Magnetic Resonance Imaging-based Evaluation of Tibial Tuberosity-Trochlear Groove Distance in the North Indian
Shailendra Singh1, Amit Kumar, Vishal Singh
1Department of Orthopaedic Surgery, King George's Medical University, Lucknow, Uttar Pradesh, India.
Introduction:
Patellofemoral instability is a multifactorial condition affecting young and active individuals, with anatomical contributors including trochlear dysplasia, patella alta, and lateralization of the tibial tuberosity. Among the anatomical parameters, the tibial tuberosity-trochlear groove (TT-TG) distance is a key indicator used to evaluate patellofemoral alignment and guide realignment procedures. While normative TT-TG values have been reported in Western populations, data from the Indian population remain limited and inconsistent. This study aims to evaluate the TT-TG distance using magnetic resonance imaging (MRI) in a North Indian cohort and to explore its variations across age, gender, and laterality.
Materials And Methods:
This prospective observational study was conducted at the department of orthopedics over 18 months. A total of 80 patients (66 males and 14 females; aged 18-50 years) with non-pathological knees and no history of surgery or deformity were included. The TT-TG distance was measured using axial MRI scans on a 1.5 Tesla scanner, following established protocols. The measurements were performed independently by a consultant radiologist and an orthopedic surgeon. Statistical analyses included descriptive statistics and unpaired Student's t-tests to assess associations with demographic variables.
Results:
The mean TT-TG distance in the study population was 12.4 ± 2.4 mm. Males had a mean TT-TG distance of 12.09 ± 2.25 mm, whereas females had 13.64 ± 2.52 mm. Although the distance appeared slightly greater in females, the difference was not statistically significant (P = 0.706). Similarly, no significant association was found between TT-TG distance and age group or laterality (right knee vs. left knee). Comparison with prior studies suggests that the TT-TG distance in the Indian population is comparable to Western cohorts but higher than other Asian populations.
Conclusions:
The average TT-TG distance in the North Indian population was found to be 12.4 mm, consistent with global reference values. This study provides foundational normative data that may aid in the clinical assessment and surgical decision-making for patellofemoral instability in Indian patients. Future research with larger sample sizes and clinical correlation is recommended to establish population-specific thresholds for surgical intervention.
