Magnet Fracture within a Magnetically Controlled Growing Rod: A Case Report of a New Mechanism of Failure.

INTRODUCTION: Magnetically controlled growing rods (MCGRs) have been widely adopted in the management of early-onset scoliosis since they were first described in 2012. Recent reports have highlighted concerns around their safety. To date, little is understood about the risk factors and modes of failure in these devices. CASE REPORT: We report a novel mechanism of device failure in a 14-year-old patient following multiple revisions of MCGRs.Clinically, there was no evidence of device failure and the MCGRs appeared radiologically intact. Explantation analysis revealed multiple compromised/non-functional components. A previously undocumented phenomenon of complete magnet fracture was also seen. CONCLUSION: The absence of clinical or radiological features of device failure in this case makes the findings of great concern. Given the relative paucity of high-quality evidence surrounding the use of MCGRs, we support calls for urgent comparative studies and further investigation of risk factors for device failure.

Multiple injections for low back pain: What's the future?

AIMS: To examine the strength of evidence available for multiple facet joint injections (FJIs) and medial branch blocks (MBBs), and to report on the variations in the NHS England framework using the getting it right first time (GIRFT) data. METHODS: Systematic review using patient, intervention, comparison, outcome and study strategy. The literature search using Cochrane, MEDLINE and EMBASE databases using MeSH terms: lumbar spine, spinal injection and facet joint ("Appendix A"). RESULTS: Three studies were identified that investigated the efficacy of multiple FJIs or MBBs. None of these studies reported sustained positive outcomes at long-term follow-up. CONCLUSION: There is a paucity of levels I and II evidence available for the efficacy of multiple FJIs and MBBs in treating low back pain. GIRFT data show a high degree of variation in the use of multiple FJIs, which would not be supported by the literature. These slides can be retrieved under Electronic Supplementary Material.

Retroperitoneal haematoma in a postoperative ALIF patient taking rivaroxaban for atrial fibrillation.

BACKGROUND: Novel oral anticoagulants (NOACs) are being increasingly used in the secondary prevention of thromboembolic stroke in patients with atrial fibrillation. Patients taking NOACs are difficult to manage perioperatively, and several unexpected complications have been reported in these patients. CASE REPORT: We report a case of a rivaroxaban-induced retroperitoneal haematoma in a 72-year-old man who underwent an L5/S1 anterior lumbar interbody fusion (ALIF) for grade 1 spondylolytic spondylolisthesis. The patient suffered from atrial fibrillation and was taking rivaroxaban, a factor Xa inhibitor, for thromboembolic risk reduction. In accordance with perioperative Novel Oral Anticoagulant (NOAC) guidelines, rivaroxaban was stopped 2 days preoperatively and restarted on the third postoperative day. The patient presented on the ninth postoperative day, complaining of severe left iliac fossa pain, nausea, and vomiting, accompanied by swelling and bruising around the surgical site. A computed tomography (CT) scan showed a large expanding retroperitoneal haematoma. The patient was taken back to theatre for an evacuation of the haematoma and subsequently recovered without any further complications. CONCLUSION: This is the first case of a rivaroxaban-induced retroperitoneal haematoma reported in the literature, secondary to elective spinal surgery. This report adds to the body of evidence on the risk of postoperative bleeding in patients taking NOACs. If patients on NOACs present with abdominal symptoms following anterior approach to the lumbar spine, treating clinicians should have a high index of suspicion for retroperitoneal haematoma.

Percutaneous suction and irrigation for the treatment of recalcitrant pyogenic spondylodiscitis.

BACKGROUND: The primary management of pyogenic spondylodiscitis is conservative. Once the causative organism has been identified, by blood culture or biopsy, administration of appropriate intravenous antibiotics is started. Occasionally patients do not respond to antibiotics and surgical irrigation and debridement is needed. The treatment of these cases is challenging and controversial. Furthermore, many affected patients have significant comorbidities often precluding more extensive surgical intervention. The aim of this study is to describe early results of a novel, minimally invasive percutaneous technique for disc irrigation and debridement in pyogenic spondylodiscitis. MATERIALS AND METHODS: A series of 10 consecutive patients diagnosed with pyogenic spondylodiscitis received percutaneous disc irrigation and debridement. The procedure was performed by inserting two Jamshidi needles percutaneously into the disc space. Indications for surgery were poor response to antibiotic therapy (8 patients) and the need for more extensive biopsy (2 patients). Pre- and postoperative white blood cell count (WBC), C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), Oswestry disability index (ODI), and visual analogue score (VAS) for back pain were collected. Minimum follow-up was 18 months, with regular interval assessments. RESULTS: There were 7 males and 3 females with a mean age of 67 years. The mean WBC before surgery was 14.63 × 109/L (10.9-26.4) and dropped to 7.48 × 109/L (5.6-9.8) after surgery. The mean preoperative CRP was 188 mg/L (111-250) and decreased to 13.83 mg/L (5-21) after surgery. Similar improvements were seen with ESR. All patients reported significant improvements in ODI and VAS scores after surgery. The average hospital stay after surgery was 8.17 days. All patients had resolution of the infection, and there were no complications associated with the procedure. CONCLUSIONS: Our study confirms the feasibility and safety of our percutaneous technique for irrigation and debridement of pyogenic spondylodiscitis. Percutaneous irrigation and suction offers a truly minimally invasive option for managing recalcitrant spondylodiscitis or for diagnostic purposes. The approach used is very similar to discography and can be easily adapted to different hospital settings. LEVEL OF EVIDENCE: Level III.

Time Factor and Disc Herniation Size: Are They Really Predictive for Outcome of Urinary Dysfunction in Patients With Cauda Equina Syndrome?

BACKGROUND: Timing of surgery and the importance of the size of disc prolapse in cauda equina syndrome (CES) remain controversial. OBJECTIVE: To investigate whether there is a relationship between postoperative urinary function, preoperative duration of neurogenic lower urinary tract dysfunction (NLUTD), and the level of canal compromise. METHODS: Seventy-one patients operated for CES were prospectively identified between 2010 and 2013. Fifty-two cases with preoperative NLUTD were included. The "Prolapse: Canal ratio" (PCR) was calculated as a proportion of cross-sectional area of disc prolapse on total cross-sectional area of spinal canal. RESULTS: Median of preoperative duration of NLUTD was 72 h (48; 132) and period from first assessment to surgery 10.5 h (7; 18.5). Urinary incontinence was seen in 46.2% of patients, 38.4% had painless retention and 15.4% had painful retention. In 38.5% of cases, urinary symptoms persisted for more than 20 mo postoperatively. There was no correlation between duration of preoperative NLUTD and urinary dysfunction persistence (P = .921). The outcome was not significantly influenced by having surgery more than the 48 h after presentation (P = .135). Preoperative incontinence persisted in 58% and painless retention in 30% of cases. The mean PCR was 0.6 ± 0.18. There was no correlation between PCR and outcome (P = .537) even after adjusting for duration of preoperative NLUTD (P = .7264). CONCLUSION: No significant correlation was demonstrated between the preoperative duration of urinary dysfunction, the size of disc herniation relative to size of spinal canal, and postoperative urinary function in a large consecutive series of patients with CES.

Incomplete cauda equina syndrome secondary to haemorrhage within a Tarlov cyst.

Sacral perineural (Tarlov) cysts are benign, cerebrospinal fluid containing lesions of the spinal nerve root sheath. They are usually asymptomatic; however, a small proportion have the potential to cause compression of nerve roots and/or the cauda equina.We report a case of a 61-year-old man who presented with acute onset back pain associated with bilateral radiculopathy. Between referral and consultation, the patient developed urinary dysfunction which resolved spontaneously.MRI revealed haemorrhage within a Tarlov cyst, resulting in compression of the cauda equina. Due to the considerable clinical improvement at the time of consultation, surgical decompression of the cyst was not considered to be indicated.An interval MRI scan 8 weeks later demonstrated that the haemorrhage within the perineural cyst had spontaneously resolved and the patient remained asymptomatic at 5-year follow-up.

Anterior lumbar discectomy and fusion for acute cauda equina syndrome caused by recurrent disc prolapse: report of 3 cases.

There is a lack of information and consensus regarding the optimal treatment for recurrent disc herniation previously treated by posterior discectomy, and no reports have described an anterior approach for recurrent disc herniation causing cauda equina syndrome (CES). Revision posterior decompression, irrespective of the presence of CES, has been reported to be associated with significantly higher rates of dural tears, hematomas, and iatrogenic nerve root damage. The authors describe treatment and outcomes in 3 consecutive cases of patients who underwent anterior lumbar discectomy and fusion (ALDF) for CES caused by recurrent disc herniations that had been previously treated with posterior discectomy. All 3 patients were operated on within 12 hours of presentation and were treated with an anterior retroperitoneal lumbar approach. Follow-up ranged from 12 to 24 months. Complete retrieval of herniated disc material was achieved without encountering significant epidural scar tissue in all 3 cases. No perioperative infection or neurological injury occurred, and all 3 patients had neurological recovery with restoration of bladder and bowel function and improvement in back and leg pain. ALDF is one option to treat CES caused by recurrent lumbar disc prolapse previously treated with posterior discectomy. The main advantage is that it avoids dissection around epidural scar tissue, but the procedure is associated with other risks and further evaluation of its safety in larger series is required.

The current state of the evidence for the use of drains in spinal surgery: systematic review.

PURPOSE: Search for evidence pertaining to the effectiveness of drains used in spinal surgeries. METHOD: PubMed and EMBASE databases were searched for articles pertaining to the use of drains in all types of spinal surgery. The bibliographies of relevant studies were searched for additional papers that met the initial inclusion criteria. Level I and II studies were scored according to guidelines in the Cochrane Collaboration Back Review Group. We utilised the Population, Intervention, Comparison, Outcomes and Study design (PICOS) method to define our study eligibility criteria. RESULTS: Nineteen papers were identified: four level I studies, eight level III studies and seven level IV studies. The four level I, involving the randomization of patients into 'drain' and 'non-drain' groups, identified a total of 363 patients. Seven of the eight level III retrospective studies concluded that the use of drains did not reduce complications. Two of the seven level IV studies agreed with this conclusion. The remaining five level IV studies reported the benefits of lumbar drainage following dural tears. CONCLUSIONS: There is a paucity of published literature on the use of drains following spinal surgery. This is the first study to assess the evidence for the benefits of drains post-operatively in spinal surgery. The identified studies have shown that drains do not reduce the incidence of complications in anterior cervical discectomy and fusion, one and two level posterior cervical fusions, lumbar laminectomies, lumbar decompressions or discectomies and posterior spinal fusion for adolescent scoliosis. Further level I and II studies are needed.

Recommendations for Lengthening of Magnetically Controlled Growing Rods in Children With Pacemakers.

PURPOSE OF THE STUDY: Pacemakers are currently identified as a contraindication for the use of magnetic growth rods (MGRs). This arises from concern that magnetic fields generated by the MGR external remote controller (ERC) during lengthening procedures may induce pacemaker dysfunction. We investigated (1) whether MGR lengthening affects pacemaker function, and (2) if the magnetic field of a pacemaker affects MGR lengthening. METHODS: MGRs were tested in conjunction with an magnetic resonance imaging-compatible pacemaker, which was connected to a virtual patient under continuous cardiac monitoring. To determine whether pacemaker function was affected during MGR lengthening, the electrocardiogram trace was monitored for arrhythmias, whereas an ERC was applied to lengthen the MGRs at varying distances from the pacemaker. To investigate if MGR lengthening was affected by the presence of a pacemaker, at the start and end of the experiment, the ability of the rods to fully elongate and shorten was tested to check for conservation of function. RESULTS: When the pacemaker was in normal mode, <16 cm away from the activated ERC during MGR lengthening, pacemaker function was affected by the ERC's magnetic forces. At this distance, prophylactically switching the pacemaker to tonic mode before lengthening prevented occurrence of inappropriate pacing discharges. No deleterious effect of the pacemaker's magnetic field on the MGR lengthening mechanism was identified. CONCLUSIONS: Magnetic resonance imaging-compatible pacemakers appear safe for concomitant use with MGRs, provided a pacemaker technician prophylactically switches the pacemaker to tonic function before outpatient lengthening procedures. CLINICAL RELEVANCE: This experiment was designed to provide the first safety information on MGR lengthening in children with pacemakers. Although currently a rare clinical scenario, with increasing use of MGRs, this clinical scenario may arise more frequently in the future.

Do Growing Rods for Idiopathic Early Onset Scoliosis Improve Activity and Participation for Children?

OBJECTIVE: To investigate whether growing rod surgery for children with progressive idiopathic early onset scoliosis (EOS) effects activity and participation, and investigate factors that may affect this. STUDY DESIGN: Multicenter retrospective cohort study using prospectively collected data on 60 children with idiopathic EOS and significant scoliosis (defined as a Cobb angle >40°). Thirty underwent brace treatment, and 30, growth rod surgery. Questionnaire and radiographic data were recorded at 1 year. The validated Activities Scale for Kids performance version (ASKp) questionnaire was used to measure activity and participation. RESULTS: In the brace group, Cobb angle increased from 60° to 68°. There was no change in ASKp score. In the operative group, Cobb angle decreased from 67° to 45°. ASKp decreased from 91 to 88 (P < .01). Presence of spinal pain correlated with greater reduction in activity and participation scores in both groups, as did occurrence of complications in the operative group (P < .05). Both treatments permitted growth of the immature spine. CONCLUSIONS: In children with significant idiopathic EOS (Cobb angle>40°), growth rod surgery was associated with a reduction in activity and participation and Cobb angle, whereas brace treatment was associated with an increase in Cobb angle and no change in activity and participation. Pain was the most important factor affecting activity and participation in both groups.

Safety and compatibility of magnetic-controlled growing rods and magnetic resonance imaging.

PURPOSE: Magnetically controlled growth rods (MCGRs) are a new technology for the management of early-onset pediatric deformity enabling guided spinal growth by controlling the curvature. These rods contain a rare earth magnet and are contraindicated for MRI. We have investigated the behavior MCGRs to determine whether MRI adversely affects rod properties and to determine the extent of image distortion. METHODS: This is an in vitro experiment using two magnetic growth rods secured in a 1.5 T MRI. A gradient echo sequence MRI was performed to evaluate whether the rods elongated, contracted or rotated during scanning and a phantom model was used to evaluate the amount of artifact induced. RESULTS: The rod was not activated or subsequently impaired by the process of MRI. Image distortion of 28.9 cm along the long axis of the magnet and 20.1 cm perpendicular to this was seen with extension 10.6 cm cranial to the magnet housing. No negative effect was demonstrated on the magnetic rod elongation mechanism. CONCLUSIONS: This study has demonstrated that there are no detrimental effects of MRI on the MCGR and imaging of the head and neck phantom can still be interpreted. Further in vivo study is warranted.

Actuator pin fracture in magnetically controlled growing rods: two cases.

BACKGROUND CONTEXT: Magnetically controlled growing rods (MCGRs) are used in the management of early-onset scoliosis (EOS). Each MCGR contains a telescopic actuator that serves as the distraction element when stimulated by an external remote controller (ERC), permitting non-invasive lengthening in the outpatient clinic. PURPOSE: This report highlights a subtle cause of MCGR failure. We present the first two reported cases of lengthening pin fracture in patients with dual-MCGR constructs. STUDY DESIGN: We present two cases of patients with EOS treated with dual-construct MAGEC (MAGnetic Expansion Control, Ellipse Technologies Inc, Aliso Viejo, CA, USA) MCGRs. METHODS: A 12-year-old boy presented describing a "popping" sensation in his thoracic spine and resultant grating 36 months following MCGR insertion. RESULTS: A plain radiograph revealed a subtle fracture of the lengthening pin within the actuator of the right MCGR. Following identification of this case of implant failure, we reviewed the most recent radiographs of all nine of our patients treated with this MCGR in our institution, resulting in the discovery of bilateral MCGR lengthening pin fractures in an otherwise asymptomatic 11-year-old girl. CONCLUSIONS: Clinicians should have a high index of suspicion of structural implant failure when presented with histories similar to those reported in our first case, or following unsuccessful distraction of MCGRs. In such cases new radiographs should be taken, and all previous images should be reviewed for evidence of this phenomenon. Centers that document MCGR lengthening with ultrasound should obtain plain radiographs every 6 months to evaluate the structural integrity of the implant.

Presentation of cauda equina syndrome during labour.

Lumbar disc herniations are rare in pregnancy, with an incidence of 1:10,000. Less than 2% of these herniations result in cauda equina syndrome (CES). Diagnosing CES in pregnant patients can be difficult because changes in bladder and bowel habits are common in normal pregnancies. We present the case of a 29-year-old woman, with a history of lumbar radiculopathy, who presented at 39 weeks gestation with severe lower back and bilateral lower limb radiculopathy. Symptoms of CES began to develop only after the onset of labour. Diagnostic MRI was obtained following delivery and the patient was treated by microdiscectomy. Following surgery, bladder and bowel function began to normalise and at 3 months follow-up, she had made a full recovery. To the best of our knowledge, CES has never been reported to present during labour. This case highlights the diagnostic dilemma and need for a high index of suspicion.

Surgical correction of kyphotic deformity in a patient with Proteus syndrome.

BACKGROUND CONTEXT: Proteus syndrome (PS) is an extremely rare congenital disorder causing asymmetric overgrowth of different tissues. The etiology remains unclear. Limb deformities are common and often necessitate amputations. Only a few cases associated with spinal deformities have been described. PURPOSE: The aim was to report a rare case of PS associated with spinal deformity and its surgical management. STUDY DESIGN: A case of young boy with PS causing vertebral hypertrophy and kyphoscoliotic deformity, which was surgically corrected, is presented. METHODS: The patient was assessed clinically and with whole spine plain radiographs, computed tomography, and magnetic resonance imaging. Surgical correction was performed. RESULTS: Satisfactory correction of the deformity was achieved by posterior spinal fusion with instrumentation from T4-L5, five Ponte osteotomies T8-L1, and an L2 pedicle subtraction osteotomy. The kyphosis was corrected from 87° to 55°; there was improvement in all spinopelvic parameters. One year after surgery, there was maintenance of the deformity correction with no deterioration of the sagittal balance, and the patient was free of pain and had no loss of neurologic function. CONCLUSIONS: Proteus syndrome can be associated with spinal stenosis and deformity. Although the syndrome can be progressive in nature, the symptomatic spinal pathology should be treated appropriately.

Access-related complications in anterior lumbar surgery in patients over 60 years of age.

PURPOSE: The anterior approach is widely used for access to the lumbar spine in the setting of adult deformity either as a stand-alone procedure or in combined anterior-posterior procedures. Access-related complication rates have so far not been reported in an elderly patient population, in which it has been suggested that anterior lumbar surgery is indicated with caution. Here, the complication rates in patients over 60 years of age are reported. METHODS: A retrospective chart review in a consecutive series of 31 patients over 60 years of age and in which a retroperitoneal access to the lumbar spine was performed. All charts including anaesthetic charts were reviewed and the patients' demographics, exact surgical procedure, comorbidities, and potential risk factors, as well as intraoperative and vascular complications noted. Patients who had revision anterior surgery, anterior surgery for tumour resection, trauma or infection were excluded. RESULTS: The average age of patients was 64.9 years, ranging 60-81. Eighteen patients were female and 13 male. The average body mass index was 26.7 ranging 18.5-44.0. The indications for surgery were degenerative scoliosis (12 patients), degenerative spondylosis (7 patients), degenerative spondylolisthesis (5 patients), iatrogenic spondylolisthesis following prior posterior decompression (5 patients), and pseudarthrosis following posterolateral instrumented fusion (2 patients). In 10 patients, a single-level anterior lumbar interbody fusion (ALIF) was carried out (1 L3/4, 5 L4/5, 4 L5/S1) and in 11 patients ALIF was performed on two levels (1 L2-4, 1 L3-5, 9 L4-S1). In three patients, 3 levels from L3 to S1 were approached and in seven patients 4 levels from L2 to S1. Patients with three- and four-level anterior lumbar surgery had higher blood loss than two- and one-level surgery (616 ± 340 vs 439 ± 238, p = 0.036). The overall complication rate was 29% (9/31), which included four vascular injuries and one pulmonary embolism. The vascular complication rate was 13% (4/31) with two arterial and two venous injuries requiring repair. No major blood loss over 2,000 ml occurred. CONCLUSIONS: Anterior lumbar surgery in an elderly population does not necessarily have higher overall complication rates than in a younger population. The risk of vascular injury requiring repair was higher, but has not resulted in major blood loss and the procedure therefore can be carried out safely. The overall complication rate and blood loss compare favourably to complication rates in posterior adult deformity procedures.