Long-term outcome after surgical treatment of Scheuermann's Kyphosis (SK).

STUDY DESIGN: A retrospective observational cohort study with a minimum follow-up of 10 years of patients who underwent surgery for Scheurmann Kyphosis (SK). OBJECTIVE: Evaluate the long-term clinical and radiological outcome of patients with SK who either underwent combined anterior-posterior surgery or posterior instrumented fusion alone. There is paucity of literature for long-term outcome studies on SK. The current trend is towards only posterior (PSF) surgical correction for SK. The combined strategy of anterior release, fusion and posterior spinal fusion (AF/PSF) for kyphosis correction has become historic relic. Long-term outcome studies comparing the two procedures are lacking in literature. METHODS: 51 patients (30 M: 21F) who underwent surgery for SK at a single centre were reviewed. Nineteen had posterior instrumentation alone (PSF) (Group 1) and 32 underwent combined anterior release, fusion with posterior instrumentation (AF/PSF) (Group 2). The clinical data included age at surgery, gender, flexibility of spine, instrumented spinal levels, use of cages and morcellised rib grafts (in cases where anterior release was done), posterior osteotomies and instrumentation, complications and indications for revision surgery. Preoperative flexibility was determined by hyperextension radiographs. The radiological indices were evaluated in the pre-operative, 2-year post-operative and final follow-up [Thoracic Kyphosis (TK), Lumbar lordosis (LL), Voustinas index (VI), Sacral inclination (SI) and Sagittal vertical axis (SVA)]. The loss of correction and incidence of JK (Junctional Kyphosis) and its relation to fusion levels were assessed. Complications and difference in outcome between the two groups were analyzed. RESULTS: The mean age at surgery for 51 patients was 20.6 years who were followed up for a minimum of 10 years (mean: 14 years; range 10-16 years). The mean age was 18.5 ± 2.2 years and 21.9 ± 4.8 years in groups 1 and 2, respectively. The mean pre- and 2-year post-operative ODIs were 32.6 ± 12.8 and 8.4 ± 5.4, respectively, in group 1 (p < 0.0001) and 30.7 ± 11.7 and 6.4 ± 5.7, respectively, in group 2 (p < 0.0001). The final SRS-22 scores in group 1 and 2 were 4.1 ± 0.4 and 4.0 ± 0.35, respectively (p = 0.88). The preoperative flexibility index was 49.2 ± 4.2 and 43 ± 5.6 in groups 1 and 2, respectively (p < 0.0001). The mean TKs were 81.4° ± 3.8° and 86.1° ± 6.0° for groups 1 and 2, respectively, which corrected to 45.1° ± 2.6° and 47.3° ± 4.8°, respectively, at final follow-up (p < 0.0001). The mean pre-operative LL angle was 60.0° ± 5.0° and 62.4° ± 7.6° in groups 1 and 2, respectively, which at final follow-up was 45.1° ± 4.4° and 48.1° ± 4.8°, respectively (p < 0.0001). The mean pre-operative and final follow-up Voustinas index (VI) in group 1 were 22.9 ± 2.9 and 11.2 ± 1.2, respectively, and in group 2 was 25.9 ± 3.5 and 14.0 ± 2.3, respectively. The mean pre-operative and final follow-up SI angle were 43.6° ± 3.3° and 31.2° ± 2.5° in group 1, respectively, and 44.3° ± 3.5° and 32.1° ± 3.5° in group 2, respectively (p < 0.0001). The pre-operative and final follow-up SVA in group 1 were - 3.3 ± 1.0 cms and - 1.3 ± 0.5 cms, respectively, and in group 2 was - 4.0 ± 1.3cms and - 1.9 ± 1.1cms, respectively (p < 0.0001). Though the magnitude of curve correction in the groups 1 and 2 was significant 36° vs 39° (p = 0.05), there was no significant difference in correction between the two groups. Proximal JK was seen in seven and distal JK in five patients were observed in the whole cohort. CONCLUSION: The long-term clinical outcomes for both PSF and AF/PSF are comparable with reproducible results. No difference was noted in loss of correction and outcome scores between the two groups. The correction of thoracic kyphosis (TK) had a good correlation with ODI. AF/PSF had much higher complications than PSF group. The objective of correcting the sagittal profile and balancing the whole spinal segment on the pelvis can be achieved through single posterior approach with fewer complications.

Calcified giant thoracic disc herniations: considerations and treatment strategies.

INTRODUCTION: Giant herniated thoracic discs (GHTD) remain a surgical challenge. When combined with calcification, these discs require altered surgical strategies and have only been infrequently described. Our objective was to describe our surgical approaches in the management of calcified GHTD. METHODS: This was a retrospective cohort study of all patients with calcified GHTD operated between 2004 and 2012. Data were collected from review of patients' notes and radiographs and included basic demographic and radiological data, clinical presentation and outcome, operative procedure and complications. RESULTS: During the study period, there were 13 patients with calcified GHTD, including 6 males and 7 females (mean age 55 years, range 31-83 years). The average canal encroachment was 62% (range 40-90%); mean follow-up 37 months (12-98). All patients were treated with anterior thoracotomy, varying degrees of vertebral resection, removal of calcified disc and with or without reconstruction. The average time for surgery was 344 min (range 212-601 min) and estimated blood loss 1,230 ml (range 350-3,000 ml). Post-operatively, 8 patients improved by 1 Frankel grade (62%), 2 improved by 2 grades (15%) and 3 did not change their grade (23%). The complication rate was 4/13 (31%; 3 patients with durotomies (2 incidental, 1 intentional) and 1 with recurrence). DISCUSSION: Calcified GHTD remain a surgical challenge. Anterior decompression through a thoracotomy approach, and varying degrees of vertebral resection with or without reconstruction allowed us to safely remove the calcified fragment. All patients remained the same (23%) or improved by at least 1 grade (77%) neurologically, without radiographic failure at final follow-up.

Surgical correction of scoliosis in Rett syndrome: cord monitoring and complications.

AIM: Rett syndrome is a progressive neurodevelopmental disorder that predominantly affects females and is associated with a high incidence of scoliosis and epilepsy. There is scant published work about intraoperative spinal cord monitoring in these patients and little more regarding the rate of perioperative complications. We investigated our institutions' experience with both. METHODS: We retrospectively reviewed the records of 11 patients with Rett syndrome who underwent surgical correction of scoliosis at our institution between 2004 and 2010. RESULTS: Eleven patients underwent successful correction of their scoliosis at an average age of 12. Eight of the patients suffered one or more significant complications. The average curve was corrected from 71° to 27°. Successful spinal cord monitoring was achieved in eight of the nine patients where it was attempted. No patient suffered any neurological complications. Average inpatient stay was 18.2 days. CONCLUSION: Scoliosis surgery in patients with Rett syndrome carries a very high rate of complications and an average hospital stay approaching 3 weeks. Both caregivers and surgeons should be aware of this when planning any intervention. These patients frequently have useful lower limb function and spinal cord monitoring is a valid tool to aid in its preservation. We would suggest aggressive optimisation of these patients prior to surgery, with an emphasis on nutrition.

Scoliosis in Duchenne's muscular dystrophy: a changing trend in surgical management : a historical surgical outcome study comparing sublaminar, hybrid and pedicle screw instrumentation systems.

A non-randomised retrospective study to compare the results of surgical correction of scoliosis in Duchenne's muscular dystrophy (DMD) patients using three different instrumentation systems-Sublaminar instrumentation system (Group A), a hybrid of sublaminar and pedicle screw systems (Group B) and pedicle screw system alone (Group C). Between 1993 and 2003, 43 patients with DMD underwent posterior spinal fusion and instrumentation. Group A (n = 19) had sublaminar instrumentation system, Group B (n = 13) had a hybrid construct and Group C (n = 11) was treated with pedicle system. The mean blood loss in Group A was 4.1 l, 3.2 l in Group B and 2.5 l in Group C. Average operating times in Group A, B and C were 300, 274 and 234 min, respectively. Mean pre-operative, post-operative and final Cobb angle in Group A was 50.05 +/- 15.46 degrees , 15.68 +/- 11.23 degrees and 21.57 +/- 11.63 degrees , Group B was 17.76 +/- 8.50 degrees , 3.61 +/- 2.53 degrees and 6.69 +/- 4.19 degrees and Group C was 25.81 +/- 9.94 degrees , 5.45 +/- 3.88 degrees , 8.90 +/- 5.82 degrees , respectively. Flexibility index or the potential correction calculated from bending radiographs were 60 +/- 6.33, 70 +/- 4.65 and 67 +/- 6.79% for Group A, Group B and Group C respectively. The percentage correction achieved was 72.5 +/- 14.5% in Group A, 82 +/- 6% in Group B and 82 +/- 8% in Group C. The difference between percentage correction achieved and the flexibility index was 12.45 +/- 8.22, 12.05 +/- 1.3 and 15.00 +/- 1.21% in Group A, B and C, respectively The percentage loss of correction in Cobb angles at final follow-up in Group A, B and C was 12.5 +/- 3.5, 16.5 +/- 1. and 12.5 +/- 2.5%, respectively. Complications seen in Group A were three cases of wound infection and two cases of implant failure; Group B had a single case of implant failure and Group C had one patient with wound infection and one case with a partial screw pull out. Early surgery and smaller curve corrections appears to be the current trend in the management of scoliosis in DMD. This has been possible due to early curve detection and surgery thus having the advantage of less post-operative respiratory complications and stay in paediatric intensive care. Also, early surgery avoids development of pelvic deformity and extension of instrumentation to the pelvis thereby reducing blood loss. This trend reflects the advent of newer and safer instrumentation systems, advanced techniques in anaesthesia and cord monitoring. Sublaminar instrumentation system group had increased operating times and blood loss compared to both the hybrid and pedicle screw instrumentation systems due to increased bleeding from epidural vessels and pelvic instrumentation. Overall, the three instrumentation constructs appear to provide and maintain an optimal degree of correction at medium to long term follow up but the advantages of lesser blood loss and surgical time without the need for pelvic fixation seem to swing the verdict in favour of the pedicle screw system.

Do anterior interbody cages have a potential value in comparison to autogenous rib graft in the surgical management of Scheuermann's kyphosis?

BACKGROUND CONTEXT: Previous studies have analyzed the outcome following posterior correction and combined anterior-posterior correction for Scheuermann's kyphosis. Traditionally interbody fusion has been obtained using morselized rib graft. Recently the use of titanium anterior cages has been suggested for interbody use. There are no long-term studies comparing these two techniques. PURPOSE: To investigate the potential value of titanium anterior interbody cages compared with morselized rib graft for anterior interbody fusion in combination with posterior instrumentation, correction, and fusion for Scheuermann's kyphosis. STUDY DESIGN: Nonrandomized comparison of two surgical techniques in matched subjects. PATIENT SAMPLE: Fifteen patients with identical preoperative radiographic and physical variables (age, gender, height, weight, body mass index) were managed with combined anterior release, interbody fusion, posterior instrumentation, correction, and fusion. Group A (n=8) had morselized rib graft inserted into each intervertebral disc space. Group B (n=7) had titanium interbody cages packed with bone graft inserted at each level. The posterior instrumentation extended from T2 to L2 in both groups. OUTCOME MEASURES: Preoperative and postoperative curve morphometry was studied on plain radiographs by two independent observers. The indices studied included Cobb angle, Ferguson's angle, Voutsinas index, sagittal vertical axis (SVA), sacral inclination (SI), and lumbar lordosis (LL). Interbody fusion was assessed at final follow-up. Each patient was reviewed at 3, 6, 12, 24, 48, and 60 months after surgery with standing radiographs. METHODS: Both surgical groups were compared in terms of radiological parameters and complications. Wilcoxon-matched pairs test and Mann-Whitney test were used. RESULTS: The average follow-up for Group A was 70 months and for Group B 66 months. For the whole group, the preoperative median Cobb angle for thoracic kyphosis was 86 degrees , the median Ferguson angle was 50 degrees , Voutsinas index was 28.7, SVA -3.5 centimeters, lumbar lordosis was 66 degrees , and the median sacral inclination angle was 40 degrees . The median postoperative Cobb angle was 42 degrees , Ferguson angle 28.4 degrees , Voutsinas index 13, SVA -4.0 centimeters, and the median sacral inclination angle was 34 degrees . There were significant differences between preoperative and postoperative measurements for all variables (p<.01), indicating that good correction was achieved. At 4-year follow-up, fusion criteria were satisfied in 12 of 15 cases (80%). Three patients had distal junctional kyphosis. There was no significant difference obtained in the final Cobb angle, Ferguson angle, and Voutsinas index when Group A (rib graft) was compared with Group B (titanium cage) Both Group A and B patients retained the postoperative correction achieved with respect to all the radiographic parameters studied. CONCLUSION: We were unable to demonstrate any significant advantage for the use of anterior titanium interbody cages over the use of morselized rib graft in the surgical management of Scheuermann's kyphosis. Given the not inconsiderable cost and the need for posterior chevron osteotomies when interbody cages are used, we have now reverted to our previous practice of using morselized rib graft at each intervertebral level.

Reduction of severe adolescent isthmic spondylolisthesis: a new technique.

STUDY DESIGN: The case of a 14-year-old boy with a severe-grade isthmic spondylolisthesis who underwent reduction and stabilization using this technique is described. OBJECTIVE: To report a new sequential 3-stage procedure for reduction and stabilization of severe adolescent isthmic spondylolisthesis during 1 operative session. SUMMARY OF BACKGROUND DATA: Conventional reduction techniques do not address the important regional anatomic restraints on the L5 nerve root during the reduction maneuver, thereby leading to a high risk of neurologic deficit. Using certain technical refinements could reduce the risk of neurologic deficit. A literature review of reduction of high-grade spondylolisthesis and details of the technique are presented. METHODS: We describe a new 3-stage procedure in a 14-year-old boy who presented with persistent mechanical low back pain, bilateral buttock and leg pain secondary to a severe-grade L5/S1 isthmic spondylolisthesis. Radiologic investigations, including plain radiographs and computerized tomography confirmed the diagnosis. Magnetic resonance imaging showed reduction of signal intensity in the disc at the L5/S1 level. We describe the 3 stages of this technique, which can provide complete sagittal correction. The technical variations to allow a safe reduction of the spondylolisthesis are illustrated. RESULTS: This new procedure can achieve almost complete reduction of severe grades of L5/S1 spondylolisthesis, leading to an excellent cosmetic result and also considerably reduces the risk of neurologic deficit. CONCLUSIONS: In severe-grade lumbosacral spondylolisthesis, isolated posterior fusion, even when supplemented with internal fixation, is not sufficient to prevent deformity progression. Therefore, a combined anterior and posterior fusion is necessary. Reduction of the deformity leads to restoration of normal sagittal alignment with an excellent cosmetic result. Reduction without release of posterior structures may lead to neurologic deficit. This 3-stage shortening procedure can provide sudden reduction of deformity with minimal risk of neurologic deficit. The procedure is technically demanding, and should be performed by spinal surgeons who are familiar with the principles of anterior and posterior fusions.

Results of hemivertebrectomy and fusion for symptomatic thoracic disc herniation.

We retrospectively analysed ten consecutive patients (age range 32-77 years) treated surgically from 1994 to 1999 for symptomatic thoracic disc herniation between the 6th and 12th thoracic discs. Clinically, eight patients had varying grades of back pain and eight patients had paraparesis. Radiography showed calcification in 50% of the herniated discs. Two patients had two-level thoracic disc herniation. Hemivertebrectomy followed by discectomy and fusion was carried out in all patients. Instrumentation with cages was performed in eight patients and bone grafting alone in two patients. The average follow-up was 24 months (range 13-36 months). Six patients had an excellent or good outcome, three had a fair outcome and one had a poor outcome. One patient had atelectasis, which recovered within 2 days of surgery. Another patient had developed complete paraplegia, detected at surgery by SSEPs, and underwent resurgery following magnetic resonance (MR) scan with complete corpectomy and instrumented fusion. At 2 years, she had a functional recovery. The patient with poor outcome had undergone a previous discectomy at T9/10. He developed severe back pain and generalised hyper-reflexia following corpectomy and fusion for disc herniation at T10/11. We advocate anterior transthoracic discectomy following partial corpectomy for symptomatic thoracic disc herniation between the 6th and 12th thoracic discs. This procedure offers improved access to the thoracic disc for an instrumented fusion, which is likely to decrease the risk of iatrogenic injury to the spinal cord.

Combined monitoring of motor and somatosensory evoked potentials in orthopaedic spinal surgery.

OBJECTIVES: To demonstrate possible advantages of combined (motor and sensory) versus single modality (either motor or sensory) intra-operative spinal cord monitoring and to investigate risk factors for post-operative neurological sequelae. METHODS: Recordings of lower limb motor evoked potentials (MEPs) to multi-pulse transcranial electrical stimulation (TES), and tibial nerve somatosensory evoked potentials (SEPs), were attempted during 126 operations in 97 patients (79 with spinal deformity and 18 with miscellaneous spinal disorders). RESULTS: Combined motor and sensory monitoring was successfully achieved in 104 of 126 (82%) operations. No response to either modality could be recorded in two patients with Friedreich' s ataxia. In 18 patients monitoring was possible in only one modality: SEPs could not be recorded in two patients and MEPs in 16. Significant intra-operative EP changes occurred in one or both modalities in 16 patients; in association with instrumentation in 10 cases, and with systemic changes in 6. After appropriate remedial measures, SEPs recovered either fully or partially in 8/8 patients and MEPs in only 67% (10/15 patients). New deficits were present post-operatively in 6 of the 16 patients with abnormal intra-operative EPs. Normal MEPs at the end of the operation correctly predicted the absence of new motor deficits in all cases. SEPs either remained unchanged or recovered fully after remedial measures in 3 patients with new post-operative motor deficits. Neurological complications were more frequent in patients with miscellaneous spinal disorders and/or pre-existing neurological deficits. No complications occurred in patients with idiopathic scoliosis. CONCLUSIONS: Combined SEPs and multi-pulse TES-MEPs provide a safe, reliable and sensitive method of monitoring spinal cord function in orthopaedic surgery. This method is superior to single modality techniques, both for increasing the number of patients in whom satisfactory monitoring of spinal cord function can be achieved and, for improving the sensitivity and predictivity of monitoring. Combined SEP/MEP methods may enhance the impact of neuromonitoring on the intra-operative management of the patient and favourably influence neurological outcome.