Total hip and knee arthroplasty surgery has revolutionised the management of patients with arthritis. The musculoskeletal and cardiopulmonary complications of such surgery are well recognised, however hepatic complications are rare. Elevated liver function tests in the early post operative period were noted in a cohort of patients undergoing elective hip and knee arthroplasty. The aetiology and significance of this phenomenon is uncertain.

A prospective study of all patients undergoing elective total hip and knee arthroplasty in one hospital by the senior author over a four year period was undertaken. All patients (over 300) had liver function tests (LFT’s), renal profile and haematological indices recorded pre operatively, one day, one week and six weeks post operatively. A standardised anaesthetic and post operative regime was followed.

Significant elevation of the liver enzymes, ALT (from 59 to 120), AST (from 47 to 81) and GGT (from 39 to 50) was noted after one week. These values returned to normal after six weeks. The bilirubin levels were also raised at one day (from four to eight) and at one week (from four to ten). Alkaline phosphatase and globulin levels remained within normal parameters. There was a fall in albumin and total protein levels in the immediate post operative period.

In conclusion, many patients undergoing elective total hip and knee arthroplasty experience significant hepatic enzyme dysfunction in the early post operative period. This elevation of liver function tests returns to normal after six weeks. The significance of these findings including likely causes is discussed.

Total hip arthroplasty has improved the quality of life for many patients with osteoarthritis. Infection is a serious complication, difficult to treat and often requires removal of the prosthesis to eradicate the infection.

An analysis of the surgical management, risk factors, complications and outcome of infected total hip replacements. Thirty one consecutive patients underwent revision hip arthroplasty for infection between 1997 and 2003. Risk factors, co-morbidity, clinical presentation, biochemical profiles, microbiology, management and radiology were recorded. Outcome and complications following surgery are reviewed. Classification of infection after total hip arthroplasty was based on their clinical presentation—early postoperative, late chronic, or acute hematogenous infection, and positive intraoperative cultures.

All patients underwent resection arthroplasty, 26 had a two-stage revision, 1 had a three stage, 4 did not have a re-implantation. Staph Aureus was the most common organism identified. 16 patients were classified as late chronic insidious, 8 early post operative infection, 6 acute haematogenous and 1 occult intraoperative. Average total blood loss was 5 litres, average replacement was 7 units. 1 patient had a persistent infection. 3 underwent further surgery for dislocation, stem perforation or fracture. 5 patients had a persistent limp.

In infected revisions the bone stock is usually adequate, the soft tissues are very poor. Bivalving the femur allows for optimal cement removal. Blood loss can be significant with average replacement of 7 units. Meticulous removal of infected components, cement and tissue is essential for good long-term results.

The mechanism by which cells die is important in an immune response and its resolution. The role of apoptosis in sepsis and trauma, and its regulation by cytokines is unclear. During the systemic inflammatory response, rates of human neutrophil apoptosis are decreased. Peritoneal macrophage apoptosis has been induced by nitric oxide and Lipopolysaccharide (LPS) in vitro but this has not as yet been demonstrated in vivo.

We examined the induction and effects of macrophage apoptosis in a model of trauma and sepsis.

One hundred female CD-I mice were randomised into four groups: Control, Septic model, challenged with intraperitoneal LPS (1.Img/200ul/mouse), Traumatic model, received hind limb amputation (HLA) and a Combined trauma/septic model. After 24 hrs mice were sacrificed and peritoneal macrophages were assessed for apoptosis by morphology and DNA fragmentation by flow cytometry and DNA gel electrophoresis

Peritoneal lavage from septic models had a decreased percentage of macrophages in comparison to control and trauma groups. The septic model also had a significantly increased incidence of apoptosis in comparison to control and trauma levels. There was no significant difference between control and traumatic groups.

These findings demonstrate that in a murine model of sepsis, lipopolysaccharide induces macrophages apoptosis. Modulation of this immune response may have important roles in the management of trauma patients.

Waste disposal is an issue that affects us all. The amount and toxicity of medical waste has increased in line with increasing medical facilities and diagnostic and therapeutic procedures. Demand for landfill sites and increasing household and hospital waste loads, have made the current situation untenable. New thinking and new strategies must be employed

To investigate waste production in the operating department during a primary total hip arthroplasty.

A prospective observational study, waste from packaging and non-clinical materials in fifty consecutive total hip replacements. Weight, volume, cost of disposal and percentage of recycled items were recorded. Inappropriate segregation of waste was recorded and the hazards involved are discussed.

Domestic waste is compressed and buried at a cost of €222($383)/tonne. This extrapolates into a cost of about €1,500($2,589) yearly in the region and over €10,000($17,000) in Ireland. Cost to the environment, 2.6 tonnes locally, and 18.9 tonnes of surgical waste/year. Biological waste buried at €880 ($1,518)/tonne.

Reduce, Reuse and Recycle are the cornerstones of waste management. Medical staff need to understand how best to segregate waste and take advantage of opportunities for reuse and recycling. We must revisit the packaging of implants, the use of recycled paper.

Aseptic loosening is the single most important long-term complication of total joint arthroplasty. Wear debris induced inflammation stimulates osteoclastic resorption of bone. Cellular mechanisms involved in osteoblast viability in PWD induced inflammation is poorly understood.

Wear induced inflammation increases osteoblast necrosis and susceptibility to death by apoptosis. PMMA cement has a detrimental effect on osteoblast resistance to apoptosis, and that this is via an receptor mediated pathway. Osteoblast cell cultures (Human and MG63) were grown with and without PMMA cement and assessed for apoptosis and necrosis. TNF-α or Fas antibody simulated inflammation. Viability and apoptosis with PI exclusion, flow cytometry and western blotting assessed response.

Cement induced osteoblast necrosis up to 1 hour. This effect was negated after 24 hours. Culture of osteob1asts on cement had no direct effect on spontaneous apoptosis but susceptibility to inflammation was increased.

Polymerised cement has no direct effect on osteoblast cell death. Effects are mediated by inhibiting expression of anti-apoptotic protein (Bcl-2), and increasing susceptibility to inflammatory. Osteoblast resistance to death may represent a novel and important factor in aseptic loosening. The role of gene therapy is explored.

Aims: To correlate clinical imaging and surgical finding in patients with knee arthritis. In an attempt to identify specific lesions that correlate with the location of clinical pain.

Methods: 26 patients and 32 knees were eligible for inclusion in the study. All patients had been admitted for total knee arthroplasty. In all patients an attempt was made to correlate symptoms with radiographic findings and then intraoperative findings. A senior orthopaedic registrar carried out standard knee scores and clinical examinations, radiographs and a radiologist blindly evaluated MRI scans. The integrity of the articular cartilage as well as the menisci and ligaments were all graded.

Results: At clinical examination all patients score 70 or higher on a visual analogue scale. In eighteen patients, the maximum site of clinical tenderness was referable to the medial joint line. In seven patients symptoms were on the lateral aspect. Pain was recorded on a line diagram of the knee for analysis. MR images confirmed advanced arthritis with meniscal derangement with extrusion and maceration. Note was made of osteophyte formation, medial collateral ligament laxity and oedema and discrete osteochondral defects. Bone marrow bruising and oedema was also recorded. In nine patients subchondral cysts were identified with extensive associated bone oedema. At surgery, meniscal degeneration was identified in fifteen of twenty-six, meniscal tears were identified in six; the menisci were normal in two patients.

Discussion: These results suggest that there is a direct correlation between clinical symptoms and meniscal derangement in severe osteoarthritis. Isolated articular defects and bone marrow oedema did not correlate well with location of pain. Presence of medial collateral oedema correlated well with severity of radiological arthritis and clinical findings.

In summary, this study suggests that patients with symptomatic knee arthritis are likely to have meniscal derangement and medial collateral oedema. A greater understanding of the origin of pain in the degenerate knee may assist in the choice of management options for these patients.

Standard protocol following total hip arthroplasty dictates that the hip is kept in a position of abduction until soft tissue healing is sufficient to provide stability. This is maintained by use of an abduction pillow while in bed, meaning that the patient must sleep on their back. Many patients find this position uncomfortable and have significant difficulty in sleeping.

Aims: To assess the impact of sleep deprivation on recovery of the patient and quality of life in the peri-operative period.

Methods: Patient cohort consisted of elective admissions for total hip replacement. All were assessed using the Epworth sleep scale, SF-36 as well as the Hospital Anxiety and depression score. Body mass index and history of insomnia or obstructive sleep apnoea were recorded. Baseline oxygen saturation was compared with postoperative overnight saturation and request for night sedation.

Results: 64 consecutive patients undergoing total hip arthroplasty surgery were eligible for inclusion in the study. Mean age 68 (43 to 85), 42 females, 22 males, 62 patients were satisfied with the result of surgery, 1 patient with hip dysplasia had a persistent leg length inequality and one complained of back pain. All patients were nursed according to standard protocol with abduction pillow while in hospital and instructions to sleep on their back while at home. 18 patients did not fully comply with this instruction while at home. There were no early dislocations with a mean follow up of 5.4 months. Mean hospital anxiety and depression scores were significantly increased following surgery mean pre-operatively (5.2), to highest level (3.4) at two weeks, (8.5) at six weeks, returning to normal levels after three months (4.2). Epworth sleep scores were similarly increased with sleep patterns returning to normal at the three month stage. Increasingly, body mass index correlated significantly with poor scores and low oxygen saturation readings. This group of patients had a predisposition to obstructive sleep apnoea, which was predicated by sleeping on their backs, they require more night sedation and analgesia.

Conclusions: Standard precautions following total hip arthroplasty are not without morbidity. Sleep deprivation leading to increased anxiety and decreased satisfaction. Increased demand for night sedation and analgesia with their resultant costs and dependence. Sleeping in the supine position may also precipitate obstructive sleep apnoea in at risk patients.

Biopsy is a key step in the diagnosis of bone and soft tissue tumours. An inadequately performed biopsy may fail to allow proper diagnosis. An improperly planned biopsy may jeopardise plans for limb salvage surgery.

Aims: To analyse the effectiveness of core-needle biopsy for evaluation of suspected primary musculoskeletal neoplasms.

Methods: Core-needle biopsy was performed at our institution in 130 consecutive patients suspected of having a mesenchymal neoplasm. Details of the biopsy and any additional procedures were recorded including size of sample, method of localisation and any complications. Clinical and histological features of the neoplasm and previous radiological or histological diagnosis were compared. Core-needle biopsy results were correlated with results from specimens subsequently obtained at definitive surgery.

Results: 130 consecutive core biopsies were performed for evaluation of suspected primary musculoskeletal neoplasms. All patients tolerated the procedure well and there were no significant complications. A definitive diagnosis was obtained from a single core biopsy in 107 (82%) patients; an additional biopsy was necessary in 24 (18%) following equivocal histology. Twenty-three (96%) of these repeat biopsies were an open procedure. In 98% of patients, core-needle biopsy results were concordant with results from specimens subsequently obtained at surgery with respect to tumour histological features and grade. The accuracy and rate of performance of open biopsy for soft tissue lesions were not significantly different from those for bone lesions.

Conclusions: Obtaining tissue safely, for diagnosis of bone and soft tissue tumours is the goal of all biopsies The biopsy, however, must be well planned so as to avoid creating inadvertent tumour spread, and take into consideration any subsequent approaches for limb-sparing surgery.

Aims: To investigate the prevalence and significance of a high-intensity zone in a group of patients asymptomatic for low back pain.

Methods: A prospective observational study of the prevalence of abnormal MR imaging in normal volunteers without a significant history of back pain. All volunteers underwent physical examination, psychometric testing, plain radiograph, magnetic resonance imaging, and dexa scanning. Films were blindly assessed for the prevalence of degenerative disc disease, osteoporosis, high intensity zone, disc prolapse and spinal stenosis.

Results: Following history, clinical examination and psychometric testing 13 of 63 (20%) patients were excluded from the study on the basis of previous back injury, leg pain or abnormal clinical findings. 50 volunteers were eligible for inclusion in the study. The presence of a high-intensity zone or annular disruption was determined by standardised criteria on T2-wieghted magnetic resonance images. The prevalence of a high-intensity zone in the patient population was 12 of 50 patients (24%). 32% of all disc prolapses were at the L4/5 level, 33% were at L5/S1 and 17% were at L3/4 the remainder were at various other levels.

Conclusions: The presence of a high-intensity zone does not reliably indicate the presence of symptomatic internal disc disruption. Magnetic resonance imaging is accurate in determining nuclear anatomy, however positive findings do not always correlate with history and clinical findings. The presence of abnormal imaging in asymptomatic patients reinforces the need for a detailed history and clinical examination in the evaluation of the lumbar spine.

Aseptic loosening has become the single most important long-term complication of total joint replacements. The pathophysiology of this loosening is multifactorial in origin ranging from mechanical wear, poor surgical technique, thermal damage and the inflammatory response to particulate wear debris. Cytokines are released in response to macrophage activation by particulate wear debris (PWD), the resultant inflammatory cascade stimulates osteoclastic resorption of bone. The failure of remodelling and repair mechanisms may be as a result of Osteonecrosis from cement (PMMA).

Hypothesis: That PMMA increases Osteoblast susceptibility to necrosis and apoptosis following inflammatory challenge.

Materials and Methods: Osteoblast cell cultures were grown on PMMA cement plates and assessed for apoptosis and necrosis by PI exclusion staining, morphological changes on light and electron microscopy and flow cytometry.

Results: PMMA induced osteonecrosis is highest at 1 hour (34.45) in comparison to control levels (4.55). There is no significant change in Apoptosis at 24 hours. Culture of the Osteoblasts on cement and delayed stimulation with TNF-α causes increased Apoptosis and Necrosis.

Conclusion: PMMA cement causes Osteoblast necrosis in the early stages of polymerisation, after 24 hours there is little increase in apoptosis/necrosis. However Osteoblasts that grow in contact with cement are more susceptible to apoptosis and necrosis following TNFα challenge. This may prove to be an important step in the pathogenesis of Aseptic loosening.