Tendon

“ Tendinitis.—German authors describe an inflammation of tendon as distinguished from inflammation of its sheath, and give it the name tendinitis. It is met with most frequently in the tendo-calcaneus in gouty and rheumatic subjects who have overstrained the tendon, especially during cold and damp weather. There is localised pain which is aggravated by walking, and the tendon is sensitive and swollen from a little above its insertion to its junction with the muscle. ”

“ There are no essential alterations of muscle or tendon except those secondary to the contraction of the joint—namely, an undue tension and prominence of the extensor tendon over the metatarso-phalangeal articulation, and an adaptive deficiency of length in the flexors, which are prevented by the permanently bent state of the articulation from keeping pace in growth with the osseous structures. ”

“ Arises by a short tendon from the anterior spine of the ilium, near its union with the pubis. The muscle swells quickly to a thick belly which, lying under the skin on the forward and inner side of the upper thigh, is again reduced to a small, flat tendon which extends abruptly over the anteromedial surface of the knee joint to its outer side; it then passes through the complex of tendons of the femoro-tibialis muscle, beneath which it unites with the tendon of origin for the peroneus posterior muscle. ”

“ The tendon is continued proximad on the inner surface of the muscle and forms a smooth firm surface by which the muscle glides over the dorsal border of the ischium. Into the inner surface of this tendon near its insertion the tendon of the gemellus inferior is inserted. ”

“ Insertion.—The slender tendon, which begins along the medial edge of the distal part of the belly, passes through the groove on the posterodistal surface of the first metatarsal and onto the proximal end of the ventral surface of the hallux; the tendon widens considerably and attaches by its edges to the ventral surface of the proximal end of the first phalanx, forming a short "tunnel" through which the tendon of M. flexor hallucis longus passes.
Innervation.—The paraperoneal branch of the tibial nerve sends one or two twigs into the proximal part of the muscle (but distal to the hypotarsus) . ”

“ Here, alone, at the distal portion of the tendon, occur muscular fibres, but these are unstriped, belonging to the category of cutaneous muscles. We have here the interesting fact that a muscle (portion of the triceps humeri of the reptiles) has been reduced to a tendon, which in a secondary way has become connected with cutaneous muscles, which, when strongly developed, represent its belly. ”

“ Then, by moving the hand down on the inside of the arm toward the elbow, the lessening muscle may be readily traced until it terminates in a tendon, of much less size than the muscle, but of great strength, which is inserted into the bone just below the elbow. As the fore-arm is drawn up, and especially if there be a weight in the hand, the tendon may be felt just within the elbow-joint, running toward the point of insertion. ”

“ When bringing a tendon to its new point of attachment, it should pass in as straight a line as possible, avoiding any bend or angle which might impair its action. Fat is the best medium for the transplanted tendon to traverse, as it acts as a sheath and prevents the formation of adhesions which would interfere with the function of the new tendon. All deformity must be corrected before transferring the tendon ”

“ Pars postica forms a short narrow tendon that fuses to the lateral part of the tendon of pars lateralis, forming the lateralmost part of the patellar tendon. A broad flat vinculum extends from the lateral surface of the femorofibular fascia (defined under M. flexor perforans et perforatus digiti II) to the deep surface of the lateral part of the patellar tendon; a similar vinculum extends from the medial surface of the internal condyle to the deep surface of the medial part of the patellar tendon. ”

“ In most animals, there is connected with the muscles another kind of structure called tendon, which consists in a white substance very different from muscles, but having a fibrous structure. Although tendons are not necessary to the action of muscles, yet there are several advantages derived from them; they occupy much less room than muscles, and can be placed in greater numbers around the joints, so as to preserve the beauty and uniformity of the limbs. ”

“ Such injury happens often in horses, in what is called breaking down. In them the tendon is occasionally snapped entirely through, and the ends widely separated. The same occurs in the human subject. Separation of the muscular fibres, however, is rare; laceration of the tendon itself, or separation of the tendon from the muscle, is more common. The yielding of the broad tendons on the upper and fore, lateral and under parts of the abdomen, affords an example of laceration of tendinous fibre from violent exertion. ”

“ In a young and fat child, where the inner edge of the tibia cannot be distinctly felt, the best guide to the tendon is a point midway between the front and the back of the ankle. An incision in front of this point might injure the internal saphena vein; behind this point, the posterior tibial artery.
119. Tendons behind outer ankle.—Behind the malleolus externus we feel the two peroneal (long and short) tendons. They lie close to the edge of the fibula, the short one nearer to the bone. ”

“ When muscles contract forcibly, they pull upon the tendons which transmit the movement to the bones to which they are attached. Tendons may be compared to ropes or cords which, when pulled, are made to act upon distant objects to which one end is fastened. Sometimes the tendon runs down the middle of a muscle, and the fibers run obliquely into it, the tendon resembling the quill in a feather. ”

“ Instead of being thus attached directly to the bone, they end in what we call tendons. These tendons are hard and strong, and a very small tendon will lift as much without breaking as quite a large muscle. The muscles are soft and would have to be attached over a large area in order to secure the required strength. The tendons, being so much stronger than the muscles, can be attached to a very small area and yet secure the same amount of power as would result from attaching the muscle itself.
The tendons pass directly into the periosteum, the thick, strong covering of the bones. ”

“ Origin by a strong tendon from the caudal three-fourths of the symphysis of the ischium and pubis. The tendon may extend caudad of the symphysis in the middle line to the level of the tuberosity of the ischium. For about its first centimeter the tendon is common to the two muscles of opposite sides and gives origin on two sides to the fibres of the adductor femoris. The common tendon divides into two which pass laterad, each ending in a convex border from which the muscle-fibres spring. ”

“ The long tendon, as it is called in the foot, which bends the first joint of the toe, passes through the short tendon which bends the second joint; which course allows to the sinews more liberty and a more commodious action than it would otherwise have been capable of exerting. ”

“ The pressure of the ligament constrains the tendons; the tendons react upon the pressure of the ligament. It is impossible that the ligament should ever have been generated by the exercise of the tendons, or in the course of that exercise, forasmuch as the force of the tendon perpendicularly resists the fibre which confines it, and is constantly endeavouring not to form but to rupture and displace the threads of which the ligament is composed. ”

“ Every effort of contraction in the long muscles is concentrated upon a single point, the tendon. In most of the broad muscles, on the contrary, the attachments being made at two sides by different points, all the fibres do not contribute to the same end. ”

“ There are two flexor tendons of the phalanges,—namely, the superficial (perforatus tendon) and the deep (perforans tendon) .
Fig. 15.
Right forefoot seen from behind: a, lower end of the perforans tendon, cut through and hanging down, so that its anterior surface is visible; a′, lower expanded end (plantar aponeurosis) of this tendon, which attaches itself to the semilunar crest of the os pedis; a′′, shallow groove which receives the slight elevation on the under surface of the navicular bone; a′′′, piece of the perforans tendon enclosed by the ring formed by the perforatus tendon ”

“ Operation.—The foot being held at about a right angle with the leg, the operator should pinch up the skin over the tendon, introduce the knife flatwise, a little to one side of the tendon, till its point is nearly projecting at the other, then turn the edge on the tendon and cut inwards with a sawing motion till the tendon gives way with a distinct snap, and the foot can be completely flexed with ease. ”

“ Treatment.—If the injury be seen in the early stage and there is no loss of substance at the point of lesion, it may be treated satisfactorily by fixing the finger, hand, and wrist in full extension, to allow the passive approximation of the divided extremities of the tendon; but should the case not come under notice until a later period it will be necessary to cut down and suture the tendon. If there is loss of substance and the two ends of the tendon cannot be brought together, the treatment must vary with the position of the injury. ”

“ The affected finger becomes red, painful, and swollen, the swelling spreading to the dorsum. The involvement of the tendon sheath is usually indicated by the patient being unable to flex the finger, and by the pain being increased when he attempts to do so. On account of the anatomical arrangement of the tendon sheaths, the process may spread into the forearm—directly in the case of the thumb and little finger, and after invading the palm in the case of the other fingers—and there give rise to a diffuse cellulitis which may result in sloughing of fasciæ and tendons. ”

“ Origin by a flat tendon from the transverse processes of the second and third caudal vertebræ. The muscle forms a flat band which passes distad along the middle of the lateral side of the thigh over the pelvis and caudad of the great trochanter. At the middle of the thigh it ends in a very thin tendon. ”

“ As it is the only point of support, if you raise it from the ground by paring it, there arises an inordinate extension of the tendon, caused by the pushing of the coronary against the navicular bone, as has been mentioned above, and which, being repeated at every step the animal takes, fatigues it, and induces inflammation. ”