Preoperative and Postoperative Comparisons of Navigation and Radiologic Limb Alignment Measurements After High Tibial Osteotomy


      To determine whether navigation-assisted intraoperative lower limb alignment in open wedge high tibial osteotomy (HTO) correlates with preoperative and postoperative radiographic alignment.


      This prospective study involved 35 patients (39 knees) who underwent navigation HTO for primary medial osteoarthritis. The mechanical axis (MA) and weight-bearing line (WBL) ratio were calculated from preoperative radiographs, intraoperative navigation, and postoperative (6 months) radiographs. Reliability between navigation and radiographic alignment was analyzed by use of intraclass correlation coefficients (ICCs) with thresholds as follows: good, greater than 0.75; fair, 0.4 to 0.75; and poor, less than 0.4. The surgical target for the MA was a final valgus overcorrection of 2° to 8°, and the WBL ratio target was between 50% and 70%. Outliers for differences between intraoperative navigation and postoperative radiographic results were defined as greater than ±3° for the MA and greater than ±10% for the WBL ratio.


      The MA target was achieved in 33 of 39 knees (84.6%), and the WBL ratio target was achieved in 30 of 39 knees (74.4%). ICCs for navigational reliability were good for preoperative MA and WBL ratio and fair for postoperative MA and WBL ratio. The ICCs for the MA were better than those for the WBL ratio for both preoperative and postoperative measurements. The differences between the number of outliers between the navigation and radiographic MA and WBL were greater postoperatively than preoperatively. In addition, the postoperative differences in the extent of the outliers between navigation and radiographic measurements were greater for WBL ratios than the MA (P = .023).


      This study found that use of a navigation system achieved the target value for MA lower limb correction in over 80% of open wedge HTO cases, using radiographic data as the gold standard for alignment. Because the navigational measurements of lower limbs during open wedge HTO did not correlate with postoperative radiographic alignment, corrections should not be based solely on navigational results. In assessing the reliability of navigational open wedge HTO for correction of lower limb alignment, the MA is a better radiologic parameter than the WBL ratio.

      Level of Evidence

      Level IV, therapeutic case series.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Arthroscopy
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Hankemeier S.
        • Mommsen P.
        • Krettek C.
        • et al.
        Accuracy of high tibial osteotomy: Comparison between open- and closed-wedge technique.
        Knee Surg Sports Traumatol Arthrosc. 2010; 18: 1328-1333
        • Noyes F.R.
        • Mayfield W.
        • Barber-Westin S.D.
        • Albright J.C.
        • Heckmann T.P.
        Opening wedge high tibial osteotomy: An operative technique and rehabilitation program to decrease complications and promote early union and function.
        Am J Sports Med. 2006; 34: 1262-1273
        • DeMeo P.J.
        • Johnson E.M.
        • Chiang P.P.
        • Flamm A.M.
        • Miller M.C.
        Midterm follow-up of opening-wedge high tibial osteotomy.
        Am J Sports Med. 2010; 38: 2077-2084
        • Bachhal V.
        • Sankhala S.S.
        • Jindal N.
        • Dhillon M.S.
        High tibial osteotomy with a dynamic axial fixator: Precision in achieving alignment.
        J Bone Joint Surg Br. 2011; 93: 897-903
        • Hankemeier S.
        • Hufner T.
        • Wang G.
        • et al.
        Navigated open-wedge high tibial osteotomy: Advantages and disadvantages compared to the conventional technique in a cadaver study.
        Knee Surg Sports Traumatol Arthrosc. 2006; 14: 917-921
        • Akamatsu Y.
        • Mitsugi N.
        • Mochida Y.
        • et al.
        Navigated opening wedge high tibial osteotomy improves intraoperative correction angle compared with conventional method.
        Knee Surg Sports Traumatol Arthrosc. 2012; 20: 586-593
        • Kim S.J.
        • MacDonald M.
        • Hernandez J.
        • Wixson R.L.
        Computer assisted navigation in total knee arthroplasty: Improved coronal alignment.
        J Arthroplasty. 2005; 20: 123-131
        • Mason J.B.
        • Fehring T.K.
        • Estok R.
        • Banel D.
        • Fahrbach K.
        Meta-analysis of alignment outcomes in computer-assisted total knee arthroplasty surgery.
        J Arthroplasty. 2007; 22: 1097-1106
        • Tingart M.
        • Lüring C.
        • Bäthis H.
        • Beckmann J.
        • Grifka J.
        • Perlick L.
        Computer-assisted total knee arthroplasty versus the conventional technique: How precise is navigation in clinical routine?.
        Knee Surg Sports Traumatol Arthrosc. 2008; 16: 44-50
        • Pearle A.D.
        • Goleski P.
        • Musahl V.
        • Kendoff D.
        Reliability of image-free navigation to monitor lower-limb alignment.
        J Bone Joint Surg Am. 2009; 91: 90-94
        • Goleski P.
        • Warkentine B.
        • Lo D.
        • Gyuricza C.
        • Kendoff D.
        • Pearle A.D.
        Reliability of navigated lower limb alignment in high tibial osteotomies.
        Am J Sports Med. 2008; 36: 2179-2186
        • Kendoff D.
        • Board T.N.
        • Citak M.
        • et al.
        Navigated lower limb axis measurements: Influence of mechanical weight-bearing simulation.
        J Orthop Res. 2008; 26: 553-561
        • Shrout P.E.
        • Fleiss J.L.
        Intraclass correlations: Uses in assessing rater reliability.
        Psychol Bull. 1979; 86: 420-428
        • Bae D.K.
        • Song S.J.
        • Yoon K.H.
        Closed-wedge high tibial osteotomy using computer-assisted surgery compared to the conventional technique.
        J Bone Joint Surg Br. 2009; 91: 1164-1171
        • Kim S.J.
        • Koh Y.G.
        • Chun Y.M.
        • Kim Y.C.
        • Park Y.S.
        • Sung C.H.
        Medial opening wedge high-tibial osteotomy using a kinematic navigation system versus a conventional method: A 1-year retrospective, comparative study.
        Knee Surg Sports Traumatol Arthrosc. 2009; 17: 128-134
        • Lützner J.
        • Gross A.F.
        • Günther K.P.
        • Kirschner S.
        Precision of navigated and conventional open-wedge high tibial osteotomy in a cadaver study.
        Eur J Med Res. 2010; 15: 117-120
        • Liodakis E.
        • Chu K.
        • Westphal R.
        • et al.
        Assessment of the accuracy of infrared and electromagnetic navigation using an industrial robot: Which factors are influencing the accuracy of navigation?.
        J Orthop Res. 2011; 29: 1476-1483
        • Gebhard F.
        • Krettek C.
        • Hüfner T.
        • et al.
        Reliability of computer-assisted surgery as an intraoperative ruler in navigated high tibial osteotomy.
        Arch Orthop Trauma Surg. 2011; 131: 297-302
        • Sim J.A.
        • Kwak J.H.
        • Yang S.H.
        • Choi E.S.
        • Lee B.K.
        Effect of weight-bearing on the alignment after open wedge high tibial osteotomy.
        Knee Surg Sports Traumatol Arthrosc. 2010; 18: 874-878
        • Lee D.H.
        • Padhy D.
        • Lee S.H.
        • Nha K.W.
        • Park J.H.
        • Han S.B.
        Osteoporosis affects component positioning in computer navigation-assisted total knee arthroplasty.
        Knee. 2012; 19: 203-207
        • Kawakami H.
        • Sugano N.
        • Yonenobu K.
        • et al.
        Effects of rotation on measurement of lower limb alignment for knee osteotomy.
        J Orthop Res. 2004; 22: 1248-1253
        • Kendoff D.
        • Citak M.
        • Pearle A.
        • et al.
        Influence of lower limb rotation in navigated alignment analysis: Implications for high tibial osteotomies.
        Knee Surg Sports Traumatol Arthrosc. 2007; 15: 1003-1008