Thoracoscopic surgical approaches for treating various thoracic spinal region diseases

AIM

Minimally invasive surgery is currently a goal for surgical intervention in the spine. The effectiveness of endoscopic thoracic spine surgery and technological improvements are two factors that are always under consideration in the practice of spinal surgery.

MATERIAL AND METHODS

We present twenty-five patients whose thoracoscopic spinal surgeries were performed between 2002 and 2008 for the treatment of various spinal diseases. Eleven patients with thoracic disc herniation, five patients with traumatic thoracic spinal compressive fracture, six patients with metastatic thoracic spinal tumors and three patients with tubercular spondylitis underwent thoracoscopic spine surgery. Clinical evaluations were performed at 3, 6,12 and 24 months post-surgery. The Oswestry disability questionnaire and linear visual analog scale (VAS) were used for the evaluation of pain.

RESULTS

Postoperatively, two patients had lung contusions, one patient had pneumonia and one patient had instability. There were significant initial improvements in both the Oswestry score and the VAS pain score up to 6 months (p<0.05). The average relative difference in pain scores in all groups was not significant at 12 and 24 months (p>0.05).

CONCLUSION

The favorable results of thoracoscopic spinal surgery encourage its application to situations in which a conventional thoracic approach is indicated. Thoracoscopic spine surgery is applicable to all patients with various spinal diseases.

Osteoid osteoma and osteoblastoma of the cervical spine: the cause of unusual persistent neck pain

BACKGROUND

The most important symptom in patients with osteoid osteoma and osteoblastoma is a resistant localized neck pain and stiffness in the spine.

OBJECTIVE

To evaluate and analyze 6 cases of osteoid osteoma and osteoblastoma of the cervical spine that were surgically treated over a 7-year period and to emphasize the unusual persistent neck pain associated with osteoid osteoma and osteoblastoma of the cervical spine.

STUDY DESIGN

Retrospective study.

METHODS

Six patients, 3 male and 3 female, with a mean age of 21 years (range 16-31) diagnosed with osteoid osteoma or osteoblastoma during 2003 to 2009 were analyzed retrospectively. The preoperative neurological and clinical symptoms, neck pain duration, preoperative deformity, location of lesion, radiological findings, surgical technique and clinical follow-up outcomes of each patient were evaluated.

RESULTS

The average follow-up duration was 40.5 months (range, 19 to 83 months). Three patients had osteoid osteoma (2 female and one male), and 3 patients had osteoblastoma (one female and 2 male). Two male patients had recurrent osteoblastoma. The locations of the lesions were as follows: C7 (2 patients), C3 (one patient), C2 (one patient), C3-C4 (one patient) and C5-C6 (one patient). The most common symptom was local neck pain in the region of the tumor. Among all patients, only one patient, who had osteoblastoma, had neurological deficits (right C5-C6 root symptoms). The other patients had no neurological deficits. All patients were treated with surgical resection using microsurgery. Two patients underwent only tumor resection, one patient underwent tumor resection and fusion, and the other 3 patients underwent tumor resection, fusion and spinal instrumentation. No perioperative complications developed in any of our patients. There was no tumor recurrence during the follow-up period.

LIMITATIONS

A retrospective study with 6 analyses of cases.

CONCLUSION

Surgical treatment of osteoid osteoma and osteoblastoma of the spine has been standardized. The most common symptom of osteoid osteoma and osteoblastoma of the cervical spine is local persistent neck pain in the region of the tumor. This symptom can be significant in the diagnosis of these tumors.

Dynamic stabilization of the spine: a new classification system

Fusion surgeries are still the gold standard in the treatment of the degenerative spine. Spinal fusion has some problems, however. Adjacent segment disease, donor place ailment, and the morbidity of the surgery has emerged as important problems over the years. As a consequence of such complications after fusion, the search for an alternative treatment for the degenerative spine widened. While trying to maintain the motion in the joint, dynamic stabilization aims to remove the pain by distributing the weight between anterior and posterior elements of the spine. Various new devices have now been developed for the dynamic stabilization of the spine. In this report, the dynamic stabilization devices of the spine are classified anew and, the authors explain briefly the historical evolution process, specialties, indications and contraindications of these dynamic stabilization devices.

Posterior dynamic stabilization in the treatment of lumbar degenerative disc disease: 2-year follow-up

BACKGROUND

A prospective pilot study was designed to evaluate the role of a posterior dynamic stabilization technique in the surgical treatment of degenerative disc disease. Posterior dynamic stabilization with a hinged screw is a new concept in the surgical treatment of degenerative disc disease of the lumbar spine. The traditional surgical treatment is to apply a fusion procedure. However, numerous reports showed unsatisfactory clinical outcomes even when patients have satisfactory radiological outcomes following fusion procedures.

MATERIAL AND METHODS

The study included patients who were surgically treated with a dynamic stabilization technique due to painful degenerative disc disease. Clinical and radiological findings for the 20 participating patients were analyzed in a 2-year follow-up study. Preoperative and postoperative data at the 3 (rd), 12 (th) and 24 (th) month were collected for both clinical and radiological outcomes. Statistical analyses between preoperative and postoperative data were performed using the Wilcoxon test.

RESULTS

The clinical outcome measurements (VAS, ODI) showed significant improvement in all postoperative measurements compared to preoperative values. The mean preoperative visual analogue score (VAS, 7.9) and Oswestry Disability Index (ODI 59.2) significantly decreased to 0.8 for VAS and 9.2 for ODI, at 2 years post-operation (p<0.05). The radiological studies showed no significant changes between pre- and postoperative values, in all parameters. There was no mortality or morbidity.

CONCLUSIONS

The results of this pilot study are encouraging. Dynamic stabilization may be an effective technique in the surgical treatment of painful degenerative disc disease. A larger series study, with longer follow-up periods and with control groups is needed to determine the success and safety of posterior dynamic stabilization in the surgical treatment of degenerative disc disease.

Comparison of posterior dynamic and posterior rigid transpedicular stabilization with fusion to treat degenerative spondylolisthesis

This article describes the clinical and radiological outcomes of a comparison of posterior dynamic transpedicular stabilization and posterior rigid transpedicular stabilization with fusion after decompression in the treatment of degenerative spondylolisthesis. This prospective clinical and radiologic study was conducted between 2004 and 2007 and included 46 patients, of whom 33 were women (71.7%) and 13 were men (28.3%). Mean patient age was 61.67+/-10.80 years (range, 45-89 years). Twenty-six patients who underwent lumbar decompression and posterior dynamic transpedicular stabilization were followed for a mean of 38 months (range, 24-55 months). In the fusion group, 20 patients who underwent lumbar decompression and rigid stabilization with fusion were followed for a mean of 44 months (range, 26-64 months). The intervertebral space measurements of the dynamic group at the preoperative examination and at 12 and 24 months postoperatively were statistically significantly higher than the intervertebral space measurements of the fusion group (P<.05). In the dynamic group, complications occurred in 2 patients; the first was a screw malposition, which was improved with revision surgery within 1 month of the initial surgery, and the second was a fusion performed in the second year in 1 patient because the patient reported continued pain. In the fusion group, adjacent segment disease was observed in 1 patient, with subsequent reoperation. Lumbar decompression and posterior dynamic transpedicular stabilization yield satisfactory results in the treatment of degenerative lumbar spondylolisthesis and can be considered a valid alternative to fusion.

Dynamic lumbar pedicle screw-rod stabilization: two-year follow-up and comparison with fusion

Background:

A lumbar pedicular dynamic stabilization system (LPDSS) is an alternative to fusion for treatment of degenerative disc disease (DDD). In this study, clinical and radiological results of one LPDSS (Saphinaz, Medikon AS, Turkey) were compared with results of rigid fixation after two-year follow-up.

Methods:

All patients had anteroposterior and lateral standing x-rays of the lumbar spine preoperatively and at 3 months, 12 months and 24 months after surgery. Lordosis of the lumbar spine, segmental lordosis and ratio of the height of the intervertebral disc spaces (IVS) measured preoperatively and at 3 months, 12 months and 24 months after surgery.

All patients underwent MRI and/or CT preoperatively, 3months, 12 months and 24 months postoperatively. The ratio of intervertebral disc space to vertebral body height (IVS) and segmental and lumbar lordosis were evaluated preoperatively and postoperatively. Pain scores were evaluated via Visual Analog Scale (VAS) and Oswestry Disability Index (ODI) preoperatively and postoperatively.

Results:

In both groups, the VAS and ODI scores decreased significantly from preoperatively to postoperatively. There was no difference in the scores between groups except that a lower VAS and ODI scores were observed after 3 months in the LPDSS group. In both groups, the IVS ratio remained unchanged between preoperative and postoperative conditions. The lumbar and segmental lordotic angles decreased insignificantly to preoperative levels in the months following surgery.

Conclusions:

Patients with LPDSS had equivalent relief of pain and maintenance of sagittal balance to patients with standard rigid screw-rod fixation. LPDSS appears to be a good alternative to rigid fixation.

Clinical analysis of 21 cases of spinal cord ependymoma : positive clinical results of gross total resection

OBJECTIVE

To evaluate the clinical results of gross total resection in the surgical approach to spinal ependymoma.

METHODS

Between June 1995 and May 2009, 13 males and 8 females (mean age 34) diagnosed with intramedullary or extramedullary spinal ependymoma were surgically treated at our centre. The neurological and functional state of each patient were evaluated according to the modified McCormick scale.

RESULTS

The average follow-up duration was 54 months (ranging from 12 to 168 months). The locations of the lesions were: thoracic region (4, 19%), lumbar region (7, 34%), cervical region (4, 19%), cervicothoracic region (3, 14%) and conus medullaris (3, 14%). Four patients (19%) had deterioration of neurological function in the early postoperative period. The neurological function of three patients was completely recovered at the 6th postoperative month, while that of another patient was recovered at the 14th month. In the last assessment of neurological function, 20 patients (95%) were assessed as McCormick grade 1. No perioperative complications developed in any of our patients. In one patient's 24-month assessment, tumour recurrence was observed. Re-operation was not performed and the patient was taken under observation.

CONCLUSION

Two determinants of good clinical results after spinal ependymoma surgery are a gross total resection of the tumour and a good neurological condition before the operation. Although neurological deficits in the early postoperative period can develop as a result of gross total tumour resection, significant improvement is observed six months after the operation.

Minimum two-year follow-up of cases with recurrent disc herniation treated with microdiscectomy and posterior dynamic transpedicular stabilisation

The objective of this article is to evaluate two-year clinical and radiological follow-up results for patients who were treated with microdiscectomy and posterior dynamic transpedicular stabilisation (PDTS) due to recurrent disc herniation. This article is a prospective clinical study. We conducted microdiscectomy and PDTS (using a cosmic dynamic screw-rod system) in 40 cases (23 males, 17 females) with a diagnosis of recurrent disc herniation. Mean age of included patients was 48.92 +/- 12.18 years (range: 21-73 years). Patients were clinically and radiologically evaluated for follow-up for at least two years. Patients' postoperative clinical results and radiological outcomes were evaluated during the 3rd, 12th, and 24th months after surgery. Forty patients who underwent microdiscectomy and PDTS were followed for a mean of 41 months (range: 24-63 months). Both the Oswestry and VAS scores showed significant improvements two years postoperatively in comparison to preoperative scores (p<0.01). There were no significant differences between any of the three measured radiological parameters (alpha, LL, IVS) after two years of follow-up (p > 0.05). New recurrent disc herniations were not observed during follow-up in any of the patients. We observed complications in two patients. Performing microdiscectomy and PDTS after recurrent disc herniation can decrease the risk of postoperative segmental instability. This approach reduces the frequency of failed back syndrome with low back pain and sciatica.

Bilateral late remote cerebellar hemorrhage as a complication of a lumbo-peritoneal shunt applied after spinal arteriovenous malformation surgery

BACKGROUND/OBJECTIVE

Cerebellar hemorrhage is a very infrequent and unpredictable complication of spinal surgery. To the best of our knowledge, cerebellar hemorrhage resulting from the insertion of a lumbo-peritoneal shunt through which cerebrospinal fluid (CSF) is slowly drained has not been documented to date.

METHODS

Case report.

RESULTS

A 47-year-old woman presented with lower extremity weakness. Spinal arteriovenous malformation was diagnosed, and she underwent surgery. Her neurologic status improved; however, CSF collected subcutaneously as a cyst and leaked 21 days after surgery. The patient underwent urgent surgery during which the dural defect was repaired and a lumbo-peritoneal catheter was put in place to treat the CSF leakage. The lumbo-peritoneal drainage system was removed when bilateral cerebellar hemorrhage was seen 12 days later. Physical therapy was stopped, and conservative treatment was initiated consisting of bed rest, analgesics, sedatives, and careful monitoring of blood pressure. The patient's headache gradually resolved; physical therapy was restarted to rehabilitate this patient with paraparesis.

CONCLUSIONS

Remote cerebellar hemorrhage seems to be life threatening and entails significant morbidity. Cerebellar symptoms, and even a late sudden headache after spinal surgery, may be signs of remote cerebellar hemorrhage, which is a rare complication.

The major complications of transpedicular vertebroplasty

OBJECT

Vertebroplasty is a well-known technique used to treat pain associated with vertebral compression fractures. Despite a success rate of up to 90% in different series, the procedure is often associated with major complications such as cord and root compression, epidural and subdural hematomas (SDHs), and pulmonary emboli, as well as other minor complications. In this study, the authors discuss the major complications of transpedicular vertebroplasty and their clinical implications during the postoperative course.

METHODS

Vertebroplasty was performed in 12 vertebrae of 7 patients. Five patients had osteoporotic compression fractures, 1 had tumoral compression fractures, and 1 had a traumatic fracture. Two patients had foraminal leakage, 1 had epidural leakage, 1 had subdural cement leakage, 2 had a spinal SDH, and the last had a split fracture after the procedure.

RESULTS

Three patients had paraparesis (2 had SDHs and 1 had epidural cement leakage), 3 had root symptoms, and 1 had lower back pain. Two of the 3 patients with paraparesis recovered after evacuation of the SDH and subdural cement; however, 1 patient with paraparesis did not recover after epidural cement leakage, despite cement evacuation. Two patients with foraminal leakage and 1 with subdural cement leakage had root symptoms and recovered after evacuation and conservative treatment. The patient with the split fracture had no neurological symptoms and recovered with conservative treatment.

CONCLUSIONS

Transpedicular vertebroplasty may have major complications, such as a spinal SDH and/or cement leakage into the epidural and subdural spaces, even when performed by experienced spinal surgeons. Early diagnosis with CT and intervention may prevent worsening of these complications.

Endoscopic resection of a retroperitoneal schwannoma: case report

INTRODUCTION

Retroperitoneal schwannomas are rare tumors. The symptoms are usually non-specific and these lesions can only be demonstrated with advanced radiological methods. Posterior and anterior approaches can be used to remove retroperitoneal schwannomas. Traditional techniques carry significant risks.

CASE REPORT

A 35-year-old man was admitted with a history of right leg pain of 3 months duration. He had received conservative treatment and physical therapy but none of these measures had been helpful. Findings on physical and neurological examinations were all within normal limits. Magnetic resonance imaging revealed a retroperitoneal mass lesion medial to the right psoas muscle at the level of the S1 vertebra. The tumor was removed using an endoscopic transabdominal approach.

CONCLUSION

The endoscopic transabdominal approach is a safe, efficient and minimally invasive procedure compared to traditional methods also to remove retroperitoneal schwannomas in selected cases.

Utilizing dynamic rods with dynamic screws in the surgical treatment of chronic instability: a prospective clinical study

AIM

In this study, we examined the results of utilizing the agile posterior dynamic stabilization system with dynamic transpedicular screws in our patients.

MATERIAL AND METHODS

Posterior dynamic instrumentation with agile rods and dynamic transpedicular screws was employed in 15 (seven male and eight female) patients (mean age = 42, ranging from 30 to 53). The average follow-up duration was 19 months (ranging from 12 to 25). The primary purpose for the surgery was degenerative disc disease. For subjective evaluation, patients underwent a physical examination utilizing the Oswestry disability index (ODI) and visual analogue scale (VAS). Radiographic parameters, including the angle of lumbar lordosis (LL), angle of segmental lordosis (alpha) and intervertebral space (IVS), were also evaluated. Both subjective patient evaluations and radiographic parameters were assessed at the 3rd and 12th postoperative months.

RESULTS

Significant postoperative improvements were observed in the ODI and VAS measurements (P < 0.05). There were no significant differences in the LL, alpha and IVS parameters. One patient experienced a broken screw.

CONCLUSION

We obtained good clinical results by utilizing dynamic rods with dynamic transpedicular screws.

Prenatal diagnosis of a large, cervical, intraspinal, neurenteric cyst and postnatal outcome

Neurenteric cysts are rare congenital anomalies derived from the notochord and located in front of the spinal column, mostly at the cervical level. They consist of an intraspinal cystic component that is connected to a mediastinal or thoracic cyst. A case of a cervical, intraspinal, neurenteric cyst, diagnosed at 28 weeks of gestation and operated on at 3 and half months after birth, is reported. Herein, we discuss important features of this case including its rare occurrence, intrauterine diagnosis, and early surgical intervention. In conclusion, the nature of prenatal intradural cysts should be fully evaluated and differentiated between neurenteric cyst and other types of cysts with fetal ultrasonography. Therefore, it is essential to be aware of this potential cyst in fetal ultrasonography in utero. Neurenteric cyst should be considered in the differential diagnosis of cervical intradural cystic lesions. In infants, successful surgery provides a cure in patients with cervical neurenteric cysts.

Total disc replacement in the treatment of lumbar discogenic pain with disc herniation: a prospective clinical study

BACKGROUND

Biomechanical benefits of Total Disc Replacement (TDR) including both the restoration of normal segmental range of motion and the prevention of physiological lumbar lordosis encourage spine surgeons to perform TDR for lumbar disc disease.

METHODS

A total of twenty patients (mean age: 39.5) who had degenerative disc disease with unilateral disc herniation were operated on between 2003 and 2006. Microscopic anterior lumbar discectomy with TDR placement via a transperitoneal approach were performed. Each patient was evaluated using a VAS and the Oswestry index.

RESULTS

Mean ODI improved from 73.3 preoperatively to 35.0 and 20.4 at 3 and 12 months of follow-up respectively (P < 0.001). The mean VAS score improved from 8.65 preoperatively to 2.6 and 1.9 at 3 and 12 months respectively (P < 0.001).

CONCLUSIONS

Results from this series are promising and indicate that placement of TDR for degenerative disc disease with lumbar disc herniation is a valuable alternative to conventional techniques. The main advantages of this application are preservation of spinal stability, early mobilization, restoration of normal segmental range of motion and elimination of problems related to intervertebral disc tissue such as discogenic pain and recurrence of disc herniation.

Clinical outcomes following cervical laminoplasty for 19 patients with cervical spondylotic myelopathy

OBJECTIVE

Cervical laminoplasty is an effective procedure. We describe the technique of open-door and french-door cervical laminoplasty and present our clinical results.

METHODS

All patients undergoing laminoplasty at our clinic during the 1997- 2008 period were included in the study. All patients had myeloradiculopathy. Neurological functions and recovery in myelopathy in patients were evaluated using the Nurick score. Pre- and postoperative kyphotic evaluation was measured using the sagittal tangent method. Peri- and postoperative complications were recorded.

RESULTS

Clinical evaluation showed that all patients had reduced postoperative complaints compared to their complaints before the procedure. Average time of surgery was 180 min. Average blood loss in surgeries was 300 cc. According to the Nurick classification, no improvement was observed in seven patients; nine patients showed improvement of one grade; and three patients showed an improvement of two grades. Temporary C5 nerve root paralysis was observed in two patients as a postoperative complication. Complete recovery was observed in both patients within 2 months.

CONCLUSIONS

Laminoplasty is a safe and effective alternative procedure to treat cervical spondylotic myelopathy.

Endoscopic treatment of trans-sellar trans-sphenoidal encephalocele associated with morning glory syndrome presenting with non-traumatic cerebrospinal fluid rhinorrhea

Basal encephaloceles are rare, accounting for about 1.5% of all encephaloceles. The trans-sellar trans-sphenoidal encephalocele variety is the rarest. Morning glory syndrome is often associated with basal encephalocele. Spontaneous cerebrospinal fluid (CSF) rhinorrheas are the least common of these, accounting for only 3% to 5% of all CSF rhinorrheas. The authors describe the outcome of a 10-year follow-up study of a 26-year-old male patient with a spontaneous CSF rhinorrhea occurring trans-sphenoidal encephalocele associated with bilateral morning glory syndrome that was treated with an endoscopic endonasal approach. Endoscopic exploration of the sella floor was performed and closed with abdomen fat packing and muscle fascia. The postoperative course was uneventful. A follow-up magnetic resonance (MR) image at 6 months postoperatively showed extension of encephalocele in the sphenoidal sinus, which was repaired. The patient had no further CSF rhinorrhea and showed no ophthalmologic changes over a follow-up period of over 10 years. Ophthalmologic findings such as strabismus, in association with anomalies of the optic nerve, should alert the physician to the possible presence of an unrecognized skull base midline defect and encephalocele before CSF leakage is seen. The authors believe that a surgeon who has equal confidence in performing the endoscopic endonasal and conventional microscopic trans-sphenoidal approaches should choose the less invasive surgery.

Idiopathic spinal cord herniation: case report and review of the literature

BACKGROUND

Idiopathic spinal cord herniation (ISCH) is a rare cause of progressive myelopathy frequently present in Brown-Séquard syndrome. Preoperative diagnosis can be made with magnetic resonance imaging (MRI). Many surgical techniques have been applied by various authors and are usually reversible by surgical treatment.

METHODS

Case report and review of the literature.

FINDINGS

A 45-year-old woman with Brown-Séquard syndrome underwent thoracic MRI, which revealed transdural spinal cord herniation at T8 vertebral body level. During surgery the spinal cord was reduced and the ventral dural defect was restorated primarily and reinforced with a thin layer of subdermal fat. The dural defect was then closed with interrupted stitches.

RESULTS

Although neurologic status improved postoperatively, postsurgical MRI demonstrated swelling and abnormal T2-signal intensity in the reduced spinal cord. Review of the English language literature revealed 100 ISCH cases.

CONCLUSIONS

ISCH is a rare clinical entity that should be considered in differential diagnosis of Brown-Séquard syndrome, especially among women in their fifth decade of life. Outcome for patients who initially had Brown-Séquard syndrome was significantly better than for patients who presented with spastic paralysis. Although progression of neurologic deficits can be very slow, reduction of the spinal cord and repair of the defect are crucial in stopping or reversing the deterioration.

Single-stage posterior corpectomy and expandable cage placement for treatment of thoracic or lumbar burst fractures

STUDY DESIGN

A prospective study was performed.

OBJECTIVE

To assess an unusual technique for corpectomy and expandable cage placement via single-stage posterior approach in acute thoracic or lumbar burst fractures.

SUMMARY AND BACKGROUND DATA

Burst fractures represent 10% to 20% of all spine injuries at or near the thoracolumbar junction, and can cause neurologic complications and kyphotic deformity. The goal of surgical intervention is to decompress the neural elements, restore vertebral body height, correct angular deformity, and stabilize the columns of the spine.

METHODS

The study comprised 14 patients (8 women and 6 men aged 40.3 years) who had 1 spinal burst fracture between T8 and L4 and who underwent single-stage posterior corpectomy, circumferential reconstruction with expandable-cage placement, and transpedicle screwing between January 2003 and May 2005. Neurologic status was classified using the American Spinal Injury Association (ASIA) impairment scale and functional outcomes were analyzed using a visual analogue scale (VAS) for pain. The kyphotic angle (alpha) and lordotic angle (beta) were measured in the thoracic or thoracolumbar and lumbar regions, respectively. RESULTS.: The mean follow-up time was 24 months (range, 12-48 months). Neurologic status was in 7 patients (preop: ASIA-E, postop: unchanged), 2 patients (preop: ASIA-D, postop: 1 unchanged, 1 improved to ASIA-E), 3 patients (preop: ASIA-C, postop: 2 improved to ASIA-D, 1 improved to ASIA-E), 2 patients (preop: ASIA-B, postop: 1 improved to ASIA-C, 1 unchanged). The mean operative time was 187.8 minutes. The mean blood loss was 596.4 mL. Regarding postoperative complications, 1 patient experienced transient worsening of neurologic deficits and 1 patient developed pseudarthrosis. The mean preoperative VAS score was 8.21 and the mean postoperative VAS score was 2.66 (P < 0.05). The mean preoperative kyphotic angle for the 11 individuals with the thoracic or thoracolumbar burst fractures was 24.6 degrees and the mean preoperative lordotic angle for the 3 individuals with lumbar burst fractures was 10.6 degrees. The corresponding values at 12 months postsurgery were 17.1 degrees and 13.6 degrees.

CONCLUSION

This single-stage posterior approach for acute thoracic and lumbar burst fractures offers some advantages over the classic combined anterior-posterior approach. The results from this small series suggest that a single-stage posterior approach should be considered in select cases.

The combined use of a posterior dynamic transpedicular stabilization system and a prosthetic disc nucleus device in treating lumbar degenerative disc disease with disc herniations

Background

Prosthetic replacement of spinal discs is emerging as a treatment option for degenerative disc disease. Posterior dynamic transpedicular stabilization (PDTS) and prosthetic disc nucleus (PDN) devices have been used sporadically in spinal surgery.

Methods

This was a prospective study of 13 patients averaging 40.9 years of age with degenerative disc disease who underwent posterior placement of a PDN with a PDTS. The Oswestry low-back pain disability questionnaire and visual analog scale (VAS) for pain were used to assess patient outcomes at the 3rd, 6th, and 12th postoperative months.

Lumbar range of motion was evaluated using a bubble inclinometer preoperatively and at 12 months postoperatively. Radiological parameters including lumbar lordosis angle (LL), segmental lordosis angle (α), disc height at the operated level (DHo), and disc height of the adjacent level (DHu) were evaluated. A typical midline posterior approach for complete discectomy was followed by the simultaneous placement of the PDN with PDTS.

Results

Both the Oswestry and VAS scores showed significant improvement postoperatively (P < .05). There were no significant differences in LL, α, DHo, and DHu parameters. We observed complications in 3 patients including 2 patients who had the PDN device embedded into the adjacent corpus; 1 had massive endplate degeneration, and the other experienced interbody space infection. In 1 patient, the PDN device migrated to one side in the vertebral space.

Conclusion

The use of a PDN in combination with posterior dynamic instrumentation can help to restore the physiologic motion of the anterior and posterior column and could help to establish posterior dynamic instrumentation as an important treatment of degenerative disc disease. Theoretically this concept is superior, but practically we need more advanced technology to replace disc material. Because this study examined the combination of the PDN and stabilization instrumention, the results cannot be compared with those reported in the literature for either PDN alone or dynamic screws alone.

Level of Evidence

Prospective cohort study with good follow-up (level 1b).