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1.
Osteoarthritis Cartilage ; 21(6): 796-805, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23499673

ABSTRACT

OBJECTIVE: Changes in T1ρ and T2 magnetic resonance relaxation times have been associated with articular cartilage degeneration, but similar relationships for meniscal tissue have not been extensively investigated. This work examined relationships between T1ρ and T2 measurements and biochemical and mechanical properties across regions of degenerate human menisci. DESIGN: Average T1ρ and T2 relaxation times were determined for nine regions each of seven medial and 13 lateral menisci from 14 total knee replacement patients. Sulfated glycosaminoglycan (sGAG), collagen and water contents were measured for each region. Biomechanical measurements of equilibrium compressive, dynamic compressive and dynamic shear moduli were made for anterior, central and posterior regions. RESULTS: T1ρ and T2 times showed similar regional patterns, with longer relaxation times in the (radially) middle region compared to the inner and outer regions. Pooled over all regions, T1ρ and T2 times showed strong correlations both with one another and with water content. Correlations with biochemical content varied depending on normalization to wet or dry mass, and both imaging parameters showed stronger correlations with collagen compared to sGAG content. Mechanical properties displayed moderate inverse correlations with increasing T1ρ and T2 times and water content. CONCLUSION: Both T1ρ and T2 relaxation times correlated strongly with water content and moderately with mechanical properties in osteoarthritic menisci, but not as strongly with sGAG or collagen contents alone. While the ability of magnetic resonance imaging (MRI) to detect early osteoarthritic changes remains the subject of investigation, these results suggest that T1ρ and T2 relaxation times have limited ability to detect compositional variations in degenerate menisci.


Subject(s)
Cartilage, Articular/pathology , Magnetic Resonance Imaging/methods , Menisci, Tibial/pathology , Aged , Body Water/metabolism , Cartilage, Articular/chemistry , Collagen/metabolism , Female , Glycosaminoglycans/metabolism , Humans , Male , Menisci, Tibial/chemistry , Middle Aged
2.
J Exp Med ; 192(5): 761-8, 2000 Sep 04.
Article in English | MEDLINE | ID: mdl-10974041

ABSTRACT

The immune system has evolved specialized cellular and molecular mechanisms for targeting and regulating immune responses at epithelial surfaces. Here we show that small intestinal intraepithelial lymphocytes and lamina propria lymphocytes migrate to thymus-expressed chemokine (TECK). This attraction is mediated by CC chemokine receptor (CCR)9, a chemoattractant receptor expressed at high levels by essentially all CD4(+) and CD8(+) T lymphocytes in the small intestine. Only a small subset of lymphocytes in the colon are CCR9(+), and lymphocytes from other tissues including tonsils, lung, inflamed liver, normal or inflamed skin, inflamed synovium and synovial fluid, breast milk, and seminal fluid are universally CCR9(-). TECK expression is also restricted to the small intestine: immunohistochemistry reveals that intense anti-TECK reactivity characterizes crypt epithelium in the jejunum and ileum, but not in other epithelia of the digestive tract (including stomach and colon), skin, lung, or salivary gland. These results imply a restricted role for lymphocyte CCR9 and its ligand TECK in the small intestine, and provide the first evidence for distinctive mechanisms of lymphocyte recruitment that may permit functional specialization of immune responses in different segments of the gastrointestinal tract. Selective expression of chemokines by differentiated epithelium may represent an important mechanism for targeting and specialization of immune responses.


Subject(s)
Chemokines, CC/analysis , Intestinal Mucosa/immunology , Intestine, Small/immunology , Receptors, Chemokine/analysis , Animals , Chemokines, CC/physiology , Humans , Mice , Organ Specificity , Receptors, CCR , Receptors, Chemokine/physiology , T-Lymphocytes/chemistry
3.
Bone Joint J ; 101-B(6_Supple_B): 37-44, 2019 06.
Article in English | MEDLINE | ID: mdl-31146559

ABSTRACT

AIMS: Patients may present with concurrent symptomatic osteoarthritis (OA) of the hip and degenerative disorders of the lumbar spine, with surgical treatment being indicated for both. Whether arthroplasty of the hip or spinal surgery should be performed first remains uncertain. MATERIALS AND METHODS: Clinical scenarios were devised for a survey asking the preferred order of surgery and the rationale for this decision for five fictional patients with both OA of the hip and degenerative lumbar disorders. These were symptomatic OA of the hip and: 1) lumbar spinal stenosis with neurological claudication; 2) lumbar degenerative spondylolisthesis with leg pain; 3) lumbar disc herniation with leg weakness; 4) lumbar scoliosis with back pain; and 5) thoracolumbar disc herniation with myelopathy. This survey was sent to 110 members of The Hip Society and 101 members of the Scoliosis Research Society. The choices of the surgeons were compared among scenarios and between surgical specialties using the chi-squared test. The free-text comments were analyzed using text-mining. RESULTS: Responses were received from 51 hip surgeons (46%) and 37 spine surgeons (37%). The percentages of hip surgeons recommending 'hip first' differed significantly among scenarios: 59% for scenario 1; 73% for scenario 2; 47% for scenario 3; 47% for scenario 4; and 10% for scenario 5 (p < 0.001). The percentages of spine surgeons recommending 'hip first' were 49% for scenario 1; 70% for scenario 2; 19% for scenario 3; 78% for scenario 4; and 0% for scenario 5. There were significant differences between the groups for scenarios 3 (more hip surgeons recommended 'hip first'; p = 0.012) and 4 (more hip surgeons recommended 'spine first'; p = 0.006). CONCLUSION: In patients with coexistent OA of the hip and degenerative disorders of the spine, the question of 'hip or spinal surgery first' elicits relatively consistent answers in some clinical scenarios, but remains controversial in others, even for experienced surgeons. The nature of neurological symptoms can influence surgeons' decision-making. Cite this article: Bone Joint J 2019;101-B(6 Supple B):37-44.


Subject(s)
Lumbar Vertebrae/surgery , Osteoarthritis, Hip/surgery , Spinal Diseases/surgery , Clinical Competence/standards , Clinical Decision-Making , Humans , Orthopedic Surgeons/standards , Orthopedic Surgeons/statistics & numerical data , Osteoarthritis, Hip/complications , Practice Patterns, Physicians'/statistics & numerical data , Residence Characteristics , Spinal Diseases/complications , United States
4.
Bone Joint Res ; 8(2): 41-48, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30915209

ABSTRACT

OBJECTIVES: Intra-articular injections of local anaesthetics (LA), glucocorticoids (GC), or hyaluronic acid (HA) are used to treat osteoarthritis (OA). Contrast agents (CA) are needed to prove successful intra-articular injection or aspiration, or to visualize articular structures dynamically during fluoroscopy. Tranexamic acid (TA) is used to control haemostasis and prevent excessive intra-articular bleeding. Despite their common usage, little is known about the cytotoxicity of common drugs injected into joints. Thus, the aim of our study was to investigate the effects of LA, GC, HA, CA, and TA on the viability of primary human chondrocytes and tenocytes in vitro. METHODS: Human chondrocytes and tenocytes were cultured in a medium with three different drug dilutions (1:2; 1:10; 1:100). The following drugs were used to investigate cytotoxicity: lidocaine hydrochloride 1%; bupivacaine 0.5%; triamcinolone acetonide; dexamethasone 21-palmitate; TA; iodine contrast media; HA; and distilled water. Normal saline served as a control. After an incubation period of 24 hours, cell numbers and morphology were assessed. RESULTS: Using LA or GC, especially triamcinolone acetonide, a dilution of 1:100 resulted in only a moderate reduction of viability, while a dilution of 1:10 showed significantly fewer cell counts. TA and CA reduced viability significantly at a dilution of 1:2. Higher dilutions did not affect viability. Notably, HA showed no effects of cytotoxicity in all drug dilutions. CONCLUSION: The toxicity of common intra-articular injectable drugs, assessed by cell viability, is mainly dependent on the dilution of the drug being tested. LA are particularly toxic, whereas HA did not affect cell viability.Cite this article: P. Busse, C. Vater, M. Stiehler, J. Nowotny, P. Kasten, H. Bretschneider, S. B. Goodman, M. Gelinsky, S. Zwingenberger. Cytotoxicity of drugs injected into joints in orthopaedics. Bone Joint Res 2019;8:41-48. DOI: 10.1302/2046-3758.82.BJR-2018-0099.R1.

5.
Bone Joint J ; 100-B(1): 28-32, 2018 01.
Article in English | MEDLINE | ID: mdl-29305447

ABSTRACT

AIMS: Many case reports and small studies have suggested that cobalt ions are a potential cause of cardiac complications, specifically cardiomyopathy, after metal-on-metal (MoM) total hip arthroplasty (THA). The impact of metal ions on the incidence of cardiac disease after MoM THA has not been evaluated in large studies. The aim of this study was to compare the rate of onset of new cardiac symptoms in patients who have undergone MoM THA with those who have undergone metal-on-polyethylene (MoP) THA. PATIENTS AND METHODS: Data were extracted from the Standard Analytics Files database for patients who underwent MoM THA between 2005 and 2012. Bearing surface was selected using International Classification of Diseases ninth revision codes. Patients with a minimum five-year follow-up were selected. An age and gender-matched cohort of patients who underwent MoP THA served as a comparison group. New diagnoses of cardiac disease were collected during the follow-up period. Comorbidities and demographics were identified and routine descriptive statistics were used. RESULTS: We identified 29 483 patients who underwent MoM THA and 24 175 matched patients who underwent MoP THA. Both groups had a mean Charlson comorbidity index score of 4. There were no statistically significant differences in 30 of 31 pre-existing comorbidities. Patients undergoing MoM THA had a slightly lower incidence of cardiac failure compared with those undergoing MoP THA at three years (6.60% versus 7.06%, odds ratio (OR) 0.93, 95% confidence interval (CI) 0.87 to 0.99) and four years (8.73% versus 9.49%, OR 0.91, 95% CI 0.86 to 0.97) postoperatively, with no difference in the incidence of new cardiac failure in between the groups at five years. There was no statistically significant difference in the incidence of arrhythmia, myocardial infarction and cardiomyopathy at any time between the two groups. CONCLUSION: MoM THA is not associated with cardiac complications. Initial reports may have represented individual instances of cardiac disease in patients with a failing MoM articulation rather than an emerging epidemiological trend. Cite this article: Bone Joint J 2018;100-B:28-32.


Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Heart Diseases/etiology , Hip Prosthesis/adverse effects , Metal-on-Metal Joint Prostheses/adverse effects , Aged , Aged, 80 and over , Arthroplasty, Replacement, Hip/instrumentation , Comorbidity , Databases, Factual , Female , Heart Diseases/epidemiology , Humans , Incidence , Male , Middle Aged , Polyethylene , Prosthesis Design , Prosthesis Failure/etiology , United States/epidemiology
6.
J Biomed Mater Res A ; 81(2): 310-6, 2007 May.
Article in English | MEDLINE | ID: mdl-17120215

ABSTRACT

The effects of an oral p38 mitogen-activated protein kinase (MAPK) inhibitor and polyethylene particles separately and together on tissue differentiation in the bone harvest chamber (BHC) in rabbits over a 3-week treatment period were investigated. The harvested tissue was analyzed histomorphometrically for markers of bone formation (percentage of bone area), osteoblasts (alkaline phosphatase staining), and osteoclasts (CD51, the alpha chain of the vitronectin receptor). Polyethylene particles decreased the percentage of bone ingrowth and staining for alkaline phosphatase. The p38 MAPK inhibitor alone decreased alkaline phosphatase staining. When the oral p38 MAPK inhibitor was given and the chamber contained polyethylene particles, there was a suppression of bone ingrowth and alkaline phosphatase staining. In contrast to oral non-steroidal anti-inflammatory drugs (NSAIDs) and local Interleukin-1 receptor antagonist (IL-1ra) administration, the oral p38 MAPK inhibitor alone did not suppress bone formation when given during the initial phase of tissue differentiation. Particle-induced inflammation and the foreign body reaction were not curtailed when the p38 MAPK inhibitor was given simultaneously with particles. Additional experiments are needed to establish the efficacy of p38 MAPK inhibitor administration on mitigating an established inflammatory and foreign body reaction that parallels the clinical situation more closely.


Subject(s)
Osseointegration/drug effects , Protein Kinase Inhibitors/pharmacology , p38 Mitogen-Activated Protein Kinases/antagonists & inhibitors , Administration, Oral , Animals , Biocompatible Materials , Diffusion Chambers, Culture , Joint Prosthesis/adverse effects , Male , Materials Testing , Osteolysis/etiology , Osteolysis/prevention & control , Polyethylenes , Prosthesis Failure , Protein Kinase Inhibitors/administration & dosage , Rabbits , Tibia/pathology , Tibia/surgery , Tissue Engineering
7.
Bone Joint J ; 99-B(5): 601-606, 2017 05.
Article in English | MEDLINE | ID: mdl-28455468

ABSTRACT

AIMS: The stability of cementless acetabular components is an important factor for surgical planning in the treatment of patients with pelvic osteolysis after total hip arthroplasty (THA). However, the methods for determining the stability of the acetabular component from pre-operative radiographs remain controversial. Our aim was to develop a scoring system to help in the assessment of the stability of the acetabular component under these circumstances. PATIENTS AND METHODS: The new scoring system is based on the mechanism of failure of these components and the location of the osteolytic lesion, according to the DeLee and Charnley classification. Each zone is evaluated and scored separately. The sum of the individual scores from the three zones is reported as a total score with a maximum of 10 points. The study involved 96 revision procedures which were undertaken for wear or osteolysis in 91 patients between July 2002 and December 2012. Pre-operative anteroposterior pelvic radiographs and Judet views were reviewed. The stability of the acetabular component was confirmed intra-operatively. RESULTS: Intra-operatively, it was found that 64 components were well-fixed and 32 were loose. Mean total scores in the well-fixed and loose components were 2.9 (0 to 7) and 7.2 (1 to 10), respectively (p < 0.001). In hips with a low score (0 to 2), the component was only loose in one of 33 hips (3%). The incidence of loosening increased with increasing scores: in those with scores of 3 and 4, two of 19 components (10.5%) were loose; in hips with scores of 5 and 6, eight of 19 components (44.5%) were loose; in hips with scores of 7 or 8, 13 of 17 components (70.6%) were loose; and for hips with scores of 9 and 10, nine of nine components (100%) were loose. Receiver-operating-characteristic curve analysis demonstrated very good accuracy (area under the curve = 0.90, p < 0.001). The optimal cutoff point was a score of ≥ 5 with a sensitivity of 0.79, and a specificity of 0.87. CONCLUSION: There was a strong correlation between the scoring system and the probability of loosening of a cementless acetabular component. This scoring system provides a clinically useful tool for pre-operative planning, and the evaluation of the outcome of revision surgery for patients with loosening of a cementless acetabular component in the presence of osteolysis. Cite this article: Bone Joint J 2017;99-B:601-6.


Subject(s)
Acetabulum/diagnostic imaging , Arthroplasty, Replacement, Hip/methods , Osteolysis/diagnostic imaging , Acetabulum/surgery , Adult , Aged , Aged, 80 and over , Arthroplasty, Replacement, Hip/adverse effects , Arthroplasty, Replacement, Hip/instrumentation , Bone Cements , Cementation , Female , Hip Prosthesis/adverse effects , Humans , Intraoperative Care/methods , Male , Middle Aged , Osteolysis/etiology , Osteolysis/surgery , Prosthesis Failure/etiology , ROC Curve , Radiography , Reoperation/methods , Severity of Illness Index
8.
Bone Joint J ; 99-B(4): 440-444, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28385931

ABSTRACT

AIMS: Modular or custom-made femoral components have been preferred for total hip arthroplasty (THA) in patients with a history of Perthes' disease because of the distortion in the anatomy of the proximal femur. However, it has not been established whether a monobloc cementless stem will fit the distorted proximal femur or whether the results of the procedure are satisfactory in this group of patients. PATIENTS AND METHODS: We reviewed 68 consecutive patients who had undergone THA for childhood Perthes' disease between June 2003 and December 2008. There were 35 men and 33 women with a mean age of 48 years (16 to 73) at the time of index arthroplasty. Their mean body mass index was 24.4 (18.3 to 32.9). Of the 68 hips, 32 were classified as Stulberg class III and 36 as class IV. The mean pre-operative shortening of the affected leg was 17.2 mm (5 to 34). The minimum follow-up was five years (mean 8.5 years; 5.2 to 10). RESULTS: An intra-operative calcar fracture occurred in eight hips (11.8%) and was successfully treated by cerclage wiring. The mean stem version was 14.6° (-2.3 to 30; standard deviation (sd) 7.3). The mean acetabular component abduction was 40.2° (23.7 to 56.0; sd 6.5) and the mean anteversion 28.3° (6.4 to 43.0; sd 7.6), respectively. The mean follow-up was 8.5 years (5.2 to 10). No dislocations occurred and no hips were revised during the course of the study. At final follow-up, the mean Harris Hip Score was 91 points (59 to 100) and the mean University of California, Los Angeles activity score was 3.2 (2 to 8). CONCLUSION: Monobloc cementless stems reliably restore the anatomy in Perthes' disease at THA without the need for custom-made or modular implants. Cite this article: Bone Joint J 2017;99-B:440-444.


Subject(s)
Arthroplasty, Replacement, Hip/methods , Hip Prosthesis , Legg-Calve-Perthes Disease/surgery , Osteoarthritis, Hip/surgery , Adolescent , Adult , Aged , Cementation , Female , Femur/surgery , Hip Joint/diagnostic imaging , Humans , Legg-Calve-Perthes Disease/complications , Legg-Calve-Perthes Disease/diagnostic imaging , Male , Middle Aged , Osteoarthritis, Hip/diagnostic imaging , Osteoarthritis, Hip/etiology , Prosthesis Design , Radiography , Retrospective Studies , Treatment Outcome , Young Adult
9.
Adv Protein Chem Struct Biol ; 107: 117-154, 2017.
Article in English | MEDLINE | ID: mdl-28215222

ABSTRACT

Inflammation is a defensive mechanism for pathogen clearance and maintaining tissue homeostasis. In the skeletal system, inflammation is closely associated with many bone disorders including fractures, nonunions, periprosthetic osteolysis (bone loss around orthopedic implants), and osteoporosis. Acute inflammation is a critical step for proper bone-healing and bone-remodeling processes. On the other hand, chronic inflammation with excessive proinflammatory cytokines disrupts the balance of skeletal homeostasis involving osteoblastic (bone formation) and osteoclastic (bone resorption) activities. NF-κB is a transcriptional factor that regulates the inflammatory response and bone-remodeling processes in both bone-forming and bone-resorption cells. In vitro and in vivo evidences suggest that NF-κB is an important potential therapeutic target for inflammation-associated bone disorders by modulating inflammation and bone-remodeling process simultaneously. The challenges of NF-κB-targeting therapy in bone disorders include: (1) the complexity of canonical and noncanonical NF-κB pathways; (2) the fundamental roles of NF-κB-mediated signaling for bone regeneration at earlier phases of tissue damage and acute inflammation; and (3) the potential toxic effects on nontargeted cells such as lymphocytes. Recent developments of novel inhibitors with differential approaches to modulate NF-κB activity, and the controlled release (local) or bone-targeting drug delivery (systemic) strategies, have largely increased the translational application of NF-κB therapy in bone disorders. Taken together, temporal modulation of NF-κB pathways with the combination of recent advanced bone-targeting drug delivery techniques is a highly translational strategy to reestablish homeostasis in the skeletal system.


Subject(s)
Bone Diseases/drug therapy , Inflammation/complications , NF-kappa B/antagonists & inhibitors , Bone Diseases/etiology , Bone Remodeling , Humans , NF-kappa B/metabolism , Signal Transduction
10.
Bone Joint J ; 99-B(10): 1267-1279, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28963146

ABSTRACT

Non-traumatic osteonecrosis of the femoral head is a potentially devastating condition, the prevalence of which is increasing. Many joint-preserving forms of treatment, both medical and surgical, have been developed in an attempt to slow or reverse its progression, as it usually affects young patients. However, it is important to evaluate the best evidence that is available for the many forms of treatment considering the variation in the demographics of the patients, the methodology and the outcomes in the studies that have been published, so that it can be used effectively. The purpose of this review, therefore, was to provide an up-to-date, evidence-based guide to the management, both non-operative and operative, of non-traumatic osteonecrosis of the femoral head. Cite this article: Bone Joint J 2017;99-B:1267-79.


Subject(s)
Evidence-Based Medicine , Femur Head Necrosis/surgery , Orthopedic Procedures/standards , Practice Guidelines as Topic , Humans
11.
Biomaterials ; 27(21): 3882-7, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16540164

ABSTRACT

The pro-angiogenic cytokine vascular endothelial growth factor (VEGF) has been implicated in periprosthetic osteolysis and subsequent aseptic loosening of implants following total hip arthroplasty (THA). The goal of this study was to investigate whether increased VEGF at the bone-implant interface is secondary to a greater number of VEGF-producing cells or to increased VEGF production by individual cells. Real time polymerase chain reaction (RT-PCR) techniques were used to assess the expression of VEGF mRNA (isoforms 121, 165, 189) in periprosthetic tissues from revision THAs. Immunofluorescence was used to determine both differences in overall cellularity and in VEGF-producing cell type (macrophages, fibroblasts, endothelial cells) between patients with periprosthetic osteolysis (OL) and a control group undergoing primary THA for osteoarthritis (OA). Quantitative analysis of VEGF release in periprosthetic membranes via RT-PCR demonstrated no significant difference in the per-cell mRNA production of VEGF isoforms 121 165, or 189 between OL and OA patient groups. Immunofluorescence showed both higher cellularity and higher overall VEGF expression in the OL group. Immunofluorescence also showed a significant increase in macrophages in the OL group, but no significant difference in the proportion of fibroblasts or endothelial cells between the OL and OA groups. Co-localization of CD68+ and CD11b+ macrophage fluorescent signals with VEGF signal was greater in the OL group than in the OA group. Our results demonstrate that increased VEGF in OL periprosthetic tissue compared to OA synovium is correlated to increased numbers of VEGF-producing CD68+ and CD11b+ macrophages. Impact statement: Aseptic loosening, caused in large part by OL, remains the major cause of failed THAs leading to revision surgery. At the bone-implant interface, we found increased numbers of macrophages-cellular mediators of OL-and increased VEGF expression. VEGF may be a possible target for therapeutic intervention in mitigating OL.


Subject(s)
Osteoarthritis/metabolism , Osteoarthritis/pathology , Osteolysis/metabolism , Osteolysis/pathology , Prosthesis-Related Infections/metabolism , Prosthesis-Related Infections/pathology , Vascular Endothelial Growth Factor A/metabolism , Aged , Aged, 80 and over , Cells, Cultured , Female , Hip Prosthesis/adverse effects , Humans , Male , Middle Aged , Osteoarthritis/etiology , Osteoarthritis/surgery , Osteolysis/etiology , Prosthesis-Related Infections/etiology
12.
J Biomed Mater Res A ; 77(3): 512-7, 2006 Jun 01.
Article in English | MEDLINE | ID: mdl-16482550

ABSTRACT

Wear particles generated following total joint arthroplasty interact with cells at the periprosthetic margin and induce an inflammatory response that contributes to osteolysis, aseptic loosening, and implant failure. This study examined the long-term effects of particles from two commonly implanted materials, titanium (Ti) and polymethylmethacrylate (PMMA), on cell viability and metabolism over a 21-day time course, using the human osteoblast-like cell line MG-63. Addition of particles was not associated with increased cell death or nitric oxide production at the particle concentration chosen. Collagen production was increased with exposure to titanium particles, whereas alkaline phosphatase and osteocalcin expression remained unchanged following exposure to both types of particles. The data show that titanium but not PMMA particles shifts bone cell metabolism to preferentially produce fibrous tissue rather than bone.


Subject(s)
Biocompatible Materials , Osteoblasts , Polymethyl Methacrylate , Titanium , Cell Line , Humans , Osteoblasts/cytology , Osteoblasts/metabolism
13.
J Biomed Mater Res A ; 79(3): 740-6, 2006 Dec 01.
Article in English | MEDLINE | ID: mdl-16988970

ABSTRACT

Excessive polyethylene wear particles from joint replacements may lead to periprosthetic osteolysis and loosening. Nonsteroidal anti-inflammatory drugs (NSAIDs) decrease fracture healing and bone ingrowth. We hypothesized that continuous local infusion of OP-1 (BMP-7) would increase local bone formation in the presence of two different adverse stimuli, polyethylene particles, and an oral NSAID. The Drug Test Chamber (DTC) was implanted in the proximal tibia of mature rabbits. The tissue growing into the chamber was exposed to OP-1 solution (110 ng/day), which was infused via an osmotic pump. Infusion of OP-1 alone for 6 weeks enhanced local bone formation in the chamber by 80% (p < 0.05) over infusion of carrier alone. In the presence of polyethylene particles, infusion of OP-1 increased local bone formation by 38% (p < 0.05) over treatment with particles and carrier. Oral administration of NSAID reduced local bone formation by 58% (p < 0.05); this suppressive effect caused by NSAIDS was completely reversed by the infusion of OP-1 (p < 0.05). These findings underline a potential role for local treatment with OP-1 to increase bone formation in the presence of potentially adverse stimuli such as polyethylene wear particles or NSAID use.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Bone Morphogenetic Proteins/pharmacology , Osteogenesis/drug effects , Transforming Growth Factor beta/pharmacology , Alkaline Phosphatase/metabolism , Animals , Bone Morphogenetic Protein 7 , Polyethylene , Rabbits
14.
Malays Orthop J ; 9(1): 44-46, 2015 Mar.
Article in English | MEDLINE | ID: mdl-28435598

ABSTRACT

A 59 year old man who had undergone left total knee arthroplasty in 2008 presented with a 5 month history of left knee pain and persistent swelling. Workup for infection was negative and the patient was suspected to be suffering from particle disease and chronic synovitis. Imaging revealed an internally rotated tibial component. Intraoperative findings revealed extensive polyethylene wear with resultant metalon- metal articulation, soft tissue metallosis and a pseudotumor like mass at the posterolateral aspect of the popliteal fossa. This was extensively debrided and revision knee arthroplasty was performed. Suboptimal component alignment can lead to localized high loading, wear and metallosis, which in this case resulted in the formation of a pseudotumor.

15.
Hum Pathol ; 15(1): 91-3, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6693116

ABSTRACT

A 53-year-old man had the monomelic form of Ollier's disease, which resulted in deformity of the left leg. The patient was otherwise well until pain and increasing size of the left thigh led him to seek treatment. Biopsy revealed chondrosarcomatous transformation in the distal left femur. Hip disarticulation was performed. This case is unusual in that multiple foci of chondrosarcomatous transformation at various stages of development were present throughout the left femur, tibia, and fibula.


Subject(s)
Bone Neoplasms/etiology , Chondrosarcoma/etiology , Osteochondrodysplasias/complications , Amputation, Surgical , Bone Neoplasms/surgery , Chondrosarcoma/surgery , Femur , Fibula , Hip Joint/surgery , Humans , Male , Middle Aged , Tibia
16.
Biomaterials ; 14(10): 723-8, 1993 Aug.
Article in English | MEDLINE | ID: mdl-8218720

ABSTRACT

The interfacial membrane harvested from failed joint replacements contains particulate debris from the materials used for the implant. To define the tissue response to particulate titanium alloy and hydroxyapatite (HA) alone, 16 mature New Zealand white rabbits were divided into 2 groups of 8 rabbits. Using sterile technique, a drill hole was placed anteromedially in the tibia, 1 cm distal to the knee joint bilaterally. The marrow was scooped out and 0.25 mg of either titanium alloy particles or HA particles were inserted in the right tibia. The titanium alloy particles had a diameter averaging 4.0 +/- 4.4 microns (mean +/- standard deviation) and an aspect ratio (the ratio of the maximum length divided by the maximum width) of 1.84. The HA particles had a diameter of 4.4 +/- 3.3 microns and an aspect ratio of 1.76. The left leg was prepared in a similar fashion, but no biomaterial was implanted. The animals were killed after 16 wk. The harvested tibiae were processed with decalcification and the plastic-embedded sections were subjected to histomorphological analysis. Black titanium alloy particles were present within the bone marrow fat between haematopoietic cells, and within scattered macrophages. The surrounding bone appeared to be unaffected. Within the spongiosa, the HA particles were surrounded by small numbers of mononuclear histiocytes or encased within a shell of new appositional bone. Where HA deposits were exposed to the endosteal aspect of bone, there was scalloping of the surface of the HA in a pattern suggestive of resorption or dissolution of the HA particles.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Durapatite , Foreign-Body Reaction/etiology , Prostheses and Implants/adverse effects , Tibia/pathology , Titanium , Alloys , Animals , Bone Marrow/pathology , Female , Foreign-Body Reaction/pathology , Macrophages , Osteoclasts , Rabbits
17.
Biomaterials ; 14(7): 522-8, 1993 Jun.
Article in English | MEDLINE | ID: mdl-8329525

ABSTRACT

Fourteen mature New Zealand white female rabbits had a unilateral cemented, stemmed, titanium, condylar-type tibial hemiarthroplasty, using an anteromedial arthrotomy of the right knee. The articular cartilage and minimal bone were resected. There were two prosthetic groups of seven animals each: a well-fixed, non-loose group and a loose group. In the non-loose group, the implant was inserted into the cement bed and axially compressed until the PMMA had cured. In the loose group, the same volume of cement was allowed to cure on the implant ex vivo; the prosthesis was then implanted to ensure that it was loose fitting. Radiographs were performed at zero and 3 months and graded for new lucent lines. Histological analysis was performed using undecalcified coronal sections, surface stained with toluidine blue with the prosthesis in situ, and the cement mantle preserved. Back-scattered electron microscopy was also performed. The mean cumulative grading of new lucent lines was 0.3 +/- 0.1 for the non-loose group and 2.2 +/- 0.4 for the loose group (P < 0.005). Non-loose prostheses were surrounded by a thin fibrous membrane or bone. Loose prostheses were surrounded by a thicker, fibrous tissue layer, containing histiocytes and giant cells which were more prevalent around cement particles, especially near the prosthetic tip. These findings parallel the histology found at cemented prosthetic interfaces in humans. The results of this study suggest that the fibrohistiocytic membrane commonly found around loose cemented implants may be the result of, rather than the cause of, the loosening process.


Subject(s)
Bone Cements , Knee Joint/diagnostic imaging , Knee Prosthesis/adverse effects , Tibia/surgery , Animals , Female , Knee Joint/surgery , Microscopy, Electron, Scanning/methods , Models, Biological , Prosthesis Failure , Rabbits , Radiography , Tibia/diagnostic imaging
18.
Biomaterials ; 15(11): 889-93, 1994 Sep.
Article in English | MEDLINE | ID: mdl-7833435

ABSTRACT

Short, daily periods of externally-applied strain have been shown previously to affect the differentiation of mesenchymal tissue. In this study, we examine the effects of discontinuing a strain protocol known to produce primarily fibrous tissue rather than bone in the micromotion chamber (MC). Five MCs were inserted into the proximal tibial metaphysis of mature male New Zealand white rabbits. The MC has a 1 x 1 x 5 mm pore for tissue ingrowth. After osseointegration of the fixed outer cylinder of the chamber, the inner movable core was manipulated for 40 cycles per day delivered at a rate of 1 Hertz ('40'). This provided motion at the interface between the cylinder and the core. The tissue in the pore was harvested after 3 wks. The MCs were then manipulated at 40 cycles per day for 3 wks and then the manipulations were discontinued for 3 additional wks ('40 + 0'); the contents of the chamber were harvested after 6 wks. Finally, the chambers were left without manipulation ('0') and harvested after 3 wks. Histological sections from unmoved chambers ('0') contained extensive trabecular bone, embedded in a fibrovascular stroma. The '40' specimens were composed primarily of longitudinally orientated fibrous tissue. The '40 + 0' specimens were similar histologically to the '0' specimens. The amount of bone ingrowth expressed as a percentage of the area of the section averaged 37 +/- 6 (mean +/- standard error of the mean) for the '0' specimens, 20 +/- 2 for the '40' specimens and 37 +/- 7 for the '40 + 0' specimens.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Fracture Healing/physiology , Osseointegration/physiology , Animals , Biocompatible Materials , Biomechanical Phenomena , Male , Materials Testing , Motion , Prostheses and Implants , Rabbits , Stress, Mechanical , Tibia/injuries , Tibia/pathology , Tibia/physiology
19.
Biomaterials ; 12(2): 194-6, 1991 Mar.
Article in English | MEDLINE | ID: mdl-1878453

ABSTRACT

Twenty-nine mature New Zealand white, female rabbits were divided into four groups. Using sterile technique, a 6 mm drill hole was made in the tibia 1 cm distal to the knee joint. The marrow was scooped out underneath the hole. The right tibia received Simplex particulate cement polymer (PMMA) (groups 1 and 2) or polyethylene particles (UHMWP) (groups 3 and 4). The left leg functioned as a prepared but non-implanted control. All animals were fed a standard diet; those in groups 1 and 3 received plain water, while groups 2 and 4 drank water in which sodium naproxen was dissolved (1.375 mg/ml). Animals were killed after 16 wk. The implant area was harvested and grown in tissue culture. The cumulative collection of tissue culture supernatants over 3 d was assayed for prostaglandin E2 (PGE2) via radioimmunoassay. PGE2 production was significantly higher in the membrane harvested from the right side containing particulate cement with no sodium naproxen (group 1) compared with controls (P less than 0.05). The ratio of PGE2 values for the right divided by the left side yielded higher values in group 1, compared with groups 2, 3 or 4 (P less than 0.01). Previous studies have suggested that particulate debris and PGE2 production are associated with arthroplasty loosening. This experiment has demonstrated that PGE2 production by the membrane surrounding particulate debris can be suppressed by the administration of oral sodium naproxen. Because non-steroidal anti-inflammatory drugs are known to inhibit prostaglandin synthesis in man, these agents may prove useful in retarding the bone loss associated with early prosthetic loosening.


Subject(s)
Biocompatible Materials , Bone Cements , Methylmethacrylates , Naproxen/pharmacology , Polyethylenes , Prostheses and Implants , Synovial Membrane/drug effects , Animals , Dinoprostone/biosynthesis , Female , Knee Joint , Molecular Weight , Prosthesis Failure , Rabbits , Surface Properties , Synovial Membrane/metabolism , Tibia
20.
Biomaterials ; 17(20): 1943-7, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8894085

ABSTRACT

Wear debris has been implicated in the pathogenesis of loosening and osteolysis of total joint replacements by stimulating a foreign body and chronic inflammatory reaction capable of bone resorption. Whether increasing concentrations of wear particles have an adverse biological effect on bone has not been elucidated. We performed a histomorphological and semi-quantitative morphometric analysis of the reaction of bone to different concentrations of phagocytosable particles of high-density polyethylene (HDPE) and titanium 6-aluminium 4-vanadium alloy (Ti-6Al-4V) implanted in the rabbit tibia. The Ti-6Al-4V particles had a diameter of 4.0 +/- 4.4 microns (mean +/- SD); the HDPE particles averaged 4.7 +/- 2.1 microns. Suspensions of 10(6)-10(9) particles per ml were mixed in saline, sterilized, and introduced through a drill hole into the proximal tibia of 30 mature female rabbits. Controls included drilled, but non-implantable limbs. The animals were killed at 16 weeks and histological sections were made of the implant area. Histomorphological assessment was carried out using an interactive image analysis system. The parameters assessed included the presence of histiocytes, foreign body giant cells and inflammatory cells, the location and number of particles, the presence of haematopoeitic elements, fat or necrosis of the marrow, whether healing of the cortical window had taken place, and whether there was evidence of formation or resorption of bone by the periosteum, cortex and marrow. A semi-quantitative rating system was employed. Phagocytosable particles of Ti-6Al-4V and HDPE, in concentrations of 10(6)-10(9) particles per ml, evoked a histiocytic reaction without extensive fibrosis, necrosis or granuloma formation. This reaction occurred without disturbing the normal repair processes of bone formation and resorption to the surgical insult. A clear dose-response effect on the histological parameters assessed in this study was not noted. Using the present model, by 16 weeks, a similar "one time' particle load could be accommodated. The ongoing generation of particulate debris over a more extended period of time might be necessary before the remodelling processes of bone would be disturbed.


Subject(s)
Aluminum/metabolism , Phagocytosis/drug effects , Polyethylenes/metabolism , Titanium/metabolism , Vanadium/metabolism , Alloys , Aluminum/adverse effects , Animals , Biocompatible Materials , Bone Development/drug effects , Bone Marrow/drug effects , Bone Marrow/metabolism , Bone Resorption/chemically induced , Dose-Response Relationship, Drug , Female , Molecular Weight , Periosteum/drug effects , Periosteum/metabolism , Polyethylenes/adverse effects , Prostheses and Implants/adverse effects , Rabbits , Tibia/metabolism , Titanium/adverse effects , Vanadium/adverse effects
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