Abhay Rao

A survey of current controversies in scoliosis surgery in the United Kingdom.

Study Design. A 10-point questionnaire was constructed to identify the philosophy of surgeons on various aspects of scoliosis surgery, such as choice of implant, bone graft, autologous blood transfusion, cord monitoring, and computer-assisted surgery. Comparisons were then made with recommendations published in the spinal literature. Objective. To determine certain aspects of the current practice of scoliosis surgery in the United Kingdom. Summary of Background Data. Guidelines for good clinical practice in spinal deformity surgery are available in the United Kingdom but do not cover a number of controversial issues. Methods. Consultants and fellows attended the 2009 British Scoliosis Society meeting. Fifty questionnaires were completed by 45 consultants and 5 fellows. Results. All pedicle screw constructs favored by 25 of 50, hybrid 24 of 50 (1 undecided). Posterior construct of fewer than 10 levels, 20 of 50 would not cross-link, 11 of 50 used 1, and 19 of 20 used 2 or more. More than 10 levels 17 of 50 considered cross-links unnecessary, 4 of 50 used 1 and 29 of 50 used 2 or more. Eighty-eight percent preferred titanium alloy implants, whereas others used a mixture of stainless steel and cobalt chrome. When using bone graft, respondents used bone substitutes (24), iliac crest graft (14), allograft (12) and demineralized bone matrix (9) in addition to local bone. Ten of 50 would use recombinant bone morphogenetic protein (3 for revision cases only). Thirty-nine of 50 routinely used intraoperative cell salvage and 4 of 50 never used autologous blood. All used cord monitoring: sensory (19 of 50), motor (2 of 50), and combined (29 of 50). None used computer-aided surgery. Twenty-six operated alone, 12 operated in pairs, and 12 varied depending on type of case. Conclusion. This survey shows interesting variations in scoliosis surgery in the United Kingdom. It may reflect the conflicting evidence in the literature.

Retrieval of a migrated AxiaLIF lumbosacral screw using fluoroscopic guidance with simultaneous real-time sigmoidoscopy: technical report.

Study Design. Technical report. Objective. This article describes the technique of using intraoperative sigmoidoscopy as an adjunct for retrieval of the AxiaLIF lumbosacral screw after failure of lumbar fusion. Summary of Background Data. Minimally invasive axial lumbar interbody fusion devices have emerged during the past 3 years as an alternative to traditional surgery for the treatment of intractable back pain. No reports of inferior migration of the lumbosacral screw causing rectal symptoms have been previously described. A 32-year-old firefighter with intractable lumbar back pain was treated with minimally invasive axial lumbar interbody fusion with L4–S1 pedicle screw fixation. Sequential images obtained for more than 18 months demonstrated loosening and migration of the axial screw 3.5 cm inferiorly causing impression on the rectum and symptoms of tenesmus. Methods. Preoperative sigmoidoscopy was performed to exclude rectal perforation. During retrieval of the lumbosacral screw, simultaneous sigmoidoscopy was performed to ensure the rectum was not damaged. Results. The lumbosacral screw was successfully removed using a presacral approach. The patients rectal symptoms improved postoperatively, and was discharged after 48 hours. Conclusion. For the retrieval of migrated AxiaLIF lumbosacral screws, intraoperative sigmoidoscopy is technically feasible and serves as a useful adjunct to ensure the integrity of the rectal mucosa is maintained. This technique can be used to avoid the potential morbidity of rectal perforation, and subsequent laparotomy and defunctioning colostomy. Level of Evidence: N/A

Vertebral body versus iliac crest bone marrow as a source of multipotential stromal cells: Comparison of processing techniques, tri-lineage differentiation and application on a scaffold for spine fusion

The potential use of bone progenitors, multipotential stromal cells (MSCs) helping spine fusion is increasing, but convenient MSC sources and effective processing methods are critical factors yet to be optimised. The aim of this study was to test the effect of bone marrow processing on the MSC abundance and to compare the differentiation capabilities of vertebral body-bone marrow (VB-BM) MSCs versus iliac crest-bone marrow (IC-BM) MSCs. We assessed the effect of the red blood cell lysis (ammonium chloride, AC) and density-gradient centrifugation (Lymphoprep™, LMP), on the extracted VB-BM and IC-BM MSC numbers. The MSC abundance (indicated by colony counts and CD45lowCD271high cell numbers), phenotype, proliferation and tri-lineage differentiation of VB-BM MSCs were compared with donor-matched IC-BM MSCs. Importantly, the MSC attachment and osteogenesis were examined when VB-BM and IC-BM samples were loaded on a beta-tricalcium phosphate scaffold. In contrast to LMP, using AC yielded more colonies from IC-BM and VB-BM aspirates (p = 0.0019 & p = 0.0201 respectively). For IC-BM and VB-BM, the colony counts and CD45lowCD271high cell numbers were comparable (p = 0.5186, p = 0.2640 respectively). Furthermore, cultured VB-BM MSCs exhibited the same phenotype, proliferative and adipogenic potential, but a higher osteogenic and chondrogenic capabilities than IC-BM MSCs (p = 0.0010 and p = 0.0005 for calcium and glycosaminoglycan (GAG) levels, respectively). The gene expression data confirmed higher chondrogenesis for VB-BM MSCs than IC-BM MSCs, but osteogenic gene expression levels were comparable. When loaded on Vitoss™, both MSCs showed a similar degree of attachment and survival, but a better osteogenic ability was detected for VB-BM MSCs as measured by alkaline phosphatase activity (p = 0.0386). Collectively, the BM processing using AC had more MSC yield than using LMP. VB-BM MSCs have a comparable phenotype and proliferative capacity, but higher chondrogenesis and osteogenesis with or without using scaffold than donor-matched IC-BM MSCs. Given better accessibility, VB-BM could be an ideal MSC source for spinal bone fusion.

An NIHR-approved two-year observational study on magnetically controlled growth rods in the treatment of early onset scoliosis

Aims The primary aim of this study was to evaluate the performance and safety of magnetically controlled growth rods in the treatment of early onset scoliosis. Secondary aims were to evaluate the clinical outcome, the rate of further surgery, the rate of complications, and the durability of correction. Patients and Methods We undertook an observational prospective cohort study of children with early onset scoliosis, who were recruited over a one‐year period and followed up for a minimum of two years. Magnetically controlled rods were introduced in a standardized manner with distractions performed three‐monthly thereafter. Adverse events which were both related and unrelated to the device were recorded. Ten children, for whom relevant key data points (such as demographic information, growth parameters, Cobb angles, and functional outcomes) were available, were recruited and followed up over the period of the study. There were five boys and five girls. Their mean age was 6.2 years (2.5 to 10). Results The mean coronal Cobb angle improved from 57.6° (40° to 81°) preoperatively, 32.8° (28° to 46°) postoperatively, and 41° (19° to 57°) at two years. Five children had an adverse event, with four requiring return to theatre, but none were related to the device. There were no neurological complications or infections. No devices failed. One child developed a proximal junctional kyphosis. The mean gain in spinal column height from T1 to S1 was 45.4 mm (24 to 81) over the period of the study. Conclusion Magnetically controlled growth rods provide an alternative solution to traditional growing rods in the surgical management of children with early onset scoliosis, supporting growth of the spine while controlling curve progression. Their use has clear psychosocial and economic benefits, with the reduction of the need for repeat surgery as required with traditional growing rods.

Benefits of the use of blood conservation in scoliosis surgery

AIM To investigate whether autologous blood transfusion (ABT) drains and intra-operative cell salvage reduced donor blood transfusion requirements during scoliosis surgery. METHODS Retrospective data collection on transfusion requirements of patients undergoing scoliosis surgery is between January 2006 and March 2010. There were three distinct phases of transfusion practice over this time: Group A received “traditional treatment” with allogeneic red cell transfusion (ARCT) in response to an intra- or post-operative anaemia (Hb < 8 g/dL or a symptomatic anaemia); Group B received intra-operative cell salvage in addition to “traditional treatment”. In group C, ABT wound drains were used together with both intra-operative cell salvage and “traditional treatment”. RESULTS Data from 97 procedures on 77 patients, there was no difference in mean preoperative haemoglobin levels between the groups (A: 13.1 g/dL; B: 13.49 g/dL; C: 13.66 g/dL). Allogeneic red cell transfusion was required for 22 of the 37 procedures (59%) in group A, 17 of 30 (57%) in group B and 16 of 30 (53%) in group C. There was an overall 6% reduction in the proportion of patients requiring an ARCT between groups A and C but this was not statistically significant (χ2 = 0.398). Patients in group C received fewer units (mean 2.19) than group B (mean 2.94) (P = 0.984) and significantly fewer than those in group A (mean 3.82) (P = 0.0322). Mean length of inpatient stay was lower in group C (8.65 d) than in groups B (12.83) or A (12.62). CONCLUSION When used alongside measures to minimise blood loss during surgery, ABT drains and intra-operative cell salvage leads to a reduced need for donor blood transfusion in patients undergoing scoliosis surgery.

En bloc resection of a thoracic chordoma is possible using minimally invasive anterior access: An 8-year follow-up

Thoracic spine chordomas are a rare clinical entity and present several diagnostic and management challenges. Posterior debulking techniques are the traditional approach for the resection of thoracic tumors involving the vertebral body. Anterior approaches to the thoracic spine enable complete tumor resection and interbody fusion. However, this approach has previously required a thoracotomy incision, which is associated with significant perioperative morbidity, pain, and the potential for compromised ventilation and subsequent respiratory sequelae. The extreme lateral approach to the anterior spine has been used to treat degenerative disorders of the lower thoracic and lumbar spine, and reduces the potential complications compared with the anterior transperitoneal/transpleural approach. However, such an approach has not been utilized in the treatment of thoracic chordomas. We describe the first case of an en bloc resection of a thoracic chordoma via a minimally invasive eXtreme lateral interbody fusion approach.

Surgical Technique of Vertebral Cement Augmentation (Vertebro/Kyphoplasty)

The debilitating nature of pain after vertebral compression fracture both due to osteoporosis and metastatic disease is well documented in the literature. Vertebroplasty and kyphoplasty are two techniques for augmenting of vertebral bodies with acrylic bone cement. The aim of the procedure is to stabilize the vertebral fracture and thus relieve pain. A biopsy may be carried out at the time of cement augmentation. It is generally done as a day case procedure.

Spinal Stenosis/Decompression

Spinal stenosis. Disc prolapse with no relative spinal instability. Caudal equina syndrome.

Surgical Technique of Anterior Cervical Discectomy and Fusion (ACDF)

ACDF has gained wide acceptance in the management of refractory symptoms attributed to cervical intervertebral disc disease. The aim of the procedure is to remove the intervertebral disc and variable amounts of bony osteophytes and the posterior longitudinal ligament (PLL) thus ensuring adequate decompression of the spinal cord and nerve roots.

An Accurate Method Of Bone Graft Application In Spinal Surgery

B one grafting is a commonly used technique in orthopaedic surgery. In posterior spinal surgery, accurate placement of postero-lateral bone graft is important in achieving solid bony fusion. This can be difficult and messy due to the overlying muscles and bulky implants when applied manually. We have devised a simple and effective method of bone graft application for posterior spinal surgery. The nozzle end of a standard 10ml syringe is removed (Figure 1). The syringe is then packed full of bone graft and compacted (Figure 2 & 3). We routinely use an autograft and synthetic bone substitute mixture. The compacted graft can be accurately applied by placing the cut syringe end at the desired site and depressing the syringe plunger. This method is more accurate than manual application of bone graft by hand. This method is used routinely at our institution for spinal fusion and is being applied to other orthopaedic procedures requiring bone grafting.