There is no consensus regarding the optimum frequency of ultrasound for monitoring the response to Pavlik harness (PH) treatment in developmental dysplasia of hip (DDH). The purpose of our study was to determine if a limited-frequency hip ultrasound (USS) assessment in children undergoing PH treatment for DDH had an adverse effect on treatment outcomes when compared to traditional comprehensive ultrasound monitoring.

This study was a single-center non-inferiority randomized controlled trial. Children aged less than six months of age with dislocated, dislocatable and stable dysplastic hips undergoing a standardized treatment program with a PH were randomized, once stability had been achieved, to our current standard USS monitoring protocol (every clinic visit) or to a limited-frequency ultrasound protocol (USS only until hip stability and then end of treatment). Groups were compared based on alpha angle at the end of treatment, acetabular indices (AI) and IHDI grade on follow up radiographs at one-year post harness and complication rates. The premise was that if there were no differences in these outcomes, either protocol could be deemed safe and effective.

One hundred patients were recruited to the study; after exclusions, 42 patients completed the standard protocol (SP) and 36 completed the limited protocol (LP). There was no significant difference between the mean age between both groups at follow up x-ray (SP: 17.8 months; LP: 16.6 months; p=0.26). There was no difference between the groups in mean alpha angle at the end of treatment (SP: 69°; LP: 68.1°: p=0.25). There was no significant difference in the mean right AI at follow up (SP: 23.1°; LP: 22.0°; p=0.26), nor on the left (SP:23.3°; LP 22.8°; p=0.59). All hips in both groups were IHDI grade 1 at follow up. The only complication was one femoral nerve palsy in the SP group. In addition, the LP group underwent a 60% reduction in USS use once stable.

We found that once dysplastic or dislocated hips were reduced and stable on USS, a limited- frequency ultrasound protocol was not associated with an inferior complication or radiographic outcome profile compared to a standardized PH treatment pathway. Our study supports reducing the frequency of ultrasound assessment during PH treatment of hip dysplasia. Minimizing the need for expensive, time-consuming and in-person health care interventions is critical to reducing health care costs, improving patient experience and assists the move to remote care. Removing the need for USS assessment at every PH check will expand care to centers where USS is not routinely available and will facilitate the establishment of virtual care clinics where clinical examination may be performed remotely.

The purpose of this study is the evaluate the net promotor score of arthroscopic subacromial decompression and rotator cuff repair.

The Friends and Family Test, a variant of the Net Promoter Score, was adapted for the National Health Service to evaluate overall patient satisfaction and how likely patients are to recommend an intervention. It ranges from −100 to 100. Positive scores indicate good performance.

This study quantifies the scores in 71 patients at 1 year following arthroscopic sub acromial decompression and rotator cuff repair. All of the procedures were performed by 1 consultant shoulder specialist. The patient filled out a shoulder questionnaire pre-operatively, at 6 months and 1 year.

The score was 72 for subacromial decompression (n = 32) and 85 for rotator cuff repair +/− decompression (n = 39). Oxford shoulder score was also taken and had a rise of 4.3 and 6.9 respectively. Our study indicates that these procedures are highly valued and are recommended by patients according to the Friends and Family Test. The results of the Friends and Family Test correlated well with postoperative functional improvement and satisfaction.

We conclude from this study that a compound score based on the Friends and Family Test is a useful addition to traditional measures of patient satisfaction.

The Laboratory Risk Indicator for Necrotising Fasciitis (LRINEC) score was developed in 2004 to risk-stratify patients with soft tissue infections using common blood tests when the clinical picture is equivocal. A score ≥ 6 conferred a positive predictive value (PPV) of 92% and negative predictive value of 96% for necrotising fasciitis.

We retrospectively calculated LRINEC scores for Orthopaedic patients admitted to ITU in our hospital with limb soft-tissue infection and confirmed Group-A Streptococcus or Staphylococcus in fluid, blood, tissue or swab culture between 2010–2017 (n=10). Mean age = 57.4 and 60% were female. Half of all patients died during admission. Mean LRINEC score of all patients was 5.3±3.1 (median = 6). Mean score in deceased patients was 4.8±2.8 (scores: 0,5,6,6,7; median = 6); in discharged patients mean = 5.8±3.7 (scores: 0,5,7,7,10; median = 7). 6 patients had a score ≥6, making our PPV 60%. 4 patients had necrotising fasciitis confirmed on histology (LRINEC scores = 0,5,7,10).

Our PPV of 60% is less than the figure obtained in the original paper. 2 patients with a LRINEC score <6 died during admission, including a patient with a score of 0. Furthermore, a patient with necrotising fasciitis confirmed on histology also had a LRINEC score of 0. We conclude that LRINEC scores should not delay surgery when clinical suspicion is high, and should be used as an adjunct to clinical decision-making, rather than a replacement, as patients with low LRINEC scores can also have confirmed necrotising fasciitis and poor outcomes.

Introduction

Training the next generation of surgeon's forms part of routine Consultant practice. Stress causes activation of the Autonomic Nervous System and this can be directly measured using heart rate (HR). Training time is limited with pressures from EWTD and management and efficiency targets. The aim of this study was to assess whether being an orthopaedic trainer is more stressful than performing the surgery.

Introduction

The hierarchical structure of tendon results in a complex mechanical strain environment, with tenocytes experiencing both tension and shear during loading. The mechanotransduction mechanisms involved in sensing these environments is currently unclear. To better understand the effects of shear and tension on cell behaviour, a fibre composite system able to recapitulate the physiological shear-tension ratio found in tendons, was used. Cell attachment within the composite was achieved by using either a collagen type I mimetic peptide, DGEA, or a fibronectin associated peptide, YRGDS, and the gene expression response analysed after loading.

Percutaneous Achilles tenotomy is an integral part of the Ponseti technique. Though considered as a simple procedure, many authors have reported serious neurovascular complications that include iatrogenic injury to the lesser saphenous vein, the posterior tibial neurovascular bundle, the sural artery and pseudoaneurysm formation. The authors describe the results of their new tenotomy technique, the ‘Posterior to Anterior Controlled’ (PAC) technique in an attempt to eliminate such complications.

This is a prospective study. Infants < 1 year of age with idiopathic clubfoot were taken up for the Ponseti technique of correction. Tenotomy was performed by the ‘PAC’ technique under local anaesthesia if passive dorsiflexion was found to be < 15 degrees. Outcome measures included completeness of the tenotomy (by ultrasonography), improvement in the equinus angle and occurrence of neurovascular complications.

40 clubfeet in 22 patients underwent ‘PAC’ tenotomy. The mean age was 3.5 months. The tenotomy was found to be complete in all cases. The equinus angle improved by an average of 78.5 degrees (range 70–95 degrees), which was statistically significant (p < 0.05, students t test). Mild soakage of the cast with blood was noted in 21 (52.5%) cases. No neurovascular complication was noted. The average follow-up was 12.2 months (range 9–18 months).

The ‘PAC’ tenotomy virtually eliminates the possibility of neurovascular damage, maintains the percutaneous nature of the procedure, is easy to learn and can be performed even by relatively inexperienced surgeons safely and effectively as an office procedure under local anaesthesia.

The quality of femoral stem cementation has been shown to be a useful indicator of long-term survival of the total hip arthroplasty. Barrack's cementation grading is widely used but has certain limitations. It is based upon second-generation cementation technique and has high inter- and intra-observer variability. We introduce a new femoral cementation index based upon lengths of radiological lucency and cement-bone interface on AP and lateral views.

Five observers graded femoral cementation of radiographs of 30 primary hip arthroplasties using Barrack's grading and the new index on two occasions and Inter- & Intra-observer reliability was assessed. We also assessed the correlation between proximal femoral anatomy (calcar-canal ratio) & structural bone quality (using cortical index) with cementation using the new index in 50 patients.

Inter- and intra-observer reliability of the new index showed intraclass correlation coefficient 0.79 and 0.82 respectively and Barrack's grading system showed Kappa value- 0.20 (inter-observer) and 0.55 (intra-observer) reliability.

There was poor correlation between the calcar-canal ratio and the quality of cementation [Pearson's coefficient −0.04 (p< 0.05)]. There was some correlation between the cortical index and the quality of cementation [Pearson's coefficient 0.46 (p < 0.05)].

Our new index is a reliable method of assessing femoral cementation. The anatomy of femoral canal didn't have any significant influence on the quality of cementation achieved as assessed by our new index. The femoral cortical structural quality seemed to have some positive influence on the quality of cementation.

Financial impact and patient satisfaction with four different anticoagulants for hip and knee arthroplasty in patients with a previous history of VTE- A prospective randomised trial

Introduction

Adolescent idiopathic scoliosis (AIS) is the most common paediatric spinal deformity, affecting about 3% of school-aged children worldwide. This disorder occurs in otherwise healthy children who bear no obvious deficiencies in the components of the spinal column itself. The cause of AIS is poorly understood, as is implied by the name. Lesions of the bony composition of the vertebrae, the vertebral endplates, the paraspinous muscles, or the neurological system each have been proposed to explain disease pathogenesis. Progress has been hampered by the absence of an obvious AIS animal model. Consequently we have used genetic studies in human populations to identify factors underlying AIS susceptibility.

The complex inheritance and population frequency of AIS suggest that many genetic factors are involved in this disease. To search comprehensively for such factors we previously undertook the first genome-wide association study (GWAS) of AIS susceptibility in a cohort of 419 families in Texas, USA. We found that chromosome 3 SNPs in the proximity of the CHL1 gene yielded strongest results, which we replicated in additional cohorts (rs10510181 OR 1·49, 95% CI 1·29–173, p=2·58×10–8). CHL1 is of interest because it encodes an axon guidance protein and is functionally related to the ROBO3 gene that causes hereditary gaze palsy with progressive scoliosis (HGPPS), a rare disease marked by severe scoliosis. Here we expanded the study to 702 Texas families.

Objective

Arthroscopic rotator cuff repairs now yield a similar footprint as open procedures with several advantages, including reduced tissue trauma, post-operative pain, swelling, and concern about the deltoid attachment. We present a new simple and reproducible technique for arthroscopic rotator cuff repair.

Introduction

Osteoarthritis (OA) has historically been thought of as a degenerative joint disease, but inflammation and angiogenesis are increasingly being recognised as contributing to the pathogenesis, symptoms and progression of OA. b-dystroglycan (b-DG) is a pivotal element of the transmembrane adhesion molecule involved in cell-extracellular matrix adhesion and angiogenesis. Matrix metalloproteinases (MMPs) are the main enzymes responsible for cartilage extracellular matrix breakdown and are also implicated in both angiogenesis and b-DG degradation in a number of malignancies. We aimed to investigate the expression and localisation of b-DG and MMP-3, -9, and -13 within cartilage, synovium and synovial fluid and establish their roles in the pathogenesis of OA.

Background: Surgery in adolescent idiopathic scoliosis is done mainly for cosmesis and outcomes are reported in terms of radiological measurements (Cobb angle), outcome questionnaires (SRS-22) and back surface measurements (Scoliometer & Quantec). Previous studies have shown correlations between SRS-22 and objective radiological and back surface measures at a point in time (Asher et al 2003 & 2004).

Aim: of the study was to evaluate the association between subjective and objective outcomes in posterior instrumented scoliosis correction.

Patients and Methods: 43 patients with late-onset thoracic idiopathic scoliosis were included in the study with 39 girls and 4 boys with a mean age 13.2 years. Mean pre-operative Cobb angle was 71o. The objective assessment of back surface was done using a scoliometer and the POTSI & Suzuki Hump Sum scores. The subjective assessment was done using the Scoliosis Research Society (SRS)-22 score. The assessments were done pre-operatively and then post-operatively at 8-weeks and one year.

Results: The average percentage improvement in various outcomes after surgery was as follows: Cobb angle (71%), Maximum Angle of Trunk Inclination (Max. ATI) (52 % at 8 weeks and 39 % at 1 year), POTSI (57%), Hump Sum (24%), SRS-Total (14%), SRS-self image (14%). Pre-operatively, there were good inter-correlations (r= 0.4–0.7) between the objective measures (Max. ATI, POTSI and Hump Sum). Significant correlation was found between SRS-22 total versus Cobb angle (p-0.001, r=0.41). No significant correlation was found between the SRS-22 (total & domains) versus the Max. ATI, POTSI or the Hump Sum scores. Post-operatively, good correlation (r=0.6) was again found between the objective measures (Max. ATI, POTSI and Hump Sum) of back surface measurements (absolute and percentage). No significant correlation was found between SRS-22 (domains & total) versus Cobb angle correction, Max. ATI, POTSI, or Hump Sum.

Conclusion: In this study SRS-22 was found to be responsive to change with surgery, especially the self-image/appearance domain. However the SRS-22 score after surgery and the change in this score did not correlate with the change in objective measures of back surface deformity after surgery.

Introduction: Metastatic spinal disease continues to be a challenge in the management of patients with advanced malignancy. Anterior en bloc spondylectomy and stabilisation, a more extensive procedure, is favoured as it is thought to provide a curative resection and improve the overall outcome (Tomita et al,2002; Wiegel, 1999).

Aim: The aim of this study was to see if there is still a role for extensive posterior decompression (Wide laminectomy and transpedicular decompression) with stabilisation in the treatment of these patients which is the mode of treatment used in our institution and favoured by some others (Bauer, 1997)

Patients and Methods: We retrospectively reviewed a cohort of patients treated in our institute by extensive posterior decompression and stabilisation between 2000 to 2006. We excluded patients having haematological primaries and anterior surgery and those with inadequate data.

Outcome measures used were post operative mortality, Post operative improvement in Frankel score, level of pain perception, level of mobility and ability to perform activities of daily living.

Results: 52 patients had posterior surgery with Colarado instrumentation being used in a majority. There was a slight male preponderance with an average age of 67 years. The mean length of follow up was 12 months.57% patients were dead at last review. 52 % patients showed an improvement in Frankel scores. There was a significant decrease in analgesic requirement post operatively with an improvement in pain scores. Similarly there was an improvement in the ability to perform activities of daily living and the level of mobility. No major surgical complications were noted bar a few superficial wound infections. Revision surgery was done in 6 cases. In 2 it was for a tumour recurrence, for broken rods in 2 and converted to anterior in 2. There were 4 immediate peri operative deaths.

Conclusion: Our results are comparable to Bauer et al, 1997 and other series. Posterior spinal surgery is very much a viable treatment option to treat selected cases with metastatic spinal disease. It avoids all the complications and morbidity of anterior surgery while producing an overall improvement in pain, the quality of life, level of mobility and neurological status.

Background: Total knee replacement remains one of the most common knee surgery practices worldwide. The operative procedure universally requires the use of cutting jigs to resect predetermined amounts of bone irrespective of the preoperative anatomy and morphology of the femur and tibia.

Aims: The aims of this study were to elucidate anatomical morphological differences between ethnicities pre-operatively and to assess whether any change elucidated was preserved post-operatively.

Method: This was a retrospective study comparing the pre and postoperative lateral view X-Rays of TKRs performed. Distances measured from most prominent anterior point to midline and the most prominent posterior point to midline and their ratio was compared between two ethnic groups. Each x-ray measurement was triple checked.

Results: The study groups comprised of 60 Caucasian knees and 40 Asian knees. Preoperatively the mean ratio was 0.55 in Caucasians and 0.44 in Asians, with this difference being statistically significant (p value < 0.005). Post operatively the mean ratio was 0.59 in Caucasians and 0.55 in Asians and this difference was not statistically significant (p value =0.166). These findings were also cross-checked with range of movement measurements post-operatively in the same group of patients. There was no comparable improvement in range of movements (ROM) post-operatively in the Asian group.

Conclusion: We infer that the present TKR cutting jigs are not taking into account the anatomical differences within the knee of Asians individuals. This is converting the post operative distal femurs of this group to become morphologically comparable to the Caucasian knee and this is possibly affecting the kinematics of those knees leading to no significant improvement in the post operative ROM and affecting satisfaction with surgery.

The purpose of this study is to evaluate the effectiveness of current surgical management of pelvic acetabular fractures providing insight into the outcomes of fractures treated operatively using validated scoring systems.

20 Patients were surgically treated over a 2 year period at the Hudders field Royal Infirmary Hospital, United Kingdom. All were operated on by a single surgeon following pelvic and acetabular fractures. The first part of the study consisted of a review of the clinical records and x-rays done by 2 different observers. All the pelvic fractures were classified according to the Young-Burgess classification, and acetabular injuries according to the Letournels classification. The notes were assessed for probability of survival on admission and ‘ISS scoring’. The clinical records were reviewed for post operative complications, a protocol for follow up management, involvement of HDU, and any relevant re-admissions. The second portion of the retrospective study consisted of patient reviews at the clinic, the minimum being 6 months post operatively. Recent x-rays were reviewed for bone healing, heterotrophic ossification and avascular necrosis. The patients wound healing was assessed. Clinical results were recorded using the Oxford Hip score and the SF-36.

The results were analysed whilst ISS scoring varied from 8–32 with most of the patients. All patients had a good reduction and fracture healing. Complications noted were wound infection in 5%, and heterotrophic ossification in 5%. There were no nerve palsys, no DVT or pulmonary embolus, and no patients had avascular necrosis of the femoral head. Most patients had returned to near normal activities, with low pain scores. The Oxford Hip score ranged between 12–25, and the SF-36 score between 80 & 100.

The authors concluded that patients with complex acetabular fractures can be managed effectively in a district hospital set up. Osteoarthrosis of the hip can be avoided if an anatomical reduction is achieved.

Introduction: Peri-prosthetic osteolysis due to wear has been acknowledged as a major challenge to long-term survival of hip arthroplasty and this has led to a search for alternative articular bearing couples. We present our experience with metal-on-metal (Metasul^®) articulation with a minimum patient follow-up of 5 years.

Materials and methods: 193 patients (215 hips) were reviewed; 187 (209 hips) had a follow-up of ≥ 5 years. Hip scores were completed and radiographs performed at follow-up visits and data was entered prospectively into software (orthocom) designed by Sulzer Ltd.. Serial radiographs were reviewed retrospectively along with hospital notes and the database.

Results: mean age was 70 (± 7.46) years (range 47–86 years). Female: male was 143:44. Most common pre-operative diagnoses were: osteoarthritis (147) and intra-capsular hip fracture (22).

Mean pre-operative HHS was 39.7 (±15.7) and the corresponding pain score was 13.4 (±8.49). The average post-operative scores were 89.5, 87.3, 88.4 and 85.8 at 1 year, 3 years, 5 years and final follow-up respectively. The corresponding pain scores were 42.7, 41.98, 42.1 and 41.94. Implant survival for the cohort as a whole was 95.5% at 12 years (ci: 88%–100%). Survivorship for the Weber Metasul cup was 93.4% at 12 years (ci: 82.7%–100%) and for armor cup was 100% at 11 years.

Complications included: dislocations (7), periprosthetic fractures (8), deep infection- early (3) & late (3), aseptic loosening (cup) (2) & heterotopic ossification (9). There were no untoward systemic complications with regards to metal ion release.

Discussion: We believe that second generation metal-on-metal implants (Metasul^®) with improved design and better lubrication show better survival with regards to aseptic loosening and reduction in osteolysis in the medium-term. Concerns regarding metal ion and metal particle release remain theoretical but are kept under constant review.

Introduction More than 2% of the general population is reported to be affected by adhesive capsulitis. The incidence is greater in patients with diabetes than in the general population for both IDDM and NIDDM. This study sought to test the hypotheses that diabetes does not have an effect on outcome and does not contribute to morbidity.

Materials and methods Data were collected retrospectively by reviewing medical records from 1996 to 2005. A total of 148 case notes were evaluated to identify patients with a diagnosis of frozen shoulder who underwent MUA ± arthroscopy ± release. Twenty-two patients (22 shoulders), 12 of whom had diabetes, agreed to participate and were included. The diabetic and non-diabetic groups were broadly comparable with respect to demographic characteristics. Invited patients were asked to assess current physical function and symptoms by completing a shortened version of the DASH outcome measure questionnaire prior to attending the clinic and a further questionnaire detailing pre-op symptoms. Physical function was assessed and calculated using the Constant score system.

Results The median pre-operative DASH score was 72.73 in the diabetic group and 71.00 in the non-diabetic group (difference 2.3%). The median post-operative DASH score was 27.27 in the diabetic group and 28.86 in the non-diabetic group (difference 5.51%). The median postoperative Constant score was 60.00 in the diabetic group and 59.50 in the non-diabetic group (difference 0.83%).

Conclusion The pre- and post-operative DASH results and post-operative Constant score showed little difference between diabetic and non-diabetic patients. While giving due cognisance to the small number of patients included and the retrospective design of the study, the results support the hypothesis that diabetes does not have an effect on outcome following MUA or arthroscopy for adhesive capsulitis and does not contribute to morbidity.

Introduction: Osteoarthritis (OA) has historically been thought of as a degenerative joint disease, but inflammation and angiogenesis are increasingly being recognised as contributing to the pathogenesis, symptoms and progression of OA. β-dystroglycan (β-DG) is a pivotal element of the transmembrane adhesion molecule involved in cell-extracellular matrix adhesion and angiogenesis. Matrix metalloproteinases (MMPs) are the main enzymes responsible for cartilage extracellular matrix breakdown and are also implicated in both angiogenesis and β-DG degradation in a number of malignancies. We aimed to investigate the expression and localisation of β-DG and MMP-3, -9, and -13 within cartilage, synovium and synovial fluid and establish their roles in the pathogenesis of OA.

Methods: Following ethical committee approval, cartilage, synovium and synovial fluid were obtained from the hip joints of 5 osteoarthritic (patients undergoing total hip replacement) and 5 control hip joints (patients undergoing hemiarthroplasty for femoral neck fracture). The samples were analysed for β-DG expression using Western Blotting and for the distribution of β-DG, MMP-3, -9, and -13 using immunohistochemistry on paraffin embedded tissue.

Results: Whilst no significant expression of β-DG was found in cartilage or synovial fluid, β-DG was expressed in the smooth muscle of both normal and osteoarthritic synovial blood vessels. Moreover, β-DG was expressed in endothelium of blood vessels of OA synovium, but not in the normal endothelium. In the endothelium of osteoarthritic synovial blood vessels, β-DG co-localised with MMP −3 and −9.

Discussion: Our results demonstrate that β-DG does not act as a cell adhesion molecule binding chondrocytes to the ECM. However, specific immunolocalisation of β-DG within endothelium of inflamed OA blood vessels suggests that β-DG may play a role in angiogenesis associated with OA. Its co-localisation with MMP-3 and −9, previously reported to also have pro-angiogenic roles, may be linked. Further research is required to understand these roles more fully.

Introduction: There has been a renewed interest in metal-on-metal articulation in hip joint Arthroplasty. The reason for having metal-on-metal articulation is to reduce the volume of wear particles that are produced with THR. The outcome of reduced particle formation will hopefully be reduced osteolysis.

Methods: We reviewed the results of 139 primary hip arthroplasties (130 patients) performed using Metasul articulation and cemented Weber cup. Six patients were lost to follow-up leaving 133 hips (124 patients) for review with at least 5-year follow-up. The acetabular socket was the cemented Weber cup and Bone grafting of the acetabulum and application of a reinforcement ring was done where necessary. Cemented CF-30 femoral stem was used in all patients but one (PFMR). The study was conducted retrospectively based on the information collected from hospital notes and Orthocom database. Immediate post-operative films were seen to measure the cup and stem inclination and quality of cementing using the Barracks grading system.

Results: There were 102 females and 22 males in the cohort. Mean age was 73 years (SD-7.46, range 58–86). Left to right hip ratio was 52:81. Most common Pre-operative diagnosis was Osteoarthritis (103) followed by Intracapsular fracture neck of femur (20). The average follow-up was 7.23 years (range 5–10.9). Mean pre-operative Harris hip score was 42.09 and mean post-operative hip scores were 90.01, 86.84, 87.42 and 84.63 at 1-year, 3-year, 5-year and final follow-up with the corresponding pain scores were 42.9, 41.84, 41.56 and 41.56 respectively. Only two hips were revised for aseptic loosening of the cup with a 93.4% implant survivorship at 12 years. There was no case of aseptic stem loosening. No untoward systemic effects were noted in the cohort.

Discussion: We believe that in our study Metasul metal-on-metal articulation has shown satisfactory results with regards to aseptic loosening and reduction in osteolysis in medium-term.

Introduction: Osteoarthritis has historically been thought of as a degenerative joint disease, but inflam-mation and angiogenesis are increasingly being recognised as contributing to the pathogenesis, symptoms and progression of osteoarthritis. Beta-dystroglycan is a pivotal element of the transmembrane adhesion molecule involved in cell-extracellular matrix adhesion and angiogenesis. Matrix metalloproteinases are the main enzymes responsible for cartilage extracellular matrix breakdown and are also implicated in both angiogen-esis and beta-dystroglycan degradation in a number of malignancies. We aimed to investigate the expression and localisation of beta-dystroglycan and matrix metal-loproteinase 3, 9, and 13 within cartilage, synovium and synovial fluid and establish their roles in the pathogenesis of osteoarthritis.

Methods: Following ethical committee approval, cartilage, synovium and synovial fluid were obtained from the hip joints of 5 osteoarthritic (patients undergoing total hip replacement) and 5 control hip joints (patients undergoing hemiarthroplasty for femoral neck fracture). The samples were analysed for beta-dystroglycan expression using Western Blotting and for the distribution of beta-dystroglycan, matrix metalloproteinase 3, 9, and 13 using immunohistochemistry on paraffin embedded tissue.

Results: Whilst no significant expression of beta-dystro-glycan was found in cartilage or synovial fluid, beta-dys-troglycan was expressed in the smooth muscle of both normal and osteoarthritic synovial blood vessels. Moreover, beta-dystroglycan was expressed in endothelium of blood vessels of osteoarthritic synovium, but not in the normal endothelium. In the endothelium of osteo-arthritic synovial blood vessels, beta-dystroglycan co-localised with matrix metalloproteinase 3 and 9. Discussion: Our results demonstrate that beta-dystro-glycan does not act as a cell adhesion molecule binding chondrocytes to the extracellular matrix. However, specific immunolocalisation of beta-dystroglycan within endothelium of inflamed osteoarthritic blood vessels suggests that beta-dystroglycan may play a role in angiogenesis associated with osteoarthritis. Its co-localisation with matrix metalloproteinase 3 and 9, previously reported to also have pro-angiogenic roles, may be linked. Further research is required to understand these roles more fully.