Synovial cysts associated with cauda equina syndrome in two dogs

OBJECTIVE

To report synovial cysts associated with cauda equina syndrome in 2 dogs.

STUDY DESIGN

Clinical cases.

ANIMALS

Two German Shepherd dogs.

METHODS

After magnetic resonance imaging detection, cysts were surgically removed via dorsal laminectomy.

RESULTS

Six and 8 months after surgery, both dogs were free of clinical signs and no pain was elicited on lumbosacral joint manipulation.

CONCLUSION

Although described in dogs, cysts at the lumbosacral joint might cause compression of the cauda equina nerve roots. Radical excision of the cyst capsule can result in resolution of clinical signs.

CLINICAL RELEVANCE

Synovial cysts should be considered in the differential diagnosis of dogs with cauda equina compression syndrome when lumbosacral degenerative joint disease is present.

Solitary thoracic osteochondroma: case report and review of the literature

OBJECTIVE AND IMPORTANCE

Osteochondromas are common benign bone tumors that rarely arise in the vertebral column. Intraspinal presentation of these tumors is usually circumscribed to the cervical regions with few tumors presenting in the thoracic vertebrae. We report a case of a thoracic solitary osteochondroma arising from within the vertebral body, review the cases reported in the literature, and propose recommendations for the surgical management of these challenging lesions.

CLINICAL PRESENTATION

A 26-year-old woman presented with clinical signs of spinal cord compression consisting of right lower extremity weakness and left lower extremity numbness. Magnetic resonance imaging showed a small enhancing epidural mass behind the vertebral body of T12.

INTERVENTION

A T12 corpectomy was performed with thoracolumbar fixation and fusion.

CONCLUSION

Our case is atypical in that the tumor arose from the posterior portion of the T12 body, causing spinal cord dysfunction that necessitated an anterior approach to T12 for corpectomy with thoracolumbar fixation and fusion. Surgical intervention was effective in completely resolving the patient's right lower extremity weakness.

Functional outcome after central corpectomy in poor-grade patients with cervical spondylotic myelopathy or ossified posterior longitudinal ligament

OBJECTIVE

We studied the long-term functional outcome in poor-grade patients (Nurick Grades 4 and 5) with cervical spondylotic myelopathy (CSM) or ossified posterior longitudinal ligament after central corpectomy (CC). We sought to determine whether there were any prognostic factors that could predict functional outcome in these patients.

METHODS

Functional outcome data were collected for 72 patients (68 men and 4 women; mean age, 49.7 yr; range, 30-67 yr) with CSM (60 patients) or OPLL (12 patients) of Nurick Grades 4 (55 patients) and 5 (17 patients). Uninstrumented CC was performed at 1 level in 12 patients, at 1 level combined with a discoidectomy at another level in 4 patients, at 2 levels in 50 patients, and at 2 levels plus a discoidectomy in 5 patients. The age at presentation (< or =50 yr or >50 yr), grade before surgery (4 or 5), the number of levels operated (1 or >1), diagnosis (CSM or ossified posterior longitudinal ligament), and duration of myelopathic symptoms (< or =12 mo or >12 mo) were studied for their effect on the functional outcome noted at the last follow-up. Functional outcome was graded as poor (no change in Nurick grade), fair (improvement of one Nurick grade), good (improvement of two Nurick grades), and cure (follow-up Nurick grade of 0 or 1).

RESULTS

The follow-up ranged from 9 to 104 months (mean, 36.3 mo). One patient died 3 weeks after CC after surgery for a perforated duodenal ulcer. There was transient operative morbidity in 12 patients (16.9%). The mean Nurick score improved from 4.24 to 2.47 (P < 0.001). Of the 54 patients (76%) who improved in their Nurick grade, the functional outcome was graded as fair in 13 patients (18.3%), good in 24 patients (33.8%), and cure in 17 patients (23.9%). The functional outcome was poor in 17 patients (23.9%). Functional improvement after CC was uniformly correlated with myelopathic symptoms of 12 months' duration or shorter. The other favorable prognostic indicators for improvement after CC were a diagnosis of CSM and preoperative Nurick Grade 5; however, patients with a preoperative Nurick grade of 4 were more likely to experience a cure.

CONCLUSION

More than three-fourths of patients with poor-grade CSM improve in their functional status after CC, with nearly 24% of patients obtaining a cure. Because patients with a duration of myelopathic symptoms of 12 months or less had the best functional outcome, early decompressive surgery should be offered to patients with poor-grade CSM.

The effects of free fat graft or cellulose membrane implants on laminectomy membrane formation in dogs

The purpose of this study was to determine the effect of cellulose membrane or free fat grafts (FFG) on laminectomy membrane (LM) formation. Eighteen dogs were randomly divided into three groups of six dogs. All dogs underwent a modified dorsal laminectomy on T(13)-L(1). The laminectomy defect was left uncovered in the control group but either a FFG or a cellulose membrane implant was provided in the other two groups. The dogs were evaluated through neurological examination, myelography, macroscopic roundness index of spinal cord and histological evaluations of epidural fibrosis and spinal cord. The results showed a significant difference between the control and the FFG group, with the FFG causing neurological deficits and spinal cord compression as assessed by the roundness index of the spinal cord. Both FFG and cellulose membrane were partially effective in preventing LM formation. The use of FFG was associated with a high rate of significant neurological complications and spinal cord lesions.

Spontaneous spinal epidural hematoma in a toddler--a case report

OBJECTS

Spontaneous spinal epidural hematoma (SSEDH) is rare in children below the age of 2 years. It can produce rapidly progressive neurological deficits.

METHODS

The authors report a case of SSEDH in a 15-month-old boy diagnosed by MRI. Suspension laminotomy and evacuation of the clot were done 48 h after the onset of symptoms. The patient made excellent neurological recovery. Computed tomography (CT) and MRI scanning carried out 6 months after surgery revealed good fusion of the laminotomy. A brief review of relevant literature is presented.

CONCLUSION

Although rare SSEDH requires immediate surgical decompression to avoid any permanent neurological deficit. Reconstructive surgical procedures like laminotomy are preferred in children where the incidence of spinal deformity is high following laminectomy.

Surgical treatment of 40 patients with thoracic ossification of the ligamentum flavum

OBJECT

The authors evaluated different surgical methods used to treat thoracic ossification of the ligamentum flavum (OLF).

METHODS

Data obtained in 40 patients who underwent posterior decompression for thoracic myelopathy caused by thoracic OLF were studied retrospectively. There were 32 men and eight women. All patients underwent posterior decompression in which laminoplasty was performed or laminectomy combined with lateral fusion. Every surgical specimen was stained with H & E, and scanning electron microscopy was performed in 20 cases. The mean follow-up period was 28 months. Postoperative outcomes were evaluated using a recovery scale based on the Japanese Orthopaedic Association classification. There were a total of 168 ossified segments in this series, 77.4% of which were located in the lower thoracic spine. Marginal osteophyte formation was found in 36 patients; in 32 of the 36 patients, these marginal osteophytes were located at the intervertebral space either higher or lower than the ossified segment. Scanning electron microscopy showed elastic fiber breakdown, proliferation of collagenous fibers, calcification, and OLF in the same microscopy region. Laminoplasty was performed in four patients. In three cases surgery resulted in unchanged or worse outcome (increased kyphotic deformity in two), and in one it resulted in good outcome. Laminectomy combined with lateral fusion was performed in 36 patients, in 30 cases of which it resulted in a good or fair outcome, and increased kyphotic deformity in only one. Of these 36 laminectomy-treated patients, an en bloc laminectomy-treated procedure was performed in 16 patients; in 11 of the 12 patients with lateral or diffuse-type lesions the surgery resulted in a good or fair outcome. En bloc laminectomy, however, seems ineffective in the treatment of patients with thickened, nodular-type thoracic OLF, as the procedure resulted in worse outcome in two of the four patients. The authors have thus developed a new modality of laminectomy that they have termed "separating laminectomy," which they performed in 16 patients with thickened, nodular-type OLF; in 13 cases it resulted in a good or fair outcome, and in only one case did it result in a worse outcome.

CONCLUSIONS

The pathogenesis of thoracic OLF is mainly due to the localized mechanical stress on the ligament. Laminectomy combined with lateral fusion is the treatment of choice for thoracic OLF; furthermore, in terms of the configuration of the ossified lesion, en bloc laminectomy is suitable for the treatment of lateral-type and diffuse-type OLF, and the separating laminectomy is suitable for the thickened, nodular-type OLF.

[Modified percutaneous balloon kyphoplasty at osteolysis of 11th thoracic vertebra and communication with the spinal canal. Case report and review of the literature]

This paper presents the case report of a 67-year-old man who came to our hospital suffering from severe osteolysis of the 11th thoracic vertebral body. The patient has been suffering from renal cell carcinoma for 2 years. During a routine control the above-mentioned lesion was found by chance. A few days later pain started in the thoracolumbar region. Treatment was intended to be palliative. Therefore, we looked for an option to stabilize the vertebral body as minimally invasive as possible. Because of a destroyed trailing edge of the vertebra, "normal" kyphoplasty was not possible. For this reason, we performed a modification, using one filled balloon as a kind of curtain between the vertebral body and spinal canal. With this technique we achieved an optimal filling of the destroyed vertebral body with cement, without any leakage. Two days postoperatively, the patient could leave our hospital without any pain symptoms.

A postnatal switch in GABAergic control of spinal cutaneous reflexes

GABAergic signalling exerts powerful inhibitory control over spinal tactile and nociceptive processing, but during development GABA can be depolarizing and the functional consequences of this upon neonatal pain processing is unknown. Here we show a postnatal switch in tonic GABA(A) receptor (GABA(A)R) modulation of cutaneous tactile and nociceptive reflexes from excitation to inhibition, but only in the intact spinal cord. Neonatal and 21-day-old (P21) rats were intrathecally treated with one of the GABA(A)R antagonists bicuculline and gabazine, with both compounds dose-dependently decreasing hindpaw mechanical and thermal withdrawal thresholds in P21 rats but increasing them in P3 neonates. Intrathecal gabazine also produced an increase in the cutaneous evoked electromyography (EMG) response of the biceps femoris in P21 rates but lowering the response in neonates. Injections of 3H-gabazine in the L4-L5 region at P3 confirmed that gabazine binding was restricted to the lumbar spinal cord. Spinalization of P3 neonates at the upper thoracic level prior to drug application reversed the behavioural and EMG responses to GABA antagonists so that they resembled those of P21 rats. The effects of spinalization were consistent with gabazine facilitation of ventral root potentials observed in isolated neonatal spinal cord. These data show a marked postnatal developmental switch in GABAergic control of neonatal nociception that is mediated by supraspinal structures and illustrate the importance of studying developmental circuits in the intact nervous system.

[A long-term follow-up of lumbar laminotomy and replantation]

OBJECTIVE

To evaluate lumbar laminotomy and replantation in prevention of spinal unstability and peridural adhesion after laminectomy.

METHODS

From February 1995 to March 2001, a total of 169 patients (96 males, 73 females, aged 22-63) with lesions in the lumbar vertebral canals underwent surgery, in which the lesions were removed after laminectomy and then the excised laminae were replanted.

RESULTS

The follow-up for 5-9 years showed that all the patients had no complications after the lesions were removed. According to the evaluation criteria formulated by WANG Yongti, 81 patients had an excellent result, 67 had a good result, 19 had a fair result, and 2 had a poor result. 87.6% of the patients obtained quite satisfactory results. The X-ray films demonstrated that the replanted laminae obtained bony healing and the spine was stable. The CT scanning demonstrated that the canals were enlarged with a smooth and glossy interior.

CONCLUSION

Lumbar laminotomy and replantation is reasonable in design and convenient in performance, which can be promoted as a basic operation in spinal surgery.

[Canal laminoplasty with titanium miniplate re-implantation of vertebral lamina]

OBJECTIVE

To evaluate the reliability and the advantage of canal laminoplasty with laminoplasty over laminectomy for treatment of lumbar spinal stenosis.

METHODS

From June 2000 to September 2004, the titanium miniplate fixation technique was applied to re-implantation of the vertebral lamina in the lumbar spine. The vertebral lamina was made with a specially-made osteotome and a special technique in 18 patients with lumbar spinal stenosis.

RESULTS

The patients were followed up for 1 yr and 8 mon on average (range, 3 mon-4 yr and 3 mon) and were observed to have a bony fusion of the re-implanted lamina 3-9 months postoperatively. There was no nonunion, displacement of the re-implanted lamina, overgrowth of the anterior bone edge of osteotomy, recompression of the nerves or instability of the lumbar spine.

CONCLUSION

The result demonstrates that canal laminoplasty with the titanium miniplate re-implantation of the vertebral lamina in lumbar spine can restore the normal anatomy, keep stability of the spine, and avoid adhesion and scar in the canal.

Femoral Nerve Palsy Following Mini-Open Extraperitoneal Lumbar Approach

Anterior extraperitoneal exposures to the lumbar spine are being increasingly used owing to the expanding use of novel technologies to treat degenerative disc disease. Lumbar plexus injuries are potential, albeit uncommon, complications of such exposures and can lead to significant perioperative morbidity. In this report, we present three patients with thoracolumbar fractures who sustained isolated femoral nerve palsies after a mini-open extraperitoneal approach to the midlumbar spine was undertaken to perform a partial corpectomy. To further understand the pathophysiology of this nerve injury, we conducted a cadaveric experiment to evaluate the effect of performing this approach and the effect of hip positioning on linear displacement of the femoral nerve. The displacement of the femoral nerve during the anterolateral extraperitoneal exposure through a 4- to 6-cm incision was equal to 6.6% of the full femoral nerve length. Relaxation of the femoral nerve was equal to 25% of the full nerve length when the hip was flexed to 90 degrees in neutral abduction-adduction. We conclude that the anterolateral extraperitoneal exposure of the midlumbar spine can potentially stretch the femoral nerve beyond its physiologic limits, particularly in trauma cases where exposure of the lateral vertebral body necessitates substantial retraction of the psoas muscle. The avoidance of self-retaining retractors for prolonged periods of time and the positioning of the hip in flexion may help to avoid such nerve injuries.

Cervical extradural meningioma with rapidly progressive myelopathy

A 50-year-old man noticed numbness of both hands. Muscle strength in the upper and lower extremities progressively deteriorated, and he became unable to stand or hold a cup over a five-day period. MRI showed an extradural tumour encasing the anterior, posterior and right lateral aspects of the cervical spinal cord, maximal at C3-4 but extending to C1, and emerging from the right C3-4 intervertebral foramen. At surgery, the tumour was entirely extradural. Histological examination revealed a meningioma. The patient recovered without neurological deficit with no recurrence 3 years after surgery.

Spinal compression due to ossified yellow ligament: a short series of 5 patients and literature review

BACKGROUND

Ossification of ligamentum flavum in the thoracic region causing compressive myelopathy among middle-aged patients is a poorly described entity.

CASE DESCRIPTION

Five patients of Indian origin with OYL are described. Their clinical presentations, surgical options, and long-term outcome are presented. Radiologic and clinical follow-up of one of the patient is described over a span of 10 years.

CONCLUSIONS

Decompressive laminectomy and excision of the OYL is the commonly performed surgical procedure. A rapid neurologic improvement follows decompression. The persistent spasticity in certain patients is attributed to irreversible changes within the cord. The disease is thought to be progressive in nature. The prolonged follow-up of these patients suggests that the long-term prognosis is poor. Selective racial involvement and variable clinical presentations, with treatment options, are discussed.

Comparison of Minimally Invasive and Conventional Open Posterolateral Lumbar Fusion Using Magnetic Resonance Imaging and Retraction Pressure Studies

OBJECTIVE

To determine whether minimally invasive lumbar spinal fusion results in less paraspinal muscle damage than conventional open posterior fusion.

METHODS

The maximum intramuscular pressure (IMP) generated by a minimally invasive and standard open retractor was compared in cadavers using an ultra-miniature pressure transducer. In a second clinical study, eight patients with either minimally invasive or open posterolateral lumbar spinal fusion underwent magnetic resonance imaging (MRI) scanning approximately 6 months post surgery. MRI was used to estimate edema and atrophy within multifidus, with T2 mapping and diffusion-weighted imaging allowing quantification of differences between the two surgical techniques.

RESULTS

IMP measured with the minimally invasive retractor was 1.4 versus 4.7 kPa with the open retractor (P < 0.001). The minimally invasive retractor produced a transient maximal IMP only on initial expansion. Maximum IMP was constant throughout open retractor deployment. Striking visual differences in muscle edema were seen between open and minimally invasive groups on MRI. The mean T2 relaxation time at the level of fusion was 47 milliseconds in the minimally invasive and 90 milliseconds in the open group (P = 0.013). The mean apparent diffusion coefficient was 1357 x 10(-6) mm/s and 1626 x 10(-6) mm(2)/s (P = 0.0184), respectively.

CONCLUSIONS

The peak IMP generated by the minimally invasive retractor was significantly less than with the open retractor. Postoperatively, less muscle edema was demonstrated after the minimally invasive lumbar spinal fusion, with lower mean T2 and apparent diffusion coefficient measurements supporting the hypothesis that less damage occurs using a minimally invasive approach.

two-stage operation for resection of spinal cord astrocytomas: technical case report of three cases

OBJECTIVE AND IMPORTANCE

Surgery for excision of intramedullary spinal cord tumors without increasing neurological deficit is one of the more difficult operations in spinal surgery. In particular, infiltrating astrocytomas without a clear cleavage between the tumor and normal spinal cord parenchyma are difficult to remove totally without producing additional neurological impairment. In this study, we describe a two-stage resection facilitating total resection of intramedullary tumors.

CLINICAL PRESENTATION

Three cases of spinal cord astrocytomas were treated using a two-staged method.

TECHNIQUE

The first surgery included myelotomy, biopsy and duroplasty. A thin expanded polytetrafluoroethylene sheet was placed between the dorsal surface of the spinal cord and dura mater to prevent adhesions. Two or 3 weeks after surgery, a second surgery was performed to remove the now exophytic tumor.

RESULTS

Magnetic resonance imaging scans showed exophytic extrusion of the tumor in all three cases before the second operation. In each patient, we were able to carry out gross total removal of the tumors without additional neurological deficit except for transient joint position sense loss in one case. All three patients remain neurologically stable without evidence of tumor recurrence more than 3 years after surgery.

CONCLUSION

A two-stage operation may enhance the surgeon's ability to completely resect extensive low-grade spinal cord astrocytomas and, at the same time preserve neurological function.

C3-6 laminoplasty takes over C3-7 laminoplasty with significantly lower incidence of axial neck pain

Five-lamina (C3-7) procedure is the most popular cervical laminoplasty and there have been no studies on the most appropriate number of laminae to be opened. We prospectively reduced the range of laminoplasty from C3-7 to C3-6 in 2002 and compared the outcome of C3-6 laminoplasty (n=37) to that of C3-7 laminoplasty (n=28). In both groups, neurological gain was satisfactory, radiographic changes were minimal, and postoperative MRI indicated sufficient expansion of the dura and the spinal cord. Average operating period was significantly shorter, and length of the operative wound was significantly less in the C3-6 group than in the C3-7 group. Postoperative axial neck pain was significantly rarer after C3-6 laminoplasty than after C3-7 laminoplasty (5.4% vs. 29%, P=0.015). Due to its simplicity and various benefits, C3-6 laminoplasty is a promising alternative to conventional C3-7 laminoplasty for treatment of multisegmental compression myelopathy.

Diagnosis and management of juxtafacet cysts

Juxtafacet cysts are lesions that are associated with spinal facet joints. Although these lesions are frequently noted as incidental findings on imaging studies of the spine, they may produce symptoms in some patients. Juxtafacet cysts can mimic herniated discs, resulting in symptoms from focal nerve root and/or spinal cord compression. Some of these lesions are associated with spinal instability, and patients may require spinal fusion to address this underlying disorder. Conservative therapy for symptomatic lesions is often unsuccessful, although there are reports of spontaneous resolution of these cysts as well as the symptoms associated with them. Surgical therapy should be focused on decompression of the lesions causing nerve root compression and the accompanying symptoms, while recognizing that instability requiring fusion may be present in some but not all cases.

[Balloon-assisted percutaneous vertebroplasty in patients with osteoporotic vertebral body compression fractures--first results]

PURPOSE

To determine the feasibility, efficacy and safety of balloon-assisted percutaneous vertebroplasty (BA-VP) in patients with osteoporotic vertebral compression fractures (VCFs).

MATERIALS AND METHODS

In 47 patients (29 women, 18 men; mean age: 70 years and 4 months) with severe VCFs, 66 BA-VPs were performed via a unipedicular access. After initial puncture (under combined fluoroscopy and CT guidance) of the vertebral body (VB), the needle was retraced by 1.5 cm, and a 12-mm Fogarty balloon catheter was introduced and inflated using 2-4 ml diluted contrast media (CM). After the subsequent removal of the catheter and repositioning of the needle, vertebroplasty was performed.

RESULTS

The mean volume of PMMA injected was 4.4 ml (2.5-7.2 ml). Pain reduction (measured by the Visual Analogue Scale) was achieved in 95 % of the patients, dropping from on average 8.0 pre-intervention to 2.2 after a mean follow-up of 8 months. A reduction of the pain relieving medication was achieved in 68 % of the cases and patient activity improved markedly. No severe or clinically relevant complications were observed. Cement leakage occurred by filling of epidural and paravertebral veins in 9.1 and 6.1 % of the cases, respectively. Leakage into the paravertebral soft tissues was seen in 3.0 % of the patients and to the adjacent disc space in 10.6 % of the cases.

CONCLUSION

Vertebroplasty and kyphoplasty are currently used to treat osteoporotic VCFs but show either a comparatively high leakage rate or are rather complex and expensive. Balloon-assisted vertebroplasty seems to combine advantages from both methods and is effective, safe and comparatively inexpensive.

Spinal Burkitt's lymphoma in adults

Adult Burkitt's lymphoma is an uncommon disease. Few cases of spinal involvement in adults with sporadic Burkitt's lymphoma are reported in the literature. We present a case of a middle-aged man who was found to have an epidural mass in the thoracic spine when investigated for back pain and lower extremity weakness. He underwent a laminectomy with resection of the epidural mass. Histologic examination revealed a primary Burkitt's lymphoma of the spinal cord. He was treated with aggressive chemotherapy and is now experiencing remission of his disease. We also present a review of the literature for the etiology and clinical features of other spinal lymphomas and Burkitt's lymphoma involving the spine in adults.

Clinical and radiographically/neuroimaging documented outcome in transforaminal lumbar interbody fusion

Object

Although transforaminal lumbar interbody fusion (TLIF) is an increasingly popular surgical technique, there are a limited number of studies in which investigators have stratified outcome data with respect to surgical indications or documented radiographically proven and clinical results with respect to disc space height (DSH). The authors conducted a study to evaluate the long-term outcomes after TLIF with respect to surgical indication and radiographic/neuroimaging results.

Methods

Thirty-three consecutive TLIF-treated patients underwent follow-up investigation for a mean of 37 months. Isthmic spondylolysis was present in eight patients, recurrent disc herniation in 14, and degenerative disc disease (DDD) in 11. The operative technique involved the placement of interbody structural allograft, pedicle screw instrumentation, and morcellized autograft in the anterior interbody space and the contralateral intertransverse gutter. Surgery was performed at L4–5 in 16 patients, L5–S1 in 14, L3–4 in two, and both L4–5 and L5–S1 in one patient.

Preoperative symptoms were back pain (in 91% of cases), leg pain (in 94%), sensory loss (in 67%), and motor deficits (in 30%). Postoperatively, back pain was improved in 67% of the patients, unchanged in 27%, and worsened in 7%. Leg pain improved in 80% of patients, was unchanged in 10%, and worsened in 10%. Outcome, as measured using the Prolo Functional and Economic Scales, improved from a score of 4.9 to 7. In patients with spondylolysis and recurrent disc herniation outcomes were better than in those with DDD only. There was no correlation of outcome with symptom duration, patient age, or level of surgery. In an independent review of pre- and late postoperative radiographs no significant differences in lordosis angles, Cobb angles, or DSHs were found. Fusion occurred in all cases.

Conclusions

The TLIF procedure was associated with good clinical outcomes and a high fusion rate but no change in the DSH. Patients who present with spondylolysis and recurrent herniations experience better outcome than those with degenerative disease alone.

Thoracic ossified meningioma and osteoporotic burst fracture: treatment with combined vertebroplasty and laminectomy without instrumentation

✓ Although spinal meningioma is a common benign neoplasm, the ossified variant is rare. No more than 20 sporadic cases were reported in the literature between 1977 and January 2005. Recently, the authors treated a patient with a symptomatic ossified meningioma located in the posterior aspect of T-11 and an associated osteoporotic T-11 burst fracture. The tumor was completely removed by T10–11 laminectomy and transpedicular vertebroplasty was performed. The kyphotic deformity of the T-11 burst fracture was partially reduced and maintained for at least 2 months after vertebroplasty and laminectomy. The clinical presentation and management of this case are reported.

Transforaminal lumbar interbody fusion: an independent assessment of outcomes in a difficult patient population

BACKGROUND

Transforaminal lumbar interbody fusion is becoming increasingly popular for the surgical treatment of lumbar degenerative conditions. However, the outcomes following the procedure have only begun to be evaluated.

MATERIAL/METHODS

The authors reviewed all patients previously treated by TLIF at our tertiary center with minimum two year follow-up. Between 1997 and 2001, twenty-seven patients underwent the procedure. They were evaluated clinically and radiographically at regular intervals for a minimum two years following surgery and longer term follow-up was carried out by telephone interview. Long-term follow-up was undertaken by an independent assessor (a spine surgeon not directly involved in the patient's care) and outcomes were assessed using the measure designed by Macnab/McCulloch/An. Follow-up averaged 30 months and ranged from 24 to 42 months.

RESULTS

All but two patients obtained a solid radiographic arthrodesis and complications were few. However, only eleven patients obtained excellent or good clinical results, while 16 had fair or poor outcomes.

CONCLUSIONS

TLIF is a technically demanding procedure which can be done with relatively few complications and offers excellent rates of arthrodesis. However, the outcomes of the procedure and indications for the procedure in difficult patient populations clearly require further study.

Surgical outcome of ossification of the posterior longitudinal ligament (OPLL) of the thoracic spine: implication of the type of ossification and surgical options

OBJECTIVE

Ossification of the posterior longitudinal ligament (OPLL) in the thoracic spine produces myelopathy through anterior spinal cord compression that is usually progressive and unaffected by conservative treatment. Therefore, early decompressive surgery is imperative. However, decompression surgery of thoracic myelopathy is difficult, and the outcome is often poor. A retrospective study was conducted to investigate the surgical outcome of 21 patients with thoracic OPLL to evaluate which type of surgical approach is better and which type of thoracic OPLL results in a better surgical outcome.

METHODS

A total of 21 patients with thoracic OPLL (10 men and 11 women; mean age 54 years), who underwent surgical treatment at our department from March 1985 to October 2000, were included in the study. Seven patients exhibited the flat-type OPLL and underwent either anterior decompression and fusion (one patient), anterior decompression via a posterior approach (three patients), or expansive laminoplasty (three patients). Fourteen patients exhibited the beak-type OPLL and also underwent either anterior decompression and fusion (two patients), anterior decompression via a posterior approach (six patients), or expansive laminoplasty (six patients).

RESULTS

Regarding of operative time and blood loss, there were no marked differences between the two types of OPLL, regardless of the type of surgical procedure; anterior decompression and fusion and anterior decompression via a posterior approach yielded longer operative times and larger blood loss volumes than expansive laminoplasty. Concerning clinical outcome, there were five cases of neurologic deterioration. All of the five deteriorated cases were of the beak-type OPLL treated by a posterior approach. Two of these patients were treated with expansive laminoplasty.

CONCLUSIONS

There were five instances of neurologic deterioration in our thoracic OPLL series, and all of them exhibited beak-type OPLL. In the beak-type OPLL, a subtle alteration in the spinal alignment during posterior decompression procedures may increase spinal cord compression, leading to the deterioration of symptoms. A potential increase in kyphosis following laminectomy should be avoided by fixation with a temporary rod. If intraoperative monitoring suggests spinal cord dysfunction, an anterior decompression procedure should be attempted as soon as possible.

Chordoma of the mobile spine: fifty years of experience

STUDY DESIGN

A consecutive series of 52 chordomas of the mobile spine observed over a 50-year period includes a retrospective review of 15 cases treated prior to 1991 and a prospective group of 37 cases treated from 1991 to 2002.

OBJECTIVES

This series reviews epidemiologic issues as well as clinical patterns of spinal chordomas. We attempt to correlate tumor extent, treatment, and outcomes over time.

SUMMARY OF BACKGROUND DATA

Chordoma is the most frequent primary tumor of the mobile spine. Due to slow growth, both initial symptoms and recurrences after treatment arise later, making it difficult to evaluate the effectiveness of treatment protocols.

METHODS

A prospective series of 37 cases is compared with a retrospective group of 15 patients observed between 1954 and 1991. In the prospective study, all patients had imaging studies, and oncologic and surgical staging. When en bloc resection was not feasible, intralesional extracapsular excision was combined with radiation therapy. The prospective patients were clinically evaluated and imaged. Patients in the retrospective group were evaluated by chart and available images; of these, only one en bloc resection (intralesional margin) was performed. Survivors were all evaluated clinically and had radiographic studies.

RESULTS

Forty-eight patients were available for long-term follow-up. Four died due to post-operative complications, and six due to disease less than 2 years after treatment. Forty-two patients were followed over 2 years; 26 patients had over 5 years follow-up. All patients having radiation alone, intralesional excision, or a combination had recurrences in less than 2 years, and died in some cases after a long survival with symptomatic disease. Intralesional extracapsular excision with radiation had a high rate of recurrence (12 of 16 at average 30 months), but 3 patients are continuously disease-free (CDF) at mean 52 months and 5 are alive with disease at average 69 months (ranging 24 to 146). Twelve of 18 patients having en bloc resection are CDF at average 8 years (48 to 155 months). The remaining 6 recurred and of these 1 died. All of these (6) had been previously treated and/or had en bloc resections with contaminated margins.

CONCLUSIONS

The only treatment protocol associated with CDF at follow-up longer than 5 years is margin-free en bloc resection.