CALCANEO-METATARSAL LIGAMENT— CURB 147 



THE CALCANEO-METATARSAL LIGAMENT— CURB 



The Calcaneo-Metatarsal Ligament. — This is a thick and powerful 

 ligament which unites the calcis to the cuboid and the metatarsal bones. 

 It arises from the back of the tuberosity of the calcis, the commence- 

 ment of the ligament being a little below the summit of the tuber. It 

 then runs straight down the posterior border of the tuber and the outer 

 portion of the posterior aspect of the body of the calcis. Running on 

 to the cuboid, it obtains a powerful insertion into the posterior surface of 

 this bone. It is hence frequently termed the calcaneo-cuboid ligament, 

 particularly in surgical text-books. From the cuboid it is continued on 

 to the head of the external small metatarsal bone, to which the ligament 

 is attached, and where the ligament terminates. Outwardly this ligament 

 is confounded with the outer and more superficial division of the 

 external lateral ligament, whilst inwardly it is confounded with the 

 tarso-metatarsal ligament, and slightly also with its direct continuation — 

 the subtarsal or check ligament of the hind limb. This ligament is 

 coarsely fibrillated, and its fibres run in the longitudinal direction. Its 

 posterior surface is almost perfectly straight from above to below — a point 

 which is of great importance. In the transverse direction this surface is 

 convex. It is in intimate relationship to the fibrous arch which stretches 

 across and completes the tarsal sheath, and to which the name annular 

 ligament is frequently given. 



To appreciate the great importance of this ligament it is necessary 

 to consider the action of the gastrocnemius and flexor metatarsi muscles. 

 When the gastrocnemius muscle acts it becomes the power of a lever, 

 the bar of which extends from the summit of the tuber calcis to the 

 ground, the fulcrum being the lower end of the tibia. The flexor 

 metatarsi during contraction forms the power of a lever of a diff^erent 

 order, since the power in this case acts between the fulcrum, which is 

 again the distal end of the tibia, and the weight, which is represented by 



