Skip to main content
Download PDF

Sexual dimorphism of the posterior condylar offset of the femur and the medial posterior slope of the tibia in non-arthritic knees of Egyptian adults: an MRI study

Journal of Orthopaedic Surgery and Research volume 18, Article number: 353 (2023) Cite this article

Abstract

Background

The aim of this magnetic resonance imaging (MRI) study was to investigate controversial sexual dimorphism of the posterior condylar offset of the femur (the offset) and the posterior slope of the tibia (the slope) in non-arthritic knees of Egyptian adults.

Methods

On 100 male and 100 female MRIs of non-arthritic knees, linear measurements of the distal part of the femur (the offset) and the angular measurements of the proximal part of the tibia (the slope) were performed and compared regarding sex and ethnicity. The intraclass correlation coefficient (ICC) was used to test the interrater agreement.

Results

Both offsets and the lateral offset ratio were larger in males (p < 0.001), the medial offset ratio, and the medial slope in females (p from < 0.001 to 0.007), whereas the lateral slope was sex-free (p = 0.41). Irrespective of sex, however, the medial offset with its ratio, and the medial slope were larger than their counterparts (p < 0.001). Our means of the offsets, their ratios, and the slopes mostly differed from those of other ethnicities (p from ≤ 0.001 to 0.004). ICCs > 0.8 proved MRI’s precision was high.

Conclusion

There was a sexual dimorphism of both the offset and the medial slope in non-arthritic knees of Egyptian adults. We believe future designs of knee implants should consider these differences in order to improve postoperative range of motion and patients’ satisfaction after total knee arthroplasty.

Level of evidence Level III Retrospective Cohort Study.

Trial registration ClinicalTrials.gov identifier: NCT03622034, registered on July 28, 2018.

Background

Bellemans et al. [1] were the first to define the posterior condylar offset of the femur (»the offset«) as the "maximal thickness of the posterior condyle, projected posteriorly to the tangent of the posterior cortex of the femoral shaft" as measured on true lateral radiographs of the knee. Restoration of the offset after total knee arthroplasty (TKA) is important to re-establish normal knee mechanics, maximize range of motion (ROM), and prevent impingement aiming for reduction in knee flexion instability [2, 3].

Several studies exhibited variations in the anthropometric measurements of the knee among different ethnicities [4,5,6,7,8,9,10]. Many have reported a sex difference in knee anthropometrics, forming the basis of the sex specific knee [5, 11,12,13,14]. Ethnic and sex differences were correspondingly noted in the population of the Middle East regarding both arthritic [15] and non-arthritic knees [16]. In a similar fashion, ethnic and sex differences of the offset and the posterior slope of the tibia (»the slope«) were demonstrated by few [9, 17,18,19], whereas others perceived no sex divergence [4].

Some researchers stressed the importance of restoring the offset [1,2,3, 20, 21] and the slope [21,22,23,24,25] in order to reinstate knee flexion after TKA. On the contrary, others found no relation of the offset [26,27,28,29,30,31] and the slope [31] with regard to knee flexion, though anatomical studies found them to be correlated [7, 32].

Hence, given their contribution to knee flexion after TKA and the fact Middle and Far Eastern populations need longer periods of knee flexion owing to religious and social conventions [33], special attention must be paid to restore the normal or nearly normal values of the offset and the slope after TKA.

Our clinical hypothesis was the offset and the slope differed between sexes. Therefore, the aim of this magnetic resonance imaging (MRI) study was to investigate controversial sexual dimorphism of the posterior condylar offset of the femur and the posterior slope of the tibia in non-arthritic knees of Egyptian adults.

Patients and methods

Patients

This was a single-center observational cross-sectional imaging study. Following ethical approval, MRIs of adult patients with suspected knee ligamentous injury in the period between 2017 and 2019 were eligible for inclusion. However, knees with imaging signs of osteoarthritis (albeit grade I), bony or cartilaginous defects, ligamentous injuries as well as those of patients with body mass index (BMI) ≥ 25 were excluded. Of the remaining total, 200 knees were classified as healthy, matched according to age into equal sex groups (100 males, and 100 females) and included in the imaging study.

Methods

Two senior orthopedic surgeons (MAA and MB) performed the measurements. To determine the interrater agreement, the measurements were repeated on 60 randomly chosen images two weeks after the initial ratings.

The imaging technique was published earlier [16]. All MRI measurements were performed on T2-weighted images in the sagittal plane [34].

The posterior condylar offset and the posterior condylar offset ratio of the femur

The reference image was the middle image (Fig. 1B1). On the reference image, we drew the posterior cortical axis of the femur and reproduced it onto the image showing the most posterior projection of the respective femoral condyle on each side. For each femoral condyle, the offset was a vertical distance (in millimeters) connecting the posterior cortical axis of the femur and the most posterior femoral point of the outer margin of the condylar cartilage [34]. For each femoral condyle, the offset ratio was calculated as the fraction of the offset and the longest anteroposterior diameter of the femoral condyle [35] (Fig. 1A1; B1–B3).

Fig. 1
figure 1

Schematic (A) and MRI (B and C) measurement of the posterior condylar offset and the posterior condylar offset ratio of the femur (A1, B1–B3) and the posterior slope of the tibia (A2, C1–C3) on each side of the right knee. AF posterior cortical axis of the femur, AT anatomical axis of the proximal part of the tibia, D longest anteroposterior diameter of the femoral condyle, R ratio of the longest anteroposterior diameter of the femoral condyle and the posterior condylar offset of the femur, O posterior condylar offset of the femur, P tangent of the tibial plateau, S posterior slope of the tibia (slope’s tangent), X most posterior femoral point of the outer margin of the condylar cartilage

Full size image

The posterior slope of the tibia

The reference image was the image showing the insertion of the posterior cruciate ligament (Fig. 1C1). On the reference image, we drew the anatomical axis of the proximal part of the tibia (the line connecting the midpoints of two horizontals 4–5 cm apart) and reproduced its parallel onto the mid-condylar image to which the slope’s tangent was vertical on each side. For each tibial condyle, the slope was an angle (in degrees) between the tangent of the tibial plateau, and either the slope’s tangent to the most of the superior bone profile on the lateral or the slope’s tangent to the upper portion of the anterior and posterior bone profile on the medial side [36] (Fig. 1A2; C1–C3).

Statistical analysis

We used G Power (v. 3.1.9.7.; Franz Faul, Kiel University, Germany) to calculate statistical power a priori, and SPSS™ (v. 12.0.; IBM Corporation, Somers, NY USA) to test the difference between averaged measurements using parametric (one sample mean test, and independent samples t-test), and nonparametric (Mann–Whitney-U test) statistical tests.

To find a medium effect size (d = 0.50) with 90% statistical power at p < 0.05, 86 knees per group for independent samples t-test, 90 for Mann–Whitney U test, and 44 total for one sample mean test were required.

In testing the interrater agreement, we interpreted the intraclass correlation coefficient (ICC) as acceptable (> 0.5), moderate (> 0.6), good (> 0.7), high (> 0.8), and excellent (> 0.9) [37].

Results

The average age was 34.2 ± 11.2 years (range 18–60) with no difference between males (32.1 ± 11 years) and females (36.2 ± 11.1 years) (p = 0.65).

Both offsets and the lateral offset ratio were larger in males (p < 0.001), the medial offset ratio, and the medial slope in females (p from < 0.001 to 0.007), whereas the lateral slope was sex-free (p = 0.41) (Table 1). Irrespective of sex, however, the medial offset with its ratio and the medial slope were larger than their counterparts (p < 0.001) (Table 2).

Table 1 Posterior condylar offset and the posterior condylar offset ratio of the femur, as well as the posterior slope of the tibia on each side with regard to sex
Full size table
Table 2 Posterior condylar offset and the posterior condylar offset ratio of the femur, as well as the posterior slope of the tibia with regard to side
Full size table

The comparison of the offset, the offset ratios, and the slope from various studies is shown in Tables 3 and 4. Where applicable, means of both offsets and their ratios differed between ours and various studies (p from < 0.001 to 0.004), slopes included (p from ≤ 0.001 to 0.003) except for the medial slope in the study by Zhang et al. [38] (p = 0.51).

Table 3 Values of the posterior condylar offset and the posterior condylar offset ratio of the femur in the literature
Full size table
Table 4 Values of the posterior slope of the tibia in the literature
Full size table

ICCs were high throughout (> 0.8) (Table 5).

Table 5 Inter-rater agreement of the MRI measurements
Full size table

Discussion

The most important finding of this MRI study was the sexual dimorphism of the posterior condylar offset of the femur and the medial posterior slope of the tibia in non-arthritic knees of Egyptian adults. To the best of our knowledge, no prior studies have measured the two on the Middle Eastern cohort. The current research is, in fact, a continuation of previously published work on the MRI-based anthropometric measurement of the Egyptian non-arthritic knees [16].

Irrespective of sex, the medial offset was larger than its counterpart, a finding supported by multitude of studies [8, 18, 32, 39]. Contemporary TKA designs, however, do not address the issue [21]. Even though some custom implants have managed to do so, a long-term follow-up seems necessary [43, 44]. Addressing this polarity may ensure proper anteroposterior placement of the femoral component which could help avoid notching as well as internal rotation of the femoral component, especially if posterior reference instruments are used.

Sexual dimorphism of the offset was formerly reported by many authors. Koh et al. [18] have shown sex difference of the offset and its ratio with both offsets larger in males and both ratios larger in females which is somewhat in line with male supremacy of our lateral offset ratio. These results, along with other studies disclosing sex differences of the offset and its ratio [7, 19, 32, 34, 45], uphold the necessity of sex-specific femoral component design in reestablishing the offset for males and females in Asian and Middle Eastern populations. Still, various authors [8, 39, 46] presented no sex discrepancy vis-à-vis the offset and its ratio. Numerous studies have found no significant difference between sex-specific and standard knee implants regarding clinical and radiological outcomes, patients’ satisfaction and complication rate [31, 47, 48].

Some may argue a sex-specific femoral component might not be essential as the offset may be recreated using a posterior referencing system to perform a measured resection of the posterior condyles of the femur that will preserve any difference between them [18]. Nevertheless, without the utilization of a sex-specific femoral component at a given anteroposterior diameter of the femoral component in use, the offset’s sex-split of only 2–3 mm will either cause overcutting of the posterior offset on one hand or overstuffing with smaller or larger implanted femoral components on the other.

The importance an offset restoration bears on postoperative range of flexion appears controversial and depends on the type of knee replacement. Some researchers advocate the postoperative decrease in the offset by more than 3 mm reduces the postoperative ROM in Cruciate–Retaining (CR) yet not in Posterior–Stabilized (PS) knee implants. It is, therefore, critical to preserve the offset in the CR rather than in PS knees to ensure optimal ROM after surgery [20]. Wang et al. [49] found the offset restoration plays a major role in the optimization of active knee flexion during weight-bearing conditions after PS TKA, with no benefit to non-weight-bearing knee flexion or any other clinical outcome [49]. On the flip side, Ishii et al. [29] found no correlation of individual differences of the offset with current CR or PS prostheses and changes in knee flexion after 1-year follow-up [29]. Chang et al. [27] reported no difference in postoperative offset in Anterior-Referenced (AR) and Posterior-Referenced (PR) group. Moreover, the offset was more consistently preserved after surgery in the PR group. The postoperative offset and ratio changes did not affect the postoperative ROM. Similar clinical outcomes were obtained in the AR as well as PR groups [27].

Weinberg et al. [8] were the first to report Caucasians have greater offsets than African Americans [8]. Wang et al. [19] measured the offset and its ratio in Chinese patients corroborating the former was significantly smaller in both sexes than that of the Western population, as reported by Johal et al. [35]. Conversely, the offset ratio was significantly larger than that of the Western population indicating not only the size of the distal part of the femur differed from the Western population but also its shape. This would imply a Chinese knee having a greater offset at a given anteroposterior diameter of the distal part of the femur. Likewise, Koh et al. observed a smaller offset of the Korean population as opposed to Western population in both sexes, though the former had a larger offset ratio [18, 35]. Therefore, considering the variance of the offsets among different ethnicities, a knee implant design under the axiom of “one-size-fits-all” would inevitably over- or under-restore the offset if used in diverse ethnic groups [8].

On top of that, both slopes were significantly larger in Egyptians as opposed to Caucasians [41] (Table 4). In juxtaposition with Asians, however, the results were variable [42]. The slopes were smaller in the Egyptian population as opposed to Asian population according to Ho et al. [40]. The medial was larger and the lateral slope smaller in Egyptian population than in Asian population as per Haddad et al. [41]. The medial slope was not significantly different, yet lateral was smaller in Egyptian population than its Asian counterpart as reported by Zhang et al. [10, 38].

The restoration of the slope has been shown to delay the tibiofemoral impingement and thus substantially improve the range of knee flexion [50]. It is crucial a prosthetic slope approximates the native as ligaments have been accustomed to the latter [51]. Currently, the optimal slope for the prosthetic knee remains debatable, despite the fact a 0–7 cut is routinely recommended [51, 52]. Following this recommendation, based mostly on the Western populations’ slope, an Egyptian patient may obtain a slope smaller than that prior to arthroplasty, resulting in a tight knee flexion due to magnified tension of the posterior cruciate ligament (if retained), as well as the collaterals [23, 25, 53]. Limited flexion would cause difficulty with regard to activities such as kneeling and squatting, quite frequent in an Egyptian milieu [33, 54].

Our study has certain limitations. The cohort was a single ethnic group which makes the sexual dimorphism of the offset and the slope limited to our geographic area although it may provide a background for comparison with other similar studies elsewhere. We feel more ethnicity-based research is indispensable to begin with. In addition, the measurements were performed on MRIs of non-arthritic knees. This is not a usual stance while performing TKA on arthritic knees. We nonetheless think measurements on healthy knees should act as the foundation in designing new implants for specific populations. Knowing what healthy looks like is, in a nutshell, a mandatory first step to knowledge. Surgeons should, therefore, consider the issue of extra bony cuts in cases of severe deformity during the preoperative planning. Lastly, the absence of a musculoskeletal radiologist among the coauthors might be perceived as a justly limitation. Comparing our results with those formerly reported in other studies might be criticized for being unreliable due to differences in measurement methods, types of imaging, and diverse conditions of the knee joints. Our intent here, however, was not to perform a meta-analysis, but rather to corroborate our review of the current literature with a relatively meaningful statistical calculus. Our study does merit some advantages, of course, such as a large cohort measured by two raters on the MRI as well as favorable statistical power (≥ 90%). The MRI has demonstrated superb capabilities in measuring the offset as it can appraise the thickness of the articular cartilage of merely ≈ 2.75 mm [55], even 2.15 mm [56] according to some reports [57]. Radiographic measurement underestimates the offset due to positioning of the knee and transparency of articular cartilage, hence possibly instilling debate on its importance in TKA [39]. MRI consequently provides a more precise anatomical measurement as the bedrock of prospective knee implant design.

Conclusion

There was a sexual dimorphism of the posterior condylar offset of the femur and the medial posterior slope of the tibia in non-arthritic knees of Egyptian adults. This would indicate most of the commonly used knee implants, even those sex specific, may not provide a perfect fit unless sex and ethnic variations in both the offset and the slope were previously assessed. We believe future designs of knee implants should consider these differences in order to improve postoperative ROM and patients’ satisfaction after TKA.

Availability of data and materials

The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

Abbreviations

AR:

Anterior referenced

BMI:

Body mass index

CR:

Cruciate retaining

CT:

Computed tomography

ICC:

Intraclass correlation coefficient

MRI:

Magnetic resonance imaging

PR:

Posterior referenced

PS:

Posterior stabilized

ROM:

Range of motion

TKA:

Total knee arthroplasty

References

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

    Article  CAS  Google Scholar 

  2. Kang KT, Koh YG, Son J, Kwon OR, Lee JS, Kwon SK. A computational simulation study to determine the biomechanical influence of posterior condylar offset and tibial slope in cruciate retaining total knee arthroplasty. Bone Jt Res. 2018;7:69–78.

    Article  Google Scholar 

  3. Onodera T, Majima T, Nishiike O, Kasahara Y, Takahashi D. Posterior femoral condylar offset after total knee replacement in the risk of knee flexion contracture. J Arthroplast. 2013;28:1112–6.

    Article  Google Scholar 

  4. Bisicchia S, Scordo GM, Prins J, Tudisco C. Do ethnicity and gender influence posterior tibial slope? J Orthop Traumatol. 2017;18:319–24.

    Article  PubMed  PubMed Central  Google Scholar 

  5. Li P, Tsai TY, Li JS, Zhang Y, Kwon YM, Rubash HE, et al. Morphological measurement of the knee: race and sex effects. Acta Orthop Belg. 2014;80:260–8.

    PubMed  Google Scholar 

  6. Mensch JS, Amstutz H. Knee morphology as a guide to knee replacement. Clin Orthop Relat Res. 1975;112:231–41.

    Google Scholar 

  7. Weinberg DS, Gebhart JJ, Wera GD. An anatomic investigation into the relationship between posterior condylar offset and posterior tibial slope of one thousand one hundred thirty-eight cadaveric knees. J Arthroplast. 2017;32(1659–1664): e1651.

    Google Scholar 

  8. Weinberg DS, Streit JJ, Gebhart JJ, Williamson DF, Goldberg VM. Important differences exist in posterior condylar offsets in an osteological collection of 1058 femurs. J Arthroplast. 2015;30:1434–8.

    Article  Google Scholar 

  9. Weinberg DS, Williamson DFK, Gebhart JJ, Knapik DM, Voos JE. Differences in medial and lateral posterior tibial slope: an osteological review of 1090 tibiae comparing age, sex, and race. Am J Sports Med. 2016;45:106–13.

    Article  PubMed  Google Scholar 

  10. Yue B, Varadarajan KM, Ai S, Tang T, Rubash HE, Li G. Differences of knee anthropometry between Chinese and white men and women. J Arthroplast. 2011;26:124–30.

    Article  Google Scholar 

  11. Chaichankul C, Tanavalee A, Itiravivong P. Anthropometric measurements of knee joints in Thai population: correlation to the sizing of current knee prostheses. Knee. 2011;18:5–10.

    Article  PubMed  Google Scholar 

  12. Cheng FB, Ji XF, Lai Y, Feng JC, Zheng WX, Sun YF, et al. Three dimensional morphometry of the knee to design the total knee arthroplasty for Chinese population. Knee. 2009;16:341–7.

    Article  PubMed  Google Scholar 

  13. Kwak DS, Surendran S, Pengatteeri YH, Park SE, Choi KN, Gopinathan P, et al. Morphometry of the proximal tibia to design the tibial component of total knee arthroplasty for the Korean population. Knee. 2007;14:295–300.

    Article  PubMed  Google Scholar 

  14. Uehara K, Kadoya Y, Kobayashi A, Ohashi H, Yamano Y. Anthropometry of the proximal tibia to design a total knee prosthesis for the Japanese population. J Arthroplasty. 2002;17:1028–32.

    Article  CAS  PubMed  Google Scholar 

  15. Hafez MA, Sheikhedrees SM, Saweeres ES. Anthropometry of Arabian arthritic knees: comparison to other ethnic groups and implant dimensions. J Arthroplast. 2016;31:1109–16.

    Article  Google Scholar 

  16. Abdelnasser MK, Khalifa AA, Bassem M, Abdelhameed MA, Adam MF, Bakr HM, et al. Anthropometric measurements of non-arthritic knees in an Egyptian population: an MRI-based study. J Orthop Surg Res. 2021;16:552.

    Article  PubMed  PubMed Central  Google Scholar 

  17. Endo Y, Takemura M, Monma M, Mutsuzaki H, Mizukami M. Difference in sex and the effect of a dominant lower extremity in the posterior tibial slope angle in healthy Japanese subjects. Asia-Pacific J Sports Med Arthrosc Rehabil Technol. 2021;23:8–12.

    Google Scholar 

  18. Koh YG, Nam JH, Chung HS, Kim HJ, Chun HJ, Kang KT. Gender differences in morphology exist in posterior condylar offsets of the knee in Korean population. Knee Surg Sports Traumatol Arthrosc. 2019;27:1628–34.

    Article  PubMed  Google Scholar 

  19. Wang W, Tsai TY, Yue B, Kwon YM, Li G. Posterior femoral condylar offsets of a Chinese population. Knee. 2014;21:553–6.

    Article  PubMed  Google Scholar 

  20. Goutham GDV, Jain VK, Sinha S, Arya RK. Effect of posterior condylar offset in post operative range of motion in cruciate retaining and sacrificing TKR: a comparative analysis. J Orthop. 2020;20:342–6.

    Article  PubMed  PubMed Central  Google Scholar 

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

    Article  Google Scholar 

  22. Fujimoto E, Sasashige Y, Masuda Y, Hisatome T, Eguchi A, Masuda T, et al. Significant effect of the posterior tibial slope and medial/lateral ligament balance on knee flexion in total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2013;21:2704–12.

    Article  PubMed  Google Scholar 

  23. In Y, Kim JM, Woo YK, Choi NY, Sohn JM, Koh HS. Factors affecting flexion gap tightness in cruciate-retaining total knee arthroplasty. J Arthroplast. 2009;24:317–21.

    Article  Google Scholar 

  24. Shi X, Shen B, Kang P, Yang J, Zhou Z, Pei F. The effect of posterior tibial slope on knee flexion in posterior-stabilized total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2013;21:2696–703.

    Article  PubMed  Google Scholar 

  25. Singh G, Tan JH, Sng BY, Awiszus F, Lohmann CH, Nathan SS. Restoring the anatomical tibial slope and limb axis may maximise post-operative flexion in posterior-stabilised total knee replacements. Bone Jt J. 2013;95-b:1354–8.

    Article  CAS  Google Scholar 

  26. Bauer T, Biau D, Colmar M, Poux X, Hardy P, Lortat-Jacob A. Influence of posterior condylar offset on knee flexion after cruciate-sacrificing mobile-bearing total knee replacement: a prospective analysis of 410 consecutive cases. Knee. 2010;17:375–80.

    Article  CAS  PubMed  Google Scholar 

  27. Chang MJ, Kang S-B, Chang CB, Han DH, Park HJ, Hwang K, et al. Posterior condylar offset changes and its effect on clinical outcomes after posterior-substituting, fixed-bearing total knee arthroplasty: anterior versus posterior referencing. Knee Surg Relat Res. 2020;32:10.

    Article  PubMed  PubMed Central  Google Scholar 

  28. Degen RM, Matz J, Teeter MG, Lanting BA, Howard JL, McCalden RW. Does posterior condylar offset affect clinical results following total knee arthroplasty? J Knee Surg. 2018;31:754–60.

    Article  PubMed  Google Scholar 

  29. Ishii Y, Noguchi H, Takeda M, Sato J, Toyabe S. Posterior condylar offset does not correlate with knee flexion after TKA. Clin Orthop Relat Res. 2013;471:2995–3001.

    Article  PubMed  PubMed Central  Google Scholar 

  30. Kim JH. Effect of posterior femoral condylar offset and posterior tibial slope on maximal flexion angle of the knee in posterior cruciate ligament sacrificing total knee arthroplasty. Knee Surg Relat Res. 2013;25:54–9.

    Article  PubMed  PubMed Central  Google Scholar 

  31. Song SJ, Bae DK, Kim KI, Jeong HY. Changes in femoral posterior condylar offset, tibial posterior slope angle, and joint line height after cruciate-retaining total knee arthroplasty. Knee Surg Relat Res. 2016;28:27–33.

    Article  PubMed  PubMed Central  Google Scholar 

  32. Cinotti G, Sessa P, Ripani F, Postacchini R, Masciangelo R, Giannicola G. Correlation between posterior offset of femoral condyles and sagittal slope of the tibial plateau. J Anat. 2012;221:452–8.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  33. 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;24:191–8.

    Article  CAS  PubMed  Google Scholar 

  34. Wernecke GC, Seeto BG, Chen DB, MacDessi SJ. Posterior condylar cartilage thickness and posterior condylar offset of the femur: a magnetic resonance imaging study. J Orthop Surg (Hong Kong). 2016;24:12–5.

    Article  CAS  PubMed  Google Scholar 

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

    Article  PubMed  Google Scholar 

  36. Hashemi J, Chandrashekar N, Gill B, Beynnon BD, Slauterbeck JR, Schutt RC Jr, et al. The geometry of the tibial plateau and its influence on the biomechanics of the tibiofemoral joint. J Bone Jt Surg Am. 2008;90:2724–34.

    Article  Google Scholar 

  37. Koo TK, Li MY. A guideline of selecting and reporting intraclass correlation coefficients for reliability research. J Chiropr Med. 2016;15:155–63.

    Article  PubMed  PubMed Central  Google Scholar 

  38. Zhang Y, Wang J, Xiao J, Zhao L, Li ZH, Yan G, et al. Measurement and comparison of tibial posterior slope angle in different methods based on three-dimensional reconstruction. Knee. 2014;21:694–8.

    Article  PubMed  Google Scholar 

  39. Voleti PB, Stephenson JW, Lotke PA, Lee GC. Plain radiographs underestimate the asymmetry of the posterior condylar offset of the knee compared with MRI. Clin Orthop Relat Res. 2014;472:155–61.

    Article  PubMed  Google Scholar 

  40. Ho JPY, Merican AM, Hashim MS, Abbas AA, Chan CK, Mohamad JA. Three-dimensional computed tomography analysis of the posterior tibial slope in 100 knees. J Arthroplast. 2017;32:3176–83.

    Article  Google Scholar 

  41. Haddad BZ, Konan S, Mannan K, Scott G. Evaluation of the posterior tibial slope on MR images in different population groups using the tibial proximal anatomical axis. Acta Orthop Belg. 2012;78(6):757–63.

    PubMed  Google Scholar 

  42. Khattak MJ, Umer M, Davis ET, Habib M, Ahmed M. Lower-limb alignment and posterior tibial slope in Pakistanis: a radiographic study. J Orthop Surg (Hong Kong). 2010;18:22–5.

    Article  PubMed  Google Scholar 

  43. Bali K, Walker P, Bruce W. Custom-fit total knee arthroplasty: our initial experience in 32 knees. J Arthroplasty. 2012;27:1149–54.

    Article  PubMed  Google Scholar 

  44. Ng VY, Arnott L, Li J, Hopkins R, Lewis J, Sutphen S, et al. Comparison of custom to standard TKA instrumentation with computed tomography. Knee Surg Sports Traumatol Arthrosc. 2014;22:1833–42.

    Article  PubMed  Google Scholar 

  45. Han H, Oh S, Chang CB, Kang SB. Anthropometric difference of the knee on MRI according to gender and age groups. Surg Radiol Anat. 2016;38:203–11.

    Article  PubMed  Google Scholar 

  46. Voleti PB, Stephenson JW, Lotke PA, Lee GC. No sex differences exist in posterior condylar offsets of the knee. Clin Orthop Relat Res. 2015;473:1425–31.

    Article  PubMed  Google Scholar 

  47. Bourne R. A gender-specific prosthesis was similar to a standard prosthesis in women having total knee replacement. J Bone Jt Surg Am. 2011;93:396.

    Article  Google Scholar 

  48. Kim YH, Choi Y, Kim JS. Comparison of standard and gender-specific posterior-cruciate-retaining high-flexion total knee replacements: a prospective, randomised study. J Bone Jt Surg Br. 2010;92:639–45.

    Article  Google Scholar 

  49. Wang JT, Zhang Y, Liu Q, He Q, Zhang DL, Zhang Y, et al. Effect of posterior condylar offset on clinical results after posterior-stabilized total knee arthroplasty. Chin J Traumatol. 2015;18:259–66.

    Article  PubMed  Google Scholar 

  50. Kawamura H, Bourne RB. Factors affecting range of flexion after total knee arthroplasty. J Orthop Sci. 2001;6:248–52.

    Article  CAS  PubMed  Google Scholar 

  51. Gromov K, Korchi M, Thomsen MG, Husted H, Troelsen A. What is the optimal alignment of the tibial and femoral components in knee arthroplasty? Acta Orthop. 2014;85:480–7.

    Article  PubMed  PubMed Central  Google Scholar 

  52. Lustig S, Scholes CJ, Stegeman TJ, Oussedik S, Coolican MRJ, Parker DA. Sagittal placement of the femoral component in total knee arthroplasty predicts knee flexion contracture at one-year follow-up. Int Orthop. 2012;36:1835–9.

    Article  PubMed  PubMed Central  Google Scholar 

  53. Jojima H, Whiteside LA, Ogata K. Effect of tibial slope or posterior cruciate ligament release on knee kinematics. Clin Orthop Relat Res. 2004. https://doi.org/10.1097/01.blo.0000138960.57680.60194-198.

    Article  PubMed  Google Scholar 

  54. Kurosaka M, Yoshiya S, Mizuno K, Yamamoto T. Maximizing flexion after total knee arthroplasty: the need and the pitfalls. J Arthroplast. 2002;17:59–62.

    Article  Google Scholar 

  55. Connolly A, FitzPatrick D, Moulton J, Lee J, Lerner A. Tibiofemoral cartilage thickness distribution and its correlation with anthropometric variables. Proc Inst Mech Eng H. 2008;222:29–39.

    Article  CAS  PubMed  Google Scholar 

  56. Cohen ZA, McCarthy DM, Kwak SD, Legrand P, Fogarasi F, Ciaccio EJ, et al. Knee cartilage topography, thickness, and contact areas from MRI: in-vitro calibration and in-vivo measurements. Osteoarthr Cartil. 1999;7:95–109.

    Article  CAS  Google Scholar 

  57. Tashiro Y, Uemura M, Matsuda S, Okazaki K, Kawahara S, Hashizume M, et al. Articular cartilage of the posterior condyle can affect rotational alignment in total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc. 2012;20:1463–9.

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

We would like to thank the radiology department staff in our hospital on following the MRI protocol and for their assistance with the collection of images.

Funding

Open access funding provided by The Science, Technology & Innovation Funding Authority (STDF) in cooperation with The Egyptian Knowledge Bank (EKB). This research did not receive any specific Grant from funding agencies in the public, commercial, or not-for-profit sectors.

Author information

Authors and Affiliations

  1. Orthopedic and Traumatology Department, Assiut University Hospital, Assiut, Egypt

    Mohammad Kamal Abdelnasser, Mohammed Anter Abdelhameed, Micheal Bassem, Mahmoud Faisal Adam, Hatem M. Bakr & Yaser E. Khalifa

Authors
  1. Mohammad Kamal Abdelnasser
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Mohammed Anter Abdelhameed
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Micheal Bassem
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Mahmoud Faisal Adam
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Hatem M. Bakr
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Yaser E. Khalifa
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

YK and MKA carried out the study conception and design and performed the surgeries. MB, MAA, and MFA carried out data acquisition and measurements. MKA, MAA, and HMB carried out analysis and interpretation of data, drafted the manuscript, and designed the figures and tables. YK and MKA did the critical revision. All authors discussed the results and commented on the manuscript. All authors read and approved the final manuscript. Both the first and the second authors contributed equally to the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Mohammed Anter Abdelhameed.

Ethics declarations

Ethics approval and consent to participate

The ethical committee of our institution approved the study (IRB No.: 17100554), Faculty of Medicine, Assiut University, Egypt (Telephone, Fax: + 20882332278, email: ethicscommittee12@yahoo.com, http://afm.edu.eg). ClinicalTrials.gov identifier: NCT03622034.

Consent for publication

Consent to participate was obtained from all patients to use their radiographs for this research. This article does not contain any experimental studies with human participants or animals performed by any of the authors.

Competing interests

All authors declare no competing interests.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Abdelnasser, M.K., Abdelhameed, M.A., Bassem, M. et al. Sexual dimorphism of the posterior condylar offset of the femur and the medial posterior slope of the tibia in non-arthritic knees of Egyptian adults: an MRI study. J Orthop Surg Res 18, 353 (2023). https://doi.org/10.1186/s13018-023-03833-2

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s13018-023-03833-2

Keywords

Journal of Orthopaedic Surgery and Research

ISSN: 1749-799X