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Sharp pain is usually described in terms of a dichotomy with blunt or dull pain i.e. patients often describe their pain as either sharp, knifing, intense etc… or ….. dull, background ache, vague, consistent.
Sharp pain reflects the activation of a particular type of nerve ending and nerve pathway that delivers danger messages to the spinal cord and brain very rapidly. These nerve endings are activated by sudden changes in the local environment e.g. if the nerve ending is plugged into muscle tissue and that muscle tissue is suddenly stretched very powerfully and rapidly, you may experience a sensation of sharp pain. i.e. when the muscle fibres are rapidly stretched, the nerve ending receptors will be activated, and send a message up to your brain… your brain will tend to interpret very large and sudden mechanical changes in a muscle as a sign that something bad (i.e. a tear) may be happening. So the (very quick, reflex like) response is the generation of pain to warn you about the possibility of a problem occurring down in the calf muscle.
Generally, sharp pain is intense but short lasting… it’s there with a certain body position and then gone in another position. I think it helps to think of this type of pain as a sign that something unusual is happening in your body somewhere. It doesn’t necessarily point to the presence of injury, but likely indicates a regional area of increased sensitivity of these high speed nerve pathways.
Short lasting sharp pain in isolation is probably nothing to worry too much about, unless it becomes a repetitive pattern, or progresses to a more persistent pain over a number of days or weeks. What we see most commonly, is that sharp pain tends to occur over and above a background of dull ache.
When you injure a joint, or muscle or any body tissue really, there will be some localised bleeding in and around the injury site. When this happens, there is a mingling of certain cell types and chemicals that usually do not come into contact with each other. The mingling of these cells and chemicals kick starts a series of chemical reactions that promotes what is known as the inflammatory response. We don’t need to delve deeply into the various inflammatory mechanisms that are at play… except to say that the purpose of the inflammatory response, is to attract a bunch of chemicals from the blood stream to the injury site, so that the process of healing can begin.
It is the onset of inflammation that usually coincides with the onset of that characteristic deeper,dull, achy pain that you usually become aware of a few hours or perhaps the morning after after an injury. Unlike the “sharp” pain derived from the mechanosensitive nerve ending receptors, the achy quality of pain is derived from chemosensitive nerve ending receptors. Chemosensitive receptors are sensitive to the chemical environment into which the nerve ending is plugged. So we expect that there will be lots of inflammatory chemicals floating about, and we expect that these chemicals will trigger the activation of chemosensitive nerve endings. As more inflammatory chemicals migrate to the injured area from the bloodstream, more and more of the chemosensitive nerve endings will be triggered. Your brain will tend to interpret large changes in activity of these chemosensitive nerve endings as a sign that something bad (i.e. an injury or infection) may be happening. One of the responses is the generation of pain to warn you about the possibility of an ongoing problem occurring down in the calf muscle.
Taken together, we characteristically see sharp pain as a quick warning shot that something might be wrong, and then a subsequent dull ache as a sign that your body is attempting to deal with an injury or infection. Of course, once your system has switched to this more heightened state of sensitivity, movement that would not normally trigger “sharp pain” can begin to do so. That’s why we often feel sharp pain super imposed on a dull background ache with attempts to for example, aback pain patient to rise to standing after prolonged sitting, or attempts by someone who has sprained their ankle to weight-bear or walk.
A sense of stiffness or tightness in a joint or body part is most likely a product of your body protecting a current or old injury. If it is a current injury, it is useful for your body to guard the injured area by increasing your muscle tension to brace the injured tissues. A recent injury is also likely to be associated with swelling which will also add to the sense of stiffness and tightness.
If it is an old injury however, the value of that protective bracing is likely quite low, and is probably more of hindrance than anything else. For people who haven’t recently been injured, a sense of stiffness and tightness probably reflects an accumulative ramping up of motor output in response to heightened sensitivity of the nerve endings in the affected body region. This can become a bit of a catch 22 as the altered, or ramped motor output can create its own issues in terms of blood flow to neural tissue, which may further heighten nerve ending sensitivity, and create more defensive motor output.
For people dealing with stiffness and tightness in the absence of pain, some sort of manual therapy intervention is highly recommended. it makes way more sense to address these symptoms before they progress to the point of pain or other symptoms such as pins and needles or numbness.
Pins and needles or numbness reflect some sort of disturbance to either nerve pathways or the flow of blood within your arteries or veins. In terms of blood vessels, the disturbance is usually mechanical (as opposed to inflammatory). There are some clues that raise the index of suspicion for a vascular rather than neural origin, but those types of clinical decisions fall more into the scope of a GP or doctor than they do a physio.
From a physio point of view, the presence of pins and needles or numbness in association with particular distributions of pain helps us to arrive at a provisional diagnosis and tentative judgment about the severity of a given condition. For example, a patient with a complaint of complete numbness in both legs would prompt a far different treatment response than a patient with numbness in a specific dermatome. Many degenerative neurological conditions begin with subtle sensory disturbances such as pins and needles or numbness.
Generally, if you been experiencing unusual pins and needles or numbness for more than a few days, it is a good idea to get it checked out by your GP or physio.
It makes sense to think of a sense of weakness as arising because your central nervous system and brain make a judgment that it is in your body’s best interest to not load a particular joint or body part beyond a particular threshold. This judgment might be quite accurate or not. In the case of a torn calf muscle for example, any attempt to walk on the leg will (apart from being painful) be really weak i.e. your body simply shuts off motor output to the region. The common scenario though, is a sense of a subtle drop in power or ability to use a body part with the same degree of force and coordination as compared to the opposite arm / leg, or as compared to a previous timeframe. All this could be as simple as a defensive motor output that is no longer serving you any purpose. On the other hand, some changes to motor control or power can be indicative of the onset of more serious neurological condition.
Generally, if you been experiencing unusual weakness for more than a few weeks, it is a good idea to get it checked out by your GP or physio.
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