Retrospective examination of knee joint anatomy with magnetic resonance images

The knee joint is a complex structure that is exposed to excessive load during daily activities across all age groups. Its morphology has been examined in numerous studies using various imaging methods. However, advancements in surgical techniques and ongoing debates about the suitability of standard implants for different age, gender, and ethnic groups have highlighted the importance of identifying morphometric differences in the bony structures forming the knee joint. This study aimed to investigate whether the morphometric features of these bony structures differ according to age groups and gender. The study is based on the retrospective analysis of knee magnetic resonance imaging records of patients referred to the Department of Radiology at Tokat Gaziosmanpaşa University Hospital for knee MRI between January 2017 and July 2024. Ethical approval was obtained from the Non-Interventional Clinical Research Ethics Committee on 18.01.2024 before the study was conducted. Within the scope of the study, knee magnetic resonance imaging scans of 212 individuals (106 males and 106 females) aged between 18 and 69 years were retrospectively reviewed, and morphometric data were obtained from the images. The data were analyzed by age groups and gender. In our study, morphometric measurements of the femur, tibia, patella, and patellar ligament were compared between genders, and the following values were found in males and females, respectively: medial condyle width: 26.61 ± 1.98 mm and 23.17 ± 1.82 mm, lateral condyle width: 28.92 ± 2.25 mm and 25.01 ± 2.17 mm, bicondylar width: 76.45 ± 4.02 mm and 66.56 ± 3.71 mm, medial condyle height: 61.00 ± 4.27 mm and 54.25 ± 3.26 mm, lateral condyle height: 61.66 ± 4.14 mm and 55.14 ± 3.45 mm, intercondylar fossa width: 20.72 ± 2.14 mm and 18.16 ± 2.47 mm, intercondylar fossa depth: 24.58 ± 2.60 mm and 21.85 ± 2.09 mm, trochlear sulcus depth: 7.79 ± 1.31 mm and 6.81 ± 1.19 mm, trochlear sulcus width: 37.97 ± 2.70 mm and 33.57 ± 2.40 mm, width of the lateral patellar facet: 23.33 ± 2.07 mm and 20.43 ± 1.80 mm, width of the medial patellar facet: 17.07 ± 2.18 mm and 14.56 ± 1.57 mm, tibial width: 77.51 ± 4.27 mm and 68.19 ± 3.40 mm, intercondylar eminence width: 13.11 ± 1.80 mm and 12.10 ± 1.74 mm, depth of the medial tibial condyle: 3.11 ± 0.81 mm and 2.56 ± 0.62 mm, medial tibial plateau depth: 48.80 ± 3.65 mm and 42.47 ± 2.72 mm, lateral tibial plateau depth: 39.22 ± 3.84 mm and 34.21 ± 3.01 mm, patellar length: 44.02 ± 3.17 mm and 38.11 ± 2.69 mm, patellar width: 45.64 ± 3.59 mm and 39.21 ± 2.64 mm, and patellar ligament length: 46.36 ± 5.42 mm and 42.96 ± 4.74 mm. All of these values were found to be significantly higher in males compared to females (p<0.05). In contrast, trochlear angle: 2.93 ± 1.75° and 3.57 ± 2.27°, medial tibial slope: 4.82 ± 1.68° and 5.71 ± 2.17°, and Insall-Salvati Index: 1.05 ± 0.14 and 1.13 ± 0.14 were found to be significantly lower in males than in females (p<0.05). When the measured parameters were compared by age groups, it was found that intercondylar fossa depth, Insall-Salvati Index, and patellar ligament length were significantly higher in the young adult group than in other age groups for both genders, while tibial width was significantly higher in the older adult group in both males and females (p<0.05). No statistically significant difference was observed between the average values of the measured parameters in the right and left knees (p>0.05). Our study revealed that knee anatomy in individuals of Turkish ethnic origin shows significant variation depending on age and gender. A thorough understanding of the morphometric characteristics of the bony structures of the knee is crucial for prosthetic design. Considering that most standard prostheses currently in use have been developed based on anatomical data from Western populations, their appropriateness in terms of age and gender remains debatable. In the current era, where patient-specific arthroplasty is gaining increasing importance, it is believed that anatomical variables such as age, gender, and ethnicity should be taken into consideration in the knee prosthesis design process.