Alignment
Conditions
Keywords
Total knee arthroplasty, Patient specific instruments, Patient matched cutting blocks, Alignment, Learning curve, VISIONAIRE
Brief summary
Description of logistics, learning curve and radiological results in 70 patients treated with patient specific instrumentation in total knee arthroplasty as a standard procedure
Detailed description
The Orthopaedic Clinic Gersthof is a teaching hospital, where the entire spectrum of joint replacements with emphasis on hips and knees is performed. Twenty surgeons perform TKAs at our institution, with approximately 400 TKAs implanted per year. The PSI system of Smith &Nephew® (Patient-Matched Cutting Blocks \[PMCB\]; the VISIONAIRE® technology) is applied. The preoperative image modality is based on a long leg standing X-ray as well as an MRI of the knee. The Genesis II® Endoprosthesis (Smith & Nephew®) is used as the TKA implant. This study is a observational monocentric prospective study. Estimated enrollment: 70 Enrollment time: September 2011-October 2012 Primary outcome: Alignment The postoperative X-rays (AP, lateral view, and long leg standing), taken 7-to-10 days after surgery are evaluated in terms of component position and restoration of the mechanical alignment. X-rays are routinely monitor-guided but not calibrated at our institution. As a secondary outcome the learning curve is evaluated using the following parameters collected during surgery: the fit of the cutting blocks, changes of the implant size, bony recuts, soft tissue releases, and changes in inlay size. Gap balancing was subjectively judged by the operating surgeon. Operation time, number of blood transfusions, and early postoperative complications were recorded within the first 14 days after surgery.
Interventions
DEVICETotal knee arthroplasty (TKA) (Smith &Nephew®)
Sponsors
Orthopedic Clinic Gersthof
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Indication for TKA * Genesis II endoprosthesis * Operated using patient specific instruments (VISIONAIRE)
Exclusion criteria
* contraindication for MRI * varus/ valgus deformity \>15 degrees
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Alignment | Postoperative x-ray (7-10 days after surgery) | Alignment measured on monitor-guided x-rays: Mechanical Alignment: Hip-Knee-Ankle angle in degrees \[°\] Alignment of the tibial and femoral component in the sagittal and coronal plane \[°\] |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Learning curve | Intraoperative and early postoperative period (up to 14 days after surgery) | In order to evaluate the learning curve associated with using VISIONAIRE® technology for TKA, the following parameters are registered during surgery: the fit of the cutting blocks\[subjective grading by the surgeon\], changes of the implant size\[number of changes\], bony recuts\[number of recuts\], soft tissue releases\[number of releases, kind of release\], and changes in inlay size \[number of inlay changes\]. Gap balancing is subjectively judged by the operating surgeon. Operation time\[minutes\], number of blood transfusions\[units\], and early postoperative complications associated with the treatment \[kind and number\] within the first 14 days after surgery are recorded. |
Countries
Austria
Outcome results
None listed