EVALUACIÓN DE INICIO EN COMPRENSIÓN LECTORA DEL GRUPO DE

resections, Catani et al. [9] measured the alignment of the bone resections

during surgery. The alignment measure was repeated after final tibial and

femoral component implantation with cement. The alignment deviation

was >1° in the frontal plane of the femur in 20%. However, the rotational position was not evaluated and the influence of the thickness of the cement

layer on femoral component position is therefore still unknown. Thus, the positioning of the components in total knee arthroplasty, which mainly

involves cementation and impaction of the final components, can introduce

an error in alignment, regardless of how accurately the resection planes are made.

In conclusion, the intraoperative CAOS measured rotation of the femoral

component differs from the postoperative CT measured position and

is therefore not reliable as an absolute value. CAOS can probably help to achieve the optimal position of the femoral component but continuous improvement in methods to accurately identify the rotational position and establish the ideal rotation of the components in total knee arthroplasty is still needed.

Reference List

1. Akagi M, Matsusue Y, Mata T, Asada Y, Horiguchi M, Iida H, Nakamura T (1999) Effect of rotational alignment on patellar tracking in total knee arthroplasty. Clin Orthop Relat Res 366:155–163.

2. Barrack RL, Schrader T, Bertot AJ, Wolfe MW, Myers L (2001) Component rotation and anterior knee pain after total knee arthroplasty. Clin Orthop Relat Res 392:46–55. 3. Bauwens K, Matthes G, Wich M, Gebhard F, Hanson B, Ekkernkamp A, Stengel D (2007)

Navigated total knee replacement. A meta-analysis. J Bone Joint Surg Am 89:261–269. 4. Benjamin J (2008) Determining femoral component position using CAS and measured

resection. Clin Orthop Relat Res 466:2745–2750.

5. Berger RA, Crossett LS, Jacobs JJ, Rubash HE (1998) Malrotation causing patellofemoral complications after total knee arthroplasty. Clin Orthop Relat Res 356:144–153 Interna- tional Orthopaedics (SICOT).

6. Bland JM, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement. Lancet 1:307–310.

7. Boisgard S, Moreau PE, Descamps S, Courtalhiac C, Silbert H, Moreel P, Michel JL, Levai JP (2003) Computed tomographic study of the posterior condylar angle in arthritic knees: its use in the rotational positioning of the femoral implant of total knee prostheses. Surg Radiol Anat 25:330–334.

8. Boldt JG, Stiehl JB, Munzinger U, Beverland D, Keblish PA (2006) Femoral component rotation in mobile-bearing total knee arthroplasty. Knee 13:284–289.

9. Catani F, Biasca N, Ensini A, Leardini A, Bianchi L, Digennaro V, Giannini S (2008) Align- ment deviation between bone resection and final implant positioning in computer-navi- gated total knee arthroplasty. J Bone Joint Surg Am 90:765–771.

10. Chauhan SK, Clark GW, Lloyd S, Scott RG, Breidahl W, Sikorski JM (2004) Computer- assisted total knee replacement. A controlled cadaver study using a multi-parameter quantitative CT assessment of alignment (the Perth CT Protocol). J Bone Joint Surg Br 86:818–823.

11. Chauhan SK, Scott RG, Breidahl W, Beaver RJ (2004) Computerassisted knee arthroplasty versus a conventional jig-based technique. A randomised, prospective trial. J Bone Joint Surg Br 86:372–377.

12. Decking R, Markmann Y, Fuchs J, Puhl W, Scharf HP (2005) Leg axis after computer-navi- gated total knee arthroplasty: a prospective randomized trial comparing computer-navi- gated and manual implantation. J Arthroplasty 20:282–288.

13. Galaud B, Beaufils P, Michaut M, Abadie P, Fallet L, Boisrenoult P (2008) Distal femoral torsion: comparison of CT scan and intra operative navigation measurements during total knee arthroplasty. Rev Chir Orthop Reparatrice Appar Mot 94:573–579.

14. Han HS, Seong SC, Lee S, Lee MC (2006) Rotational alignment of femoral components in total knee arthroplasty: nonimage-based navigation system versus conventional tech- nique. Orthopedics 29: S148–S151.

5

15. Jazrawi LM, Birdzell L, Kummer FJ, Di Cesare PE (2000) The accuracy of computed to- mography for determining femoral and tibial total knee arthroplasty component rota- tion. J Arthroplasty 15:761–766.

16. Kamat YD, Aurakzai KM, Adhikari AR, Matthews D, Kalairajah Y, Field RE (2009) Does computer navigation in total knee arthroplasty improve patient outcome at midterm follow-up? Int Orthop 33:1567–1570.

17. Landis JR, Koch GG (1977) An application of hierarchical kappatype statistics in the as- sessment of majority agreement among multiple observers. Biometrics 33:363–374. 18. Laskin RS (1995) Flexion space configuration in total knee arthroplasty. J Arthroplasty

10:657–660.

19. Matziolis G, Krocker D, Weiss U, Tohtz S, Perka C (2007) A prospective, randomized study of computer-assisted and conventional total knee arthroplasty. Three-dimensional evalu- ation of implant alignment and rotation. J Bone Joint Surg Am 89:236–243.

20. Michaut M, Beaufils P, Galaud B, Abadie P, Boisrenoult P, Fallet L (2008) Rotational align- ment of femoral component with computed-assisted surgery (CAS) during total knee ar- throplasty. Rev Chir Orthop Reparatrice Appar Mot 94:580–584.

21. Mullaji A, Kanna R, Marawar S, Kohli A, Sharma A (2007) Comparison of limb and compo- nent alignment using computerassisted navigation versus image intensifier-guided con- ventional total knee arthroplasty: a prospective, randomized, single-surgeon study of 467 knees. J Arthroplasty 22:953–959.

22. Oberst M, Bertsch C, Wurstlin S, Holz U (2003) CT analysis of leg alignment after conven- tional vs. navigated knee prosthesis implantation. Initial results of a controlled, prospec- tive and randomized study. Unfallchirurg 106:941–948.

23. Poilvache PL, Insall JN, Scuderi GR, Font-Rodriguez DE (1996) Rotational landmarks and sizing of the distal femur in total knee arthroplasty. Clin Orthop Relat Res 331:35–46. 24. Sharkey PF, Hozack WJ, Rothman RH, Shastri S, Jacoby SM (2002) Insall award paper.

Why are total knee arthroplasties failing today? Clin Orthop Relat Res 404:7–13. 25. Siston RA, Patel JJ, Goodman SB, Delp SL, Giori NJ (2005) The variability of femoral rota-

tional alignment in total knee arthroplasty. J Bone Joint Surg Am 87:2276–2280. 26. Sparmann M, Wolke B, Czupalla H, Banzer D, Zink A (2003) Positioning of total knee ar-

throplasty with and without navigation support. A prospective, randomised study. J Bone Joint Surg Br 85:830–835.

27. Stiehl JB (2009) Comparison of tibial rotation in fixed and mobile bearing total knee ar- throplasty using computer navigation. Int Orthop 33:679–685.

28. Stockl B, Nogler M, Rosiek R, Fischer M, Krismer M, Kessler O (2004) Navigation im- proves accuracy of rotational alignment in total knee arthroplasty. Clin Orthop Relat Res 426:180–186.

29. Suter T, Zanetti M, Schmid M, Romero J (2006) Reproducibility of measurement of femo- ral component rotation after total knee arthroplasty using computer tomography. J Ar- throplasty 21:744–748.

30. Van der Linden-van der Zwaag HM, Valstar ER, van der Molen AJ, Nelissen RG (2008) Transepicondylar axis accuracy in computer assisted knee surgery: a comparison of the CT-based measured axis versus the CAS-determined axis. Comput Aided Surg 13:200– 206.

31. Van Strien T, van der Linden-van der Zwaag HM, Kaptein B, van Erkel A, Valstar E, Nelis- sen RG (2009) Computer assisted versus conventional cemented total knee prostheses alignment accuracy and micromotion of the tibial component. Int Orthop 33:1255–1261. 32. Whiteside LA, Arima J (1995) The anteroposterior axis for femoral rotational alignment in

valgus total knee arthroplasty. Clin Orthop Relat Res 321:168–172.

33. Yau WP, Leung A, Chiu KY, Tang WM, Ng TP (2005) Intraobserver errors in obtaining visu- ally selected anatomic landmarks during registration process in nonimage-based naviga- tion-assisted total knee arthroplasty: a cadaveric experiment. J Arthroplasty 20:591–601.