[S2 Alar-Iliac Screws in Fixation and Correction of Combined Neuromuscular Spinal and Pelvic Deformities]. / S2 alar-iliac srouby pri fixaci a korekci kombinovaných neuromuskulárních deformit pátere a pánve.

PURPOSE OF THE STUDY Neuromuscular deformities of the spine represent surgically uneasy to solve problems as well as serious handicaps causing sitting instability, pressure ulcers as well as pain. The aim of our study is to conduct a retrospective clinical analysis of the results of surgical correction of these deformities. This paper presents the use of a recent technique of sacral-alar-iliac (S2AI) screws and its comparison with other techniques of pelvic stabilisation. MATERIAL AND METHODS The group of 41 patients treated surgically with S2AI screws technique and transpedicular or hybrid instrumentation of the spine consisted of patients with the primary diagnosis of muscular dysthrophy, spinal muscular atrophy, cerebral palsy and some other neuromuscular diseases. The results of pelvic obliquity correction and scoliotic correction in combined neuromuscular deformities of the spine and pelvis were analysed. The technique of S2AI screws implantation and the possibility of their free-hand technique implementation were presented. RESULTS In the followed-up group of patients an average correction of pelvic obliquity by 81% (from 29.1 degrees before the operation to 5.6 degrees after the operation) was reported. On average, 74% correction of scoliotic spine deformity was achieved (from 83.3 degrees before the operation to 22.5 degrees after the operation). In both the cases neither a significant loss of correction at the minimum one-year follow-up nor any serious complications associated with grappling of pelvic fixation were observed. DISCUSSION The S2AI screws offer at least the same stability and ability of correction as iliac screws and at the same time they provide significantly better results compared with the older methods of pelvic fixation such as the Galvestone technique. With a good knowledge of the surgical technique and anatomical aspects this technique can be applied in the form of a free-hand technique. Navigation as well as robotic techniques can help with the accurate positioning of the S2AI screw. Transfixation of sacroiliacal syndesmosis in patients with a neuromuscular handicap does not lead to deterioration of their mobility. CONCLUSIONS Simultaneous stabilisation of spine and pelvis makes it possible to achieve a good quality correction of the deformity and good clinical results over a long period of time. It allows for stability of the sitting position of the patients and improves the quality of their lives. Nowadays, the S2AI screws are considered to be biomechanically the best quality pelvic fixation, eliminating subcutaneous prominence of the instrumentation and reducing the risk of skin decubitus. Key words:neuromuscular deformity, sacral-alar-iliac screw, pelvic obliquity, stabilization, scoliosis.

[Comparison of two surgical methods for treatment of idiopathic thoracic scoliosis - anterior versus posterior approaches]. / Srovnání výsledku dvou typu operacního lécení idiopatických hrudních krivek - prední versus zadní výkon.

PURPOSE OF THE STUDY: The aim of this retrospective randomised study is a comparison of two surgical approaches (anterior versus posterior) for the treatment of idiopathic thoracic scoliosis by corrective spondylodesis with segmental instrumentation in adolescents aged 13 to 20 years. MATERIAL AND METHODS: The study included patients with right-sided idiopathic thoracic scoliosis (Cobb's angle, 40°-70°; Lenke type I). The group of patients treated from the posterior approach by fusion and segmental instrumentation, involving the use of a hybrid, tworod system or screws only, comprised 31 girls with an average age of 14.5 years (group 1). In this group three instrumentation systems were used. The patients treated from the anterior approach, which included thoracotomy for disc excision, fusion and segmental instrumentation with a one- or two-rod system, consisted of 25 girls and six boys with an average age of 15.3 years (group 2). In this group four instrumentation systems were employed. In all patients radiographs were evaluated before surgery, immediately after the procedure and then every 12 months. The evaluation also included the operative time, blood loss, length of hospital stay, hospital costs and complications. The random selection was based on casting lots. Some patients indicated for the anterior approach withdrew after receiving detailed information on this procedure and therefore patients operated on from the anterior approach before the study had begun were enrolled. The statistical comparison of the results of anterior and posterior procedures was made using the two-sample t-test or Wilcoxon's test. The Shapiro-Wilk test was used for normality testing and Fisher's F-test for the equality of variances. The paired t-test or non-parametric paired Wilcoxon's test was employed for testing two variables within each group. The level of significance was set at 0.05. RESULTS In group 1, anteroposterior radiographs showed, on the average, 54.3° before surgery, 18.7° immediately after it and 19.1° at one year after surgery. The sagittal profile before surgery was T5 +30.0° T12 -57.7° S1; the surgery resulted in reducing thoracic kyphosis by 9.5° and lumbar lordosis by 14.2°. The average operative time was 245.8 min, intra-operative blood loss was 1095.2 ml and drained blood loss was 636.9 ml. The average hospital stay lasted 10.2 days. In group 2, anteroposterior radiographs had the average values of 53.7° pre-operatively, 23.6° post-operatively and 25.9° at one year after surgery. The pre-operative sagittal profile was T5 +21.5° T12 -54.2° S1 and, post-operatively, thoracic kyphosis increased by 7.0° and lumbar lordosis decreased by 2.2°. The average operative time was 226.8 min, intra-operative and drained blood losses were 1095.2 ml and 636.9 ml, respectively, and length of hospital stay was 15.5 days.. In group 2, the operative time and intra-operative blood loss were lower and post-operative drained blood loss (due to longer duration of chest drainage) was higher than in group 1. All findings were statistically significant. Significant differences between the groups were also found in the costs of implants and hospital stay because, for the posterior approach, they were higher by a total of 68 466 CZK and 52 250 CZK, respectively. DISCUSSION: In the frontal plane, thoracic kyphosis corrections through either surgical approach are comparable; in the sagittal plane, surgery from the posterior approach results in reducing thoracic kyphosis and that from the anterior approach produces a mild increase in it. CONCLUSIONS: In terms of surgical treatment selection, the anterior approach is more economical and requires spinal fixation and instrumentation to a lesser extent. However, prolonged chest wound drainage results in a longer hospital stay. The majority of idiopathic scoliosis cases are indicated for a posterior approach. In scoliosis with marked hypo-kyphosis or lordosis, an anterior approach can be considered because it produces an increase in thoracic kyphosis.

[Infections in surgery of idiopathic scoliosis]. / Infekce pri operaci idiopatické skoliózy.

PURPOSE OF THE STUDY: In this retrospective study, we evaluated infectious complications in the patients undergoing surgical treatment for idiopathic scolions in order to identify risk factors for postoperative infections. MATERIAL: A total of 786 patients with idiopathic scoliosis were operated on during 24 years. In 754 (96%) cases, we used the posterior approach, involving posterior fusion and internal fixation, and subsequent immobilization in a brace. During that period, we recorded 15 (1.9%) deep wound infections in the area of fusion. Early infections were treated by debridement and lavage, with targeted administration of antibiotics, while instrumentation was kept in place. In late und recurrent infections, instrumentation was always removed. METHODS: We investigated a relationship between the infectious agent and the device used, the length of period between surgery and the onset of infection, the effect of device removal on curve progression, the agent causing infection and the effect of allergy to metal or infectious lesions at other body sites on the outbreak of infection. RESULTS: Early infections (within 6 weeks) were observed in six, late in nine patients. Repeat operations were necessary on average after 487 days. Staphylococcus aureus, the most frequent infectious agent, was isolated from four patients; on four occasions, cultivation was negative. Allergy to nickel was found in four patients. Infection was most often associated with the most frequently used Harrington Instrumentation (six cases, 1.1%). However, in relation to the number of patients treated, infection frequency was highest in TSRH (5.0%) and Isola (4.8%) devices. When Miami Moss fixation or the anterior approach was used, no infection was recorded. In comparison with the non-infected cases, the patients with infectious complications showed the same average values for the curve before and after surgery. At a check up, however, the loss of correction increased to 6 degrees and, after instrumentation removal, to 10 degrees as against 3 degrees in the non-infected patients. Pseudoarthrosis developed in two cases. DISCUSSION: The incidence of deep wound infections in patients who had surgery for idiopathic scoliosis was comparable with the data in the relevant literature. A higher number of infections, particularly late ones, in patients treated with the use of modern instrumentation is probably related to a higher volume of these implants. Early infections are a rare feature and their cause is known (allergy, sepsis). Treatment involves surgical intervention; in early infections, instrumentation is retained but is removed in late infections. CONCLUSIONS: Even though our group included a low number of patients with infections, we can conclude that risk factors for the development of infectious complications associated with surgical treatment of idiopathic scoliosis are as follows: allergy, higher age, large volume of metal used for stabilization and the presence of another infectious lesion.