Characteristics of deformity surgery in patients with severe and rigid cervical kyphosis (CK): results of the CSRS-Europe multi-centre study project.

INTRODUCTION AND PURPOSE: Little information exists on surgical characteristics, complications and outcomes with corrective surgery for rigid cervical kyphosis (CK). To collate the experience of international experts, the CSRS-Europe initiated an international multi-centre retrospective study. METHODS: Included were patients at all ages with rigid CK. Surgical and patient specific characteristics, complications and outcomes were studied. Radiographic assessment included global and regional sagittal parameters. Cervical sagittal balance was stratified according to the CSRS-Europe classification of sagittal cervical balance (types A-D). RESULTS: Eighty-eight patients with average age of 58 years were included. CK etiology was ankylosing spondlitis (n = 34), iatrogenic (n = 25), degenerative (n = 9), syndromatic (n = 6), neuromuscular (n = 4), traumatic (n = 5), and RA (n = 5). Blood loss averaged 957 ml and the osteotomy grade 4.CK-correction and blood loss increased with osteotomy grade (r = 0.4/0.6, p < .01). Patients with different preop sagittal balance types had different approaches, preop deformity parameters and postop alignment changes (e.g. C7-slope, C2-7 SVA, translation). Correction of the regional kyphosis angle (RKA) was average 34° (p < .01). CK-correction was increased in patients with osteoporosis and osteoporotic vertebrae (POV, p = .006). 22% of patients experienced a major long-term complication and 14% needed revision surgery. Patients with complications had larger preop RKA (p = .01), RKA-change (p = .005), and postop increase in distal junctional kyphosis angle (p = .02). The POV-Group more often experienced postop complications (p < .0001) and revision surgery (p = .02). Patients with revision surgery had a larger RKA-change (p = .003) and postop translation (p = .04). 21% of patients had a postop segmental motor deficit and the risk was elevated in the POV-Group (p = .001). CONCLUSIONS: Preop patient specific, radiographic and surgical variables had a significant bearing on alignment changes, outcomes and complication occurrence in the treatment of rigid CK.

Paraspinal muscle volume in patients with Scheuermann's Kyphosis.

To measure the cross-sectional area (CSA) of para-spinal muscles in Scheuermann's kyphosis patients. Preoperative MRI images of 16 Scheuermann's kyphosis patients were analysed and compared to 16 patients with normal MRI images (control group). The CSAs were measured at L3-4 and L4-5. Both groups showed similar demographics and patient characteristics. The multifidus muscles CSA were found to be significantly smaller at L3/4 level in Scheuermann's kyphosis patients (p = 0.022 on the left and p = 0.016 on the right side compared to control group). There was no significant change in multifidus CSA found at L4/5. The mean CSA of the extensor spinae muscles group were significantly smaller at all levels in Scheuermann's kyphosis patients : p = 0.001 bilaterally at L3/4 and p = 0.015 right side and p = 0.009 left side at L4/5 level. This study shows that patients with Scheuermann's kyphosis deformity have significantly smaller CSA of lumbar multifidus and extensor spinae muscles.

Magneto-optical properties of one-dimensional conjugated photonic crystal heterojunctions containing plasma layers.

In this paper, a 4×4 transfer matrix method has been used to investigate the optical and magneto-optical properties of 1D conjugated photonic crystal (CPC) heterojunctions containing plasma layers. A linearly polarized TM wave is obliquely incident onto stack. A large Faraday rotation as well as high transmission can be achieved simultaneously in our proposed structure. The influences of the external magnetic field, number of unit cells, incidence angle, and plasma frequency on the transmission and Faraday rotation angle have been analyzed. Results indicate that the proposed structure has strong enhancement of Faraday rotation angle with relatively high transmission. This prospective advantage of the structure is useful for tunable filters in the millimeter-wave region.

Access related complications in anterior lumbar surgery performed by spinal surgeons.

PURPOSE: Anterior lumbar surgery is a common procedure for anterior lumbar interbody fusion (ALIF) and artificial disc replacement (ADR). Our aim was to study the exposure related complications for anterior lumbar spinal surgery performed by spinal surgeons. METHODS: A retrospective review was performed for 304 consecutive patients who underwent anterior lumbar spinal surgery over 10 years (2001-2010) at our institution. Each patient's records were reviewed for patients' demographics, diagnosis, level(s) of surgery, procedure and complications related to access surgery. Patients undergoing anterior lumbar access for tumour resection, infection, trauma and revision surgeries were excluded. RESULTS: All patients underwent an anterior paramedian retroperitoneal approach from the left side. The mean age of patients was 43 years (10-73; 197 males, 107 females). Indications for surgery were degenerative disc disease (DDD 255), degenerative spondylolisthesis (23), scoliosis (18), iatrogenic spondylolisthesis (5) and pseudoarthrosis (3). The procedures performed were single level surgery--L5/S1 (n = 147), L4/5 (n = 62), L3/4 (n = 7); two levels--L4/5 and L5/S1 (n = 74), L3/4 and L4/5 (n = 4); three levels--L3/4, L4/5, L5/S1 (n = 5); four levels--L2/3, L3/4, L4/5, L5/S1 (n = 5). The operative procedures were single level ADR (n = 131), a single level ALIF (n = 87) with or without posterior fusion, two levels ALIF (n = 54), two levels ADR (n = 14), a combination of ADR/ALIF (n = 10), three levels ALIF (n = 1), three levels ADR/ALIF/ALIF (n = 1), ADR/ADR/ALIF (n = 2), four levels ALIF (n = 1) and finally 3 patients underwent a four level ADR/ADR/ALIF/ALIF. The overall complication rate was 61/304 (20 %). This included major complications (6.2 %)--venous injury requiring suture repair (n = 14, 4.6 %) and arterial injury (n = 5 [1.6 %], 3 repaired, 2 thrombolysed). Minor complications (13.8 %) included venous injury managed without repair (n = 5, 1.6 %), infection (n = 13, 4.3 %), incidental peritoneal opening (n = 12, 3.9 %), leg oedema (n = 2, 0.6 %) and others (n = 10, 3.3 %). We had no cases of retrograde ejaculation. CONCLUSION: We report a very thorough and critical review of our anterior lumbar access surgeries performed mostly for DDD and spondylolisthesis at L4/5 and L5/S1 levels. Vascular problems of any type (24/304, 7.8 %) were the most common complication during this approach. The incidence of major venous injury requiring repair was 14/304 (4.6 %) and arterial injury 5/304 (1.6 %). The requirement for a vascular surgeon with the vascular injury was 9/304 (3 %; 5 arterial injuries; 4 venous injuries). This also suggests that the majority of the major venous injuries were repaired by the spinal surgeon (10/14, 71 %). Our results are comparable to other studies and support the notion that anterior access surgery to the lumbar spine can be performed safely by spinal surgeons. With adequate training, spinal surgeons are capable of performing this approach without direct vascular support, but they should be available if required.

Comparison of three types of lumbar osteotomy for ankylosing spondylitis: a case series and evolution of a safe technique for instrumented reduction.

INTRODUCTION: The principles of correction of thoraco-lumbar kyphotic deformity (TKLD) in ankylosing spondylitis (AS) are essentially centred on lordosing osteotomies such as pedicle subtraction closing wedge osteotomy (CWO), polysegmental posterior lumbar wedge osteotomies (PWO) and Smith Peterson's open wedge osteotomy (OWO) of the lumbar spine. There have been no studies that compared the results of the three osteotomies performed by a single surgeon with a long-term follow-up. MATERIALS AND METHODS: A retrospective review of 31 patients with AS was performed: 12 patients underwent CWO, 10 had OWO, and 9 had PWO. Radiographic assessment was performed at 6, 12, 24, and 52 weeks and annually thereafter. Clinical assessment included blood loss, intensive care unit (ICU) stay, and surgical time recordings. All patients were assessed clinically at regular intervals and outcome measures recorded included Oswestry Disability Index (ODI), Visual Analogue Score (VAS) for pain, and SRS-22 (recorded in 23 patients). RESULTS: The mean age at surgery was 54.7 years (40-74 years) and mean duration of symptoms was 3 years (range, 5-8 years). Mean follow-up was 5 years (range, 2-10 years). There was no statistically significant difference between the three techniques with regard to mean duration of surgery and ICU stay. The mean duration of surgery was 7 h (range, 4-9 h) (OWO cases had shorter period than CWO and PWO cases, and the longest period was for CWO cases). The mean ICU stay was 3 days (range, 2-20 days) (the period of stay was shorter in general for OWO and slightly longer for CWO and PWO). Blood loss was expressed as percentage of estimated blood volume (EBV). The mean blood loss in PWO was 23 ± 15.4% (range, 9-36%), CWO was 28 ± 4.5% (range, 12-40%) and in OWO was 15 ± 11% (range, 13-99%). Mean correction of kyphosis was 38° (range, 25°-49°) with CWO, 28° with OWO (range, 24°-38°) and 30° with PWO (range, 28°-40°). In comparison to preoperative scores, statistically significant improvement was noted in all three groups in the postoperative period with regard to ODI, VAS and SRS-22 (p = 0.001, Wilcoxon signed-rank test). CONCLUSION: Better radiographic correction was noted in the CWO and PWO groups, although this was associated with increased blood loss, multiple levels of instrumentation, and increased surgical time compared to OWO. A new safe technique of instrumentation using temporary malleable rods to prevent sagittal translation during the reduction manoeuvre is also described.

The importance of an intact abdominal musculature mechanism in maintaining spinal sagittal balance. Case illustration in prune-belly syndrome.

STUDY DESIGN: A rare case of thoracic hypokyphotic deformity secondary to prune-belly syndrome is presented. OBJECTIVES: To discuss the role of an intact abdominal musculature mechanism in maintaining spinal sagittal balance, and to present a case illustration of prune-belly syndrome. SUMMARY OF BACKGROUND DATA: There has been an ongoing debate concerning the integrity of the abdominal musculature unit in maintaining spinal support and stability. It is now believed that intra-abdominal pressure hitherto generated plays an important role in the stabilization of the spine. Congenital aplasia of the abdominal musculature, termed prune-belly syndrome, might therefore result in the loss of spinal function and stability. The literature also is reviewed for the incidence of spinal deformities related to this condition. METHODS: A unique case of prune-belly syndrome in a 33-year-old man with congenital aplasia of the abdominal musculature is presented. RESULTS: The patient exhibited loss of the spinal sagittal balance, with resultant development of a thoracic hypokyphotic deformity and thoracolumbar scoliosis. CONCLUSIONS: Scoliosis appears to be the most commonly reported spinal deformity. Unequal compressive forces on the vertebral endplates may be the proposed mechanism for the spinal deformities. Compensatory lumbar paraspinal overactivity resulting from the inability to generate normal intra-abdominal pressures because of a deficient abdominal wall musculature mechanism seems to be the plausible explanation for the observed thoracic hypokyphatic deformity.

Low back pain with fracture of the pedicle and contralateral spondylolysis. A technique of surgical management.

We present a 26-year-old athlete with severe low back pain associated with a fracture of a lumbar pedicle and contralateral spondylolysis. The difficulties of diagnosis are discussed together with the subject of segmental pain referral. A technique of operative management is described involving instrumentation of the symptomatic level alone.

Dwyer-Hartshill transpedicular fixation for spinal fusion.

We report the technique and early results of the Dwyer-Hartshill method for segmental fixation of the spine. This uses pedicular screws wired to a rectangular frame and is indicated after laminectomy.

Atlanto-axial dislocation without fracture: case report of an ejection injury.

We describe an unusual injury to the upper cervical spine sustained during ejection from an aircraft. MRI provided an accurate and direct diagnosis of the severe ligamentous injuries.

Fractures of capitellum and trochlea.

The principles of management of capitellar and trochlear fractures are similar to any other intra-articular fracture. Accurate anatomic reduction, rigid internal fixation, and early mobilization of the elbow are prerequisites for a good functional result. Small fragments with minimal subchondral bone, not amenable to rigid internal fixation, are best treated by surgical resection. This article outlines the diagnosis, treatment, controversies, postoperative results, and complications of these rare elbow fractures.

Surgical anatomy of spinal accessory nerve: is trapezius functional deficit inevitable after division of the nerve?

The course of spinal accessory nerve in the posterior triangle, the innervation of the sternocleidomastoid and trapezius muscles and the contributions from the cervical plexus were studied in 20 cadaveric dissections. The nerve was most vulnerable to iatrogenic injuries after leaving the sternocleidomastoid. Direct innervation of trapezius by cervical plexus branches was noted in five dissections, whereas connections between the cervical plexus and the spinal accessory nerve were observed in 19 dissections. These were usually under the sternocleidomastoid (proximal to the level of division of the nerve in nerve transfer procedures). Although the contribution from the cervical plexus to trapezius innervation is considered minimal, trapezius function can be protected in neurotization procedures by transecting the spinal accessory nerve distal to its branches to the upper position of trapezius.

Stability of the lumbar spine and method of instrumentation.

We have carried out a biomechanical study to investigate the effect on flexion, extension, and rotation of seven systems of fixation on five cadaveric lumbar spines. Pedicle fixation proved the most effective method to restrict these movements. Facet screw fixation was also successful. Harrington distraction rods, the Hartshill rectangle and the Luque technique, although restricting slight flexion and extension, exerted little control over rotation. We conclude that pedicular fixation and facet joint fixation provide the greatest overall stability and might, therefore, be the best systems to consider for multilevel fusions in the lumbosacral region.

Combined anterior and posterior resection and spinal stabilization for aneurysmal bone cyst.

We report on a 19-year-old man with a 6-month history of pain and stiffness in the upper cervical region who proved to have a lytic lesion affecting the anterior and posterior elements of C2-4, causing a severe gibbous deformity at C3. The tumour was excised through a posterior approach, and spinal fusion with instrumentation was performed. Two weeks later, through a right-sided, anteromedial approach, the remaining tumour was excised, and the spine was reconstructed with tricortical iliac bone as a strut graft. The patient was placed in a Minerva jacket for 3 months, during which time a solid fusion was obtained. The histological diagnosis was aneurysmal bone cyst. The patient has remained pain free and suffered no recurrence 2 and a half years after surgery. Involvement of several adjacent cervical vertebrae by an aneurysmal bone cyst is rare, and conventional treatment with curettage and bone grafting is most likely to carry a high rate of recurrence and spinal instability. We recommend complete excision of the tumour in a combined staged procedure and instrumentation to prevent recurrence and avoid instability.

Segmental spinal instrumentation using short closed wire loops.

The Luque technique of segmental sublaminar instrumentation is now an established method of internal fixation in spinal surgery. The major difficulty encountered with the current technique is the danger of neurologic injury during the passage and handling of conventional wires, especially in extensive procedures. Great care is required to prevent inadvertent percussion of the wires already passed. The authors believe that by using short closed wire loops, these dangers have been minimized. Simple additional instrumentation has been devised to facilitate application of these loops. Apart from ease of application and handling, the short wire loops may offer a safer method of segmental sublaminar fixation.

Painful scoliosis secondary to an osteoid osteoma of the rib.

A 14-year-old girl with painful scoliosis was found to have an osteoid osteoma involving the body of the left seventh rib. Excision of the tumor was facilitated by intraoperative bone scanning that precisely located its position. Following surgery, preoperative pain was completely relieved and the spinal curvature had partially regressed. The importance of early diagnosis and excision of tumors is emphasized to prevent the establishment of a permanent structural scoliosis.

Osteoid osteoma of the lateral mass of C5. Should excision be combined with fusion?

A 10-year-old girl presented with a 1-year history of pain and stiffness in her neck associated with left shoulder and arm pain. This was found to be caused by an osteoid osteoma of the lateral mass of C5. Surgical excision of the tumour was performed through a posterior approach. Following surgery, the patient's pre-operative pain resolved. However, 3 months later she developed a recurrence of neck pain secondary to cervical instability. Further investigation revealed a grade II spondylolisthesis at the C5/6 level. A combined anterior and posterior fusion was performed and the patient's instability pain rapidly resolved. At her 18-months' follow-up a solid fusion was confirmed radiologically and the patient remained asymptomatic with no evidence of tumour recurrence. The purpose of this report is to highlight the difficulty in diagnosing this condition as well as to emphasise the surgical technique required. It would appear that excision of the lateral mass will result in instability. To prevent this, fusion of the spine should always be considered at the time of surgical excision of the tumour.

Thoracolumbar hernia: a rare cause of back pain.

We report a case of a hernia through the thoracolumbar fascia in a young adult male who presented with pain and swelling in the thoracolumbar region. Surgical repair of the defect was performed in the superficial layer of the thoracolumbar fascia and, 18 months following surgery, he remained asymptomatic. The purpose of this report is to make clinicians aware of a thoracolumbar hernia as a rare cause of back pain.

Surgical decompression: a life-saving procedure for an extensive spinal epidural abscess.

Extensive spinal epidural abscesses (SEAs) carry a high mortality rate. Traditionally they are treated non-operatively with long-term antibiotics and/or surgical decompression, but there is a continuing debate as to whether they should be managed by emergency surgical decompression. However, such decisions are made in the light of the clinical setting. We report the successful management of a female patient who presented with features of upper cervical cord compression and later developed septic shock and multisystem failure. Surgical decompression of the cervical spine and irrigation of the epidural space with a paediatric catheter was performed followed by tricortical strut grafting and plating. At review, 36 weeks after surgery, the patient remained asymptomatic, having made full neurological recovery. The purpose of this report is to highlight the importance of emergency surgical intervention for extensive SEA in the presence of progressive neurological loss associated with multisystem failure.