Three different cruciate sacrificing TKA designs: no intraoperative kinematic differences and no clinical differences at 2 years follow up.

Bruni D, Bignozzi S, Zaffagnini S, Akkawi I, Marko T, Gagliardi M, Colle F, Marcacci M.

Rizzoli Orthopaedic Institute – Bologna, Italy

Sparmann et al 2003Amiot et al 2004Decking et al 2005Saragaglia et al 2001Jenny et al 2001Kim et al 2005Anderson et al 2005Novak et al 2007

Sparmann et al 2003Amiot et al 2004Decking et al 2005Saragaglia et al 2001Jenny et al 2001Kim et al 2005Anderson et al 2005Novak et al 2007

Chauhan et al 2004Martin et al 2005Decking et al 2005Matziolis et al 2007Kim et al 2007Kalairajah et al 2007

Chauhan et al 2004Martin et al 2005Decking et al 2005Matziolis et al 2007Kim et al 2007Kalairajah et al 2007

Perlick et al 2004Haaker et al 2005Chauahan et al 2004Bathis et al 2004Matziolis et al. 2007

Perlick et al 2004Haaker et al 2005Chauahan et al 2004Bathis et al 2004Matziolis et al. 2007

Better limb alignment Better implant positioning

Comparable surgical times

Less blood loss

Why using Navigation system?

Brin, Int Orthop 2010Biasca, Orthop Clin North Am. 2009 Dorr, Orthopedics. 2009 Berend ME. Orthopedics. 2009 Dattani R. Int Orthop. 2009 Sikorski JM. Jbjs Br. 2008 Mason JB, J Arthroplasty. 2007 Claus A, Orthopade. 2007 Briard JL, Orthopade. 2007 Siston RA, J Biomech. 2007 Laskin RS CORR. 2006

Clinical efficacy has not yet been demonstrated

1/4 patients in USA,UK & Canada are not satisfied

Regardless of whether CAS or conventional

Can we use navigation system to evaluate intraoperative clinical and functional differences in different

implants?

Materials and Methods

“3° Condyle“- MB (CS) ULTRACONGRUENT-MB (AS) SPINE CAM-MB (PS)

90 patients with primary OA

Average age at surgery: 70 years (57-85)

Randomized distribution into 3 groups of cruciate sacrificing TKA

Intraoperative kinematics acquisition:

PROM: passive range of motion, (0°-120°) AP90: Drawer test at 90 ° of flexion, exerting maximum force VV Stress Test at 0° and 30° Test repeated 3 times

Materials and methods

Clinical evaluation using standardized scores: WOMAC [1], KSS-f [2], SF-36 [3]

 [2] Insall JN, Dorr LD, Scott RD, Scott WN. Rationale of the Knee Society clinical rating system. Clin Orthop Relat Res. 1989 Nov;(248):13-4.

 [1] Roos EM, Roos HP, Lohmander LS, Ekdahl C, Beynnon BD. Knee Injury and Osteoarthritis Outcome Score (KOOS)--development of a self-administered outcome measure. J Orthop Sports Phys Ther. 1998 Aug;28(2):88-96.

[3] Ware JE Jr, Sherbourne D. The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection. Med Care 1992 Jun;30(6):473-83.

Under stress VV Laxity at 0° e 30°

Laxity reduction VV 0°:-3,1° ’’3rd CONDYLE’’-2,4° ULTRACONGRUENT-MB-2,3° SPINE CAM-MB

Laxity reduction VV 30°:-0° ’ ’3rd CONDYLE’’-1,1° ULTRACONGRUENT-MB-1,1° SPINE CAM-MB

Significative reduction at 0° (p=0.006)

Not significant at 30°

No statistical differences between the three models

«3° condyle» -MB ULTRACONGRUENT-MB (AS) SPINE CAM-MB

Under stress AP 90 laxity

2mm of laxity reduction for ‘’3° CONDYLE’’ model (p=0.007)

4.9mm of laxity increase for ULTRACONGRUENT-MB model (p=0.008)

5mm of laxity increase for SPINE CAM-MB model (p=0.008)

«3° condyle» -MB ULTRACONGRUENT-MB (AS) SPINE CAM-MB

Under stress AP 90 Laxity

Internal (-) and External (+) tibial rotation during flexion

Postoperative reduction of Internal rotation in all 3 models

More stable pattern for SPINE CAM-MB e ’’3rd Condyle’’

B) “3° CONDYLE“- MB

C) ULTRACONGRUENT-MB

A) SPINE-CAM MB

NOT statistically significant

AP translation (mm)Of femoral epicondyles during flexion

Slightly better pattern in SPINE CAM-MB

C) ULTRACONGRUENT-MB

B) “3rd CONDYLE“- MB

A) SPINE-CAM MB

NOT statistically significant

Clinical results

CONCLUSIONS

Reduction of tibial internal rotation after surgery, increased posterior translation of the femoral epicondyles in all three models

Better AP stability was noticed in ‘’3rd condyle’’ model

No significant differences in clinical score at 2 years in all 3 models

Thank you for your attention