Treatment options for hip laxity (Proceedings)
It is important to understand that when a dog presents with a dog with hip laxity (hip dysplasia) with or without secondary degenerative changes, that there is not one single way to manage every patient. Initially, one must decide if a particular patient is better suited for medical or surgical options. Medical management is identical to management of any other joint OA. If it is determined that surgery is a potential option, then many other factors about the case must be included in the decision of which surgical procedure is best for that particular animal. The goal of this lecture is to give you guidelines which will help you determine which surgical procedure may best suit a given dog in your practice. For ease of description and clarity, I will divide the discussion into immature and mature patients, with subdivisions depending on the degree of secondary degenerative joint disease. It must be stressed that concurrent orthopedic or neurologic disorders usually will preclude them from any of these procedures. Once those concurrent problems have been addressed, then possibly the dog may be considered for further coxofemoral joint surgery.
Immature DogsDogs presented to your practice with pain and dysfunction caused by hip laxity can initially be divided into two groups: those which radiographically have degenerative joint disease(DJD)/Osteoarthritis(OA) present and those who don't. This differentiation is important as most surgeons feel that the presence of DJD/OA severely diminishes the positive long term effects of the pelvic or femoral osteotomy procedures.
Dogs without secondary DJD/OA:
In this group of animals, the possible surgical procedures include a pelvic osteotomy (most common is the triple pelvic osteotomy), the intertrochanteric osteotomy, femoral head and neck excision (FHO), and for the temporary relief of pain, the pectineus tendon/muscle transection.
Dogs with secondary DJD/OA:
In this group of animals, the possible surgical procedures include the FHO, and the pectineus transection for the relief of pain. Another approach is to manage these dogs with medical management until they are skeletally mature (10-12 months) and perform a total hip replacement.
This group of animals usually already has DJD/OA, and thus the potential use of the pelvic or femoral osteotomies is limited. However, there is the occasional 1 to 1.5 yr old dog that will fit the criterium for one of these procedures. In this group, the most common procedures recommended are the total hip replacement, and the FHO.
The procedures in which osteotomies of the pelvis are performed are designed to improve the congruity of the coxofemoral joint. The most common of these procedures is the triple pelvic osteotomy (TPO) and more recently the juvenile pubic symphysiodesis (JPS). As previously stated, the TPO is best suited for treating the young, growing dog with clinical and radiographic signs of hip dysplasia and no radiographic evidence of DJD/OA. Thus candidates are usually under 10 months of age, medium to large size dogs with coxofemoral joint laxity. Once a patient has been identified as a potential candidate, surgery should be done as soon as possible to prevent further deterioration of the hip and appearance of radiographic evidence of DJD. Whether staged unilateral procedures (2 to 4 weeks apart) or bilateral procedures should be done is currently an area of debate with some surgeons on each side of the issue. The goal of these procedures is to improve clinical function (reduce pain, and stabilize the joint) and to slow the progression of DJD over the life of the patient.
Although published data is limited on the results of this procedure, that data is available is very positive with improvements in subjective and objective measurements of gait function. Also there is some evidence that there is a slowing of progression of DJD in dogs which have had the procedure. However, more data needs to be collected prior to the wholesale use or recommendation of any of these procedures.