The Tibial Tuberosity-Trochlear Groove Distance Can either Increase or Decrease during Adolescent Growth.

Area of Science:

• Orthopedics
• Radiology
• Pediatric Sports Medicine

Background:

• Increased Tibial Tuberosity-Trochlear Groove (TT-TG) distance is a known risk factor for recurrent lateral patella dislocations (RLPD).
• Previous studies indicate a gradual increase in TT-TG distance during growth in healthy individuals.
• Individual changes in TT-TG distance during adolescence in RLPD patients remain understudied.

Purpose of the Study:

• To investigate and quantify the changes in TT-TG distance during skeletal maturity in adolescents with RLPD.
• To determine if TT-TG distance consistently increases or if individual variations occur during the growth spurt in this patient group.

Main Methods:

• Prospective study involving 13 consecutive adolescent patients (mean age 13 years) with open physes and RLPD.
• Magnetic Resonance Imaging (MRI) was used to measure TT-TG distance at baseline and at a three-year follow-up.
• Statistical analysis was performed to assess the change in TT-TG distance over the study period.

Main Results:

• The mean TT-TG distance showed an overall increase of 2.9 mm (95% CI 2.1-3.7) over the three-year follow-up period.
• Individual TT-TG measurements demonstrated variability, with some patients exhibiting an increase and others a decrease in distance.
• These findings indicate that TT-TG distance can change unpredictably during adolescent skeletal maturation in patients with RLPD.

Conclusions:

• The TT-TG distance in patients with RLPD does not uniformly increase during adolescent growth.
• Individualized changes in TT-TG distance, including decreases, can occur during the growth spurt.
• This study challenges the established concept of a consistent TT-TG increase, highlighting the need for individualized assessment in RLPD management.