Physical rehabilitation: Improving the outcome in dogs with orthopedic problems
Advances in small-animal medicine and surgery have led to an improved and sophisticated level of healthcare for pets. Patients with problems that were once considered untreatable can now be evaluated by specialists in a variety of disciplines. For example, in patients with orthopedic problems, diagnostic and treatment options have widely expanded. Orthopedic surgery is unique in that the corrective procedure is completed rapidly relative to the patient's recovery. After an orthopedic procedure, it is common to have a convalescent period of weeks to months before recovery is attained. Physical rehabilitation may help patients achieve maximum recovery. Physical therapy is also valuable for easing chronic pain in pets.
Physical therapy has become more common is small-animal patients, in part, because of its benefits in people. Clients are aware of these benefits because of the importance and ubiquity of physical therapy in human medicine. Many protocols in human physical therapy have been developed by using animal models. Likewise, techniques used in human physical therapy are being adapted for use in small and large animals. As information concerning physical rehabilitation increases in the veterinary literature, additional techniques will be incorporated in veterinary practices to improve the standard of care.
In this article, we introduce a variety of physical rehabilitation modalities available to small-animal practitioners, including their most common indications and their benefits. The benefits of physical rehabilitation are multifaceted, and some may not be intuitive. Depending on the modality used, benefits include pain relief, decreased inflammation and swelling, increased tissue extensibility and flexibility, strengthening, improved balance and proprioception, mobilization of tissues, improved limb and joint biomechanics, improved weightbearing, psychological benefits, weight loss, and improved cardiovascular and respiratory fitness.1-4POSTOPERATIVE REHABILITATION
Postoperative rehabilitation begins with aggressive analgesia before anesthetic recovery to reduce peripheral and central nervous system sensitization to pain.5-9 Since pain is one of the primary factors limiting mobility, it is paramount that it be eliminated or minimized. Optimal pain relief encourages early mobilization of an affected limb. Untreated pain leads to an increased metabolic rate, cardiovascular stress, impaired immunity, central and peripheral hyperalgesia, pulmonary dysfunction, and guarding of the limb with the joints in a flexed position, a condition referred to as reflex inhibition.8,10
Nonsteroidal anti-inflammatory drugs (NSAIDs) that spare the cyclooxygenase-1 (COX-1) enzyme but inhibit the cyclooxygenase-2 (COX-2) enzyme, such as deracoxib and carprofen, significantly reduce the production of prostaglandins and inflammation associated with injury or surgical trauma.6 Other NSAIDs, such as tepoxalin, etodolac, and meloxicam, are also good anti-inflammatory agents but are not approved for administration before surgery in dogs. They may be given postoperatively if there is no danger of continued hemorrhage or to manage chronic pain. However, different NSAIDs should be not be given concurrently, and an appropriate washout period is necessary when changing NSAIDs. Avoid drugs that selectively inhibit the COX-1 enzyme, such as aspirin, in the perioperative period because they can inhibit platelet function and contribute to intraoperative hemorrhage.11,12
Other medications that may be used alone or in combination with NSAIDs for analgesia in dogs include acetaminophen, codeine (either alone or in combination with acetaminophen), and tramadol. An opioid narcotic, such as buprenorphine, morphine, hydromorphone, or oxymorphone, should also be used to provide multimodal analgesia, which is more effective for pain control than a single agent used alone.13 Ketamine blocks N-methyl-D-aspartate (NMDA) receptors that are at least partly responsible for the wind-up effect of an uncontrolled pain stimulus and may be combined with NSAIDs and opioid drugs in the immediate postoperative period for additional analgesia.7,14,15 Lidocaine may be used as a constant-rate infusion to decrease the amount of narcotics needed for pain control.14 Lidocaine can be combined with ketamine or an opioid, such as fentanyl or morphine, and be given as a constant-rate infusion after trauma, intraoperatively, or postoperatively to combat pain. Epidurals and regional and local nerve blocks should be used when appropriate to further alleviate pain. Intra-articular injections of bupivacaine or lidocaine administered before surgery and again at the end of surgery also provide analgesia.16