EPIDEMIOLOGICAL DATA OF ACQUIRED SKULL DEFECTS IN PATIENTS AFTER TRAUMATIC BRAIN INJURY THROUGH THE EXAMPLE OF A BIG INDUSTRIAL CITY (NOVOSIBIRSK) Stupak V.V., Koporushko N.A., Mishinov S.V., Guzev A.K., Astrakov S.V., Vardosanidze V.K., Golobokov A.V., Bobylev A.G.
Tsivyan Research Institute of Traumatology and Orthopedics,
City Clinical Hospital No.25,
City Clinical Hospital No.1,
City Clinical Hospital No.34,
Novosibirsk Regional Clinical Hospital, Novosibirsk, Russia
The consequences of traumatic brain injury are the important medicosocial problem both in Russia and other world [1, 2] since patients have the consequences of neurological, therapeutic and psychological characteristics [3]. It is known that the surgically significant consequences of traumatic brain injury (TBI) are defects of cranial bones [4], which can cause syndrome of the trephined (SoT). The common complaints of patients with SoT are headache in region of resection trepanation, discomfort in region of a defect during coughing, sneezing, inclination of the head, and during physical load [5]. Organic lesion of the brain often causes the scar-adhesion process between dura matter and adjacent cerebral tissue in the region of a defect. It promotes the development of epileptic seizures and focal symptoms [4]. Patient who received resection of cranial bones, especially in cerebral region in the site of superior part of facial bones, have some complaints of extensive and cosmetic defects, which are often disfiguring, resulting in psychological problems [6]. Such patients address to physician with issues of surgical interventions for bone defect closure. According to Clinical Recommendations for Reconstructive Surgery of Cranial Defects (14 October 2015), the indications for cranioplasty in patients with cranial bone defects have not determined clearly, but cosmetic indications are dominating [7]. The foreign literature shows that previous decompressive cranioectomy is not the indication for cranioplasty [8, 9].
All patients with cranial bone defects are usually persons of working age who are disabled after previous accidents. Their fast rehabilitation and return to professional activity are the important socioeconomic tasks. After review of Russian and foreign literature, we concluded that the uniform system for registration of patients with acquired defect is absent. The retrospective analysis was conducted for determination of amount of patients and incidence of defects. The analysis was based on the examples of hospitals in a big industrial city (Novosibirsk) which render assistance for patients with TBI.
The study objective – by the example of a big industrial city (Novosibirsk), to determine the number of patients with traumatic brain injury and acquired defects of cranial bones, with planned reconstructive surgery for defects closure.
MATERIALS AND METHODS
The patients with acquired cranial bone defects were examined for the five-year period (1 January 2013 – 31 December 2017). The analysis was based on the results of surgical experience in six units and clinics of Novosibirsk city, which arrange the urgent care for patients with traumatic brain injury.
The analysis included the following parameters: age, gender, number of patients, amount of operations, number of defects and their square, trepanation sites, disease outcomes. Also the mean number of patients with acquired defects, and the incidence of defects per 100,000 of population of Novosibirsk were estimated. Calculation and distribution of defect according to their size in compliance with the scale of Association of Neurosurgeons, 2015 were carried out.
The article presents the descriptive statistical analysis with Statistica 10 software. The results are presented as M ± m, where M – mean arithmetic, m – error of mean. The groups were not compared against each other.
The study was conducted in compliance with World Medical Association Declaration of Helsinki – Ethical Principles for Medical Research Involving Human Subjects, 2013, and the Rules for Clinical Practice in the Russian Federation (19 June 2003, No.266). It was approved by the biomedical ethical committee of Tsivyan Research Institute of Traumatology and Orthopedics (the protocol No.061/18, 13 November 2018).
RESULTS
729 patients with traumatic brain injury of various severity received urgent surgical intervention during the above mentioned period. They received 752 cranioectomy procedures. As result, the same number of cranial defects appeared. The mean age of the patients was 47.6 ± 0.62. There were 604 men and 125 women. Among 729 operated patients, 430 (59 %) patients were discharged for outpatient treatment according to the places of their residence. 229 (41 %) patients died because of severity of cerebral injury and complications. Therefore, the number of patients with acquired defects was 430, the general number of defects – 436.
Among the mentioned amount, the number of defect in dependence on amount of fields involved in trepanation and their square were studied (the table 1). The last one was calculated with the ellipse square formula (S = πRr, where S – square, π – the value = 3.1415, R – big semi-axis of ellipse, r – small semi-axis) since the ellipse is the geometrical figure having most similarities with the form of a trepanation defect.
Table 1
Distribution of patients depending on number of trephined sites, %, M ± m
|
Total number of defects
|
Trepanation sites
|
Mean square of defects (cm2) |
|||
|
One |
Two |
Three |
Four |
||
|
436 (100 %)
|
90 (20.5 %)
|
226 (51.6 %)
|
117 (27.2 %)
|
3 (0.7 %) |
57.72 ± 1.53
|
As the table 1 shows, the cranial bone defects had two most common locations – 226 (51.6 %). Minimal amount of 3 defects (0.7 %) were in four regions.
Parietal (389 cases, 42.7 %) and temporal (344 cases, 37.8 %) regions were the most common fields involved in the trepanation region. 52 defects (16.7 %) were in the frontal region. The lowest amount of defects was in the occipital region – 26 (2.8 %).
The patients who were included into the study were operated for brain compression caused by depressed skull fractures, intracranial hematomas, contusion foci and progressing cerebral edema. The squares of the defects varied from small to big size. According to the clinical recommendations from Association of Neurosurgeons of Russia, the sizes of skull defects are divided into small (square up to 10 cm2), middle (up to 30 cm2), big (up to 60 cm2) and extensive (> 60 cm2) [6]. On the basis of the general number (436) of formed defects over 5 years of the study, the numbers of defects were calculated: 32 (7.3 %) small, 65 (14.9 %) middle, 138 (31.7 %) big and 201 (46.1 %) extensive defects.
The mean square of a defect in the surgical patients was 57.72 ± 1.53 cm2, i.e. big size. The minimal defect was 3.97 cm2. It appeared after removal of a depressed fracture of the skull base. The maximal defect (212.05 cm2) was in a patient with multiple contusion foci and progressing cerebral edema.
The table 2 shows the annual distribution of numbers of defects on the basis of the general number (436) of acquired defects. Therefore, 87 iatrogenic defects appear in patients with TBI in Novosibirsk each year.
Table 2
Year distribution of number of cranial numbers
|
|
2013
|
2014 |
2015 |
2016 |
2017 |
|
Number of defects |
84 (19.3 %) |
98 (22.5 %) |
81 (18.6 %) |
74 (16.9 %) |
99 (22.7 %) |
|
Population of Novosibirsk |
1523801 |
1547910 |
1567087 |
1584138 |
1602915 |
Also we conducted the analysis of the number (per 100,000 of population of Novosibirsk) of post-trepanation defects among survived patients with use of the formula: the number of acquired defects / mean annual number of population × 100,000 (the table 3).
Table 3
Annual number of new post-trepanation defects per 100,000 of population in Novosibirsk
|
2013 |
2014 |
2015 |
2016 |
2017 |
|
5.51 |
6.33 |
5.16 |
4.67 |
6.17 |
The average number of recurrent cranial defects was 5.56 cases per 100,000 of population in Novosibirsk. Among the general amount of the patients (436 patients), 351 (81.6 %) patients were working age persons at the age 18-60. Among the annual general amount of 87 bone defects in Novosibirsk, 6.9 % of cases were classified as small, 14.9 % – as middle, 32.2 % – as big, 46 % – as extensive.
The received data shows that 68 patient (78.2 %) with big and extensive defects need for reconstructive surgery (according to the program of high tech medical care of Russian Health Ministry) each year.
DISCUSSION
The conducted analysis shows that the number of patients with artificial cranial bone defects after TBI demonstrates the similar annual level. The importance of the problem of surgical reconstruction of the skull has been confirmed.
The above-mentioned surgical interventions can be conducted with use of two types of implants: standard and individual. The standard implants are formed during surgery (with sterile surgical tools). The individual ones are made for each patient. The individual implants have the advantages for extensive or cosmetically important defects. It is explained by the fact that the maximal size of the common titanium mesh is 120 × 120 mm. The most popular produced implants are 100 × 100 mm. It does not cover the defects with size > 153.9 cm2 (with consideration of required overlap for fixation of the implant to the bone). Even if polymer material has sufficient size for closing the whole defect, the surgeon may have wrong ideas about curvature of the operated skull region in view of limited surgical field. With increasing square of the implant, this error increases also. In cases when defects impact the superior defects of facial skeleton (orbit edge, malar process), intrasurgical formation of the implant can take long time as well as in cases with extensive defects, the cosmetic result is sometimes unachievable.
The use of individual implants is regulated according to the program of state warranty for arrangement of high tech care for population, the section Neurourgery 8.010.17 – microsurgical reconstruction for inborn and acquired complex and big defects and deformation of the skull base, facial skeleton and the skull base with use of computer and stereolithographic modeling with use of biocompatible plastic materials and resource-consuming implants. Up to the present time, the individual implants were produced indirectly with use of anatomical models and press-forms [5, 10].
The emergence of devices for additive manufacturing (3D printers) allowed direct production of biocompatible medical products without transitional stages and products [11]. The practical implementation of modern industrial technologies will allow rendering this type of medical care at the advanced level in the world.
The results of the study concerning the amount of patients with cranial defects and the need for their closure allow receiving the enough full picture of this problem in a big industrial city. In its turn, it will allow timely and substantiated planning the financial provision in regional and federal department of healthcare.
According to our data, 22 % of all cranial bone defects require for surgical reconstruction, 78 % of cases require for high tech medical care at the regional level with obligatory medical insurance program.
CONCLUSION
1. 87 iatrogenic skull defects appear in patients with traumatic brain injury in Novosibirsk each year. The average amount of recurrent defects is 5.56 cases per 100,000 of population.
2. 78 % of patients require for reconstructive surgery for closure of cranial defects with the program of high tech medical care of Russian Health Ministry each year.
Information on financing and conflict of interests
The study was conducted without sponsorship.
The authors declare the absence of any clear or potential conflicts of interests relating to publication of this article.