minor, auricularis magnus,
superficialis colli, and su-
praclavicular.)
Neck.
Shoulder, anterior surface.
Outer arm.
(Supraclavicular, circumflex,
musculocutaneous or exter-
nal cutaneous.)
Back of shoulder and arm.
Outer side of arm and forearm
to wrist.
(Supraclavicular, circumflex,
musculo-cutaneous or ex-
ternal cutaneous, internal
cutaneous, radial).
Outer side and front of fure-
arm.
Back of hand, radial distribu-
tion.
(Chiefly musculo-cutaneous
or external cutaneous, in-
ternal cutaneous.)
Radial distribution in the
hand.
Median distribution in the
palm, thumb, index, and
one-half middle finger.
(Musculo-cutaneous or exter-
nal cutaneous, internal cu-
taneous, radial, median.)
Second J
dorsal, j
' Amer. Jonrn. Med. Sci, 1886, p. 464.
Ulnar area of hand, back, and
palm, inner border of fore-
arm. (Internal cutaneous,
ulnar.)
Chiefly inner side of forearm
and arm to near the axilla.
(Chiefly intarnal cutaneous
and nerve of Wrisberg or
lesser internal cutaneous.)
Inner side of arm near and in
axilla.
(Intercosto-humeral.)
Tkerap. Gaz., 1889, p. 314.
816
THE sunaicnv of the .spine.
Segment.
Second
to
twelfth
dorsal.
First
lumbar.
Second
lumbar.
Third
lumbar.
Fourth
lumbar.
Fifth
lumbar.
First
and
second
sacral.
Third,
fourth,
and fifth
sacral.
Fifth
sacral
and coc-
cygeal.
Muscloi.
Muscles of back and
abdomen.
Erectores spinie.
f Ilio-psoas.
i Rectus,
I Sartorius.
L
f Ilio-psoas.
Sartorius.
[ Quadriceps feraoris.
Quadriceps femoris.
Anterior part of biceps.
Inward rotators of
thigh.
, Abductors of thigh.
Abductors of tliigh.
Adductors of thigh.
Flexors of knee.
Tibialis anticus.
_ Peroneus longus.
Outward rotators of
thigh.
Flexors of knee.
Flexors of ankle.
Perouei.
_ Extensors of toes.
Flexors of ankle.
Extensors of ankles.
Long flexor of toes.
Intrinsic foot -muscles.
' Gluteus maximus.
Perineal.
Muscles of bladder, rec-
tum, and external
genitals.
Coccygeus muscles.
Rcfiex.
Epigii^trir (fourth to sev-
enth dor-sal). Tickling
mammary region causes
retraction of the epigas-
trium.
Abdominal (seventh to elev-
entli dorsal i. Stroking
side of al)d(>iueu causes
retraction of belly.
Cremasteric (first to third
lumbar). Stroking inner
thigh causes retraction
of testicle.
Patellar (third to fourth
lumbar). Striking patel-
lar tendon causes exten-
sion of leg.
Gluteal (fourth t<) fifth lum-
bar). Stroking buttock
causes dimpling in fold
of buttock.
Achilks tendou (fifth lum-
bar to first sacral). Over-
extension causes rapid
flexion of ankle, called
ankle-clonus.
Plantar (fifth lumbar to sec-
ond sacral). Tickling
sole of foot causes flexion
of toes and retraction of
leg.
Vesical centres.
Anal centres.
Sensation.
Skin of chest and abdomen, in
bands running around and
d"\\ 11 ward, corresponding to
.•^piiiiil iiLTves.
rpjuT ghitful region.
(IutL'rco.stals and dorsal pos-
terior nerves.)
Skin over groin and front of
scrotum.
(Ilio-hypogastric, illio-ingui-
nal.)
Outer side of thigh.
(Genito-erural, external cu-
taneous.)
Front of thigh.
(Middle cutaneous, internal
cutaneous, long saphenous
obturator.)
Inner side of thigh, leg, and
foot.
(Internal cutaneous, long
saphenous, obturator.)
Back and outer side of leg;
sole ; dorsum of foot.
(External popliteal, external
saphenous, musculo-cutane-
ous, plantar.)
Back and outer side of leg;
sole ; dorsum of foot.
{Same as fifth lumbar.)
Back of thigh, anus, perineum,
external genitals.
(Small sciatic, pudlc, inferior
hemorrhoidal, inferior pu-
dendal.)
Skin about the anus and coc-
cyx.
(Coccygeal.)
Thorbiirn has called especial attention to wliat he appropriately
Fig. 465.
Peculiar attitude of a patient in whom the fifth cervical nerves had been crushed (Thorburn).
terms " the fifth-root group " of muscles, and to the almost pathognomo-
I
FRACTVnES OF THE SPINE. 817
nic ])(>stiiro assumed liv tlie ])atiunt who lias had the tiftli cervical nervo
cru.shed and its imisclos paralyzed, in contrast to the position assumed in
cases of a lesion below this point. The fifth cervical nerve Supplies
chiefly the biceps, the brachialis anticus, the deltoid, and the supinators.
If these muscles are not paralyzed — that is, if the fifth cervical nerve is
uninjured and tlie lesion exists at a lower level, even so close as the sixth
nerve — the deltoid will abduct the elbow, the infraspinatus (supplied by
the fourth nerve) will rotate the humerus externally, and the biceps,
brachialis anticus, and supinator longus will flex and suj)inatc the fore-
arms, so that the patient will lie with both his arms in the characteristic
attitude shown in Fio-. 4(35 and in the right arm in Fig. 466. That is
to say, if the fracture be below the fifth cervical ner\-e, there will be
abduction of the arm, elevation and external rotation of the humerus,
with flexion of the elbow and supination of the hand.
If, however, the lesion involves the fifth cervical nerve, the deltoid
being paralyzed, the elbow will lie next the body ; the brachialis anticus
and supinator longus being paralyzed, the forearm and hand will lie
prone on the chest, as is well shown in the left arm. Fig. 466, in which
the fifth cervical nerve was in-
jured on the left side oidy. f ig- 466.
At other levels than these the
posture will not be so characteris-
tic, but the site of the injury can
be determined by ascertaining
what nuisclcs are paralyzed, and
therefore what nerves involved.
For this purpose the table (p.
815) may l)e consulted witJi ad-
vantage.
It must not be forgotten also
+ K..+ \e *!,.. .>i,..^i;+; . ,,^-t„.,,l . ...^ An attitude in a case in which the fifth cervical
tliat It tile mvelitis extends up- ,, , v, ■• ^ .v, , «. j ,
. ^ * nerve had been injured on the left side onlv
ward III the cord, the area oi nius- (Thorbum).
eular paralysis will progressively
increase after the accident ; and it is therefore of the greatest import-
ance to determine not only what muscles were paralyzed at first, but
also, from time to time, whether the paralysis has involved other mus-
cles from the extension of the myelitis, or whether the paralysis has
disappeared in some of the muscles in case of recuivery.
Secondli/, the iSitc of the Lesion can be Determined to some Extent bi/
the Area of the Cutaneous Amesthesia. — In the cervical region the table
of Mills (p. 815) will enable us to arrive with fair at-curacy at the nerves
which are involved by the area of the anaesthesia.
Starr ' has also made a study of the area of anaesthesia in the arm
(•orrcsjxinding to the spinal segments from the fourth cervical to the first
dorsal, iijclusive. Fig. 467 illustrates the diflf'e.'cnt areas as nearly as
has been ascertained. The Roman numerals refer, I, to the anaesthetic
area of skin from lesion of the first dorsal segment, and IV to VIII to
the corresponding cervical segments. His conclusions may be summar-
ized as fi)llows :
IV nipresents a part of tiic area of anaesthesia from lesion of the
' Bruin, I'lirt Ixvii., 1894, p. 481.
Vol. II.— 52
818
Till-: srjiaERY of the sriSE.
f'uiirtli cervic'ul iicrvc, wliirli, liowcvcr, \iwr- not been carofully ascertained
on account of tlie fatality of such lesions.
V (fifth cervical scirnient) includes the skin of tiie outer side of the
arm and forearm from tiie wrist to somewhat al)ove the deltoid insertion.
VI (sixtii cervical scjrnient) includes the radial surface of the iiand
from tlie middle line of the middle fin<;er anteriorlv and jxistcriorly, and
also a very narrow strij) u|) the front and back of the forearm and arm
as high as the axilla.
VII (seventli cervical segment) supplies the middle of the ])alm and
dorsum of the hand, the adjacent sides of the middle and ring finger,
Fig. 467.
v» VJ
VII VII
Areas of anesthesia in lesions of the cervical cord (Starr).
and a narrow strip up the forearm and arm to the axilla, both anteriorly
and posteriorly.
VIII (eighth cervical segment) includes the ulnar side of the hand,
the little finger, the adjacent half of the ring finger both anteriorly and
posteriorly, with another strip of skin up to the axilla.
I. The area corresponding to the first dorsal segment is a narrow one
on the inner side of the arm and forearm from the axilla to the wrist,
but does not extend on the hand.
Mr. Thorburn states, in a general way, that the outer parts of the
upper extremities correspond to the upper nerve-roots, the inner portions
to the lower. In the dorsal region the area of the ana?stliesia is gener-
ally almost horizontal, and if the injury be bilateral it will encircle the
trunk. In determining, however, the segment of the cord which has been
injured from the upper level of the ansesthesia it is very important again
FRACTURES OF THE SPINE.
819
to remember the tliet that tlic foramina between the vertebrje through
whicli tlie nerves pass, anil tlie level at whieh tlie nerves emerge from
the spinal eord, vary very nuieh in level, as is shown in Fig. 456. In
the ujiper cervical region the nerves after leaving the spinal cord descend
but very little to their foramina of exit, but as Me go farther down the
nerves pass downward for increasing distances before they make their
exit from the spinal canal. For instance, Fig. 456 shows that the tenth
dorsal nerve originates opposite tiie body of the ninth dorsal vertelira
or the eightii dorsal spine, but makes its exit below the body of the
tenth dorsal \'ertebra. In conseipience of this the upper level of the
region of the cutaneous ansesthesia will be constantly below the level of
the root of the nerve involved. IMoreover, from the lower end of the
cord, which ends at the lower border of the body of the first lumbar
vertebra, a large number of nerves come off and run down in the spinal
column to the lumbar and sacral foramina in a bundle of cords known
as the Cauda equina.
Starr ' has made a most careful study of the condition of local antes-
thesia as a guide to the diagnosis of lesions of the lower spinal cord —
that is, from the second lumliar to the fifth sacral segments of the cord
— and has combined the observations into two diagrams (Figs. 468 and
469), which will prove of the greatest value as a foundation for future
studies. His eonelusious may be summarized as folloMS :
Fi(i. 4G8.
V\(i. 469.
17/
Areas of ana-sfthcsia at vnrioiKS levels of the spinal cord, from sacral V tu lumbar II; J, sacral
V: II. sacral IV; ///, sacral III; /!', sacral I; V, lumbar V; VJ, lumbar III; 177, lumbar
II. 'after ."^tarri.
In the spinal cord the centres of control of the bladder and rectum
are always affected together, and must therefore be adjacent. Control
over these sphincters is lost when the loM'er three sacral segments are
' Amer. Jouni. of (lie Med. ScL, July, 1892, p. 15.
820 THE SURGERY OF THE SViyE.
involved, and j)rol)al)ly tlic centivs wliicli contrnl tlicin lie in the lowest
two segments. Loss of control over the sphincter nni is best determined
by the introduction of the finger, which will meet with no resistance
when the sphincter is paralyzed. The s])liincter of the bladder is not
permanently relaxed, for constant dribbling does not take jilace, but
there is only intermittent thougli unconscious dribbling as soon as a few
ounces of urine collect, lieteution of urine is nuich more liable to
occur when the lesion lies at a iiigher level. If, therefore, in a case of
paraplegia the mechanism of the bladder and rectum is not interfered
with, it is a proof that the lesion has not destroyed the lower sacral seg-
ments of the cord. This fact, with a careful determination of the area
of the ansestliesia, may enable us to make an exact diagnosis.
Figs. 468 and 469 show the cutaneous areas of an;esthesia whit'h are
caused by lesions of the nerves indicated. Each area of ansesthesia in-
cludes the smaller ones within it. The different zones are numbered in
the illustrations as follows :
I. The first zone is supplied l)y the fifth sacral segment, and includes
the perineum, the posterior part of the scrotum in males, the vagina in
females, and also the mucous membrane of the rectum.
II. The second zone, supplied by the conns me(lu]laris and the fifth
and fourth sacral segments, is heart-shaped, \vitli the point up, and in-
cludes the entire scrotum and the posterior surface of the penis, the
mucous membrane of the urethra in males, the entire genitals of the
female exce])t the outer surface of the labia niajora and the mons
Veneris. If the genital oi'gans escape, the case is one of functional and
not of organic paraplegia.
III. The third zone is sujiplied by tlie fifth, fourth, and third sacral
segments, and involves not only the buttocks, but extends down the back
of the thighs. This has been named the " saddle-shaped " area, as it
coincides with that part of the body which is in contact with the saddle
in riding.
IV. This corresponds to the first and second sacral segments, and is
similar to the third, except that it is larger in extent.
V. The fifth zone corresponds to the fifth lumbar segment.
VI. The sixth zone corresponds to the third lumbar segment. This
may hereafter l)e separated into two parts, corresponding to lesions of
the fourth and third lumbar segments. As yet the number of recorded
cases is insufficient for this distinction.
VII. The seventh zone involves the four lower lumbar segments.
It will be observed that the abdominal wall is not anaesthetic in lesions
of this segment. It is only when the first lumbar segment of the cord
is involved that the anesthesia extends to the abdominal wall.
Above the level of the second lumbar segment the zone of anaesthesia
extends around the body in a girdle.
It is impossible, at present, by the area of anaesthesia to distinguish
the lesions of that part of the cord from which the nerves of the cauda
equina arise from lesions of the cauda itself. If the fracture or disloca-
tion, however, is below the first lumbar vertebra, at which level the cord
ends, the lesion nnist be of the cauda itself.
The muscular paralysis is very slight in lower cord lesions, being
confined to the perineal muscles when the lesions arc at or below the
FRACTURES OF THE SPINE.
821
second sacnil segment. It involves tlu> anterior and posterior tibial
muscles when all the sacral segments are involved, and only involves
the movement of the liip-joint wiien the entire lumbar region is aifected.
In lesions of tlie eauda, on the other hand, pressure on nerve-roots is
often sulhcient to produce widespread paralysis when sensation is but
slightly aiieeted (Starr).
It has been thought that if sensations of touch, temperature, and
pain are not equally destroyed, it was an evidence of lesions of the cord
as distinguislied from one of the cauda, but Starr has shown that this
point is not well taken.
It must not be forgotten that each sensory nerve supplies a definite
area or l)and around the body and ni'('U,l)ut overlaps its neighbors above
and below, so much so that each region may be stiid to be supplied by
Fig. 470. Fig. 471. Fig. 472. Fig. 473.
To show the presumed distribution of the areas of eutaiieous sensibility in the lower extremities
from the second lumbar to the tirst sacral segments. The area marked in i-ross lines represents
the second lumbar; vertical /incs, the third lumbar; circles, the fourth lumbar; do^', the fifth
lumbar: the plain area below the knee, the first dorsal (Head).
two nerves. This probablv accounts for the zone of parfesthe.sia at the
border between the normal and the ansesthctic regions.
In tiie extremities the regions are not band-like, but irregular and
distorted (Figs. 470 to 473). No such overlapjung exists in the sen-
sation of i)ain or heat and cold ; hence the latter may sometimes be
utilized even to greater advantage than the tirea of tactile anaesthesia
ill determining the level of the lesion of the cord.
In some cases, besides the fracture-dislocation of the vertebrte, there
may be injury and subsequent disease of the viscera, and a knowledge
of the area of cutaneous tenderness, of the areas in M'hich consequent
herpes zoster may break out, or of the analgesia, may assist us in the
diagnosis of these additional lesions. (For this the reader is referred to
the elaborate paper and plates by Head in Brdln, Part Ixi. pp. 1-133.)
T/iinUi/, the Condition of the Bcfle.vcs. — The various reflexes and
their connection with the individual nerves are well shown in the table
of Mills (]). SI. 5). Their presence or absence will show whether the
822 THE SURGERY OF THE SPINE.
segments of the cord witli wliidi tlicy aiv (â– (innectcd are intact or have
heen destroyed. Tlic same colmiui j^ives in each instance the metliod
of prochieing tlie reflex, wlietiiei- by sudden irritation of the skin, hv
(h'awini;; a pentdl or tlie finger-nail, etc. across it, or by tapping or strok-
ing certain parts of tlie skin or striking certain tendons.
In connection with the reflexes it is of great importance to distinguish
between the effects of toial and of jMtrfird trdnfiirr.sc lesioiix of the cord
on the reflexes. Especially is tiiis important in reference to the (juestion
of operation, since the condition of tlie reflexes has been held to be an
index of the extent of the lesion, and especially whether it be a partial
or total destruction of the spinal cord. Bastian ' first clearly called
attention to these phenomena, and Bowlby,'^ Thorburn,'' and Herter''
have further elucidated the facts. Their conclusion is that in complete
tninsrerxe dcxtnictire /exiniin of the cord there will be complete muscular
paralj'sis of tlie parts below the level of the injury, complete anaesthesia
below the level of the distribution of the injured nerve, and also com-
plete and permanent abolition of the knee-jerk and other deep reflexes
on both sides ; but that in partial transverse lesions of the cord the mus-
cular paralysis and also the anaesthesia will be incomplete, and the deep
reflexes either normal or exaggerated instead of absent. The visceral
reflexes, especially those of the bladder and rectum, obev the same rule
as the deep reflexes. The superficial reflexes, while they are generally
absent in total destructive transverse lesions, are not always absent,
especially the planter reflex. Hence it is said that if immediately after
the accident the knee-jerk on both sides is absent, and remains so, opera-
tion is contraindicated.
As a general rule, there is no question that the persistent absence of
the reflexes, especially of the knee-jerks, is an evidence that the cord has
been so completely destroyed that it would not be wise to operate, and
yet there are a few happy exceptions to the rule. Thus, Schede'* reports
the case of a man who had fallen from a height and fractured the fifth
and sixth dorsal vertebra', with com])lete paraplegia and anesthesia of
the lower extremities. The patellar reflexes were absent. The next day
bed-sores were beginning over the gluteal region. Sixteen hours after
the accident Schede operated and removed the fragments which were
pressing on the cord, the dura being uninjured, but the cord being soft
and fluctuating. In two days the patient's symjitoms began to improve.
The knee-jerks Ijeeame increased, with ankle-clonus on the right side,
and the superficial reflexes scarcely increased, excepting those of the
foot-sole. When reported the functions of the bladder and rectum were
normal, and the patient was able to walk about without sujiport or pain.
His nutrition was excellent, and two mouths after his discharge he was
in first-rate health.
Hammond and Phelps^ report a case of fracture (tf the twelfth dorsal
vertebra in which " the plantar reflexes on l)oth sides were lost ; both
knee-jerks were absent ; the crcmaster reflex was present on the right
side, but lost on the left side ; both abdominal reflexes were present."
' Med.-Ckir. Tram., 1890, Ixxiii. 1.51. = Ibid, 1890, 383.
' Manehester Med. Chron., 1892, xvi. 73, and Surgery of the Spinal Cord.
* Journ. of Nerv. and Merit. Din., .June, 1891.
^Annah Surg., Sept., 1891. " Jonrn. Nerr. and Ment. Dis., 1893, xviii. 478.
FRACTURES OF THE SPINE. 823
There \va8, i)f course, paraplegia. Tlie t)peration was done nearly two
years after the injury. "A certain amount of improvement was observed
the day after the oj)eration. Tactile sense was restored on the front of
the thighs. He could follow and locate a touch accurately, but all other
forms of sensibility were absent. Gradually slight motion returned in
the left thigh, and the right tliigh became stronger than it had been.
Finally, after two months he was able to walk around with the aid of
erutches." Two years ago, at the Jefferson Hospital, I assisted my col-
league, Prof. Forbes, in a laminectomy for an old dorso-lumbar disloca-
tion in which the knee-jerks had been absent for eighteen months, but
returned within a week after the operation.
It must be confessed, however, that while, if the rule of non-interfer-
ence in cases of absent knee-jerks had lieen adhered to, these patients
would undoubtedly iiave perished, yet they seem rather to be happy ex-
ceptions to the rule, and as such reinforce it. Unquestionably, a large
part of Schede's success A\as owing to the early date of the operation —
sixteen hours after the accident.
The general conclusion, therefore, is that where jiersistent absence of
knee-jerks and otlier reflexes, except jiossibly the plantar reflex, is noted,
no operation should be done, since the injury is almost certainly so pro-
found that no good result will follow. Kegeneration of the spinal cord
even after incised wounds is not generally to be expected, and after its
total destruction is certainly not to be hojied for. Experiment upon
animals has shown that it is impossible, and clinical exjierience in man
undoubtedly confirms it.
Besides the condition of tlic reflexes as determinina- for or against an
operation, three other factors are to lie considered in connection with any
operation : first, the time when it should he done if done at all ; secondly,
the site of the lesion as influencing the decision to operate ; and thirdly,
the amount of interference which is allowable.
First, fill- Time vlioi the Operation sitmdd be Done. — C'hij)ault ' has
well sununarized the medullary lesions after fracture of the vertebrie,
and has especially insisted upon their early appearance. In all trauma-
tisms of the cord there are three serious lesions :
(rt) A first zone, consisting of that portion of the cord which is
directly destroyed. This may be of greater or less extent. It inidergoes
necrosis in consecpience of the destruction of the nerxous elements tliem-
selves. This necrosis is immediate.
(b) A second zone, both above and lielow the first, in which the
nervous elements have been injured, but not absolutely destroyed. At
the end of two or three days the nervous cells are increased in size and
their jjrotoplasm has become granular, the cylinder-axes form a sort of
chaplet, the myelin is ])roken into segments. Ciinically, this begimiing
of degeneration in immediate juxtaposition to the injured part can be
determined by noting the involvement of the motor and sensitive
centres immediately above the site of the injury. If the cause of
compression is removed, both cylinder-axes and myelin undei'go a cer-
tain amount of regeneration Iw the ninth day.' If, however, the cause
of the compression persists or the injury is sufficiently grave, the
' Eludes de Chit: medul., p. 83, note.
^ Kerestzegy and H.anns, Beitragef. Pnlh. Awil., 1892.
824 THK SVUdF.HY (IF THE SI'INK
(k'striictiuii of the cord in tliis zinic i.s piTiiiaiu'iit and is i'oliowcd hy
stilerosis.
(c) Soeondarv ilcironerations set in at a very early period. Tiie.se are
caused not by tlie direct iiijiirv to the nervous elements, hut probably by
their separation from their trophic centres. These deji'enerations exten<l
both al)ove and below the site of the lesion, and begin as early as the
fourth day, and (continue to extend for a number of months. They
follow the general rule of the Wallerian degeneration ; that is to say,
from the site of the lesion downward the motor fibres degenerate, and the
sensory in the reverse direction. The early date at which these altera-
tions have been well recognized, especially by ex|ierinu'nt upon animals