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Bone & Joint Research
Vol. 6, Issue 3 | Pages 162 - 171
1 Mar 2017
Walker JA Ewald TJ Lewallen E Van Wijnen A Hanssen AD Morrey BF Morrey ME Abdel MP Sanchez-Sotelo J

Objectives

Sustained intra-articular delivery of pharmacological agents is an attractive modality but requires use of a safe carrier that would not induce cartilage damage or fibrosis. Collagen scaffolds are widely available and could be used intra-articularly, but no investigation has looked at the safety of collagen scaffolds within synovial joints. The aim of this study was to determine the safety of collagen scaffold implantation in a validated in vivo animal model of knee arthrofibrosis.

Materials and Methods

A total of 96 rabbits were randomly and equally assigned to four different groups: arthrotomy alone; arthrotomy and collagen scaffold placement; contracture surgery; and contracture surgery and collagen scaffold placement. Animals were killed in equal numbers at 72 hours, two weeks, eight weeks, and 24 weeks. Joint contracture was measured, and cartilage and synovial samples underwent histological analysis.


Bone & Joint Research
Vol. 5, Issue 2 | Pages 61 - 65
1 Feb 2016
Scott EEF Hamilton DF Wallace RJ Muir AY Simpson AHRW

Objectives

Temperature is known to influence muscle physiology, with the velocity of shortening, relaxation and propagation all increasing with temperature. Scant data are available, however, regarding thermal influences on energy required to induce muscle damage.

Methods

Gastrocnemius and soleus muscles were harvested from 36 male rat limbs and exposed to increasing impact energy in a mechanical test rig. Muscle temperature was varied in 5°C increments, from 17°C to 42°C (to encompass the in vivo range). The energy causing non-recoverable deformation was recorded for each temperature. A measure of tissue elasticity was determined via accelerometer data, smoothed by low-pass fifth order Butterworth filter (10 kHz). Data were analysed using one-way analysis of variance (ANOVA) and significance was accepted at p = 0.05.


Bone & Joint Research
Vol. 3, Issue 6 | Pages 212 - 216
1 Jun 2014
McConaghie FA Payne AP Kinninmonth AWG

Objectives

Acetabular retractors have been implicated in damage to the femoral and obturator nerves during total hip replacement. The aim of this study was to determine the anatomical relationship between retractor placement and these nerves.

Methods

A posterior approach to the hip was carried out in six fresh cadaveric half pelves. Large Hohmann acetabular retractors were placed anteriorly, over the acetabular lip, and inferiorly, and their relationship to the femoral and obturator nerves was examined.


Bone & Joint Research
Vol. 2, Issue 2 | Pages 41 - 50
1 Feb 2013
Cottrell JA Keshav V Mitchell A O’Connor JP

Objectives

Recent studies have shown that modulating inflammation-related lipid signalling after a bone fracture can accelerate healing in animal models. Specifically, decreasing 5-lipoxygenase (5-LO) activity during fracture healing increases cyclooxygenase-2 (COX-2) expression in the fracture callus, accelerates chondrogenesis and decreases healing time. In this study, we test the hypothesis that 5-LO inhibition will increase direct osteogenesis.

Methods

Bilateral, unicortical femoral defects were used in rats to measure the effects of local 5-LO inhibition on direct osteogenesis. The defect sites were filled with a polycaprolactone (PCL) scaffold containing 5-LO inhibitor (A-79175) at three dose levels, scaffold with drug carrier, or scaffold only. Drug release was assessed in vitro. Osteogenesis was assessed by micro-CT and histology at two endpoints of ten and 30 days.


The Journal of Bone & Joint Surgery British Volume
Vol. 94-B, Issue 10 | Pages 1433 - 1438
1 Oct 2012
Lam W Guo X Leung K Kwong KSC

This study was designed to test the hypothesis that the sensory innervation of bone might play an important role in sensing and responding to low-intensity pulsed ultrasound and explain its effect in promoting fracture healing. In 112 rats a standardised mid-shaft tibial fracture was created, supported with an intramedullary needle and divided into four groups of 28. These either had a sciatic neurectomy or a patellar tendon resection as control, and received the ultrasound or not as a sham treatment. Fracture union, callus mineralisation and remodelling were assessed using plain radiography, peripheral quantitative computed tomography and histomorphology.

Daily ultrasound treatment significantly increased the rate of union and the volumetric bone mineral density in the fracture callus in the neurally intact rats (p = 0.025), but this stimulating effect was absent in the rats with sciatic neurectomy. Histomorphology demonstrated faster maturation of the callus in the group treated with ultrasound when compared with the control group. The results supported the hypothesis that intact innervation plays an important role in allowing low-intensity pulsed ultrasound to promote fracture healing.


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 9 | Pages 1317 - 1324
1 Sep 2010
Solomon LB Lee YC Callary SA Beck M Howie DW

We dissected 20 cadaver hips in order to investigate the anatomy and excursion of the trochanteric muscles in relation to the posterior approach for total hip replacement. String models of each muscle were created and their excursion measured while the femur was moved between its anatomical position and the dislocated position. The position of the hip was determined by computer navigation. In contrast to previous studies which showed a separate insertion of piriformis and obturator internus, our findings indicated that piriformis inserted onto the superior and anterior margins of the greater trochanter through a conjoint tendon with obturator internus, and had connections to gluteus medius posteriorly. Division of these connections allowed lateral mobilisation of gluteus medius with minimal retraction. Analysis of the excursion of these muscles revealed that positioning the thigh for preparation of the femur through this approach elongated piriformis to a maximum of 182%, obturator internus to 185% and obturator externus to 220% of their resting lengths, which are above the thresholds for rupture of these muscles. Our findings suggested that gluteus medius may be protected from overstretching by release of its connection with the conjoint tendon. In addition, failure to detach piriformis or the obturators during a posterior approach for total hip replacement could potentially produce damage to these muscles because of over-stretching, obturator externus being the most vulnerable


The Journal of Bone & Joint Surgery British Volume
Vol. 92-B, Issue 1 | Pages 159 - 163
1 Jan 2010
Aykut S Öztürk A Özkan Y Yanik K İlman AA Özdemir RM

We studied the effects of coating titanium implants with teicoplanin and clindamycin in 30 New Zealand White rabbits which were randomly assigned to three groups. The intramedullary canal of the left tibia of each rabbit was inoculated with 500 colony forming units of Staphylococcus aureus. Teicoplanin-coated implants were implanted into rabbits in group 1, clindamycin-coated implants into rabbits in group 2, and uncoated implants into those in group 3. All the rabbits were killed one week later. The implants were removed and cultured together with pieces of tibial bone and wound swabs. The rate of colonisation of the organisms in the three groups was compared.

Organisms were cultured from no rabbits in group 1, one in group 2 but from all in group 3. There was no significant difference between groups 1 and 2 (p = 1.000). There were significant differences between groups 1 and 3 and groups 2 and 3 (p < 0.001). Significant protection against bacterial colonisation and infection was found with teicoplanin- and clindamycin-coated implants in this experimental model.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 4 | Pages 527 - 534
1 Apr 2008
Merican AM Amis AA

Anatomical descriptions of the lateral retinaculum have been published, but the attachments, name or even existence of its tissue bands and layers are ill-defined. We have examined 35 specimens of the knee. The deep fascia is the most superficial layer and the joint capsule is the deepest. The intermediate layer is the most substantial and consists of derivatives of the iliotibial band and the quadriceps aponeurosis. The longitudinal fibres of the iliotibial band merge with those of the quadriceps aponeurosis adjacent to the patella. These longitudinal fibres are reinforced by superficial arciform fibres and on the deep aspect by transverse fibres of the iliotibial band. The latter are dense and provide attachment of the iliotibial band to the patella and the tendon of vastus lateralis obliquus.

Our study identifies two important new findings which are a constant connection of the deep fascia to the quadriceps tendon superior and lateral to the patella, and, a connection of the deeper transverse fibres to the tendon of vastus lateralis obliquus.


The Journal of Bone & Joint Surgery British Volume
Vol. 90-B, Issue 2 | Pages 254 - 257
1 Feb 2008
Nakajima T Ohtori S Inoue G Koshi T Yamamoto S Nakamura J Takahashi K Harada Y

Using a rat model the characteristics of the sensory neurones of the dorsal-root ganglia (DRG) innervating the hip were investigated by retrograde neurotransport and immunohistochemistry. Fluoro-Gold solution (FG) was injected into the left hip of ten rats. Seven days later the DRG from both sides between T12 and L6 were harvested. The number of FG-labelled calcitonin gene-related peptide-immunoreactive or isolectin B4-binding neurones were counted. The FG-labelled neurones were distributed throughout the left DRGs between T13 and L5, primarily at L2, L3, and L4. Few FG-labelled isolectin B4-binding neurones were present in the DRGs of either side between T13 and L5, but calcitonin gene-related peptide-immunoreactive neurones made up 30% of all FG-labelled neurones. Our findings may explain the referral of pain from the hip to the thigh or lower leg corresponding to the L2, L3 and L4 levels. Since most neurones are calcitonin gene-related peptide-immunoreactive peptide-containing neurones, they may have a more significant role in the perception of pain in the hip as peptidergic DRG neurones


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 7 | Pages 971 - 976
1 Jul 2007
Kampa RJ Prasthofer A Lawrence-Watt DJ Pattison RM

In order to determine the potential for an internervous safe zone, 20 hips from human cadavers were dissected to map out the precise pattern of innervation of the hip capsule. The results were illustrated in the form of a clock face. The reference point for measurement was the inferior acetabular notch, representing six o’clock. Capsular branches from between five and seven nerves contributed to each hip joint, and were found to innervate the capsule in a relatively constant pattern. An internervous safe zone was identified anterosuperiorly in an arc of 45° between the positions of one o’clock and half past two.

Our study shows that there is an internervous zone that could be safely used in a capsule-retaining anterior, anterolateral or lateral approach to the hip, or during portal placement in hip arthroscopy.


The Journal of Bone & Joint Surgery British Volume
Vol. 89-B, Issue 1 | Pages 116 - 120
1 Jan 2007
Laing AJ Dillon JP Condon E Coffey JC Street JT Wang JH McGuinness AJ Redmond HP

Post-natal vasculogenesis, the process by which vascular committed bone marrow stem cells or endothelial precursor cells migrate, differentiate and incorporate into the nacent endothelium and thereby contribute to physiological and pathological neurovascularisation, has stimulated much interest. Its contribution to neovascularisation of tumours, wound healing and revascularisation associated with ischaemia of skeletal and cardiac muscles is well established. We evaluated the responses of endothelial precursor cells in bone marrow to musculoskeletal trauma in mice.

Bone marrow from six C57 Black 6 mice subjected to a standardised, closed fracture of the femur, was analysed for the combined expression of cell-surface markers stem cell antigen 1 (sca-1+) and stem cell factor receptor, CD117 (c-kit+) in order to identify the endothelial precursor cell population. Immunomagnetically-enriched sca-1+ mononuclear cell (MNCsca-1+) populations were then cultured and examined for functional vascular endothelial differentiation. Bone marrow MNCsca-1+,c-kit+ counts increased almost twofold within 48 hours of the event, compared with baseline levels, before decreasing by 72 hours.

Sca-1+ mononuclear cell populations in culture from samples of bone marrow at 48 hours bound together Ulex Europus-1, and incorporated fluorescent 1,1′-dioctadecyl- 3,3,3,’3′-tetramethylindocarbocyanine perchlorate-labelled acetylated low-density lipoprotein intracellularily, both characteristics of mature endothelium.

Our findings suggest that a systemic provascular response of bone marrow is initiated by musculoskeletal trauma. Its therapeutic manipulation may have implications for the potential enhancement of neovascularisation and the healing of fractures.


The Journal of Bone & Joint Surgery British Volume
Vol. 88-B, Issue 10 | Pages 1401 - 1405
1 Oct 2006
Honl M Schwieger K Salineros M Jacobs J Morlock M Wimmer M

We compared the orientation of the acetabular component obtained by a conventional manual technique with that using five different navigation systems.

Three surgeons carried out five implantations of an acetabular component with each navigation system, as well as manually, using an anatomical model. The orientation of the acetabular component, including inclination and anteversion, and its position was determined using a co-ordinate measuring machine.

The variation of the orientation of the acetabular component was higher in the conventional group compared with the navigated group. One experienced surgeon took significantly less time for the procedure. However, his placement of the component was no better than that of the less experienced surgeons. Significantly better inclination and anteversion (p < 0.001 for both) were obtained using navigation. These parameters were not significantly different between the surgeons when using the conventional technique (p = 0.966).

The use of computer navigation helps a surgeon to orientate the acetabular component with less variation regarding inclination and anteversion.


The Journal of Bone & Joint Surgery British Volume
Vol. 87-B, Issue 2 | Pages 261 - 266
1 Feb 2005
Földhazy Z Arndt A Milgrom C Finestone A Ekenman I

Strains applied to bone can stimulate its development and adaptation. High strains and rates of strain are thought to be osteogenic, but the specific dose response relationship is not known. In vivo human strain measurements have been performed in the tibia to try to identify optimal bone strengthening exercises for this bone, but no measurements have been performed in the distal radial metaphysis, the most frequent site of osteoporotic fractures. Using a strain gauged bone staple, in vivo dorsal metaphyseal radial strains and rates of strain were measured in ten female patients during activities of daily living, standard exercises and falls on extended hands. Push-ups and falling resulted in the largest compression strains (median 1345 to 3146 με, equivalent to a 0.1345% to 0.3146% length change) and falling exercises in the largest strain rates (18 582 to 45 954 με/s). On the basis of their high strain and/or strain rates these or variations of these exercises may be appropriate for distal radial metaphyseal bone strengthening.


The Journal of Bone & Joint Surgery British Volume
Vol. 83-B, Issue 2 | Pages 295 - 301
1 Mar 2001
Kim Y Kim J Cho S

Six pairs of human cadaver femora were divided equally into two groups one of which received a non-cemented reference implant and the other a very short non-dependent experimental implant. Thirteen strain-gauge rosettes were attached to the external surface of each specimen and, during application of combined axial and torsional loads to the femoral head, the strains in both groups were measured. After the insertion of a non-cemented femoral component, the normal pattern of a progressive proximal-to-distal increase in strains was similar to that in the intact femur and the strain was maximum near the tip of the prosthesis. On the medial and lateral aspects of the proximal femur, the strains were greatly reduced after implantation of both types of implant. The pattern and magnitude of the strains, however, were closer to those in the intact femur after insertion of the experimental stem than in the reference stem. On the anterior and posterior aspects of the femur, implantation of both types of stem led to increased principal strains E1, E2 and E3. This was most pronounced for the experimental stem. Our findings suggest that the experimental stem, which has a more anatomical proximal fit without having a distal stem and cortex contact, can provide immediate postoperative stability. Pure proximal loading by the experimental stem in the metaphysis, reduction of excessive bending stiffness of the stem by tapering and the absence of contact between the stem and the distal cortex may reduce stress shielding, bone resorption and thigh pain