Cesare Chemello
Asiago Hospital, Italy
Title: PSI: new instruments for a new generation of knee arthroplasty
Biography
Biography: Cesare Chemello
Abstract
Introduction: Custom Made Surgery seems to be the future of total knee replacement (TKR). “Patients specific instrument” (PSI) helps the surgeon to perform a real tissue sparing surgery (TSS) and it allows to customize the technique and to standardize the results. Usually rheumatologic knees have important axial deviation and important bone loss, for this reason it is difficult to use a traditional prosthesis. The aim of our study was to illustrate the advantages and disadvantages of PSI in a prospective study of 100 pre-navigated total knee replacements.
Materials & Methods: 100 patients, affected by knee advance osteoarthritis and by axial deviation exceeding 3°, underwent to TKR (Advance Prophecy Wright). In the pre-operative examination, a TC was performed following strict protocols. We used a strict radiological protocol Post operative axes were compared to the planed ones and the following angles were examined: between anatomical and mechanical femoral axis (α-AAM), femoral flexion shield (FSF), tibial slope (ST) and frontal angle of the tibial component (α-CT). Negative outcome was considered as axial deviations ± 2 for FSF, ST and ±3 for α-CT e α-AAM.
Results: All patients achieved an excellent clinical and functional result according to KSS. Unplanned gender prosthesis was implanted in two patients. In only 1 case we changed the component size (femoral). In two cases, a 17 mm insert was necessary. Final knee flexion was necessary always more than 105°. Only 2 errors of the final α-AAM
Conclusion: This technique allows performing a TSS surgery, to reduce surgical time, to obtain optimal alignments. This technique also allows converting a challenging knee in a normal knee.