Adil Surat

Short-segment pedicle instrumentation of thoracolumbar burst fractures: does transpedicular intracorporeal grafting prevent early failure?

Study Design. A prospective, randomized study comparing two treatment methods for thoracolumbar burst fractures: short-segment instrumentation with transpedicular grafting and the same procedure without transpedicular grafting. Objective. To evaluate the efficacy of transpedicular grafting in preventing failure of short-segment fixation for the treatment of thoracolumbar burst fractures. Summary of Background Data. Short-segment pedicle instrumentation for thoracolumbar burst fractures is known to fail early because of the absence of anterior support. Additional transpedicular grafting has been offered as an alternative to prevent this failure. However, there is controversy about the results of transpedicular grafting. Methods. Twenty patients with thoracolumbar burst fractures were included in the study. The inclusion criterion was the presence of fractures through the T11–L3 vertebrae without neurologic compromise. The patients were randomized by a simple method into two groups. Group 1 patients were treated using short-segment instrumentation with transpedicular grafting (TPG) (n = 10), and Group 2 patients were treated by short-segment fixation alone (NTPG) (n = 10). Clinical (Likert’s questionnaire) and radiologic (sagittal index, percentage of anterior body height compression, and local kyphosis) outcomes were analyzed. Results. The two groups were similar in age, follow-up period, and severity of the deformity and fracture. The postoperative and follow-up sagittal index, percentage of anterior body height compression, and average correction loss in local kyphosis in both groups were not significantly different. The failure rate, defined as an increase of 10° or more in local kyphosis and/or screw breakage, was also not significantly different (TPG = 50%, NTPG = 40%, P = 0.99). Conclusions. Short-segment transpedicular instrumentation of thoracolumbar burst fractures is associated with a high rate of failure that cannot be decreased by additional transpedicular intracorporeal grafting.

The evolution of sagittal segmental alignment of the spine during childhood.

Study Design. Cross-sectional. Objectives. The purpose of this study is to describe the normative data of the sagittal plane on pediatric age population, and to document the evolution of sagittal alignment with growth. Summary of Background Data. Having normative data about the sagittal plane is an integral part in the planning of the three-dimensional reconstruction of the spine. Segmental sagittal plane analysis on adults has been studied thoroughly; however, there are inadequate data on children. Methods. A total of 151 children (72 girls, 79 boys) without musculoskeletal abnormality between the ages of 3 to 15 years were studied with the 36-inch standing lateral radiograph with the arms flexed at 30°. There were a minimum of 10 children, at least 4 of them from one sex, in each age group. Variables measured on the radiograms were as follows: segmental angulations from T1–T2 to L5–S1, angles of global kyphosis (T1–T12) and lordosis (L1–S1), segmental angulations of T2–T5, T10–T12, T10–L2, and L4–S1 levels, T1 and L1 offsets in millimeters, location of thoracic and lumbar apexes, and spinopelvic alignment measurements (angles of alpha and beta, sagittal vertebral axis, and sacropelvic translation). For statistical analysis, the children were grouped in terms of ages: Group I (3–6 years of age), Group II (7–9 years of age), Group III (10–12 years of age), and Group IV (13–15 years of age). Results. One-way analysis of variance showed significant differences between the following parameters among groups: segmental angulations of T1–T2 (P = 0.015), T10–L2 (P = 0.014), L4–S1 (P = 0.001), global kyphosis angle (P = 0.005), global lordosis angle (P = 0.000), thoracic apex (P = 0.007), T1 offset (P = 0.000), sagittal vertebral axis (P = 0.004), and beta angle (P = 0.000). As sagittal vertebral axis increases, there is found to be a higher L1 offset and lower thoracic apex, both of which result in leaning forward. With growing, total thoracic kyphosis and total lumbar lordosis particularly due to lower 2 motion segments were found to be increased, while thoracic apex moved upwards, T1 offset increased, and L1 offset decreased. Older children stood with a more negative SVA, and sacral inclination increased. Conclusion. Sagittal spinal alignment is found to be changing as a child grows. There is a statistically significant difference among different age groups, especially at cervicothoracic, thoracolumbar, and lumbosacral junc-tions. The position of the sacrum (inclination and translation), and spatial orientation, as well as the global magnitude of thoracic kyphosis, and lumbar lordosis changes with growth. These findings should be taken into consideration for the young patients who require spinal instrumentation. The question “whether sagittal alignment should be restored according to the normative data for the child’s age or to the normative data for the adulthood” remains to be answered.

Reliability and Validity of Adapted Turkish Version of Scoliosis Research Society-22 (SRS-22) Questionnaire

Study Design. Outcome study to determine the internal consistency, and validity of adapted Turkish version of Scoliosis Research Society-22 (SRS-22) Instrument. Objectives. To evaluate the validity and reliability of adapted Turkish Version of SRS-22 questionnaire. Summary of Background Data. The SRS-22 questionnaire is a widely accepted questionnaire to assess the health-related quality of life for scoliotic patients in the United States. However, its adaptation in languages other than the source language is necessary for its multinational use. Methods. Translation/retranslation of the English version of the SRS-22 was done, and all steps for cross-cultural adaptation process were performed properly by an expert committee. Later, SRS-22 questionnaires and previously validated Short Form-36 (SF-36) outcome instruments were mailed to 82 patients who had been surgically treated for idiopathic scoliosis. All patients had a minimum of 2 years follow-up. Fifty-four patients (66%) responded to the first set of questionnaires. Forty-seven of the first time respondents returned their second survey. The average age of the 47 patients (12 male, 35 female) was 19.8 years (range, 14–31 years). The two measures of reliability as internal consistency and reproducibility were determined by Cronbach α statistics and intraclass correlation coefficient, respectively. Concurrent validity was measured by comparing with an already validated questionnaire (SF-36). Measurement was made using the Pearson correlation coefficient (r). Results. The study demonstrated satisfactory internal consistency with high Cronbach α values for the four of the corresponding domains (pain, 0.72; self-image, 0.80; mental health, 0.72; and satisfaction, 0.83). However, the Cronbach α value for function/activity domain (0.48) was considerably lower than the original questionnaire. The intraclass correlation coefficient for the same domains was 0.80, 0.82, 0.78, 0.81, and 0.76, respectively, demonstrating a satisfactory test/retest reproducibility. Considering concurrent validity, two domains had excellent correlation (r = 0.75–1), while 9 had good correlation (r = 0.50 to 0.75), and 6 had moderate correlation (r =0.25–0.50). Based on these results, question 18 in the function/activity domain with lower Cronbach α value was revised while question 15 was excluded. The revised SRS-22 was given to 30 adolescent idiopathic scoliosis patients not included in the index study. The revision could improve the Cronbach α value for function/activity domain from 0.48 to 0.81. Conclusion. This study demonstrated that, if measures are to be used across cultures, the items must not only be translated well linguistically but also must be culturally adapted to maintain the content validity of the instrument at a conceptual level across different cultures. This may necessitate several validation studies to ensure and improve consistency in the content and face validity between source and target versions of a questionnaire due to difficulty in detecting subtle differences in the living habits of different cultures.

Measurement of vertebral rotation in standing versus supine position in adolescent idiopathic scoliosis

Thirty-three structural curves of 25 patients with adolescent idiopathic scoliosis were evaluated using computed tomography (CT) scans and plain radiography. The average Cobb angle on standing radiographs was 55.72° and was observed to be corrected spontaneously to 39.42° while the patients were in supine position (29.78% correction). Average apical rotation according to Perdriolle was 22.75° on standing radiographs and 16.78° on supine scanograms. The average rotation according to Aaro and Dahlborn on CT scans was 16.48°. Radiographic measurements were significantly different from axial CT slice or scanogram measurements (p = 0.000), but the two latter measurements, both obtained in the supine position, did not appear to be different (p = 0.495). Deformities on the transverse plane as well as on the coronal plane are influenced by patient positioning. If the patient lies supine, the scoliosis curve corrects spontaneously to some degree on both planes. Measurements obtained from the scanograms by the Perdriolle method in the supine position are very similar to those obtained by CT. Perdriolles is a simple, convenient, and reliable method to measure rotation on standing radiograms.

The effect of transpedicular intracorporeal grafting in the treatment of thoracolumbar burst fractures on canal remodeling.

Abstract. Short-segment posterior instrumentation for the treatment of thoracolumbar burst fractures has been reported with a high rate of failure. Transpedicular intracorporeal grafting in combination with short-segment instrumentation has been offered as an alternative to prevent failure. However, concern still remains about the potential complication of further canal narrowing or failure of remodeling with this technique. The purpose of this prospective, randomized, controlled study is to evaluate the effect of transpedicular intracorporeal grafting on spinal canal restoration and remodeling in a group of patients treated with short-segment instrumentation for thoracolumbar burst fractures. Twenty-one patients with thoracolumbar burst fractures were randomised into transpedicular grafting (TPG) (n=11) and non- transpedicular grafting (NTPG) (n=10) groups, and were prospectively followed for an average of 50 months (range 25–85 months). Groups were similar in age, type of fracture, load sharing classification and kyphotic deformity. Preoperative, postoperative and follow-up computed tomographic (CT) images through the level of pedicles were obtained, corrected for differences in magnification, and digitized. Areas of the spinal canals were measured and normalized by the estimated area at that level (average of adjacent levels). Average kyphosis was 19.7°±6.2° at presentation, was corrected to 1.9°±4.9° by operation, but was found to have deteriorated to 9.1°±6.4° at final follow-up. There were no differences between groups regarding the evolution of sagittal deformity. Spinal canal narrowing was 38.5±18.2% at presentation, 22.1±19.8% postoperatively, and it further improved to –2.5±16.7% at follow-up, similar for both groups. Our results demonstrate that transpedicular intracorporeal grafting in the treatment of burst fractures does not have a detectable effect on the rate of reconstruction of the canal area or on remodeling. Spinal canal remodeling was observed to occur in all patients regardless of grafting.

Atlantoaxial rotatory fixation-subluxation revisited: a computed tomographic analysis of acute torticollis in pediatric patients.

Study Design. Cross-sectional clinical and radiologic study with a normal control group. Objectives. To compare the range of motion of the atlantoaxial joint in patients with acute torticollis with those of normals as measured from computed tomography scans, to look for the existence of atlantoaxial rotatory fixation in any position (subluxation or normal range of motion) in this group of patients, and to clarify the definition of atlantoaxial rotatory subluxation by measuring the atlantodental interval and analyzing the location of the center of rotation in patients as well as normal controls. Summary of Background Data. Although acute acquired torticollis is usually termed atlantoaxial rotatory subluxation or atlantoaxial rotatory fixation, the radiologic definition of these conditions is not clear. Patients and Methods. Thirty-three consecutive pediatric patients (average age 8.5 years, range 2–18 years) with acute acquired torticollis were analyzed. All were neurologically intact. Anteroposterior and lateral radiographs were obtained in all atlantoaxial computed tomography scans in 31 patients (dynamic in 23 and static in 8). Twelve age-matched patients with normal cervical spines were also analyzed with dynamic computed tomography as normal controls. Atlantoaxial rotatory subluxation, atlantoaxial angle, center of rotation, and presence of atlantoaxial rotatory fixation were analyzed in each computed tomography. All patients were treated conservatively. Eight had control dynamic computed tomography scans at the end of the treatment. Results. All patients had atlantoaxial rotatory subluxation ≤3 mm. On dynamic computed tomography, the range of atlantoaxial rotation was 30.4° (range 11–54°) toward deformity and 28.3° (range 18–54°) away from deformity (P = 0.333). Atlantoaxial rotatory fixation was not noted in any of the patients. The same measurement for the normal control group was 28° (range 5–41°) (P = 0.770). Of the eight patients with repeat control computed tomography, the atlantoaxial rotatory subluxation was 26° before and 29° after treatment (P = 0.691 to right and P = 0.199 to left). The center of rotation was within dens in 15 of 19 patients, outside dens in 2 of 19, and undetectable in 2 of 19. In the control group, it was within dens in 8 of 11, outside dens in 2 of 11, and undetectable in 1 of 11. All patients were symptom free at the end of the conservative treatment. Conclusion. We could not demonstrate the presence of atlantoaxial rotatory subluxation or atlantoaxial rotatory fixation in our series of 33 consecutive pediatric patients with acute torticollis. Our findings suggest that the existence of these phenomena are doubtful, although not associated with acute acquired torticollis. Acute acquired torticollis is not necessarily the sign of a pathologic condition of the atlantoaxial joint. Finally, it is probably not necessary to obtain computed tomography scans (static or dynamic) in this group of patients at the time of presentation.

Course of nonsurgical management of burst fractures with intact posterior ligamentous complex: an MRI study.

Study Design. Prospective study. Objectives. To evaluate the results of nonsurgical management of burst fractures with intact posterior ligamentous complex and to investigate the effect of trauma and/or residual kyphotic deformity on adjacent and next adjacent (neighboring) discs. Summary of Background Data. Conservative treatment based on integrity of posterior ligamentous complex is controversial, probably because of poor evaluation by clinical and indirect radiographic findings. Degenerative changes in the adjacent discs due to trauma and/or residual kyphotic deformity is a common expectation. Material and Methods. Fifteen consecutive patients who were intact neurologically with burst fractures (T11-L2) were treated nonsurgically with the indication based solely on the integrity of posterior ligamentous complex determined by MRI. Correction of deformity and stabilization with a total body cast under sedation were the mainstays of treatment. Patients were mobilized the next day, and casts were removed at the end of the third month follow-up period with no further external stabilization. Local kyphosis angle, sagittal index, and percent of compression of anterior body height were measured on pretreatment, post-treatment, third month, and latest follow-up radiographs. All of the preoperative and latest follow-up MRI studies of the patients were obtained to examine the discs adjacent and next adjacent to the fractured levels. The self-reported perceptions of the patients of function, pain and appearance were analyzed using the Likert Questionnaire. Results. There were eight female and seven male patients with an average age of 28 (range, 15–49) years. Average follow-up period was 31 (range, 24–51) months. Average local kyphosis angle was found to be 16.5° (0–34°) after trauma. It was corrected to 5° (range, 19–25°) and deteriorated to 14.6° (range, 2–25°) at the third month and to 17° (range, 2–29°) at the final follow-up review. There was a similar tendency for both sagittal index and percent anterior body height. The pretreatment MRI analysis revealed changes in the shape of the discs (narrowing or herniation into the body) with no change in the signal intensity of nucleus pulposus in eight of the cranial and four of the caudal adjacent discs. On follow-up MRI, there was only one intact disc with a normal shape cranially. All others had height loss, but only one had complete loss of signal intensity. Caudally, two additional discs had changes in shape without any gross changes in signal intensity of nucleus pulposus, whereas two had changes in signal intensity without change in shape. Only two of the next adjacent discs had changes in shape or signal intensity at the time of injury or at latest follow-up review. Average score of function, pain, and appearance were 3.9 (range, 3–5), 3.7 (range, 2–5), and 3.7 (range, 2–5), respectively, at the latest follow-up review. All patients were back at work in 3.6 (range, 1–9) months on average and all were satisfied with their treatment. Conclusions. The present study revealed that an intact posterior ligamentous complex might not prevent loss of correction gained by nonsurgical management of burst fractures. Significant loss occurs in the first 3 months despite external stabilization. However, the magnitude of residual deformity usually remains close to the initial deformity. Although changes in the shape of adjacent discs occur due to trauma and/or natural course, significant loss in signal intensity of nucleus pulposus is unlikely. Patient outcome seems to be highly satisfactory despite residual deformity.

The effect of pedicle screw placement with or without application of compression across the neurocentral cartilage on the morphology of the spinal canal and pedicle in immature pigs.

Study Design. Experimental study. Objectives. To investigate the effects of pedicle screw insertion on spinal canal and pedicle morphology in immature pigs, and, if transpedicular fixation has an effect, to document whether this occurs because of the inhabitance of the screw inside the growth plate (neurocentral cartilage [NCC]) or because of compression applied across the NCC. Summary of Background Data. Transpedicular fixation has been less commonly applied to the pediatric population, especially because of the risk of damage to the NCC. Methods. Twelve newborn pigs (4−6 weeks of age) were operated on. Left sided pedicles from L1–L5 were studied, while right sides served as controls. Pigs were randomly assigned into 3 groups: (1) pedicles were probed only; (2) screws were inserted; and (3) after screw insertion, a washer and a nut were engaged at the pedicle entry point so that gradual compression across the NCC was achieved. After 4 months, spiral computerized tomography was used to measure the pedicle lengths and size of the halves of the spinal canal. Results. In group 1, the operated hemi-canal area was not statistically different from the nonoperated side (P = 0.159). Pedicle screw insertion either with (P = 0.007) or without (P = 0.005) compression resulted in smaller hemi-canal area and shorter pedicles at the operated side, respectively (P = 0.008, P = 0.021). Approximately 4% to 9% shortening of the pedicle lengths and 20% to 26% narrowing of the hemi-canal areas on the instrumented side occurred with transpedicular instrumentation (groups 2, 3). Conclusion. Even without compression, pedicle screws passing through the NCC in immature pigs disturb spinal canal growth significantly. Clinical relevance for young children should be studied further.

Effects of deamino-8-d-arginin vasopressin on blood loss and coagulation factors in scoliosis surgery : a double-blind randomized clinical trial

STUDY DESIGN A double-blind, randomized, prospective clinical study was performed to evaluate the efficacy of deamino-8-D-arginin vasopressin in reducing blood loss in major scoliosis surgery. OBJECTIVES To evaluate whether desmopressin has any effect on reducing blood loss in spinal surgery, to identify the probable mechanisms of effectiveness via blood coagulation factors, and to outline any adverse effect associated with the use of deamino-8-D-arginin vasopressin. SUMMARY OF BACKGROUND DATA Scoliosis surgery is known to be associated with major blood loss. Because of major drawbacks of homologous blood transfusion, many alternative methods have been used to counter the blood loss. Only a few studies exist, with controversial results, on the use of deamino-8-D-arginin vasopressin. METHODS The study population included 40 operations on 35 consecutive patients undergoing reconstructive surgery for either idiopathic (n = 26) or congenital (n = 9) scoliosis. Operations were randomized into deamino-8-D-arginin vasopressin (0.3 microgram/kg body weight; maximum, 20 micrograms) (n = 18) or placebo (n = 22) groups and stratified according to the diagnosis and the type of surgery performed (i.e., anterior versus posterior versus anterior and posterior sequential). Parameters of blood loss, serum levels of blood coagulation factors at different time intervals, and urinary output were measured. RESULTS Findings indicated that blood loss per kilogram of body weight, blood loss per surgically treated spinal level, urinary output per kilogram of body weight and serum levels of fibrinogen, von Willebrand factor (vWF) activity, tissue type plasminogen activator activity, and plasminogen activator inhibitor activity were not sensitive to the administration of deamino-8-D-arginin vasopressin at any time interval during surgery or at 24 hours after surgery (P > 0.05). Only factor VIII:C levels exhibited significant elevations at 30 minutes and at 24 hours (P < 0.05). CONCLUSIONS This study could not demonstrate any significant effect of deamino-8-D-arginin vasopressin on the amount of blood loss in a group of patients with idiopathic or congenital scoliosis. Findings indicate that for most of the coagulation factors, any changes in serum levels induced by deamino-8-D-arginin vasopressin were much like those expected from surgery itself. This study also failed to demonstrate any significant effects altering the urinary output that may be attributed to the use of deamino-8-D-arginin vasopressin.

Three-dimensional evolution of scoliotic curve during instrumentation without fusion in young children.

This study respectively evaluated 12 young children with progressive curves who underwent subcutaneous rod instrumentation (SCRI) without fusion and were followed until definitive surgery. The mean curve Cobb angle was 58° at the time of SCRI. The mean apical vertebral rotation at the time of presentation was 20°. Curves were observed to have progressed to an average of 59° before definitive surgery and were corrected to 34° with instrumentation. The average apical vertebral rotation was found to be 34° before the definitive treatment. This value was significantly larger than the pre-SCRI value (P = 0.002). The average number of lengthening operations per patient was 4.6, and the number of all operations per patient was 7. Six patients developed complications. The average time spent in hospital was 101 days. The findings demonstrate that the curves were essentially unchanged in the frontal plane during the period of lengthening. The sagittal curves remained mostly within normal limits, but there was an alarming increase in rotation.