S^^ A MANUAL OF ANATOMY 



and internal cuneiform is usually continuous in front with the 

 synovial membrane of the middle tarso-metatarsal joint, because the 

 interosseous ligament between these two bones is generally limited 

 to the inferior and anterior portions of the contiguous surfaces. If 

 this ligament should reach the dorsal surface, the naviculo-cuneiform 

 synovial membrane would be entirely isolated from that of the middle 

 tarso-metatarsal joint. 



Arterial Supply. — ^The arterial supply . of the naviculo-cuboid, 

 naviculo-cuneiform, intercuneiform, and cubo- cuneiform joints is 

 derived from the metatarsal branch of the dorsalis pedis and the 

 internal and external plantar arteries. 



Nerve-supply. — ^The dorsalis pedis, internal plantar, and external 

 plantar nerves. 



Movements at the Naviculo-cuneiform, Intercuneiform, and Cubo-cuneiform 

 Joints.— The movements at these joints are very limited, and are of the gliding 

 or to-and-fro variety. They do not affect the position of the foot as regards 

 flexion and extension, or inversion and eversion, but they influence the 

 transverse arch by increasing or diminishing its span. Downward gliding 

 would increase the span, and upward gliding would diminish it. 



The portion of the transverse arch which is formed by the three cuneiform 

 and cuboid bones has the following muscles attached to its various parts — tibialis 

 posticus, flexor brevis hallucis, adductor obliquus hallucis, peroneus longus, 

 flexor brevis minimi digiti, and tibialis anticus. The first four muscles 

 diminish the span, and so deepen the arch, whilst the tibialis anticus increases 

 the span, and so renders the arch wider. 



The Tarso-metatarsal Joints. 



The tarso-metatarsal joints are divided into internal, middle, 

 and external. They all belong to the class diarthrosis, and to the 

 subdivision arthrodia. 



I. Internal Tarso-metatarsal Joint. — ^This is the joint between the 

 internal cuneiform and the first metatarsal bone. The dorsal and 

 plantar ligaments of this joint are so disposed as to meet upon its 

 inner and outer aspects, and thus a complete capsule is formed round 

 the articulation, which capsule is stronger inferiorly and internally 

 than elsewhere. 



The synovial membrane of this joint is peculiar to it. 



II. Middle Tarso-metatarsal Joint. — The bones which enter into 

 this joint are the three cuneiforms and the bases of the second and 

 third metatarsals (sometimes a part of the base of the fourth also). 

 The ligaments are dorsal, plantar, and interosseous. 



The dorsal ligaments. — ^The dorsal surface of the base of the 

 second metatarsal bone receives three dorsal ligaments, one from 

 each cuneiform. The dorsal surface of the base of the third meta- 

 tarsal bone receives a dorsal ligament from the external cunei- 

 form. Moreover, the external cuneiform is connected by a dorsal 

 ligament with the dorsal surface of the base of the fourth metatarsal 

 bone. 



The plantar ligaments are three in number. One passes between 

 the base of the internal cuneiform and the plantar aspects of the 



