The term "Internal Derangement" which is employed
as the title of this Thesis has become classical, and was
first used by that distinguished surgeon,Mr Hey of Leeds
in the year 1803 in a paper forming the subject of Chapter 8 in the first Edition of his "Practical Observations
in Surgery". It has been thought advisable therefore, to
retain this term which however has now a wider signification than that given to it by Mr Hey. The term sufficiently explains itself,implying that there is some disturbance of the internal component parts of the joint,
producing certain symptoms to be afterwards enumerated,
and leading one to suspect the existence of some internal lesion in the joint.A very brief summary from Hey's
paper enables us to appreciate his definition of the title."This joint is not unfrequently affected with an
"internal derangement of its component parts,and that
"sometimes in consequence of trifling accidents. The disease is,indeed,now and then removed,as suddenly as it
"is produced,by the natural motions of the joint without
"surgical assistance,but it may remain for weeks or months
"and will then become a serious misfortune,as it causes
"a considerable degree of lameness."This disorder may happen with or without contusion.
"In the former, the symptoms are equivocal till the effects of the contusion are removed. When no contusion
"has happened, or the effects of it are removed, the joint
"with respect to its shape appears to be uninjured. If
"there Is any difference from its usual appearance, it is
"that the ligament of the patella appears more relaxed
"than in the sound limb. The leg is readily bent or extended by the hands of the surgeon, and without pain to
"the patient at most,the degree of uneasiness caused by
"this flexion or extension is trifling. But the patient
"himself cannot freely bend or perfectly extend the limb
"in walking; he is. compelled to walk with an invariable
"and small degree of flexion. '"The complaint which I have described may be brought
"on, I apprehend,by any such alteration in the state of
"the joint as will prevent the condyles of the os femoris from moving truly in the hollow formed by the semi-lunar cartilages and articular depressions of the tibia.
"An unequal tension of the lateral or ,cross ligaments of
"the joint,or some slight derangement of the semi-lunar
"cartilages may probably be sufficient to bring on the
"complaint".It is evident then that Hey regarded the complaint as one due to some interference with the proper movement
of the femoral condyles upon the tibial articular surfaces, and that such interference might "be due, inter alia,
to some derangement of the semi-lunar cartilages and he
was unquestionably right, though he had no opportunity of
examining the interior of joints so affected.Symptoms closely resembling those produced by derangement of one or other semi-lunar cartilage may be dependent upon entirely different lesions,so much so,that
it becomes often very difficult to diagnose the exact condition before the joint is opened for the purpose of treatment. Consequently I have preferred to give a wider bearing to the title "Internal Derangement" than that indicated by Hey and for purposes of description have divided
this essay into two parts from the pathological side, thus
grouping all the morbid conditions which may give rise
to symptoms more or less similar and which should be associated with this term "Internal Derangement"I. A lesion of one or other Semi-lunar Cartilage.
II. Loose and pedunculated bodies,hypertrophied synovial fringes,new growths etc.The subject cannot be so divided clinically because One
lesion in some of its symptoms so frequently corresponds with, another, rendering an exact diagnosis sometimes very
difficult. This is not a matter of very much importance
so far as immediate treatment is concerned, though the
prognosis may be affected by what is found. If any attempt be made to divide the subject clinically, a division
into traumatic and non-traumatic lesions would be of considerable value to the clinician,because with the exception of certain loose bodies which might be traumatic,
but whose origin from injury is disputed, the morbid conditions in group I are produced by traumatism, those in
group II are not. Undoubtedly, the condition is one of
very considerable surgical importance, as a person may
become more or less permanently disabled, he may require
to give up his occupation altogether or only be able to
work for short periods,and in the young it may be necessary to withhold from all active exercise in the shape
of football, cricket, cycling, and other forms of athletics.An attempt will be made to give a succinct account
of the various pathological conditions that may occur,
to define as clearly as possible the symptoms,endeavouring to differentiate by them the lesion that exists, to
discuss the different methods of treatment, and to show
what benefit may be derived therefrom.Such results have been arrived at by a study of the
literature of the subject,by the examination of pathological material which has been put at my disposal,and by
the study of a series of cases which have come under my
own observation, and I would take this opportunity of
acknowledging my indebtedness to Professor Annandale for
the kind way in which he has allowed me to make use of
the patients under his care,and for the valuable assistance I have thus obtained, and at the same time to thank
Professor Sir William Turner for leave to examine the
material bearing upon this subject in the Anatomical
Museum of the University of Edinburgh.The work has been carried on in the University Clinical Surgery department of the Royal Infirmary, and part I in a less extended form has already been the subject matter of a short paper in the Edinburgh Hospital Reports,
vol.II,1894
