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Bone & Joint Research
Vol. 5, Issue 6 | Pages 206 - 214
1 Jun 2016
Malak TT Broomfield JAJ Palmer AJR Hopewell S Carr A Brown C Prieto-Alhambra D Glyn-Jones S

Objectives. High failure rates of metal-on-metal hip arthroplasty implants have highlighted the need for more careful introduction and monitoring of new implants and for the evaluation of the safety of medical devices. The National Joint Registry and other regulatory services are unable to detect failing implants at an early enough stage. We aimed to identify validated surrogate markers of long-term outcome in patients undergoing primary total hip arthroplasty (THA). Methods. We conducted a systematic review of studies evaluating surrogate markers for predicting long-term outcome in primary THA. Long-term outcome was defined as revision rate of an implant at ten years according to National Institute of Health and Care Excellence guidelines. We conducted a search of Medline and Embase (OVID) databases. Separate search strategies were devised for the Cochrane database and Google Scholar. Each search was performed to include articles from the date of their inception to June 8, 2015. Results. Our search strategy identified 1082 studies of which 115 studies were included for full article review. Following review, 17 articles were found that investigated surrogate markers of long-term outcome. These included one systematic review, one randomised control trial (RCT), one case control study and 13 case series. Validated surrogate markers included Radiostereometric Analysis (RSA) and Einzel-Bild-Röntgen-Analyse (EBRA), each measuring implant migration and wear. We identified five RSA studies (one systematic review and four case series) and four EBRA studies (one RCT and three case series). Patient Reported Outcome Measures (PROMs) at six months have been investigated but have not been validated against long-term outcomes. Conclusions. This systematic review identified two validated surrogate markers of long-term primary THA outcome: RSA and EBRA, each measuring implant migration and wear. We recommend the consideration of RSA in the pre-market testing of new implants. EBRA can be used to investigate acetabular wear but not femoral migration. Further studies are needed to validate the use of PROMs for post-market surveillance. Cite this article: T. T. Malak, J. A. J. Broomfield, A. J. R. Palmer, S. Hopewell, A. Carr, C. Brown, D. Prieto-Alhambra, S. Glyn-Jones. Surrogate markers of long-term outcome in primary total hip arthroplasty: A systematic review. Bone Joint Res 2016;5:206–214. DOI: 10.1302/2046-3758.56.2000568


Bone & Joint Research
Vol. 11, Issue 4 | Pages 239 - 250
20 Apr 2022
Stewart CC O’Hara NN Bzovsky S Bahney CS Sprague S Slobogean GP

Aims. Bone turnover markers (BTMs) follow distinct trends after fractures and limited evidence suggests differential levels in BTMs in patients with delayed healing. The effect of vitamin D, and other factors that influence BTMs and fracture healing, is important to elucidate the use of BTMs as surrogates of fracture healing. We sought to determine whether BTMs can be used as early markers of delayed fracture healing, and the effect of vitamin D on BTM response after fracture. Methods. A total of 102 participants aged 18 to 50 years (median 28 years (interquartile range 23 to 35)), receiving an intramedullary nail for a tibial or femoral shaft fracture, were enrolled in a randomized controlled trial comparing vitamin D. 3. supplementation to placebo. Serum C-terminal telopeptide of type I collagen (CTX; bone resorption marker) and N-terminal propeptide of type I procollagen (P1NP; bone formation marker) were measured at baseline, six weeks, and 12 weeks post-injury. Clinical and radiological fracture healing was assessed at three months. Results. CTX and P1NP concentrations peaked at six weeks in all groups. Elevated six-week CTX and P1NP were associated with radiological healing at 12 weeks post-injury (odds ratio (OR) 10.5; 95% confidence interval 2.71 to 53.5, p = 0.002). We found no association between CTX or P1NP and functional healing. Baseline serum 25(OH)D showed a weak inverse relationship with P1NP (p = 0.036) and CTX (p = 0.221) at 12 weeks, but we observed no association between vitamin D supplementation and either BTM. Conclusion. Given the association between six-week BTM concentrations and three-month radiological fracture healing, CTX and P1NP appear to be potential surrogate markers of fracture healing. Cite this article: Bone Joint Res 2022;11(4):239–250


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XLIII | Pages 6 - 6
1 Sep 2012
Monda M Cullen N Singh D Goldberg A
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Introduction. The Z or “scarf” osteotomy was first described by Meyer in 1926 and then by Burutaran in 1976. It was later popularised by Weil in the USA and Barouk in Europe in the 1990's and is now an accepted technique that forms part of a surgeons' armamentarium. The theory of Diffusion of Innovations was described by Rogers in 1962 to explain how novel ideas are accepted into practice across different industries, including medicine. It has never previously been used to study the adoption of ideas in foot and ankle surgery. Methods. This paper uses publication volume as a surrogate marker for adoption, as described previously by the authors. Briefly, a systematic review of the literature was carried out. MESH headings included ‘Hallux Valgus’, and ‘osteotomy’ or ‘SCARF’ or ‘Z osteotomy’ or ‘bunionectomy’. 2818 publications were identified and the abstracts were reviewed excluding 2699 publications for non-relevance. The data was analysed by year of publication, country of origin, as well as for level of evidence. Results. There were 120 publications relating to SCARF osteotomy, which when plotted on a graph produced an s shaped curve. 58% of publications came from Europe and 38% from the USA. There was only a single level 1 paper published in 2008. Discussion. This study confirms that publication volume is a surrogate marker for adoption and that SCARF osteotomy became adopted by the late 2000's as indicated by the plateau on an s-shaped curve. Post market surveillance has led to a further rise in recent publications indicating that certain issues still need resolving before the laggards adopt this technique. Despite SCARF having been around for more than 80 years, very little high level evidence has been published of its effectiveness. Recommendations are made as to how future innovations should be introduced in foot and ankle surgery


The Bone & Joint Journal
Vol. 99-B, Issue 1 | Pages 51 - 58
1 Jan 2017
van der Woude JAD Wiegant K van Heerwaarden RJ Spruijt S Emans PJ Mastbergen SC Lafeber FPJG

Aims. Knee joint distraction (KJD) is a relatively new, knee-joint preserving procedure with the goal of delaying total knee arthroplasty (TKA) in young and middle-aged patients. We present a randomised controlled trial comparing the two. Patients and Methods. The 60 patients ≤ 65 years with end-stage knee osteoarthritis were randomised to either KJD (n = 20) or TKA (n = 40). Outcomes were assessed at baseline, three, six, nine, and 12 months. In the KJD group, the joint space width (JSW) was radiologically assessed, representing a surrogate marker of cartilage thickness. Results. In total 56 patients completed their allocated treatment (TKA = 36, KJD = 20). All patient reported outcome measures improved significantly over one year (p < 0.02) in both groups. At one year, the TKA group showed a greater improvement in only one of the 16 patient-related outcome measures assessed (p = 0.034). Outcome Measures in Rheumatology-Osteoarthritis Research Society International clinical response was 83% after TKA and 80% after KJD. A total of 12 patients (60%) in the KJD group sustained pin track infections. In the KJD group both mean minimum (0.9 mm, standard deviation (. sd. ) 1.1) and mean JSW (1.2 mm, . sd. 1.1) increased significantly (p = 0.004 and p = 0.0003). Conclusion. In relatively young patients with end-stage knee osteoarthritis, KJD did not demonstrate inferiority of outcomes at one year when compared with TKA. However, there is a high incidence of pin track infection associated with KJD. Cite this article: Bone Joint J 2017;99-B:51–8


Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_7 | Pages 13 - 13
1 Apr 2014
Shields D Marsh M Aldridge S Williams J
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The management of displaced forearm diaphyseal fractures in adults is predominantly operative. Anatomical reduction is necessary to infer optimal motion and strength. The authors have observed an intraoperative technique where passive pronosupination is examined to assess quality of reduction as a surrogate marker for active movement. We aimed to assess the value of this technique, but intentionally malreducing a simulated diaphyseal fracture of a radius in a cadaveric model, and measuring the effect on pronosupination. A single cadaveric arm was prepared and pronation/supination was examined according to American Academy of Orthopaedic Surgeons guidance. A Henry approach was then performed and a transverse osteotomy achieved in the radial diaphysis. A volar locking plate was used to hold the radius in progressive amounts of translation and rotation, with pronosupaintion measured with a goniometer. The radius could be grossly malreduced with no effect on pronation and supination until the extremes of deformity. The forearm showed more tolerance with rotational malreduction than translation. Passive pronation was more sensitive for malreduction than supination. The use of passive pronosupination to assess quality of reduction is misleading


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_11 | Pages 48 - 48
1 Jun 2016
Mayne A Davies P Simpson J
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Introduction. Patients with asymptomatic bacteriuria (ASB) have a significantly increased risk of both superficial wound infection and deep infection following arthroplasty. Debate continues as to whether treatment of pre-operative ASB reduces the risk of subsequent prosthetic joint infection. Patients/Materials & Methods. All arthroplasty units in Scotland were contacted by telephone and asked a standard series of questions regarding pre-operative urine testing in arthroplasty patients. A review of the literature was also performed. Results. All arthroplasty units in Scotland test all patients’ urine pre-operatively. 55% of clinics dipstick urine and send a midstream urine (MSU) sample if dipstick positive. 45% send an MSU without urine dipstick testing. All treat a positive MSU with oral antibiotics via the patient's GP practice. Discussion. Historically all arthroplasty patients have had urine testing as part of their routine pre-operative assessment, and this remains current British Hip Society guidance. Globally, antibiotic use is under increasing scrutiny. The evidence for treating pre-operative ASB with antibiotics appears to be lacking but this study suggests the majority of arthroplasty units continue to test for and treat ASB. Locally, this practice has been increasingly questioned by microbiologists and general practitioners. Irrespective of antibiotic treatment, we believe identifying patients with pre-operative ASB remains useful as ASB appears to represent a surrogate marker for immunocompromise. This allows patients to be warned of the increased infection risk and these patients may require altered peri-operative prophylactic antibiotic cover depending on local policy. Conclusion. Evidence for pre-operative antibiotic treatment of ASB is lacking but the majority of arthroplasty units continue this practice. Identification of pre-operative ASB is useful to identify increased infection risk and need for potential altered prophylactic antibiotic cover. We recommend formation of a consensus among arthroplasty surgeons to guide practice


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 5 | Pages 686 - 692
1 May 2007
Bolland BJRF New AMR Madabhushi SPG Oreffo ROC Dunlop DG

The complications of impaction bone grafting in revision hip replacement includes fracture of the femur and subsidence of the prosthesis. In this in vitro study we aimed to investigate whether the use of vibration, combined with a perforated tamp during the compaction of morsellised allograft would reduce peak loads and hoop strains in the femur as a surrogate marker of the risk of fracture and whether it would also improve graft compaction and prosthetic stability. We found that the peak loads and hoop strains transmitted to the femoral cortex during graft compaction and subsidence of the stem in subsequent mechanical testing were reduced. This innovative technique has the potential to reduce the risk of intra-operative fracture and to improve graft compaction and therefore prosthetic stability


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_16 | Pages 58 - 58
1 Apr 2013
Tobita K Okazaki H Sato W Matsumoto T Bessho M Ohashi S Ohnishi I
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The most important issue in the assessment of fracture healing is to acquire information about the restoration of the mechanical integrity of bone. Many researchers have attempted to monitor stiffness either directly or indirectly for the purpose of assessing strength, as strength has been impossible to assess directly in clinical practice. The purpose of this study was thus to determine the relationship between bending stiffness and strength using mechanical testing at different times during the healing process. Unilateral, transverse, mid-tibial osteotomies with a 2-mm gap were performed in 28 rabbits. The osteotomy site was stabilized using a double-bar external fixator. The animals were divided into four groups (n=7/group/time point; 4, 6, 8 and 12 weeks). A series of images from micro-computed tomography of the gap was evaluated to detect the stage of fracture healing and a 4-point bending test was performed to measure stiffness and strength. Formation of cortex and medullary canal at the gap was seen in the 12-week group and would represent the remodeling stage. In addition, the relationship between stiffness and strength remained almost linear until at least 12 weeks. However, stiffness recovered much more rapidly than strength. Strength was not fully restored until the later stages of fracture healing. However, the current study demonstrated that stiffness could be monitored as a surrogate marker of strength until at least the remodeling stage


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXVIII | Pages 15 - 15
1 Jun 2012
Cheng K Rumley A Campbell A Lowe G
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The aim of this study was to examine the effects of cement in total knee arthroplasty on markers of inflammation and endothelial dysfunction, as surrogate markers for enhanced risk of vascular disease or precipitation of acute vascular events post-operatively. A total of 36 patients were recruited, with 18 in each of the cemented and uncemented groups. Both groups were matched for age, sex and body mass index. Venous blood samples were taken pre-operatively, day 1 and day 7 post-operatively. Serum levels of interleukin 6 (IL6), tumour necrosis factor (TNF□?, e-selectin, Von willebrand factor (vWF), tissue plasminogen activator (tPA) and soluble CD40 ligand were analysed. Also, real time analysis of the expression of CD40 and CD14/CD42a aggregates on monocytes was carried out using flow cytometry. Patients were excluded from the study if there were signs of either superficial or deep infection. The only variable to demonstrate a significant difference between the two groups was the CD1442a count. There was a significant difference in the first 24 hours (p=0.00) and from day 1 to day 7 (p=0.02). Our study suggests that the use of bone cement causes a significant rise in CD1442a count which has been linked to atherothrombosis and acute coronary syndromes. These changes may explain the increased incidence of venous thrombosis and thromboembolism post-operatively. However more research required in this field to delineate the exact pathways involved


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 83 - 83
1 Mar 2010
Pérez JR Borrás J Tejeda A Martí L Sanz R
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Introduction and Objectives: The aim of this study is to characterize cartilage perfusion and determine the degree of cartilage lesion using MRI during the injection of a paramagnetic contrast medium in pharmacokinetic models with the aim of obtaining the corresponding dynamic parameters (permeability and fraction of extracellular extravascular volume). Materials and Methods: We included 20 patients with patellar cartilage alterations in this study and proceeded to carry out their clinical assessment. The patients were randomly chosen for the glucosamine sulphate group or the placebo group. Both groups began treatment immediately after the first MR and continued uninterrupted treatment until the second exam 6 months later. Results: in patients treated with glucosamine sulphate significant differences were found between pain reported by the patients and their functional score results. There are also statistically significant differences in the Ktrans parameter, with higher values in the group that received glucosamine sulphate, both for arthritis and for chondromalacia. Discussion and Conclusions: Glucosamine sulphate has an effect on the vascular properties and metabolism of cartilage. There was a strong relationship between treatment and increased cartilage vascular permeability (Ktrans): This makes it possible for us to suggest that the measurement of capillary permeability could be a surrogate marker for determining the effect of 6 months treatment with glucosamine sulphate on the metabolism of degenerated cartilage


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 548 - 548
1 Nov 2011
Hart A Davda K Lali F Skinner J Sampson B
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Introduction: Local problems of metal on metal (MOM) hip arthroplasty such as pseudotumours, neck thinning and osteolysis maybe related to concentrations of cobalt and chromium ions in the synovial fluid. There is little reported on these values. Our aim was to determine the range of metal ion levels in synovial fluid, and to investigate the relationship between these samples and simultaneous blood samples. Methods: Synovial fluid and whole blood samples were taken from 30 consecutive patients at the time of revision surgery for a painful MOM hip. Aspirated fluid was not visibly contaminated with blood. Impants were in situ for a mean period of 31 months. All had normal renal function. Samples were analysed using ICP mass spectrometry and compared with 10 samples from patients without implants. Results: The mean (and range) of synovial fluid metal ion levels were 1965 ug/l (30 to 13618) and 6265 ug/l (11 to 81630) for Cobalt and Chromium respectively. There was a good correlation between synovial and blood levels for both cobalt (R=0.65, p = 0.0001) and chromium (R = 0.59, p = 0.006). Discussion and Conclusion: Metal ions in synovial fluid from MOM hips are generated from wear of the bearing surfaces, the correlation with blood metal ion levels, shown in this study, suggest that blood levels may be used as surrogate marker for hip wear rate. Our range of synovial fluid metal ion levels may be useful for those conducting in vitro studies on the biocompatibility of MOM hips


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_IX | Pages 44 - 44
1 Mar 2012
Cheng K Westwater J Thomas J Rumley A Lowe G Campbell A
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Aim. To examine the effects of total knee arthroplasty on markers of inflammation and endothelial dysfunction, as surrogate markers for enhanced risk of vascular disease or precipitation of acute vascular events post-operatively. Methods. All patients undergoing an elective uncemented total knee arthroplasty at a district general hospital were approached at the pre-assessment clinic. The study was explained and the patients were enrolled into the study following written consent. Venous blood samples were taken pre-operatively, day 1 and day 7 post-operatively. Serum levels of interleukin 6 (IL6), tumour necrosis factor (TNF??, e-selectin, Von willebrand factor (vWF), tissue plasminogen activator (tPA) and soluble CD40 ligand were analysed. Also, real time analysis of the expression of CD40 and CD14/CD42a aggregates on monocytes was carried out using flow cytometry. Patients were excluded from the study if there were signs of either superficial or deep infection. Results. Significant rises were seen with vWF, tPA and sCD40L levels up to day 7 (p= 0.01, 0.00. 0.00 respectively). IL6, e-selectin and TNF? levels were also significantly raised up to day 7 (p= 0.017, 0.031, 0.00). Analysis of the flow cytometry data revealed significant rises in the expression of CD40 (p= 0.006) and CD14/CD42a (P= 0.013) on monocytes over the same time period. Conclusion. Our study strongly suggests that patients undergoing an uncemented total knee arthroplasty provokes the release of vasoactive substances within the vasculature. These changes may explain the increased incidence of venous thrombosis and thromboembolism post-operatively as well as a potential increased risk of arterial thrombosis and sequelae from atherosclerotic plaque rupture


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_I | Pages 51 - 52
1 Jan 2011
Penn-Barwell J Fries C Street L Goonewardene S Jeffery S
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Topical Negative Pressure Therapy (TNPT) has gained increasing acceptance as a useful tool in wound management. Since 2002, the Royal Centre for Defence Medicine (RCDM) in South Birmingham has gained considerable experience with managing complex combat trauma with TNPT. The mainstay of managing high-energy combat wounds has changed little over the last century of conflict and remains early debridement, wound lavage, fracture stabilisation and delayed closure. Over the last 10 years the use of TNPT has proved to be a useful adjunct in promoting delayed primary and secondary closure, and is now common practise in the US and UK military medical services. There is however, little level 1 evidence to support the use of TNPT in military trauma. All military patients admitted to Selly Oak Hospital between April 2007 and March 2008 that were treated with TNPT were identified, those whose notes were available were included. 37 cases were included. There was a strong correlation between ISS, NISS, and antibiotic use during TNPT use and the total duration of secondary care. However, we found no correlation between delay to first TNPT application, the frequency or location of TNPT dressing changes and any of our surrogate markers of outcome. TNPT is just one of a number of techniques for managing military high-energy injuries and should not be seen as an alternative to the established principles. The high frequency of TNPT dressing changes is not supported by this research and this should be reflected in the clinical management of patients requiring prolonged TNPT


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_4 | Pages 90 - 90
1 Jan 2016
Van Der Straeten C De Roest B De Smet K
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INTRODUCTION. Systemic levels of metal ions are surrogate markers of in-vivo wear of metal-on-metal hip resurfacings (MoMHRA). The wear-related generation of metal ions is associated with component size and positioning but also with design specific features such as coverage angle, clearance, metallurgy and surface technology. OBJECTIVES. The objective of the study was to investigate whether a hip resurfacing design (ACCIS) with TiNb engineered bearing surfaces would generate less chromium (Cr) and cobalt (Co) ions during and after the run-in phase of wear and whether Ti ions could be detected indicating wear of the coating. METHODS. Whole blood and serum Cr, Co and Ti levels were measured at 3, 6, 12, 24 and 60 months (ICP-MS). RESULTS. The Cr and Co levels were virtually untraceable during the running-in phase till 1 year. After that, there was a significant increase at the 2 years interval and further at the 5 years interval for both Cr and Co. Overall mean 5 years concentrations of Cr 4.8 μg/l (range 0.5–10.5 µg/L) and Co 4.3 μg/l (range 0.7–12.1µg/l)) had evolved above the established acceptable upper limits (Cr < 4.6 μg/l - Co < 4.0μg/l). 1. Elevated whole blood Ti levels were demonstrated in all patients (mean levels of 9.16 μg/l, 12.54 μg/l and 9.17 μg/l at 3,6 and 12 months respectively) with a peak level at 6 months although there was no statistical difference between the measurements at 3, 6, 12 and 24 months. DISCUSSION. These findings correspond with a release of Ti ions from the TiNb surface during the running-in phase. The whole blood Ti levels were higher compared to whole blood Ti levels in the literature for uncemented grit-blasted acetabular and femoral MoMTHA components and Ti plasma spray coated MoMHRA acetabular components. In those reports, the Ti release is due to passive corrosion from non-articulating surfaces (acetabular and/or femoral fixation surfaces) and is thus likely to be less elevated compared to release due to articulating surface wear as with the ACCIS HRA. A remarkable finding was the continuous elevation of Cr and Co ion levels after the TiNb coating seems to have been worn off. This may be due to a change in clearance as the head is slightly migrating into the cup because of the worn-off coating at the cup-head contact area. CONCLUSION. The ACCIS design has no traceable Cr and Co ions in the running in phase because of its TiNb ceramic surface coating that prevents Cr and Co release. Once the coating is worn off, which only happens at the patch area of friction, a release of Co and Cr ions starts. Although TiNb coating allegedly protects the CoCrMo surface from corrosion by acting as a seal, Cr and Co ions continued to increase at 5 years indicating further wear possibly as a result of change in clearance


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_7 | Pages 100 - 100
1 May 2016
Ziaee H Matharu G Daniel J Pynsent P McMinn D
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High short-term failure rates have been observed with a number of metal-on-metal (MoM) hip designs. Most patients require follow-up with blood metal ions, whichprovide a surrogate marker of in-vivo bearing wear. Given these results are used in clinical decision making it is important values obtained within and between laboratories are reproducible. To assess the intra-laboratory and inter-laboratory variability of blood metal ion concentrations analysed by four accredited laboratories. Whole blood was taken from two participants in this prospective study. The study specimen was obtained from a 42 year-old female with ceramic-on-ceramic hip arthroplasty failure resulting in unintended metal-on-ceramic wear and excessively high systemic metal ion levels. The control specimen was from a 52 year-old healthy male with no metal exposure. The two specimens were serially diluted to produce a total of 25 samples with different metal ion concentrations in two different anticoagulants each. Thus 50 samples were sent blinded in duplicate (total 100) to four accredited laboratories (A, B, C, D) to independently analyse blood metal ion concentrations. Ten commercially available reference specimens spiked with different amounts of metal ions were also obtained with known blood metal ion concentrations (range for cobalt 0.15µg/l-11.30µg/l and chromium 0.80µg/l to 37.00µg/l) and analysed by the four laboratories. The intra-laboratory coefficients of variation for repeat analysis of identical patient specimens were 7.32% (laboratory A), 4.64% (B), 7.50% (C), and 20.0% (D). The inter-laboratory variability for the analysis of all 25 samples was substantial. For the unmixed study specimen the laboratory results ranged from a cobalt of 263.7µg/l (D) to 525.1µg/l (D) and a chromium of 13.3µg/l (D) to 36.9µg/l (A). For the unmixed control specimen the laboratory results ranged from a cobalt of 0.13µg/l (B) to 0.77µg/l (D) and a chromium of 0.13µg/l (D) to 7.1µg/l (A). For one of the mixed specimens the laboratory results ranged from a cobalt of 12.50µg/l (A) to 20.47µg/l (D) and a chromium of 0.73µg/l (D) to 5.60µg/l (A). Similar inter-laboratory variation was observed for the other mixed samples. The true mean (standard deviation) of the 10 commercial samples was 4.48µg/l (4.20) for cobalt and 8.97µg/l (10.98) for chromium. This was similar to the values obtained by all four laboratories: mean (standard deviation) cobalt ranged from 3.54µg/l (3.17) in laboratory A to 4.35µg/l (4.13) in laboratory D, and chromium ranged from 7.76µg/l (9.50) in laboratory B to 9.55µg/l (9.16) in laboratory A. When testing patient samples, large variations existed both between and within four laboratories accredited to perform analysis of blood metal ion concentrations. However, this was not the case when assessing commercially spiked samples which are regularly used to validate laboratory testing. This is of great clinical concern and could lead clinicians to either recommend unnecessary revision or delay surgery, with both having the potential to adversely affect patient outcomes. It is recommended that laboratories use patient samples to assess the accuracy and reproducibility of the analyses performed. This may also assist in explaining the variations observed in this study


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_III | Pages 475 - 476
1 Jul 2010
Entz-Werlé N Lavaux T Modrowski D Lasthaus C Guérin E Brugières L Marec-Berard P Tabone M Schmitt C Gentet J Gaub M
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Despite the recent progress, non-metastatic pediatric osteosarcomas have now a 5-year overall survival (OS) around 75% and the metastatic forms are decreasing to 20–30%. To increase these survival rates, new molecular approaches are on development to understand and highlight new candidates for targeted therapies. Tyrosine kinase receptors (TKR) are one of this target class, where new drugs were especially developped, screening now a large spectrum of TKR. After the demonstration among cancers of TKR’s clinical utility as surrogate markers to guide the selection of patients susceptible to respond to these treatments, this success was recently tempered in part because of cancers developping resistance mechanisms to these drugs. A study was conducted to evaluate the interest of these molecular targets among pediatric osteosarcomas. Materiel and methods: 91 pediatric patients treated homogeneously with the French OS94 protocol were included in this analysis. Allelotyping, real-time quantitative PCR (QPCR), sequencing and immunhistochemistry were performed to analyse the following targets: EGFR, MET, PDGFRA, KIT and ERBB2. Results and discussion: Most of these targets were rearranged in more than 45% of the population and mainly deleted. Only 11.4% were amplified at MET and 8.6% at PDGFRA. By QPCR, ERBB2 was normal in 78 out of 81 informative patients. Surprinsingly, wild-type KIT protein was amplified in 37%. EGFR was rearranged by allelotyping in 48% and QPCR evaluation just started. MET amplified subgroup is linked to a worst OS than normal and deleted subgroups (p=0.04) whereas PDGFRA amplified tumors tend to be significantly linked to a better patient OS (p=0.08). Considering all amplified subgroups, no ovelap was found as if an osteosarcoma could only be amplified for one gene. This observation could be considered as a way to increase the potential targeted populations where the use of large spectrum TKR inhibitors would be useful in osteosarcoma treatment


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_III | Pages 460 - 460
1 Jul 2010
Stark M Dantonello T Winkler P Leuschner I Bölling T Seitz G Hallmen E Veit-Friedrich I Bielack S Paulussen M Ladenstein R Kazanowska B Ljungman G Klingebiel T Koscielniak E
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Tumour volume reduction (i.e. response), assessed following induction chemotherapy, has been identified as a prognostic factor for localized embryonal rhabdomyosarcoma (RME) in the CWS studies. In combination with other risk factors, it has been used to stratify secondary local and systemic treatment. It is however unclear whether the poor outcome of non-responders is due to insufficient local and/or systemic post-induction treatment. We analyzed post-induction therapy of RME-patients < 21 years with unresected localized tumours (IRS-III) and poor response (NR, i.e. < 33% tumour volume reduction) treated 1980–2005 in five consecutive CWS-trials. The NR were reviewed and subclassified (Objective Response (OR; i.e.< 33%–0%) vs. Stable Disease/Progression (PD; i.e. no reduction)). From 758 IRS-III RME-patients, 59 were NR (n=34 OR, n=25 PD). Induction for NR included dactinomycin, vincristine, alkylators ± anthracyclines in all patients. There were no significant differences in comparison of the control group and NR with regard to age, size, TN-classification, apart from site (p=0.04), and no differences regarding these parameters between OR and PD. Twenty-four NR received continued induction chemotherapy, n=32 other combinations, and n=3 no further chemotherapy following response assessment. Four patients were treated with additional high-dose chemotherapy. Fourty-two NR were irradiated with a median dose of 48Gy (control group: 45Gy). In 20 NR, the tumours were completely resected. As of 9/2008, with a median follow-up of 4.5 years (range: 0.9–12.1) for NR survivors, 34 NR are alive in CR. Reasons for the 25 deaths were: local/combined failure (n=21), systemic failure (n=1), and other reasons (n= 3). 5-yrs-OS was 71±4% for the control group, 78±15% for OR, but only 43±15% for PD (p< 0.01). Response is an important surrogate marker of outcome, but per se associated with a poor prognosis only in tumours without any volume regression to induction chemotherapy. Ineffective local control drives mortality in these patients


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 52 - 52
1 Mar 2010
Egan C Cummins F Kenny P
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Introduction: With the advent of harder wearing metal alloys such as cobalt chrome the technique of hip surface replacement has been resurrected. It is becoming an increasingly popular especially with the younger patient with end-stage hip arthritis. In this study we seek to demonstrate this procedure’s short term success rate for Cappagh and to demonstrate the new Joint Registry in action which has been collating data for the last 2 years. Methods: The Bluespiers online database was used to identify 200 consecutive primary hip resurfacing performed in Cappagh National Orthopaedic Hospital between January 1st 2006 and January 31st 2008. Patients completed a WOMAC 3.1 Osteoarthritis assessment and SF-36 General Health survey before their operation and at their 1st Joint Registry Clinic Review, typically between five and 9 months post-operatively. Findings: 200 hip resurfacing procedures by 7 surgeons were identified between January 1st 2006 and January 31st 2008. The mean patient age was 55 years(range, 23 to 81 years). 48 (32%) were female and 152 (68%) were male. Two post-operative femoral neck fractures were recorded which were converted to THR. We used the SF-36 score as a surrogate marker of overall subjective health and quality of life. The average preoperative SF-36 score was 50.93 (5 to 94.4). The average SF-36 score at 1st Joint Review Clinic visit was 77.55 (23.77–100). This demonstrates an average improvement of 24.44 (−17.69 to 59.75). As a measure of arthritis severity we will use the WOMAC 3.0 score as a surrogate. The average preoperative WOMAC score was 52.95 (4–92) and the average WOMAC score at 1st Joint Registry Review was 16.11 (0–75). This demonstrates an average decrease in WOMAC score of 34.46 (−29 to 83). Discussion: Hip surface replacement in Cappagh as recorded by the Joint registry has good success in treating hip arthritis with good improvement of quality of life. We would hope to demonstrate with the joint registry continuing long-term success of this treatment


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 456 - 456
1 Sep 2012
Grammatopoulos G Pandit H Mellon S Glyn-Jones S Gundle R Mclardy-Smith P Murray D Gill H
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INTRODUCTION. Studies have suggested that there is a reduction in head-neck-ratio (HNR) associated with MoMHRA. A reduction in HNR at operation would decrease range of movement and increase impingement risk. Impingement could lead to 20 edge loading, increasing wear. Serum ion levels of Chromium (Cr) and Cobalt (Co) are surrogate markers of wear. Although acetabular component orientation has been shown to contribute to wear and PT development, the role of a decrease in HNR has only been highlighted in PT development. This study aimed to measure changes in HNR that occur at resurfacing and determine any gender- and component size-specific differences. In addition it aimed to determine whether changes in HNR could be associated with increased wear. METHODS. 84 patients (56M: 28F) with unilateral MoMHRA were included. The mean age at surgery was 57 years. The mean femoral component was 49mm. Components were considered small if <45mm, average if between 45–50mm and large if >50mm. Three designs were implanted; BHR, C+ and Recap. The average follow up was 4 years. All patients had Cr/Co levels measured at follow up. Patients were considered to have high ions if Cr and Co levels were 5.1ppb and 4.4ppb respectively. Pre-operative HNR (HNRpre) and the post-operative HNR (HNRpost) were made from the respective pelvic radiographs. Assuming a 2mm thick cartilage layer, the HNR based on the diameter of the articular cartilage pre-operatively (HNRart) was calculated. The immediate changes in HNR as a result of the operation were expressed relative to articular HNR pre-op:. HNRartpost=HNRpost–HNRart. RESULTS. The changes in HNR at operation were significantly negatively correlated with HNRpre, (p<0.001), (rho=−0.77). Females had greater ion levels (p=0.013) and smaller components (p<0.001). Females had bigger pre-operative HNRart and were downsized more (p<0.001). Similarly, patients with small components had higher ions (p=0.032). They had greater HNRart and were downsized more (p<0.001) Twelve patients comprised the high ion group. These patients had smaller components (p=0.004), greater HNRart and were down-sized significantly more at resurfacing (p<0.001). DISCUSSION. This study highlights HNR changes that occur in resurfaced hips. Females, patients with small components and patients in the high ion group had higher pre-operative HNR and were downsized more at operation. Femoral downsize, would probably increase impingement risk, lead to secondary edge loading and contribute to greater incidence of wear related problems


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVII | Pages 578 - 578
1 Sep 2012
Grammatopoulos G Judge A Pandit H Mclardy-Smith P Glyn-Jones S Desmet K Murray D Gill H
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INTRODUCTION. Although simulation studies have shown superior wear properties of metal-on-metal articulations, increased concern exists regarding the excess in-vivo wear of a small number of Metal-on-Metal-Hip-Resurfacing (MoMHRA) implants. Serum ion levels of Chromium (Cr) and Cobalt (Co) are surrogate markers of wear. Risk factors associated with increased wear include female gender, small components, dysplasia, cup orientation outside safe zone and femoral head downsize during surgery with an associated decrease in Head-Neck-Ratio (HNR). However, these factors are interlinked. This study aims to identify the factors that are most important for subsequent wear of MoMHRA, by performing a multivariate analysis. METHODS. 206 patients (124M: 82F) with unilateral MoMHRA were included in this study. The average follow up was 3.3 years. All patients had Cr/Co levels measured at follow up. Inclination and anteversion of each cup were measured using EBRA. Cups were analysed as being within or outside the previously defined optimum-zone. HNR measurements were made from pre-operative (HNRpre) and post-operative (HNRpost) radiographs. The immediate changes in HNR (downsize/upsize of femoral head) as a result of the operation were expressed as:. HNRprepost=HNRpost–HNRpre. Multivariate linear regression modelling was used to explore the association between measures of ions with the following predictor variables (gender, age, diagnosis, femoral component size, orientation of the acetabular component, head/neck ratio and position of femoral stem). Analyses were carried out separately for each outcome (Cr and Co). Classification and Regression Tree (CART) models were fitted as a complimentary approach to regression modelling. RESULTS. Articular surface downsize followed by cup orientation within/outside optimum zone, followed by cup anteversion followed by gender were the strongest predictors of ion levels. A percentage decrease in HNRartpost, predicted an increase in Cr ion level by 5% (and 6% for Co). If the cup was within the optimum zone this was associated with decreased levels of Cr and Co ions. As acetabular component anteversion increased, levels of ions increased. Gender had a strong effect on ion levels. Adjusting for other variables, the effect of gender was attenuated due to a confounding effect of component size and the amount of femoral head downsize. Predictors identified as important in regression analyses were similar to those produced in the CART model, where the highest levels of ions were seen in patients with a percentage decrease in pre-operative HNR −11.3. DISCUSSION. This analysis shows that (surgical) factors, such as amount of femoral head downsize at operation and whether the cup was orientated within the optimum zone, explained the majority of the variability in ion levels in MoMHRA