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The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 1 | Pages 169 - 172
1 Jan 1998
Jorn LP Fridén T Ryd L Lindstrand A

We obtained simultaneous measurements of sagittal knee laxity in 12 consecutive patients after reconstruction of the anterior cruciate ligament (ACL), using the Stryker laxity tester and radiostereometric analysis (RSA). The mean anteroposterior (AP) displacement when a 90 N load was applied in both directions was 5.3 ± 2.7 mm with RSA and 9.8 ± 1.6 mm with the external device (p < 0.001). The corresponding measurements at a load of 180 N were 5.7 ± 2.4 mm and 13.8 ± 3.7 mm, respectively (p < 0.001). More than 50% of the sagittal knee movement, as measured by the external device at a load of 180 N, was not true femorotibial displacement of the joint but was due to soft-tissue deformation


Bone & Joint Research
Vol. 7, Issue 8 | Pages 511 - 516
1 Aug 2018
Beverly M Mellon S Kennedy JA Murray DW

Objectives. We studied subchondral intraosseous pressure (IOP) in an animal model during loading, and with vascular occlusion. We explored bone compartmentalization by saline injection. Materials and Methods. Needles were placed in the femoral condyle and proximal tibia of five anaesthetized rabbits and connected to pressure recorders. The limb was loaded with and without proximal vascular occlusion. An additional subject had simultaneous triple recordings at the femoral head, femoral condyle and proximal tibia. In a further subject, saline injections at three sites were carried out in turn. Results. Loading alone caused a rise in subchondral IOP from 11.7 mmHg (. sd. 7.1) to 17.9 mmHg (. sd. 8.1; p < 0.0002). During arterial occlusion, IOP fell to 5.3 mmHg (. sd. 4.1), then with loading there was a small rise to 7.6 mmHg (. sd. 4.5; p < 0.002). During venous occlusion, IOP rose to 20.2 mmHg (. sd. 5.8), and with loading there was a further rise to 26.3 mmHg (. sd. 6.3; p < 0.003). The effects were present at three different sites along the limb simultaneously. Saline injections showed pressure transmitted throughout the length of the femur but not across the knee joint. Conclusion. This is the first study to report changes in IOP in vivo during loading and with combinations of vascular occlusion and loading. Intraosseous pressure is not a constant. It is reduced during proximal arterial occlusion and increased with proximal venous occlusion. Whatever the perfusion state, in vivo load is transferred partly by hydraulic pressure. We propose that joints act as hydraulic pressure barriers. An understanding of subchondral physiology may be important in understanding osteoarthritis and other bone diseases. Cite this article: M. Beverly, S. Mellon, J. A. Kennedy, D. W. Murray. Intraosseous pressure during loading and with vascular occlusion in an animal model. Bone Joint Res 2018;7:511–516. DOI: 10.1302/2046-3758.78.BJR-2017-0343.R2


Bone & Joint Research
Vol. 5, Issue 12 | Pages 602 - 609
1 Dec 2016
Muto T Kokubu T Mifune Y Inui A Sakata R Harada Y Takase F Kurosaka M

Objectives. Triamcinolone acetonide (TA) is widely used for the treatment of rotator cuff injury because of its anti-inflammatory properties. However, TA can also produce deleterious effects such as tendon degeneration or rupture. These harmful effects could be prevented by the addition of platelet-rich plasma (PRP), however, the anti-inflammatory and anti-degenerative effects of the combined use of TA and PRP have not yet been made clear. The objective of this study was to determine how the combination of TA and PRP might influence the inflammation and degeneration of the rotator cuff by examining rotator cuff-derived cells induced by interleukin (IL)-1ß. Methods. Rotator cuff-derived cells were seeded under inflammatory stimulation conditions (with serum-free medium with 1 ng/ml IL-1ß for three hours), and then cultured in different media: serum-free (control group), serum-free + TA (0.1mg/ml) (TA group), serum-free + 10% PRP (PRP group), and serum-free + TA (0.1mg/ml) + 10% PRP (TA+PRP group). Cell morphology, cell viability, and expression of inflammatory and degenerative mediators were assessed. Results. Exposure to TA significantly decreased cell viability and changed the cell morphology; these effects were prevented by the simultaneous administration of PRP. Compared with the control group, expression levels of inflammatory genes and reactive oxygen species production were reduced in the TA, PRP, and TA+PRP groups. PRP significantly decreased the expression levels of degenerative marker genes. Conclusions. The combination of TA plus PRP exerts anti-inflammatory and anti-degenerative effects on rotator cuff-derived cells stimulated by IL-1ß. This combination has the potential to relieve the symptoms of rotator cuff injury. Cite this article: T. Muto, T. Kokubu, Y. Mifune, A. Inui, R. Sakata, Y. Harada, F. Takase, M. Kurosaka. Effects of platelet-rich plasma and triamcinolone acetonide on interleukin-1ß-stimulated human rotator cuff-derived cells. Bone Joint Res 2016;5:602–609. DOI: 10.1302/2046-3758.512.2000582


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 11 | Pages 1528 - 1533
1 Nov 2007
Jeffcote B Nicholls R Schirm A Kuster MS

Achieving deep flexion after total knee replacement remains a challenge. In this study we compared the soft-tissue tension and tibiofemoral force in a mobile-bearing posterior cruciate ligament-sacrificing total knee replacement, using equal flexion and extension gaps, and with the gaps increased by 2 mm each. The tests were conducted during passive movement in five cadaver knees, and measurements of strain were made simultaneously in the collateral ligaments. The tibiofemoral force was measured using a customised mini-force plate in the tibial tray. Measurements of collateral ligament strain were not very sensitive to changes in the gap ratio, but tibiofemoral force measurements were. Tibiofemoral force was decreased by a mean of 40% (. sd. 10.7) after 90° of knee flexion when the flexion gap was increased by 2 mm. Increasing the extension gap by 2 mm affected the force only in full extension. Because increasing the range of flexion after total knee replacement beyond 110° is a widely-held goal, small increases in the flexion gap warrant further investigation


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 5 | Pages 682 - 687
1 May 2006
Kanazawa T Soejima T Murakami H Inoue T Katouda M Nagata K

We studied bone-tendon healing using immunohistochemical methods in a rabbit model. Reconstruction of the anterior cruciate ligament was undertaken using semitendinosus tendon in 20 rabbits. Immunohistochemical evaluations were performed at one, two, four and eight weeks after the operation. The expression of CD31, RAM-11, VEGF, b-FGF, S-100 protein and collagen I, II and III in the bone-tendon interface was very similar to that in the endochondral ossification. Some of the type-III collagen in the outer layer of the graft, which was deposited at a very early phase after the operation, was believed to have matured into Sharpey-like fibres. However, remodelling of the tendon grafted into the bone tunnel was significantly delayed when compared with this ossification process. To promote healing, we believe that it is necessary to accelerate remodelling of the tendon, simultaneously with the augmentation of the ossification


The Journal of Bone & Joint Surgery British Volume
Vol. 91-B, Issue 1 | Pages 131 - 137
1 Jan 2009
Boraiah S Dyke JP Hettrich C Parker RJ Miller A Helfet D Lorich D

In spite of extensive accounts describing the blood supply to the femoral head, the prediction of avascular necrosis is elusive. Current opinion emphasises the contributions of the superior retinacular artery but may not explain the clinical outcome in many situations, including intramedullary nailing of the femur and resurfacing of the hip. We considered that significant additional contribution to the vascularity of the femoral head may exist. A total of 14 fresh-frozen hips were dissected and the medial circumflex femoral artery was cannulated in the femoral triangle. On the test side, this vessel was ligated, with the femoral head receiving its blood supply from the inferior vincular artery alone. Gadolinium contrast-enhanced MRI was then performed simultaneously on both control and test specimens. Polyurethane was injected, and gross dissection of the specimens was performed to confirm the extraosseous anatomy and the injection of contrast. The inferior vincular artery was found in every specimen and had a significant contribution to the vascularity of the femoral head. The head was divided into four quadrants: medial (0), superior (1), lateral (2) and inferior (3). In our study specimens the inferior vincular artery contributed a mean of 56% (25% to 90%) of blood flow in quadrant 0, 34% (14% to 80%) of quadrant 1, 37% (18% to 48%) of quadrant 2 and 68% (20% to 98%) in quadrant 3. Extensive intra-osseous anastomoses existed between the superior retinacular arteries, the inferior vincular artery and the subfoveal plexus


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 2 | Pages 288 - 291
1 Mar 2003
Sampathkumar K Jeyam M Evans CE Andrew JG

Aseptic loosening of orthopaedic implants is usually attributed to the action of wear debris from the prosthesis. Recent studies, however, have also implicated physical pressures in the joint as a further cause of loosening. We have examined the role of both wear debris and pressure on the secretion of two chemokines, MIP-1α and MCP-1, together with M-CSF and PGE2, by human macrophages in vitro. The results show that pressure alone stimulated the secretion of more M-CSF and PGE. 2. when compared with control cultures. Particles alone stimulated the secretion of M-CSF and PGE. 2. , when compared with unstimulated control cultures, but did not stimulate the secretion of the two chemokines. Exposure of macrophages to both stimuli simultaneously had no synergistic effect on the secretion of the chemokines, but both M-CSF and PGE. 2. were increased in a synergistic manner. Our findings suggest that pressure may be an initiating factor for the recruitment of cells into the periprosthetic tissue


The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 6 | Pages 1073 - 1078
1 Nov 1998
Tucker SK Taylor BA

In normal, physiological circumstances there is ample room in the spinal canal to accommodate the spinal cord. Our study aimed to identify the degree of compromise of the spinal canal which could be anticipated in various atlantoaxial pathological states. We examined paired atlas and axis vertebrae using high-definition radiography and simultaneous photography in both normal and simulated pathological orientations in order to measure the resultant dimension of the spinal canal and its percentage occlusion. At the extreme of physiological axial rotation (47°) the spinal canal is reduced to 61% of its cross-sectional area in neutral rotation. The spinal cord is thus safe from compromise. Atlantoaxial subluxation of up to 9 mm reduces the area of the spinal canal, in neutral rotation, to 60% with no cord compromise. Any rotation is, however, likely to cause cord compression. The mechanism of fixation in atlantoaxial rotatory subluxation could be explained by bony interlocking of the facet joint, reproducible in dry bones


The Journal of Bone & Joint Surgery British Volume
Vol. 85-B, Issue 8 | Pages 1182 - 1189
1 Nov 2003
Hacking SA Harvey EJ Tanzer M Krygier JJ Bobyn JD

We designed an in vivo study to determine if the superimposition of a microtexture on the surface of sintered titanium beads affected the extent of bone ingrowth. Cylindrical titanium intramedullary implants were coated with titanium beads to form a porous finish using commercial sintering techniques. A control group of implants was left in the as-sintered condition. The test group was etched in a boiling acidic solution to create an irregular surface over the entire porous coating. Six experimental dogs underwent simultaneous bilateral femoral intramedullary implantation of a control implant and an acid etched implant. At 12 weeks, the implants were harvested in situ and the femora processed for undecalcified, histological examination. Eight transverse serial sections for each implant were analysed by backscattered electron microscopy and the extent of bone ingrowth was quantified by computer-aided image analysis. The extent of bone ingrowth into the control implants was 15.8% while the extent of bone ingrowth into the etched implants was 25.3%, a difference of 60% that was statistically significant. These results are consistent with other research that documents the positive effect of microtextured surfaces on bone formation at an implant surface. The acid etching process developed for this study represents a simple method for enhancing the potential of commonly available porous coatings for biological fixation


The Journal of Bone & Joint Surgery British Volume
Vol. 83-B, Issue 8 | Pages 1182 - 1190
1 Nov 2001
Minovic A Milosev I Pisot V Cör A Antolic V

We analysed revised Mathys isoelastic polyacetal femoral stems with stainless-steel heads and polyethylene acetabular cups from eight patients in order to differentiate various types of particle of wear debris. Loosening of isoelastic femoral stems is associated with the formation of polyacetal wear particles as well as those of polyethylene and metal. All three types of particle were isolated simultaneously by tissue digestion followed by sucrose gradient centrifugation. Polyacetal particles were either elongated, ranging from 10 to 150 μm in size, or shred-like and up to 100 μm in size. Polyethylene particles were elongated or granules, and were typically submicron or micronsized. Polyacetal and polyethylene polymer particles were differentiated by the presence of BaSO. 4. , which is added as a radiopaque agent to polyacetal but not to polyethylene. This was easily detectable by back-scattered SEM analysis and verified by energy dispersive x-ray analysis. Two types of foreign-body giant cell (FBGC) were recognised in the histological specimens. Extremely large FBGCs with irregular polygonal particles showing an uneven, spotty birefringence in polarised light were ascribed to polyacetal debris. Smaller FBGCs with slender elongated particles shining uniformly brightly in polarisation were related to polyethylene. Mononucleated histiocytes containing both types of particle were also present. Our findings offer a better understanding of the processes involved in the loosening of polyacetal stems and indicate why the idea of ‘isoelasticity’ proved to be unsuccessful in clinical practice


The Journal of Bone & Joint Surgery British Volume
Vol. 80-B, Issue 2 | Pages 365 - 369
1 Mar 1998
Abraham P Leftheriotis G Saumet JL

Chronic compartment syndrome (CCS) is usually considered to be due to ischaemia of muscle. We have attempted to use the direct measurement of muscle blood flow for diagnosis since the assessment of intracompartmental pressure does not provide accurate knowledge of the vascular state. We recorded simultaneously continuous measurements of the laser Doppler flow (LDF) in muscle and the intracompartment pressure (ICP) after exercise in seven patients with CCS, and in seven control subjects. The mean ICP was 74.1 ± 4.4 mmHg in CCS patients and 24.2 ± 3.4 mmHg in control subjects one minute after exercise, decreasing to 34.6 ± 2.3 mmHg and 15.0 ± 1.6 mmHg at 20 min, respectively. The LDF was 0.80 ± 0.11 arbitrary units (AU) in control subjects and 1.09 ± 0.14 AU in CCS patients one minute after exercise, and 0.41 ± 0.11 AU and 0.27 ± 0.04 AU, respectively, at the end of the recovery period. The ICP showed a progressive decrease over time in both groups. The LDF decreased sharply during the first minutes of recovery in control subjects, but in patients with CCS there was a delayed hyperaemic peak with blood flow reaching 0.84 ± 0.10 AU at nine minutes as against 0.33 ± 0 .06 AU for control subjects (p < 0.01). The ICP increased in both control subjects and CCS patients after exercise with no clear cut-off point between the groups. By contrast, changes in muscle blood flow over time were clearly different between control subjects and patients with CCS. For this reason, LDF should be investigated further as a technique for the diagnosis of CCS


The Journal of Bone & Joint Surgery British Volume
Vol. 83-B, Issue 5 | Pages 742 - 750
1 Jul 2001
Kim Y Kim J Cho S

We have reviewed 70 patients with bilateral simultaneous total hip arthroplasties to determine the rate of failure and to compare polyethylene wear and osteolysis between an implant with a cobalt-chrome head and Hylamer liner with that of a zirconia head and Hylamer liner. The mean thickness of the polyethylene liner was 11.0 mm (8.8 to 12.2) in the hip with a zirconia head and 10.7 mm (8.8 to 12.2) in that with a cobalt-chrome head. At follow-up at 6.4 years no acetabular or femoral component had been revised for aseptic loosening and no acetabular or femoral component was loose according to radiological criteria in both the cemented and cementless groups. The mean rate of linear wear and annual wear rate were highest in the 22 mm zirconia femoral head (1.25 mm (SD 1.05) and 0.21 mm (SD 0.18), respectively) and lowest in the 22 mm cobalt-chrome femoral head (0.70 mm (SD 0.39) and 0.12 mm (SD 0.07), respectively). The mean volumetric wear was highest in the 28 mm zirconia femoral head (730.79 mm. 3. ) and lowest in the 22 mm cobalt-chrome femoral head (264.67 mm. 3. ), but if the results were compared by size of the femoral head and type of material there was no statistical difference (p > 0.05). Sequential measurements of annual wear showed that the zirconia femoral head had a relatively higher rate of penetration than the cobalt-chrome head over the first three years; thereafter the rate of wear was reduced and compared favourably with that of cobalt-chrome heads. There was a statistically significant relationship between the wear of the polyethylene liner and the age of the patient, male gender and the degree of abduction angle of the cup, but not diagnosis, weight, hip score, range of movement, or amount of anteversion. Osteolysis was identified on both sides of the acetabulum in six patients (9%). Of 12 hips with acetabular osteolysis, six had a 28 mm cobalt-chrome femoral head and the remaining six a 28 mm zirconia head. Osteolysis was observed in zones 1A and 7A of the femur in two hips (3%) with a 28 mm zirconia head (cemented hip) and in four (6%) with a 28 mm cobalt-chrome femoral head (cementless hip). Our findings suggest that although the performance of a zirconia femoral head with a Hylamer liner was not statistically different from that of a cobalt-chrome femoral head and Hylamer liner, there was a trend for the zirconia head to be worse than the cobalt-chrome femoral head


Objectives

Platelet-rich fibrin matrix (PRFM) has been proved to enhance tenocyte proliferation but has mixed results when used during rotator cuff repair. The optimal PRFM preparation protocol should be determined before clinical application. To screen the best PRFM to each individual’s tenocytes effectively, small-diameter culture wells should be used to increase variables. The gelling effect of PRFM will occur when small-diameter culture wells are used. A co-culture device should be designed to avoid this effect.

Methods

Tenocytes harvested during rotator cuff repair and blood from a healthy volunteer were used. Tenocytes were seeded in 96-, 24-, 12-, and six-well plates and co-culture devices. Appropriate volumes of PRFM, according to the surface area of each culture well, were treated with tenocytes for seven days. The co-culture device was designed to avoid the gelling effect that occurred in the small-diameter culture well. Cell proliferation was analyzed by water soluble tetrazolium-1 (WST-1) bioassay.


Bone & Joint Research
Vol. 6, Issue 10 | Pages 572 - 576
1 Oct 2017
Wang W Huang S Hou W Liu Y Fan Q He A Wen Y Hao J Guo X Zhang F

Objectives

Several genome-wide association studies (GWAS) of bone mineral density (BMD) have successfully identified multiple susceptibility genes, yet isolated susceptibility genes are often difficult to interpret biologically. The aim of this study was to unravel the genetic background of BMD at pathway level, by integrating BMD GWAS data with genome-wide expression quantitative trait loci (eQTLs) and methylation quantitative trait loci (meQTLs) data

Method

We employed the GWAS datasets of BMD from the Genetic Factors for Osteoporosis Consortium (GEFOS), analysing patients’ BMD. The areas studied included 32 735 femoral necks, 28 498 lumbar spines, and 8143 forearms. Genome-wide eQTLs (containing 923 021 eQTLs) and meQTLs (containing 683 152 unique methylation sites with local meQTLs) data sets were collected from recently published studies. Gene scores were first calculated by summary data-based Mendelian randomisation (SMR) software and meQTL-aligned GWAS results. Gene set enrichment analysis (GSEA) was then applied to identify BMD-associated gene sets with a predefined significance level of 0.05.


Bone & Joint Research
Vol. 6, Issue 5 | Pages 315 - 322
1 May 2017
Martinez-Perez M Perez-Jorge C Lozano D Portal-Nuñez S Perez-Tanoira R Conde A Arenas MA Hernandez-Lopez JM de Damborenea JJ Gomez-Barrena E Esbrit P Esteban J

Objectives

Implant-related infection is one of the most devastating complications in orthopaedic surgery. Many surface and/or material modifications have been developed in order to minimise this problem; however, most of the in vitro studies did not evaluate bacterial adhesion in the presence of eukaryotic cells, as stated by the ‘race for the surface’ theory. Moreover, the adherence of numerous clinical strains with different initial concentrations has not been studied.

Methods

We describe a method for the study of bacterial adherence in the presence of preosteoblastic cells. For this purpose we mixed different concentrations of bacterial cells from collection and clinical strains of staphylococci isolated from implant-related infections with preosteoblastic cells, and analysed the minimal concentration of bacteria able to colonise the surface of the material with image analysis.


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. 6, Issue 3 | Pages 137 - 143
1 Mar 2017
Cho HS Park YK Gupta S Yoon C Han I Kim H Choi H Hong J

Objectives

We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model.

Methods

We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice.


Bone & Joint Research
Vol. 5, Issue 1 | Pages 1 - 10
1 Jan 2016
Burghardt RD Manzotti A Bhave A Paley D Herzenberg JE

Objectives

The purpose of this study was to compare the results and complications of tibial lengthening over an intramedullary nail with treatment using the traditional Ilizarov method.

Methods

In this matched case study, 16 adult patients underwent 19 tibial lengthening over nails (LON) procedures. For the matched case group, 17 patients who underwent 19 Ilizarov tibial lengthenings were retrospectively matched to the LON group.


Bone & Joint Research
Vol. 6, Issue 9 | Pages 542 - 549
1 Sep 2017
Arnold M Zhao S Ma S Giuliani F Hansen U Cobb JP Abel RL Boughton O

Objectives

Microindentation has the potential to measure the stiffness of an individual patient’s bone. Bone stiffness plays a crucial role in the press-fit stability of orthopaedic implants. Arming surgeons with accurate bone stiffness information may reduce surgical complications including periprosthetic fractures. The question addressed with this systematic review is whether microindentation can accurately measure cortical bone stiffness.

Methods

A systematic review of all English language articles using a keyword search was undertaken using Medline, Embase, PubMed, Scopus and Cochrane databases. Studies that only used nanoindentation, cancellous bone or animal tissue were excluded.


Bone & Joint Research
Vol. 5, Issue 11 | Pages 560 - 568
1 Nov 2016
Peeters M Huang CL Vonk LA Lu ZF Bank RA Helder MN Doulabi BZ

Objectives

Studies which consider the molecular mechanisms of degeneration and regeneration of cartilaginous tissues are seriously hampered by problematic ribonucleic acid (RNA) isolations due to low cell density and the dense, proteoglycan-rich extracellular matrix of cartilage. Proteoglycans tend to co-purify with RNA, they can absorb the full spectrum of UV light and they are potent inhibitors of polymerase chain reaction (PCR). Therefore, the objective of the present study is to compare and optimise different homogenisation methods and RNA isolation kits for an array of cartilaginous tissues.

Materials and Methods

Tissue samples such as the nucleus pulposus (NP), annulus fibrosus (AF), articular cartilage (AC) and meniscus, were collected from goats and homogenised by either the MagNA Lyser or Freezer Mill. RNA of duplicate samples was subsequently isolated by either TRIzol (benchmark), or the RNeasy Lipid Tissue, RNeasy Fibrous Tissue, or Aurum Total RNA Fatty and Fibrous Tissue kits. RNA yield, purity, and integrity were determined and gene expression levels of type II collagen and aggrecan were measured by real-time PCR.