Influence of femoral posterior condylar offset on functional outcomes following posterior-stabilized fixed bearing total knee arthroplasty: a prospective observational study

Jishnu Krishnan K.; Abdul Asraf V.; Saithalikutty Chemmala; Mohamed Shakeeb K. U.

doi:10.18203/issn.2455-4510.IntJResOrthop20262038

Authors

Jishnu Krishnan K. Department of Orthopaedics, MES Medical College, Perinthalmanna, Malappuram, Kerala, India
Abdul Asraf V. Department of Orthopaedics, MES Medical College, Perinthalmanna, Malappuram, Kerala, India
Saithalikutty Chemmala Department of Orthopaedics, MES Medical College, Perinthalmanna, Malappuram, Kerala, India
Mohamed Shakeeb K. U. Department of Orthopaedics, MES Medical College, Perinthalmanna, Malappuram, Kerala, India

DOI:

https://doi.org/10.18203/issn.2455-4510.IntJResOrthop20262038

Keywords:

Knee Society Score, Knee flexion, Osteoarthritis, Posterior condylar offset, Posterior condylar offset ratio, Posterior-stabilised, Total knee arthroplasty

Abstract

Background: Total knee arthroplasty (TKA) provides effective pain relief and functional improvement in advanced osteoarthritis; however, suboptimal postoperative knee flexion persists in some patients. Femoral posterior condylar offset (PCO) is an important determinant of femoral rollback, flexion gap balance and quadriceps efficiency, particularly in posterior-stabilised (PS) TKA. Evidence regarding its influence on functional outcomes remains inconsistent, with limited data from the Indian population.

Methods: A prospective observational study was conducted in 21 patients aged 50–80 years with Kellgren–Lawrence grade 3 or 4 osteoarthritis undergoing posterior-stabilised, fixed-bearing primary TKA between April 2024 and September 2025. Preoperative and postoperative PCO and posterior condylar offset ratio (PCOR) were measured using true lateral radiographs. Functional outcomes were assessed using the Knee Society Score (KSS) at 6 weeks, 3 months and finally at 6 months. Statistical analysis evaluated the association between PCO changes and functional outcomes.

Results: The mean age was 66.81±5.56 years. KSS showed significant improvement over time (p<0.001). Most patients demonstrated minimal changes in PCO (0–2 mm). Patients with preserved or minimally increased PCO had significantly higher Knee Society Scores and better functional outcomes, whereas those with PCO reduction >2 mm had inferior outcomes (p<0.001).

Conclusions: Preservation of femoral PCO is associated with improved functional outcomes following PS TKA. As a modifiable surgical parameter, accurate femoral sizing and posterior condylar resection are essential to optimise postoperative knee function.

References

Carr AJ, Robertsson O, Graves S, Price AJ, Arden NK, Judge A, et al. Knee replacement. Lancet. 2012;379(9823):1331–40.

Kurtz S, Ong K, Lau E, Mowat F, Halpern M. Projections of primary and revision knee arthroplasty in the United States. J Bone Joint Surg Am. 2007;89(4):780–5.

Bourne RB, Chesworth BM, Davis AM, Mahomed NN, Charron KD. Patient satisfaction after total knee arthroplasty: who is satisfied and who is not. Clin Orthop Relat Res. 2010;468(1):57–63.

Mulholland SJ, Wyss UP. Activities of daily living in non-Western cultures: range of motion requirements for hip and knee joint implants. Int J Rehabil Res. 2001;24(3):191–8.

Khemlani K, Chawla A, Nair R, Tripathy SK. Functional outcome of total knee arthroplasty in Indian population: role of high flexion. J Clin Orthop Trauma. 2019;10(1):50–4.

Bellemans J, Banks S, Victor J, Vandenneucker H, Moemans A. Fluoroscopic analysis of the kinematics of deep flexion in total knee arthroplasty. J Bone Joint Surg Br. 2002;84(1):50–3.

Massin P, Gournay A. Optimization of the posterior condylar offset, tibial slope and condylar roll-back in total knee arthroplasty. J Arthroplasty. 2006;21(6):889–96.

Dennis DA, Komistek RD, Mahfouz MR, Haas BD, Stiehl JB. Multicenter determination of in vivo kinematics after total knee arthroplasty. Clin Orthop Relat Res. 2003;(416):37–57.

Bellemans J. Restoring the joint line in total knee arthroplasty: does it matter? Knee. 2004;11(1):3–5.

Goldstein WM, Raab DJ, Gleason TF, Branson JJ, Berland KA. Why posterior condylar offset restoration is important in total knee arthroplasty. Clin Orthop Relat Res. 2006;452:88–93.

Johal P, Hassaballa MA, Eldridge JD, Porteous AJ. The posterior condylar offset ratio. Knee. 2012;19(6):843–5.

Soda Y, Oishi J, Nakasa T, Nishikawa K, Ochi M. Posterior condylar offset ratio and knee flexion after posterior-stabilized total knee arthroplasty. Arch Orthop Trauma Surg. 2007;127(3):167–70.

Arabori M, Matsui N, Kuroda R, Mizuno K, Doita M, Kurosaka M. Posterior condylar offset and flexion in posterior cruciate-retaining and posterior-stabilized TKA. J Orthop Sci. 2008;13(1):46–50.

Bauer T, Biau D, Colmar M, Poux X, Hardy P, Lortat-Jacob A. Influence of posterior condylar offset on knee flexion after total knee arthroplasty. Knee. 2010;17(6):375–80.

Clement ND, MacDonald DJ, Hamilton DF, Burnett R. Posterior condylar offset is an independent predictor of functional outcome after revision total knee arthroplasty. Bone Joint Res. 2017;6(3):172–8.

Zhong Y, Deng Z, Gu C, Li M, Kang Y, Liao W, et al. Optimal variation range of posterior condylar offset and clinical outcomes. Orthop Surg. 2024;16:2708–13.

Chang MJ, Kang SB, Chang CB, Han DH, Park HJ. Posterior condylar offset changes and clinical outcomes in PS TKA. Knee Surg Relat Res. 2020;32(1):10.

Panciera A, Digennaro V, Bulzacki BD, Barile F, Manzetti M, Ferri R, et al. Posterior condylar offset ratio and functional outcome in PS TKA. Eur J Orthop Surg Traumatol. 2023;33(6):2459–64.

Zhong Y, Deng Z, Gu C, Li M, Kang Y, Liao W, et al. The optimal variation range of posterior condylar offset associated with positive clinical outcomes of primary total knee arthroplasty. Orthop Surg. 2024;16:2708–13.

Familiari F. Comparison of posterior condylar offset between anterior and posterior referencing total knee arthroplasty: a meta-analysis of randomised controlled trials. J Clin Med. 2023;12:7453.

Aljuhani W. Measurement of posterior condylar offset and its relationship with knee flexion: an MRI-based study. Med Sci. 2024;3:6758.