FOURTH EDITION

AIDS TO THEEXAMINATION, ,

OF THE PERIPHERALNERVOUS SYSTEM

Iw. B. SAUNDERS IOn hc:half of the l,U.JrJ,nlOn of Brain

FOURTH EDITION

AIDS TO THEEXAMINATIONOF THE PERIPHERALNERVOUS SYSTEM

~ W.B. SAUNDERS

EDINBURGH • LONDON • NEWYORK • PHILADELPHIA • ST LOUIS • SYDNEY • TORONTO 2000

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Some of the material in thi s work is © Crown copyright 1976. Reprintedby permission of the Co ntro ller of Her Majesty's Stationery Office.

First published 2000

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I

PREFACE

In 1940 Dr George Riddoch was Consultant Neurologist to the Army. He realised thenecessity of providing centres to deal with peripheral nerve injuries during the war. Incollaboration with Professor J. R. Learrnonth, Professor of Surgery at the University ofEdinburgh, peripheral nerve injury centres were established at Gogarburn nearEdinburgh and at Killearn near Glasgow. Professor Learmonth wished to have anillustrated guide on peripheral nerve injuries for the use of surgeons working in generalhospitals. In collaboration with Dr Ritchie Russell, a few photographs demonstrating thetesting of individual muscles were taken in 1941. Dr Ritchie Russell returned to Oxford in1942 and was replaced by Dr M. J. McArdle as Neurologist to Scottish Command. Thephotographs were completed by Dr McArdle at Gogarburn with the help of theDepartment of Medical Illustration at the University of Edinburgh. About twenty copies inloose-leaf form were circulated to surgeons in Scotland.

In 1943 Professor Learmonth and Dr Riddoch added the diagrams illustrating theinnervation of muscles by various peripheral nerves modified from Pitres and Testut,(Les Neufs en Schemas, Doin, Paris, 1925) and also the diagrams of cutaneous sensorydistributions and dermatomes. This work was published by the Medical ResearchCouncil in 1943 as Aids to the Investigation of Peripheral Nerve Injuries (War MemorandumNo.7). It became a standard work and over the next thirty years many thousands ofcopies were printed.

It was thoroughly revised between 1972 and 1975 with new photographs and many newdiagrams and was republished under the title Aids to the Examination of the PeripheralNervous System (Memorandum No. 45), reflecting the wide use made of this booklet bystudents and practitioners and its more extensive use in clinical neurology, which wasrather different from the war time emphasis on nerve injuries.

In 1984 the Medical Research Council transferred responsibility for this publication tothe Guarantors of Brain for whom a new edition was prepared. Modifications were made tosome of the diagrams and a new diagram of the lumbosacral plexus was included.

Most of the photographs for the 1943, 1975 and 1986 editions show Dr McArdle, whodied in 1989, as the examining physician. A new set of colour photographs has beenprepared for this edition, the diagrams of the brachial plexus and lumbosacral plexus havebeen retained, but all the other diagrams have been redrawn.

ACKNOWLEDGEMENIS

The Guarantors of Brainare very grateful to:

Patricia Archer PhD for the drawings of the brachial plexus;amld~JIlIkMm;Ralph Hutchings for the photography

Paul Richardson for the artwork and diagrams

Michael Hutchinson MB BDS for advice on the neum-anatomy

Sarah Keer-Keer (Harcourt Publishers) for her help and~1t..

CONTENTS

Introduction 1

Spinal accessory nerve 3

Brachial plexus 4

Musculocutaneous nerve 12

Axillary nerve 14

Radial nerve 16

Median nerve 24

Ulnar nerve 30

Lumbosacral plexus 37

Nerves of the lower limb 38

Dermatomes 56

Nerves and root supply of muscles 60

Commonly tested movements 62

INTRODUCTION

This at las is intended as a guide to the exami nation of pat ients with lesion s of periph eralnerves and nerve roots.

These examinations sho uld, if possible , be co nducte d in a qu iet room where pat ien tand examiner will be free fro m distraction . For both motor and sen sory testing it isimportant th at the patient sho uld first be warm. The nature and object of th e tests shouldbe explained to th e patient so tha t his interes t and co-op erat ion are sec ure d. If e ithershows signs of fatig ue, t he session sho uld be discont inued a nd resum ed late r.

Motor testing

Amuscle may act as a prime mover, as a fixator, as an antagonist, or as a synergist. Thus, flexorcarpi ulna ris acts as a prime mover when it flexes and ad du c ts the wrist; as a fixator when itimmobilises the pisiform bone du ring contraction of th e adductor digit i minimi; as anantagonist when it resist s extens ion of th e wrist; and as a synergist when th e digits, but notthe wrists, are extended.

As far as possible the acti on o f each muscle sho uld be obse rved sepa rate ly and a notemade of th ose in whic h power has be en re tai ned as well as of th ose th a t are wea k o rparalysed. It is usual to examine th e power of a muscle in relatio n to th e movement of asingle joint. It has lon g been customary to use a 0 to 5 sca le for recording muscle power,but it is gene rally recogn ised th at subd ivisio n of grade 4 may be helpful.

o No contraction1 Flicker or t race of cont raction2 Active movement, with gravity eliminate d3 Active movement against gravity4 Active movement against gravity and resistan ce5 Normal power

Grades 4-, 4 and 4+, may be used to indicat e movement aga ins t slight. mod erate an dstrong resistan ce respec t ively.

The models employed in this work were not chosen becau se th ey showed unusualmuscular developm en t; th e ease with whic h the co nt rac tio n of muscles is ide nt ified varieswith the build of the pat ien t, and it is essent ial th at th e examiner sho uld both look for an dendeavour to feel the contraction of an accessible mu scle and/or th e movement of itstendon. In most of the illustrations the opti mum point for palpation has been marked.

Muscles have been arranged in the order of th e origin of th eir mot or supply from nervetrunks, which is co nvenient in many exam inations. Usually only one met hod of test ingeach muscle is shown but, whe re necessa ry, mult iple illust rat ion s have been include d if amuscle has more than one impo rta nt act ion. The examiner sho uld apply th e tes ts as theyare illustrated, becau se th e techniques show n will eliminate many of the trap s for theinexperienced provided by 't rick' movemen ts. It sho uld be noted that each of th e method sused tests, as a ru le, the acti on of muscles at a single joint.

When testing a movement, th e limb should be firmly supporte d proximal to the relevantjoint, so that th e test is confined to the chosen muscle group and do es not require th epatient to fix the limb proximally by mu scle co nt ract ion. In this book, thi s principle is

SPINAL ACCESSORY NERVE

Fig. 1 Trapezius (Spinal accessory nerve and 0 , ( 4)

The pat ient is elevati ng the shoulder against resistan ce.Arrow: t he thick upper part of t he mu scle can be seen and felt .

Fig.2 Trapezius (Spinal accessory nerve and O . ( 4)

The pat ient is pushing the palms of the hands hard against a wall with the elbows fu llyextended. Arrow: th e lower f ibres of t rapezius can be seen and felt .

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BRACHIAL PLEXUS 5

fig.4 The approximate area within which sensory changes may be found in complet elesions of the brachia l plexus «(5. (6, (7. C8, T1).

Hg.5 The appr oximate area within which sensory changes may be fou nd in lesions of theupper roots «( 5.(6) of the brachial plexus.

6 BRACHIAL PLEXUS

Fig.6 The approximate area wi thin which sensory changes may be found in lesionsof th elower roo ts (C8. T1) of the brachial plexus.

BRACHIAL PLEXUS 7

Fig.7 Rhomboid s (Dorsal scapul ar nerve; ( 4, (5)

The patient is pressing the palm of his hand backwards against th e examiner's hand.Arrow: the muscle bel lies can be felt and some times seen.

Fig.8 Serratus a nterior (long thoracic ne rve; (5, e6, 0 )

The patient is pushing against a wall. The left se rratus ante rior is pa ralysed and there iswinging of the scapula.

8 IlRACHIAL PLEXUS

Fig. 9 Pecto ralis Majo r: Clavicular Head {lateral pectora l nerve; ( S, (6)

The upper a rm is above th e ho rizonta l and the patien t is pushing forward agai nst theexaminer's hand. Arrow: t he clavicular head of pectoralis major can be seen and fel t .

Fig. 10 Pectoralis Majo r: Ste rnocostal Head (latera l and medial pectoral ne rves; (6, ( 7,C8)

The patie nt is adduct ing the upper arm ag ainst resistan ce .Arrow: the sterno-costal head can be seen and fe lt.

BRACHIAL PLEXUS 9

f ig. 11 Supraspinat us (Sup rascapular nerve; (S, ( 6)

The patient is abduct ing the upper arm aga inst resist ance.Arrow: t he muscle belly can be felt and somet imes seen.

Fig. 12 Inf raspinatus (Suprascapular nerve; (5. ( 6)

The patient is ext ernall y rotating the up per arm at t he sho ulder against resistance. Theexamine r's right hand is resist ing t he movement and sup port ing t he forearm wit h t heelbow at a right angle; h is left hand is supporti ng the elbow and preventing abduction o fthe arm. A rrow: the muscle bell y can be seen and felt .

10 BRACHIAL PLEXUS

..

Fig.13 lat issimu s Dorsi (Thoracod orsal ne rve; ( 6, C7, C8)

The upper arm is hor izontal and the pat ient is addueting it against resista nce. Lowerarrow : the muscle belly can be seen and felt. The upper arrow points to teres major.

Fig . 14 latissimus Dorsi (Thoracod orsal ne rve; (6, C7, C8)

The Muscle bell ies can be f elt to cont ract w hen the patient coughs.

HKACl IIA L PLEXUS 11

Fig.1 5 Teres Major (Subscapular nerve; (S, (6, 0)

The patient is adducting the elevated upper arm against resistance.Arrow: the muscle belty can be seen and felt .

MUSCULOCUTANEOUS NERVE

Coracobrachi alis----1111MUSCULOCUTANEOUSNERVE - - - - - + 1

Brachialis

lateral cutaneous nerve \altha forearm --II

Fig. 16 Diagram of t he musculocut aneous nerve, its majo r cutaneous branch and t hemuscles which it supplies.

MUSCULOTANEQUS NERVE 13

Fig. 17 The approximate area within w hich sensory changes may be found in lesions ofthe musculocutaneous nerve. (The distribution of t he lat eral cutaneous nerve of t heforearm.)

Fig.1 8 Biceps (Musculocutaneous nerve; (S. (6)

The pat ient is flexing the supinated forearm against res istance.Arrow: t he muscle belly can be seen and felt .

AX ILLARY NERVE

AXILlARY NERVE ------)~~~~~r;;::::==::::

UPPER CUTANEOUSNERVE OF THE ARM - - ----......., \J'-- - -i-- - - - RADIAL NERVE

~_o-+------- Teres minor

Fig _19 Diagram of the axillary nerve, its major cutaneous branch and the muscles wh ichit suppnes.

o

f ig_20 The approximate area w ithin which sensory changes may be fou nd in lesions ofthe axillary nerve.

AXILLARY NERVE 15

Fig. 21 Deltoid (Ax illary nerve; {S. ( 6)

The pat ient is abducting the upper arm against resistance.Arrow: the anterior and middle f ibres of t he muscle can be seen and f elt .

Fig.22 Deltoi d (Axillary nerve; { 5, (6)

The patient is ret ract ing the abducted upper arm ag ainst resistance.Arrow: the posterior fibres of deltoid can be seen and felt .

RA DIAL NERVE

AX IUARY NERVE -----:.,-- 7'''':

Triceps . long head - - - - - -1Triceps . lateral head

------- Triceps, medtal head

1--1- - - - - - - - RADIAL NERVE

Brachiol'adaall$ --------1

Extensor carpi radaalis longus ----Il-'l

Exten sor carpi radialiSbrevis

Supinator

Extensor carpi utnans ------Il.....Extensor digllorum -------r;:- ,Extensor digiti mlnl mi -----£:iAbductor polliCis longus ~

Extensor polllClS Ioogus ------\l""Extensor polliCiS brevis -----;;,..­

Extensor indios

POSTERIOR INTEROSS EOUSNERVE (deep branch)

SUPERFICIAL RADIAL NERVE

Fig.23 Diagram of t he radial nerve, it s major cutaneous branch and the muscles which itsuppli es.

RADIAL NERVE 17

Fig.24 The app roximate area within which sensory changes may be found in high les ionsof the radi al nerve (above th e origi n of t he posterior cutaneou s nerves of th e arm andforearm). The average area is usually considerably smaller. and absence of sensory changeshas been recorded .

Fig.2S The approximate area within which sensory cha nges may be found in lesions ofthe radial nerve above the elbow joint and below the origi n of the posterior cutaneo usnerve of the forearm. (The distr ib ut ion of the superficial t erminal branch of th e rad ialnerve.) Usual area sha ded, with dark blue line; light blue lines show small and large area s.

18 KAlJIAL NEKVE

Fig.26 Triceps (Radia l nerve; cs. C7, (8)

The patient is extending the forea rm at the elbow against res istance .Arro ws: the long and la te ra l heads of the muscle (a n be seen and felt .

Fig. 27 Ext ensor Carpi Radialis l ongus (Radia l nerve; (5. ( 6)

The patient is extending an d abdu ct ing th e ha nd at the wrist against resistance.Arrows: t he muscle belly and tendon (a n be fe lt and usually see n.

RADIAL NERVE 19

A

•

/

Fig_28 Brachiorad ial is (Radial nerve; (5, (6)

The pat ient is flexing the forea rm against resistance with the forearm midway betweenpronation and supination. Arrow: the muscle belly (an be seen and felt .

20 RADIAL NERVE

Fig.29 Supinat or {Rad ial nerve ; ( 6. 0)

The patient is supinating the forearm aga inst restst ence with the forearm extended at theelbow.

RADIAL N ERVE 21

Fig. 30 Extensor Carp i Ulnar is {Poste r ior interosseous nerve; (7, ( 8)

The pat ien t is extendi ng and adducti ng the hand a t t he wrist against resist ance .Arrows: th e muscle belly and the tendon (an be see n and felt .

Fig. 31 Ext ensor Digitoru m (Post eri or interosseous nerve; (7, C81

The patient' s han d is firmly supported by the exa miner's right ha nd. Extension at themetacarpopha langea l joints is ma intained against the res ist ance of the fingers of t heexemtner's left ha nd. A rro w: t he muscle belly can be see n an d felt .

22 RADIAL NERVE

Fig. 32 Abductor Pollicis Longus (Posterior inte rosseou s nerve; O . (8)

The pa t ient is ab ducting the thumb at the carpo -metece rpet joint in a plan e at rightangles to the palm . Arrow: the tendon can be seen and felt an te rior and close ly adjacentto t he tendon of extensor pctncrs brevis (d . Fig . 34).

Fig.33 Extensor Pollicis l ongus (Posterior interosseous nerve; 0 , (8)

The pat ient is extend ing the thumb at the interphalangeal joint against resistance.Arrow: the tendon can be seen and felt .

RADIAL NERVE 23

Fig_34 Extensor Poll id s Brevis (Posterior int erosseous nerve; C7. C8)

The patient is extending the thu mb at the metacarpophalangea l joint aga inst resistance.Arrow: the tendon can be seen and felt (d . Fig. 32).

MEDIAN NERVE

1-- - - - - - - - - - MEDIAN NERVE

Sensory

)

Flexor poIhcis longus

IlLI

h '-- - ANTERIOR INTEROSS EOU S NERVE

'd 't-- Flexor retinaculum

~Irt\

1\+ - - Palmar branch --I--~

Firstlumbrical ------!'-J---'!ll!

Pronator quadratus ------+_

Motor

Abductor pomos breVI"'-===E~~~Flexor pollicis brevis _

Opponens poll icis --- - tV

Pronal or teres -------1Flexor carpi radialis - - - - - -tr;Palman s longus -------1Flexor d1gitorum superliciahs

Second lumbr ica l --'

Fig.35 Diagr am of t he median nerve. its cutaneous branches an d the muscles which itsupplies . Note: th e white rectangle signifies that the muscle indicat ed receives a part af itsnerve supply f rom another per ipheral nerve (d. Figs. 45. 57 and 58).

MEDIAN NERVE 25

A

•

Fig.36 The app rox imate areas within which sensory changes may be found in lesion s ofthe median nerve in: A t he fo rearm. B the carpal tunnel.

26 MEDIAN NERVE

Fig_37 Pronator Teres (Median nerve; ( 6, 0 )

The patien t is pro nat ing th e forearm aga inst resistance.Arr ow: th e muscle belly can be fe lt and somet ime seen .

Fig. 38 Flexor Carpi Radial is (Median nerve; ( 6 , 0 )

The pat ien t is f lexing and abd uct ing t he hand at t he w rist aga inst resist ance.Arrow : the tendon (an be seen and felt .

MEDIAN NERVE 27

Fig_39 flexor Digi to rum Superf icialis (Median nerve ; C7, C8, Tt)

The pati ent is f lexing the f inger at th e proximal int erphalageal joint against resistancewith the proximal phalanx fixed. This test does not el iminate th e possibility of f lexion atthe proximal inte rphalangeal jo in t being prod uced by flexor digit orum profundus.

Fig.4O Flexor Digitoru m Profundus I and II (Anterior interosseous nerve; ( 7, (8)

The patien t is flexing the distal phalanx of the index finger agai nst resistance with themiddle phalanx fixed.

28 MEDIAN NERVE

Fig_41 Flexor Pol lid s l ongu s (Anterior interosseous nerve; 0. C8)

The patient is fle xing the distal phalanx of the thumb aga inst resist ance while theproximal phalanx is f ixed.

Fig_42 Abductor Pollicis Brevis (Medi an nerve; C8, 11)

The pat ient is abducting the thumb at fight ang les to the palm aga inst resista nce .Arrow: t he muscle can be seen and fe lt.

M£lJIAN NERVE 29

/

Fig.43 Opponens Pollicis (Median nerve; ca, T1)

The pat ien t is touching the base of the little finger wit h the thu mb against reslstence.

Fig. 44 lst lumb rical-Interosseous Muscle (Median and ulnar nerves; C8, 11)

The pati ent is extendi ng the f inge r at t he proximal inte rphalangeal joint aga instresistance wit h the metacar po phalangeal joint hyperextended a nd fixed.

ULNAR NERVE

I

I

----- ULN AR NERVE

Sensory

IDorsal cutaneousbranch

Palmar cutaneous ,branch

Deep motor branch

Superficial terminalbranches

--- MEDIAL CUTANEOUSNERVE OF THE ARM

--- - Flexor carpi ulnaris

I 11-- - - - Flexor digilorumprofundus III & IV

11-- - - MEDIAL CUTANEOUSNERVE OFTHE

FOREARM

Four th lumb rical

~~== ~~:nl~~s } digiti minimi~ Flexor

i~Thi rd lumbrical ----------1'<'

Motor

Adductor ponies - - - - - - - - - - -0<.Flexor pollicis brevis -,<;,,~

t st Palmar interosseous -----/

1st Dorsal interosseous

Fig.4S Diag ram of t he ulnar nerve, it s cutaneous bra nches and the mu scles which itsupplies.

ULNAR NERVE 31

A

B

c

Fig_46 The approximate areas within which sensory changes may be found in lesions ofthe ulnar nerve : A above the origin of the dorsal cutaneous bran ch, Bbelow the origin ofthe dorsal cutaneous branch and above the origin of the pa lmar branch, C below theorigin of the palmar branch.

32 ULNAR NERVE

Fig.47 The approximate area w it hi n w hich sensory changes may be found in lesions ofthe medial cutaneous nerve of the forearm.

Fig.48 Flexor Carpi Ulnaris (Ulnar nerve; a .C8. Tt )

The patient is abducti ng the little finger against resistance. The tendon of uexcr car piulnar is can be seen and felt (ar ro w) as the muscle comes into act ion to f ix the pisiformbone from which abd uctor d igiti min im i ar ises. If flexor carpi utnens is in t act, the tendon isseen even w hen abductor dig it i minimi is paral ysed (see also Fig. 49).

ULNAR NERVE 33

Fig.49 Flexor Carpi Ulnaris (Ulnar nerve; 0 , C8, T1)

The patient is flex ing and adducting the hand at the wrist against resistance.Arrow:the tendon can be seen and felt .

Fig. SO Flexor Digitorum Prof un dus III and IV (Ulnar nerve; 0 , C8)

The patient is flex ing the distal interphalangeal joint against resistance while the middlephalanx is fixed.

34 ULNAR NERVE

Fig . 51 Abductor Digit i M inim i (Ulnar nerve; C8, 11)

The patient is abducting the litt le finge r against resistance.Arrow: t he muscle belly can be fe lt and seen.

Fig .52 Flexor Dig it i M in im i (Ulnar nerve; C8, 11)

The patient is flexing t he litt le f inger at the metacarpophalangeal joint aga inst resistancewith the finge r extended at both interpha langeal jo ints.

ULNAR NERVE 3S

Fig_53 r trst Dorsal Interosseous Muscle (Ulnar nerve; C8, 11)The patient is abducting the index finger aga inst resistance.Arrow. the muscle belly can be felt and usually seen.

Fig. S4 Second Palmar Interosseous Muscle (Ulnar nerve; C8, T1)

The pat ient is adduct ing the index finger against resistance.

36 ULNAR NERVE

Fig. 55 Adductor Polltcls (Ulnar nerve; C8. T1)

The patient is adducting the thumb at right angles to th e palm against the resistan ce oft he exam iner's f inger.

LUMBOSACRAL PLEXUS

Perineal ne rve

Dor sa l nerve ofpenis or c li loris

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I~~~:::;;;~:-;Ne rve 10

levator a ni ande xte rna l s phl m::le,

branches to

______ Obtura to r e l le rn us

~ Adductor longu s

iJ~--1,~:'----: Adductor brevi S

Adductor magnus

/ ----- Grac ili s

/ - - - - Cuta ne ous

I\~"-~-{\\:~~""'- OBTUA"'TOR NERVE

Rectu s temcr ta-----J.VI SluS l . teralis - - - - - \-J

Yulus in l erme dius ----\, - >.------T---\\tit\-~k_---=--_1----:p~o~.~..~rior c utan.ousV. SluS me d ia li s ne,v. 01 t hig h

Medl.I ----=:::::=:'I;::=~

To lUaeus------~,

SCIATIC NERVE - - _ ,

Psoas muscle

Supe rio r and

interior gluteal

Ner ve 10s.rto rius mu s cle

Cutaneous nerv es

ot Ih igh

Ge nito le mo ra l nerve~

Ner ves 10 quadriceps

f EMO RAL NER ve <,

Iliohypog as tric l'Ierv. - - -"

Ili o inguina l ner ve - - _,

SCIATIC NERVE

I-HI-- - - - - - - - - - - - Common peron ealI+l-- - - - - - - - - - - - - Tiblal

Saphenous nerve -----:--\,-- \li t "\-'

Fig.56 Diagram of the lumbosacral plexus, its branches and the muscles which they supp ly.

NERVES OF THE LOWER LIMB

Adductor magnus

Cutaneous branch

\c-~I~t::===-;;;;;;I Adductor brevisMEDIAL CUTANEOUS

NERVe QFTHE THIGH1t-!lI-- - - - - - Adductor longus

Iliacus

{

Rectus femoris

Quadriceps vas tcs l.ateraIiS.semens vastcs Intermedius --/Y'L" .I I ' . - - - - - - - - - Gracilis

vastcs medi alis 1\,INTERMEOIATE CUTANEOUSNERVe OF TH E THI GH ------;

LATERAL CUTANEOUSNERVE OFTHETHIGH ----1 \

FEMORAL NERVE - - - - - + ---1:-1..... "•• ""'=,---__... OBTU RATOR NERVE

( //

COMMON PERONEAL NERVE 'I,

SUPERFICIAL PERONEAL NERVE - ­Peroneus longus

Deep PERONEAL NERVE

)-Ii}+ - - - - - - - - Tibial is anterior

Peroneus brevis ---------Extensor digilofum longus

LATERAL CUTANEOUSNERVE OF THE CALF ------/ 11

Peroneus terlius - - - - - - - - -

-t- - - - - Extensor hallucis longus

SAPHENOUS NERVE

Fig. 57 Diagram of the nerves on the anterior aspect of t he lower l imb, their cutaneousbranches and the muscles which t hey supply.

NERVES OF THE LOWER LIMB 39

)f- - - - - - - - - Biceps, long head

)l- - - - - - - - - Biceps. short head

I f\-''f-- - - - POSTERIOR CUTANEOUSNERVE OF THE THIGH

f '. \"-,"',f-- - - - - - - - Gluteus maximus

1~~~r=========-( G , uteuS med iUS[' Gluteus minimus

____~--'~L'\t_---'--',-- INFER IOR GLUTEAL NERVE

Semim embranosus -------11-'

Semitendinosus

SCIATIC NERVE

Adductor ma gnus -------j

Pir iformis

SUPERIOR GLUTEAL NERVE -~--';~(<,,!-~ _Tensor fasciae latae

,

)COMMON PERON EAL NERVE

Gastrocnemius. medial head -~~\

Soleus ,I'i!-- - - - - - Gas trocnemius, lateral head

Tibialis posterior

Flexor digilorum long us ------It'l -;t-------- Flexor hallucis longus

TIBIALNERVE --------1SURAL NERVE

CALCA NEAL BRANC H ------1 'i-'l-- - -, LATERAL PLANTAR NERVE to :MEDI AL PLANTAR NERVE to' ----"''\ Abduc tor digiti minimiAbd uctor nauccs Flexor digiti mini miFlexor digitorum brevis Adducto r hallucisFlexor hallucis brevis InterosseiCutaneous branches Cutaneous branches

Fig. 58 Diagram of the ne rves on the posterior aspect of the lower limb, th eir cutaneousbranches an d th e muscles which they suppl y.

40 NERVES OF THE LOWER LIMB

..Fig.59 The ap proximate area within which sensory changes may be found in lesion s ofthe la teral cutan eous nerve of the th igh. Usua l area sha de d. with dark blue line; largea rea indicated with light blue line .

...Fig_60 The approximate area with in which sensory changes may be found in lesions ofthe femoral nerve. (The distribution of the intermed iate and medial cutaneous nerves ofthe thigh and the saphenous nerve.)

NERVES OFTHE W WER LIMB 41

Fig. 61 The approximate area within w hich sensory changes rna)' be found in lesions ofthe obturator nerve.

Fig.62 The approximat e area w ithin w hich sensory changes may be found in lesions ofthe post erio r cutaneous nerve of the th igh.

42 NERVES OF THE WWER LIMB

Fig. 63 The app ro ximate area within w hich sensory changes may be found in lesions oft he trunk of the sciat ic nerve. (Modif ied from M.R.e. Special Report No. 54, 1920.)

Fig.64 The approximate area within which sensory cha nges may be found in lesions ofbot h th e sciat ic and th e posterior cutaneous nerve of the thigh.

NERVES OFTIIE LOWER LIMB 43

Fig. 65 The approximat e area within which sensory changes may be found in lesions ofthe common peroneal nerve above the or igin of the superficia l peron eal nerve. (Modifiedfrom M.R.C. Special Report No. 54, 1920.)

JFig. 66 The approximate area within which sensory changes may be found in lesions ofthe deep peroneal nerve.

44 NERVES OF THE LOWER LIMB

Fig . 61 The approximate area within which sensory changes may be found in lesions oft he sural nerve.

Fig.68 The approximate area within which sensory changes may be found in lesions ofthe t ibial nerve. (Modified f rom M.R.C. Special Report No. 54, 1920.)

NERVES OF TH E LOWER LIMB 45

SURAL NE RVE -----i

LATERAL PLANTARNERVE

--- MED IAL PLANTARNERVE

y'-- - - SAPH ENOUS NERVE

+- - - - - CALCANEAL NERV E

Fig . 69 The approximate areas supplied by the cutaneous nerves to the sale of th e foot.

46 NERVES OFTHE LOWER LIMB

J}

Fig .70 Iliopsoas (Branches from l 1, 2 and 3 spinal nerves and femo ra l nerve; l l , L2, l3)

The pat ient is fl exing the th igh at the hip against resist ance wi th th e leg fl exed at theknee and hip .

Fig . 71 Qu adriceps Femoris (Femoral nerve; 12. L3, L4)

The patient is extending t he leg against res istance with the limb flexed at the hip an dknee. To detect slight weakness. the leg should be fully flexed at the knee.Arrow: t he muscle belly of rect us femor is can be seen and felt .

NERVES OF TI lE LOWER LIMB 47

,

I

Fig .72 Adductors (Obt urator nerve; L2, l3, L4)

The patient lies on his back wi th the leg exte nded at the knee. and is adduct ing th e l imbagainst resistan ce. The muscle be llies can be fel t .

•

I

Fig.73 Glu t eus Med ius and M in imus (Super io r g lut eal nerve; L4. lS . 51)

The pat ient lies on his back and is internally rotating the thigh against resistance with thelimb flexed at t he hip and knee.

48 NERVES OFT HE LOWER LIMB

Fig. 74 Gluteus Medius and Minimus and Tensor Fasciae Lat ae (Superior gluteal nerve; l 4,LS, 5 1)

The pa t ien t lies on his back with the leg extended and is abducting the limb againstres istance. Arrows: t he muscle be llies can be felt and sometimes seen.

Fig.7S Gluteus Maximu s (Infer ior g luteal nerve; l S. $1. 52)

The patie nt lies on his back w it h t he leg exte nded at the knee a nd is extending t he limb att he hip ag ainst resistan ce .

NERVES OFTHE LOWER LIMB 49

Fig. 76 Hamstring Muscles (Sciatic nerve. Semitendinosus. semimem branosus and biceps;L5. S1. S2)

The pa tient lies on his back with the limb flexed at the hip and knee and is flexing the legat the knee ag ainst resistance.

Fig.77 Hamstring Musd es (Sdetic nerve . Semitend inosus, semimembranosus and biceps;l5, 51. 52)

The pat ient lies on his face and is flelCing the leg at the knee against resistance.Arrows : t he t endons of t he biceps (laterally) and semitendinosus (medially) can be feltand usua lly seen.

SO NERVES OFTHE LOWER LI MB

•

I

Fig. 78 Gastrocnemius (Tib ial nerve; 51, 52)

The patient lies on his back w ith th e leg extended and is plantar-flexing the foot aga instresist ance . Arrow: the muscle bell ies can be seen an d felt. To detect slight weakness. th epatient should be asked t o stand on one foot. ra ise the heel fr om the gr ound andma inta in t his position .

Fig. 79 Soleus (Tibia l ne rve; 51, 52)

The patient lies on his ba ck with th e limb flexed at the hip and knee and is plantar-f lexingthe foot against resistance . The mu scle be lly can be felt and some tim es see n.Arro w: t he Ach illes t endon.

NERVES OF THE LOWER LIMB 51

f ig.80 Tibia lis Post e rior (Tibial ne rve; l4. lS)

The patient is inve rting t he foot aga inst resist ance .Arrow: the tendo n can be seen and fe lt .

Fig. 81 Flexor Dig itorum l ong us. Flexor Hettuos Longus (Tibial nerve; l 5, 51, 52)

The pat ient is flexing the toes against resistance.

52 NERVES OFTHE LOWER LIMB

Fig.82 Small muscles of th e foot (medial and lateral plantar nerves; 51, 52)

The pat ient iscuppi ng the sole of the foot; the small muscles can be felt and someti messeen.

f ig.83 Tibialis Ante rio r (Deep peronea l nerve; L4, LS)

The pat ient is dorsiflelCing the foot against resistance.Arrows : the muscle belly and its tendo n can be seen and fe lt.

NERVES OF TIlE LOWER LIMB 53

Fig. 84 Extensor Digitorum Longus (Deep peroneal nerve; l 5, 51)

The patie nt is dorsifl exing the toes ag ainst resistance . The ten dons passing to the lateralfour toescan be seen and felt .

54 NERVES OF THE WWER LIMB

Fig.85 Extensor Hattucts Longus (Deep peroneal nerve; L5, S1)

The patient is dorsiflexing the distal phalanx of the big toe against resistance .Arrow: the tendon can be seen and felt .

NERVES OF TIl E LOWER LIMB 55

Fig.86 Extensor Digit orum Brevis (Deep peroneal nerve; LS, 51)

The patie nt is dorsiflexing the proxima l phalanges of the toes against res istance .Arrow: the muscle belly can be fe lt and sometimes seen.

(

Fig.87 Peroneus l ongusand Brevis (Superficial peroneal nerve; r s. 51)

The pati ent is evert ing th e foot against resist ance. Upper arrow: th e tendon of peroneusbrevis. Lower arrow: t he tendon of peroneus longus.

C6 ,-_~

DERMATOMES

C'T2

13

T'

T5

T7

T6

T9

TID

T11

Ll

T12

Fig . 88 Approximate distribut ion o f dermatomes on the anter ior aspect of t he upperlimb.

Fig. 88-91 show the approx imate cutaneous areas supp lied by each spina l root . There isconsiderable variat ion and overlap between der matcmes, so that an isolate d root lesionresults in a much smalle r area of sensory imp airment than is indicated in these diagrams.

This var iation also applies t o t he innervat ion of t he f ingers, but th e t hu mb is usuallysupplied by (6 and the little finger usua lly by (8 (see Inouye and Buchthal (1977) Bra;n100: 131- 748).The heavy axial lines are usually more consist ent, show ing the boundarybetween non consecutive dermatomes.

DERMATOMES 57

C4

T12,/ ~

L1

Fig.89 Approximate dist ribut ion of der matomes on the posterior aspect of the up perlimb.

58 DERMArOMES

Tt o

Tll

Tt 2LI

L2

ISSr:>' SJ

l3

l3S2

Il5

I

S2

S,

l4

l4

l5

Fig_90 Approximate distribution of dermat omes on the lower limb.

52

L3

53

L2 L2

53

DERMATOMES 59

L3

52

L2

Fig. 91 Approximate distr ibution of dermatomeson th e perineum

NERVES AND MAIN ROOT SUPPLY OF MUSCLES

The list given be low does not include a ll the muscles inne rvated by th ese nerves, but onlythose more commonly tested , eithe r clinica lly o r electr ica lly, an d shows the order ofinnervation.

Trice ps

Upper limb

Spinal Accesso ry NerveTrapezius

Brachial PlexusRhomboidsSer ratus anteriorPectoralis ma jor

Clavicular }Ste rna l

Supraspin atusInfrasp inat usl at issimus do rsiTeres majo r

Axillary NerveDeltoid

M usculocu taneous NerveBiceps8rachial is

Radial Nerve

!l ong head ]lateral he adMedia l head

BrechioradialtsExtensor carpi rad ialis longus

Posterior Interosseous NerveSupinatorExtensor carpi ulnar isExtensor dig itorumAbductor pollicis longusExtensor pollicis longusExtensor poll icis brevisExtensor indicis

M edian NervePronator teresHexer carpi radia lisFlexor di git orum superf tctensAbd uctor po llic is brevisHexo r pollicis brevis"Opponens pctnctslumbricals I & II

Sp inal Roots

0 .(4

( 4, ( 5( 5, (6, C7

(5, ( 6cs. (7, C8(5, (6(5. (6( 6, 0. C8(5, ( 6, C7

CS, C6

(5, ( 6

(5, (6

( 6, ( 7, C8

( 5. C6( 5. ( 6

( 6, C7C7, ( 8C7, (8(7, (8(7, (8(7, ( 8(7, C8

( 6, (7C6, (70 , C8, T1C8, 11C8, 11C8, 11C8, 11

NERVES AN D MAIN ROOT SUPPLY OF MUSCLES 61

Quadricepsfemo ris

Anterior Interosseous NervePronator quadratusFlexor digitoru m profundus I & IIf lexor pollicis longus

Ulna r NerveFlexor carpi u lna risFlexor dig itorum profundus III & IVHypothenar musclesAdductor pall idsFlexor palli cis brevisPalmar int erosse iDorsal interosseil umbr icals III & IV

l ower limb

Femoral NerveIliopsoa s

Rectus femoris ]vestus taterehsVastus inte rmed iusVast us med ia lis

Obturator NerveAdd uctor longu5Adductor magnus

Superior Gluteal NerveGluteus med us and mi nimusTensor fasciae latae

In ferior Gluteaf NerveGluteus maximus

O , C8a , C8a , ( 8

0 , C8, 11C7, (8C8, T1C8, T1C8, T1C8, T1C8, T1C8, T1

Spina l Roots

u . 12, L3

L2. l3, l4

12. l3, l 4

l 4. L5, S1

l 5, 51, 52

Sciatic and Tibial Nerve sSemit end inosusBicepsSemimembranosusGastr ocnem ius an d soleusTibialis posteri orFlexor digitorum longusAbductor hallu cisAbduct or digiti min imiInterossei

Small mu sclesof foot

l5 , S1, S2l5, 51, 52l 5, 51, 5251, 52l4, l 5i s , 51, 52

51, S2

Sciat ic and Common Peroneal NervesTibi alis ant eriorExtensor d ig itoru m longusExtensor hatlucis lo ngusExte nsor d ig itorum br evisPerone us long usPeroneus br evis

l 4, l5l5, 51l5, 51l5, 51l 5, 51l5. 51

* Flexor pollicis brev is is often supplied wholly or partially by t he ulnar nerve.

COMMONLY TESTED MOVEMENTS

Movem ent UMN Root Refl e x Nerve Muscle

Upper /imb

Shou lder abduction ++ C5 Axilla ry Delto id

Elbow f lexion (5/6 + Musculocutaneous BicepsC6 + Radia l arecbtor adtens

Elbow extension + C7 + Radia l Triceps

Radial wrist extension + C6 Radial Ext ensor carpirad ia lis longus

Finger extension + C7 Poste rior Extensorinterosseus ner ve d igit orum

commu nis

Finger f lex io n C8 + Anter io r Flexor polli dsint erosseu s nerve longus + Flexor

d igit orumpro fundus(index)

Uln ar Flexor d ig it orumprofund us(r ing + little)

Finger abduction ++ T1 Ulnar First do rsalinterosseous

T1 Median Abductor po ll icisbrevis

Lower limb

Hip fl exion ++ L1 /2 Iliopsoas

Hip adducti on L2I3 + Obturat or Addu ctorsHip extension L51S1 Sciat ic Gluteus

ma ximu s

Knee f lexion + 51 Sciat ic Hamstrings

Knee extensi on L3/4 + Femoral Quadriceps

Ankle dorsifl exion ++ L4 Deep peroneal Tib ial is anter ior

An kle eversion LS151 Superf icial peroneal Peronei

Ankle plantarflexi on S1 152 + Tib ial Gastrocnemius,soleus

Big toe exte nsion L5 Deep peroneal Extens or hellucislongus

The t able shows some commo nly t ested movem ents, the principal muscle invo lved wi t h itsroots and nerve supply. The column headed UMN indicat es those movements whic h arepreferentially w eak in upper motor neuron lesions.