The relationship between the Meary angle and first ray instability
Research type
Research Study
Full title
The relationship between the Meary angle and first ray instability
IRAS ID
360456
Contact name
Chandra Pasapula
Contact email
Sponsor organisation
The Queen Elizabeth Hospital King's Lynn NHS Foundation Trust
Duration of Study in the UK
0 years, 5 months, 31 days
Research summary
First ray instability (FRI) refers to abnormal motion and lack of stability in the first ray of the foot (first metatarsal and medial cuneiform). It is crucial for weight-bearing and push-off during gait. FRI occurs when the first ray moves excessively in the dorsal direction. There are various causes which include: ligamentous laxity (e.g. flatfoot); posterior tibial tendon dysfunction; hallux valgus deformity; pes planus; trauma; iatrogenic.
FRI can cause medial foot pain, a collapsing foot and various deformities such as hallux valgus, pes planus and transfer metatarsalgia. Treatment options range from non- operative including orthotics and tibialis posterior strengthening exercises to operative options such as first tarsometatarsal joint fusion.
To date, there is no study looking at the Meary angle (angle between a line drawn along the longitudinal axes of the talus and the first metatarsal) and first ray instability. The purpose of this study is to see whether there is an association as if so, this would potentially help identify patients at risk of FRI based on their Meary angle.
The main objective of this project is to identify the relationship between first ray instability (how far the first ray can be dorsally translated) and the Meary angle measured on plain film radiographs (x-ray images).
REC name
North East - York Research Ethics Committee
REC reference
25/NE/0195
Date of REC Opinion
9 Oct 2025
REC opinion
Favourable Opinion