Abstract
Alignment and soft tissue balance are two of the most important factors that influence early and long term outcome of total knee arthroplasty.
Current clinical practice involves the use of plain radiographs for preoperative planning and conventional instrumentation for intra operative alignment.
The aim of this study is to assess the SignatureTM Personalised system using patient specific guides developed from MRI. The SignatureTM system is used with the VanguardRComplete Knee System. This system is compared with conventional instrumentation and computer assisted navigation with the Vanguard system.
Patients were randomised into 3 groups of 50 to either Conventional Instumented Knee, Computer Navigation Assisted Knee Arthroplasty or Signature Personalised Knee Arthoplasty. All patients had the Vanguard Total knee Arthroplasty Implanted.
All patients underwent Long leg X-rays and CT Scans to measure Alignment at pre-op and 6 months post-op. All patients had clinical review and the Knee Society Score (KSS) at 1 year post surgery was used to measure the outcome.
A complete dataset was obtained for 124 patients. There were significant differences in alignment on Long leg films ot of CT scan with perth protocol. Notably the Signature group had the smallest spread of outliers.
In conclusion the Signature knee system compares well in comparison with traditional instrumentation and CAS Total Knee Arthroplasty.