MUSCULAE DYSTEOPHY. 



135 



away from the acromion, a tendency which is much accentuated 

 when the supraspinatus is also affected. 



The infraspinatus rotates the arm outwards. The muscle being 

 comparatively superficial, alteration in the way of wasting or of 

 hypertrophy is easily recognised. 



Types of Muscular Dystrophy. 



Pectoralis Major 



(lower part) \ 

 Latissimus Dorsi 

 Biceps y. Wasted. 



Supinator Longus ? 

 Intrinsic Muscles I 



of Hand ? 



Pelvis, 

 Thigh, 

 and Leg. 



Glutei \ 



Quadriceps (espe- 

 cially Vastus [-Enlarged. 

 Externus) 



Calf Muscles 



Triceps \ 



Biceps I Wasted 



Brachialis Anticus f early. 

 Supinator Longus ' 



Whole Trapezius 



Pectoralis Major 

 (lower part espe- 

 cially) 



Serratus Magnus \ Also 



Latissimus Dorsi /wasted, 

 (lower part espe- 

 cially) 



Rhomboids 



Sterno-mastoid 



Glutei } 



Flexors of Hip 



Quadriceps and [ Wasted. 



Muscles above i 



Knee J 



Flexors of Hip 

 Flexors of Knee 

 Peronei 



Anterior Tibial 

 Group 



Wasted. 



Flexors of Knee 

 Peronei 



As in Erb's Juvenile 

 Type. 



-Wasted./ 



The triceps extends the elbow. Its long head also adducts the 

 arm. Paralysis of the triceps renders supination of the extended 

 forearm impossible, for the biceps which supinates is also a flexor 

 and will flex the forearm when supination is attempted unless it 

 is antagonised by simultaneous contraction of the triceps. 



The pectoralis major consists of two portions, clavicular and 



