To assess radiological fusion rates in posterolateral fusions using SiS-CaP. Retrospective, radiological follow-up study. Single surgeon series of 76 consecutive patients were evaluated, in a regional spinal unit. All patients had clinical and radiological (MRI) spinal canal stenosis secondary to degenerative spondylosis or spondylolisthesis. Surgery consisted of instrumentation, decompression and meticulous preparation of the posterolateral graft bed by removal of all soft tissues posterior to the inter-transverse membrane and decortication of transverse processes (TPs). SiS-CaP putty was injected into this gutter and moulded around the instrumentation. Good quality, well prepared bone chips from the posterior decompression were seeded into the putty. Patient radiographs were reviewed at 3-6 months, 1 year and 2 years. Radiographs were assessed using a protocol to examine granularity, bone formation and evidence of pseudarthrosis, based upon previously reported literature . 1. and our personal experience. Of the 76 patients, 26 were excluded. M:F was 21:29. Mean age was 58yrs. Average number of motion segments fused per case was 2.2. There was one pseudarthrosis with metalwork fracture, and thus a total fusion rate of 98%. In addition, one patient had scanty bridging of TPs, and one patient had lucency around the S1 screws. SiS-CaP, as a bone graft substitute in posterolateral instrumented fusions, gives comparable results to published fusion rates using autologous iliac crest grafting and/or Bone Morphogenic Protein . 2. Moreover, it avoids the associated morbidity of iliac bone harvest

Aims

To report the surgical outcome of patients with severe Scheuermann’s kyphosis treated using a consistent technique and perioperative management.

Study Design. Single surgeon prospective cohort with radiological follow-up. Background. Anjarwalla et al. have shown that the addition of posterior pedicle supplementation without posterolateral fusion during an ALIF procedure significantly increases the rate of interbody fusion when using a carbon fibre / PEEK cage packed with autogenous iliac crest graft. Stand alone ALIF cages which utilise screws passing through the interbody cage and into the vertebral bodies were designed to obviate the need for a posterior procedure by increasing the anterior construct stability and fusion rate. Objective. To assess the effect of posterior pedicle screw supplementation without posterolateral fusion on the fusion rate of ALIF when using anterior cage and screw constructs. Method. Between 2003 and 2008 91 patients underwent ALIF procedure under a single surgeon for low back pain associated with degenerative disc disease or lytic spondylolisthesis. Routine CT was performed at around 1 to 2 years follow up to ensure union prior to discharge. It was noted that there was a significant number of locked pseudathroses, especially in 2 level cases, and in 2006 the surgeon started to perform simultaneous supplementary posterior pedicle screw stabilisation without posterolateral fusion in the majority of cases. Results. Of the 91 patients, 77 (85%) had CT follow up at mean 21 months. 45 patients had anterior surgery alone (26 single level and 19 two level) and 32 had front back surgery (15 single level and 17 two level). Pseudarthrosis was seen in 16 patients (36%) of the anterior alone group and 2 (6%) of the front back group. In the anterior alone group, pseudarthosis occurred in 6 / 26 (23%) patients with single level surgery and 10 /19 (53%) of those with two level surgery. In this last group, the pseudarthosis occurred in the upper fusion level in five patients and at both fusion levels in other five. Conclusion. Posterior pedicle screw supplementation without posterolateral fusion improves the fusion rate of ALIF when using anterior cage and screw constructs. We would recommend supplementary posterior fixation especially in cases where more than one level is being operated

Purpose of the study. Two patients with very severe thoracolumbar Scheuermann's kyphosis who developed spontaneous bony fusion across the apex of the deformity are presented and their treatment, as well as surgical outcome is discussed. Summary of Background Data. Considerable debate exists regarding the pathogenesis, natural history and treatment of Scheuermann's kyphosis. Surgical correction is indicated in the presence of severe kyphosis which carries the risk of neurological complications, persistent back pain and significant cosmetic deformity. Methods. We reviewed the medical notes and radiographs of 2 adolescent patients with severe thoracolumbar Scheuermann's kyphosis who developed spontaneous posterior and anteroposterior fusion across the apex of the deformity. Results. Patient 1. A male patient aged 17 years and 11 months underwent kyphosis correction when the deformity measured 115o and only corrected to 100o on supine hyperextension radiograph against the bolster; he had a small associated scoliosis. The surgery involved a combined single-stage anterior and posterior spinal arthrodesis T4-L3 with the use of posterior pedicle hook/screw/rod instrumentation and autologous rib graft. The anterior longitudinal ligament was ossified from T10 to L1 with bridging osteophytes extending circumferentially from T11 to T12 at the apex of kyphosis and displacing the major vessels anteriorly. The intervertebral discs from T9 to T12 were very stenotic and immobile. The osteophytes were excised both on the convexity and concavity of the associated thoracolumbar scoliosis. The anterior longitudinal ligament was released and complete discectomies back to the posterior longitudinal ligament were performed from T7 to L1. During the posterior exposure, the spine was found to be spontaneously fused across the apex of the kyphosis from T9 to L1. There were no congenital vertebral anomalies. Extensive posterior apical closing wedge osteotomies were performed from T7 to T12. The fused facets and ossified ligamentum flavum were excised and the spine was mobilised at completion of the anterior and posterior osteotomies. The kyphosis was corrected using a cantilever maneuver from proximal to distal under spinal cord monitoring. Excellent correction to 58o was achieved and maintained at follow-up. Autologous rib graft was used to enhance a solid bony fusion. Patient 2. A female patient aged 18 years and one month underwent kyphosis correction when the deformity measured 115o and only corrected to 86o on supine hyperextension radiograph against the bolster; she had a small thoracolumbar scoliosis. The surgery involved a single-stage posterior spinal arthrodesis T2-L4 with the use of posterior pedicle hook/screw/rod instrumentation and autologous iliac crest bone. The spine was spontaneously fused across the apex of kyphosis from T9 to L1. There were no congenital vertebral anomalies. Extensive posterior apical closing wedge osteotomies were performed from T6 to T12. The fused facets and ossified ligamentum flavum were excised and the spine was mobilised at completion of the osteotomies. The kyphosis was corrected using a cantilever maneuver from proximal to distal under spinal cord monitoring. Excellent correction to 60o was achieved and maintained at follow-up. Autologous iliac crest graft was used to achieve a solid bony fusion. In both patients the preoperative MRI assessed the intraspinal structures but failed to diagnose the solid fusion across the posterior bony elements at the apex of kyphosis. A CT scan with 3D reconstruction would have illustrated the bony anatomy across the kyphosis giving valuable information to assist surgical planning. This is recommended in the presence of rigid thoracolumbar Scheuermann's kyphosis which does not correct in hyperextension, especially if the plain radiograph shows anterior bridging osteophytes. Conclusion. Spontaneous posterior or anteroposterior fusion can occur across the apex of severe thoracolumbar Scheuermann's kyphosis; this should be taken into account when surgical correction is anticipated. The bony ankylosis may represent the natural history of an extreme deformity as an attempt of the spine to auto-stabilise. A combination of factors including a rigid deformity, which limits significantly active movement of the spine, as well as anterior vertebral body wedging with severe adjacent disc stenosis which induces bridging osteophyte formation may result in the development of spontaneous fusion across the apex of the kyphosis either posteriorly or anteroposteriorly. In the presence of an isolated posterior fusion, segmental posterior closing wedge osteotomies with complete excision of the ossified ligamentum flavum and fused facets should mobilise the thoracolumbar spine and allow for kyphosis correction. An additional anterior spinal release including complete discectomies, resection of the anterior longitudinal ligament and osteophytes is required if the bony fusion extends anteroposteriorly. Patients with Scheuermann's kyphosis should be ideally treated at an earlier stage and with a lesser degree of deformity so that this ossification process is prevented

There are few reports on the treatment of pyogenic lumbar spondylodiscitis through the posterior approach using a single incision. Between October 1999 and March 2003 we operated on 18 patients with pyogenic lumbar spondylodiscitis. All underwent posterior lumbar interbody fusion using an autogenous bone graft from the iliac crest and pedicle screws via a posterior approach. The clinical outcome was assessed using the Frankel neurological classification and the criteria of Kirkaldy-Willis. Under the Frankel classification, two patients improved by two grades (C to E), 11 by one grade, and five showed no change. The Kirkaldy-Willis functional outcome was excellent in five patients, good in ten and fair in three. Bony union was confirmed six months after surgery in 17 patients, but in one patient this was not achieved until two years after operation. The mean lordotic angle before operation was 20° (−2° to 42°) and the mean lordotic angle at the final follow-up was 32.5° (17° to 44°). Two patients had a superficial wound infection and two a transient root injury. Posterior lumbar interbody fusion with an autogenous iliac crest bone graft and pedicle screw fixation via a posterior approach can provide satisfactory results in pyogenic spondylodiscitis.

Aims

We reviewed 34 consecutive patients (18 female-16 male) with isthmic spondylolysis and grade I to II lumbosacral spondylolisthesis who underwent in situ posterolateral arthodesis between the L5 transverse processes and the sacral ala with the use of iliac crest autograft. Ten patients had an associated scoliosis which required surgical correction at a later stage only in two patients with idiopathic curves unrelated to the spondylolisthesis.

We reviewed 212 consecutive patients with adolescent idiopathic scoliosis who underwent posterior spinal arthrodesis using all pedicle screw instrumentation in terms of clinical, radiological and Scoliosis Research Society (SRS)-22 outcomes. In Group 1 (51 patients), the correction was performed over two rods using bilateral segmental pedicle screws. In Group 2 (161 patients), the correction was performed over one rod using unilateral segmental pedicle screws with the second ^{rod providing stability of the construct through two-level screw fixation at proximal and distal ends. The mean age at surgery was 14.8 years in both groups. Comparison between groups showed no significant differences with regard to age and Risser grade at surgery, pre- and post-operative scoliosis angle, coronal Cobb correction, length of hospital stay and SRS scores. Correction of upper thoracic curves was significantly better in Group 1 (p = 0.02). Increased surgical time and intra-operative blood loss was recorded in Group 1 (p < 0.001 and p = 0.04, respectively). The implant cost was reduced by mean 35% in Group 2 due to the lesser number of pedicle screws.}

Unilateral and bilateral pedicle screw techniques have both achieved excellent deformity correction in adolescent patients with idiopathic scoliosis, which was maintained at two-year follow-up. This has been associated with high patient satisfaction and low complication rates.