Changes in anteroposterior patellar tendon diameter support a continuum of pathological changes.

Area of Science:

• Sports Medicine
• Musculoskeletal Ultrasound
• Tendinopathy Research

Background:

• A proposed continuum of patellar tendon ultrasound changes exists: normal, diffuse, and focal echogenicity.
• The anteroposterior (AP) diameter associated with these pathological states and its changes are not well understood.

Purpose of the Study:

• To investigate the AP diameter across different patellar tendon ultrasound groups (normal, diffuse, focal).
• To examine changes in AP diameter in active volleyball players throughout a season and correlate these with shifts in ultrasound-defined pathology groups.

Main Methods:

• Grey-scale ultrasound was used to assess patellar tendon pathology (normal, diffuse, focal) and AP diameter.
• Measurements were taken from 102 volleyball players at the season's start and 58 players at 6 monthly intervals over 5 months.

Main Results:

• A significant ordinal relationship was found between AP diameter and tendon pathology groups in both men and women (p < 0.05).
• Men's AP diameters: normal (3.4 ± 0.4 mm), diffuse (4.9 ± 0.4 mm), focal (6.5 ± 1.8 mm).
• Women's AP diameters: normal (3.2 ± 0.4 mm), diffuse (4.2 ± 0.4 mm), focal (4.6 ± 0.7 mm).
• Tendons that remained in the same pathological group exhibited less mean change in AP diameter compared to those that transitioned between groups.

Conclusions:

• The findings support the proposed continuum of patellar tendon pathology based on ultrasound echogenicity.
• Mild patellar tendon thickening (AP diameter >4.2 mm in men, >4 mm in women) may indicate subclinical pathology in active athletes.