Aim

To evaluate efficacy of a one stage posterior approach in decompression and eradication of infection in TB spine.

Aim

To evaluate morbidity and outcome associated with lumbar spine decompression for central spinal stenosis in the elderly compared with younger age groups.

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.

Background: Iatrogenic instability can be produced by lumbar spine decompression surgery not only if decompression extends beyond the lateral border of pars but also if there is insufficient pars left at the end of the procedure resulting in its fracture and hence instability on weight bearing. Generally, it is considered to be safe in preventing iatrogenic instability if half of the facet joint is left intact during decompression surgeries.

Purpose: We aimed to answer the following questions. By removing half of the facets can we get adequate decompression of the nerve roots? Is there a difference at different levels in the lower lumbar spine? What is the inclination of the facet joint at each level and how does it affect the stability?

Material and Methods: We analysed 200 consecutive magnetic reasonance imaging (MRI) scans of the lumbosacral spine at L3/4, L4/5, and L5/S1 levels. We measured the difference in the distance from midline to the lateral border of the foramen and from midline to the middle of the facet joint at each level on either sides. The angle of the facet joint was also noted. The vertebral body diameters in both the sagittal and coronal plane were noted.

Results: At L3/4, the mean distance from the midline to the middle of facet joint was 15.5 +/−1.9 mm (11–23mm), while the mean distance from the midline to the foramen was 21.2 +/− 2.6 mm (13–28mm). At L4/5, the mean distance from the midline to the middle of facet joint was 18.1 +/−2.3 mm (13–25mm), while the mean distance from the midline to the foramen was 23.6 +/− 2.9 mm (16–34mm). At L5/S1, the mean distance from the mid-line to the middle of facet joint was 15.5 +/−1.9 mm (11–23mm), while the mean distance from the midline to the foramen was 26.8 +/− 2.9 mm (20–34mm). The angle of the facet joints at L3/4 is 35.90 +/− 7.40, while at L4/5 it is 43.20 +/− 8.00, and at L5/S1 it is 49.40 +/− 10.10.

Conclusion: The distance to the foramen from the level of the middle of the facet joints seem to be between 5–6mm at every level with the lateral border of the foramen being lateral to the middle of the facet joint. Hence, in lumbar spine decompression surgeries, after the mid-line decompression extending up to half of the facet joints, a further undercutting of the facet joints to 5–6mm is therefore required to completely decompress the nerve root in the foramen. The more coronal orientation of the facet joint at L5/S1 conforms better stability than that at L3/4level. Therefore, stabilisation of the spine should be considered if more than 2cm of the posterior elements are removed from midline at L3/4 level.

Introduction: Spinous process osteotomy (SPO) and multiple laminotomy can be used for multi-level lumbar decompression. We conducted an experimental study to compare the effects of these two methods on spinal kinetics.

Method: Ten fresh calf spines (L2- sacrum) were mounted in dental stone and segmental motion of L3 relative to L5 was assessed using an electromagnetic 3-D motion detection system (FASTRAK, Polhemus, Colchester, VT, USA). Pure moments of 0, 2.5, 5, 7, and 10 Nm were used in flexion/extension, right/left lateral bending, and right/left axial rotation. The moments were generated by applying two equal and opposite forces (weights) to the perimeter of a plastic circular disc, which was fixed to the superior end plate of L3 by three screws. In five spines decompression was performed at L3/4 and 4/5 using standard laminotomy technique. Decompression using SPO was done at L3–5 through a unilateral approach in the rest. Segmental mobility between the two methods was compared using the Mann-Whitney test.

Results: Mean range of motion in the specimens before intervention was-lateral bending (32.70 ± 7.6 SD), rotation (13.10 ± 4.8 SD), flexion/extension (19.30 ± 7.1 SD). There was statistically significant difference between mean increase in lateral bending after SPO to that following laminotomy (4.00 ± 1.5 SD vs 0.60 ± 1.6 SD; p=0.008). Mean increase in flexion- extension after SPO was not significantly different from that after laminotomy (4.50 ± 1.1 SD vs 3.90 ± 3.8 SD; p= 0.75). There was no difference in the mean increase in axial rotation after SPO compared to that following laminotomy (7.90 ± 3.6 SD vs 6.80 ± 5.0 SD; p= 0.75).

Conclusions: Both laminotomy and SPO produced increased range of motion in a calf spine model. SPO produced significant increase in lateral bending although its clinical significance is unknown.

Ethics approval: none

Interest Statement: Local grant (Research Fund, Centre for Spinal Studies, Robert Jones and Agnes Hunt Hospital, UK

In a prospective observational study we compared the two-year outcome of lumbar fusion by a simple technique using translaminar screws (n = 57) with a more extensive method using transforaminal lumbar interbody fusion and pedicular screw fixation (n = 63) in consecutive patients with degenerative disease of the lumbar spine. Outcome was assessed using the validated multidimensional Core Outcome Measures Index. Blood loss and operating time were significantly lower in the translaminar screw group (p < 0.01). The complication rates were similar in each group (2% to 4%). In all, 91% of the patients returned their questionnaire at two-years. The groups did not differ in Core Outcome Measures Index score reduction, 3.6 (sd 2.5) (translaminar screws) vs 4.0 (sd 2.8) (transforaminal lumbar interbody fusion) (p = 0.39); ‘good’ global outcomes, 78% (translaminar screws) vs 78% (transforaminal lumbar interbody fusion) (p = 0.99) or satisfaction with treatment, 82% (translaminar screws) vs 86% (transforaminal lumbar interbody fusion) (p = 0.52).

The two fusion techniques differed markedly in their extent and the cost of the implants, but were associated with almost identical patient-orientated outcomes.

Extensive three-point stabilisation is not always required to achieve satisfactory patient-orientated results at two years.

Aim: To evaluate morbidity and outcome associated with lumbar spine decompression for central spinal stenosis in the elderly compared with younger age groups.

Patients & Methods: Case notes review of patients with symptomatic and MRI proven central lumber canal stenosis, under the care of a single surgeon. The study population was 3 age groups: patients < 60 year of age (Group 1, n=19), patients between 61 and 79 years(Group 2, n=54), and > age of 80 years (Group 3, n=15).

The number of levels decompressed & grade of surgeon were noted.

Outcome data: Length of operation & hospital stay, blood loss, and intra and post operative complications. Subjective variables: Pain (VAS), walking distance, Oswestry Disability score (ODI) and patient satisfaction scores.

Results: The duration of operation (p< 0.05), and intra-operative complication rate (p< 0.025) was dependent on the seniority of the surgeon.

There was a statistically significant improvement in VAS score for leg pain (p< 0.05) and back pain (p< 0.05) after surgery for each group. The average walking distance improved by factor 5 in group 1 and 2 and by factor 2.5 in group 3 (p< 0.05)

Conclusions: Surgery for neurogenic claudication in the octogenarian is associated with a higher complication rate. The outcomes in this patient group is however comparable to younger patients.

A clinical retrospective study was conducted. Results of isolated decompression for degenerative lumbar stenosis was compared with the outcome in patients who underwent decompression-stabilisation.

From January 1992 to December 2002, 127 patients (average age 65.5) with lumbar degenerative stenosis surgically treated were studied. In all patients the Roy-Camille technique was used for decompression; in 41 patients decompression and posterior stabilisation procedures were carried out. Average follow-up was 6 years (range 2–11 years).

The outcomes, evaluated according to Lassale classification, were satisfactory in 81% of the decompressed group while improved to 88% in the stabilised–decompressed group. Three patients of the first group required stabilisation for intractable low back pain (one patient) and lumboradicular symptoms (two patients), while problems related to the device (one hardware failure) and two instances of adjacent segmental instability were seen in the second group.

Decompression alone is associated with an increased rate of residual low back pain (one patient in this cohort required fusion). The decompression–stabilisation procedure reduces the incidence of low back pain but is associated with other complications such as significant blood loss, possible wound infections, urinary tract infections (due to increased surgical time), device failures, root impingement and late adjacent segmental pathologies.

The Roy Camille technique is effective for achieving adequate decompression. The surgeon should always be aware of patients who might require fusion. The instrumented stabilisation should be reserved for patients with chronic low back pain and evident instability, degenerative spondylolisthesis and spine deformities such as scoliosis or kyphosis.