Orthopedic exam and bandaging (Proceedings)
Use a systematic approach to ensure that you do not miss any problems. In general I use an eight step approach to the orthopedic examination:
1) Signalment – age, gender, breed. This information can help you narrow your differential diagnosis list, by excluding certain diagnosis that only occur in animals of a certain age range or breed. It should also help you to weight certain diagnoses, moving them higher or lower on your list of differentials.
2) History – includes when problem started, owner identification of involved limb, problem progression (is it getting worse, better or staying the same over time), efficacy of previous and/or current treatments, variations in the problem (lameness) and presence of any systemic illness. A problem like osteoarthritis is usually worse when the animal first arises and then improves with moderate activity. With a muscle, tendon or ligament problem, the animal is usually fine at the beginning of an activity and becomes progressively more lame and may eventually just quit.Also be attuned to unusual presentations, such as the older animal that suddenly becomes non-weight bearing while walking or going down stairs. If a fracture is found, be suspicious of a pathological process, i.e. osteosarcoma, causing the fracture. A chronic disease such as coxofemoral osteoarthritis secondary to canine hip dysplasia or patellar luxation does not cause an acute non-weight bearing lameness. Think about other causes of the lameness such as an acute hip luxation, a fracture or a cranial cruciate ligament rupture.
Also, orthopedic problems will almost never cause an animal to drag its toes and cause nail wear. If you hear about this, be thinking about a neurological problem. Don't ignore other limbs just because you've been told that the presenting complaint is in a specific limb. For example, I recently saw a puppy that was brought in for a right thoracic limb problem and the dog indeed had a growth abnormality in the right antebrachium. But the dog was limping off of the left thoracic limb and I diagnosed a left fragmented coronoid process!
3) Gait Evaluation – Look at how the animal stands, sits, and rises. Look for general conformation, limb symmetry, joint alignment, weight shifting. A dog with cranial cruciate ligament disease will not sit with the affected limb flexed beneath it (positive sit test).
First the gait at a walk, looking for shortened stride length, abnormal joint movement, head bobbing, shifting of body weight and ataxia or nail scuffing. Head bobs occur with thoracic limb problems and the dog's head will go down when weight is placed on the sound limb and come back up when weight is placed on the lame limb as the dog tries to decrease the weight born on the affected leg. A swinging, circumduction of the thoracic limb is associated with infraspinatus tendon contracture. A dog with palmar laxity or carpal hyperextension injury will stand and walk with the more than normal extension in the radiocarpal joint (palmigrade).
If a joint is painful for the dog, they will usually limit the range of motion of that joint during the gait cycle. A dog with hip dysplasia or secondary arthritis is painful during hip extension and will not fully extend its legs even at faster gaits. It is painful for a dog with cranial cruiate ligament disease to flex its affected stifle and will keep it's stifle somewhat extended during the gait cycle. A dog with patellar luxation is not usually lame until the patella luxates at which time it will kick or extend its leg behind itself until the patella is reduced.
4) Standing examination – Lameness is usually present because the animal is painful somewhere. Unfortunately in order to localize the problem/source of pain, we have to inflict pain. Most dogs will vocalize or try to pull away when you get to a painful spot, but they may try to bite. Once you know an area is painful, be gentle during further assessment. I also try to start with the normal, non-painful limbs so the animal is not expecting to be hurt every time you touch it.
Usually start with a brief, screening neurologic exam, palpating along the spine, moving the neck and lifting the tail. Check for conscious proprioceptive deficits if nail scuffing or wear seen during gait evaluation. Palpate both thoracic limbs, then both pelvic limbs simultaneously to compare muscle mass, joint distension, abnormal posture/conformation. It is easier to appreciate mild muscle loss or joint effusion when the other side is normal. You can often see joint effusion in the hock of dogs with an OCD lesion by looking and palpating from behind. A dog with a chronic cruciate ligament rupture will have thickened soft tissue on the medial aspect of the stifle, called a medial buttress, that can be felt and seen during the standing exam.
I will usually lift and palpate each limb individually wil the dog is standing. The dog may be unwilling or unable to support weight on the problem limb. I also check for cranial tibial thrust with a tibial compression test while the dog is standing.