Vertebral Body Resection Research Articles

Treatment of neoplastic spinal cord compression

Currently, external radiation and steroid therapy are used in most patients with neoplastic spinal cord compression. Surgery is generally used to treat those who do not respond to radiation therapy. To determine the role of de novo surgery in patients with spinal metastases, a prospective study was undertaken. Over a 4 1/2-year period, the cases of 54 patients with radiologically documented spinal metastases were studied. The sites of tumor origin included soft tissue sarcoma (8 patients), kidney (6 patients), lung (5 patients), breast (5 patients), spine (6 patients), unknown primary site (6 patients), and others (18 patients). Sites of compression included the cervical spine segments in 15 patients, thoracic segments in 23, lumbar in 14, and sacral in 2. Before surgery, 24 patients (44%) were nonambulatory. Three surgical approaches were used: anterior vertebral body resection in 45 patients, laminectomy in 7, and lateral osteotomy in 2. After surgery, 37 patients received external radiation therapy. All patients improved (became ambulatory) after surgery, with 23 of 25 patients surviving at 2 years continuing to be ambulatory. The 30-day mortality rate was 6% (three patients); eight patients (15%) sustained various surgical complications. These results are superior to those reported after external radiation therapy and steroids alone, and they support the concept that de novo surgery be considered in selected patients with spinal metastases.

Epidural spinal cord compression: Treatment options

Abstract The appropriate management of patients with metastatic disease to the spine demands a comprehensive evaluation and decision-making process on the part of the orthopedic surgeon. Each patient must be considered separately, taking into consideration all possible factors, especially the individual's medical status and longevity. While the classification systems presented are far from encompassing, they may serve as treatment guidelines. As the medical treatment of cancer improves, more patients are surviving longer, and, therefore, developing an increasing number of metastatic complications. Surgical intervention should be reserved for those cases in which nonoperative measures have little chance of succeeding or already have failed. When warranted, decompressive procedures are best accomplished by first assessing the location of compression. The indiscrimate use of laminectomy in the past has lead to poor results reported in earlier surgical series. Anterior vertebral body resections with stabilization techniques have led to improved satisfactory outcome. An aggressive approach to these patients remains justifiable in those individuals with an expected longevity of more than 3 to 6 months in order to assure an improved quality of remaining time.

Tumors of the Thoracic and Lumbar Spine

We are reporting our experience in 23 patients with tumors of the thoracic or lumbar vertebrae treated via surgical anterior decompression and stabilization. Seventeen patients had metastatic disease and were treated with vertebral body resection followed by stabilization with anterior polymethylmethacrylate and threaded Harrington rods with sacral distraction hooks. Six patients had primary tumors and, following tumor resection and partial vertebral body resection, had autogenous bone graft struts placed anteriorly as well as posterior instrumentation. Posterior instrumentation was transpedicular one level above and below in the lumbar spine, and segmental hooks and rods three levels above and below in the thoracic spine. Nineteen patients presented with severe unremitting pain, and 16 had neurologic deficits, including 7 who were unable to ambulate. Radiation therapy was used as an additional treatment and routinely begun 2 weeks postoperatively. All patients survived the surgery, and none had neurologic deterioration immediately postoperatively. Eight patients had died at the time of review. The mean survival was 14 months and ranged from 6 to 38 months. Of the surviving patients, follow-up ranged from 24 to 40 months with an average follow-up of 30 months. Pain relief was excellent in all but two patients (93%). Motor recovery occurred to some extent in all patients, and only one remained nonambulatory. Complications were minor in three patients (13%) and major in one (4%). Tumor recurrence with neurologic deterioration occurred in two patients. We are very encouraged by these results, and we recommend that patients with tumors of the vertebral body with neurologic deficit or severe unremitting pain be studied with MRI and/or myelography and CT. The patients with gross vertebral destruction and greater than 50% collapse of the vertebral body, those in need of a tissue diagnosis, or those with major neurologic deficit can be effectively treated by anterior decompression and stabilization.

Flexible device for vertebral body replacement

A novel vertebral prosthesis is presented. The prosthesis was developed for surgical procedures requiring the resection of a complete vertebral body and the adjacent intervertebral discs, the design objective being to develop a flexible implant that would be robust enought to withstand the in vivo stress environment of the human spine. In theory, a flexible implant should preserve a more normal range of motion and apply less stress to surrounding tissue than a rigid implant. A prototype implant was constructed so as to combine a rigid stainless steel structure with flexible silicon rubber elements in order to form an implant with static and dynamic mechanical characteristics similar to those of the anterior spinal column. Implant flexibility characteristics were determined from ex vivo stress-strain behaviour during bending and compressive creep testing. Results from the bending tests indicated good agreement for the lateral and sagittal bending characteristics in comparison with in vitro bending tests of human lumbar motion segments. Comparison of the implant compressive creep responsé with similar in vitro tests on human lumbar intervertebral discs also demonstrated similarities in the time-dependent mechanical parameters.

Current considerations in the management of neoplastic spinal cord compression.

Nearly 20% of patients with neoplastic involvement of the vertebral column develop spinal cord compression, and in 8% this is the initial manifestation of cancer. Important determinants of functional prognosis are: 1) tumor biology, 2) pretreatment neurologic status, and 3) tumor location within the spinal canal and the therapy employed. Future efforts should be invested in manipulation of the last two determinants. Delay in neurologic deterioration may be achieved by pharmacologic manipulation of the deleterious pathophysiologic processes operating in the compressed spinal cord, as recently demonstrated in experimental animal models. Use of modern neuro-imaging techniques (metrizamide myelography combined with computed tomography, and/or magnetic resonance imaging) will accurately define tumor extent and location. Radiotherapy is indicated in highly or moderately radiosensitive tumors. Surgery is reserved for the following situations: diagnosis in doubt, previous radiation exposure, radioresistant tumors, neurologic deterioration during irradiation, and the presence of spinal instability or bone compression of the neural structures. The location of the compressing tumor will dictate the surgical approach--a vertebral body resection in an anterior or anterolateral tumor and a laminectomy in a posterior or posterolateral deposit. Modern instrumentation techniques for spinal column stabilization or vertebral body replacement will allow immediate painless ambulation and a better quality of life for these patients.

Anterior and posterior stabilization of the spine following vertebral body resection. A postmortem investigation.

Postmortem examination of a spine, which had been instrumented anteriorly at one level and posteriorly at another following vertebral body resections, showed that the posterior instrumentation was more effective in resisting torsion. Postmortem examination of a second case, where the anterior fixation had been strengthened by the addition of cement studs in the vertebral end-plates and a paravertebral modified and strengthened Zielke screw/rod system, showed this second anterior system to be an improvement for resisting torsion following the resection of one vertebral body. Anterior interbody devices become enveloped in a firm smooth fibrous capsule. A preliminary experiment on a cadaver spine had shown that anterior interbody fixation was better than posterior instrumentation for resisting flexion-compression forces.

Treatment of neoplastic epidural cord compression by vertebral body resection and stabilization.

The results of treatment of neoplastic spinal cord compression by vertebral body resection and immediate stabilization in 101 consecutive patients over a 5-year period have been analyzed. Sites of primary cancer included the lung (25 patients), kidney (15 patients), breast (14 patients), connective tissue (12 patients), and a variety of others (35 patients). Of the 101 patients, 23 received surgery de novo; the remaining 78 patients had undergone previous therapy. Sites of involvement included the cervical region in 13 patients, the thoracic region in 68 patients, and the lumbar region in 20 patients. Prior to surgery, severe pain was noted in 90% of the patients, and 45% were non-ambulatory. Using an anterolateral surgical exposure, the vertebral body was resected along with all epidural tumor. Immediate stabilization was achieved with methyl methacrylate and Steinmann pins. Following surgery, the overall ambulation rate was 78%, and 85% of patients experienced pain relief. Of the 23 patients who had received no prior therapy, 90% continued to be ambulatory at their last follow-up examination or until death. The authors believe that surgery prior to irradiation is indicated in selected patients with neoplastic cord compression. In patients with solitary osseous metastasis to the spine, potentially curative resection can be undertaken if surgery is performed when the tumor is still confined to the vertebral body.

Surgical decompression of anterior and posterior malignant epidural tumors compressing the spinal cord: a prospective study.

Of 167 episodes of spinal epidural neoplastic compression, 86 were treated by operation. The surgical approach was prospectively selected according to the location of the tumor in the spinal canal. Decompression was achieved by 61 vertebral body resections (VBRs) and by 25 laminectomies. The indications for operation were: neurological relapse after previous radiotherapy, the need to make a tissue diagnosis, a radioresistant tumor, and neurological deterioration during radiotherapy. Before VBR, 28% (17 of 61) were still able to walk, 51% (31 of 61) were parAparetic, and 21% (13 of 61) were paraplegic. Bowel and bladder dysfunction was present in 49% (30 of 61). After VBR, the outcome of only 57 procedures was available for evaluation because of the postoperative death of 4 patients. Eighty per cent (46 of 57) were able to walk, 18% (10 of 57) were paraparetic, and 2% (1 of 57) were paraplegic. Ninety-three per cent had normal sphincter control. Before laminectomy, 8% (2 of 25) were ambulatory, 84% (21 of 25) were paraparetic, and 8% (2 of 25) were paraplegic. Bowel and bladder dysfunction was present in 76% (19 of 25). After laminectomy, only 23 procedures were evaluated because of the postoperative death of 2 patients. Thirty-nine per cent (9 of 23) were ambulatory, 35% (8 of 23) were paraparetic, and 26% (6 of 23) were paraplegic. Fifty-seven per cent regained normal sphincter control. The operative mortality was 7% (4 of 61) in VBR and 8% (2 of 25) in laminectomy.(ABSTRACT TRUNCATED AT 250 WORDS)

Vertebral body resection for epidural compression by malignant tumors. Results of forty-seven consecutive operative procedures.

We are presenting our experience with vertebral body resection in forty-seven operative procedures in forty patients with a malignant epidural tumor. The indication for surgery was neural relapse after previous radiotherapy in eighteen procedures, the need for a tissue diagnosis in sixteen, a radioresistant tumor in seven, neural deterioration while receiving radiotherapy in five, and a pathological fracture-dislocation in one. In thirty-three procedures (70 per cent) the level of compression was in the thoracic spine. Replacement of the resected vertebral bodies was achieved by anterior instrumentation and the use of methylmethacrylate in twenty-one procedures (45 per cent), while bone-grafting, cement, and instrumentation in various combinations were used in the remainder. Before surgery all of the patients had some neural deficit. The patient was still able to walk prior to twelve (26 per cent) of the procedures, was paraparetic prior to twenty-three (49 per cent), and was paraplegic prior to twelve (26 per cent). Bowel and bladder dysfunction was present before twenty-five (53 per cent). The outcome of only forty-four procedures could be evaluated because three patients died postoperatively. The patient was able to walk following thirty-five (80 per cent) of the procedures, was paraparetic after eight (18 per cent), and was still paraplegic after one. The patient regained normal sphincter control after forty-one (93 per cent) of the procedures. Three (6 per cent) of the procedures were followed by the death of the patient, and complications occurred after five (11 per cent) of the procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Fractured Steinmann Threaded Fixation Pins Following Vertebral Body Resection and Stabilization: Medical Device Pathological Analysis of Two Cases

ABSTRACTVertebral body resection in the treatmenL of metastatic neoplasms of the spine is increasingly common for radioresistant tumors. It is also favored for treating progressive neurological disease due to tumor-associated spinal cord compression. Spine stabilization following resection is accomplished by several techniques. Increasing in popularity is the combination of threaded fixation pins and methylmethacrylate filler.In the two cases reported in this communication, failure of threaded AISI 316 stainless steel pins occured through corrosion fatigue. Corrosion begins at the base of the threads and is exacerbated by galvanic cell formation at the methyl methacrylate-bone interface. Fatigue is experienced because the cervical and vertebral bodies are each a part of a joint that normally experiences 10 – 20 degrees of both antero-posterior and lateral flexion.We conclude that in active patients, non-threaded cobalt chrome pins are the preferred material for stabilization of the lumbar and cervical spine following vertebral body resections.

Technique of Cervical Interbody Fusion

A dovetail autogeneic graft is demonstrated for anterior interbody fusion of the cervical spine for degenerated or protruded intervertebral discs. The method is applicable for one or more levels and has been successfully combined with vertebral body resection for metastatic tumors and trauma. The procedure provides secure initial interbody immobilization and prevents interbody collapse. None of the 58 cases had grafts slip from their original position. The union rate has been 100%.

Reconstruction of the cervical spine following anterior vertebral body resection: a mechanical analysis of a canine experimental model.

In some quadriplegic patients whose acute spinal injury consists of a vertebral body fracture with bony retropulsion anteriorly and ligamentous damage posteriorly, it is appropriate to perform a decompression of the injured spinal cord by excision of the fractured body. Reconstruction of such a spine to achieve immediate and ultimate stability can be quite difficult. This is a report of mechanical testing using a canine in vitro experimental model to simulate different general types of reconstruction systems applicable to the spine destabilized as above. The results explain some of the previously noted failures of the traditional anterior strut grafting procedures. In addition, one of the reconstruction systems tested (anterior and posterior tension bands compressing an anterior strut graft into place) appeared to have sufficient immediate stability to eliminate the need for a halo-vest in the postoperative period. If such a reconstruction system were to prove clinically applicable, it would be quite beneficial to the quadriplegic patient in his rehabilitation.

Vertebral body resection in the treatment of cancer involving the spine.

Results of radical spinal surgery with vertebral body resection in of 51 patients with primary and metastatic cancer of the spine were analyzed. Seven patients had primary spine tumors, 16 had paravertebral tumors that involved the spine by direct extension, and 28 had blood-borne metastases to the spine. Thirty-five patients (68%) had prior therapy directed to the spine: 4 had undergone previous surgery, 9 had surgery and radiation, and 22 had radiation alone. Forty-five patients (90%) had intractable pain, and 25 patients (48%) were nonambulatory. Myelography revealed high-grade or complete block in 39 patients (76%). Following surgery, 38 of 45 (84%) had pain relief, and 40/58 (78%) were ambulatory at discharge. Of the 25 patients who were unable to walk prior to surgery, 15 (60%) improved to fully ambulatory status. The surgical mortality was low (4%), and complications were few (10%). These results are superior to those reported following treatment by radiation and steroid therapy. In selected patients who have actual or potential neural compression resulting from tumor within the vertebral body, such surgery should be considered as initial therapy.

Treatment of spinal metastases by vertebral body resection.

(1984). Treatment of Spinal Metastases by Vertebral Body Resection. Cancer Investigation: Vol. 2, No. 5, pp. 383-397.

Anterior cervical vertebral body resection and bone-grafting for benign and malignant tumors. A survey under the auspices of the Cervical Spine Research Society.

Anterior cervical vertebral body resection and bone-grafting for benign and malignant tumors. A survey under the auspices of the Cervical Spine Research Society.

Congenital Kyphosis in Myelomeningocele

The deforming mechanisms in the congenital lumbar kyphosis of myelomeningocele are situated anteriorly. Posterior wedge resection with local fusion therefore will not prevent progression of the deformity. Nonetheless, this procedure may be the only method of affording sac closure, or providing continuity of the ulcerated integument. Definitive corrective surgery will be required later and must combat the anterior deforming forces. Resection of the apical vertebral body followed by posterior fusion with Harrington instrumentation provides a solid straight spine.

Hyperlordosis Caused by the Lumboperitoneal Shunt Procedure for Hydrocephalus

A case of severe lumbar lordosis, caused by repeated lumbopenitoneal shunts, is presented with surgical correction of the deformity by anterior wedge resection of vertebral bodies and discs, and spine fusion. The possibility of the development of severe lumbar lordosis secondary to surgical exposure of the lumbar vertebra during a lumboperitoneal shunt procedure is suggested as the etiological factor. Alternatives to this shunt procedure should be utilized if possible.