What we treat - Preparing and Caring for Your Hip or Knee Joint Replacement Surgery

You and your doctor have decided that your hip or knee joint has deteriorated to the point where surgery, with all its associated risks, is a good treatment option for you.

Generally this means:

• Your joint pain is severe; and not well managed by medication or other conservative treatment measures
• Your mobility is seriously limited; there is major stiffness of the joint itself, but it also limits function, such as walking, stairs, getting up/down from sitting, etc, and
• There is X-ray evidence of advanced joint destruction.

The following is a video prepared by the American Academy of Orthopaedic Surgeons, AAOS. It covers the logistics of preparation for surgery really well.

The Physiotherapy contribution to your understanding of getting the best out of your new hip relates to muscle activity in the days and weeks immediately before and after surgery.

The reason why your muscles are so important is because they control much of the nerve information transiting from joints to the brain. Positional sensors are located within muscles (muscle spindles), where muscles transition into tendons to attach to bones (golgi tendon organs), and within joint capsules (low threshold mechanoreceptors). Working together, these positional sensors provide our sense of proprioception, also known as our sixth sense. It is this sense which informs our brains of where any joint is in space, whether our eyes are open or closed. A complete absence of proprioception renders us unstable and uncoordinated; and unable to rely on automatic reflexes, such as those we use to walk. It is unlikely that surgery itself would seriously disrupt proprioception; rather it is the disuse prior to surgery that may pose the greater risk.

How many times have you heard the phrase ‘use it or lose it’. Although it is used in many contexts, within the context of movement, it is particularly true. You have to use your muscles to trigger the sensory/motor nerve pathways. Our brains rely on the information from the muscle and joint sensors to define and produce motor function, or movement. Movement is required to trigger the positional sensors. Your ability to keep this system functioning will have a massive impact on post-surgical recovery.

A second consideration relating to the importance of sensory receptors, relates to your experience of pain. Sensory nerves also transmit the sensation of pain. Of significance with nerves is their size; the larger the nerve, the faster it conducts information. Bonus for those with pain, because the positional sensors activated by movement have larger nerves than do the nerves which transmit pain; and can minimize the pain messages being transmitted to the brain. While the relentlessness of severe pain makes using movement alone an inadequate pain management strategy. However, movement can dampen pain while you are moving, it may lessen the amount of pain medication you require. It is really important that you keep trying to use your muscles, even when it is painful.

The exercises that are likely to provide the most benefit as you prepare for surgery and the early days afterwards include:

1. Isometric exercise. Close your eyes and visualize as you contract your muscles in all movement directions for 10 seconds or more. No real movement occurs with these exercises; it is the intention to move that is important. Repeat 5 or 6 times in each direction. It is good to work the muscles on both the right and left sides of your body at the same time.
2. Range of motion exercise. Just as it sounds, move your joint(s) to the extent of possible range, as you bend, straighten your hips and knees, and as you move your hips out to the side. Move slowly and try to get to the edge of available range, but don’t add force to the movement. Before surgery and in the early days following surgery, force is not helpful.
3. Deep breathing exercises to maintain lung capacity and manage anxiety.
4. Supportive positioning and ankle pumping exercises are helpful to keep blood flowing in your legs and prevent deep vein thrombosis

While these are the basics of the exercises considered for all our clients, they don’t take into account individual needs. For example, many of our clients have muscle contractures that would mean exercises would be most effectively performed in a specific position. Likewise, extensor muscles are sometimes difficult to isolate and activate. All our clients need to progress through strengthening and conditioning activities, depending upon surgery-related restrictions and what their post surgical needs will be. For all of these reasons, whether for information only or for help throughout your rehab, we recommend you consult a physiotherapist.

Beyond exercise, some of our clients have more concerns than others with respect to their ability to be successful following joint replacement surgery. Some have underlying conditions, like diabetes, which can impair their ability to heal. Others have prior experience with infections, poor healing, etc. Still others have had their surgery, and know that their post-surgical recovery is delayed. We can help with many of these issues. Our low intensity laser provides injured tissues with additional ATP, which is cell fuel, for the purpose of kick-starting or accelerating normal healing. While it is clearly useful when delayed healing is identified, it can also be used before surgery to decrease the requirement for pain medication and to minimize the risk of post-surgical complications.