Physiotherapy Examination of a Joint
We thrive on participating in and completing many different activities which to a large extent depend on the condition of our body joints, from the large joints of locomotion (hips, knees) to the small joints such as the temporo-mandibular for speaking and eating. Our well-designed and durable joints do a very good job of allowing us to get about and involve ourselves in activity. Damage to our joints can be the result of disease, illness or trauma and this can restrict our mobility and reduce our functional capacity. Joint examination is a core ability of physiotherapists, consisting of a logical assessment, testing to find an abnormality and targeting of the treatment plan to these problems.
Joints, the junctions between two bones, can have weight carrying, force transmission or movement properties depending on their design and position in the body. An example of a movement joint is the shoulder with its great range, the acromio-clavicular joint is a force transmission joint allowing arm function and the back and hips are weight bearing joints with some movement function. The most obvious of our joints are all synovial joints, a particular and very important joint type. The bone ends are coated with articular cartilage which reduces friction, the joint fluid is secreted by the synovial joint lining membrane and the joint capsule, formed by the ligaments, holds the joint protected against mechanical forces.
After the visual examination the physiotherapist will palpate the joint and surrounding structures, which means exploring or stressing an area logically with the fingers or hand, an important physio skill to clarify the diagnosis. The physio will palpate around the joint margins, the joint line itself, the tendon insertions and the ligaments surrounding the joint. Effusion, which means the presence of synovial fluid in a joint, can be felt by the resistance it gives if it is tight, by its thickness and plasticity if it is sticky and by the way it can be moved around the joint if it watery.
Assessment of the active joint ranges of motion is routinely recorded by the physiotherapist, who also records why the joint range is not full and states the results in degrees or as a proportion of normal. The physio then tests the passive joint ranges, with the patient relaxing the joint, to see if there are restrictions or pain with this technique. If the patient cant move their joint through its full range but the physiotherapist can then muscular weakness or pain is the likely limiting reason. If the patients own movement is limited and the physio can get no more on testing, then stiffness of the joint and/or pain may be involved.
Passive testing of the joint ligaments is an important part of physiotherapy examination as the ligaments are integral to normal joint function. Ligaments should take the full stress of a persons strength in most major joints without any pain or other problems. Systematically testing the ligaments can identify an injured, painful, stretched or absent ligamentous structure. Muscle testing is done using the Oxford scale of 0-5, taking into account that pain and anxiety may change the muscular force a patient is able or willing to exert. Sensibility and joint position testing can be useful to see if the brain is receiving the correct feedback information it needs from the joint to plan effective and safe movement.
Ligaments are very important for normal function of a joint and the physiotherapist will routinely test their integrity, stressing them strongly by manual testing. The ligaments of major joints are very strong and testing a normal ligament should show no effect but it can uncover an absent, painful or stretched ligament by its effect on joint stability. Physios use the Oxford 0-5 scale to grade muscle strength, allowing for anxiety or pain which might interfere with a patients effort. Proprioception and joint sensibility may also be tested to ascertain if good feedback from the joint to the brain is present, this being important in normal movement planning.