Blocking Newly Identified Molecule May Improve And Speed Recovery From Stroke

Blocking Newly Identified Molecule May Improve And Speed Recovery From Stroke

Researchers at UCLA have identified a novel molecule in the brain that, after stroke, blocks the formation of new connections between neurons. As a result, it limits the brain's recovery. In a mouse model, the researchers showed that blocking this molecule - called ephrin-A5 - induces axonal sprouting, that is, the growth of new connections between the brain's neurons, or cells, and as a result promotes functional recovery.

If duplicated in humans, the identification of this molecule could pave the way for a more rapid recovery from stroke and may allow a synergy with existing treatments, such as physical therapy.

Stroke is the leading cause of adult disability because of the brain's limited capacity for repair. An important process in recovery after stroke may be in the formation of new connections, termed axonal sprouting. The adult brain inhibits axonal sprouting and the formation of these connections. In previous work the researchers found, paradoxically, that the brain sends mixed signals after a stroke - activating molecules that both stimulate and inhibit axonal sprouting. In this present work, the researchers have identified the effect of one molecule that inhibits axonal sprouting and determined the new connections in the brain that are necessary to form for recovery.

The researchers also developed a new tissue bioengineering approach for delivering drugs to the brain after stroke. This approach uses a biopolymer hydrogel, or a gel of naturally occurring brain proteins, to release neural repair molecules directly to the target region for recovery in stroke - the tissue adjacent to the center of the stroke.

Last, the paper also shows that the more behavioral activity after stroke, such as the amount an impaired limb is used, the more new connections are directly stimulated to form in the injured brain. This direct link between movement patterns, like those that occur in neurorehabilitation, and the formation of new brain connections, provides a biological mechanism for the effects of some forms of physical therapy after stroke.

Manual Physical Therapy for Pain Relief

Many patients arrive at their first physical therapy appointment expecting to receive hot packs, ultrasound and instructions on how to complete a series of exercises. These modalities are warranted in many instances and most therapists would agree that exercise is needed to help restore muscle imbalances. However, many therapists now approach the restoration of function from a different perspective. These therapists are interested in why a muscle isn’t functioning properly and view back exercise not as the driving mode of recovery but as a complement to manual therapy. They may, for instance, look to restore proper sacroiliac or lumbar joint function to treat piriformis syndrome rather then directly manipulate the piriformis muscle through exercise.

Manual physical therapy is a specialized form of physical therapy delivered with the hands as opposed to a device or machine. In manual therapy, practitioners use their hands to put pressure on muscle tissue and manipulate joints in an attempt to decrease back pain caused by muscle spasm, muscle tension and joint dysfunction.

Manual Physical Therapy can Offer Pain Relief for Acute and Chronic Back Pain

Manual therapy can be helpful for the treatment of joints that lack adequate mobility and range of motion in certain musculo-skeletal conditions. This limitation can cause discomfort, pain, and an alteration in function, posture, and movement. Manual physical therapy involves restoring mobility to stiff joints and reducing muscle tension in order to return the patient to more natural movement without pain. Thus, manual physical therapy may provide back pain relief both for patients with chronic back pain involving joint problems, such as sacroiliac joint dysfunction , and acute back pain from soft tissue injuries such as a back muscle strain or a pulled back ligament. Although extensive clinical studies have yet to be performed on all areas of manual therapy, limited clinical data and patient reports support the assertion that manual physical therapy can be effective in relieving back pain for certain patients.

As a group, manual physical therapy techniques are aimed at relaxing tense back muscles and restricted joints in order to decrease back pain and increase flexibility. In general, manual physical therapy techniques employ the following types of movement:

•    Soft tissue work, including massage, which applies pressure to the soft tissues of the body such as the muscles. This pressure can help relax muscles, increase circulation, break up scar tissue, and ease pain in the soft tissues.

•    Mobilization/manipulation, which uses measured movements of varying speed (slow to fast), force (gentle to forceful), and distances (called ‘amplitude’) to twist, pull, or push bones and joints into position. This can help loosen tight tissues around a joint, reduce pain in a joint and surrounding tissue, and help with flexibility and alignment.

The following page covers the specific manual physical therapy techniques that are designed to alleviate low back pain related to muscle spasm, muscle tension and joint problems.

Therapeutic Ultrasound In Physical Therapy

THERAPEUTIC ULTRASOUND IN PHYSICAL THERAPY

Ultrasound is a therapeutic modality that has been used by physical therapists since the 1940s. Ultrasound is applied using a round-headed wand or probe that is put in direct contact with the patient's skin. Ultrasound gel is used on all surfaces of the head in order to reduce friction and assist in the transmission of the ultrasonic waves. Therapeutic ultrasound is in the frequency range of about 0.8-3.0 MHz.

The waves are generated by a piezoelectric effect caused by the vibration of crystals within the head of the wand/probe. The sound waves that pass through the skin cause a vibration of the local tissues. This vibration or cavitation can cause a deep heating locally though usually no sensation of heat will be felt by the patient. In situations where a heating effect is not desirable, such as a fresh injury with acute inflammation, the ultrasound can be pulsed rather than continuously transmitted.

Ultrasound can produce many effects other than just the potential heating effect. It has been shown to cause increases in tissue relaxation, local blood flow, and scar tissue breakdown. The effect of the increase in local blood flow can be used to help reduce local swelling and chronic inflammation, and, according to some studies, promote bone fracture healing. The intensity or power density of the ultrasound can be adjusted depending on the desired effect. A greater power density (measured in watt/cm² is often used in cases where scar tissue breakdown is the goal.

Ultrasound can also be used to achieve phonophoresis. This is a non-invasive way of administering medications to tissues below the skin; perfect for patients who are uncomfortable with injections. With this technique, the ultrasonic energy forces the medication through the skin. Cortisone, used to reduce inflammation, is one of the more commonly used substances delivered in this way.

A typical ultrasound treatment will take from 3-5 minutes depending on the size of the area being treated. In cases where scar tissue breakdown is the goal, this treatment time can be much longer. During the treatment the head of the ultrasound probe is kept in constant motion. If kept in constant motion, the patient should feel no discomfort at all. If the probe is held in one place for more than just a few seconds, a build up of the sound energy can result which can become uncomfortable. Interestingly, if there is even a very minor break in a bone in the area that is close to the surface, a sharp pain may be felt. This occurs as the sound waves get trapped between the two parts of the break and build up until becoming painful. In this way ultrasound can often be used as a fairly accurate tool for diagnosing minor fractures that may not be obvious on x-ray.

Some conditions treated with ultrasound include tendonitis (or tendinitis if you prefer), non-acute joint swelling, muscle spasm, and even Peyronie's Disease (to break down the scar tissue). Contraindications of ultrasound include local malignancy, metal implants below the area being treated, local acute infection, vascular abnormalities, and directly on the abdomen of pregnant women. It is also contraindicated to apply ultrasound directly over active epiphyseal regions (growth plates) in children, over the spinal cord in the area of a laminectomy, or over the eyes, skull, or testes.