Why aren’t all braces the same?
How important, in scoliosis treatment, is the type of therapeutic instrument used? Obviously, both the treatment itself and the instrument chosen are very important factors. After all, while it is true that one brace may not be as good as another, it is also true that even an excellent one must be managed through an adequate therapeutic approach, which determines how, and how much, it should be worn.
Obviously, the physician plays a key role in mediating this relationship, but the tolerability of the brace and the patient’s acceptance of it are fundamental elements, too. All these factors combined can increase the final effectiveness of the therapy.
Let’s examine this one step at time. First of all, what is scoliosis?
Adolescent idiopathic scoliosis (AIS) is a three-dimensional deformity of the spine and trunk. Even though it is a fairly common disorder, affecting about 1–3% of the population, only about 10% of diagnosed cases require treatment, and only 0.1–0.3% require surgery. The most important parameter when deciding on the type of treatment is the Cobb angle, which is measured on an upright full-spine radiograph. The therapeutic approaches to scoliosis range from observation alone to specific exercises, bracing and, in the most serious cases, surgery.
Bracing is an effective method of treating scoliosis, used for moderate and severe curves or when a patient refuses surgical treatment.
What exactly is a brace (the therapeutic instrument)?
A brace is a device (technically an orthosis) that applies external corrective forces to the trunk in order to correct the deformity.
According to guidelines published by SOSORT (International Society on Scoliosis Orthopaedic and Rehabilitation Treatment) in 2016, the aims of bracing as a treatment for scoliosis are to stop the disease from progressing during puberty, improve the patient’s appearance, prevent or treat pain, and prevent or treat respiratory dysfunctions.
How is a brace made?
Brace construction techniques have evolved over the years, but the objectives remain the same: to obtain maximum reduction of the curve through a design that can be well tolerated.
The construction process begins with a plaster cast or a 3D optical scan if CAD/CAM technology is being used, or alternatively with trunk measurements and the use of theoretical reference models.
In traditional construction, a plaster cast of the patient’s body is made and then split open to be used as a “mould” serving to reproduce the patient’s trunk. The resulting replica of the trunk is then modified manually in order to produce a model of the “corrected” trunk on which to construct the brace. If, instead, CAD/CAM technology is being used, the image is captured by scanners and then modified using software. Once the replica has been modified, it is sent to a milling machine which finishes the corrected “positive” model.
From this point on, the procedure is the same for all techniques: a plastic sheet is heated and wrapped around the positive model. The thickness of the plastic used may differ (ranging from 2 to 5 mm), as may its stiffness. Even though they are all made using similar methods, there exist different types of brace and they don’t all work in the same way.
A classification of braces
Braces work in different ways because they apply different biomechanical principles. What is more, they are custom-built devices, and so each one is unique!
A classification was recently developed based on the mode of action of different braces. There exist the following types:
⁃ traction braces: for obtaining upward vertical elongation of the spine (e.g. the Milwaukee brace);
⁃ Three-point braces: these act at three points in two or three planes of space (Boston, Lyon, PASB, Sibilla braces);
⁃ postural braces: these have a three-dimensional action (Cheneau, RCS, ART braces);
⁃ hypercorrective nighttime braces: these are used only at night (Charleston, Providence braces);
⁃ braces that push in a down-up direction: these braces produce a three-dimensional elongation, which is obtained by pushing the spine in a down-up direction. The Sforzesco brace, developed at the Isico centre by Prof. Stefano Negrini, is an example of this type of brace;
⁃ elastic braces, like SpineCor, which are used to treat mild-moderate scoliosis (between 20° and 35°) and to delay the use of a rigid brace. SpineCor is a dynamic brace based on the principle of the corrective SpineCor movement; this movement is maintained over time by means of the elastic bands. Unlike a rigid brace, it is practically invisible under clothes, and permits all trunk movements. However, it is less effective than other treatments.
It is very difficult for doctors to assess and manage all these different bracing options, even if they are experts in this condition. To increase the quality of the intervention and enhance the outcome for the patient, the best thing is to work with few models and only a few orthopaedic workshops.
The fundamental importance of the therapeutic approach
Whatever type of brace the physician recommends, the management of the therapy is still the most important thing.
Prescriptive protocols envisage that treatment should be started with a very high dosage (21-23 hours of brace wearing per day), before gradually reducing this, in such a way as to allow the spine to grow, and the postural control system to adapt and get used to maintaining the correction imposed by the brace. This latter aspect is supported by specific exercises, which enhance the spine’s ability to maintain the correction.
Bracing is an effective therapy providing the brace is worn for the number of hours prescribed by the physician.
Until a few years ago, the only way of checking that patients were using their braces correctly was to rely on information provided by family members and the patients themselves at follow-up appointments. Nowadays, however, we can use heat sensors to obtain accurate assessments of compliance (i.e. to assess the extent to which the patient and his/her family have adhered to the prescribed treatment).
A well-constructed brace
According to the five rules set out by Prof. Sibilla in 1995, a brace will work well if it is properly prescribed, properly made, properly tested, properly worn, and accompanied by appropriate exercises.
We would add a further rule: brace treatment must be carefully monitored by a complete, expert and vigilant team of professionals.
A brace must be worn for the prescribed number of hours; for this to be possible, it must be tested by qualified medical staff who have the ability to make the small changes necessary to avoid any need to interrupt the treatment. Each patient and his/her family must then be followed up over time by a physician, physiotherapist and orthopaedic technician. Each of these professionals plays a crucially important role in helping patients to complete the course of treatment, minimising its impact on their daily lives.
The revolutionary SFORZESCO brace
The Sforzesco brace, named after the Medieval Sforza family to recall its links with the city of Milan where it was developed, was created in 2004 by Prof. Stefano Negrini, scientific director of Isico, and Gianfranco Marchini, an orthopaedic technician. Their aim? To find a solution, based on some of the characteristics of the Risser plaster cast and the Lyon, Sibilla and Milwaukee braces, that would make it possible for severe scoliosis patients to avoid having to wear a plaster brace. To correct the curve, it acts mainly by pushing the spine in a down-up direction.
It is an effective but also a readily acceptable brace, given its optimal wearability.
The Sforzesco is a “super-rigid brace”. It has an external envelope that reproduces the natural shape of the human body, and the corrective action of this brace is enhanced by the addition of several pushing pads (which exert a pushing action).
According to published scientific evidence (particularly that contained in the 2011 paper Brace technology thematic series – The Sforzesco and Sibilla braces, and the SPoRT Symmetric, Patient oriented, Rigid, Three-dimensional, active concept), the Sforzesco brace is more effective than the Lyon brace and as effective as the Risser cast in the presence of severe curves. It has also been found to be effective from an aesthetic point of view, helping to improve the appearance of affected patients. Its action is different from that of other brace types, being based on traction, posture, three-point correction and movement-based correction. It was in fact created according to the SPoRT (Symmetric, Patient-oriented, Rigid, Three-dimensional, active) concept of bracing.
In the process of developing this new brace type, the concept of symmetry was gradually superseded. Nowadays the external envelope is no longer perfectly symmetrical, although it remains unobtrusive and therefore an aesthetically valid solution.
The fact that patients come to see it as an extension of themselves helps us to make this treatment more readily accepted by them; and ready acceptance translates into increased compliance and greater effectiveness. The material used and the type of construction confer high rigidity, which means more effective pushing compared with that provided by other brace types.
The Sforzesco brace has a three-dimensional action on the spine. It grants the four limbs total freedom of movement, and allows the patient maximum freedom in activities of daily living. The trunk moves inside the brace in accordance with the direction of the correction, while movements in the direction of progression of the deformity are completely prevented. This is why these brace types are defined active.
Whatever type of brace the physician recommends, the management of the therapy is still the most important thing.
From this point on, the procedure is the same for all techniques: a plastic sheet is heated and wrapped around the positive model. The thickness of the plastic used may differ (ranging from 2 to 5 mm), as may its stiffness. Even though they are all made using similar methods, there exist different types of brace and they don’t all work in the same way.
How important, in scoliosis treatment, is the type of therapeutic instrument used? Obviously, both the treatment itself and the instrument chosen are very important factors. After all, while it is true that one brace may not be as good as another, it is also true that even an excellent one must be managed through an adequate therapeutic approach, which determines how, and how much, it should be worn. Obviously, the physician plays a key role in mediating this relationship, but the tolerability of the brace and the patient’s acceptance of it are fundamental elements, too. All these factors combined can increase the final effectiveness of the therapy.
Whatever type of brace the physician recommends, the management of the therapy is still the most important thing.
Prescriptive protocols envisage that treatment should be started with a very high dosage (21-23 hours of brace wearing per day), before gradually reducing this, in such a way as to allow the spine to grow, and the postural control system to adapt and get used to maintaining the correction imposed by the brace. This latter aspect is supported by specific exercises, which enhance the spine’s ability to maintain the correction.