The thought of Functional Fracture Healing

The conventional above the knees Plaster of Paris casts didn’t allow the movement of the knee joint. In 1963, as a leading external fixator manufacturer and orthopedic implant company, we saw the development of PTB cast and the creation of the below-knee cast, which could be used for the treatment of fractures of the tibia as well as permitted the mobilization of the knee joint. This doawn the knee cast, which was designed on the lines of patellar tendon-bearing (PTB) prosthesis (used by knee amputees), soon came to be known as the PTB cast. 

At that time, we did not realize the impact of this shift from conventional treatments of tibial fractures, on general people’s thinking about fracture healing and fracture management. These preliminary and upcoming experiences have cast new light on our understanding of fracture behavior in different environments and the benefits of limb function, particularly related to the importance of motion between the fragments in fracture healing.

We don’t say that we are the first to acknowledge the osteogenic role of function in fracture healing. Over the years, many others have also (Cham Pionniere 1903; Bohler 1953; Perkins 1955; Dehne1961).

However, In present times, orthopedic surgeons are educated with the fact that fractures and limb immobilization is advantageous for fracture healing. This has been the existing and leading philosophy for many generations.

In the late 60s and 70s, the Swiss Society for the Study of osteosynthesis, popularly known as the AO society wholeheartedly supported and spread the treatment based on the belief that strict immobilization and inter-fragmentary compression was the most effective means to manage fractures (ALLGOWER 1965; MULLER et. at 1965). This treatment methodology has an enormous impact on the study of bone formation throughout the world. AO techniques are still well-liked, particularly in the management of tubular bones and intraarticular fractures.

There is no uncertainty in saying that over the years, this AO technology and planned approach to fracture management has played an impactful role in raising the standards of fracture treatment methodology. The contribution of AO to technology is simply unbelievable.

Although, the groundwork of this AO philosophy proved to be flawed as neither firm fixation of fractures or compression in fragments have been demonstrated to be helpful to fracture healing. On the opposite, they hold back the healing of the fracture.

When it was first understood that a distal shaft fracture of the tibia could be treated successfully with a cast mold (like the PTB prosthesis) and a Grace that freed both the knee and ankle joints, it became obvious that the traditional concept of immobilization of joints above and below fractures as an essential for fracture healing was flawed. It then became obvious that fracture bracing instead of being just a technique, was an important part of the fracture healing cycle.

Functional fracture bracing confronts the concept that physical movement reduction and rigid fixation of fractures encourages bone formation. Fracture bracing is based on the fact that bone fragment contact (end-to-end or other) is not required to obtain bone amalgamation and that rigid immobilization of fracture fragments and halt of joint movements above and below the fracture are harmful to fracture healing.

In our 3 decades of orthopedic surgical implants manufacture and external fixator distributor business, we are convinced of the notion that the motion between the fragments due to any kind of functional activity augments osteogenesis. This motion is the primary factor for bone formation.
Motion between fragments is also likely to be responsible for the massive influx of capillaries into the fracture site, although their role in bone formation and fragment motion and the production of growth factors is yet to be discovered.

The peripheral lump that typically separates the fracture site in functionally treated diaphyseal fractures (with cysts, braces, or intramedullary nails) represents a type of unification that is instinctively superior to the one obtained in the presence of rigidly immobilized fragments. This peripheral lump or callus provides stiffness and strength to the limb in various stages of healing.

The fact that joints and muscles may be completely working after a rigid internal fixation does not cover the fact that it is a type of healing that has inferior mechanical properties or the demineralization of the bone underneath the fixation device. On the contrary, the peripheral callus that forms at the fracture site following intramedullary (inside the bone) fixation is likely to be the result of the motion that takes place between the fragments.

Microscopic studies of cortical bone healing with movement strongly suggest that the bone in itself plays a quite minimal role in its self-healing process. The soft tissues in the proximity of the bony structure seem to be responsible for the reparative process primarily through a capillary invasion. (GOTHMAN 1961,1962; RHINELANDER 1962; HOLDEN 1972 MCKIBBEN 1978; SARMIENTO 1984b)
We accept the fact that there are many instances in clinical practice where the surgical treatment of fractures is preferred over closed treatment. This is generally seen when the realistic advantages of surgery overshadow the biological disadvantages of the intramedullary techniques, for example, the fractures of the femur.

Fracture bracing is not a universal remedy. The application of the technique must be followed by a clear understanding of its basics, limitations, indications, and side-effects. As per our experience, we believe that functional bracing has a major place and role in the cure of low energy diaphyseal fractures of the tibia, humerus, and ulna. Its benefits are restricted in the case of open fractures which are the results of high-energy injuries as well as in high-energy fractures of both bones of the forearm or in severely minute fractures of the distal radius.

In this case study, we have worked to present clinical and laboratory information about the fracture healing cycle in a functional environment and guided the reader step by step, through the bracing techniques and its importance in various fractures and their treatment.

Over the years, understanding of functional bracing the indications for its use have Changed In some instances we have reduced its indications when we recognized the advantages of newly developed surgical techniques. In other areas, however, we have expanded its indication

Throughout this text and as our experience as an orthopedic surgical instruments company, we have tried our best to discuss the indications and contraindications and tried to present corresponding examples of fractures treated with braces. Statistical data are also provided as available.