This study reports the ten-year polyethylene liner wear rates, incidence of osteolysis, clinical outcomes and complications of a three-arm, multicentre randomised controlled trial comparing Cobalt-Chrome (CoCr) and Oxidised Zirconium (OxZr) femoral heads with ultra-high molecular weight polyethylene (UHMWPE) versus highly cross-linked polyethylene (XLPE) liners in total hip arthroplasty (THA). Patients undergoing THA from four institutions were prospectively randomised into three groups. Group A received a CoCr femoral head and XLPE liner; Group B received an OxZr femoral head and XLPE liner; and Group C received an OxZr femoral head and UHMWPE liner. Blinded observers recorded predefined outcomes in 262 study patients at regular intervals for ten years following THA. At ten years follow-up, increased linear wear rates were recorded in group C compared to group A (0.133 ± 0.21 mm/yr vs 0.031 ± 0.07 mm/yr respectively, p<0.001) and group B (0.133 ± 0.21 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p<0.001). Patients in group C were associated with increased risk of osteolysis and aseptic loosening requiring revision surgery compared with group A (7/133 vs 0/133 respectively, p=0.007) and group B (7/133 vs 0/135 respectively, p=0.007). There was a non-significant trend towards increased liner wear rates in group A compared to group B (0.031 ± 0.07 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p=0.128). All three groups were statistically comparable preoperatively and at ten years follow-up when measuring normalised Western Ontario and McMaster Universities Osteoarthritis Index(p=0.410), short-form-36 (p = 0.465 mental, p = 0.713 physical), and pain scale scores (p=0.451). The use of UHMWPE was associated with progressively increased annual liner wear rates after THA. At ten years follow-up, this translated to UHMWPE leading to an increased incidence of osteolysis and aseptic loosening requiring revision THA, compared with XLPE. Femoral heads composed of OxZr were associated with a non-significant trend towards reduced wear rates compared to CoCr, but this did not translate to any differences in osteolysis, functional outcomes, or revision surgery between the two treatments groups.
This study reports the ten-year outcomes of a three-arm, multicentre randomised controlled trial comparing Cobalt-Chrome (CoCr) and Oxidised Zirconium (OxZr) femoral heads with ultra-high molecular weight polyethylene (UHMWPE) versus highly cross-linked polyethylene (XLPE) liners in total hip arthroplasty (THA). Patients undergoing THA from four institutions were prospectively randomised into three groups. Group A received a CoCr femoral head and XLPE liner; Group B received an OxZr femoral head and XLPE liner; and Group C received an OxZr femoral head and UHMWPE liner. The outcomes of 262 study patients were analysed at ten years follow-up. At ten years, increased linear wear rates were recorded in group C compared to group A (0.133 ± 0.21 mm/yr vs 0.031 ± 0.07 mm/yr respectively, p<0.001) and group B (0.133 ± 0.21 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p<0.001). Patients in group C had increased risk of osteolysis and aseptic loosening requiring revision surgery compared with group A (7/133 vs 0/133 respectively, p=0.007) and group B (7/133 vs 0/135 respectively, p=0.007). There was a non- significant trend towards increased liner wear rates in group A compared to group B (0.031 ± 0.07 mm/yr vs 0.022 ± 0.05 mm/yr respectively, p=0.128). All three groups were statistically comparable preoperatively and at ten years follow-up from a clinical score perspective. The use of UHMWPE was associated with progressively increased annual liner wear rates. At ten years follow-up, this translated to an increased incidence of osteolysis and aseptic loosening requiring revision, compared with XLPE. Femoral heads composed of OxZr were associated with a non-significant trend towards reduced wear rates compared to CoCr, but this did not translate to any differences in osteolysis, functional outcomes, or revision surgery between the two treatments groups.
Bertolotti first described articulation of the L5 transverse process with the sacrum as a cause of back pain in 1917. Since then little attention has been payed to these atypical articulations despite their high reported incidence. Here we describe our early experience of surgical treatment and propose a validated CT based classification of lumbosacral segment abnormalities (LSSA). 400 lumbosacral CT scans were reviewed (NBT), a classification devised and incidence of abnormalities recorded. 40 patients were selected and 4 independent observers classified each scan. Case notes for all patients (C&V) who received steroid injections into or surgical excision of LSSAs were reviewed. Results as follows: 5 types of abnormality were identified. Type 0 - normal Type 1 - asymmetrical shortening of the iliolumbar ligament Type 2 - transverse process of L5 within 2mm of the sacrum Type 3 - diarthrodial joint (3A: no evidence of degeneration 3B: degenerative change) Type 4 - transverse process and sacrum have fused Type 5 - extends to L4 54.5% of patients had abnormalities. The kappa values for the intra-observer results were 0.69 to 0.88 and the inter-observer ratings gave a combined score of over 0.7 indicating substantial agreement. Our CT classification of LSSAs is both straight forward to use and repeatable. The incidence of these abnormalities is higher in our population of CT scans compared to previous published series using plain radiographs. All patients treated with surgical excision of established articulations (Type 3A or above) reported good or excellent outcomes following excision.
The study aim was to simulate oblique spinous process abutment (SPA) in cadaveric spines and determine how this affects coupled motion in the coronal plane. L4-S1 spinal segments from thirteen cadavers were loaded on a materials testing machine in pure compression at 1kN for 10 minutes. Reflective markers on the vertebral bodies were used to assess coronal motion using a motion analysis system. Oblique SPA was simulated by attaching moulded oblique aluminium strips to the L4 and L5 spinous processes. In each specimen, both a right- and left-sided SPA was simulated, in random order, and compression at 1kN was again applied. All tests were then repeated after endplate fracture. Coronal plane motion at baseline was compared with values following simulated SPA using Mann Whitney U-tests. Pre-fracture, SPA increased coronal motion by 0.28° and 0.34° on right and left sides respectively, compared to baseline, only the former was significant (P=0.03). Post-fracture, SPA decreased coronal motion by 0.36° and 0.46° on right and left sides respectively, only the latter was significant (P=0.03). Simulated oblique SPA in the intact spine initiated an increase in coronal motion during pure axial loading. These findings provide limited evidence that oblique SPA may be causative in DLS.
An often neglected component of sagittal balance in adolescent idiopathic scoliosis (AIS) is the cervical spine. The cervical spine is capable of compensating for large sagittal deformities by altering head position, but in doing so may give rise to symptoms when the extremes of cervical compensatory mechanisms are reached. This paper seeks to define whether AIS patients have a different cervical lordosis pre and post corrective surgery when compared to normal adolescents. A review of the literature was carried out in order to define normal cervical lordosis in adolescents. A retrospective analysis of 81 patients with a confirmed diagnosis of idiopathic scoliosis who had received corrective surgery was carried out, and pre and post op cervical lordosis of C1– C7 and C2– C7 were independently measured and recorded using full length sagittal spine radiographs. This data was compared to the 95% confidence interval (95% CI) of cervical lordosis in controls to show if AIS patients showed different cervical spine lordosis before or after corrective surgery. A literature search showed that normal cervical spine lordosis values are poorly described. However, some values have been published. One study (paper A) gives values of −16° (95%CI −12–20°) for male C2– C7 lordosis and −15° (95% CI −12.5–17.5°) for female C2– C7 adolescents. Another reference (paper B) gives values of −8.4 (95%CI −6.7–10.1°) for male and −1.9 (95%CI −0.5–3.3°) for female adolescents for the same C2– C7 measurements. Our values for male patients for pre op C2– C7 lordosis was −1.2 (95%CI −8.5–6.1°) and 9° (95%CI 2.9– 15.1°) for females. Post op values were 10.6° (95%CI 2.4–18.8°) for males and 8.3° (95%CI 4.8–11.8°) for females. The values of cervical lordosis in our series show that patients with AIS have a significantly different cervical lordosis when compared to normal values both pre and post deformity correction (p < 0.05). A complete understanding of how the cervical spine is positioned prior to surgery is critical, as flattening the thoracic spine during corrective surgery could give rise to cervical pain and sagittal imbalance if the ability of the cervical spine to compensate for the new spinal position is exceeded.
AIS is present in 3–5% of the general population. Large curves are associated with increased pain and reduced quality of life. However, no information is available on the impact of smaller curves, many of which do not reach secondary care. The objective of this project was to identify whether or not there is any hidden burden of disease associated with smaller spinal curves. The Avon Longitudinal Study of Parents and Children (ALSPAC) is a population-based birth cohort that recruited over 14,000 pregnant women from the Bristol area between 1991–1992 and has followed up their offspring regularly. At aged 15 presence or absence of spinal curvature ≥6degrees was identified using the validated DXA Scoliosis Measure in 5299 participants. At aged 18 a structured pain questionnaire was administered to 4083 participants. Chi-squared was used to investigate any association between presence of a spinal curve at aged 15 and self-reported pain at aged 18 years. Sensitivity analyses were performed by rerunning analyses after excluding those who were told at aged 13 they had a spinal curve (n=27), and using a higher spinal curve cut-off of ≥10degrees. Full data was available for 3184 participants. Of these, 56.8% were female, and 4.2% non-white reflecting the local population. 202 (6.3%) had a spinal curve ≥6degrees and 125 (3.9%) had a curve ≥10degrees. The mean curve size was 12degrees. 140/202 (69.3%) had single curves, and 57.4% of these were to the right. In total 46.3% of the 3184 participants reported aches and pains that lasted for a day or longer in the previous month, consistent with previous literature. 16.3% reported back pain. Those with spinal curves ≥6degrees were 42% more likely to report back pain than those without (OR 1.42, 95%CI 1.00 to 2.02, P=0.047). In addition, those with spinal curves had more days off school, were more likely to avoid activities that caused their pain, were more likely to think that something harmful is happening when they get the pain, and were more afraid of the pain than people without spinal curves (P<0.05). Sensitivity analyses did not change results. We present the first results from a population-based study of the impact of small spinal curves and identify an important hidden burden of disease. Our results highlight that small scoliotic curves that may not present to secondary care are nonetheless associated with increased pain, more days off school and avoidance of activities.
The prevalence of degenerative spondylolisthesis (DS) increases with age. With an ageing population there will be increasing demands for adult deformity surgery, with associated significant financial and complication costs. The prevalence of lytic spondylolisthesis (LS) is 6–8%. Our clinical observation is that it is extremely rare to see LS in the presence of DS and therefore the objective was to formally describe the prevalence of LS in combination with DS to assess the hypothesis that 6–8% of patients with DS should also have LS. If this is not the case it may further our understanding of the pathogenesis of DS, which could aid in future prevention or treatment. A retrospective review of erect lateral lumbar radiographs demonstrating lumbar spondylolisthesis was performed. Radiographs were identified and analysed on the hospital Synapse Picture Archiving and Communication System (PACS). Search criteria were radiographs requested by primary care and patients aged over 60. 101 patients with spondylolisthesis were identified. 89% were requested for back or leg pain. There were 89 patients with DS (69.7% women) and 12 with LS (83% men). The average age of DS and LS patient was 75 and 70 respectively (not significant). There were no cases found with both DS and LS. This was significantly different to the expected amount of 6% (p=0.03). The level of DS was at L3/4 in 11.2% (n=10), L4/5 in 79.8% (n=71) and L5/S1 in 16.9% (n=15). 2 levels were involved in 7 patients. 94.4% (n=84) demonstrated a Meyerding grade 1 slip and 5.6% (n=5) grade 2 slip. For LS the slipped level was at L5/S1 in all cases. 66.7% (n=8) had a grade 1 slip and 33.3% (n=4) a grade 2 slip. We found no cases of lytic spondylolisthesis in the presence of degenerative spondylolisthesis. We hypothesis that the presence of spondylolysis or lytic spondylolisthesis may be protective against development of degenerative spondylolisthesis. More work is needed to explore this further.
The Lenke Classification for adolescent idiopathic scoliosis (AIS) classifies curves as nonstructural if they reduce to less than 25° on bending radiographs. We aimed to establish whether there is a significant difference in curves assessed as structural/ nonstructural when comparing bending radiographs to forced traction radiographs. We undertook a retrospective database review of 100 consecutive AIS patients having undergone surgical correction by the 2 senior authors, together with radiographic review. Curves were classified according to the Lenke system including modifiers. Magnitude of the minor curves were compared on plain PA standing radiographs, bending radiographs and forced traction radiographs.Aim:
Methods:
To compare the degree of deformity correction achieved using cobalt chromium versus titanium alloy rods in patients with Adolescent Idiopathic Scoliosis. A retrospective comparison of two cohorts of patients with Adolescent Idiopathic Scoliosis treated with posterior segmental pedicle screw fixation using either Titanium or Cobalt Chromium rods. The radiographs of 50 patients treated before 2009 (Ti group) and 50 patients after 2009 (CoCr group) were reviewed for changes in: Main Coronal Curvature Sagittal Balance (C7 Plumb Line) Kyphosis (T5-12)Aim:
Method:
Deep infection following paediatric spinal deformity surgery is a serious complication, which can also result in increased length of stay and significant cost implications. Our objective was to reduce deep infection rates following spinal deformity surgery. All paediatric patients undergoing spinal deformity procedures between 2008 and 2010 (group 1) were prospectively followed up and deep infection rates recorded. In 2010, a review of infection rates necessitated a change in pre-operative, peri-operative, and post-operative practice. A scoliosis wound care pathway was implemented, which involved insertion of drains to protect wounds, strict dressing management performed by a Spinal Nurse Practitioner, and a telephone helpline for concerns about wound care and general peri-operative scoliosis care. The use of betadine wash and local antibiotic application intra-operatively were other measures instigated later in this period. All paediatric patients undergoing surgery between 2011 and 2012 (group 2) were then followed up and differences in infection rates between the two groups were analysed.Aim:
Method:
To determine if patients with coronal plane deformity in the lumbar spine have a higher grade of lumbar spine subtype compared to controls. This was a retrospective case/control study based on a review of radiological investigations in 250 patients aged over 40 years who had standing plain film lumbar radiographs with hips present. Measurements of lumbar coronal plane angle, lumbar lordosis, sacral slope, pelvic tilt and pelvic incidence were obtained. “Cases” with degenerative scoliosis (n=125) were defined as patients with a lumbar coronal plane angle of >10°. Lumbar spine subtype was categorised (1–4) using the Roussouly classification. Lumbar spine subtype was dichotomised into low (type 1,2) or high (type 3,4). Prevalence of lumbar spine subtype in cases versus controls was compared using the Chi squared test. Pelvic incidence was compared using an unpaired T-test. Predictors of lumbar coronal plane angle were identified using stepwise multiple regression. Significance was accepted at P<0.05.Aim:
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To compare the ability of fulcrum bend and traction radiographs to predict correction of AIS using pedicle screw only constructs and to compare the fulcrum bending correction index (FBCI) with a new measurement: the traction correction index (TCI). Retrospective radiographic analysis of eighty patients, average age 14 yrs, who underwent posterior correction of scoliosis using pedicle screw only construct. Analysis was carried out on the pre-op and immediate post-op PA radiographs and the pre-op fulcrum bend and traction radiographs. Correction rate, fulcrum flexibility, traction flexibility, FBCI and TCI was calculated.Aim:
Method:
Recent guidelines have been published by the Association of Neurophysiological Scientists / British Society for Clinical Neurophysiology (ANS/BSCN) regarding the use of intra-operative neurophysiological monitoring (IOM) during spinal deformity procedures. We present our unit's experience with IOM and the compliance with national guidelines. All patients undergoing intra-operative spinal cord monitoring during adult and paediatric spinal deformity surgery between Jan 2009 and Dec 2012 were prospectively followed. The use of somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs) was recorded and monitoring outcomes were compared to post-operative clinical neurological outcomes. Compliance with the national ANS/BSCN guidelines was assessed.Aim:
Method:
In Total Hip Arthroplasty (THA), polyethylene wear reduction is key to implant longevity. Oxidized Zirconium (OxZi) unites properties of a ceramic bearing surface and metal head, producing less wear in comparison to standard Cobalt-Chromium (CoCr) when articulating with Cross-linked polyethylene (XLPE) in vitro. This study investigates in vivo polyethylene (PE) wear, outcomes and complications for these two bearing couples in patients at 5 year follow-up 400 patients undergoing THA across four institutions were prospectively randomised into three groups. Group I received a cobalt-chrome (CoCr) femoral head/ cross-linked polyethylene (XLPE) liner; Group II received an OxZi femoral head/ ultrahigh molecular weight polyethylene (UHMWPE) liner; Group III received an OxZi femoral head/XLPE liner. All bearing heads were 32 mm. Linear wear rate was calculated with Martell computer software. Functional outcome and complications were recorded.Introduction
Methods
Pyogenic spinal infection (PSI) is an increasingly common presentation to spinal units in the UK. Its investigation and diagnosis is often delayed. The purpose of this study was to determine the prognostic significance of the inflammatory marker levels on admission on achieving a positive microbiological diagnosis in patients with PSI. Retrospective case series review of all patients presenting with PSI to our unit.Objective
Study design
The purpose of this study is to describe and validate a CT based classification of lumbosacral segment abnormalities. 400 CT scans were retrospectively reviewed, a classification devised and incidence of abnormalities recorded. 5 types of abnormality were identified. Type 0 is normal; Type 1 describes an asymmetrical shortening of the iliolumbar ligament; Type 2's have the transverse process of L5 within 2 mm of the sacrum but not forming a joint; Type 3's have formed a diarthrodial joint, with 3A's showing no evidence of degeneration and 3B's displaying degenerative changes; In type 4's the transverse process and sacrum have fused; Type5's have involvement of L4. In order to validate the classification, 40 scans were selected with a full cross section of types. 4 independent observers classified each scan in 2 separate sessions, 2 weeks apart.Objective
Method
To highlight the cardiovascular responses of a trainee and supervising consultant while performing Total Knee Arthroplasty (TKA) and to demonstrate the impact that supervision has on both their responses. A third year orthopaedic trainee and his consultant underwent non-invasive, continuous cardiac monitoring while performing three primary TKAs. The consultant performed one TKA with the trainee assisting. The trainee then performed two TKAs as primary surgeon. The consultant supervised one TKA scrubbed and the other un-scrubbed. A third person noted the timing of each distinct intra-operative step. A significant peak was defined as an increase in heart rate (HR) of >10%.Purpose
Methods
Computer assisted surgery is becoming more prevalent in spinal surgery with most published literature suggesting an improvement in accuracy and reduction in radiation exposure. This has been particularly highlighted in scoliosis surgery with regard to the placement of pedicle screws. Anecdotally this has been challenged with concerns with regard to the steep learning curve using this equipment and the high cost of purchasing said systems. The more traditional technique utilises the surgeon's knowledge of anatomic landmarks and tactile palpation added with fluoroscopy to place pedicle screws. We retrospectively looked at 161 scoliosis corrections performed using this technique over three years by 3 main surgeons at the same centre (Frenchay). With an average of 10 levels per procedure and over 2000 pedicle screws inserted. We reviewed the radiation time exposure and dose of radiation given during each case. Our results compared favourably to published data using computer and robot assisted surgery with an average exposure time of 80 seconds and a mean dose of 144 mGy using a standard C-arm guided fluoroscopy. Our study suggests that armed with good surgical knowledge and technique it is possible to obtained low levels of radiation exposure of benefit to both patient and the operating team.
Lumbar myelography was a commonly performed procedure but was superseded by MRI and CT which were low risk and provided cross-sectional information. The majority of MRI and CT evaluations are static and supine whereas myelography may be loaded and dynamic. This study evaluates the role of myelography in patients with degenerative scoliosis in a modern surgical practice. Patients with degenerative scoliosis and full imaging (plain radiographs, supine MRI, myelography, including CT myelography) were identified from our database between 2006-2009. Differences between findings of MRI and myelography/CT myelography were noted and whether this subsequently affected treatment. 21 patients fulfilled inclusion criteria. Mean age 68 (45-82), 17 females. 18/21(85.7%) myelograms revealed findings not seen on MRI. 15 patients had a single abnormality, 1 had two and in 2 patients there were 3 new abnormalities. These were facet/ligamentous bulging in 13, a single spondylolisthesis, retrolisthesis and lateral subluxation. On CT a foraminal osteophyte and a pars defect were seen. In 4 cases supine investigation revealed more than MRI. In 7 patients management changed as a result of myelography/CT. There have been no complications of myelography in our unit of the total 270 performed. Myelography is a safe and useful tool in the management of patients with degenerative scoliosis. MRI scan alone understates the true nature of central and lateral recess stenosis. Not only does myelography show more stenosis in the loaded spine, but static myelography and CT myelography are also an invaluable tool in these patients.
Post traumatic stress disorder (PTSD) is well recognised in children having repeated medical/surgical procedures. It has been suggested that it is common in young children undergoing growing rod treatment with ongoing lengthening and the inevitable accompanying complications. We present an index case history, review the literature in order to infer a correlation for the incidence of PTSD and discuss diagnosis and management. We present an index case history of PTSD in a young child undergoing growing rod treatment for scoliosis. The literature was reviewed for PTSD in paediatric surgery and pathologies requiring multiple treatments. Spinal surgery is compared with paediatric cancer, burns, organ failure/transplant, cardiopulmonary disease, inflammatory bowel disease, cystic fibrosis and limb lengthening. No published studies examine PTSD in children undergoing multiple spinal surgeries. One paper reports that children undergoing growing rod treatments show “behavioural alterations” and changes in psychosocial behaviour, including anxiety on entering the operating room and broken rod worries. A recent spine meeting presentation referred to this. Psychosocial problems occur in up to 30% of children with chronic or life-threatening illnesses which involve ongoing treatments. Factors such as age, parental anxiety and previous adverse medical experiences influence anxiety, depression and PTSD. Based on our index case and methodological correlation with similar pathologies, we fell that PTSD is a genuine concern in children who have repeated spinal operations. This paper is part of an ongoing study, but we believe that the spinal community should be aware of this diagnosis and its management. Ethics approval: Audit Interest Statement: None