Central Slip Injury
Central Slip Injury
The central slip is the component of the extensor tendon that inserts into the base of the middle phalanx. Tears occur when there is forced flexion when the finger is fully extended.
The injury results in flexion at the PIPJ and hyperextension of the DIPJ. This is called the Boutonniere deformity.
Mechanism: Forced flexion of an extended finger leads to rupture of the central slip insertion, resulting in the characteristic Boutonniere deformity with PIPJ flexion and DIPJ hyperextension.