Background. 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. Methods. 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. Results. A total of 108 Interbody cages were included. Comparison of demographics did not reveal and significant between group variations. Comparison made between those displaying no modic changes and those displaying any of the three modic change types revealed a significantly higher subsidence rate in those displaying modic changes (p=0.003). Subgroup analysis showed that Type 2 modic changes (n=27) had a significantly higher subsidence rate (p=0.002). Those displaying type 3 modic changes (n=7) did not have any incidents of subsidence. Conclusions. Type 2 modic changes are associated with a higher rate of Lumbar interbody cage subsidence in this study. Those displaying type 3 changes seem to be protected from interbody cage subsidence. No Conflict of Interest. Funding: Produced as part of a research grant from the Gwen Fish Trust and Action Arthritis

We carried out a prospective study to determine whether the addition of a recombinant human bone morphogenetic protein (rhBMP-2) to a machined allograft spacer would improve the rate of intervertebral body fusion in the spine. We studied 77 patients who were to undergo an interbody fusion with allograft and instrumentation. The first 36 patients received allograft with adjuvant rhBMP-2 (allograft/rhBMP-2 group), and the next 41, allograft and demineralised bone matrix (allograft/demineralised bone matrix group). Each patient was assessed clinically and radiologically both pre-operatively and at each follow-up visit using standard methods. Follow-up continued for two years. Every patient in the allograft/rhBMP-2 group had fused by six months. However, early graft lucency and significant (> 10%) subsidence were seen radiologically in 27 of 55 levels in this group. The mean graft height subsidence was 27% (13% to 42%) for anterior lumbar interbody fusion, 24% (13% to 40%) for transforaminal lumbar interbody fusion, and 53% (40% to 58%) for anterior cervical discectomy and fusion. Those who had undergone fusion using allograft and demineralised bone matrix lost only a mean of 4.6% (0% to 15%) of their graft height. Although a high rate of fusion (100%) was achieved with rhBMP-2, significant subsidence occurred in more than half of the levels (23 of 37) in the lumbar spine and 33% (6 of 18) in the cervical spine. A 98% fusion rate (62 of 63 levels) was achieved without rhBMP-2 and without the associated graft subsidence. Consequently, we no longer use rhBMP-2 with allograft in our practice if the allograft has to provide significant structural support

Aims. The aim of this study was to investigate the incidence and characteristics of instrumentation failure (IF) after total en bloc spondylectomy (TES), and to analyze risk factors for IF. Methods. The medical records from 136 patients (65 male, 71 female) with a mean age of 52.7 years (14 to 80) who underwent TES were retrospectively reviewed. The mean follow-up period was 101 months (36 to 232). Analyzed factors included incidence of IF, age, sex, BMI, history of chemotherapy or radiotherapy, tumour histology (primary or metastasis; benign or malignant), surgical approach (posterior or combined), tumour location (thoracic or lumbar; junctional or non-junctional), number of resected vertebrae (single or multilevel), anterior resection line (disc-to-disc or intravertebra), type of bone graft (autograft or frozen autograft), cage subsidence (CS), and local alignment (LA). A survival analysis of the instrumentation was performed, and relationships between IF and other factors were investigated using the Cox regression model. Results. A total of 44 patients (32.4%) developed IF at a median of 31 months (interquartile range 23 to 74) following TES. Most IFs were rod fractures preceded by a mean CS of 6.1 mm (2 to 18) and LA kyphotic enhancement of 10.8° (-1 to 36). IF-free survival rates were 75.8% at five years and 56.9% at ten years. The interval from TES to IF peaked at two to three years postoperatively and continued to occur over a period of time thereafter; the early IF-developing group had greater CS at one month postoperatively (CS1M) and more lumbar TES. CS1M ≥ 3 mm and sole use of frozen autografts were identified as independent risk factors for IF. Conclusion. IF is a common complication following TES. We have demonstrated that robust spinal reconstruction preventing CS, and high-quality bone grafting are necessary for successful reconstruction. Cite this article: Bone Joint J 2023;105-B(2):172–179

We evaluated the efficacy of anterior fusion alone compared with combined anterior and posterior fusion for the treatment of degenerative cervical kyphosis. Anterior fusion alone was undertaken in 15 patients (group A) and combined anterior and posterior fusion was carried out in a further 15 (group B). The degree and maintenance of the angle of correction, the incidence of graft subsidence, degeneration at adjacent levels and the rate of fusion were assessed radiologically and clinically and the rate of complications recorded. The mean angle of correction in group B was significantly higher than in group A (p = 0.0009). The mean visual analogue scale and the neck disability index in group B was better than in group A (p = 0.043, 0.0006). The mean operation time and the blood loss in B were greater than in group A (p < 0.0001, 0.037). Pseudarthrosis, subsidence of the cage, and problems related to the hardware were more prevalent in group A than in group B (p = 0.034, 0.025, 0.013). Although the combined procedure resulted in a longer operating time and greater blood loss than with anterior fusion alone, our results suggest that for the treatment of degenerative cervical kyphosis the combined approach leads to better maintenance of sagittal alignment, a higher rate of fusion, a lower incidence of complications and a better clinical outcome

We do know that the use of stand-alone cage with no plate is prone to subsidence and segmental kyphosis. Cage and plate construct are prone to adjacent level ossification. Zero P (Synthes, UK) cage combines the functionality of spacer and anterior plate. Radiological evaluation of subsidence of cervical spine after anterior cervical interbody fusion using Zero P cage system. Method: Retrospective review of radiographic records of patients undergoing surgery between June 2008- Oct 2009. We evaluated lateral cervical standing radiographs before, after, 6 weeks, 3, 6 months of surgery. We measured subsidence (using Total Intervertebral Height (TIH). All measurements were done using Web 1000 (Impax Agfa). Two level was treated as single segment. Subsidence > 3mm was considered significant. 20 patients (11 male: 9 female) with median age of 51 yrs (40-65) underwent one (n=10) or two level (n= 10) cervical fusion. Immediately post-op there was increase in TIH in one and two level group by 1.74mm (1.61 and 4.25mm (1.48 respectively, which at 6 months reduced to 1.05mm (0.24 (p< 0.003) and 1.32mm (1.29 (p< 0.085) at 6 months respectively. Subsidence was seen in all cases and was rapid in first 3 months and then tailed off. It was significant (> 3mm) only in 2/20 (2%) patients at 6 months. Early results indicate that spine alignment is maintained radiologically with no associated complications as screw loosening, cage extrusion etc

Aims

The optimal procedure for the treatment of ossification of the posterior longitudinal ligament (OPLL) remains controversial. The aim of this study was to compare the outcome of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) with posterior laminectomy and fusion with bone graft and internal fixation (PTLF) for the surgical management of patients with this condition.

Aims

Surgical approaches to cervical ossification of the posterior longitudinal ligament (OPLL) remain controversial. The purpose of the present study was to analyze and compare the long-term neurological recovery following anterior decompression with fusion (ADF) and posterior laminectomy and fusion with bone graft and internal fixation (PLF) based on > ten-year follow-up outcomes in a single centre.

We present data relating to the Bryan disc arthroplasty for the treatment of cervical spondylosis in 46 patients. Patients with either radiculopathy or myelopathy had a cervical discectomy followed by implantation of a cervical disc prosthesis. Patients were reviewed at six weeks, six months and one year and assessment included three outcome measures, a visual analogue scale (VAS), the short form 36 (SF-36) and the neck disability index (NDI). The results were categorised according to a modification of Odom’s criteria. Radiological evaluation, by an independent radiologist, sought evidence of movement, stability and subsidence of the prosthesis. A highly significant difference was found for all three outcome measurements, comparing the pre-operative with the post-operative values: VAS (Z = 6.42, p < 0.0001), SF-36 (mental component) (Z = −5.02, p < 0.0001), SF-36 (physical component) (Z = −5.00, p < 0.0001) and NDI (Z = 7.03, p < 0.0001). The Bryan cervical disc prosthesis seems reliable and safe in the treatment of patients with cervical spondylosis

Aims

To evaluate the perioperative complications associated with total en bloc spondylectomy (TES) in patients with spinal tumours, based on the extent and level of tumour resection.

Aim. To assess the safety of Zero Profile Interbody fusion (Zero P) device in Anterior Cervical Decompression and fusion (ACDF) for degenerative cervical stenosis. Method. 89 consecutive patients treated with Zero P interbody device from September 2009 to September 2012 were included in this retrospective study. Inclusion criterion: degenerative cervical stenosis with myelopathy, persistent radiculopathy after at least 3 months of failed conservative management. Exclusion criterion: Paediatric population; patients with infection, metastatic disease and trauma. There were 39 females, 50 males with mean age of 55 (ranging from 24 to 84 years). 56 (64%) had surgery at 1 level, 31 (35%) at 2 levels, 1 (1%) at 3 levels. Total number of levels operated were 121. Common levels operated were C56 (62%) and C67 (47%). Majority were operated due to radicular symptoms, 56 (64%) had radicular symptoms, 28(31%) had myelopathy and 5 (5%) Myeloradiculopathy. Results. All had a minimum of 6 months follow up (maximum 2 years). No patient had cage subsidence or extrusion. 1 had superficial infection which settled with antibiotics, 10 (11%) had dysphagia which settled in 6 to12 weeks. Conclusions. Our study demonstrates that ACDF with Zero P can be considered a safe option in management of patients with cervical degenerative stenosis. We would will also recommend a prospective randomised study as a follow on to this retrospective study. Preoperative kyphosis or lordosis did not change the outcome or make the surgical technique any more difficult, hence this implant can also be used in these circumstances. Conflicts of interest: No conflicts of interest. Sources of funding: No funding obtained

The footplate in the current available TDR is flat without any allowance for endplate concavity in the sagittal plane. To assess the morphology of the endplates of the lower lumbosacral in the sagittal plane, and to identify the frequently occurring shape patterns of the end plates at each level. Retrospective Study. 200 consecutive magnetic reasonance imaging (MRI) scans of patients between the age of 30 and 60 years were analysed. In each endplate, the anteroposterior width, the height of concavity of the endplate, and the distance of the summit from the anterior vertebral body margin were noted. The shape of the endplate was noted as oblong (o) if the curve was uniform starting from the anterior margin and finishing at the posterior margin, eccentric (e) if the curve started after a flat portion at the anterior border and then curving backwards, and flat (f) if there is no curve in the sagittal plane. The shape of the end plate is mostly oblong at L3 IEP(59%), equally distributed between oblong and eccentric at L4 SEP (o=43.5%, e=46.5%), eccentric at L4 IEP (e=62.5%), eccentric at L5 SEP (e = 59.0%), eccentric at L5 IEP (e=94.0%), and flat at S1 SEP (f=82.5%). As there is a difference in the shape of the endplate at each level and they are not uniform, there is a need to focus on the sagittal shape of the footplate to avoid subsidence and mismatch of the footplate in cases of endplate concavity

Purpose of the study. To compare safety and efficacy of cervical disc replacement (CRD) in single and multilevel DDD. Patients were followed up at 1, 3, 6, 12 and 24 months. Methods. 249 patients were enrolled. 171 patients were treated at 1-level, 41 treated at 2 levels and 2 patients were treated at 3 levels. Implant was also used adjacent to a fusion with a cage in 35 patients. The diagnosis was cervical degenerative disc disease between C3 and C7 with symptomatic DH. Population was 106 male 143 female, average age 46 (25-71). Clinical assessment included VAS scores for arm and neck pain and Neck Disability Index (NDI). Range of motion (ROM) from flexion/extension lateral view were measured. Results. Of all NDI scores recorded, 86,50 % demonstrated at least 15 points improvement at two years follow up from pre-op scores. 85,1% of VAS arm Pain scores demonstrated an improvement by = 2 points from pre-op scores and 50,8% for VAS neck Pain scores. The breakdown by levels and adjacent to an interbody cage shown that 80% of reported NDI scores demonstrated at least a 15 point improvement post operatively for two level disc replacement. 82,4% demonstrated a greater than 2 points improvement in VAS arm pain and 53,3% for VAS neck pain. For patients that received both implant and an interbody cage, 72,7% demonstrated a greater than 2 point improvement in VAS arm pain and 41,7% for VAS neck pain. Three (1,8%) cases of subsidence and 4 cases of implant loosening/displacement due to inappropriate sizing were reported. Available radiographic findings show on average a ROM of 8,2 ° at 2 years and an overall change in cervical lordosis of 5° from pre-op. Conclusion. Clinical outcomes demonstrated a significant improvement for both the total population (n=249) and for the single level total disc replacement population (n=171). Given these outstanding results single and multilevel TDR with this implant can be considered to be safe. No significant difference was observed between single and multilevel TDR groups regarding clinical, functional and radiological results. Follow up for this series need however to be extended for up to 5 years at least. The role of this implant in multilevel cases as well as in cases to a fused level still need further evaluation although these preliminary results are encouraging

Aims

We compared the clinical and radiological outcomes of using a polyetheretherketone cage with (TiPEEK) and without a titanium coating (PEEK) for instrumented transforaminal lumbar interbody fusion (TLIF).

The presacral retroperitoneal approach for axial lumbar interbody fusion (presacral ALIF) is not widely reported, particularly with regard to the mid-term outcome. This prospective study describes the clinical outcomes, complications and rates of fusion at a follow-up of two years for 26 patients who underwent this minimally invasive technique along with further stabilisation using pedicle screws. The fusion was single-level at the L5-S1 spinal segment in 17 patients and two-level at L4–5 and L5-S1 in the other nine. The visual analogue scale for pain and Oswestry Disability Index scores were recorded pre-operatively and during the 24-month study period. The evaluation of fusion was by thin-cut CT scans at six and 12 months, and flexion-extension plain radiographs at six, 12 and 24 months. Significant reductions in pain and disability occurred as early as three weeks postoperatively and were maintained. Fusion was achieved in 22 of 24 patients (92%) at 12 months and in 23 patients (96%) at 24 months. One patient (4%) with a pseudarthrosis underwent successful revision by augmentation of the posterolateral fusion mass through a standard open midline approach.

There were no severe adverse events associated with presacral ALIF, which in this series demonstrated clinical outcomes and fusion rates comparable with those of reports of other methods of interbody fusion.

Fracture of a pedicle is a rare complication of spinal instrumentation using pedicular screws, but it can lead to instability and pain and may necessitate extension of the fusion. Osteosynthesis of the fractured pedicle by cerclage-wire fixation and augmentation of the screw fixation by vertebroplasty or temporary elongation of the fixation, allows stabilisation without sacrifice of the adjacent healthy segment. We describe three patients who developed a fracture of the pedicle in the most caudal instrumented vertebra early after lumbar spinal fusion.

During revision surgery the pedicles were reduced and secured by a soft cerclage wire bilaterally. Fusion was obtained at the site of the primary instrumentation and healing of the pedicles was achieved. Cerclage wiring of the fractured pedicle seems to be safe and avoids permanent extension of the fusion without the sacrifice of an otherwise healthy segment.

Between January 1990 and December 2000 we carried out 226 SB Charité III disc replacements for lumbar disc degeneration in 160 patients. They were reviewed at a mean follow-up of 79 months (31 to 161) to determine the clinical and radiological outcome. The clinical results were collected by an independent observer, who was not involved in patient selection, treatment or follow-up, using a combination of outcome measures, including the Oswestry Disability Index. Pain was recorded using a visual analogue score, and the most recent radiographs were reviewed.

Survival of the device was analysed by the Kaplan-Meier method and showed a cumulative survival of 35% at 156 months when radiological failure was taken as the endpoint. The mean improvement in the Oswestry disability index scores after disc replacement was 14% (6% to 21%) and the mean improvement in the pain score was 1.6 (0.46 to 2.73), both falling below the clinically significant threshold. Removal of the implant was required in 12 patients, four because of implant failure.

These poor results indicate that further use of this implant is not justified.

In a retrospective cohort study we compared the clinical outcome and complications, including dysphagia, following anterior cervical fusion for the treatment of cervical spondylosis using either a zero-profile (Zero-P; Synthes) implant or an anterior cervical plate and cage. A total of 83 patients underwent fusion using a Zero-P and 107 patients underwent fusion using a plate and cage. The mean follow-up was 18.6 months (sd 4.2) in the Zero-P group and 19.3 months (sd 4.1) in the plate and cage group. All patients in both groups had significant symptomatic and neurological improvement. There were no significant differences between the groups in the Neck Disability Index (NDI) and visual analogue scores at final follow-up. The cervical alignment improved in both groups. There was a higher incidence of dysphagia in the plate and cage group on the day after surgery and at two months post-operatively. All patients achieved fusion and no graft migration or nonunion was observed.

When compared with the traditional anterior cervical plate and cage, the Zero-P implant is a safe and convenient procedure giving good results in patients with symptomatic cervical spondylosis with a reduced incidence of dysphagia post-operatively.

Cite this article: Bone Joint J 2013;95-B:543–7.

Anterior debridement, grafting of the defect and posterior instrumentation as a single-stage procedure is a controversial method of managing pyogenic vertebral osteomyelitis. Between 1994 and 2005, 37 patients underwent this procedure at our hospital, of which two died and three had inadequate follow-up. The remaining 32 were reviewed for a mean of 36 months (12 to 66). Their mean age was 48 years (17 to 68). A significant pre-operative neurological deficit was present in 13 patients (41%). The mean duration of surgery was 285 minutes (240 to 360) and the mean blood loss was 900 ml (300 to 1600). Pyogenic organisms were isolated in 21 patients (66%). All patients began to mobilise on the second post-operative day. The mean hospital stay was 13.6 days (10 to 20). Appropriate antibiotics were administered for 10 to 12 weeks. Early wound infection occurred in four patients (12.5%), and late infection in two (6.3%).

At final follow-up, the infection had resolved in all patients, neurological recovery was seen in ten of 13 (76.9%) and interbody fusion had occurred in 30 (94%). The clinical outcome was excellent or good in 30 patients according to Macnab’s criteria.

This surgical protocol can be used to good effect in patients with pyogenic vertebral osteomyelitis when combined with appropriate antibiotic therapy.