Thank you Karen! I copied this portion of the disorders it is a hard read form me but my HD thinks alot of this relates to what Maddie has.
Complete traumatic disruption of the elbow joint usually results in the radius and ulna being displaced laterally to the humerus (lateral luxation) (Fig. 23-7).(9) This occurs because the medial condyle of the distal humerus is larger, preventing the radius and ulna from moving medially. The clinical picture is that of complete instability of the joint with deformity. The animal holds the leg in abduction with external rotation. The level of pain evidenced by the animal is quite variable but seems to diminish with time. Palpation of the limb reveals a large prominent medial condyle with loss of normal features on the lateral aspect. Radiographs in two views prove the diagnosis and may rule in or out additional fractures.
FIG. 23-7 Lateral (A) and cranial-caudal (B) views of a lateral luxation of the elbow joint.
CLOSED REDUCTION
Reduction of a dislocated elbow may be difficult. Knowledge of the normal bony anatomy is necessary to reestablish an intact joint. Closed manipulation will often lead to successful reduction if swelling is not too severe.
Prolonged manipulation is not beneficial to the patient's joint, and open reduction should be considered if closed manipulation is not successful in a short time. To accomplish a closed reduction of a lateral luxation of the elbow joint, the joint is flexed to 90deg and the anconeal process is rotated medially (internal rotation of the radius and ulna) to interdigitate into the supratrochlear foramen. The leg is gradually extended with a lateral to medial force applied to the radial head while a medial to lateral force is applied to the medial condyle of the humerus. Simultaneously with these medial and lateral forces and gradual extension of the limb, the radius and ulna are internally rotated after hooking the beak of the anconeal process into the trochlear groove to snap the joint back into position. If successful in reduction, the joint should be carried through a full range of motion. If completely stable at this time, a soft bulky bandage can be applied to the elbow joint to ensure continued extension. If unstable in flexion, the joint should be immobilized in a Schroeder-Thomas splint in extension for 10 to 14 days. Occasionally the joint will be completely unstable, requiring open reduction with soft tissue reconstruction.
OPEN REDUCTION
Open reduction of elbow luxations is usually carried out through a lateral incision through the anconeus muscle. Following debridement of the joint, reduction is carried out via the method described for closed reduction. A bone elevator may be used carefully within the joint surface if necessary. Rarely open reduction is not successful through this approach. To obtain reduction, the lateral approach is combined with proximal ulnar diaphyseal osteotomy, which allows the luxation to be reduced easily. Special attention to closure of the soft tissues will result in good stability of the joint. Postoperative immobilization, usually in extension, is necessary for 10 to 14 days.
CONGENITAL AND DEVELOPMENTAL DISLOCATION OF THE ELBOW
Congenital luxation of the elbow usually occurs in the smaller breeds of dogs. The dislocation may occur as a complete luxation, as is seen with traumatic luxation, or may be found with luxation of the radial head with an intact ulnar articulation or with ulnar subluxation. Congenital dislocation can also be seen with an intact radial humeral articulation with subluxation or dislocation of the ulna. The ulnar subluxation in these cases has only a rotatory component that is the cause of the dislocation.
Congenital luxation of the elbow in the dog is reported to be associated with aplasia or hypoplasia of the medial collateral ligament as well as a functionally annular ligament.(1) It has been suggested but not proven that this condition is heritable.
The treatment of these problems is often based on the general wellbeing of the animal and on expectatation for reasonable function of the involved limb.(2,5) Often the anatomical bony structures are changed in such a way that the joints are incongruent when reduced. The absence of associated soft tissues may make reconstruction impossible, as is often the case with complete dislocation. Although not reported, arthrodesis might be a method that would allow functional stabilization of the elbow.
With an intact radial humeral joint, the ulna can be repositioned following proximal ulnar diaphyseal osteotomy and reduced into position. Stabilization is accomplished by attachment of the ulnar segment to the proximal radius using pins or small screws for fixation. When the radial head is luxated, appropriate treatment depends on the radiographic appearance of the proximal radius and ulna. Correction must be achieved, trying to maintain leg length. If the diaphysis of the radius is straight, proximal ulnar osteotomy is performed. If deviation occurs in the radius, only osteotomy of the proximal radius is carried out at the level of the curvature, and the radial head is repositioned properly after shortening the segment to allow it to be inserted properly. In most cases of radial head luxation, the radial head will have a spherical joint surface. This surface will not maintain proper congruency with the humeral condyles and will have to be contoured appropriately. This reshaping of the radial head will remove joint cartilage and may have a marked effect on the outcome of the procedure.
The ease with which little dogs manage to get around on three legs makes the corrective procedures uncommon, but the successes seen encourage further experience with surgical reconstruction.
Developmental dislocation may be difficult to separate from congenital dislocation except in relation to the age of onset. Animals may be of any size and develop subluxations first. If unchecked, dislocation of the elbow occurs later, usually following some form of traumatic insult to the growth physes of the proximal or distal radius and ulna.(4,7,5)
Premature arrest of ulnar growth is usually associated with lateral deformity of the forepaw but may be associated with luxation of the elbow or possible fracture of the anconeal process. In these cases, the ulna stops growing while the radius may continue to grow, actually pushing the humeral condyles out of position caudally, or the radial head may slip laterally and luxate in this manner.
