- Email: [email protected]
Bilateral agenesis of extensor carpi ulnaris
Bilateral Agenesis of Extensor Carpi Ulnaris--H. Gloobe and S. Liberty
B I L A T E R A L A G E N E S I S OF E X T E N S O R C A R P I U L N A R I S
H. G L O O B E and S. L I B E R T Y , Tel Aviv Agenesis of one of the superficial extensor muscles in the forearm is very rare (Hollinshead, 1969). Current textbooks of anatomy do not mention the absence of extensor carpi ulnaris, and to the best of our knowledge this has not been reported in publications during the last twenty years. The authors feel that this case report may be of interest to anatomists and orthopaedic surgeons. During the routine dissection of 150 upper limbs performed in the Department of Anatomy, Tel Aviv University Medical School, the bilateral absence of this muscle was observed in only one cadaver, a male aged eighty-three years, of European origin. On dissection of the wrists, due to the agenesis of the extensor carpi ulnaris, the postero-medial aspect of the distal end of the ulna was free and lacked soft tissue (Fig. 1). DISCUSSION
Absence of several muscles in the body has been mentioned in publications and textbooks. Seib (1934) reported upon the bilateral agenesis of the psoas minor among 2,627 cadavers in 54.5%. Some racial differences were found to exist, the muscle apparently being most often absent in Negroes and least often in yellow races. Agenesis of the pyramidalis has been reported (Beaton and Anson, 1939) in 20.3% of whites and 12.5% of Negroes; they stated also that the absence was more common bilaterally than on one side only. Daseler and Anson (1943) reported that the plantaris longus was absent in 6.6% of 750 lower extremities.
Fig. 1 Left wrist joint, dorsal aspect. Agenesis of the extensor carpi ulnaris exposed the distal part of the ulna. The H a n d - - V o l . 5
No. 2
1973
t75
Bilateral Agenesis o/ Extensor Carpi UInaris--H. Gloobe and S. Liberty
C o n c e r n i n g the f o r e a r m , several i n v e s t i g a t o r s s t a t e d the following: A d a c h i (1909) r e p o r t s an a b s e n c e of the p a l m a r i s longus in 3.4% of a r m s a m o n g the J a p a n e s e , while N a k a n o (1923) finds an i n c i d e n c e of agenesis in t h e Chinese of only 2.2%. R e i m a n n a n d his c o - w o r k e r s (1944) state t h a t the m o s t c o m m o n variation of t h e p a l m a r i s longus is its absence, w h i c h m a y be e i t h e r u n i - or b i l a t e r a l ; t h e y f o u n d it a b s e n t in 12.8% of t h e i r 1,600 cases. T h u s it is e v i d e n t t h a t agenesis is m u c h m o r e c o m m o n in the O c c i d e n t a l t h a n in the O r i e n t a l races. T h o m p s o n , M c B a t t s a n d D a n f o r t h (1921) studied t h e genetics of t h e p a l m a r i s longus in several r a c i a l g r o u p s a n d a p p a r e n t l y d e m o n s t r a t e d t h a t the a b s e n c e of t h e muscle is a M e n d e l i a n c h a r a c t e r i s t i c . D w i g h t (1887) r e p o r t e d a missing flexor c a r p i radialis in o n e case. L a c k of o n e of t h e superficial e x t e n s o r muscles is v e r y r a r e ( H o l l i n s h e a d , 1969). C o n c e r n i n g the deep e x t e n s o r s of t h e f o r e a r m ( P a r s o n a n d R o b i n s o n , 1898) r e p o r t e d a b s e n c e of the e x t e n s o r pollicis brevis in eight out of 126 limbs (6.3%), a n d of t h e e x t e n s o r pollicis longus in two o u t of 131 limbs (1.5%). C a u l d w e l l (1943) f o u n d no i n c i d e n c e o f a b s e n c e of t h e e x t e n s o r indicis, a l t h o u g h in 3% of the series the t e n d o n was m a r k e d l y r e d u c e d in size. This r e p o r t adds a f u r t h e r agenesis, t h a t of a superficial e x t e n s o r of the wrist, to those d e s c r i b e d earlier. This m a y be of g r e a t i m p o r t a n c e to t h e h a n d s u r g e o n dealing with t e n d o n t r a n s f e r in cases of u l n a r o r m e d i a n n e r v e p a l s y (White, 1960; P h a l e n a n d Miller, 1947). SUMMARY
A n e x t r e m e l y r a r e v a r i a t i o n of b i l a t e r a l agenesis of the e x t e n s o r c a r p i ulnaris is described. This m a y be of g r e a t i m p o r t a n c e to t h e o r t h o p a e d i c surgeon d e a l i n g with t e n d o n transfer. REFERENCES
ADACHI, B. (1909) Beitfiige zur Anatomic der Japaner. Die Statistik der muskelvariet~iten. Zeitschrift ftir Morphologie und Anthropologie, 12: 261-312. BEATON, L. F. and ANSON, B. J. (1939) Pyramidalis Muscle: its occurrence and size in American Whites and Negroes. American Journal of Physical Anthropology 25: 261-269. CAULDWELL, E. W., ANSON, B. J. and WRIGHT, R. R. (1943) The Extensor 'Indicis Proprius Muscle; A Study of 263 Consecutive Specimens. Quarterly Bulletin of Northwestern University Medical School, 17: 267-271. DASELER, E. H. and ANSON, B. J. (1943) The Plantaris Muscle; an Anatomical Study of 750 specimens. Journal of Bone and Joint Surgery, 25: 822-827. DWIGHT, T. (1887) Notes on muscular abnormalities. Journal of Anatomy and Physiology 22: 96-102. HOLLINSHEAD, W. H. (1969) Variations and abnormalities of the superficial extensor muscles. In Anatomy for Surgeons, Vol. 3. The Back and Limbs 2nd Edition, New York, Hoeber Medical Division, Harper and Row, 428-429. NAKANO, T. (t922-1923) Beitr~tge zur Anatomic der Chinesen. Die Statistik der muskelvariet~iten. Folia Anatomica Japonica 1: 273-282. PARSONS, F. G. and ROBINSON, A. (1899) Eighth report of the committee of collective investigation of the Anatomical Society of Great Britain and Northern Ireland for the year 1897-1898, Journal of Anatomy and Physiology 33: 189-203. PHALEN, G. S. and MILLER, R. C. (1947) The Transfer of Wrist Extensor Muscles to Restore or Reinforce Flexion Power of the Fingers and Opposition of the Thumb. Journal of Bone and Joint Surgery, 29: 993-997. REIMANN, A. F., DASELER, E. H., ANSON, B. J. and BEATON, L. E. (1944) The Palmaris Longus Muscle and Tendon. A study of 1600 Extremities. Anatomical Record, 89: 495-505. THOMPSON, ,J. W., McBATTS, J. and DANFORTH, C. H. (1921) Hereditary and racial variation in the musculus palmaris longus. American Journal of Physical Anthropology 4: 205-218. SEIB, G. A. (1934) Incidence of the m. psoas minor in man. American Journal of Physical Anthropology 19: 229-246. WHITE, W. L. (1960) Restoration of Function and Balance of the Wrist and Hand by Tendon Transfers. Surgical Clinics of North America. 40: 427-459. 176
The H a n d - - V o l . 5
No. 2
1973
B I L A T E R A L A G E N E S I S OF E X T E N S O R C A R P I U L N A R I S
H. G L O O B E and S. L I B E R T Y , Tel Aviv Agenesis of one of the superficial extensor muscles in the forearm is very rare (Hollinshead, 1969). Current textbooks of anatomy do not mention the absence of extensor carpi ulnaris, and to the best of our knowledge this has not been reported in publications during the last twenty years. The authors feel that this case report may be of interest to anatomists and orthopaedic surgeons. During the routine dissection of 150 upper limbs performed in the Department of Anatomy, Tel Aviv University Medical School, the bilateral absence of this muscle was observed in only one cadaver, a male aged eighty-three years, of European origin. On dissection of the wrists, due to the agenesis of the extensor carpi ulnaris, the postero-medial aspect of the distal end of the ulna was free and lacked soft tissue (Fig. 1). DISCUSSION
Absence of several muscles in the body has been mentioned in publications and textbooks. Seib (1934) reported upon the bilateral agenesis of the psoas minor among 2,627 cadavers in 54.5%. Some racial differences were found to exist, the muscle apparently being most often absent in Negroes and least often in yellow races. Agenesis of the pyramidalis has been reported (Beaton and Anson, 1939) in 20.3% of whites and 12.5% of Negroes; they stated also that the absence was more common bilaterally than on one side only. Daseler and Anson (1943) reported that the plantaris longus was absent in 6.6% of 750 lower extremities.
Fig. 1 Left wrist joint, dorsal aspect. Agenesis of the extensor carpi ulnaris exposed the distal part of the ulna. The H a n d - - V o l . 5
No. 2
1973
t75
Bilateral Agenesis o/ Extensor Carpi UInaris--H. Gloobe and S. Liberty
C o n c e r n i n g the f o r e a r m , several i n v e s t i g a t o r s s t a t e d the following: A d a c h i (1909) r e p o r t s an a b s e n c e of the p a l m a r i s longus in 3.4% of a r m s a m o n g the J a p a n e s e , while N a k a n o (1923) finds an i n c i d e n c e of agenesis in t h e Chinese of only 2.2%. R e i m a n n a n d his c o - w o r k e r s (1944) state t h a t the m o s t c o m m o n variation of t h e p a l m a r i s longus is its absence, w h i c h m a y be e i t h e r u n i - or b i l a t e r a l ; t h e y f o u n d it a b s e n t in 12.8% of t h e i r 1,600 cases. T h u s it is e v i d e n t t h a t agenesis is m u c h m o r e c o m m o n in the O c c i d e n t a l t h a n in the O r i e n t a l races. T h o m p s o n , M c B a t t s a n d D a n f o r t h (1921) studied t h e genetics of t h e p a l m a r i s longus in several r a c i a l g r o u p s a n d a p p a r e n t l y d e m o n s t r a t e d t h a t the a b s e n c e of t h e muscle is a M e n d e l i a n c h a r a c t e r i s t i c . D w i g h t (1887) r e p o r t e d a missing flexor c a r p i radialis in o n e case. L a c k of o n e of t h e superficial e x t e n s o r muscles is v e r y r a r e ( H o l l i n s h e a d , 1969). C o n c e r n i n g the deep e x t e n s o r s of t h e f o r e a r m ( P a r s o n a n d R o b i n s o n , 1898) r e p o r t e d a b s e n c e of the e x t e n s o r pollicis brevis in eight out of 126 limbs (6.3%), a n d of t h e e x t e n s o r pollicis longus in two o u t of 131 limbs (1.5%). C a u l d w e l l (1943) f o u n d no i n c i d e n c e o f a b s e n c e of t h e e x t e n s o r indicis, a l t h o u g h in 3% of the series the t e n d o n was m a r k e d l y r e d u c e d in size. This r e p o r t adds a f u r t h e r agenesis, t h a t of a superficial e x t e n s o r of the wrist, to those d e s c r i b e d earlier. This m a y be of g r e a t i m p o r t a n c e to t h e h a n d s u r g e o n dealing with t e n d o n t r a n s f e r in cases of u l n a r o r m e d i a n n e r v e p a l s y (White, 1960; P h a l e n a n d Miller, 1947). SUMMARY
A n e x t r e m e l y r a r e v a r i a t i o n of b i l a t e r a l agenesis of the e x t e n s o r c a r p i ulnaris is described. This m a y be of g r e a t i m p o r t a n c e to t h e o r t h o p a e d i c surgeon d e a l i n g with t e n d o n transfer. REFERENCES
ADACHI, B. (1909) Beitfiige zur Anatomic der Japaner. Die Statistik der muskelvariet~iten. Zeitschrift ftir Morphologie und Anthropologie, 12: 261-312. BEATON, L. F. and ANSON, B. J. (1939) Pyramidalis Muscle: its occurrence and size in American Whites and Negroes. American Journal of Physical Anthropology 25: 261-269. CAULDWELL, E. W., ANSON, B. J. and WRIGHT, R. R. (1943) The Extensor 'Indicis Proprius Muscle; A Study of 263 Consecutive Specimens. Quarterly Bulletin of Northwestern University Medical School, 17: 267-271. DASELER, E. H. and ANSON, B. J. (1943) The Plantaris Muscle; an Anatomical Study of 750 specimens. Journal of Bone and Joint Surgery, 25: 822-827. DWIGHT, T. (1887) Notes on muscular abnormalities. Journal of Anatomy and Physiology 22: 96-102. HOLLINSHEAD, W. H. (1969) Variations and abnormalities of the superficial extensor muscles. In Anatomy for Surgeons, Vol. 3. The Back and Limbs 2nd Edition, New York, Hoeber Medical Division, Harper and Row, 428-429. NAKANO, T. (t922-1923) Beitr~tge zur Anatomic der Chinesen. Die Statistik der muskelvariet~iten. Folia Anatomica Japonica 1: 273-282. PARSONS, F. G. and ROBINSON, A. (1899) Eighth report of the committee of collective investigation of the Anatomical Society of Great Britain and Northern Ireland for the year 1897-1898, Journal of Anatomy and Physiology 33: 189-203. PHALEN, G. S. and MILLER, R. C. (1947) The Transfer of Wrist Extensor Muscles to Restore or Reinforce Flexion Power of the Fingers and Opposition of the Thumb. Journal of Bone and Joint Surgery, 29: 993-997. REIMANN, A. F., DASELER, E. H., ANSON, B. J. and BEATON, L. E. (1944) The Palmaris Longus Muscle and Tendon. A study of 1600 Extremities. Anatomical Record, 89: 495-505. THOMPSON, ,J. W., McBATTS, J. and DANFORTH, C. H. (1921) Hereditary and racial variation in the musculus palmaris longus. American Journal of Physical Anthropology 4: 205-218. SEIB, G. A. (1934) Incidence of the m. psoas minor in man. American Journal of Physical Anthropology 19: 229-246. WHITE, W. L. (1960) Restoration of Function and Balance of the Wrist and Hand by Tendon Transfers. Surgical Clinics of North America. 40: 427-459. 176
The H a n d - - V o l . 5
No. 2
1973