Transforaminal Lumbar Interbody Fusion in Degenerative Disk Disease and Spondylolisthesis Grade I: Minimally Invasive Versus Open Surgery.

BACKGROUND: Interbody fusion represents an efficient surgical treatment in degenerative lumbar disease, achieving satisfying outcome in >90% of cases. Various studies have affirmed the advantages of percutaneous and minimally invasive techniques with regard to minimized damage on soft tissues during surgical procedure, but their efficacy in comparison with the classic open surgical procedures has not yet been demonstrated. MATERIALS AND METHODS: This is a retrospective study. We compared 30 consecutive patients affected by disk degenerative disease or grade I degenerative spondylolisthesis that were treated with minimally invasive transforaminal lumbar interbody fusion (mini-TLIF) to a group of 34 consecutive patients presenting similar pathologic findings and demographic characteristics that underwent interbody fusion by traditional open approach (open-TLIF). All patients were treated between 2006 and 2010. Patients' mean age was 46 years (min 28-max 56) and 51 years (min 32-max 58), respectively. Mean follow-up was 23 months (min 12-max 38) and 25 months (min 12-max 40), respectively. Clinical evaluation was performed by using Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) questionnaires. Radiographic evaluation was performed on standing and dynamic x-rays before operation and at final follow-up. RESULTS: There was a statistically significant improvement in clinical scores (VAS and ODI) in both groups. Early postoperative VAS score was significantly lower in the mini-TLIF group. Mean hospital stay and mean blood loss were significantly higher in the open-TLIF group than in the mini-TLIF group (7.4 vs. 4.1 d and 620 vs. 230 mL, respectively). Surgical time length of the procedure was higher in the mini-TLIF group. There were no major neurological complications in any of the patients. At final follow-up, radiographic evaluation showed good implant stability in both groups. CONCLUSIONS: Mini-TLIF is a safe and efficient procedure and, when correctly and carefully performed, can reach good results, similar to those obtained with traditional open surgical techniques, even though it may require a longer surgical time at least during the first stages of the learning curve. Reduced surgical invasiveness, short hospital stay, and limited blood loss represent the major advantages of minimally invasive technique.

Thoracic pedicle subtraction osteotomy in the treatment of severe pediatric deformities.

The traditional surgical treatment of severe spinal deformities, both in adult and pediatric patients, consisted of a 360° approach. Posterior-based spinal osteotomy has recently been reported as a useful and safe technique in maximizing kyphosis and/or kyphoscoliosis correction. It obviates the deleterious effects of an anterior approach and can increase the magnitude of correction both in the coronal and sagittal plane. There are few reports in the literature focusing on the surgical treatment of severe spinal deformities in large pediatric-only series (age <16 years old) by means of a posterior-based spinal osteotomy, with no consistent results on the use of a single posterior-based thoracic pedicle subtraction osteotomy in the treatment of such challenging group of patients. The purpose of the present study was to review our operative experience with pediatric patients undergoing a single level PSO for the correction of thoracic kyphosis/kyphoscoliosis in the region of the spinal cord (T12 and cephalad), and determine the safety and efficacy of posterior thoracic pedicle subtraction osteotomy (PSO) in the treatment of severe pediatric deformities. A retrospective review was performed on 12 consecutive pediatric patients (6 F, 6 M) treated by means of a posterior thoracic PSO between 2002 and 2006 in a single Institution. Average age at surgery was 12.6 years (range, 9-16), whereas the deformity was due to a severe juvenile idiopathic scoliosis in seven cases (average preoperative main thoracic 113°; 90-135); an infantile idiopathic scoliosis in two cases (preoperative main thoracic of 95° and 105°, respectively); a post-laminectomy kypho-scoliosis of 95° (for a intra-medullar ependimoma); an angular kypho-scoliosis due to a spondylo-epiphisary dysplasia (already operated on four times); and a sharp congenital kypho-scoliosis (already operated on by means of a anterior-posterior in situ fusion). In all patients a pedicle screws instrumentation was used, under continuous intra-operative neuromonitoring (SSEP, NMEP, EMG). At an average follow-up of 2.4 years (range, 2-6) the main thoracic curve showed a mean correction of 61°, or a 62.3% (range, 55-70%), with an average thoracic kyphosis of 38.5° (range, 30°-45°), for an overall correction of 65% (range, 60-72%). Mean estimated intra-operative blood loss accounted 19.3 cc/kg (range, 7.7-27.27). In a single case (a post-laminectomy kypho-scoliosis) a complete loss of NMEP occurred, promptly assessed by loosening of the initial correction, with a final negative wake-up test. No permanent neurologic damage, or instrumentation related complications, were observed. According to our experience, posterior-based thoracic pedicle subtraction osteotomies represent a valuable tool in the surgical treatment of severe pediatric spinal deformities, even in revision cases. A dramatic correction of both the coronal and sagittal profile may be achieved. Mandatory the use of a pedicle screws-only instrumentation and a continuous intra-operative neuromonitoring to obviate catastrophic neurologic complications.

Pulmonary function after thoracoplasty in the surgical treatment of adolescent idiopathic scoliosis.

STUDY DESIGN: Retrospective case series review. OBJECTIVE: To compare two similar groups of adolescents surgically treated for their spinal deformity either by posterior segmental fusion alone (PSF) or by posterior spinal fusion and thoracoplasty (PSF+T); attention was focused on the long-term effects of thoracoplasty on pulmonary function in the surgical treatment of adolescent idiopathic scoliosis. SUMMARY OF BACKGROUND DATA: Posterior spinal arthrodesis with thoracoplasty and an open anterior approach, with respect to a posterior only fusion have been found to have a deleterious effect on pulmonary function for as long as five years postoperatively after surgical treatment of adolescent idiopathic scoliosis. METHODS: A group of 40 consecutive adolescent patients, surgically treated between 1998 and 2001 by posterior spinal fusion and thoracoplasty, was compared with a similar cohort of 40 adolescents treated in the same period by posterior segmental fusion alone. Pedicle screw instrumentation alone and a minimum five-year follow-up were requested as inclusion criteria. Both a radiographic analysis and a chart review was performed, evaluating the pulmonary function tests (PFTs), the SRS-30 score questionnaire and the Lenke classification system. A radiographic Rib Hump (RH) assessment was also performed. RESULTS: The entire series was reviewed at an average clinical follow-up of 8.3 years. There were no statistically significant differences between the two groups in terms of gender, age (PSF+T: 16.3 y vs. PSF: 15.2 y), Lenke curve type classification and preoperative Cobb's main thoracic (MT) curve magnitude (PSF+T: 66° vs. PSF: 63°), whereas both final MT percent correction (PSF+T: 53.03% vs. PSF: 51.35%; P<0.03), RH absolute correction (PSF+T: -2.1 cm vs. PSF: -1.05; P<0.01) and RH overall percent correction (PSF+T: 55.4% vs. PSF: 35.4%; P<0.0001) were greater in the thoracoplasty group. No statistical differences were observed between the two groups in PFTs both pre-operatively and at last follow-up. Nevertheless, comparing preoperative to final PFT'S within each group, only in the PSF group both forced vital capacity and forced expiratory volume in one second showed a statistically significant improvement at final evaluation. At last follow-up visit, the SRS-30 scores did not show any statistical difference between the two groups (total score PSF+T: 4.1 vs. PSF: 4.3). CONCLUSIONS: Our findings suggest that thoracoplasty did not adversely affect long-term PFTs in AIS patients treated by posterior spinal fusion alone using pedicle screws instrumentation, as already highlighted by previous reports. A trend towards better coronal plane correction and rib hump improvement was seen, although not clearly reported in a self-assessment disease-specific questionnaire.

Treatment of scoliosis in patients affected with Prader-Willi syndrome using various techniques.

BACKGROUND: The incidence of spinal deformity in children with Prader-Willi syndrome (PWS) is high, with 86% of these patients found to have a significant structural scoliosis; however, there are very few case reports describing surgical treatment for this deformity. METHODS: The authors reviewed a case series consisting of 6 patients who underwent spine surgery for scoliosis. Children's mean age at index surgery was 12 years and 10 months (range, 10 to 15 yrs). Clinical evaluation revealed the typical phenotypic features of the PWS in all of the patients; 4 subjects had a karyotype confirmation of PWS. Major structural curves showed preoperative mean Cobb angles of 80.8 degrees (range, 65 degrees to 96 degrees ). Hybrid instrumentation with sublaminar wires, hooks and screws was used in the first 2 patients, while the remaining 4 were treated with titanium pedicle screw constructs. RESULTS: The mean clinical and radiological follow-up was 3 years and 10 months (range, 2 years to 9 years). Major complication rate was 50%. One patient who developed a major intraoperative complication (paraparesis) prevented spinal fusion to be obtained: the neurologic deficit resolved completely after instrumentation removal. Solid arthrodesis and deformity correction in both coronal and sagittal plane was, however, achieved in the other 5 cases and no significant curve progression was observed at follow-up. Another major short-term complication was encountered 3 months after surgery in a patient who experienced the detachment of a distally located rod and required correction through revision surgery and caudal extension by one level. Cervico-thoracic kyphosis was seen in 1 patient who did not require revision surgery. CONCLUSIONS: Spine reconstructive surgery in patients with PWS is rare and highly demanding.The best method of reconstruction is posterior multilevel pedicle screw fixation. Moreover, even with modern techniques, the risk of complications is still high. These new techniques, however, have shown to improve the postoperative course by allowing for immediate mobilization without any brace or cast. The use of the growing rod techniques, requiring repeated surgeries, should be carefully evaluated in each single case.

Surgical treatment for scoliosis in Marfan syndrome.

STUDY DESIGN: Review of results of patients with Marfan syndrome treated with instrumented posterior fusion alone for scoliosis. OBJECTIVE: To analyze the results of surgical treatment for scoliosis in Marfan syndrome. SUMMARY OF BACKGROUND DATA: Few studies have been reported in the literature on surgical treatment for scoliosis in Marfan syndrome, analyzing long-term results of posterior instrumented fusion. METHODS: Twenty-three patients with Marfan syndrome with a mean age of 17 years (range, 11-31 years) were treated surgically from 1982 to 1995 for scoliosis, using a posterior instrumented fusion alone (Harrington rod with sublaminar wires in the first 16 cases, and a more recent hybrid instrumentation in the remaining 7 cases). All of the patients received a long posterior instrumented fusion, including 12.3 levels on average (range, 9-17), extending the fusion area to vertebrae that were neutral and stable in both coronal and sagittal planes before surgery. Patients were analyzed as two different groups (Group 1 and Group 2) according to the different posterior instrumentations employed: Group 1 included 16 patients treated by the Harrington distraction rod technique with sublaminar wires, while Group 2 included 7 patients treated using more recent hybrid instrumentations. Presentation features, complications, and results were analyzed. RESULTS: At a minimum follow-up of 7 years (maximum, 18 years), all 23 patients were reviewed. The mean age was 26.8 years (range, 20-38 years). The average preoperative scoliosis value of 69.91 degrees was initially corrected to 38.17 degrees, averaged 40.89 degrees 1 year after surgery, and was finally equal to 44.09 degrees at the last follow-up. Differences in terms of scoliosis correction achieved with different instrumentations (Groups 1 and 2) did not reach statistical significance. In Group 2 patients, the percentage of postoperative correction was slightly lower (44.23%) than that of Group 1 (46.55%) but remained more stable at the last follow-up (40.97% vs. 36.38% of Group 1). There were 11 complications in 10 of the 23 patients (43.4%); two complications occurred in 1 patient. Intraoperatively, dural tears occurred in 2 cases (8.6%). Pseudarthrosis with instrumentation failure in 2 cases (8.6%) required revision surgery. Five (21.7%) distal hook dislodgements with moderate loss of scoliosis correction, 1 (4.3%) mild loss of correction without instrumentation failure, and 1 asymptomatic cervicothoracic junctional kyphosis. did not require surgery. All complications occurred among the 16 Group 1 patients, treated using the Harrington rod instrumentation with sublaminar wires. CONCLUSIONS: These results seemed to demonstrate that a satisfactory stabilization of scoliosis can be achieved by posterior instrumentation alone in patients with Marfan syndrome. Instrumented posterior fusion should be extended to include vertebrae that are neutral and stable in both coronal and sagittal planes before surgery, in order to ensure stabilization of the deformity and reduce the risks of decompensation of the spine.