Pseudarthrosis. When a bone fracture does not have the expected consolidation.
DATE: 28 January 2022
What are bone fractures? It’s fundamental to firstly understand this point to finally define what Pseudarthrosis is and when this kind of orthopaedic issue may occur. More in-depth, we’ll know bone fractures’ clinic progression. Usually, a patient needs a well thought multidisciplinary therapeutic schedule, a long time and a lot of rehabilitation to heal from a bone fracture.
After a complex fracture, the first medical treatment is surgery. An orthopaedic surgeon’s goal is a proper alignment of fractured bone segments, sometimes by screws, plates or intramedullary nails and by stabilization through plaster cast or brace.
Moreover, surgery has the purpose of recovering the proper bone “anatomy” and the blood supply; in fact, the bloodstream allows the correct oxygenation of damaged tissue and the intake of nutritional substances, which are both fundamental for the right and fast consolidation of the bone fracture.
If the healing proceeds properly, after a couple of weeks, a callus is formed between the bone segments: it’s a solid and physiologic scar that allows bone consolidation and calcification and the recovery of all bone functions and characteristics.
Thanks to advanced surgical techniques, constant medical evaluations and all support therapies, it’s possible to have effective and complete healing in 99 fractures over 100.
It’s just in that 1% of cases that the pathologic complication called Pseudarthrosis - that we’ll analyse in this article - may occur.
Pseudarthrosis. Numbers in Italy.
230.000 per year: this is the yearly average number of bone fractures due to the so-called fragility conditions (osteoporosis, senility, ect.). This figure becomes significant if compared to a population of 60 million people on average.
Moreover, including other types of fractures, such as post-traumatic ones (due to car, work or sport accidents), 1% of fractures that may become Pseudarthrosis is remarkable and big data.
Ultimately, fractures and Pseudarthrosis represent a common issue that requires an orthopaedic surgeon consultancy.
Like the majority of medical words and definitions, Pseudarthrosis has a Greek origin. It’s composed of “pseudo” (false) and “arthro” (articulation) in addition, the suffix “-osi” indicates a degenerative and pathologic process. For this, Pseudarthrosis means “degeneration of false articulation”.
Today, Pseudarthrosis is clinically defined as the non-consolidation of a fracture after at least six months from the traumatic event that caused it. Pseudarthrosis is, therefore, a late, not acute bone fracture complication.
May pseudarthrosis occur in all bones?
Pseudarthrosis is more common in those segments with more weakened vascularization (i.e., peripheric segments - epiphysis- of long bones like femur and tibia). Pseudarthrosis risk also depends on anatomical factors and, not least, on fracture severity (comminuted, compound or displaced fracture). This directly affects vascularization, oxygen and nutrients apport, infection risk and damaged tissue amount. At last, Pseudarthrosis may occur in every segment of a fractured bone, also with different characteristics:
These are the most common Pseudarthrosis.
Which is the cause of Pseudarthrosis?
As said above, the two most relevant causes of Pseudarthrosis are an improper alignment of bone segments and/or an insufficient blood supply. It is due to massive damage of internal blood vessels of the bone (the so-called Havers and Volkmann canals) that sprinkle all bone cells. In addition, infections may have a key role in Pseudarthrosis development, that are common after compound and exposed fractures.
Do risk factors exist for Pseudarthrosis evolution?
Risk factors are all those habits or conditions that affect oxygenation (i.e., tobacco smoke or anaemia). Furthermore, some chronic pathologies like diabetes, excessive use of corticosteroids drugs, old age, an insufficient supply of nutrients, proteins, trace elements, calcium or vitamins (especially vitamin C and D) are all factors that may promote pseudoarthrosis development.
Which are Pseudarthrosis consequences?
The main issue for patients is of a clinical and functional kind. Painful symptoms are often present and may manifest in the static stage (immobilized and no weight-bearing) or just in the dynamic stage. Moreover, Pseudarthrosis may lead to invalidating and severe conditions, with significant functional limitations right up to the impossibility of moving the limb or weight-bearing.
HOW TO TREAT PSEUDARTHROSIS?
Like other diseases, to establish the right treatment plan, the most important factors are the clinical picture severity, the involved bone segment and the patient’s general medical conditions.
Furthermore, its natural derivation allows a significant reduction in costs compared to other synthetic bone substitutes and the possibility of using it also for large portions of missing bone.
Firstly, it’s significant to manage and limit all risk factors, secondly to know all the comorbidities and chronic pathologies, like diabetes.
Pseudarthrosis specific treatments also include, in this case, both surgical and medical approach.
Among non-surgical treatments (non-invasive), there are Pulsed electromagnetic field therapy (PEMFT, or PEMF therapy) and extracorporeal shockwave therapy. Both therapies are provided using electromedical devices that bio-stimulate the bone thanks to different procedures.
On the other hand, surgical treatments include recovery of the bone segment in the event of simultaneous hyper infection, internal fixation (screws, plates and intramedullary nailing system) or external fixation, as circular Ilizarov fixation system.
Sometimes, it’s necessary to associate bone grafts or similar to osteosynthesis.
Autologous bone graft (autograft)
An autologous (autograft) bone substitute involves self-donation from the same patient, i.e., from the iliac crest. They are osteoconductive and osteoinductive. A bone graft provides a scaffold where a new bone can grow. This kind of graft provides bone cells and growth factors that stimulate bone regeneration. Despite an excellent quality, there are still several disadvantages to this methodology, starting from limited availability. It’s also challenging to obtain a sufficient quantity of bone graft when the substance loss is remarkable.
The bone material used comes from a living donor (usually from femoral heads) or cadaver collection. The main advantage is that the bone tissue is not taken from the patient itself, limiting incisions and post-surgery pain.
Also, this kind of graft can be a scaffold for the new bone tissue formation (osteoconductive property), but it does not contain live cells. In that case, it has to be replaced with the new patient’s bone (it doesn’t have osteoinductive properties).
They are synthetic materials that have a composition similar to the human bone. They have osteoconductive but not osteoinductive properties, like allograft. As for disadvantages, it’s relevant to say that they have high prices, lower mechanic properties and longer integration timing if compared with human bones.
Pseudarthrosis: GreenBone® solution
In the landscape of bone substitutes, Greenbone® represents a unique and highly innovative alternative. Indeed, it has a singular variety of properties: osteoconductivity, osseointegration and excellent biomechanical properties.
GreenBone® Bone Substitute is a synthetic, acellular, absorbable, new generation bone substitute. All these properties do so that it is ideal for surgical reconstruction of bone defects.
GreenBone® Bone Substitute originated from Rattan wood, is a biomimetic bone substitute designed to mimic the chemical composition (calcium phosphate phases plus ions) and porous architecture of natural bone and is suitable for the natural process of bone regeneration. Its 3d internal architecture allows the natural process of bone regeneration.
In conclusion, Pseudarthrosis is an uncommon issue, but this clinical condition can be treated and resolved using different orthopaedic solutions.
However, Greenbone's® innovative approach best combines all the basic therapeutic needs with simplicity and short ossification time.