Introduction: Following successful introduction in 2007, all training programs except two participated in 2008. The examination was run along the principles of curriculum based, online delivery with immediate results and providing supportive information for the questions. The examination remains free of charge for the trainees and is supported by an educational grant from Depuy.

Material and methods: In 2008 a UKITE review board was appointed to create good quality questions with supportive information. We took on board the feedback from 2007 examination. Some questions from the 2008 examination were reported as ambiguous. The review board met and ambiguous questions were deleted from the examination and the scores recalculated.

Results: 648 trainees took UKITE 2008. Central organisation (86%) and local organisation (90%) were acceptable. 95% felt the examination pages were easy to use. There was difficulty in accessing the examination from NHS networks in some centers on the final day. 95% found there was educational benefit and 99% would like to sit again in 2009.

In the feedback from UKITE 2008, 85% of trainees felt it was better quality than 2007. The trainees approaching the FRCS examination are interested in using the database towards preparation.

In 2009 we aim to open the examination for SAS doctors, other surgical specialties and international trainees through elogbook.org.

Conclusion: UKITE has made progress in 2008. We aim to improve it further and open it to SAS doctors, other specialties and international trainees in 2009.

Background: There are no large comparative metal ion studies of commercially available hip resurfacing devices which have taken into account the effects of femoral size and cup inclination and anteversion.

Patients and methods: Metal ion analysis is carried out routinely at our independent centre. We present the metal ion results of 95 unilateral ASR patients and 70 unilateral BHR patients. For all patients, acetabular cup orientation was assessed using EBRA software. Patients with other metallic implants and those within 12 months of surgery were excluded.

Results: Whole blood/serum chromium (Cr) and cobalt (Co) concentrations were inversely related to femoral component size in both the ASR and BHR group (p< 0.05). Cr and Co levels were only seen to increase in the BHR group when the cup was implanted with an inclination greater than 55°. A significant relationship was identifed between the anteversion of the BHR cup and Cr and Co (p< 0.05 for Co, Spearman Rank correlation), with an increase in ions observed at anteversion angles > 17°. Cr and Co were more strongly influenced by cup position in the case of the ASR, with an increase in metal ions observed at inclinations greater than 45° and anteversion angles of < 10° and > 20°.

Discussion: The increased tolerance of the BHR cup to inclinations between 45–55° is likely due to the larger BHR cup providing greater protection against edge loading. When the cohort was divided by gender, the median Cr concentrations of the male ASR patients were significantly lower than those of the BHR males (p< 0.001). This suggests that in larger components positioned at more satisfactory angles of inclination and anteversion, the lower clearance of the ASR proves more significant than the extra coverage provided by the BHR cup. The BHR appears to be more sensitive to changes in anteversion than inclination.

There have been no large comparative studies of the blood levels of metal ions after implantation of commercially available hip resurfacing devices which have taken into account the effects of femoral size and inclination and anteversion of the acetabular component. We present the results in 90 patients with unilateral articular surface replacement (ASR) hip resurfacings (mean time to blood sampling 26 months) and 70 patients with unilateral Birmingham Hip Resurfacing (BHR) implants (mean time 47 months).

The whole blood and serum chromium (Cr) and cobalt (Co) concentrations were inversely related to the size of the femoral component in both groups (p < 0.05). Cr and Co were more strongly influenced by the position of the acetabular component in the case of the ASR, with an increase in metal ions observed at inclinations > 45° and anteversion angles of < 10° and > 20°. These levels were only increased in the BHR group when the acetabular component was implanted with an inclination > 55°.

A significant relationship was identified between the anteversion of the BHR acetabular component and the levels of Cr and Co (p < 0.05 for Co), with an increase observed at anteversion angles < 10° and > 20°. The median whole blood and serum Cr concentrations of the male ASR patients were significantly lower than those of the BHR men (p < 0.001). This indicates that reduced diametral clearance may equate to a reduction in metal ion concentrations in larger joints with satisfactory orientation of the acetabular component.

Purpose: Recent animal evidence has suggested that Bupivicaine may be harmful to articular cartilage. The purpose of this study was establish whether, following arthroscopy of the knee, infiltration of Bupivicaine around the portals is as effective as intra-articular infiltration for post-operative analgesia.

Method: Consecutive patients attending for knee arthroscopy were consented and randomised to one of two groups. Following arthroscopy, Group I received 20mls 0.5% Bupivicaine infiltrated into the joint; Group II received 20mls 0.5% Bupivicaine infiltrated around the portals. A Visual Analogue Score (VAS) was collected at one hour post-operatively and rescue analgesia recorded. A power calculation was performed. Ethical approval was granted.

Results: There were 68 patients in Group I (intra-articular) and 69 patients in Group II (portal). There was no significant difference in the age or sex distribution of patients in either group. The mean VAS score was 3.04 in Group I and 3.24 in Group II. There was no significant difference between the two groups (p=0.619). There was also no significant difference in the need for rescue analgesia (p=0.930). The study has demonstrated equivalence between the two groups, within one VAS point (Power = 80%).

Conclusion: We would recommend that following knee arthroscopy, Bupivicaine should be infiltrated around the portals, avoiding intra-articular infiltration.

The administration of intra-articular local anaesthetic is common following arthroscopy of the knee. However, recent evidence has suggested that bupivacaine may be harmful to articular cartilage. This study aimed to establish whether infiltration of bupivacaine around the portals is as effective as intra-articular injection.

We randomised 137 patients to receive either 20 ml 0.5% bupivacaine introduced into the joint (group 1) or 20 ml 0.5% bupivacaine infiltrated only around the portals (group 2) following arthroscopy. A visual analogue scale was administered one hour post-operatively to assess pain relief. Both patients and observers were blinded to the treatment group. A power calculation was performed.

The mean visual analogue score was 3.24 (sd 2.20) in group I and 3.04 (sd 2.31) in group 2. This difference was not statistically significant (p = 0.62).

Infiltration of bupivacaine around the portals had an equivalent effect on pain scores at one hour, and we would therefore recommend this technique to avoid the possible chondrotoxic effect of intra-articular bupivacaine.

Digital radiography is becoming widespread. Accurate pre-operative templating of digital images of the hip traditionally involves positioning a calibration object at its centre. This can be difficult and cause embarrassment. We have devised a method whereby a planar disc placed on the radiographic cassette accounts for the expected magnification. Initial examination of 50 pelvic CT scans showed a mean hip centre distance of 117 mm (79 to 142) above the gluteal skin. Further calculations predicted that a disc of 37.17 mm diameter, placed on the cassette, would appear identical to a 30 mm sphere placed at the level of the centre of the hip as requested by our templating software. We assessed accuracy and reproducibility by ‘reverse calibration’ of 20 radiographs taken three months after hip replacement using simultaneous sphere and disc methods, and a further 20 with a precision disc of accurate size. Even when variations in patient size were ignored, the disc proved more accurate and reliable than the sphere.

The technique is reliable, robust, cost effective and acceptable to patients and radiographers. It can easily be used in any radiography department after a few simple calculations and manufacture of appropriately-sized discs.

Purpose: to quantify the cost of hospitalisation and theatre time in the treatment of infected primary total knee replacements.

Materials and Methods: hospital approval was obtained for the study. Inclusion criteria were defined as: patients requiring surgery for deep or superficial infection of a primary total knee replacement (TKR) with subsequent positive bacteriological cultures. Clinical coding provided a list of patients with the ICD 10 code T845 (infection or inflammatory reaction due to an internal joint replacement) over a 2 year period and notes of patients were obtained to confirm the inclusion criteria were met. The theatre procedures performed and numbers of days in hospital for all admissions related to joint infection were recorded. The cost of a day in hospital and the cost of each procedure by time in minutes were obtained from the hospital finance department hence the overall cost of hospitalisation and theatre per patient estimated.

Results: 15 patients were identified as having undergone surgery for an infected primary TKR. Prolonged hospital stay, predominantly for administration of antibiotics claimed the largest proportion of expenditure in our patient group. An average of 64 excess days per patient were spent in hospital (range 13 to 218). The cost of an overnight hospital stay is £180, therefore the cost per patient was £11544. Seven day procedures at a cost of £473 each were also carried out. Each patient underwent an average of 4.7 theatre procedures (range 1 to 12). The most common surgical procedures were joint washout / debridement for early infection, joint aspiration, first and second stage revision. The cost of a minute of theatre time is £12.97, hence the cost of theatre time per patient was £4959. The overall estimated cost per patient for treatment of an infected primary total knee replacement is £16503 (exclusive of implant and antibiotic costs).

Conclusion: the cost of an infected TKR is a substantial financial burden for trusts as well as a catastrophic complication for patients. Methods of reducing expenditure include reduction in hospital stay by administration of antibiotics by district nurses or trained family members, rapid management of early joint infection by washout and debridement with the possibility of avoiding revision surgery and explantation of components upon diagnosis of bone/cement interface infection hence avoiding futile operations.

Aim: to compare the reliability of pre-operative templating for total hip and knee arthroplasty using printed digital radiographs versus conventional radiographs.

Materials and Methods: a prospective continuous study commenced January 2005. The PACS digital imaging system was introduced in May 2005 and the radiology department adopted a policy of printing orthopaedic radiographs to ‘true size’. All consultants and their registrars undertaking primary total hip and knee arthroplasty were asked to participate in the study and agreed. The operating surgeon completed a proforma for each Total Hip Replacement (THR) performed noting the templated cup and stem size and offset. Following the surgery the actual sizes and offset of the components implanted were also recorded on the proforma. A similar procedure was followed for the femoral and tibial components of Total Knee Replacements (TKR).

Results: there were 254 completed proformae. 186 pro-formae for conventional radiographs and 68 proformae for printed digital radiographs. Templating was possible from all the conventional radiographs; however templating was only possible from 58 of 68 (85%) digital radiographs as the images were obviously not true size. The templated sizes of both hip and knee components from conventional radiographs were more predictive of the actual size implanted in all cases. Furthermore there were a greater number of predicted outlying sizes using printed digital radiographs.

Conclusion: digital radiographs, even those said to be true size are unreliable for the purposes of pre-operative planning.

Introduction: There has been a renewed interest in metal-on-metal bearing for total hip replacement with the benefit of a larger head size and decreased incidence of dislocation. In the revision hip scenario cementation of a polyethylene liner, for a previously compromised liner fixation mechanism into a preexisting well-fixed shell or a cage, has become an accepted method to decrease the morbidity of the procedure. Perhaps Bir-mingham cementless cups could be used as cemented devices in primary and revision hip surgery where a cementless cup is not possible.

Aim: To study the pull-out strength of cemented Bir-mingham sockets in an experimental model.

Materials and Methods: Eight Birmingham cups were cemented into wooden blocks after they were reamed to the appropriate size allowing for a 3mm cement mantle, multiple holes drilled into the reamed sockets and cement vacuum-mixed. Cable was then threaded through the holes on the rim of the cup and the wooden block was then mounted on a metal plate and secured. Linear tension was then gradually applied on the cup through the cable.

Results: The pull-out strength of the cemented Birming-ham cups was higher than the failure of the cable. The tensile load to failure for the cables ranged from 3642.6 N to 4960 N with an average load of 4286.9 N.

Conclusion: The average tensile load of 4286.9 is very high compared to previous studies with cemented poly-ethylene and metal liners. This finding is very promising and might support clinical application in complex primary and revision total hip replacement.

Introduction: Aseptic loosening is the commonest complication of cemented total hip arthroplasy. Gaseous voids within the cement mantle are thought to act as stress concentrators and points of origin and preferential fracture propagation at the cement stem interface. Assuming a bone tempereature of 37°C, Bishop recommended heating the prosthesis to 44°C, thereby effecting a reduction in cement-prosthesis interface porosity.

The aim of this study was to (I) determine the intra-operative temperature of the femoral cancellous bed prior to insertion of prosthesis, (II) to investigate whether the magnitude of the temperature gradient effects interface porosity (III) to develop clinically relevant recommendations.

Materials and Methods: (I) The intra-operative determination of femoral cancellous boney bed temperature. Sterile, single use thermocouples (Mon-a-therm) were used to record interface temperature in six patients, after canal preparation and lavage. (II) A simulated femoral model was designed consisting of a waterbath, set at temperature determined by (I) with an inner water-tight chamber formed by 19mm diameter polyethylene tubing. Cement (Palacos) was non-vacuum mixed (to exaggerate porosity) for 1 minute and injected in a retrograde manner into the inner tube at 3 minutes. Femoral stems (Exeter) were pre-heated in a second waterbath to 18, 32,35,37,40,44°C, were thoroughly dried and lowered into the inner tube by a Lloyd universal testing machine via a custom jig. The cement was left to polymerise.

The cement mantle was sectioned transversely, then longitudinally to expose the cement-prosthesis interface. This was stained with acrylic dye to facilitate image analysis. Three mantles for each temperature were produced.

Results: (I) The mean femoral canal temperature was 32.3°C, (II) the effect of stem temperature on interface porosity is shown in fig1.

Conclusions: Bone temperature is 32°C after canal preparation using contemporary cementing techniques. Heating to 35°C reduces interface porosity, heating to 40°C is optimal.

To determine whether resection of osteophyte at TKR improves movement, 139 TKRs were performed on knees with pre-operative posterior osteophyte. Randomisation was to have either resection of distal femoral osteophyte guided by a custom made ruler or no resection. After preparation of the femoral bone cuts the ruler measuring 19 mm was placed just proximal to the posterior chamfer cut. The proximal end of this ruler marked the bone to be resected and this was performed using an osteotome at 45 degrees. Knees randomised to no resection had no further femoral bony cuts. Three months after implantation the patients had range of motion assessed.

One hundred and fourteen suitable knees were assessed, with 59 knees (57 patients) in the resection group and 55 knees (54 patients) in the no resection group. Full extension was more likely in the resection group (62%) than the group without resection (41%)(p=0.08). Flexion to at least 110 degrees was, however, less in the resection group (37%) than the no resection group (54%) (p=0.09).

Our study failed to show a statistically significant difference if the bony osteophyte is removed. There were however sharp trends, with statistically a one in ten chance these results would be different if the trial was repeated. Although there is no indication as to the cause of improved extension this could be explained by the release of the posterior capsular structures allowing full extension. The reduction in flexion is harder to explain and this may be due to increase in perioperative trauma and resultant swelling, possibly with fibrosis. Range of movement, particularly flexion, is known to improve up to 1 year post-operatively and assessment of these groups at that stage would be beneficial.

The aim of this study was to establish the ability of an invasive fibre-optic probe to measure intra-muscular pH, pCO₂, pO₂, HCO₃-⁻, ambient temperature, base excess and O₂ saturation. The secondary aim was to determine the effect of elevation of the limb on these parameters.

Fibre-optic probes were introduced into the anterior compartment muscle of the leg in five volunteers via 16G cannulae. After equilibration the limb was monitored for 11min with the volunteer supine on an examination couch. The limb was elevated to 22cm (Braun frame) and then 44cm for the same time. Subsequently the leg was returned to 22cm and supine. All volunteers followed this set protocol. Continuous recording of all indices was made throughout. Data was stored to a personal computer for analysis.

Similar trends were observed across all subjects for all parameters. The mean pO₂ when lying flat was 27mmHg (S.D.7.4). Elevation to 22cm increased muscle pO₂ to 33 mmHg (S.D. 5.8). Further elevation to 44 cm resulted in a reduction in muscle pO₂ to a level below that measured when supine. When the limb was returned to 22cm the pO2 trend reversed, the level improving. Returning to the supine position the pO₂ returned to the level seen at the start of monitoring.

This novel probe gives reproducible measures of pH, pCO₂, pO₂, HCO₃⁻, ambient temperature, base excess and O₂ saturation. Results indicate that elevation to 22cm improves muscle oxygenation; a height of 44cm seems detrimental. This technique may be applicable in surveillance for compartment syndromes and muscle ischaemia.