Arthroplasty performed for the partial or complete resurfacing, remodelling or replacement of a degenerative or dysfunctional joint is a common procedure. The number of total knee and hip arthroplasty procedures performed per year are increasing with the number of total knee arthroplasties (TKA) predicted to more than double by 2030. Although this provides dramatic relief from pain, these implants do have a limited lifespan.

Approximately 10% of total hip arthroplasty (THA) implants require revision due to periprosthetic osteolysis. Approximately 40% require revision due to aseptic loosening believed to be due to polyethylene wear. Arthroplasty prostheses may also fail due to deep infection, malpositioned or oversized implants and peri-prosthetic fractures. It is difficult to predict which patients will develop complications. Therefore follow up has typically involved serial clinical and radiographic assessments for the lifetime of the patient. Despite many collective years of experience there is still disparity in the follow-up of such patients. Elective arthroplasty forms the major bulk of workload in trauma and orthopaedic surgery. Efficient service provision and planning requires an agreed, evidence-based protocol. Currently no consensus exists, however there are many papers detailing the effectiveness of imaging techniques as well as the need for timed clinical assessments.

The authors review current literature regarding hip and knee arthropalsty procedures, potential causes of failure and methods of detection in order to highlight areas of potential future research to enable an evidence-based protocol to be derived.

Aims

Revision total hip arthroplasty is a common operation. The MP Link (Waldemar Link, Hamburg, Germany) system is a distally loading, modular, tapered femoral stem component for revision hip surgery. MP Link in revision total hip arthoplasty was investigated clinically, radiologically and with Oxford hip scores.

Introduction: Obesity [Body Mass Index (BMI) > 30] is seen in a growing percentage of patients seeking joint replacement surgery. Recent studies have shown no clear influence of obesity on the five-year, clinical outcome of total knee replacement; except for the morbidly obese (BMI > 40). Computer navigation has shown improved consistency of prosthetic component alignment. However, this aid does significantly increase operation time.

Aims:

To compare tourniquet times of standard and computer assisted total knee arthroplasty in patients with BMI more than 30

Methods and Results: A retrospective analysis of 82, obese, total knee replacements performed by a single surgeon, at a dedicated arthroplasty centre, was undertaken. Conventional knee replacement instrumentation (Plus Orthopaedics, UK) was used in 42 cases and computer assisted navigation (Galileo- Plus Orthopaedics) in 39 cases. The patients were divided into three equal sized groups (1, 2 & 3), in chronological order. Each group comprised fourteen knees undertaken using standard surgical technique and thirteen knees using computer assisted navigation.

Group1 had average tourniquet times of 95.69 and 111.67 minutes in the standard and computer assisted groups respectively (p 0.01). Group 2 tourniquet times were 80.75 and 92.33 minutes (p 0.05). Group 3 tourniquet times were 84.5 and 87.5 minutes; these were not significantly different.

Conclusions: As the surgeon acquired experience of computer assisted navigation, his tourniquet times decreased and by the end of our study period, there was no longer any difference between the tourniquet times for conventional and computer assisted knee replacement in this subgroup of obese patients. We hypothesise that in obese patients, computer assisted navigation helps the surgeon to overcome jig alignment uncertainty and thus improves accuracy of component alignment without any significant time penalty.

Introduction: Measurement of outcome after THR is becoming increasingly important. NICE guidelines have been established and ODEP have stipulated target criteria for the successful evaluation of novel implants. To date, a streamlined, efficient Outcome Programme has not been developed which satisfies the required follow-up criteria. A Programme has been developed at our unit and its evolution is reported.

Methods: A database was created with the assistance of a database developer and an “Outcome Co-ordinator” was appointed to operate the database and manage the programme.

Operation data is now entered onto the database by the surgeon or co-ordinator at the time of surgery. Thereafter, the database automatically produces annual Oxford Hip Questionnaires, EQ-5D questionnaires and invite letters to patients for clinical review at stipulated time-points.

Questionnaires are returned by patients and scanned. This data is then electronically imported to the database without transcription error. Patients attend special Outcome clinics, staffed by Research Fellows and SpR’s, who examine the relevant hip and review their radiographs. The findings are recorded and the paper forms scanned and imported into the database. Non-responders are identified from the database and are chased up via telephone by the coordinator.

Data is extracted from the database with queries and presented using database reports.

Results: 2455 THR’s have been recorded on the database (2127 primaries, 328 revisions) 1937 patients continue under active review for THR. The percentage of patients lost to follow-up is only 2%, 10%, 15% at 2, 5 and 10 years respectively.

Discussion: An efficient system has been developed to maximise the follow-up of patients post THR. The burden on outpatient clinics is reduced and meaningful outcome measures are obtained. The programme could easily be extended to other centres throughout the UK and the benchmarks set by ODEP and NICE can also be attained.