Advertisement for orthosearch.org.uk
Results 1 - 23 of 23
Results per page:
The Journal of Bone & Joint Surgery British Volume
Vol. 78-B, Issue 5 | Pages 838 - 839
1 Sep 1996
Chimento GF Finger S Barrack RL

We reviewed 194 revision arthroplasties of the hip and knee performed over a ten-year period. The results of intraoperative Gram staining were available in 169 (87%). Thirty-two were found to be infected (11 hips and 21 knees) and 137 had no evidence of infection. Intraoperative Gram staining was negative in all 169 cases. The method therefore had a sensitivity of 0% for detecting infection. We conclude that the absence of organisms on intraoperative Gram staining during revision arthroplasty does not confirm the absence of infection


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 10 | Pages 1439 - 1444
1 Oct 2005
Davies AP Sood A Lewis AC Newson R Learmonth ID Case CP

Previous research has shown an increase in chromosomal aberrations in patients with worn implants. The type of aberration depended on the type of metal alloy in the prosthesis. We have investigated the metal-specific difference in the level of DNA damage (DNA stand breaks and alkali labile sites) induced by culturing human fibroblasts in synovial fluid retrieved at revision arthroplasty. All six samples from revision cobalt-chromium metal-on-metal and four of six samples from cobalt-chromium metal-on-polyethylene prostheses caused DNA damage. By contrast, none of six samples from revision stainless-steel metal-on-polyethylene prostheses caused significant damage. Samples of cobalt-chromium alloy left to corrode in phosphate-buffered saline also caused DNA damage and this depended on a synergistic effect between the cobalt and chromium ions. Our results further emphasise that epidemiological studies of orthopaedic implants should take account of the type of metal alloy used


The Journal of Bone & Joint Surgery British Volume
Vol. 83-B, Issue 7 | Pages 1075 - 1081
1 Sep 2001
Doherty AT Howell RT Ellis LA Bisbinas I Learmonth ID Newson R Case CP

The long-term biological effects of wear debris are unknown. We have investigated whether there is any evidence of cumulative mutagenic damage in peripheral blood lymphocytes of patients undergoing revision arthroplasty of predominantly metal-on-plastic total hip replacements compared with those at primary arthroplasty. There was a threefold increase in aneuploidy and a twofold increase in chromosomal translocations which could not be explained by the confounding variables of smoking, gender, age and diagnostic radiographs. In the patients with TiVaAl prostheses there was a fivefold increase in aneuploidy but no increase in chromosomal translocations. By contrast, in patients with cobalt-chrome prostheses there was a 2.5-fold increase in aneuploidy and a 3.5-fold increase in chromosomal translocations. In six patients with stainless-steel prostheses there was no increase in either aneuploidy or chromosomal translocations. Our results suggest that future epidemiological studies of the putative long-term risks of joint replacement should take into account the type of alloy used in the prosthesis


The Journal of Bone & Joint Surgery British Volume
Vol. 81-B, Issue 3 | Pages 552 - 554
1 May 1999
Crawford R Puddle B Hunt N Athanasou NA

We reviewed histologically the incidence and pathogenesis of the deposition of calcium pyrophosphate dihydrate (CPPD) crystals in the pseudocapsule, femoral and acetabular membranes and periprosthetic tissue at revision of 789 cases of failed total hip replacement. In 13, periprosthetic tissues were found to have deposits of CPPD crystals in areas of cartilaginous metaplasia; four also showed evidence of localised deposition of amyloid. None of the patients had a history of chondrocalcinosis in the hip or other joints. Cartilaginous metaplasia and other changes in periprosthetic tissues may predispose to the deposition of CPPD and associated localised amyloid.


Bone & Joint 360
Vol. 13, Issue 2 | Pages 47 - 49
1 Apr 2024
Burden EG Krause T Evans JP Whitehouse MR Evans JT


The Journal of Bone & Joint Surgery British Volume
Vol. 82-B, Issue 5 | Pages 748 - 754
1 Jul 2000
Case CP Langkamer VG Lock RJ Perry MJ Palmer MR Kemp AJ

We compared the peripheral blood and periprosthetic tissues of 53 patients at revision arthroplasty with those of 30 patients at primary arthroplasty to determine whether there is a systemic difference in lymphocytes in patients with worn hip implants. The absolute number and relative proportion of lymphocytes bearing CD2, CD3, CD4, CD8, CD16, CD19, HLA-DR, kappa and lambda antigens were compared with the levels of IL-1β, IL-6 and PGE. 2. in the pseudosynovial membrane as well as with a semiquantitative estimate of metal and polyethylene particles, necrosis and chronic inflammation and the total concentration of metals within the periprosthetic tissues. There was a significant increase in the relative proportion of CD2-positive T-cells and CD16-positive natural killer cells in the peripheral blood at revision arthroplasty compared with primary arthroplasty and an increased proportion of CD8-positive T-cells and a decreased ratio of CD4 to CD8 (helper inducer/suppressor cytotoxic cells). Three control patients, who went on to have revision surgery, had values at primary arthroplasty which were similar to those of patients at the time of revision surgery. These differences did not correlate with the local concentration of metal, plastic or cement or inflammatory response or the type of prosthesis. An inverse correlation was noted between the necrosis in the periprosthetic tissue and both the local production of IL-6 and the absolute numbers of T-cells in peripheral blood. We conclude that there may be several cell-mediated systemic immune responses to aseptic loosening, at least one of which may be directly related to events in the periprosthetic tissues. We cannot exclude the possibility that the changes in the proportion of CD8-positive cells reflected a predisposition, rather than a reaction, to loosening of the implant


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 6 | Pages 832 - 836
1 Jun 2006
Barker R Takahashi T Toms A Gregson P Kuiper JH

The use of impaction bone grafting during revision arthroplasty of the hip in the presence of cortical defects has a high risk of post-operative fracture. Our laboratory study addressed the effect of extramedullary augmentation and length of femoral stem on the initial stability of the prosthesis and the risk of fracture. Cortical defects in plastic femora were repaired using either surgical mesh without extramedullary augmentation, mesh with a strut graft or mesh with a plate. After bone impaction, standard or long-stem Exeter prostheses were inserted, which were tested by cyclical loading while measuring defect strain and migration of the stem. Compared with standard stems without extramedullary augmentation, defect strains were 31% lower with longer stems, 43% lower with a plate and 50% lower with a strut graft. Combining extramedullary augmentation with a long stem showed little additional benefit (p = 0.67). The type of repair did not affect the initial stability. Our results support the use of impaction bone grafting and extramedullary augmentation of diaphyseal defects after mesh containment


The Journal of Bone & Joint Surgery British Volume
Vol. 81-B, Issue 1 | Pages 118 - 124
1 Jan 1999
Brewster NT Gillespie WJ Howie CR Madabhushi SPG Usmani AS Fairbairn DR

In impaction grafting of contained bone defects after revision joint arthroplasty the graft behaves as a friable aggregate and its resistance to complex forces depends on grading, normal load and compaction. Bone mills in current use produce a distribution of particle sizes more uniform than is desirable for maximising resistance to shear stresses. We have performed experiments in vitro using morsellised allograft bone from the femoral head which have shown that its mechanical properties improve with increasing normal load and with increasing shear strains (strain hardening). The mechanical strength also increases with increasing compaction energy, and with the addition of bioglass particles to make good the deficiency in small and very small fragments. Donor femoral heads may be milled while frozen without affecting the profile of the particle size. Osteoporotic femoral heads provide a similar grading of sizes, although fewer particles are obtained from each specimen. Our findings have implications for current practice and for the future development of materials and techniques


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 3 | Pages 436 - 439
1 Apr 2003
Nogler M Lass-Flörl C Wimmer C Mayr E Bach C Ogon M

Instruments used in surgery which rotate or vibrate at a high frequency can produce potentially contaminated aerosols. Such tools are in use in cemented hip revision arthroplasties. We aimed to measure the extent of the environmental and body contamination caused by an ultrasound device and a high-speed cutter. On a human cadaver we carried out a complete surgical procedure including draping and simulated blood flow contaminated with Staphylococcus aureus (ATCC 12600). After cemented total hip arthroplasty, we undertook repeated extractions of cement using either an ultrasound device or a high-speed cutter. Surveillance cultures detected any environmental and body contamination of the surgical team. Environmental contamination was present in an area of 6 x 8 m for both devices. The concentration of contamination was lower for the ultrasound device. Both the ultrasound and the high-speed cutter contaminated all members of the surgical team. The devices tested produced aerosols which covered the whole operating theatre and all personnel present during the procedure. In contaminated and infected patients, infectious agents may be present in these aerosols. We therefore recommend the introduction of effective measures to control infection and thorough disinfection of the operating theatre after such procedures


The Journal of Bone & Joint Surgery British Volume
Vol. 78-B, Issue 2 | Pages 270 - 275
1 Mar 1996
Hooten JP Engh CA Heekin RD Vinh TN

Two acetabula which contained large bone allografts introduced at revision arthroplasty were obtained at post-mortem. The allografts had been placed in superior defects to support cementless acetabular components, and both hips were functioning well at the time of death. Clinical radiographs demonstrated apparent healing of graft to host bone, no graft collapse and stability of the acetabular components. Microscopic examination of sections through these specimens showed that the bulk allografts were encapsulated in fibrous tissue. Vascularity was increased at the host-graft interface, but there was limited evidence of bone union between the graft and the host. In the few areas where union had occurred, revascularisation extended no more than 2 mm beyond the graft-host interface. Within the body of the graft, the acellular matrix of trabecular bone maintained structural integrity up to 48 months after surgery. In areas where the allograft was adjacent to an implant, there was fibrous tissue orientated parallel to the implant surface. The acetabulum which contained a porous-coated component showed evidence of bone growth into the porous surface where it was in contact with viable host bone. No ingrowth occurred in areas where the porous coating was in contact with the graft. Although the grafts were functioning well, allograft revascularisation and remodelling were minimal, and the radiological appearance of healing did not correlate with histological findings


The Journal of Bone & Joint Surgery British Volume
Vol. 78-B, Issue 6 | Pages 973 - 978
1 Nov 1996
Malkani AL Voor MJ Fee KA Bates CS

We have tested the axial and torsional stability of femoral components after revision arthroplasty in a cadaver model, using impacted morsellised cancellous graft and cement. Each one of six matched pairs of fresh frozen human femora had either a primary or a revision prosthesis cemented in place. For the ‘revision’ experiments, all cancellous bone was removed from the proximal femur which was then over-reamed to create a smooth-walled cortical shell. An MTS servohydraulic test frame was used to apply axial and torsional loads to each specimen through the prosthetic femoral heads with the femur submerged in isotonic saline solution at 37°C. The mean subsidence was 0.27 ± 0.17 mm for the primary and 0.52 ± 0.30 mm for the revision groups. The difference was statistically significant (p < 0.025), but the mean subsidence was < 1 mm in both groups. The mean maximum torque before failure was 42.9 ± 26.9 N-m for the primary and 34.8± 20.7 N-m for the revision groups. This difference was not statistically significant (p > 0.015). Based on our results we suggest that revision of the femoral component using morsellised cancellous graft followed by cementing with a collarless prosthesis with a polished tapered stem restores the integrity of the proximal femur and provides immediate stability of the implant


Bone & Joint Research
Vol. 7, Issue 1 | Pages 12 - 19
1 Jan 2018
Janz V Schoon J Morgenstern C Preininger B Reinke S Duda G Breitbach A Perka CF Geissler S

Objectives

The objective of this study was to develop a test for the rapid (within 25 minutes) intraoperative detection of bacteria from synovial fluid to diagnose periprosthetic joint infection (PJI).

Methods

The 16s rDNA test combines a polymerase chain reaction (PCR) for amplification of 16s rDNA with a lateral flow immunoassay in one fully automated system. The synovial fluid of 77 patients undergoing joint aspiration or primary or revision total hip or knee surgery was prospectively collected. The cohort was divided into a proof-of-principle cohort (n = 17) and a validation cohort (n = 60). Using the proof-of-principle cohort, an optimal cut-off for the discrimination between PJI and non-PJI samples was determined. PJI was defined as detection of the same bacterial species in a minimum of two microbiological samples, positive histology, and presence of a sinus tract or intra-articular pus.


Bone & Joint Research
Vol. 5, Issue 9 | Pages 403 - 411
1 Sep 2016
Mrosek EH Chung H Fitzsimmons JS O’Driscoll SW Reinholz GG Schagemann JC

Objectives

We sought to determine if a durable bilayer implant composed of trabecular metal with autologous periosteum on top would be suitable to reconstitute large osteochondral defects. This design would allow for secure implant fixation, subsequent integration and remodeling.

Materials and Methods

Adult sheep were randomly assigned to one of three groups (n = 8/group): 1. trabecular metal/periosteal graft (TMPG), 2. trabecular metal (TM), 3. empty defect (ED). Cartilage and bone healing were assessed macroscopically, biochemically (type II collagen, sulfated glycosaminoglycan (sGAG) and double-stranded DNA (dsDNA) content) and histologically.


Bone & Joint Research
Vol. 5, Issue 2 | Pages 26 - 32
1 Feb 2016
Wendling A Mar D Wischmeier N Anderson D McIff T

Objectives

The objective of this study was to determine if combining variations in mixing technique of antibiotic-impregnated polymethylmethacrylate (PMMA) cement with low frequency ultrasound (LFUS) improves antibiotic elution during the initial high phase (Phase I) and subsequent low phase (Phase II) while not diminishing mechanical strength.

Methods

Three batches of vancomycin-loaded PMMA were prepared with different mixing techniques: a standard technique; a delayed technique; and a control without antibiotic. Daily elution samples were analysed using flow injection analysis (FIA). Beginning in Phase II, samples from each mix group were selected randomly to undergo either five, 15, 45, or 0 minutes of LFUS treatment. Elution amounts between LFUS treatments were analysed. Following Phase II, compression testing was done to quantify strength. A-priorit-tests and univariate ANOVAs were used to compare elution and mechanical test results between the two mix groups and the control group.


Bone & Joint Research
Vol. 3, Issue 1 | Pages 14 - 19
1 Jan 2014
James SJ Mirza SB Culliford DJ Taylor PA Carr AJ Arden NK

Aims

Osteoporosis and abnormal bone metabolism may prove to be significant factors influencing the outcome of arthroplasty surgery, predisposing to complications of aseptic loosening and peri-prosthetic fracture. We aimed to investigate baseline bone mineral density (BMD) and bone turnover in patients about to undergo arthroplasty of the hip and knee.

Methods

We prospectively measured bone mineral density of the hip and lumbar spine using dual-energy X-ray absorptiometry (DEXA) scans in a cohort of 194 patients awaiting hip or knee arthroplasty. We also assessed bone turnover using urinary deoxypyridinoline (DPD), a type I collagen crosslink, normalised to creatinine.


Bone & Joint 360
Vol. 3, Issue 3 | Pages 39 - 40
1 Jun 2014
Arastu M


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 2 | Pages 272 - 276
1 Feb 2005
Hendriks JGE Neut D van Horn JR van der Mei HC Busscher HJ

Clinical experience indicates the beneficial effects of antibiotic-loaded bone cement. Although in vitro studies have shown the formation of a biofilm on its surface they have not considered the gap between the cement and the bone. We have investigated bacterial survival in that gap. Samples with gaps 200 μm wide were made of different bone cements. These were stored dry (‘pre-elution’) or submersed in phosphate-buffered saline to simulate the initial release of gentamicin (‘post-elution’). The gaps were subsequently inoculated with bacteria, which had been isolated from infected orthopaedic prostheses and assessed for their sensitivity to gentamicin. Bacterial survival was measured 24 hours after inoculation. All the strains survived in plain cements. In the pre-elution gentamicin-loaded cements only the most gentamicin-resistant strain, CN5115, survived, but in post-elution samples more strains did so, depending on the cement tested. Although high concentrations of gentamicin were demonstrated in the gaps only the gentamicin-sensitive strains were killed. This could explain the increased prevalence of gentamicin-resistant infections which are seen clinically.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 1 | Pages 179 - 185
1 Jan 2010
Väänänen P Pajamäki I Paakkala A Nurmi JT Pajamäki J

We used a biodegradable mesh to convert an acetabular defect into a contained defect in six patients at total hip replacement. Their mean age was 61 years (46 to 69). The mean follow-up was 32 months (19 to 50). Before clinical use, the strength retention and hydrolytic in vitro degradation properties of the implants were studied in the laboratory over a two-year period. A successful clinical outcome was determined by the radiological findings and the Harris hip score.

All the patients had a satisfactory outcome and no mechanical failures or other complications were observed. No protrusion of any of the impacted grafts was observed beyond the mesh. According to our preliminary laboratory and clinical results the biodegradable mesh is suitable for augmenting uncontained acetabular defects in which the primary stability of the implanted acetabular component is provided by the host bone. In the case of defects of the acetabular floor this new application provides a safe method of preventing graft material from protruding excessively into the pelvis and the mesh seems to tolerate bone-impaction grafting in selected patients with primary and revision total hip replacement.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 6 | Pages 821 - 824
1 Jun 2008
Board TN Rooney P Kay PR

In order to investigate the osteoinductive properties of allograft used in impaction grafting and the effect of strain during impaction on these properties, we designed an in vitro experiment to measure strain-related release of bone morphogenetic protein-7 (BMP-7) from fresh-frozen femoral head allograft. A total of 40 10 mm cubes of cancellous bone were cut from ten samples of fresh-frozen femoral head. The marrow was removed from the cubes and the baseline concentrations of BMP-7 were measured. Specimens from each femoral head were allocated to four groups and subjected to different compressive strains with a material testing machine, after which BMP-7 activity was reassessed. It was present in all groups. There was a linear increase of 102.1 pg/g (95% confidence interval 68.6 to 135.6) BMP-7 for each 10% increase in strain. At 80% strain the mean concentration of BMP-7 released (830.3 pg/g bone) was approximately four times that released at 20% strain. Activity of BMP-7 in fresh-frozen allograft has not previously been demonstrated. This study shows that the freezing and storage of femoral heads allows some maintenance of biological activity, and that impaction grafting provides a source of osteoinductive bone for remodelling.

We have shown that BMP-7 is released from fresh-frozen femoral head cancellous bone in proportion to the strain applied to the bone. This suggests that the impaction process itself may contribute to the biological process of remodelling and bony incorporation.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 4 | Pages 535 - 541
1 Apr 2008
Pendegrass CJ Sundar S Oddy MJ Cannon SR Briggs T Blunn GW

We used an in vivo model to assess the use of an autogenous cancellous bone block and marrow graft for augmenting tendon reattachment to metallic implants. We hypothesised that augmentation of the tendon-implant interface with a bone block would enable retention of the graft on the implant surface, enhance biological integration, and result in more consistent functional outcomes compared with previously reported morcellised graft augmentation techniques.

A significant improvement in functional weight-bearing was observed between six and 12 weeks. The significant increase in ground reaction force through the operated limb between six and 12 weeks was greater than that reported previously with morcellised graft augmented reconstructions. Histological appearance and collagen fibre orientation with bone block augmentation more closely resembled that of an intact enthesis compared with the morcellised grafting technique. Bone block augmentation of tendon-implant interfaces results in more reliable functional and histological outcomes, with a return to pre-operative levels of weight-bearing by 24 weeks.


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 9 | Pages 1245 - 1251
1 Sep 2006
Pendegrass CJ Oddy MJ Sundar S Cannon SR Goodship AE Blunn GW

We examined the mechanical properties of Vicryl (polyglactin 910) mesh in vitro and assessed its use in vivo as a novel biomaterial to attach tendon to a hydroxyapatite-coated metal implant, the interface of which was augmented with autogenous bone and marrow graft. This was compared with tendon re-attachment using a compressive clamp device in an identical animal model. Two- and four-ply sleeves of Vicryl mesh tested to failure under tension reached 5.13% and 28.35% of the normal ovine patellar tendon, respectively. Four-ply sleeves supported gait in an ovine model with 67.05% weight-bearing through the operated limb at 12 weeks, without evidence of mechanical failure.

Mesh fibres were visible at six weeks but had been completely resorbed by 12 weeks, with no evidence of chronic inflammation. The tendon-implant neoenthesis was predominantly an indirect type, with tendon attached to the bone-hydroxyapatite surface by perforating collagen fibres.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 3 | Pages 421 - 425
1 Mar 2005
Blom AW Cunningham JL Hughes G Lawes TJ Smith N Blunn G Learmonth ID Goodship AE

This study investigates the use of porous biphasic ceramics as graft extenders in impaction grafting of the femur during revision hip surgery.

Impaction grafting of the femur was performed in four groups of sheep. Group one received pure allograft, group two 50% allograft and 50% BoneSave, group three 50% allograft and 50% BoneSave type 2 and group four 10% allograft and 90% BoneSave as the graft material. Function was assessed using an index of pre- and post-operative peak vertical ground reaction force ratios. Changes in bone mineral density were measured by dual energy X ray absorptiometry (DEXA) scanning. Loosening and subsidence were assessed radiographically and by histological examination of the explanted specimens.

There was no statistically significant difference between the four groups after 18 months of unrestricted functional loading for all outcome measures.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 11 | Pages 1568 - 1574
1 Nov 2005
Day RE Megson S Wood D

Allograft bone is widely used in orthopaedic surgery, but peri-operative infection of the graft remains a common and disastrous complication. The efficacy of systemic prophylactic antibiotics is unproven, and since the graft is avascular it is likely that levels of antibiotic in the graft are low.

Using an electrical potential to accelerate diffusion of antibiotics into allograft bone, high levels were achieved in specimens of both sheep and human allograft. In human bone these ranged from 187.1 mg/kg in endosteal (sd 15.7) to 124.6 (sd 46.2) in periosteal bone for gentamicin and 31.9 (sd 8.9) in endosteal and 2.9 (sd 1.1) in periosteal bone for flucloxacillin. The antibiotics remained active against bacteria in vitro after iontophoresis and continued to elute from the allograft for up to two weeks.

Structural allograft can be supplemented directly with antibiotics using iontophoresis. The technique is simple and inexpensive and offers a potential means of reducing the rate of peri-operative infection in allograft surgery. Iontophoresis into allograft bone may also be applicable to other therapeutic compounds.