Syndrome of the Quadriga

Biomechanics of the interaction of finger flexor tendons and pulleys in rock climbing

“…The maximally‐contracted muscle bellies of the adjacent unloaded fingers transfer the force to the loaded finger and increase the flexion force of one finger by up to 48 per cent 8. This supports the theory of the quadriga effect described by Verdan 10, where the proximal connections of the muscle bellies of the deep flexor digitorum profundus (FDP) and superficial flexor digitorum superficialis (FDS) finger flexors lead to a cross‐transfer of flexion force from the unloaded to the loaded finger muscle. However, there is no other grip that offers the unique biomechanical properties of the crimp grip 8.…”

Kinematic evaluation of the finger’s interphalangeal joints coupling mechanism—variability, flexion–extension differences, triggers, locking swanneck deformities, anthropometric correlations

“…Avoidance of effects of intertendinous connections: Deep finger flexor intertendinous connections will prevent active deep flexor use when fingers are independently flexed beyond the connections' slack ranges (Verdan, 1960;Leijnse, 1997aLeijnse, , 1997bLeijnse, , 1998. Further finger flexion will then be controlled by the superficial flexor.…”

Reliability of tendon excursion measurements in patients using a color Doppler imaging system

“…1). This immobilization served to prevent limited excursion of the injured FDP caused by connections between flexor tendons (quadriga phenomenon 15 ).…”