6o& A MANUAL OF ANATOMY 



and its superficial position noted. Special attention is to be directed to the 

 middle division of the fascia. On being followed towards the toes, it 

 should be shown to divide into five digital processes, one for each toe. The 

 longitudinal direction of the fibres (from heel to toes) should be observed, but 

 towards the toes superadded transverse fibres are to be displayed. In the 

 interval between the diverging digital processes the plantar digital vessels 

 and nerves are to be sought for and followed along the sides of the toes. The 

 manner in which the digital processes are disposed is to be studied, and the 

 bearing of the middle division of the plantar fascia upon the deformity 

 known as pes cavus is to be carefully noted. In connection with the outer 

 division of the fascia attention should be paid to the strong band which 

 passes between the outer tubercle of the os calcis and the tuberosity on the 

 outer side of the base of the fifth metatarsal bone, and which may be 

 represented by a muscle known as the abductor ossis metatarsi quinti or 

 Wood's muscle. 



The plantar fascia is now to be removed in the following manner : 

 (i) the thin inner division is to be removed in the ordinary way so as to 

 expose the abductor hallucis muscle, which it covers ; (2) the stronger outer 

 division is also to be removed in the usual way so as to expose the abductor 

 minimi digiti, which lies underneath it ; (3) the very strong middle division, 

 which closely covers the flexor brevis digitorum, is to be carefully divided 

 transversely about i inch in front of the heel, the posterior narrow part is to 

 be dissected backwards, and the expanding anterior part is to be reflected for- 

 wards. This dissection will bring into view the flexor brevis digitorum, and it 

 will show the extent to which the superficial fibres of that muscle take origin 

 from the deep surface of the middle division of the fascia. In dissecting the 

 tendon of insertion of the abductor hallucis, the inner head of the flexor brevis 

 hallucis is to be shown joining it, and a branch from the internal plantar nerve 

 is to be looked for entering the abductor hallucis on its deep aspect about the 

 centre. In dissecting the flexor brevis digitorum, it should be shown to end 

 in four tendons for the four outer toes. Each tendon will be found to Ue 

 superficial to a tendon of the long flexor of the toes, and the canal in which 

 each pair of tendons lies before passing along the toes should be studied. 



The sheaths which confine the flexor tendons as they pass along the plantar 

 aspects of the toes are next to be dissected. Upon one or more toes the 

 sheaths are to be laid open, the insertions of the tendons made out, and the 

 vincula accessoria tendinum (ligamenta longa and ligamenta brevia) shown. 

 A similar dissection is to be made in connection with the tendon of the flexor 

 longus hallucis. The intermuscular septum on either side of the short flexor 

 is to be noted, and twigs from the internal plantar nerve are to be looked for 

 entering the muscle on its deep surface. In dissecting the abductor minimi 

 digiti, twigs from the external plantar nerve are to be looked for entering the 

 deep surface of the muscle at its back part. 



The muscles of the first layer are to be divided near their origins and 

 thrown forwards. The tendons of the flexor longus digitorum and flexor 

 longus hallucis are now to be dissected, the former passing forwards and 

 outwards, and the latter forwards and inwards. The crossing between 

 these two tendons should be noted, that of the flexor longus hallucis 

 being uppermost, and the slip which this tendon furnishes to that of 

 the long flexor of the toes should be displayed. The tendon of the flexor 

 longus hallucis is to be followed out to its insertion, and the vincula accessoria 

 tendinum shown within its sheath on the great toe. The flexor or musculus 

 accessorius is to be dissected in connection with the tendon of the long flexor 

 of the toes previous to its division. In dissecting the musculus accessorius 

 the external plantar vessels and nerve are to be carefully preserved as they 

 cross the sole, and twigs of the nerve are to be looked for entering the inferior 

 surface of the muscle at its back part. The four lumbricales muscles are to be 

 dissected in connection with the four tendons of the long tte.xor of the toes. 

 It should be noted tliat the innermost lumbricahs arises only from one tendon, 

 whilst the other three arise each from the contiguous sides of two tendons. 

 A branch from the second digital nerve of the internal plantar should be shown 



