Small fragments not amenable for fixation should be removed to avoid damaging the articular surface. In most cases, the hip joint luxates while the fragment remains attached to the ligament of the head of the femur.
After thorough exploration of the coxofemoral joint, small fragments not amenable for fixation are removed.
In most cases, joint stabilization will be required following fragment removal and reduction of the luxation. A capsulorrhaphy as well as a variety of other techniques can be performed to maintain reduction until the joint capsule heals. See other resources for surgical techniques for traumatic hip luxations.
Activity restriction is indicated until radiographs indicate bone healing of the fracture.
Phase 1: 1-3 day after surgery
Aim is to reduce the edema, inflammation and pain.
Integrative medical therapies, anti-inflammatory and analgesic medications.
Note: Nonsteroidal anti-inflammatory medications can be toxic in the cat and should only be used as labeled for the cat.
Phase 2: 4-10 days after surgery
Aim is to resolve the hematoma, edema and control pain, and prevent muscle contracture.
Anti-inflammatory (see nonsteroidal warning) and analgesic medications may still be needed. Rehabilitation and integrative medical therapies can be used.
Special attention should be given to patients less than 1 year of age with a femoral fracture. Rehabilitation is strongly recommended to help prevent quadriceps muscle contracture.
If the cat is not starting to use the limb within few days after surgery, a careful evaluation is recommended.
10-14 days after surgery the sutures are removed.
Radiographic assessment is performed every 4-8 weeks until bone healing is confirmed.
Robinson and Ehmer slings
After transecting the ligament of the femoral head for visualization, capsulorrhaphy is carefully performed for stability. Additional stabilization of the hip joint is sometimes required (see other resources for surgical techniques).
If after surgical treatment additional stability is required or the internal stabilization must be protected, a Robinson or an Ehmer sling may be applied.
The Robinson sling allows range of motion of the pelvic limb but prevents full weight bearing and full extension of the limb.
The Ehmer sling abducts and internally rotates the femoral head, preventing craniodorsal luxation.
These two slings must be carefully monitored after application to avoid complications such as skin irritation, abrasions, swelling of the foot, and slippage of the sling.
Further information on the correct application of these slings can be found in the literature.
Note: Some cats will not tolerate a sling and can cause self-harm when wearing one.
If there is no implant failure or infection, there is no need for implant removal.