal canal, the degree of disc degeneration, and the thickness of the ligamentum flavum. DSS was defined by comparative measurements of the bony spinal canal. Risk factors for re-operation at the adjacent level were determined and included in a multivariate stepwise logistic regression for prediction modelling. Odds ratios (ORs) with 95% confidence intervals were calculated. Results. Of the 235 patients, 21.7% required re-operation at an adjacent segment. Re-operation at an adjacent segment was associated with DSS (p = 0.026), the number of levels decompressed (p = 0.008), and age at surgery (p = 0.013). Multivariate regression model (p < 0.001) controlled for other confounders showed that DSS was a significant predictor of re-operation at an adjacent segment, with an adjusted OR of 3.93. Conclusion. Patients with DSS who have undergone lumbar spinal decompression are 3.9 times more likely to undergo future surgery at an adjacent level. This is a poor prognostic indicator that can be identified prior to index decompression surgery

Cross-sectional studies of the lumbar spinal canal were performed by computerised tomography in asymptomatic subjects and in patients with myelographic and clinical findings suggestive of lumbar stenosis. In most cases stenosis was found to be developmental or combined in nature. Computerised tomography is a useful adjunct to myelography in the evaluation of lumbar stenosis as it enables an accurate assessment to be made of the type, degree and extent of narrowing of the vertebral canal

Aims. To report the development of the technique for minimally invasive lumbar decompression using robotic-assisted navigation. Methods. Robotic planning software was used to map out bone removal for a laminar decompression after registration of CT scan images of one cadaveric specimen. A specialized acorn-shaped bone removal robotic drill was used to complete a robotic lumbar laminectomy. Post-procedure advanced imaging was obtained to compare actual bony decompression to the surgical plan. After confirming accuracy of the technique, a minimally invasive robotic-assisted laminectomy was performed on one 72-year-old female patient with lumbar spinal stenosis. Postoperative advanced imaging was obtained to confirm the decompression. Results. A workflow for robotic-assisted lumbar laminectomy was successfully developed in a human cadaveric specimen, as excellent decompression was confirmed by postoperative CT imaging. Subsequently, the workflow was applied clinically in a patient with severe spinal stenosis. Excellent decompression was achieved intraoperatively and preservation of the dorsal midline structures was confirmed on postoperative MRI. The patient experienced improvement in symptoms postoperatively and was discharged within 24 hours. Conclusion. Minimally invasive robotic-assisted lumbar decompression utilizing a specialized robotic bone removal instrument was shown to be accurate and effective both in vitro and in vivo. The robotic bone removal technique has the potential for less invasive removal of laminar bone for spinal decompression, all the while preserving the spinous process and the posterior ligamentous complex. Spinal robotic surgery has previously been limited to the insertion of screws and, more recently, cages; however, recent innovations have expanded robotic capabilities to decompression of neurological structures. Cite this article: Bone Jt Open 2024;5(9):809–817

We reviewed 40 patients treated surgically for lumbar stenosis at an average time of 8.6 years after operation. In 32, total laminectomy had been performed and in eight bilateral laminotomy, both at one or more levels. Of the 16 patients with degenerative spondylolisthesis, ten had had a concomitant spinal fusion. Patients were assigned to one of four groups according to the amount of bone regrowth: group 0 had no regrowth and groups I, II, and III, had mild, moderate or marked regrowth, respectively. Only 12% of the patients showed no bone regrowth; 48% were assigned to group I, 28% to group II and 12% to group III. Imaging studies showed varying degrees of recurrent stenosis in patients with moderate or marked bone regrowth. All patients with degenerative spondylolisthesis showed bone regrowth, which was more severe in those who had not had a fusion. The clinical results were satisfactory in most of the patients with mild or no bone regrowth and significantly less good in those with moderate or marked regrowth. In the group with degenerative spondylolisthesis, the proportion of satisfactory results was significantly higher in patients who had had spinal fusion. The long-term results of surgery for lumbar stenosis depend both upon the amount of bone regrowth and the degree of postoperative vertebral stability

We investigated the pre-operative and one-year post-operative health-related quality of life (HRQoL) outcome by using a Euroqol (EQ-5D) questionnaire in 230 patients who underwent surgery for lumbar spinal stenosis. Data were obtained from the National Swedish Registry for operations on the lumbar spine between 2001 and 2002. We analysed the pre- and postoperative quality of life data, age, gender, smoking habits, pain and walking ability. The relative differences were compared to a Swedish EQ-5D population survey. The mean age of the patients was 66 years, and there were 123 females (53%). Before the operation 62 (27%) of the patients could walk more than 500 m. One year after the operation 150 (65%) were able to walk 500 m or more. The mean EQ-5D score improved from 0.36 to 0.64, and the HRQoL improved in 184 (80%) of the patients. However, they did not reach the level reported by a matched population sample (mean difference 0.18). Women had lower pre- and post-operative EQ-5D scores than men. Severe low back pain was a predictor for a poor outcome

Whether to combine spinal decompression with fusion in patients with symptomatic lumbar spinal stenosis remains controversial. We performed a cohort study to determine the effect of the addition of fusion in terms of patient satisfaction after decompressive spinal surgery in patients with and without a degenerative spondylolisthesis. The National Swedish Register for Spine Surgery (Swespine) was used for the study. Data were obtained for all patients in the register who underwent surgery for stenosis on one or two adjacent lumbar levels. A total of 5390 patients fulfilled the inclusion criteria and completed a two-year follow-up. Using multivariable models the results of 4259 patients who underwent decompression alone were compared with those of 1131 who underwent decompression and fusion. The consequence of having an associated spondylolisthesis in the operated segments pre-operatively was also considered. At two years there was no significant difference in patient satisfaction between the two treatment groups for any of the outcome measures, regardless of the presence of a pre-operative spondylolisthesis. Moreover, the proportion of patients who required subsequent further lumbar surgery was also similar in the two groups. In this large cohort the addition of fusion to decompression was not associated with an improved outcome. Cite this article: Bone Joint J 2013;95-B:960–5

We carried out a retrospective review of 155 patients with lumbar spinal stenosis who had been treated surgically and followed up regularly: 77 were evaluated at a mean of 6.5 years (5 to 8) after surgery by two independent observers. The outcome was assessed using the scoring system of Roland and Morris, and the rating system of Prolo, Oklund and Butcher. Instability was determined according to the criteria described by White and Panjabi. A significant decrease in low back pain and disability was seen. An excellent or good outcome was noted in 79% of patients; 9% showed secondary radiological instability. Surgical decompression is a safe and efficient procedure. In the absence of preoperative radiological evidence of instability, fusion is not required

We reviewed 25 diabetic (mean age 68 years) and 25 non-diabetic patients (mean age 71 years) who had undergone decompression for lumbar spinal stenosis at a mean of 3.4 years after operation to determine whether diabetes affected the outcome of surgery. The preoperative symptoms were similar in the two groups except that an abrupt onset of symptoms, the presence of night pain and the absence of any posture-related pain relief were recorded only by diabetic patients. Nerve-conduction velocity was slowed in 80% of the diabetic and in 25% of the non-diabetic patients. Peripheral vascular deficiency was diagnosed in 20% of patients with diabetes and in 4% of non-diabetics. The outcome of surgery was similarly successful in the two groups. Mistaken preoperative diagnosis was the cause of failure in three diabetic patients, two with diabetic neuropathy and one with diabetic angiopathy

We assigned 67 patients with central lumbar stenosis alternately to either multiple laminotomy or total laminectomy. The protocol, however, allowed multiple laminotomy to be changed to total laminectomy if it was thought that the former procedure might not give adequate neural decompression. There were therefore three treatment groups: group I consisting of 26 patients submitted to multiple laminotomy; group II, 9 patients scheduled for laminotomy but submitted to laminectomy; and group III, 32 patients scheduled for, and submitted to, laminectomy. The mean follow-up was 3.7 years. Bilateral laminotomy at two or three levels required a longer mean operating time than total laminectomy at an equal number of levels. The mean blood loss at surgery and the clinical results did not differ in the three groups. The mean subjective improvement score for low back pain was higher in group I but there was also a higher incidence of neural complications in this group. No patient in group I had postoperative vertebral instability, whereas this occurred in three patients in groups II and III, who had lumbar scoliosis or degenerative spondylolisthesis preoperatively. Multiple laminotomy is recommended for all patients with developmental stenosis and for those with mild to moderate degenerative stenosis or degenerative spondylolisthesis. Total laminectomy is to be preferred for patients with severe degenerative stenosis or marked degenerative spondylolisthesis