The role of vertebral body collapse in the management of malignant spinal cord compression

Minimal invasive fixation following with radiotherapy for radiosensitive unstable metastatic spine

BACKGROUND

Minimally invasive surgery (MIS) has become a feasible option for patients with spinal metastasis, but the effectiveness of percutaneous pedicle screw fixation (PPSF) without decompression in patients with severe cord compression remains unknown. We compared PPSF without decompression with debulking surgery in patients with radiosensitive, unstable, metastatic thoracolumbar spinal cord compression.

METHODS

A retrospective study of surgically treated spinal metastasis and spinal cord compression patients was conducted between October 2014 and June 2019. Demographic and pre- and postoperative data were collected and compared between patients treated with minimally invasive percutaneous fixation and external beam radiotherapy (EBRT) (the PPSF group) and those treated with debulking surgery (the debulking group).

RESULTS

We included 50 patients in this study. The PPSF group had a significantly shorter operative time (143.56 ± 49.44 min vs. 181.47 ± 40.77 min; p < .01), significantly lower blood loss (116.67 ± 109.92 mL vs. 696.55 ± 519.43 mL; p < .01), and significantly shorter hospital stay (11.90 ± 9.69 vs. 25.35 ± 20.65; p <0.01) than did the debulking group. No significant differences were observed between the groups in age, sex, spinal instability neoplastic score, ESCC, Tomita scores, numeric rating scale scores, American Spinal Injury Association Impairment Scale scores, survival rates, and complication rates. Postoperative neurologic function and decrease in pain were similar between the groups.

CONCLUSION

The PPSF group had a shorter operation time, shorter length of hospital stay, and less blood loss than did the debulking group. PPSF followed by EBRT is pain relieving, relatively safe and appropriate as palliative therapy.

Management - spinal metastases

Due to a worldwide increase of cancer incidence and a longer life expectancy of patients with metastatic cancer, a rise in the incidence of symptomatic vertebral metastases has been observed. Metastatic spinal disease is one of the most dreaded complications of cancer as it is not only associated with severe pain, but also with paralysis, sensory loss, sexual dysfunction, urinary and fecal incontinency when the neurologic elements are compressed. Rapid diagnosis and treatment have been shown to improve both the quality and length of remaining life. This chapter on vertebral metastases with epidural disease and intramedullary spinal metastases will be discussed in terms of epidemiology, pathophysiology, demographics, clinical presentation, diagnosis, and management. With respect to treatment options, our review will summarize the evolution of conventional palliative radiation to modern stereotactic body radiotherapy for spinal metastases and the surgical evolution from traditional open procedures to minimally invasive spine surgery. Lastly, we will review the most common clinical prediction and decision rules, framework and algorithms, and guidelines that have been developed to guide treatment decision making.

Management of Metastatic Spinal Cord Compression

Metastatic spinal cord compression, diagnosed in 3–7% of cancer patients, is one of the most dreaded complications of metastatic cancer. It is an oncologic emergency, which must be diagnosed early and treated promptly to achieve the best results and avoid progressive pain, paralysis, sensory loss and sphincter incontinence. Patients who are ambulatory at the time of the diagnosis have a higher probability of obtaining good response to treatment and a longer survival. In clinical practice, back pain accompanies metastatic spinal cord compression in most cases, even in patients with no neurologic deficits. Magnetic resonance imaging is the best tool for diagnosing metastatic spinal cord compression and is able to identify spinal cord compression in 32–35% patients with back pain, bone metastases and normal neurologic examination. Moreover, magnetic resonance imaging gives the extension of the lesion, can diagnose other unsuspected clinical metastatic spinal cord compression sites, and is useful for the radiation oncologist in defining the target volume. Radiotherapy is the treatment of choice in most cases, whereas surgery is advised only in selected patients (ie, if stabilization is necessary, if radiotherapy has already been given in the same area, when vertebral body collapse causes bone impingement on the cord or nerve roots, when there are diagnostic doubts, or when computed tomography-guided percutaneous vertebral biopsy cannot be performed). Laminectomy should be abandoned in favor of more aggressive surgery (ie, posterior, anterior, and/or lateral approach, tumor mass resection, and stabilization of the spine). Generally, radiotherapy must be administered 7–10 days after surgery. The optimal radiation schedule has not been defined. However, as recently suggested by some clinical trials, even the hypofractionated radiotherapy regimens are effective and can be used without increasing radiation-induced myelopathy. Moderate doses of dexamethasone should be used in the early phases of therapy. After radiotherapy, spinal recurrence is generally found in sites different from the first compression area. A close post-treatment follow-up is suggested using clinical parameters (pain, motor and sphincter function), and magnetic resonance imaging should be performed only when a second metastatic spinal cord compression and/or myelopathy are clinically suspected.

Surgery for metastatic spine tumors in the elderly. Advanced age is not a contraindication to surgery!

BACKGROUND

With recent advances in oncologic treatments, there has been an increase in patient survival rates and concurrently an increase in the number of incidence of symptomatic spinal metastases. Because elderly patients are a substantial part of the oncology population, their types of treatment as well as the possible impact their treatment will have on healthcare resources need to be further examined.

PURPOSE

We studied whether age has a significant influence on quality of life and survival in surgical interventions for spinal metastases.

STUDY DESIGN

We used data from a multicenter prospective study by the Global Spine Tumor Study Group (GSTSG). This GSTSG study involved 1,266 patients who were admitted for surgical treatments of symptomatic spinal metastases at 22 spinal centers from different countries and followed up for 2 years after surgery.

PATIENT SAMPLE

There were 1,266 patients recruited between March 2001 and October 2014.

OUTCOME MEASURES

Patient demographics were collected along with outcome measures, including European Quality of Life-5 Dimensions (EQ-5D), neurologic functions, complications, and survival rates.

METHODS

We realized a multicenter prospective study of 1,266 patients admitted for surgical treatment of symptomatic spinal metastases. They were divided and studied into three different age groups: <70, 70-80, and >80 years.

RESULTS

Despite a lack of statistical difference in American Society of Anesthesiologists (ASA) score, Frankel neurologic score, or Karnofsky functional score at presentation, patients >80 years were more likely to undergo emergency surgery and palliative procedures compared with younger patients. Postoperative complications were more common in the oldest age group (33.3% in the >80, 23.9% in the 70-80, and 17.9% for patients <70 years, p=.004). EQ-5D improved in all groups, but survival expectancy was significantly longer in patients <70 years old (p=.02). Furthermore, neurologic recovery after surgery was lower in patients >80 years old.

CONCLUSIONS

Surgeons should not be biased against operating elderly patients. Although survival rates and neurologic improvements in the elderly patients are lower than for younger patients, operating the elderly is compounded by the fact that they undergo more emergency and palliative procedures, despite good ASA scores and functional status. Age in itself should not be a determinant of whether to operate or not, and operations should not be avoided in the elderly when indicated.

Survival and clinical outcomes in patients with metastatic epidural spinal cord compression after spinal surgery: a prospective, multicenter, observational cohort study

Background

High quality studies have been challenging to undertake in patients with metastatic epidural spinal cord compression. Nonetheless, in the article “Survival and Clinical Outcomes in Surgically Treated Patients With Metastatic Epidural Spinal Cord Compression: Results of the Prospective Multicenter AOSpine Study” recently published in the Journal of Clinical Oncology, our team provided convincing evidence that spinal surgery improves overall quality of life in patients with this potentially devastating complication of cancer. Considering that metastatic spinal lesions treated with surgery have the highest mean cost among all oncological musculo-skeletal issues, it is essential to provide high quality data to optimize the therapeutic approaches and cost-effective use of health care resources.

Main body

Although the AOSpine Study provided high quality prospective data, it was primarily limited by the lack of non-operative controls and the relatively small sample size. Given the dearth of medical equipoise and the fundamental difference between patients deemed to be adequate surgical candidates and those who are not amenable to operative intervention, conducting a randomized controlled trial in this patient population was not felt to be ethically or medically feasible. Consequently, the optimal option to overcome limitations of both the lack of controls and the relatively small sample size is through collection of large prospective datasets through rigorously developed and maintained registries.

Conclusions

With the alarming increase in the incidence of cancer in China and China’s parallel growing cancer control efforts, China would offer a fantastic platform to set up a national metastatic spinal lesion registry. Such registry would not only enhance metastatic epidural spinal cord compression translational research but also optimize patient care.

Cost-effectiveness of surgery in the management of metastatic epidural spinal cord compression: a systematic review

STUDY DESIGN

Systematic review.

OBJECTIVE

To perform an evidence-based synthesis of the literature to examine the cost-effectiveness of surgery in the management of metastatic epidural spinal cord compression (MESCC).

SUMMARY OF BACKGROUND DATA

Between 2.5% and 10% of patients with cancer develop symptomatic MESCC, which leads to significant morbidity, and a reduction in quality and length of life. Although surgery is being increasingly used in the management of MESCC, it is unclear whether this modality is cost-effective, given the relatively limited lifespan of these patients.

METHODS

Numerous databases were searched to identify full economic studies based on key questions established a priori. Only economic studies that evaluated and synthesized the costs and consequences (i.e., cost-minimization, cost-benefit, cost-effectiveness, or cost-utility) were considered for inclusion. Two independent reviewers examined the full text of the articles meeting inclusion criteria to obtain the final cohort of included studies. The Quality of Health Economic Studies instrument was scored by 2 independent reviewers.

RESULTS

The search strategy yielded 38 potentially relevant citations, 2 of which met the inclusion criteria. One was a cost-utility study and the other was a cost-effectiveness study, and both used clinical data from the same randomized controlled trial. Both studies found surgery plus radiotherapy to be not only more expensive but also more effective than radiotherapy alone in the management of patients with MESCC.

CONCLUSION

There is evidence from 2 high-quality studies that surgery plus radiotherapy is costlier but clinically more effective than radiotherapy alone for the management of MESCC. Of note, cost-effectiveness data for the role of spinal stabilization in the management of oncological spinal instability are lacking. This is a key knowledge gap that represents an opportunity for future research.

The role of radiotherapy for metastatic epidural spinal cord compression

Radiotherapy alone is the most common treatment for metastatic epidural spinal cord compression (MESCC). Decompressive surgery followed by radiotherapy is generally indicated only in 10-15% of MESCC cases. Chemotherapy has an unclear role and may be considered for selected patients with hematological or germ-cell malignancies. If radiotherapy alone is given, it is important to select the appropriate regimen. Similar functional outcomes can be achieved with short-course radiotherapy regimens and longer-course radiotherapy regimens. Longer-course radiotherapy is associated with better local control of MESCC than short-course radiotherapy. Patients with a more favorable survival prognosis (expected survival of ≥6 months) should receive longer-course radiotherapy, as they may live long enough to develop a recurrence of MESCC. Patients with an expected survival of <6 months should be considered for short-course radiotherapy. A recurrence of MESCC in the previously irradiated region after short-course radiotherapy may be treated with another short-course of radiotherapy. After primary administration of longer-course radiotherapy, decompressive surgery should be performed if indicated. Alternatively, re-irradiation can be performed using high-precision techniques to reduce the cumulative dose received by the spinal cord. Larger prospective trials are required to better define the appropriate treatment for the individual patient.

[Palliative radiation of bone metastasis in the spine for symptom control and stabilisation: indication and limits]

On the basis of a case study the success of palliative radiation of metastasis of a non-small-cell lung cancer in the spine is demonstrated and the limits of this palliative therapy are discussed. Pain control seems to be the first aim, stabilisation of the spine and myelodecompression to prevent paraplegia could be another.

Short-Course Versus Split-Course Radiotherapy in Metastatic Spinal Cord Compression: Results of a Phase III, Randomized, Multicenter Trial

Purpose

Hypofractionated radiotherapy (RT) is often used in the treatment of metastatic spinal cord compression (MSCC). This randomized trial was planned to assess the clinical outcome and toxicity of two different hypofractionated RT regimens in MSCC.

Patients and Methods

Three hundred patients with MSCC were randomly assigned to a short-course RT (8 Gy × 2 days) or to a split-course RT (5 Gy × 3; 3 Gy × 5). Only patients with a short life expectancy entered the protocol. Median follow-up was 33 months (range, 4 to 61 months).

Results

A total of 276 (92%) patients were assessable; 142 (51%) treated with the short-course and 134 (49%) treated with the split-course RT regimen. There was no significant difference in response, duration of response, survival, or toxicity found between the two arms. When short- versus split-course regimens were compared, after RT 56% and 59% patients had back pain relief, 68% and 71% were able to walk, and 90% and 89% had good bladder function, respectively. Median survival was 4 months and median duration of improvement was 3.5 months for both arms. Toxicity was equally distributed between the two arms: grade 3 esophagitis or pharyngitis was registered in four patients (1.5%), grade 3 diarrhea occurred in four patients (1.5%), and grade 3 vomiting or nausea occurred in 10 patients (6%). Late toxicity was never recorded.

Conclusion

Both hypofractionated RT schedules adopted were effective and had acceptable toxicity. However, considering the advantages of the short-course regimen in terms of patient convenience and machine time, it could become the RT regimen of choice in the clinical practice for MSCC patients.

Clinical trials and evidence-based medicine for metastatic spine disease

Treatment of metastatic epidural spinal disease has undergone significant changes over the last 20 years. No longer is indiscriminate decompressive laminectomy offered as the only surgical treatment. It carries all the risks associated with an invasive procedure and offers the patient little benefit unless it is used to remove disease isolated to the posterior elements. The existing literature suggests that surgery that frees the spinal cord at the site of compression in addition to reconstructing and stabilizing the spinal column is more effective at preserving and regaining neural function, notably ambulatory function and sphincter function, than conventional radiotherapy. It is also highly effective in relieving pain. The preliminary results ofa recent RCT provide the first class I evidence to support a reversal in the current philosophy of primary treatment for many patients with meta-static disease. Conventional radiotherapy has a clearly defined role as adjuvant therapy and as primary therapy in those who are unable to tolerate or benefit significantly from surgery. The role of nonconventional radiation therapy, such as IMRT and SRS, remains to be elucidated.

Anterior spinal arthrodesis with structural cortical allografts and instrumentation for spine tumor surgery

STUDY DESIGN

The authors report on anterior vertebral reconstruction following tumor resection with use of fresh-frozen, cortical, long-segment allografts prepared from diaphyseal sections of long bones. A retrospective analysis of clinical outcomes is presented.

OBJECTIVE

To analyze the results following the use of cortical allografts in the treatment of spine tumors.

SUMMARY OF BACKGROUND DATA

Metastatic disease and primary spinal bone tumors may result in progressive vertebral collapse, instability, deformity, pain, and neurologic deficit. Controversy as to the appropriate type of anterior reconstruction and/or graft material persists.

METHODS

From 1995 until 2001, 30 patients with primary spinal bone tumors or metastases to the spine were treated by anterior vertebral reconstruction with fresh-frozen cortical bone allografts. Grafts were used in combination with anterior and posterior instrumentation.

RESULTS

The median survival was 14 months. Ninety-three percent of all allografts were radiographically incorporated as early as 6 months after surgery in spite of adjuvant chemotherapy and radiation therapy. Fourteen patients (46%) had intraoperative or postoperative complications. Two patients underwent revision surgery for local recurrence. There were no allograft infections, fractures, or collapse.

CONCLUSION

Anterior column reconstruction with structural cortical allografts proved to be a reliable technique in patients with spine tumors. Postoperative complications can often be successfully managed.

Treatment of metastatic spinal epidural disease: a review of the literature

OBJECT

Spinal cord compression is one of the most dreaded complications of metastatic cancer. It can lead to a number of sequelae, including pain, spinal instability, neurological deficits, and a reduction in the patient's quality of life. Except in selected circumstances, treatment is palliative. Treatment options include surgery, radiation, and chemotherapy. The goal of this study was to summarize the existing data on the outcomes of various treatment methods for metastatic spinal epidural disease and to make appropriate recommendations for their use.

METHODS

The authors used a search strategy that included an electronic database search, a manual search of journals, analysis of bibliographies in relevant review papers, and consultation with the senior author. There is good evidence, including Class I data, that steroid drugs constitute a beneficial adjunctive therapy in patients with myelopathy from epidural compression. Historically, conventional radiation therapy has been viewed as the first-line treatment because it has been shown to be as effective as a decompressive laminectomy, with a lower incidence of complications (Class II data). Nevertheless, in the last 20 years there has been remarkable progress in surgical techniques and technology. Currently, the goals of surgery are to achieve a circumferential decompression of the spinal cord, and to reconstruct and immediately stabilize the spinal column. Results in a large body of literature support the belief that surgery is better at retaining or regaining neurological function than radiation and that surgery is highly effective in relieving pain. Most of the data on the treatment of metastatic spinal disease are Class II or III, but the preliminary results of a well-designed, randomized controlled trial in which surgery is compared with standard radiation therapy represents the first Class I data.

CONCLUSIONS

As the number of treatment options for metastatic spinal disease has grown, it has become clear that effective implementation of these treatments can only be achieved by a multidisciplinary approach.

Spinal cord decompression: an endoscopically assisted approach for metastatic tumors

STUDY DESIGN

The paper describes a technique for complete vertebrectomy and spinal cord decompression, followed by a formal anterior column reconstruction, using endoscopic instruments. This procedure is indicated for patients with radioresistant metastasis of the thoracic spine, particularly those involving the upper thoracic segments where a thoracotomy is difficult and carries a high morbidity, and for patients with pulmonary disease who cannot tolerate a standard thoracotomy. Results in nine consecutive cases are reported.

OBJECTIVES

To demonstrate the feasibility and benefits of endoscopically assisted decompression and stabilization through a single, extrapleural, posterolateral approach.

SETTING

The Cleveland Clinic, Cleveland, Ohio, USA.

METHODS

Posterolateral decompression of the thoracic spinal cord offers potential advantages over traditional combined procedures (anterior thoracotomy and posterior instrumentation), including reduced operative time, decreased morbidity, and reduced hospital stay. Previous studies have not demonstrated the same neurological benefit for posterolateral decompression as for anterior vertebrectomy and decompression, however, Surgical indications, rationale and technique for an improved posterolateral approach, augmented by endoscopic methods, are provided, and initial clinical results are described.

RESULTS

Drawbacks to the traditional posterolateral decompressions have included poor visualization of the spinal cord and anterior tumor, poor access to tumor on the side contralateral to the approach, and the need to manipulate the spinal cord to completely remove both adjacent tumor and tumor adherent to the dura. Transpedicular decompression using endoscopy is described in nine patients. The mean operative time for the combined procedure was 6.0 h, with a mean blood loss of 1677 cc. Neurological recovery and maintenance were excellent. Inpatient days averaged 6.5, and ICU days averaged 1.4. Two patients died of disease eight and 14 months post-op, and seven were living, with disease, 3-36 months after surgery.

CONCLUSIONS

Endoscopically assisted decompression can reduce morbidity, hospitalization, and treatment costs while matching the efficacy of traditional combined procedures. Endoscopy provides a readily available and easily applied tool that dramatically improves the surgeon's vision, providing light, magnification, and a direct view of remote structures.

Radiation-induced myelopathy in long-term surviving metastatic spinal cord compression patients after hypofractionated radiotherapy: a clinical and magnetic resonance imaging analysis

BACKGROUND AND PURPOSE

Hypofractionated radiotherapy is often administered in metastatic spinal cord compression (MSCC), but no studies have been published on the incidence of radiation-induced myelopathy (RIM) in long-term surviving patients. Our report addresses this topic.

PATIENTS AND METHODS

Of 465 consecutive MSCC patients submitted to radiotherapy between 1988 and 1997, 13 live patients (seven females, six males, median age 69 years, median follow-up 69 months) surviving for 2 years or more were retrospectively reviewed to evaluate RIM. All patients underwent radiotherapy. Eight patients underwent a short-course regimen of 8 Gy, with 7 days rest, and then another 8 Gy. Five patients underwent a split-course regimen of 5 Gy x 3, 4 days rest, and then 3 Gy x 5. Only one patient also underwent laminectomy. Full neurological examination and magnetic resonance imaging (MRI) were performed.

RESULTS

Of 12 patients submitted to radiotherapy alone, 11 were ambulant (eight without support and three with support) with good bladder function. In nine of these 11 patients, MRI was negative; in one case MRI evidenced an in-field relapse 30 months after the end of radiotherapy, and in the other, two new MSCC foci outside the irradiated spine. In the remaining patient RIM was suspected at 18 months after radiotherapy when the patient became paraplegic and cystoplegic, and magnetic resonance images evidenced an ischemic injury in the irradiated area. The only patient treated with surgery plus postoperative radiotherapy worsened and remained paraparetic. Magnetic resonance images showed cord atrophy at the surgical level, explained as an ischemic necrosis due to surgery injury.

CONCLUSIONS

On the grounds of our data regarding RIM in long-term surviving MSCC patients, we believe that a hypofractionated radiotherapy regimen can be used for the majority of patients. For a minority of patients, more protracted radiation regimens could be considered.

Radiation therapy of metastatic spinal cord compression. Multidisciplinary team diagnosis and treatment

PURPOSE

To evaluate the effectiveness of a multidisciplinary approach to spinal cord compression (SCC) in accordance with prospective protocol, providing a uniform approach to diagnosis, decision making concerning optimal treatment modality in any particular case of SCC, treatment performance and evaluation of treatment results. The SCC patients treated by radiation therapy are described.

MATERIALS AND METHODS

Patients with SCC were examined and treated by a multidisciplinary team consisting of a neurologist, radiologist, oncologist, orthopedic surgeon, and neurosurgeon. Seventy-nine patients for whom radiation was recommended received a 30 Gy radiation dose to a compression-causing mass and course of high dose dexamethasone. Three fractions of 5 Gy and 5 fractions 3 Gy each were delivered by Co60 or 8 MV photon beam in 12 days. Treatment outcome was essentially evaluated by ambulation capabilities which were considered to be the main problem of SCC. Changes in other neurologic motor, sensory and autonomic disturbances were also evaluated.

RESULTS

Seventy-two percent of the patients were already non-ambulatory at diagnosis. The first symptom was motor deficiency in only 33% of them while in all other cases it was pain. Ambulation capability was the main prognosticator of treatment outcome; 90% of patients who were ambulatory before treatment remained so while 33% of the non-ambulatory patients regained their ability to walk. The grade of motor disturbance was also an important variable: among the non-ambulatory patients, 50% of the paretic but only 14% of the plegic ones became ambulatory. Overall, 51% of the study patients were ambulatory after undergoing radiation. The ambulatory state after treatment was the main predictor for survival.

CONCLUSION

Close cooperation of a multidisciplinary team in diagnosis and treatment according to the above protocol enabled the achievement of good results of radiation treatment in SCC. Early diagnosis and early treatment should further enhance therapeutic outcome.

Palliative subtotal vertebrectomy with anterior and posterior reconstruction via a single posterior approach

OBJECT

Laminectomy for the treatment of spinal metastatic disease is ineffective. Total spondylectomy requiring both anterior and posterior operations may cause undue morbidity in patients with a limited life expectancy. The authors demonstrate the technique, feasibility, and success of subtotal vertebrectomy that is followed by anterior and posterior reconstruction via a simple posterior approach. Although this remains a palliative procedure, it provides circumferential decompression and spinal stabilization by using rigid hardware.

METHODS

The authors present a review of nine of 43 consecutive patients with spinal metastatic disease who underwent operation in a 42-month period. Via a single midline posterior approach, the authors performed single-stage circumferential decompression of the theca followed by anterior and posterior reconstruction. Anterior support is provided by a methylmethacrylate reconstruction retained with Steinmann pins. Posterior reconstruction is achieved by placement of rigid hook or pedicle screw and rod instrumentation. Eight of the nine patients died of progression of underlying disease. All patients remained pain free until days before they died. Except for a patient with paraplegia who did not recover, all other patients remained ambulatory. Despite radio-, chemo-, and steroid therapy, there were no wound infections or breakdowns. One patient underwent reoperation because of a technical error.

CONCLUSIONS

Use of the near-total vertebrectomy followed by anterior and posterior reconstruction from T2 to L3 by using a single midline posterior approach spares the patient, who has a limited life expectancy, the operative risks associated with thoracotomy or thoracoabdominal approaches. The authors restrict the procedure for use in patients with extensive bony disease, noncontiguous spinal involvement, visceral metastases, other contraindications to a transcavitary procedure, and those with advanced age.

Endoscopically assisted decompression for metastatic thoracic neoplasms

STUDY DESIGN

The author describes a technique for complete vertebrectomy and anterior decompression followed by a formal anterior column reconstruction, using readily available endoscopic instruments. This procedure is indicated in patients with radioresistant metastasis of the thoracic spine, particularly those involving the upper thoracic segments where a thoracotomy is difficult and causes a high rate of morbidity. This is also a suitable technique for patients with pulmonary disease who cannot tolerate a standard thoracotomy.

OBJECTIVES

To demonstrate the feasibility and potential benefits of endoscopically controlled decompression through an extrapleural, posterolateral approach.

SUMMARY OF BACKGROUND DATA

Posterolateral decompression of the thoracic spine offers potential advantages in comparison with traditional anterior-posterior procedures combining thoracotomy and posterior instrumentation, including decreased operative time, decreased morbidity, and reduced hospital stay. Results of previous studies have not demonstrated the same benefit for posterolateral decompression as for anterior vertebrectomy and decompression. Drawbacks to the traditional posterolateral decompressions have included poor visualization of the spinal cord and anterior tumor, poor access to tumor on the side contralateral to the approach, and the need to manipulate the spinal cord to completely remove adjacent tumor and tumor adherent to the dura.

METHODS

Surgical indications, rationale, and technique are provided, and initial clinical results are described.

RESULTS

Transpedicular decompression using endoscopy is described in five patients. The mean operative time for the combined procedure was 7.25 hours, with a mean blood loss of 1800 mL. Neurologic recovery and maintenance were excellent. Inpatient days averaged 7.5, and intensive care days averaged 2. One patient died of disease 8 months after surgery, and four were living, with disease, 3-24 months after surgery.

CONCLUSIONS

Endoscopically assisted decompression can reduce morbidity, hospital stay, and treatment costs while matching the efficacy of traditional combined procedures. Endoscopy provides a readily available and easily applied tool that dramatically improves the surgeon's vision, providing light, magnification, and a direct view of remote structures.

Pain due to epidural tumor in cancer patients. Report of two cases and differential diagnosis

The cases of two patients with inguinal pain as the only symptom of a T12 metastatic lesion is reported. The patterns of pain referrals from tumor lesions to the spine, epidural space, and spinal cord are reviewed. Focal back pain and pain reported in a distal distribution can both be associated with epidural or cord disease. The differential diagnosis of back pain in patients with cancer can be difficult but may be crucial in differentiating important neurological complications of systemic neoplasms.

Spinal cord compression in prostate cancer: treatment outcome and prognostic factors

BACKGROUND AND PURPOSE

Spinal cord compression (SCC) is an important complication of metastatic prostate cancer. We have analysed patients treated at the Royal Marsden Hospital to assess treatment outcome and prognostic factors in this patients group.

MATERIALS AND METHODS

We performed retrospective analysis of 69 patients with spinal cord compression and prostate cancer treated at the Royal Marsden Hospital.

RESULTS

At presentation 40 (58%) patients were non-ambulant and 52% were catheterised. Diagnosis was established by myelography in 42% and magnetic resonance imaging (MRI) in 47% of patients. MRI detected significantly more patients with multiple sites of compression (51 versus 7%, P < 0.001). SCC was present at the initial diagnosis of prostatic cancer in 13 patients and 17 patients had received no hormone treatment prior to diagnosis. Following treatment 36 (52%) patients had a functional improvement of motor power with 25/40 (63%) non-ambulant patients becoming ambulant. Seventy-seven percent of patients who had eventual improvement had some improvement in power within 7 days. On multivariate analysis a single level of compression, no previous hormone therapy and a young age (<65 years) predicted for better outcome. When these factors were included an increased radiation dose (>30 Gy) or the addition of surgery did not improve the functional outcome. Following initial recovery; there was a 45% risk of developing a further episode of cord compression at the same or new site by 2 years with a median time to progression of 236 days (range 47-1215 days). The median survival was 115 days (range 5-2016 days) with 25% of patients surviving for 2 years. Patients with no prior hormone therapy had a median survival of 627 days (range 46-1516 days). Other predictors of improved survival on multivariate analysis were a single site of compression and a haemoglobin over 12 g.

CONCLUSIONS

Treatment of SCC in prostate cancer results in improved motor function in the majority of patients. Long-term survival is possible, especially in good performance status patients with no prior hormone treatment. Survivors remain at high risk of subsequent neurological relapse. An early improvement in motor power is a strong predictor of subsequent functional improvement. MRI detects additional sites of asymptomatic SCC which makes it the investigation of choice.

Short-course radiotherapy (8 Gy x 2) in metastatic spinal cord compression: an effective and feasible treatment

PURPOSE

To evaluate the clinical outcome and toxicity of a short-course regimen of radiotherapy (RT) in selected metastatic spinal cord compression (MSCC) patients.

METHODS AND MATERIALS

Between 1993 and 1995, 53 consecutive patients with MSCC from low radio-responsive primary tumors (non small cell lung, kidney, head and neck and gastrointestinal carcinomas, melanoma and sarcomas), or more radio-responsive ones (breast and prostate carcinomas, myeloma and lymphomas) with paresis, plegia, low performance status (PS ECOG > or = 2), and/or short life expectation, underwent short-course RT; a single fraction of 8 Gy repeated after 1 week in responders or stable patients, for a total dose of 16 Gy. Of 49 (92%) evaluable cases, 4 (8%) underwent surgery plus RT and the other 45 RT alone. Medium doses of parenteral dexamethasone (8 mg x 2/d) were given in all cases and precautional anti-emetics to those treated with fields covering the upper abdomen (20 of 49 cases). Median follow up was 25 months (range, 6-34). Response was assessed according to back pain, and motor and bladder capacity before and after RT.

RESULTS

Pain relief was achieved in 67% of patients and motor function response rate reached 63%. Early diagnosis and therapy were very important in predicting response to RT; all but two (91%) pretreatment walking patients and all but one (98%) with good bladder function preserved these capacities. On the contrary, when diagnosis was late, only 38% of nonambulatory patients and 44% of those with bladder retention improved. Median survival was 5 months, with a 30% probability of survival for 1 year. Length of survival was significantly longer for patients able to walk before and/or after RT. Good agreement between survival and duration of response was found with no evidence of relapse in the irradiated spine. Sickness appeared only in a few cases. Slight esophagitis was more frequent: dysphagia for solid foods in one-third of patients irradiated on the thoracic spine. Late toxicity was never recorded.

CONCLUSION

The short-course RT adopted gave a clinical outcome comparable with that resulting from more protracted regimens with only slight side effects. The use of a few large treatment fractions could be explored considering the associated advantages for patients and radiotherapy centers often overloaded by long patient waiting lists.

The efficacy of treatment for malignant epidural spinal cord compression

The aims of this study were to document the efficacy of treatment and to identify factors that were predictive of the outcome in malignant epidural spinal; cord compression. The medical records of patients treated at the Prince Henry and Prince of Wales Hospitals in the period 1980-1989 with a diagnosis of malignant epidural spinal cord compression were reviewed. A total of 94 patients were eligible for the study and were treated by radiotherapy alone (37), surgery alone (19) and surgery followed by radiotherapy (38). Efficacy was determined by measuring complete resolution of symptoms and signs at 1 month after presentation, and also by using an overall functional improvement score (FIS). Complete resolution of individual pre-treatment symptoms that were measured 1 month after treatment occurred as follows: pain (30/88), sensory disturbance (12/61), weakness (8/17), bladder dysfunction (10/42), and bowel dysfunction (10/36). Complete resolution of motor deficit occurred in 7/82 and of sensory deficit in 9/73. The ability to walk was regained in 19/51 previously non-ambulatory patients, and bladder function improved sufficiently to remove an indwelling catheter in 9/32 previously catheterized patients. As judged by FIS, 67 patients improved, 15 patients remained stable and 12 patients deteriorated. Of the treatments given, a combination of surgery followed by radiotherapy was associated with the greatest functional improvement (P = 0.001). The coexistence of 'liver failure' was the only patient-related factor identified which was associated with outcome (P = 0.041). The treatment of malignant spinal cord compression appears to be worthwhile; however, the outcome of treatment is not easy to predict from pretreatment factors. A 'functional improvement score' may be useful in assessing treatment efficacy.

Radiologic features compared to clinical findings in a prospective study of 153 patients with metastatic spinal cord compression treated by radiotherapy

Plain radiography, myelography and post-myelographic CT-scan are described and related to clinical findings in a prospective study of 153 consecutive patients with myelographic signs of spinal cord compression. The majority of the metastatic tumours arise in the vertebral body or the pedicles. In 80% of the patients with total blockage to the contrast medium on myelography the post-myelographic-CT showed passage of the contrast medium. Ambulatory function at time of diagnosis was correlated to the degree and the localization of the epidural block. In 64 patients who underwent a second myelography, the post-treatment findings of sensory function were correlated to radiological regression.

Indications and results of combined anterior-posterior approaches for spine tumor surgery

Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5-year period (1989-1993) at a single institution. Major primary sites of tumor included breast (14 cases), chordoma (14 cases), lung (12 cases), kidney (11 cases), sarcoma (13 cases), plasmacytoma (10 cases), and others (36 cases). Prior to surgery, 55 patients (50%) had received prior treatment. Forty-eight patients (44%) were nonambulatory, and severe paraparesis was present in 20 patients. Fifty-three patients (48%) underwent combined anterior-posterior resection and instrumentation. 33 (30%) underwent anterior resection with instrumentation, 18 (16%) underwent anterior or posterior resection alone, and the remaining six patients (5%) underwent posterior resection and instrumentation. Major indications for anterior-posterior resection included three-column involvement, high-grade instability, involvement of contiguous vertebral bodies, and solitary metastases. Postoperatively, 90 patients improved neurologically. The overall median survival was 16 months, with 46% of patients surviving 2 years. Fifty-three patients (48%) suffered postoperative complications. Despite the high incidence of complications, the majority of patients reported improvement in their quality of life at follow-up review. Our findings suggest that half of all patients with spinal malignancies require combined anterior-posterior surgery for adequate tumor removal and stabilization.

Indications and results of combined anterior-posterior approaches for spine tumor surgery

Spinal instrumentation currently allows gross-total resection and reconstruction in cases of malignancies at all levels of the spine. The authors analyzed the results in 110 patients who underwent surgery for primary and metastatic spinal tumors over a 5 year period (1989–1993) at a single institution. Major primary sites of tumor included breast (14 cases), chordoma (14 cases), lung (12 cases), kidney (11 cases), sarcoma (13 cases), plasmacytoma (10 cases), and others (36 cases). Prior to surgery, 55 patients (50%) had received prior treatment. Forty eight patients (44%) were nonambulatory, and severe paraparesis was present in 20 patients. Fifty three patients (48%) underwent combined anterior-posterior resection and instrumentation, 33 (30%) underwent anterior resection with instrumentation, 18 (16%) underwent anterior or posterior resection alone, and the remaining six patients (5%) underwent posterior resection and instrumentation. Major indications for anterior-posterior resection included three-column involvement, high-grade instability, involvement of contiguous vertebral bodies, and solitary metastases. Postoperatively, 90 patients improved neurologically. The overall median survival was 16 months, with 46% of patients surviving 2 years. Fifty-three patients (48%) suffered postoperative complications. Despite the high incidence of complications, the majority of patients reported improvement in their quality of life at follow-up review. Our findings suggest that half of all patients with spinal malignancies require combined anterior-posterior surgery for adequate tumor removal and stabilization.

Central nervous system metastasis in breast cancer

BACKGROUND AND PURPOSE

Central nervous system (CNS) metastasis occurs in at least 30% of patients with breast cancer. Standard treatment is the same as in other solid tumors, though clinical behavior, and sensitivity to radiation therapy (RT) and to chemotherapy may differ considerably. Most of these patients die within a few months, but a substantial subgroup may survive a year or more. The last decade has given rise to new diagnostic methods, new surgical and radiotherapeutic techniques, and the clinical evidence of a chemotherapy permissive blood-brain barrier in CNS metastases. The literature was reviewed to assess the clinical impact of early diagnosis, recognition of prognostic factors, and of the recently developed therapeutic approaches.

MATERIAL AND METHODS

Review of the literature on CNS involvement in breast cancer focusing on clinical studies on early diagnosis, new modes of treatment, and factors influencing outcome.

RESULTS

Although randomized studies are still awaited, systemic chemotherapy seems a valuable alternative for RT of brain metastases in selected cases. In meningeal carcinomatosis, long survival may be independent of intraventricular chemotherapy. Neurotoxicity of intensive intraventricular treatment is considerable. In epidural metastasis, early diagnosis with prompt start of treatment remains the crucial factor for outcome. Radiation therapy is the mainstay of treatment of epidural metastasis, but new surgical techniques and even systemic chemotherapy should be considered in selected cases.

CONCLUSIONS

Recognition of prognostic factors combined with appropriate use of various recently developed therapeutic possibilities will improve the clinical outcome including better local tumor control and less treatment-induced neurotoxicity in a considerable number of patients with CNS metastasis from breast cancer.

Thoracic spine fractures in patients older than 50 years

The charts and radiographs of 70 patients older than 50 years of age with thoracic vertebral body collapse were reviewed retrospectively. Fifteen patients had traumatic fractures and 34 had osteoporotic collapse of thoracic vertebrae. Metastasis was the underlying disease process in 18 patients and multiple myeloma in the remaining 3 patients. Thirteen patients had fractures involving the upper half of the dorsal spine, of which 8 (61.5%) were metastatic, 4 (30.8%) osteoporotic, and 1 (7.7%) traumatic. All patients with osteoporotic fractures of the upper dorsal spine also had 1 or more fractures of the lower dorsal or lumbar spine. There were 11 metastatic, 80 osteoporotic, 14 traumatic, and 3 fractures secondary to multiple myeloma involving the lower dorsal spine. There were no infections or primary bone tumors. The difference in the frequency of metastatic fractures against other etiologies involving the upper versus the lower thoracic spine was highly statistically significant.

Cadaveric vascular anatomy for total en bloc spondylectomy in malignant vertebral tumors

STUDY DESIGN

The authors studied the vascular anatomy of the thoracic and lumbar spine in cadavers related to the clinical use of total en bloc spondylectomy in malignant vertebral tumors.

OBJECTIVE

To enhance anatomic knowledge on major and associated segmental vessels surrounding the anterior vertebral column of the thoracic and lumbar spine.

SUMMARY OF BACKGROUND DATA

No reports have, to the authors' knowledge, referred clinically to the anatomic relationship between the vascular system and the anterior vertebral column in performing posterior total en bloc spondylectomy on the thoracic and lumbar spine.

METHODS

The authors studied the major vessels, segmental arteries and veins, and tendinous portions of the lumbar diaphragm inserting onto the vertebrae in 21 cadavers to view the vascular system surrounding the anterior vertebral column in the thoracic and lumbar spine.

RESULTS

The aorta descended in direct contact with the anterior vertebral column below T4 or T5 and branched into two common iliac arteries at L3 in one cadaver, at L3-L4 in two, at L4 in eight, at L4-L5 in nine, and at L5 in one. The uppermost intercostal artery originated at T4 or T5, and 48 (14%) variations in 348 intercostal arteries did not originate from the thoracic aorta. Two common iliac veins became confluent at L3-L4 in one subject, at L4-L5 in 13, and at L5 in seven. The inferior vena cava ascended in tight contact with the vertebral column and entered into the vena caval foramen of the diaphragm anterior to the right medial crus. The right medial crus of the diaphragm originated from the vertebra at L1-L2 in one subject, at L2 in two, at L2-L3 in 14, and at L3-L4 in four, whereas, on the left, this ligamentous origin located at L1-L2 in six, at L2 in two, at L2-L3 in 11, and at L3-L4 in two. The first two lumbar arteries ran consistently in the space between the medial crus and the vertebral column.

CONCLUSIONS

Total en bloc spondylectomy conducted posteriorly is less likely to damage the thoracic aorta from T1 to T4 but, distal to T5, the aorta must be carefully retracted anteriorly before manipulation of the affected vertebra(e). For a malignant tumor involving L1 or L2, the medial and, occasionally, the intermediate crura of the diaphragm and the first two lumbar arteries must be treated carefully before spondylectomy. Malignant tumors involving the L3 and L4 vertebral bodies can be approached with a total en bloc spondylectomy technique only when the inferior vena cava has been safely retracted anteriorly.

Outcome after limited posterior surgery for thoracic and lumbar spine metastases

The efficacy of 'limited posterior surgery' for metastases in the thoracic and lumbar spine was studied prospectively in 51 patients (32 men and 19 women, mean age 64 years). The most common primary tumors were prostate, breast, and renal carcinoma, 37 patients had metastases in the thoracic spine and 14 in the lumbar spine. Indications for surgery were severe pain or neurologic deficit. Of the 46 patients with neurologic symptoms, 25 were unable to walk. Surgery was confined to direct or indirect decompression and stabilization with a pedicle screw fixator over few segments as possible. Pain, as well as a variety of functional performance parameters and residential status were registered preoperatively and after surgery at 3, 6, 9, and 12 months, and at 6-monthly intervals thereafter. Pain was rated by the patient on a Visual Analog Scale, and functional performance was assessed with the Eastern Co-operative Oncology Group (ECOG) Performance Status Scale. We had no perioperative neurologic deterioration or death. Nineteen of the 25 nonambulatory patients regained their walking ability. Postoperative pain relief was significant and lasting over time. Nearly half of the patients attained improvement in functional performance. The median survival was 8 months. Older age and intact postoperative walking ability were positive factors for survival.

Skeletal metastases

This synthesis of the literature on radiotherapy for skeletal metastases is based on 171 scientific articles, including 13 randomized studies, 24 prospective studies, and 79 retrospective studies. These studies involve 13054 patients. Radiotherapy has been well documented as a method for alleviating pain, but the mechanisms underlying this effect are largely unknown. When used for pain palliation, radiotherapy achieves freedom from pain, or substantial alleviation of pain in nearly all cases, with few side effects. Half-body irradiation is effective in treating multiple metastatic sites and should be considered for use more frequently. However, this increases the requirements on equipment, dosimetry, and hospital beds. Systemic radiotherapy with radionuclides may be indicated for generalized skeletal pain. The role of radiotherapy in preventing or healing fractures is not fully evaluated. Optimum dose levels and fractionation schedules have not been established. Early radiotherapy for spinal cord compression may prevent symptoms from worsening, but the effects on existing paralysis are modest.

Effectiveness of radiation therapy without surgery in metastatic spinal cord compression: final results from a prospective trial

PURPOSE

In assessing effectiveness of radiation therapy (RT) in metastatic spinal cord compression (MSCC), we performed a prospective trial in which patients with this complication were generally treated with RT plus steroids, and surgery was reserved for selected cases.

METHODS AND MATERIALS

Two hundred seventy-five consecutive patients with MSCC entered this protocol. Twenty (7%) underwent surgery plus RT, another 255 received RT alone. Of all eligible patients, 25 (10%) early deaths and 21 (8%) entering a feasibility study of RT without steroids, were not evaluable. Of the 209 evaluable cases, 110 were females and 99 males, and median age was 62 years. Median follow-up was 49 months (range, 13 to 88) and treatment consisted of 30 Gy RT (using two different schedules) together with steroids (standard or high doses, depending on motor deficit severity). Response was assessed according to back pain and motor and bladder function before and after therapy.

RESULTS

Back pain total response rate was 82% (complete or partial response or stable pain, 54, 17, or 11%, respectively). About three-fourths of the patients (76%) achieved full recovery or preservation of walking ability and 44% with sphincter dysfunction improved. Early diagnosis was the most important response predictor so that a large majority of patients able to walk and with good bladder function maintained these capacities. When diagnosis was late, tumors with favorable histologies (i.e., myeloma, breast, and prostate carcinomas) above all responded to RT. Duration of response was also influenced by histology. Favorable histologies are associated to higher median response (myeloma, breast, and prostate carcinomas, 16, 12, and 10 months, respectively). Median survival time was 6 months, with a 28% probability of survival for 1 year. Survival time was longer for patients able to walk before and/or after RT, those with favourable histologies, and females. There was agreement between patient survival and duration of response, systemic relapse of disease being generally the cause of death.

CONCLUSION

Early diagnosis of MSCC was a powerful predictor of outcome. Primary tumor histology had weight only when patients were nonwalking, paraplegic, or had bladder dysfunction. The effectiveness of RT plus steroids in MSCC emerged in our trial. The most important factors positively conditioning our results were: the high rate of early diagnoses (52%) and the number of tumors with favorable histologies (124 out of 209, 63%) recruited, and the choice of best treatment based on appropriate patient selection for surgery and RT or RT alone.

Surgical management of vertebral neoplasia: who, when, how and why?

To determine the role of surgery in vertebral neoplasia, we conducted a retrospective review of patients undergoing surgery for vertebral neoplasia in the Royal Orthopaedic Hospital, Birmingham, and Coventry and Warwickshire Hospital, Coventry. Surgery included decompression, stabilisation or both. The neurological status was assessed by Frankel grading before and after surgery. Of 70 patients undergoing surgery, 14 were neurologically intact preoperatively, and a further 25 were weak but ambulatory. Following surgery, 35 were intact, and a further 22 were ambulatory. Sixty-six patients (94%) obtained good pain relief. Survival correlated with histology and younger age at presentation, but not with level, neurology at presentation or type of surgery. We conclude that neurological status, pain relief and mechanical stability are better after appropriate surgery than after radiotherapy or inappropriate surgery. Failure to consider the surgical option may deny the chance of significant neurological recovery.

Surgery of cervical spine metastases: a retrospective study

Fifty-one consecutive patients with metastatic lesions of the cervical spine were treated surgically. The most common primary tumor types were breast cancer and myeloma. In 14 (27%) patients, the cervical lesion was the first manifestation of the malignancy. All patients suffered from severe pain but only six had long tract symptoms. Five tetraparetic patients were confined to bed. Vertebral body collapse occurred in 73% of cases. The surgical technique was individualized according to the patient's general condition, the site of metastasis on the vertebra, and the level and number of levels bearing in mind that the treatment is palliative in nature. The goal of treatment was a better quality of life. In the upper cervical spine the technique described by Sjöström et al. was used, if technically possible. If the odontoid process had been totally destroyed, an occipitocervical stabilization was chosen. In the lower cervical spine, an anterior approach was used to resect the tumor growth. Anterior support was provided with bone cement if the patient was not expected to survive long; otherwise bone grafting was used. In cases with two or more levels of involvement, a combined anteroposterior stabilization was usually performed. Good pain relief was achieved postoperatively. The operation was generally well-tolerated by the patients, mild dysphagia being the most common complaint. One patient died 2 days postoperatively of heart failure, giving a postoperative mortality of 2%. Rhizopathy symptoms were relieved totally in 15 patients and partially in 6.(ABSTRACT TRUNCATED AT 250 WORDS)

Metastatic epidural spinal cord compression: current concepts and treatment

Metastatic epidural spinal cord compression (MESCC) is a medical emergency complicating the course of 5-10% of patients with cancer [1]. When diagnosis and treatment is early with the patient ambulatory prognosis for continued ambulation is good [2]. If the patient is nonambulatory or paraplegic, prognosis for meaningful recovery of motor and bladder function is markedly decreased. In the last decade, significant advances in the understanding, management and treatment of metastatic epidural spinal cord compression have occurred. Recent pathophysiological and pharmacological animals studies have afforded insights into disease mechanisms [3-9]. The audit of standard methods of investigation and magnetic resonance imaging have resulted in revision of guidelines for patient evaluation [10-17]. Finally, new surgical philosophies and technical advances have generated interest and controversy [18-25]. With improved clinical awareness, new imaging modalities will help us diagnose epidural spinal cord compression earlier and institute appropriate treatment.

The management of metastatic spinal cord compression: a radiotherapeutic success ceiling

PURPOSE

In assessing the effectiveness of the management of metastatic spinal cord or cauda equina compression, we performed a retrospective analysis of 70 patients with this complication whom we treated from 1985 to 1989.

METHODS AND MATERIALS

The most frequent primary diagnoses in our series were carcinomas of unknown origin and of the breast, lymphoproliferative disease, lung cancer, and prostatic carcinoma. We used the Findlay classification to group all patients according to their pre-therapeutic functional motor status as Grade I (24 patients or 34%), Grade II (27, or 39%) or Grade III (19 or 27%). Treatment consisted of 30-45 Gy of irradiation (using two different schedules) together with high-dose dexamethasone; in only five cases was there surgical intervention.

RESULTS

We found that a powerful predictor of response to radiotherapy was the patient's neurologic status (Findlay grade) at the time of diagnosis: 66% of previously ambulatory patients remained so, whereas 30% of non-ambulatory patients and only 16% of paraplegic patients regained the ability to walk. Another important predictor of response was primary tumor histology, with the most favorable responses to radiation therapy having been observed in lymphoproliferative diseases and in breast cancer, but with some response in other radiosensitive malignancies as well.

CONCLUSION

The similarity of our results to those of other centers leads us to conclude that a radiotherapeutic success ceiling of 80% may have been reached for Findlay Grade I patients with metastatic spinal cord compression. In view of this, we suggest that future therapeutic endeavour would be best directed toward early diagnosis of the condition.

Malignant spinal cord compression: a prospective evaluation

PURPOSE

To determine the influence of treatment on ambulancy, pain control and functional outcome of patients with Malignant Spinal Cord Compression.

METHODS AND MATERIALS

One hundred and thirty-seven patients with Malignant Spinal Cord Compression presenting or referred to the Department of Radiation Oncology, Westmead Hospital between August 1, 1989 and August 1, 1990 were studied prospectively. Patients were treated with palliative radiation therapy alone, surgery followed by radiotherapy or surgery alone. Two patients were not treated. Post-treatment outcome was assessed in terms of ambulatory status, improvement in pain and functional independence using the Functional Independence Measure.

RESULTS

Thirteen of 16 patients (81%) who were ambulant pre-treatment remained ambulant after treatment. Two of 16 patients (16.5%) who were non-ambulant pre-treatment became ambulant following treatment. Pain improved following treatment in 22 of 30 patients (73%). This benefit was seen equally for ambulant and non-ambulant patients. A high level of functional independence was maintained in patients who remained ambulant.

CONCLUSION

We conclude that prompt treatment of patients with Malignant Spinal Cord Compression while still able to walk is effective in maintaining ambulancy and functional independence, and that treatment improves pain in most patients.

Biomechanical effects of laminectomy on thoracic spine stability

Thoracic columns (T1-L1 levels) from 15 fresh human cadavers were used to quantify alterations in the biomechanical response after laminectomy. Eight specimens were tested intact (Group I); the remaining seven preparations were tested after two-level laminectomy (Group II) at the midheight of the column. All specimens were fixed at the proximal and distal ends and loaded until failure. Force and deformation were collected by use of a data acquisition system. Failure of the Group I specimens included compressive fractures with or without posterior element distractions, generally at the midheight of the column. Group II preparations failed at the superior aspect of laminectomy or at a level above laminectomy, suggesting an increased load sharing. Biomechanical responses of the Group II preparations were significantly different (P < 0.05) from those of the Group I specimens at deformations from the physiological to the failure range. In addition, failure forces for Group II preparations were significantly lower (P < 0.001) than for Group I specimens. The stiffness and energy-absorbing capacities of the laminectomized specimens were also significantly different (P < 0.05) from those of the intact columns. In contrast, the deflections at failure for the two groups were not statistically different, suggesting that the human thoracic spine is deformation sensitive. Our data demonstrate that a two-level laminectomy decreases the strength and stability of the thoracic spine throughout the loading range. Although this is not a practical concern with an otherwise intact vertebral column, laminectomy, when other abnormalities such as vertebral fracture, tumor, or infection exist, may require stabilization by fusion and instrumentation.