The rate of subsidence for lumbar fusion surgery is variable from 7- 89%. Subsidance can affect the outcome of surgery by compramising alignment, foraminal height and stability. Modic changes have been shown to affect the stiffness and strength of the vertebral end plate and shown to affect both fusion rates and clinical outcome. Ongoing laboratory investigations into the material properties of the degenerate lumbar spine show modic changes affect the end plate and trabecular bone mechanics. This study aims to bridge this basic science research into clinical practice. A retrospective analysis of all patients in two tertiary spinal centres who have undergone lumbar interbody fusion with the implantation of a ‘cage’ over the past 6 years were analysed by two independent spinal surgeons. Pre-operative MRI findings were correlated with post-operative interbody cage subsidence after 1 year.Background
Methods
This study aims to establish the micro-structure of the vertebral endplate and its interface with the adjacent bone and disc in fresh, unstained tissue so that the structure can be related to normal and pathological function. The endplate is key in both the mechanics, anchoring and nutrition of the disc. Understanding the detailed structure of the normal and pathological endplate is important for understanding how it achieves its functions. Advancements in imaging technology continually allow for greater understanding of biological structures. The development of two-photon fluorescence (TPF) combined with second harmonic generation (SHG), allows for the imaging of relatively thick, fresh samples without the need for staining.Purpose of study
Background
Polyether ether ketone (PEEK) has been increasingly employed as biomaterials for trauma, orthopeadic, and spinal implants. However, concern has been raised about the inertness of PEEK which limits bone integration. In this study, we have coated PEEK with a functional material seeking to promote osteogenic differentiation of human mesenchymal stem cells (hMSC). We have used spray drying to coat poly(ethyl acrylate) (PEA) as a coating on PEEK. This technique is simple, allows a range of controlled coating thicknesses (from hundred nm to a few um), cost effective and easily translatable to scaffolds or implant surfaces for existing or new orthopaedic applications. PEA induces the organisation of fibronectin (FN) into nanonetworks upon simple adsorption from protein solutions. These FN nanonetworks on PEA represent a microenvironment for efficient growth factor binding and presentation in very low but effective doses. In this study we show cell adhesion and stem cell differentiation towards an osteogenic lineages when bone morphogenetic protein 2 (BMP2) was adsorbed on these engineered PEEK/PEA/FN microenvironments in very low doses. Overall, the developed functional coatings on PEEK has the potential to allow the translation of this material into orthopaedic applications.
To study the relationship between Zygoapophysial Joint Tropism and pathologic fractures affecting lumbar and thoracic vertebrae in elderly patients. The sagittal plane orientation of the Zygoapophysial joints (facets or ZAJ) of 324 vertebrae of 63 patients were measured on MRI scans, stratified into lumbar and thoracic, fractured and non-fractured, and then classified according to the presence of tropism. The correlation between tropism and fractures, demographics pertaining to age, spinal level, and morbidity were studied.Purpose
Methods
Lumbar spine foraminal stenosis has previously been defined by the foraminal and posterior disc height. We performed a study to determine whether residual clinically significant foraminal stenosis correlates with foraminal dimensions and peri-neural fat signal loss in a group of patients with leg pain undergoing surgery for lateral recess stenosis. We retrospectively studied the pre-operative para-sagittal MRI slices of 57 patients undergoing lumbar decompression and measured pre- and post-operative VAS as a primary outcome measure to evaluate surgical success. We performed a linear regression analysis comparing change in VAS score, 1 year VAS and percentage change in VAS with foraminal height and width and found no significant correlation (R2 <0.2 for all correlations). We identified a sub-group of 16 patients with absent perineural foraminal fat signal with a significantly increased probability of post-operative VAS>2 compared to patients with present fat signal (p=0.0001) who all had foraminal height <10mm. In conclusion, we were unable to define dimensional foraminal parameters for clinically significant foraminal stenosis on para-sagittal MRI. Obliteration of perineural fat was associated with worse outcome and post-operative leg pain. The aetiology of foraminal stenosis is multi-factorial and more detailed imaging of the foramen is required. We recommend that coronal and fine para-sagittal MRI slices are analysed to evaluate patients with central and lateral recess stenosis for co-existing foraminal stenosis.
To assess the effectiveness of dynamic stabilisation as a treatment for discogenic pain compared to standard treatment of interbody fusion. All patients were referred for a 2 year back-pain management programme. Patients with continued pain following conservative treatment underwent discography & MRI. Patients with painful degenerate discs on the above investigations were selected. Patients underwent interbody fusion (PLIF/TLIF) or dynamic stabilisation. Mean follow-up was 24 months with a minimum follow-up of 12 months. All patients had pre-operative ODI and VAS scores. Patients were then sent further questionnaires at 6 month intervals. The mean improvement in ODI following dynamic stabilisation was 20% (-20% → 56%), the mean improvement in the pain score was 2.4 (0→8). The mean improvement in ODI following interbody fusion was 11% (-14%→48%), the mean improvement in the pain score was 2.6 (-4→9). 10 patients in the dynamic stabilisation group had a greater than 20% improvement in ODI, 7 patients in the interbody fusion group had similar results. The above results demonstrate that dynamic stabilisation is at least as effective at treating discogenic pain as interbody fusion. The results however do question the validity of either interbody fusion (PLIF/TLIF) or dynamic stabilisation in the management of discogenic pain.
Previous studies have shown improved outcome following surgery for spinal cord compression due to metastatic disease. Further papers have shown that many patients with metastatic disease are not referred for orthopaedic opinion. The aims of this paper are to study the survival and morbidity of patients with spinal metastatic disease who receive radiotherapy. Do patients develop instability and progressive neurological compromise? Can we predict which patients will benefit from surgery? Retrospective review of patients receiving radiotherapy for pain relief or cord compression as a result of metastatic disease. Patients were scored with regards to Tomita and Tokuhashi, survival and for deterioration in neurology or spinal instability. 94 patients reviewed. All patients were followed up for a minimum of 1 year or until deceased. Majority of patients had a primary diagnosis of lung, prostate or breast carcinoma. Mean Tomita score of 6, Tokuhashi score 7, and mean survival following radiotherapy of 8 months. 11:94 patients referred for surgical opinion. Poor correlation with Tomita scores (-0.25) & Tokuhashi scores (0.24) to predict survival. Four patients developed progressive neurology on follow-up. One patient developed spinal instability. The remainder of the patients did not deteriorate in neurology and did not develop spinal instability. All patients with normal neurology at time of radiotherapy did not develop spinal cord compression or cauda equina at a later date. This study suggests that the vast majority of patients with spinal metastatic disease do not progress to spinal instability or cord compression, and that prophylactic surgery would not be of benefit. The predictive scoring systems remain unreliable making it difficult to select those patients who would benefit. The referral rate to spinal surgeons remains low as few patients under the care of the oncologists develop spinal complications.
Following the publication of our original survey in 2000 (Eur. Sp. J. 11(6):515-8 2002) we have sought to re-evaluate the perceptions and attitudes towards spinal surgery of the current UK orthopaedic Specialist Registrars (SpRs), and to identify factors influencing an interest in spinal surgery. At that time 175 orthopaedic spinal surgeons in the UK needed to increase by 25% to satisfy parity with other European countries. A postal questionnaire was sent to all 917 SpRs. The questionnaire sought to identify perceptions in spinal surgery, levels of current training and practice, and intentions to pursue a career in spinal surgery.Introduction
Methods
This study investigates the effect of somatisation on results of lumbar surgery. Pre- and post-operative data of all primary discectomies and posterior lumbar decompressions were prospectively collected. Pain using the Visual Analogue Score (VAS) and disability using the Oswestry Disability Index (ODI) were measured. Psychological assessment used the Distress Risk Assessment Method (DRAM). Follow-up was at 1 year.Introduction
Methods
To assess the effectiveness of dynamic stabilisation as a treatment for discogenic pain compared to standard treatment of interbody fusion. Study Design & Subjects All patients were referred for a 2 year back-pain management programme. Patients with continued pain following conservative treatment underwent discography & MRI. Patients with painful degenerate discs on the above investigations were selected. Patients underwent interbody fusion (PLIF/TLIF) or dynamic stabilisation. Mean follow-up was 24 months with a minimum follow-up of 12 months. All patients had pre-operative ODI and VAS scores. Patients were then sent further questionnaires at 6 month intervals.Objective
Outcome Measures
The recent NICE guidelines on management of osteoarthritis outline weight loss as first line treatment in degenerative joint disease in the obese. There is little data surrounding the effects of obesity on the outcomes in spinal surgical interventions. Intervertebral discectomy is one treatment for prolapse of a lumbar vertebral disc. We aim to investigate the effect of obesity on outcomes for discectomy. Demographic details including age, sex, weight and BMI were recording with a pre-operative Oswestry Disability Index (ODI). The fat thickness was measured at L5/S1 using calibrated MRI scans. Outcome measures included complications, length of surgery and change in ODI at 1 year following surgery. Obesity was defined as a body mass index of over 30. The units Serial patients undergoing discectomy were recruited into the study. Patients with bony decompression, instrumentation, revision surgery or multilevel disease were excluded. Fifty patients with a single level uncomplicated disc prolapse were entered into the study. Sixteen patients had a BMI over 30 and so were obese, whilst 34 had a BMI of less than 30. The mean pre-operative ODI was 46.5 in the obese group and 52 in the normal group this difference was not significant (p>
0.05). The mean post operative ODI was statistically improved in the high BMI group at 28 (18.5 point improvement) and 25.2 (29.1 point improvement) in the normal group. The ODI improvement was significantly better in the low BMI group (p=0.036). There was no significant difference in operative time (p=0.24). Only a single patient had a complication (dural leak), so no valid comparison could be made. The outcomes of spinal surgery in the obese are mixed. We found no increase in the complication rate or intra-operative time associated with an increased BMI. However, the improvement in ODI was significantly better in the normal BMI group.
The ‘disc’ group was significantly younger than ‘degenerative’ group (49.4 yrs vs. 58.4 yrs; p=0.004). There were significant improvements in low back pain (LBP), leg pain (LP), and ODI at 2 months in all patients. At 5 years the disc group did better with both leg and back pain; whilst there was only a significant reduction in leg pain in the degenerative group. Over 90% (n=56) of patients had no operative intervention; a subgroup of 8 had further injections. Within the degenerative group, ODI and VAS deteriorate early on indicating that a second injection option in this group may be worthwhile.
Approximately 5 – 10% of all bone fractures are associated with impaired healing. It is thought that regenerative medicine has the potential to improve on existing treatments for non-union fractures, and the European market for such treatments is projected to reach £2.2 billion in 2010. The use of scaffolds for the delivery of both growth factors and human Marrow Stromal Cells (hMSCs) is thought to be a promising approach. It may be desirable to promote proliferation and chemotaxis of hMSCs at the defect site shortly after implantation, and differentiation in the longer term. This is likely to require a dual delivery system, capable of releasing multiple drugs with different release profiles. Our aim has been to develop a polymer scaffold capable of releasing bioactive molecules that are able to direct the differentiation of primary hMSCs down the osteoblastic lineage. We have examined two mutually compatible drug delivery systems: collagen coating for short term release, and polymer encapsulation for longer term release. Polymer scaffolds were manufactured and coated with Type I Collagen containing BMP-7. hMSCs from three different patient sources were exposed to the scaffolds for 14 days. The cells were then histochemically stained for Alkaline Phosphatase (ALP) and photographed. The areas of ALP staining were then normalised against the total cell count. Normalised ALP expression was increased compared to the controls for three different patients (‘110 ± 39% SE, n=6, p=0.005’, ‘540 ± 270% SE, n=6, p=0.001’, and ‘32 ± 17% SE, n=6’). Scaffolds were also manufactured either with 1,25 Vitamin D3 (another active compound) in a coating of Collagen, or encapsulated using proprietary methodologies. It was found that both treatments significantly increased normalised Alkaline Phosphatase expression within the 14d experimental period demonstrating release of the active 1,25 Vitamin D3 (’88 ± 37% SE, n=6, p=0.012’ and ‘100 ± 32% SE, n=6, p=0.012’ respectively). Our findings suggest that, subject to future testing and development, such bioactive scaffolds could form the basis for a dual drug delivery system, suitable for applications in bone regenerative medicine.
Previous studies have shown improved outcome following surgery for spinal cord compression due to metastatic disease. Further papers have shown that many patients with metastatic disease are not referred for orthopaedic opinion. The aims of this paper are to study the survival and morbidity of patients with spinal metastatic disease who receive radiotherapy. Do patients develop instability and progressive neurological compromise? Do patients require surgery or are the majority adequately treated by oncologists? Review of patients receiving radiotherapy for pain relief or cord compression as a result of metastatic disease. Patients were scored with regards to Tomita and Tokuhashi, survival and for deterioration in neurology or spinal instability. 94 patients reviewed. All patients were followed up for a minimum of 1 year or until deceased. Majority of patients had a primary diagnosis of lung, prostate or breast carcinoma. Mean Tomita score of 6, Tokuhashi score 7, and mean survival following radiotherapy of 8 months. 11:94 patients referred for surgical opinion. Four patients developed progressive neurology on follow-up. One patient developed spinal instability. The remainder of the patients did not deteriorate in neurology and did not develop spinal instability. All patients with normal neurology at time of radiotherapy did not develop spinal cord compression or cauda equina at a later date. This study suggests that the vast majority of patients with spinal metastatic disease do not progress to spinal instability or cord compression, and that prophylactic surgery would not be of benefit. The referral rate to spinal surgeons remains low as few patients under the care of the oncologists develop spinal complications.
All pre-operative parameters were significantly higher compared with the Normal group (back pain VAS 6.3 and 3.8; leg pain VAS 7 and 4.7; ODI 61 and 34.4 respectively). At 1 year follow-up, 23% of the somatising patients became psychologically Normal; 36% became At Risk; 11% became Distressed Depressed; and 30% remained Distressed Somatisers. The postoperative VAS for back and leg pain of the 11 patients who had become psychologically Normal was 3.4 (pre-op 6.8) and 3.2 (pre-op 6.6) respectively. In the 14 patients who remained Distressed Somatisers the corresponding figures were 5.6 (pre-op 7.8) and 6.7 (pre-op 7.0). The postoperative ODI of the 11 patients who had become psychologically Normal was 26.4 (pre-op 55.5). In the 14 patients who remained Distressed Somatisers the corresponding figures were 56.7 (pre-op 61.7). These differences are statistically significant.
All pre-operative parameters were significantly higher compared with the Normal group (back pain VAS 6.3 and 3.8; leg pain VAS 7 and 4.7; ODI 61 and 34.4 respectively). At 1 year follow-up, 23% of the somatising patients became psychologically Normal; 36% became At Risk; 11% became Distressed Depressed; and 30% remained Distressed Somatisers. The postoperative VAS for back and leg pain of the 11 patients who had become psychologically Normal was 3.4 (pre-op 6.8) and 3.2 (pre-op 6.6) respectively. In the 14 patients who remained Distressed Somatisers the corresponding figures were 5.6 (pre-op 7.8) and 6.7 (pre-op 7.0). The postoperative ODI of the 11 patients who had become psychologically Normal was 26.4 (pre-op 55.5). In the 14 patients who remained Distressed Somatisers the corresponding figures were 56.7 (pre-op 61.7). These differences are statistically significant.