Lateral collateral metatarsophalangeal ligament

The collateral ligaments (or suspensory ligaments ) of the capsuloligamentous complex of the first MTPJ consist of two main collateral ligaments (medial and lateral metatarsosesamoid ligaments(MTSLs)) and two accessory sesamoid ligaments (medial and lateral sesamoid phalangeal ligaments (SPLs)):

• The medial metatarsosesamoid ligament originates from the medial aspect of the metatarsal head to attach to the medial aspect of the proximal phalangeal base. 

• The lateral metatarsosesamoid ligament  originates from the lateral aspect of the metatarsal head to attach to the lateral aspect of the proximal phalangeal base.

• The medial and lateral sesamoidophalangeal ligaments extend from the same proximal attachments with the main collateral ligaments to the periphery of the sesamoid bone.The SPLs are the thickest first MTPJ ligaments and are the main restraints to proximal sesamoid subluxation when high tensile forces are placed across them during hyperextension (dorsiflexion) on walking or running. As a result, the SPLs are also the most commonly injured when hyperextension occurs.