Introduction

Local recurrence of tumours along the biopsy tract is a known complication of percutaneous closed needle biopsy. Correct surgical management requires preoperative identification and excision of the biopsy tract at time of surgery. These tracts become increasingly difficult to identify with time, leading to risk of inadequate excision of the biopsy tract and recurrence of the tumour at the biopsy site.

Background

One of the basic principles in the primary survey of a trauma patient is immobilisation of the cervical spine till cleared of any injury. Lateral cervical spine radiograph is the gold standard initial radiographic assessment. More than often additional radiographs like the Swimmer's view are necessary for adequate visualisation of the cervical spine. How good is the Swimmer's view in visualisation of the cervical spine after an inadequate lateral cervical spine radiograph?

Aim: To assess the kinematic changes that occur within the lumbar spine 2 years following insertion of the Dynesys Spinal stabilisation implant.

Materials and Methods: Twenty patients who were treated with Dynesys surgical stabilisation for dominant lower back pain underwent positional MRI scanning before and two years following surgery.

The patients were divided into two groups, A and B. The first, Group A, in which only Dynesys was used and the second, Group B, in which Dynesys was used adjacent to one or more fused segments.

Results: The results of the pMRI measurements showed that the range of movement (ROM) of the L1/S1 angle in Group A reduced by 11.8o{pre-op=37.9o, postop=26.1o(p=0.085)} while in Group-B reduced by 12.3o {pre-op=37.8o, postop=25.5o(p=0.017)}.

The ROM of the end plate angle at the instrumented segments in Group A reduced from 5.72^o to 1.44^o{difference 4.28^o(p=0.005)} and in Group B reduced from 6.00^o to 2.17^o,{difference 3.83^o(p=0.001)}.

The ROM of the end plate angle at the level above instrumentation in Group A reduced from 8.2^o to 5.1^o {reduction 3.1^o(p=0.085)}, while in group-B increased from 7.3^o to 7.5^o, a difference of 0.2^o (p=0.877).

The mean anterior disc height in Group A reduced by 2.1mm (p< 0.001) from 9.59mm to 7.44mm. The posterior disc height also reduced from 6.56mm to 6.26mm, a difference of 0.3mm, (p=0.434). In Group B, the anterior disc height reduced by 1.98mm (pre-op=9.04mm, post-op= 7.06mm, p=0.001) and the posterior height by 0.35mm (pre-op 6.14mm to post op 5.79mm, p=0.443)

Discussion: This study shows that the Dynesys stabilisation system allows some movement at the operated segment two years following surgery. The study also confirms that the adjacent segment hypermobility often seen following spinal fusion surgery is eliminated.

Aim: To assess the kinematic changes that occur within the lumbar spine 2 years following insertion of the Dynesys Spinal stabilisation implant.

Materials and Methods: Twenty patients who were treated with Dynesys surgical stabilisation for dominant lower back pain underwent positional MRI scanning before and two years following surgery.

The patients were divided into two groups, A and B. The first, Group A, in which only Dynesys was used and the second, Group B, in which Dynesys was used adjacent to one or more fused segments.

Results: The results of the pMRI measurements showed that the range of movement (ROM) of the L1/S1 angle in Group A reduced by 11.8o{pre-op=37.9o, postop=26.1o(p=0.085)} while in Group-B reduced by 12.3o {pre-op=37.8o, postop=25.5o(p=0.017)}.

The ROM of the end plate angle at the instrumented segments in Group A reduced from 5.72^o to 1.44^o{difference 4.28^o(p=0.005)} and in Group B reduced from 6.00^o to 2.17^o,{difference 3.83^o(p=0.001)}.

The ROM of the end plate angle at the level above instrumentation in Group A reduced from 8.2^o to 5.1^o {reduction 3.1^o(p=0.085)}, while in group-B increased from 7.3^o to 7.5^o, a difference of 0.2^o (p=0.877).

The mean anterior disc height in Group A reduced by 2.1mm (p< 0.001) from 9.59mm to 7.44mm. The posterior disc height also reduced from 6.56mm to 6.26mm, a difference of 0.3mm, (p=0.434). In Group B, the anterior disc height reduced by 1.98mm (pre-op=9.04mm, post-op= 7.06mm, p=0.001) and the posterior height by 0.35mm (pre-op 6.14mm to post op 5.79mm, p=0.443)

Discussion: This study shows that the Dynesys stabilisation system allows some movement at the operated segment two years following surgery. The study also confirms that the adjacent segment hypermobility often seen following spinal fusion surgery is eliminated.

Purpose Of The Study: This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device.

Material-Method-Results: All the 25 patients, with chronic back pain, had discography preoperatively a positional MRI scans pre-op and nine months postoperatively in different postures.

The patients were divided into two groups. The Group-A with 14 patients in which only Dynesys was used and Group-B with 11 patients in which Dynesys was combined with fused levels.

The operated levels were 51, 13 of which were fused. The results showed that the mean range of movement of the lumbosacral angle reduced by 10.28° (Preop=39.21°, Postop=28.93°) (p=0.016) in group-A. In group-B it reduced by 13.73° (Preop=36.18°, Postop=22.45°) (p=0.02).

The range of movement of the end plate angle at the instrumented segments in group-A reduced by 2.96° (Preop=5.56°, Postop=2.60°) (p=0.016) while in group-Bit reduced by 4.23° (Preop=6.69°, Postop=2.46°)(p=0.008).

The mean range of movement of the end plate angle at adjacent level in group-A reduced by 1.58° (Preop=8.7°, Postop=7.21°)(p=0.427) while in group-B it increased by 1.73° (Preop=6.91°, Postop=8.64°) (p=0.149)

The mean anterior disc height in group-A reduced by 1.18mm (Preop=10.05mm, Postop=8.87mm) (p< 0.005), and the posterior one was increased by 0.6mm (Preop=6.51mm, Postop=8.87mm) (p=0.013). In group-B, the anterior disc height was reduced by 1.11mm (Preop= 10.44mm, Postop=9.33mm) (p=0.049) and the posterior one by 0.16mm (Preop=6.98mm Postop=6.82mm) (p=0.714)

Conclusion: Dynesys stabilizing system allows movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the more the anterior annulus than to distract the posterior.

Introduction The Dynesys device uses transpedicular screws linked by a cord and spacers. It is claimed that the advantage is that it allows some motion, in all directions, in the operative levels. In vitro laboratory biomechanical studies show that the movement permitted is similar to rigid fusions.

This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device.

Material-method In our study 20 patients with dominant low back pain, with or without leg pain, were treated with Dynesys system. Stress discography was made to evaluate the symptomatic level

All had a positional MRI preoperatively and nine months post-operatively in flexion-extension-lateral bending.

The patients were divided in to two groups:

Group(A) with 8 patients in which Dynesys was used with fusion (disc-height< 40 %)

Group(B) with 12 patients was the Dynesys-only group (disc-height=40–90%).

Results The operated levels were 42, 10 of those were fused levels. The results showed that there was a statistically significant difference in flexion-extension range of movement of the whole lumbar spine (mean= −13.45)(p< 0.005), but it wasn’t significant in the level above (mean=0.056)(p=0.972) and at a single instrumented segment was (mean=−4.06°)(p< 0.05)

The changes in the anterior disc height was (mean= −1.18)(p< 0.05) and to the posterior (mean=0.37)(p=0.134). In bending were (mean=−0.87°)(p=0.18) for left and (mean=−0.24°)(p=0.75) for the right

Discussion This study shows that in the Dynesys stabilizing system allows small range of movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the anterior annulus

Study Design: A prospective randomised controlled trial with blind radiological assessment.

Objective: To assess the radiological outcome of instrumented posterolateral lumbar fusion in a prospective randomised study comparing the use of allograft (fresh frozen human femoral head) to autologous bone (from the posterior iliac crest) using a validated method.

Methods: Sixty-nine patients having instrumented postero-lateral fusion using the Steffee plate were randomised to one of two groups, to receive either allograft bone or autologous bone. The same surgeon using the same surgical technique performed or supervised all cases. The radiological results of the two groups were assessed as well as the quality of fusion.

Outcome measures: The radiographs were assessed for fusion or non-fusion by three independent observers using the same criteria, and a second time by one of the observers. The Kappa scores for the inter-observer and intra-observer agreement were calculated. Some of these patients had fusion status verified by the gold standard of surgical exploration and the sensitivity and specificity calculated. The clinical outcome is the subject of a different paper.

Results: Both the inter-observer and intra-observer kappa scores (k) were 100%. The sensitivity of the method was 87.9% and the specificity was 100%. Thirty-seven patients received allograft and 32 patients received autograft. There was no significant difference in the fusion rate, or the quality and quantity of the graft between the groups.

Conclusions: There is no difference in the fusion rates comparing the use of autograft and allograft for postero-lateral instrumented lumbar fusion.

Introduction The Dynesys® stabilisation system (Zimmer Spine) uses transpedicular screws linked by a cord and spacers; the advantage claimed is that it allows some motion, in all directions, in the operated levels. In vitro laboratory biomechanical studies show that the movement permitted is similar to rigid fixation systems.

This study measures the changes in the lumbar spine in different postures, pre- and after insertion of the device. Methods In our study 25 patients with dominant low back pain, with or without leg pain, were treated with Dynesys system, 14 females and 11 males with mean age 43.5 yrs. Discography was done to evaluate the symptomatic painful level. All patients had a positional magnetic resonance imaging (pMRI) scans preoperatively and nine months post-operatively in standing; sitting flexion and extension, and left and right bending postures. The patients were initially divided into two groups. The first (Group A) with 14 patients in which only Dynesys was used (disc height 40–90%) and the second (group B) with 11 patients in which Dynesys was used with fusion (disc height < 40 %).

Results The operated levels were 51, 13 of which were fused. The results of the pMRI measurements showed that the mean range of movement of the lumbosacral angle reduced by 10.3° from pre-op of 39.2° to postop. of 28.9° (p= 0.016) in group A while in group B it reduced by 13.7° from 36.2° preop. to 22.5° postoperatively (p= 0.02).

The range of movement of the end plate angle at the instrumented segments in group A reduced from 5.6° preoperatively to 2.6° with a difference of 3.0° (p=0.016) while in group B it reduced from 6.7° to 2.5° postoperatively with a difference of 4.2°(p=0.008). The range of movement of the end plate angle at adjacent level in group A changed from 8.8° preop. to 7.2° with a reduction of 1.6° (p=0.427) while in group B it increased from 6.9° to 8.6°, difference of 1.7° (p=0.149)

The mean anterior disc height in group A reduced by 1.2mm (p< 0.005) from 10.1mm to 8.9mm postoperatively, and the posterior one was increased from 6.5mm to 8.9mm with a difference of 0.6mm (p= 0.013). In group B the anterior disc height was reduced by 1.1mm (pre-op 10.4mm to post-op 9.3mm; p=0.049) and the posterior one by 0.16mm (pre-op 6.98mm to post-op 6.82mm; p=0.714)

Discussion This study shows that in the Dynesys stabilising system allows a small range of movement at the instrumented levels, with no significant increased mobility in the adjacent levels. Also the device acted to compress the anterior annulus more than to distract the posterior annulus.

To assess the radiological outcome of instrumented posterolateral lumbar fusion in a prospective randomised study comparing the use of allograft (fresh frozen human femoral head) to autologous bone (from the posterior iliac crest), using a validated method.

One hundred and twenty four radiographs of patients who had undergone instrumented posterolateral spinal fusion were assessed for fusion or non-fusion by three independent observers using the same criteria, and a second time by one of the observers. The Kappa scores for the inter-observer and intra-observer agreement were calculated. Thirty-three of these patients had fusion status verified by the gold randomised to one of two groups, to receive either allograft bone or autologous bone. The same surgeon using the same surgical technique performed or supervised all cases. The radiological results of the two groups were assessed as well as the quality of fusion.

Both the inter-observer and intra-observer kappa scores (k) were 100%. The sensitivity of the method was 87.9% and the specificity was 100%. Thirty-seven patients received allograft and 32 patients received autograft. There was no significant difference in the fusion rate, or the quality and quantity of the graft between the groups.

There is no difference in the fusion rates comparing the use of autograft and allograft for posterolateral instrumented lumbar fusion.