SAFE ZONE OF JOINT LINE ELEVATION FOR THE TREATMENT OF KNEE FLEXION CONTRACTURE PREVENTING MID-FLEXION INSTABILITY IN TOTAL KNEE REPLACEMENT

Authors

  • Nauman Abbas Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan
  • Sabir Khan Khattak Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan
  • Muhammad Umer Faheem Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan
  • Naeem Ahmed Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan
  • Amer Aziz Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan
  • Latif Khan Department of Orthopaedics, Ghurki Trust & Teaching Hospital, Lahore-Pakistan

DOI:

https://doi.org/10.55519%20JAMC-02-13141

Keywords:

Total knee arthroplasty (TKA); Joint line elevation (JLE); Mid-flexion instability (MFI); Posterior stabilized (PS) knee

Abstract

Background: In osteoarthritic knee, flexion deformity is caused by synovial inflammation, posterior femoral and tibial osteophytes tenting onto the capsule, ligamentous contracture and hamstring shortening. This study aimed to evaluate the safe zone of joint line elevation for the treatment of flexion knee contracture preventing mid-flexion instability in total knee replacement. Methods 51 knees with varus osteoarthritis undergoing TKA were evaluated. 39 knees with flexion contracture < 15°and 12 knees with flexion contracture >15°.  2-mm joint line elevation was performed in just 4 knees with >15° flexion contracture. The extension and flexion gaps were measured with traditional spacer block. Stability in coronal plane (varus & valgus stress) was assessed at 0,30,60 & 90 degrees. Sampling Technique was non probability consecutive. SPSS 23 was used for statistical analysis. Results: The study comprises 51 patients undergoing total knee replacement (TKA) for osteoarthritis, with a notable gender distribution (84.3% women, 15.7% men) and a mean age of 60.24±8.54 years. Of these, 41.2% had both knees affected, and joint elevation was performed in 23.5% with flexion contracture >15°. No instability was found in cases with joint line elevation. Flexion contracture analysis revealed asymmetry across sides, yet no statistically significant differences. Detailed comparisons show variability in flexion contracture and range of motion, emphasizing the complexity of side-specific outcomes. The study underscores the importance of tailored evaluation and intervention for flexion contracture >15° to optimize postoperative results. Conclusions This study has shown that in patients with varus osteoarthritis of the knee and flexion contracture > 15°, a 2-mm joint line elevation is safe to treat knee flexion contracture and is not associated with mid-flexion laxity. Level of evidence IV Cross sectional study.

References

Harato K, Nagura T, Matsumoto H, Otani T, Toyama Y, Suda Y. Knee flexion contracture will lead to mechanical overload in both limbs: a simulation study using gait analysis. Knee 2008;15(6):467–72.

Campbell TM, Trudel G. Knee flexion contracture associated with a contracture and worse function of the contralateral knee: Data from the osteoarthritis initiative. Arch Phys Med Rehabil 2020;101(4):624–32.

Lombardi Jr AV, Dodds KL, Berend KR, Mallory TH, Adams JB. An Algorithmic Approach to Total Knee Arthroplasty in the Valgus Knee. J Bone Joint Surg 2004;86(suppl_2):62–71.

Minoda Y, Sugama R, Ohta Y, Ueyama H, Takemura S, Nakamura H. Joint line elevation is not associated with mid-flexion laxity in patients with varus osteoarthritis after total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2020;28(10):3226–31.

Martin JW, Whiteside LA. The influence of joint line position on knee stability after condylar knee arthroplasty. Clin Orthop Relat Res 1990;259:146–56.

Mehta N, Burnett RA, Kahlenberg CA, Miller R, Chalmers B, Cross MB. Mid-Flexion Instability After Total Knee Arthroplasty: Diagnosis, Implant Design, and Outcomes. Orthopedics 2023;46(1):e13–9.

Luyckx T, Vandenneucker H, Ing LS, Vereecke E, Ing AV, Victor J. Raising the Joint Line in TKA is Associated With Mid-flexion Laxity: A Study in Cadaver Knees. Clin Orthop Relat Res 2018;476(3):601–11.

Vajapey SP, Pettit RJ, Li M, Chen AF, Spitzer AI, Glassman AH. Risk factors for mid-flexion instability after total knee arthroplasty: a system¬atic review. J Arthroplasty 2020;35(10):3046–54.

Evangelista PJ, Laster SK, Lenz NM, Sheth NP, Schwarzkopf R. A computer model of mid-flex¬ion instability in a balanced total knee arthro¬plasty. J Arthroplasty 2018;33(7S):S265–9.

Hofmann AA, Kurtin SM, Lyons S, Tan¬ner AM, Bolognesi MP. Clinical and radio¬graphic analysis of accurate restoration of the joint line in revision total knee arthro¬plasty. J Arthroplasty 2006;21(8):1154–62.

König C, Matziolis G, Sharenkov A, Taylor WR, Perka C, Duda GN, et al. Collateral ligament length change patterns after joint line elevation may not explain midflexion instability following TKA. Med Eng Phys 2011;33(10):1303–8.

Del Gaizo DJ, Della Valle CJ. Instabil¬ity in primary total knee arthroplasty. Or¬thopedics 2011;34(9):e519–21.

Cross MB, Nam D, Plaskos C, Sheman SL, Lyman S, Pearle AD, et al. Recutting the distal femur to increase maximal knee ex¬tension during TKA causes coronal plane lax¬ity in mid-flexion. Knee 2012;19(6):875–9.

Matziolis G, Brodt S, Windisch C, Roehner E. The reversed gap technique produces anatomical alignment with less midflexion instability in total knee arthroplasty: a pro-spective randomized trial. Knee Surg Sports Traumatol Arthrosc 2016;24(8):2430–35.

Hino K, Ishimaru M, Iseki Y, Watanabe S, Onishi Y, Miura H. Mid-flexion laxity is greater after posterior-stabilised total knee replacement than with cruciate-retaining procedures: a computer navigation study. Bone Joint J 2013;95(4):493–7.

Additional Files

Published

2024-06-30