From 5 to 10% of long bone fractures leads to delayed union. Non-unions can be radiographically classified into hypertrophic or atrophic.
Causes of nonunion
From 5 to 10% of long bone fractures leads to delayed union, which results in the loss of independence, the occurrence of concomitant diseases and significant absence from work. Non-unions can be radiographically classified into hypertrophic or atrophic. In the case of hypertrophic non-union, a significant amount of callus is created, which does not link bone fragments, while in the case of atrophic non-union a callus is not developed and a bone tissue is resorbed. The pathogenesis of non-union is multi-dimensional. The most frequently occurred causes can be divided into three main groups: external causes (trauma-related injuries) – these include: displacement of bone fragments, a significant level of damage of the surrounding soft tissues, activation of large forces during trauma, infections within the area of injury; internal causes (related to organism of the injured person) – which include: the degree of nutrition and mineralization of the body (mainly in the field of calcium ions as well as C and D vitamins), and iatrogenic causes (related to the therapeutic procedure), among which are mentioned: the administration of anticoagulants, steroids, certain inflammatory medications and radiotherapy. Since the publication, made by Yasuda (1953) including the results of the piezoelectric effect occurring in the bones, researches are performed to use different methods in order to obtain or accelerate bone healing. Currently, the most studied and scientifically proved method used for this purpose is the application of therapeutic electromagnetic fields. The exact electromagnetic field impact on bone tissues is not known and is the subject of numerous studies. Nevertheless, beneficial effects of the magnetic fields on increased bone mineralization, accelerated angiogenesis, increased rate of DNA synthesis and increased cellular calcium in osteoblasts have been proved. It is believed that these processes are responsible for the observed acceleration of bone union. The union effect resulting from the application of the magnetic field has been described in numerous studies. Summaries of some of those studies you may find below.
Application of the magnetotherapy in the treatment of non-union
The classical studies on the effectiveness of the application of alternating magnetic field for delayed bone union include observations of Bassett, Pilli and Pawluk, who as the first published the results of their observations conducted in patients who failed to achieve bone union through traditional healing method of osteosynthesis and who were largely threatened with amputation. Among the group of 29 patients, they applied the 75 Hz magnetic field for a period of one month. After this period the bone union was achieved in 25 observed patients.
Bassett also conducted a study involving 125 patients with delayed union. They were subjected to the treatment using only the alternating magnetic field generated by a specially prepared for this purpose induction coils. Initially, the treatment was carried out in a complete counterbalanced limb in a cast. X-ray showed an increase in bone density within the area of fracture, long plaster cast was replaced by the short and exercises with a minimum load were introduced (heel touched the ground) in order to increase the piezoelectric effect. Then, in the case of achieving a stronger union confirmed by the radiographic examination, a partial load of limbs was introduced, gradually increasing the weight. The average period of treatment was 5.2 months. 87% of patients were cured. Therapeutic success was not dependent on age and gender of the patient, the time that elapsed between the fracture and implementation of treatment, the number of previous surgeries and possible infection in the area of treatment. Conclusion: The application of an alternating magnetic field in the case of delayed bone union significantly contributes to the union and should be used for this disease entity.
Also to the classical studies we can include Heckman researches, who within a month of therapy with the use of alternating magnetic field obtained the bone union in 64.4% from 149 patients. When the treatment time was extended to three months, this rate increased to 85%. As mentioned above, the cited studies are classical studies on the effect of alternating magnetic field for treatments of delayed union. From the point of view of current research methodology, those studies do not meet the criteria for high scientific credibility. However, in recent years, there are some interesting studies with regard to the highest levels of research reliability. They were double-blind studies using randomization, control group, placebo effect and with an independent assessment of the research results by experts who did not know whether they assessed control or research groups. These studies have confirmed the efficacy of the alternating electromagnetic field in the treatment of delayed union. Their results are reported below.
Sharrard conducted a randomized, double-blind study where participants were assigned to the research group and the control group, in which a placebo was used. The study included 45 people: 20 participants in the research group with the use of an alternating magnetic field, and 25 people in the control group. All tested participants met the criteria for non-union (delayed union). During a period of 12 weeks they were subjected to an alternating magnetic field therapy (study group) or placebo impact – when the unit was off (control group). After completion of the study, patients were again subjected to an independent radiology review. Radiological results were classified according to four categories: 1. Achieved complete bone union, 2 Possible complete bone union, 3 In the phase of bone healing, 4 No changes towards bone union. The research group included three people who achieved complete bone union, two people – with possible complete bone union, five people were in the phase of bone healing, while ten participants did not achieved bone union. In the control group, not a single person has obtained bone union, one person has achieved the possible complete bone union, three people were in the phase of bone healing, while in seventeen participants no changes were observed towards bone union. The other people did not meet the research conditions and they were excluded from the analysis. The study showed a statistically significant difference between the control and study group (p = 0.002). Conclusion: The alternating magnetic field is effective for the treatment of delayed bone union.
Scott and King conducted a double-blind study involving the control group in order to test the effectiveness of the alternating electromagnetic field impact for the treatment of delayed bone union. 23 people participated in the research, while 21 participants were included in the analysis. The research group used the impact of the magnetic field (10 people), while the control group (11 people) was subjected to the placebo effect when the unit is off. After the test completion, the results were evaluated by an independent radiologist and surgeon. In the research group, six out of ten people were considered as cured, while in the control group no person achieved bone union. There was a statistically significant difference between those in the control group and the research group (at P = 0.004). Conclusion: The alternating magnetic field is effective for the treatment of delayed bone union.
The Simon’s study involved 34 people, who had not achieved bone union of the tibial bone within a year after fracture. Participants were randomly (randomization) assigned to the research group (with the applied alternating magnetic field using an inductive coil) and the control group (subjected to the placebo effect with the unit turned off). The study was conducted for a period of six months. At the end of each month, the participants were undergoing an evaluation performed by independent radiologists 24 participants achieved bone union: in the research group – 89% of all patients, while in the control – 50%. The difference between the research group and the control group was found to be statistically significant (p = 0.02). Conclusion: The alternating magnetic field is more effective than the placebo effect in the case of treatment of delayed bone union.
C. A. L. Bassett and R. J. Pawluk: Acceleration of fracture repair by electromagnetic fields. A surgically noninvasive method
C. A. L. Basset i in.: Treatment of ununited tibial diaphyseal fractures with pulsing electromagnetic Fields
W. J. W. Sharrard: A double-blind trial of pulsed electromagnetic fields for delayed fractures of tibial fractures
B. J. Punt, P. T. den Hoed, W. P. J. Fontijne: Pulsed electromagnetic Welds in the treatment of non union
X. L. Griffin, F. Warner, M. Costa: The role of electromagnetic stimulation in the management of established non-union of long bone fractures: What is the evidence?