Advertisement for orthosearch.org.uk
Results 1 - 20 of 26
Results per page:
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


Bone & Joint 360
Vol. 11, Issue 3 | Pages 38 - 39
1 Jun 2022


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_IV | Pages 586 - 586
1 Nov 2011
Bishop PB Fisher C Quon J Dvorak M
Full Access

Purpose: Clinical practice guideline (CPG) concordant treatment (Ctx) has been shown to be more effective than CPG discordant care (Dtx) in a heterogeneous cohort of patients with acute lower back pain (ALBP). However, patients with underlying spine pathology (e.g. stenosis, disc degeneration, facet joint arthropathy) or without identifiable spine pathology may all present solely with ALBP. At present, it is unknown if underlying spine pathology influences the outcome of Ctx. The purpose of this study was to determine if Ctx is more effective than Dtx in patients with differing underlying spine pathology who present with ALBP. Method: A Two-arm, randomized control trial with stratified analysis. Inclusion: Ages 19–59; QTFSD I, II ALBP < 4 weeks. Exclusion: “Red Flag” conditions, comorbidities contraindicating Ctx. The primary outcome was the difference between Ctx and Dtx Roland Morris Disability (RDQ) scores at 16 weeks post baseline between study groups. Secondary outcomes: differences in Bodily Pain (BP), Physical Functioning (PF) SF-36 domain scores at 16 weeks. Patients were assessed by a spine physician and randomized to Ctx or Dtx. Patients were stratified on the basis of CT or MRI evidence of:. spinal stenosis;. disc degeneration;. facet joint arthropathy; or. no identifiable pathology. Hospital / University Ethics approval was obtained. Results: Eighty-eight patients were recruited; 39 in Ctx & 38 in Dtx group completed the study. Baseline prognostic variables were evenly distributed between groups. Outcomes: mean difference in 16 week RDQ, BP and PF scores between Ctx and Dtx was statistically greatest in group 4 (p< 0.001). There was no significant clinical improvement in RDQ, BP or PF scores in either the Ctx or Dtx in group 2. Conclusion: Ctx was more effective than Dtx in patients with no identifiable spine pathology and ineffective and equivalent to Dtx in patients with underlying disc degeneration


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_III | Pages 253 - 253
1 Nov 2002
Kawana K Takahashi M Hoshino H Kushida K Nagano A
Full Access

Aim: Urinary C-terminal telopeptide of type I collagen (u-CTx) has been reported to be a sensitive biochemical marker of bone turnover. There have been two assays for urinary CTx, which are u-aCTx and u-BCTx. A newly developed immunoassay for serum CTx (s-CTx) is now available for assessment of bone resorption. We have both evaluated the effects of menopause, and osteoporosis on the measurements of serum CTx and compared them to urinary CTx assays. Subjects: 79 premenopausal healthy women, 80 post-menopausal healthy women, 61 osteoporotic patients with vertebral fractures and 34 osteoporotic patients with hip fractures. Results: Bone resorption markers were increased after menopause. There was no significant difference among s-CTx, u-aCTx and u-BCTx in the T-scores of post-menopausal group over premenopausal group (T -score; s-CTx:2.3, u-aCTx:1.8, u-BCTx:2.1). Patients with vertebral fractures and patients with hip fracture had elevated levels of bone resorption markers compared to age-matched healthy postmenopousal women. There was no significant difference among s-CTx, u-aCTx and u-BCTx in the T-scores against postmenopausal group in vertebral fracture group (T -score; s-CTx:0.8, u-aCTx:0.9, u-BCTx:0.7) and in hip fracture group women (T-score; s-CTx:1.1, u-aCTx: 1.3 u-BCTx: 1.3). Conclusions: These findings indicate that s-CTx reflects the increase of bone resorption associated with menopause and osteoporosis with vertebral fractures and hip fractures


Orthopaedic Proceedings
Vol. 94-B, Issue SUPP_XXXVI | Pages 101 - 101
1 Aug 2012
Pearson R Shu K Divyateja H Seagrave M Game F Jeffcoate W Scammell B
Full Access

Background. Charcot neuropathic osteoarthropathy is a rare, destructive process affecting the bones and joints of feet in patients with diabetic peripheral neuropathy. The aetiology of Charcot remains unknown, although it has been suggested that it is triggered by the occurrence of inflammation in the foot of a susceptible individual, and that the inflammation results in increased osteoclastic activity. Hypothesis. The increased bone turnover in acute Charcot is associated with increased concentrations of pro-inflammatory cytokines, related signalling peptides and bone turnover markers. Methods. 17 patients newly presenting with acute Charcot in diabetes and 16 non-diabetic patients without neuropathy undergoing elective forefoot surgery provided informed consented to participate. Samples of bone were taken by needle biopsy, and were stained with H&E to determine bone architecture and bone remodelling. Serum ALP, CTX, OPG and sRANKL TNF, IL1-beta, IL6 and CRP were measured by immunoassay. Blood was taken from the dorsal foot vein of both the affected and the unaffected foot, as well as an antecubital vein. Results. Classic histopathology features of fracture and bone remodelling were evident in Charcot bone biopsies. Systemic circulating concentrations in the Charcot group antecubital vein for both IL6 and OPG were significantly greater than in controls (p<0.05). There were no significant differences between the dorsal vein concentrations of any analyte when the affected and unaffected feet were compared. However, in patients with an acute Charcot foot the concentration of OPG, ALP and CTX was higher in sera from the dorsal vein of affected foot when compared to controls (p<0.05), this difference was highly significant for IL6 (p<0.001). Conclusion. The elevation in CTX observed in the affected foot in patients with an acute Charcot foot reflects the bone breakdown and remodelling which is present. The higher circulating concentration of IL-6 in the Charcot patient group, reflects the inflammation which is present and which is thought to be central to the development of the condition. Although OPG values were significantly greater in Charcot than control group, circulating concentrations of OPG are known to be higher in diabetes


The Bone & Joint Journal
Vol. 104-B, Issue 12 | Pages 1352 - 1361
1 Dec 2022
Trovarelli G Pala E Angelini A Ruggieri P

Aims

We performed a systematic literature review to define features of patients, treatment, and biological behaviour of multicentric giant cell tumour (GCT) of bone.

Methods

The search terms used in combination were “multicentric”, “giant cell tumour”, and “bone”. Exclusion criteria were: reports lacking data, with only an abstract; papers not reporting data on multicentric GCT; and papers on multicentric GCT associated with other diseases. Additionally, we report three patients treated under our care.


Orthopaedic Proceedings
Vol. 98-B, Issue SUPP_18 | Pages 7 - 7
1 Nov 2016
Murray I Gonzalez Z Baily J Iredale J Simpson H Peault B Henderson N
Full Access

Scar tissue formation secondary to acute muscle injury, surgical wounding and compartment syndrome can result in significant functional impairment and predispose to further injury. The source of fibroblasts, and the molecular mechanisms driving their activation and persistence in skeletal muscle fibrosis are not known. We hypothesized that cells expressing PDGFRβ become fibroblasts in response to injury and that targeting αv integrins in these cells reduces skeletal muscle fibrosis. We used double-fluorescent reporter mice to demonstrate that cells expressing PDGFRβ become activated myofibroblasts in response to cardiotoxin (CTX) induced skeletal muscle injury. Following injury, PDGFRβ+ cells moved from perivascular locations into the interstitium in a distribution characteristic of fibroblasts, and showed marked induction of fibroblastic genes including αSMA and collagen1 (all p<0.0001). To confirm that αv integrins present on PDGFRβ cells critically regulate skeletal muscle fibrosis we used Itgavflox/flox;PDGFRβ-Cre mice (transgenic mice in which αv integrins are ‘knocked-down’ in PDGFRβ+ cells). These mice were significantly protected from CTX induced fibrosis (p<0.01). To demonstrate potential clinical utility of targeting αv integrins, we used a small molecule inhibitor of αv integrins (CWHM12). Treatment with CWHM12 significantly reduced fibrosis when delivered from the time of injury (p<0.01) and when delivered after the fibrotic response had become established (p<0.01). We have identified a core pathway regulating fibrosis in skeletal muscle. Pharmacologic inhibition of αv integrins has potential clinical utility in the treatment and prevention of skeletal muscle fibrosis


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_8 | Pages 35 - 35
1 Apr 2017
Ciapetti G Fotia C Granchi D Rojewski M Rosset P Gómez-Barrena E Baldini N
Full Access

Background. Delayed bone healing and nonunion are complications of long bone fractures, with prolonged pain and disability. Regenerative therapies employing mesenchymal stromal cells (MSC) and/or bone substitutes are increasingly applied to enhance bone consolidation. Within the REBORNE project, a multi-center orthopaedic clinical trial was focused on the evaluation of efficacy of expanded autologous bone marrow (BM) derived MSC combined with a CaP-biomaterial to enhance bone healing in patients with nonunion of diaphyseal fractures. To complement the clinical and radiological examination of patients, bone turnover markers (BTM) were assayed as potential predictors of bone healing or non-union. Methods. Bone-specific alkaline phosphatase (BAP), C-terminal-propeptide type I-procollagen (PICP), osteocalcin (OC), β-Cross-Laps Collagen (CTX), soluble receptor activator of NFkB (RANKL), osteoprotegerin (OPG) were measured by ELISA assays in blood samples of 22 patients at BM collection and at follow-ups (6, 12 and 24 weeks post-surgery). Results. A significant relationship with age was found only at Visit 6, with an inverse correlation for CTX, RANKL and OC, and positive for OPG. BTM levels were not related to gender. As an effect of local regenerative process, some BTM showed significant changes in comparison to the starting value. In particular, the time course of BAP, PICP and RANKL was different in patients with a successful healing in comparison to patients with negative outcome. The BTM profile indicated remarkable bone formation activity after 12 weeks after surgery. However, the paucity of failed patients in our case series did not allow to prove statistically the role of BTM as predictors of the final outcome. Conclusion. BTM related to bone cell function are useful to measure the efficacy of a regenerative approach based on expanded MSC. Level of evidence. Diagnostic Level IV. Work supported by the EC, Seventh Framework Programme (FP7), through the REBORNE Project, grant agreement no. 241879


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_9 | Pages 106 - 106
1 May 2017
Murray I Gonzalez Z Iredale J Simpson H Peault B Henderson N
Full Access

Background. There are currently no effective treatments for skeletal muscle fibrosis. Myofibroblasts are the major cellular effectors of fibrosis but their origin in muscle is unknown. We report that PDGFRβ (platelet derived growth factor receptor beta) Cre inactivates genes in murine PDGFRβ+ cells and myofibroblasts in muscle with high efficiency. We used this system to delete the integrin αv subunit because of the suggested role of multiple αv integrins as central mediators of fibrosis in multiple organs. Methods. Muscle fibrosis was induced by intramuscular cardiotoxin (CTX) injection. The contribution of PDGFRβ+ cells to fibrosis was assessed in double-flourescent reporter (mTmG) mice under PDGFRβ-Cre control. Itgavflox/flox;PDGFRβ-Cre mice were used to investigate whether loss of αv integrins on PDGFRβ+ cells influences fibrosis development. A small-molecule inhibitor of αv integrins (CWHM12) was used to determine whether pharmacological blockade of αv integrins could attenuate fibrosis. Results. At 21 days following injury PDGFRβ+ cells in mTmG;PDGFRβ-Cre mice were distributed in a manner characteristic of myofibroblasts. PDGFRβ+ cells sorted from injured muscles of mTmG;PDGFRβ-Cre mice showed induction of genes associated with myofibroblastic transition. Itgavflox/flox;PDGFRβ-Cre mice were protected from CTX induced fibrosis, as determined by picrosirius red staining for collagen (p<0.01). Sorted and culture activated αv-null PDGFRβ+ cells demonstrated significant reduction in collagen1 over controls (p<0.05). CWHM12 significantly reduced muscle fibrosis when delivered from the time of injury (prophylactic model: p<0.01) and from day 10 post injury (therapeutic model: p<0.01). Furthermore, CWHM12 inhibited collagen1 expression by PDGFRβ+ cells ex-vivo (p<0.05). Conclusions. PDGFRβ-Cre labels profibrotic cells in skeletal muscle and depletion of αv integrins in these cells reduces muscle fibrosis. Most importantly from a treatment standpoint, pharmacologic inhibition of αv integrins using a small molecule inhibitor may have utility in the prevention and treatment of skeletal muscle fibrosis. Level of Evidence. Basic Science


Orthopaedic Proceedings
Vol. 99-B, Issue SUPP_2 | Pages 11 - 11
1 Jan 2017
Ciapetti G Granchi D Barrena EG Rojewski M Rosset P Layrolle P Donati D Spazzoli B Baldini N
Full Access

Delayed bone healing and nonunion are complications of long bone fractures, with prolonged pain and disability. Regenerative therapies employing mesenchymal stromal cells (MSC) and/or bone substitutes are increasingly applied to enhance bone consolidation. The REBORNE project entailed a multi-center orthopaedic clinical trial focused on the evaluation of efficacy of expanded autologous bone marrow (BM) derived MSC combined with a CaP-biomaterial, to enhance bone healing in patients with nonunion of diaphyseal fractures. To complement the clinical and radiological examination of patients, bone turnover markers (BTM) were assayed as potential predictors of bone healing or non-union. Peripheral blood was collected from patients at fixed time-endpoints, that is at 6,12 and 24 weeks post-surgery for implantation of expanded autologus MSC and bone-like particles. Bone-specific alkaline phosphatase (BAP), C-terminal-propeptide type I-procollagen (PICP), osteocalcin (OC), β-Cross-Laps Collagen (CTX), soluble receptor activator of NFkB (RANKL), osteoprotegerin (OPG) were measured by ELISA assays in blood samples of 22 patients at BM collection and at follow-up visits. A significant relationship with age was found only at 6 months, with an inverse correlation for CTX, RANKL and OC, and positive for OPG. BTM levels were not related to gender. As an effect of local regenerative process, some BTM showed significant changes in comparison to the baseline value. In particular, the time course of BAP, PICP and RANKL was different in patients with a successful healing in comparison to patients with a negative outcome. The BTM profile apparently indicated a remarkable bone formation activity 12 weeks after surgery. However, the paucity of failed patients in our case series did not allow to prove statistically the role of BTM as predictors of the final outcome. Blood markers related to bone cell function are useful to measure the efficacy of a expanded MSC-regenerative approach applied to long bone non-unions. Changes of the markers may provide a support to radiological assessment of bone healing


Bone & Joint Research
Vol. 11, Issue 5 | Pages 304 - 316
17 May 2022
Kim MH Choi LY Chung JY Kim E Yang WM

Aims

The association of auraptene (AUR), a 7-geranyloxycoumarin, on osteoporosis and its potential pathway was predicted by network pharmacology and confirmed in experimental osteoporotic mice.

Methods

The network of AUR was constructed and a potential pathway predicted by Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) terms enrichment. Female ovariectomized (OVX) Institute of Cancer Research mice were intraperitoneally injected with 0.01, 0.1, and 1 mM AUR for four weeks. The bone mineral density (BMD) level was measured by dual-energy X-ray absorptiometry. The bone microstructure was determined by histomorphological changes in the femora. In addition, biochemical analysis of the serum and assessment of the messenger RNA (mRNA) levels of osteoclastic markers were performed.


Aims

This study intended to investigate the effect of vericiguat (VIT) on titanium rod osseointegration in aged rats with iron overload, and also explore the role of VIT in osteoblast and osteoclast differentiation.

Methods

In this study, 60 rats were included in a titanium rod implantation model and underwent subsequent guanylate cyclase treatment. Imaging, histology, and biomechanics were used to evaluate the osseointegration of rats in each group. First, the impact of VIT on bone integration in aged rats with iron overload was investigated. Subsequently, VIT was employed to modulate the differentiation of MC3T3-E1 cells and RAW264.7 cells under conditions of iron overload.


The Bone & Joint Journal
Vol. 104-B, Issue 9 | Pages 1011 - 1016
1 Sep 2022
Acem I van de Sande MAJ

Prediction tools are instruments which are commonly used to estimate the prognosis in oncology and facilitate clinical decision-making in a more personalized manner. Their popularity is shown by the increasing numbers of prediction tools, which have been described in the medical literature. Many of these tools have been shown to be useful in the field of soft-tissue sarcoma of the extremities (eSTS). In this annotation, we aim to provide an overview of the available prediction tools for eSTS, provide an approach for clinicians to evaluate the performance and usefulness of the available tools for their own patients, and discuss their possible applications in the management of patients with an eSTS.

Cite this article: Bone Joint J 2022;104-B(9):1011–1016.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_I | Pages 11 - 11
1 Jan 2004
Thümler P Starker M Weipert A Hannusek S
Full Access

With 3D CT data of proximal femora it is possible to develop a computer programme for optimising femoral component fit and simulation of implantation. The implantation of the femoral stem can be simulated with any femoral component that has cortical press fit. Five different currently used femoral components were virtually “implanted” in over 200 different femoral bone data. Optimal femoral fit was defined, when the component showed best diaphyseal and metaphyseal congruent contact with all CT data available. Position of neck and head were secondary, since an optimal press fit situation had priority in our set-up. Best fit was considered taken cortical contact and reconstruction of joint geometry into account. There were numerous failures in all tested standard components, when correct angle of antetorsion, off-set, and leg length were expected. There were considerably better results with the use of CTX standard prosthesis (CTX-S). The data of this study indicate a high proportion of less optimal fit with femoral standard components tested in this series. Indication for choosing CTX-S femoral components is dependent upon the individual geometry of dysplastic hip joint and the simulation results of standard components using the VIP method


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 264 - 264
1 Sep 2005
Walker S Li G Marsh D Coward SM Finch MB
Full Access

Introduction: Bone mineral density (BMD) is currently the gold standard in predicting osteoporotic fracture, but evidence suggests that over one third of such fractures occur in those with osteopenia or even normal BMD. The level of bone turnover may affect bone quality in these patients independently of BMD. Bone markers have evolved as tools in monitoring anti-resorptive treatment in osteoporosis. Aims: The aim of this study was to investigate if levels of bone markers in postmenopausal women could be used as an adjunct to BMD measurements in the assessment of fragility fracture risk. Patients and Methods: 60 postmenopausal women (30 osteoporotic, 30 with normal BDM) were studied. A single BMD measurement by dual energy x-ray absorptiometry (DEXA) enabled categorisation. Serum bone formation markers (bone specific alkaline phosphatase (BSAP) and osteocalcin (OC)), and resorption marker (C-telopetide of type 1 collagen (CTX)), were measured. History of low trauma fracture was documented for each woman. Results: 36% of the osteoporotic group had experienced at least one fragility fracture. However, the femoral neck and combined spinal BMD in these women was not significantly different from the 64% of osteoporotic women who had no prior fracture. There was also no significant difference in the age of women in both subgroups. Serum bone markers were significantly increased in the osteoporotic fracture subgroup when compared to the non-fracture subgroup and also to the non-osteoporotic controls. The largest increases were seen in the levels of CTX. Smaller increases in all markers were seen when the non-fracture subgroup was compared to the non-osteoporotic control group but these increases did not reach statistical significance. Conclusions: Bone turnover is significantly increased in postmenopausal osteoporotic women with previous fracture compared to both osteoporotic non-fracture counterparts and non-osteoporotic controls. This suggests higher bone turnover will increase fracture risk in osteoporotic women. It is possible that combining 2 or 3 markers to produce an “index of bone turnover” would be a useful tool when used in addition to BMD to identify those at greatest fracture risk


Bone & Joint Research
Vol. 9, Issue 11 | Pages 742 - 750
1 Nov 2020
Li L Xiang S Wang B Lin H Cao G Alexander PG Tuan RS

Aims

Dystrophic calcification (DC) is the abnormal appearance of calcified deposits in degenerating tissue, often associated with injury. Extensive DC can lead to heterotopic ossification (HO), a pathological condition of ectopic bone formation. The highest rate of HO was found in combat-related blast injuries, a polytrauma condition with severe muscle injury. It has been noted that the incidence of HO significantly increased in the residual limbs of combat-injured patients if the final amputation was performed within the zone of injury compared to that which was proximal to the zone of injury. While aggressive limb salvage strategies may maximize the function of the residual limb, they may increase the possibility of retaining non-viable muscle tissue inside the body. In this study, we hypothesized that residual dead muscle tissue at the zone of injury could promote HO formation.

Methods

We tested the hypothesis by investigating the cellular and molecular consequences of implanting devitalized muscle tissue into mouse muscle pouch in the presence of muscle injury induced by cardiotoxin.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 435 - 435
1 Apr 2004
Thümler P Starker M Hanusek S Weipert A
Full Access

Advantages of custom made prosthesis are the 3D-Planing and correction of the head position using the best possible form fit. Considering these properties we examined several off the shelf systems if they can fulfil the requirements to form fit and head position. By using our fit program we simulated the implantation of five different off the shelf systems in more than 200 individual reconstructed femora. The data of these bones were used for constructing a custom made implant, so the best form fit and head position could be compared with the result of the fit. All of the patients were younger than 65 years. The data of the off the shelf prostheses systems came from 3D measurement. All systems were described as anatomical. The fit program is an optimization program which can implant a 3D prosthesis model in a reconstructed 3D femur by variation of all six special parameters simultaneously. Compared to the demands of our custom implants, the results of the virtual implantation of the off the shelf systems, are more or less unsatisfactory. Depending on the acceptable tolerance of the limits in offset, leg lengthening and anteversion up to 50% of the patients could not be treated with a single off the shelf system, when the best form fit was reached sufficiently. Using the results of this examination we enlarged our custom-made prosthesis system with six different sizes of an anatomical like off the shelf prostheses. By perfoming the same fit simulation with our new implants we found that more than 70% of our patients could be treated with this implant sufficiently, when using the same limits. A good correspondence was found between the computer fit, which was calculated in advance, and the postoperative situation. The combined system of custom and off the shelf prostheses in addition with our 3D planning system based on CT examination, leads to new way of choosing the best implant for a single patient. If the virtual implantation of an off the shelf system does not give a satisfying result, the custom-made CTX prosthesis will be chosen for this patient


Bone & Joint Open
Vol. 3, Issue 5 | Pages 359 - 366
1 May 2022
Sadekar V Watts AT Moulder E Souroullas P Hadland Y Barron E Muir R Sharma HK

Aims

The timing of when to remove a circular frame is crucial; early removal results in refracture or deformity, while late removal increases the patient morbidity and delay in return to work. This study was designed to assess the effectiveness of a staged reloading protocol. We report the incidence of mechanical failure following both single-stage and two stage reloading protocols and analyze the associated risk factors.

Methods

We identified consecutive patients from our departmental database. Both trauma and elective cases were included, of all ages, frame types, and pathologies who underwent circular frame treatment. Our protocol is either a single-stage or two-stage process implemented by defunctioning the frame, in order to progressively increase the weightbearing load through the bone, and promote full loading prior to frame removal. Before progression, through the process we monitor patients for any increase in pain and assess radiographs for deformity or refracture.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 459 - 459
1 Apr 2004
Beard H Schultz C Moore R
Full Access

Introduction: Vertebral compression fractures are common in osteoporosis, resulting in spinal deformities, severe back pain and decreased mobility. Vertebroplasty and kyphoplasty procedures aim to restore the integrity of the deformed vertebral body by injection of biocompatible cement. To date, there have been no long-term studies of the bone-cement interaction in this setting. A reliable large animal model of vertebral osteoporosis would be useful to fully characterise the disease process, to assess potential treatment regimens and to investigate the biocompatibility of bone cements used in kyphoplasty and vertebroplasty. The aim of this pilot study was to develop such a model with ovariectomy, low calcium diet and continuous steroid treatment. Methods: To induce osteoporosis, ten lactating ewes (mean age 8 years) were ovariectomised, injected weekly with 9 mg dexamethasone (Dexafort, Intervet, Australia) and fed low calcium diet. Weekly serum samples were taken to quantify generalised bone resorption (Type 1 collagen C-telopeptide [CTX], ‚-Cross Laps assay, Roche Diagnostics, Australia). Dual-energy X-ray absorptiometry (DEXA, Hologic QDR 1000+, USA) was used to monitor bone mineral density (BMD) in the lumbar spine (L3-L6) after 0, 2, 4, 6 and 9 months of treatment. At each time interval two sheep were killed by barbiturate injection. The entire lumbar spine (L1-L6) was processed for histology, quantitative histomorphometry, mechanical testing and micro-CT (computed tomography). Results: CTX levels increased rapidly after two months (p< 0.05). Baseline BMD in the lumbar spine (0.87±0.06 g/cm2) decreased by 16.9±3.8% or 2.72 standard deviations (p< 0.001) after nine months of treatment. Structural parameters of cancellous bone also showed osteoporotic change. Trabecular bone volume of L2, L3 and L6 vertebrae (pooled) progressively decreased from 24.9±1.2% at two months to 16.5±0.47% at nine months (p< 0.05). Trabecular thickness decreased from 0.14±0.01mm to 0.09±0.01mm, (p< 0.05) and trabecular spacing increased from 0.42±0.03mm to 0.47±0.02mm in the same period. The compressive load at which the L1 vertebrae failed decreased by 39.4% after 9 months. Discussion: This pilot study has demonstrated by DEXA, cancellous bone histomorphometry and mechanical testing, significant bone loss in the sheep lumbar spine up to nine months after ovariectomy and continuous steroid treatment. Assuming that the baseline BMD is representative of mature sheep, the changes in the lumbar spine could be interpreted as osteoporotic. Vertebral bone loss did not reach levels that would result in fracture. However, further work is underway using higher steroid doses to accelerate bone loss. This experimental model will be used to assess aspects of osteoporosis in general and vertebral augmentation procedures in particular


Bone & Joint 360
Vol. 8, Issue 1 | Pages 34 - 36
1 Feb 2019