Partial Forward Dislocation op the Head op the Humerus, 
or Backward Displacement op the Tendon op the Long 
Head op the Biceps Flexor Cubiti—{Replaced After Tij$ 
Lapse of One Month. By David Prince, M. D., of 
ville, 111. \/^s 
[Reprinted from the St. L»uis Med. and Surg. Journal, November, 187 9 f 
John Lidell Baker, of Barry, 111., aged seventeen, fell from a 
loaded wagon which he was driving, and a hind wheel is sup- 
posed to have passed over his chest and shoulder. After a short 
period of insensibility he rode to the house and had liniment ap- 
plied, not knowing that there had been a displacement. 
One month elapsed before the patient was examined with 
care, when it was discovered by his father, Dr. A. C. Baker, that 
the head of the humerus was too far forward. On careful exam- 
ination it was found that the axis of the humerus corresponded 
with the forward position of the head of the humerus, making it 
plain that there had been no fracture. 
The antero-posterior movement o£ the humerus was good, 
whether passive or by volition. The outward and upward move- 
ment in the direction of the contraction of the long head of the 
biceps and of the central fibers of the deltoid could be effected 
only to a limited extent. The greater or posterior tuberosity 
impinged upon the projection of the acromion, and refused to 
slide under it, as in the normal relations of the parts. The cri- 
coid pi*ocess could be felt in its normal relation with the clavicle 
with the acromion. 
The diagnosis was made out to be displacement of the tendon 
of the long head of the biceps flexor cubiti, backward and out- 
ward over the great tuberosity, so as to lie across the glenoid 
cavity, crowding the head of the humerus forward, and restrict- 
ing its occupancy to the anterior half of the glenoid cavity. 
This implies that the insertions of the supra-spinatus and the 
infra-spinatus into the outer tuberosity of the humerus had been 
detached at the time of the injury. The detachment of the teres 
minor would permit the tendon to fall still lower, and increase 
the difficulty of reduction. The tendon being torn from its 
lodgment in the bicipital groove, and thrown over behind the 
head of the bone, would retain it in a forward position upon the 
anterior rim of the glenoid cavity. 
The reason why this accident is rare (and by some thought 
impossible), is the breadth and firmness of the muscles, which 2 
must be torn from their connection with the bone before the 
bicipital tendon can be displaced backward. The forward dis- 
placement of the tendon meets with less impediment from the 
aubscapularis muscle, the detachment of which is necessary to the 
displacement, and is therefore more frequent, though extremely 
rare in surgical literature. 
(A.) Acromion process. (B.) External face of the scapula. (C.) The 
articular surface or glenoid cavity of the scapula. (D.) The humerus. 
fE.) The insertion of the teres minor into the greater tuberosity. (F.) The 
insertion of the supra and infra spinatus, which are supposed to have been 
detached. (K.) The internal tuberosity—the groove for the tendon lying 
between the tuberosities. (H. H.) The’displaced tendon. (I.) The clavicle 
disappearing behind the head of the humerus, and reappearing to be at- 
tached to the acromion process. (J.) Open space under the acromion. 
The coracoid process is hidden by the articular projections of the seap- 
mla and the humerus. 
Entertaining this theory of the case, the rational plan of re- 
duction (under ether) was conceived to be : 
1st. The flexion of the forearm. 
2d. The outward rotation of the arm. 
Sd. Circumduction, first backward, then outward, upward, 
and lastly forward and downward. 
The first round failed to bring the head of the humerus into 
position. The second round was successful. The prominence of 3 
the head of the humerus disappeared, and the arm became capa- 
ble of all its normal movements. The result justified the theory 
of the case. The treatment resulted in nearly complete absence 
of deformity, but after the lapse of several weeks a projection 
remained over the groove in the humerus in which the tendon 
normally lies, from which it is inferred that the tendon did not 
settle into its groove, but remained upon the deposit which is sup- 
posed to have filled the groove during the thirty days between 
the time of the injury and that of the reduction. 
Besides this, the displaced tendon must have carried with it 
a portion of the capsular ligament through which it passes, to- 
gether with the distal attachment of the supra and the infra- 
spinatus. The reduction of the tendon, with its accompanying 
mass of capsule and muscle, may still have failed of a complete 
restoration of the tendon to its proper groove. 
The foregoing figui*e illustrates the conception of the case : 
The rareness of the case makes it proper to make the follow- 
ing references to the literature of the subject. I have been aided 
by Dr. J. W. Freeman in making this collection of references: 
Bryant (Surgery, first American Edition, pp. 900), in speaking 
of displacement of tendons, describes one of the peroneus longus, 
and further on says: “It is a question whether any other ten- 
don can be similarly displaced; it has been said that the long 
tendon of the biceps flexor cubiti may be, but it has never been 
demonstrated.” 
Dr. Frank II. Hamilton (Fractures and Dislocations, first edi- 
tion, pp. 567-70) quotes several authors in relation to partial 
dislocation of the head of the humerus, but he maintains that 
“such an injury as a traumatic accident has not yet been estab- 
lished and the anatomical structure of the joint renders its occur- 
rence exceedingly improbable, if not impossible.” 
Dr. Hamilton refers to the case of Sir Astley Cooper as a sub- 
coracoid dislocation. In reference to the cases of Hairgrove 
and Dupuytren, he says it is quite probable that a majority of 
these accidents were examples of rupture or displacement of the 
long head of the biceps. He quotes John Gf. Smith from Amer. 
Jour. Med. Sciences, vol. XVI, p. 219, May, 1835; from London 
Med. Gazette, and Mr. Soden, same, vol. XXIX, p. 480; from 
London Med. Gazette, July, 1841, and Dr. Alfred Mercer, Buffalo 
Med. Journal, vol. XVI, p. 641, April, 1859, and says: “By a 
number of dissections it has been shown that the head of the 
humerus can be drawn upward and forward in its socket until it 
rests against the two processes and the craco-acromial ligament.” 
The conclusion of Dr. Hamilton would be unanswerable if it 
were not supposed that the subscapularis is detached for a for- 
ward displacement on the one hand, and on the other hand the 
detachment of the supra and the infra-spinatus for a backward 
displacement. 
The case of Sir Astley Cooper (Cooper’s Lectures o* 4 
tures and Dislocations near the Joints, Am. ed. 1844, p. 352) was 
one of anterior displacement of the long head of the biceps and 
a out is given showing the result of dissection, the patient 
having some time afterward died from fracture of the skull. The 
case had been considered obscure until the dissection cleared up 
the obscurity. 
Dr. Gross (Syirgery Yol. II, p. 78, fifth ed., refers in general 
terms to ruptures and displacements of the long head of the 
biceps. 
J. Mason Warren (Surgical Observations and Cases, p. 352,) 
quotes Malgaigne as relating a case of displacement of the long 
head of the biceps giving the appearance of partial dislocation. 
Erichsen in his Surgery, Am. edition of 1878, Yol. I, p. 478, 
mentions the injury but gives no original observations. 
The only case of outward displacement of the long tendon 
of the biceps to be found in the list of writers here quoted, is 
found in the chapter by W. II. Flower in Holmes’ Surgery, (4 
volumes) vol. II, p. 573. 
In this case the long tendon of the biceps was found displaced 
to the outer side of the head of humerus, the preparation being 
deposited in the museum of St. George’s Hospital. In this case 
the coracoid process was fractured and the deltoid torn so as to 
be transfixed by the head of the bone. From these quotations 
it appears that the displacement of the long head of the biceps 
outward, without extensive injury of the joint or of its surround- 
ings, is of such rare occurrence as to be worthy of especial at- 
tention. 
From the nature of the anatomy, this displacement cannot 
take place without laceration of the capsule. This, however, 
does not imply extensive injury. It is doubtful whether a com- 
plete dislocation of the head of the humerus can take place in 
any direction without rupture of the capsule, unless there is an 
unnatural relaxation of the capsular ligament. From the facility 
of the cicatrization of the rent capsule, not opened to the air, it 
is not to be wondered at, that subsequent dissection has failed to 
reveal the occurrence of laceration in those cases in which death 
has not speedily followed the injury. It may be said as a practi- 
cal hint, that one’s diagnosis of this and other cases of rare and 
obscure displacement, is not much aided by a historical knowl- 
edge of the surgery. It is chiefly by a knowledge of the anat- 
omy that one must rely for a discernment of the relations of the 
parts in instances of obscure deformities. This case is reported 
therefore, not so much for any practical benefit to the profession 
as for making the literature of the subject more complete and to 
show from anatomical considerations that the displacement is 
rendered possible by supposing the detachment of*some of the 
muscles which are intimately connected with the capsular liga- 
ment which must itself be torn or displaced along with the ten- 
which passes through it.