We call biomechanical study to the complementary test that podiatrists perform to evaluate the correct muscular, nervous, articular functioning and the harmony of the whole to perform a process of movement of the human being.
In this sense, we can make several classifications according to the sense of its execution and, therefore, we have:
- Biomechanical studies with diagnostic orientation: they are performed as a complement to the anamnesis and help us to weigh the correct diagnosis of the semiological picture that the patient presents before other differential diagnoses.
- Biomechanical studies with orthopedic orientation: they are usually the most frequent and their purpose is to highlight those alterations of the locomotor apparatus or posture, to be subsequently treated by different types of orthopedic devices such as foot and ankle orthoses, prostheses, etc., as well as proprioceptive or postural rehabilitation measures. It should be routinely performed in infants at 4, 6 and 8 years of age to evaluate the correct growth of the locomotor apparatus.
- Biomechanical studies for the sporting gesture: where we focus on the analysis of the movement during the practice of the sport. For example, we perform a detailed analysis of the running technique of a long-distance runner, which can be modified to find a more efficient gesture to improve performance and on the decrease in the appearance of different pathologies related to poor sports technique.
- Biomechanical studies with surgical orientation: since it is a critical factor in pre-surgical decisions, it is important to know the real state during the movement of the segments, joints and musculature that we are going to intervene. For example, in a patient who is going to undergo Hallux Valgus (bunions) correction, we will take into account not only the levels of disorder of the angles of the bones between them, but also whether there are compensations in the gait caused by this pathology in order to know whether to compensate them in the same surgical act.
What aspects does it analyze and what information will it offer?
It analyzes several points that should be highlighted:
- Standing statics: from a standing position we evaluate the different positions of certain anatomical points of the patient, comparing them with each other and showing, for example, differences in length of the lower limb, spine curvatures, hip rotations, etc. The anteroposterior inclinations of the body can also be seen, since a person can be “forward” or “backward” due to muscular, fascial or balance alterations.
- Static in seated position: in this part of the examination we perform a muscle balance and joint range of the different joints of the foot and leg. Also, we see if there are bone torsions, or instabilities of the knee and ankle ligaments.
- Dynamics: in corridor or treadmill, we perform a visual study, computer-assisted or not, depending on the levels of need of the patient, where we can observe the harmony in which the step or gait cycle is developed, highlighting positions, angles or movements that are out of the standardized pattern. This point is of vital importance in the analysis of the sport gesture.
- Stabilometry or Baropodometry: through a platform of pressures and balance, we perform an analysis of the way in which the foot supports, both in the pressure points, which may be more marked in certain areas, thus presenting overload injuries, or in diabetics ulcers or pre-ulcerous lesions. The analysis of balance provides us with data on the stability and posture of the patient by analyzing the center of mass or central point of balance.
Through all these measurements and, together with the patient’s anamnesis, the biomechanical analysis provides a more accurate approach to the diagnosis of the patient’s pathology. The usefulness lies in the fact that this type of analysis is highly specific and allows us to be very certain as to what specific problem the patient presents. For example, to say that a patient suffers from excessive pronation is quite unspecific and, through biomechanical analysis, we can discern what specific reason is responsible for the pronation. For example, due to a weakness due to plastic deformity of the posterior tibial.
It should also be noted that these tests are not per group, nor do they all have to be performed necessarily, they are only diagnostic tools that we use to reach the correct diagnosis. We proceed to ask for tests as needed, these biomechanical analysis are the same and if with certain means we have been able to clarify the correct diagnosis we do not have to necessarily pass the patient through the entire exploratory cycle.
Why is it important to perform a biomechanical study?
The importance of the biomechanical study is its diagnostic purpose. Therefore, we recommend that patients in the following cases undergo biomechanical studies:
- Children at 4, 6, 8 and 12 years of age: routinely to determine if they are developing correctly.
- Patients who have discomfort when walking: regardless of their age.
- Diabetics as part of their annual check-up: since we can anticipate the deformities that this group of patients present as a result of their disease. One of the classic diabetic deformities is Charcot foot, which can be more easily controlled if orthopedic compensatory measures are established during its development. Hence the importance of its revision for possible treatment.
- Athletes who want to improve their technique or sporting gesture: avoiding injuries and improving their performance.
How is it different from a gait analysis?
As we have commented previously, the biomechanical analysis does not depend only on the visualization of the gait pattern, since this is a part of the biomechanical analysis, to specify the difference is that the gait analysis is a part of the biomechanical analysis and a biomechanical analysis cannot be performed only through the observation of the gait, since the clinical interview or anamnesis is the most important part and from which the request and performance of other tests directly depend.