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Surgical treatment of lumbar spinal stenosis in patients aged 65 years and older
of Gerontology and Geriatrics 35 (2002) 143–152 www.elsevier.com/locate/archger
Surgical treatment of lumbar spinal stenosis in patients aged 65 years and older S. Shabat a,*, Y. Leitner a, M. Nyska a, Y. Berner b, B. Fredman c, R. Gepstein a a Spine Unit, Orthopaedic Surgery Department, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel b Department of Geriatrics, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel c Department of Anesthesiology, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel
Received 18 July 2001; received in revised form 10 January 2002; accepted 11 January 2002
Abstract Spinal stenosis syndrome affects mainly patients at their 5th– 6th decades of life. The main goals of surgical treatment in the elderly are to allow the individual to walk longer distances, maintain the activities of daily living (ADL) and social life. Our aim was to evaluate the results of surgical treatment for lumbar spinal stenosis in elderly patients. All patients over 65 years of age who underwent surgery due to spinal stenosis syndrome between 1990 and 1998 were evaluated. There were 29 males and 17 females aged between 65 and 90 years. The clinical presentation included low back pain (89%), intermittent claudication (100%) and neurological involvement (87%). The radiological examination showed a frequent narrowing at the level L4–L5 in 93.5% of the patients. The results of the surgery in a mean follow-up of 22 months were good to excellent in 80% of the patients, fair in 11%, and poor in 9%. An improvement in the intensity of pain and in walking distances was noted in 89 and 85% of the patients, respectively. Improvement was achieved in the level of daily activity and in social lives in 57 and 61%, respectively. Major and minor complication rates were 6.5 and 19.5%, respectively. No mortality was noted in this series. Eighty-seven percent of the patients were satisfied with the results of the surgery. We conclude that Surgery for spinal stenosis is a successful and relatively safe procedure, also for patients aged over 65, and should be considered as a treatment option for these patients. © 2002 Elsevier Science Ireland Ltd. All rights reserved. * Corresponding author. Tel.: + 972-9-7472549; fax: +972-9-7423230. E-mail address: [email protected] (S. Shabat). 0167-4943/02/$ - see front matter © 2002 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 7 - 4 9 4 3 ( 0 2 ) 0 0 0 1 6 - X
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Keywords: Spinal stenosis; Elderly; Surgery; Rehabilitation
1. Introduction A lumbar spinal stenosis syndrome results from narrowing of the spinal canal, nerve root canal, or the intervertebral foramen leading to compression of the spinal cord or the nerve roots (Onel et al., 1993; Johnsson, 1995). The clinical syndrome presents in the 5th– 6th decades and includes: low back pain, intermittent claudication, morning stiffness, and neurological involvement. The neurological symptoms include muscular weakness, paresthesia, hypo-aesthesia, hypo-reflexia, and rarely incontinence. The pathophysiology of this syndrome is a degenerative process of the facets (Onel et al., 1993; Johnsson, 1995). The diagnosis is established by computerized tomography (CT) and magnetic resonance imaging (MRI) (Maravilla et al., 1985; Schonstrom et al., 1985). The conservative treatment includes bed-rest, analgesics, non-steroidal anti-inflammatory drugs, physiotherapy, ultrasound, and epidural facet blocks (Spengler, 1987; Onel et al., 1993; Atlas et al., 1996). Nevertheless, the treatment of choice in cases with severe stenosis is decompressive laminectomy, known to have good results and a low rate of complications (Verbiest, 1977). The syndrome in the elderly might increase morbidity and mortality due to side effects of the conservative treatment, reduced activity or sequella of recumbancy. Surgical treatment might prevent these sequella and improve the quality of life even in the elderly (Bridwell, 1994). In the elderly group of patients, the clinical symptoms can be more pronounced, and the surgical treatment is often more complicated (Ciol et al., 1996). This work is a retrospective case study aimed to evaluate the results of the surgical treatment in elderly patients over 65 years of age and the factors that may affect these results.
2. Patients and methods All patients over the age of 65 years, who were operated for lumbar spinal stenosis during the years 1990– 1998 in our medical center, were enrolled in this study. Each patient underwent evaluation that included history taking, physical examination, plain X-ray films, CT scan and/or MRI of the lumbar spine. Twentytwo patients suffered from background diseases, which included mild congestive heart failure (n= 4), arrhythmia (n = 3), hypertension (n =9), non-insulin dependent diabetes mellitus (n =2), mild chronic obstructive pulmonary disease (n= 2), mild chronic renal failure (n= 3) and peripheral vascular disease (PVD) (n= 5). Twelve patients used to smoke regularly before the operation. Nineteen patients out of the 22 used to take drugs to control their background disease. All patients underwent decompressive laminectomy. Foraminotomy or facetectomy were added
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according to the surgeon’s decision at operation. In some of the patients, a discectomy was needed as well. One patient needed a fusion procedure. Twenty-five patients were discharged at the day of operation or 1 day afterwards. Ten and four patients were discharged 2 and 3 days after the operation, respectively, and the remaining seven patients were discharged 4 days or more after the operation. All patients were followed post-operatively and underwent repeated physical examinations, for pain, function and neurological damage. The follow-up periods varied from 2 to 76 months after the operation (mean, 22 months). We used the Oswestry index category for evaluating the following parameters before and after operation (Fairbank et al., 1980). (A) intensity of pain was used by the visual analogue scale (VAS) score (Joyce et al., 1975); (B) the use of analgesics (absence of analgesics, use of analgesics with a total relief, use of analgesics with partial relief, use of analgesics without any relief); (C) maximal walking distance (walking any distance, walking up to 1 km, walking up to 500 m, walking only few meters or using a cane or a walker); (D) the need of help with activities of daily living (ADL) (individual is capable of taking care of himself, need of only little help with ADL, need of a daily-basis help in most of ADL, individual is not capable of clothing, bathing, etc. without being helped); (E) participation in social life (maximal social life as defined by the patient, only a slight reduction in social life in comparison with a maximum definition, limited social life, not having any social life). The neurological impairment was measured (according to history and physical examination), which included straight leg raising (SLR) tests and motor, sensory, reflex and continence. This was noted before and after the operation, and whether there was improvement (full or partial), unchanged condition, or even deterioration. Motor examination was measured on a scale of 0–5 (0, no evidence of contractility; 1, evidence of slight contractility, but no joint motion, 2, complete range of motion with gravity eliminated; 3, complete range of motion against gravity; 4, complete range of motion against gravity with some resistance; 5, complete range of motion against gravity with full resistance). Sensory examination was performed according to the sensation in the affected area before and after the operation, and whether it was fully recovered to full sensation, partially recovered, not changed or deteriorated. Complications after surgery were assessed as well (infection (deep or superficial), any permanent residual neurological damage, dural tear, other complications and death). In addition all patients were asked about their satisfaction from the operation and their willingness to undergo the operation if they had known in advance the operative results.
2.1. Statistical analysis Statistical analysis was done by the SPSS data processing program. In order to compare differences among the various groups of patients, the Student’s t-test was performed for independent variables at two levels. For three or more levels the one-way analysis of variance test followed by a Scheffe post hoc test was performed. In the case of variables that were analyzed from scales that may not result in equal interval data, the Pearson correlation coefficient test was employed.
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3. Results Forty-six patients more than 65 years of age were operated due to lumbar spinal stenosis in our institution between 1990 and 1998. These patients comprise this study. The age of the patients at time of operation ranged between 65 and 90 years (median 72 years). Sixteen patients were between 65 and 69 years old (35%), 17 patients were between 70 and 74 years of age (37%), and the remaining 13 patients were more than 75 years old (28%). Seventeen out of the 46 patients (37%) were females, and 29 patients (63%) were males. Major background diseases included PVD which was noted in five of the patients, non-insulin diabetes mellitus in two patients, and 12 patients used to smoke regularly before the operation. The clinical symptoms and signs of the spinal stenosis among the patients are summarized in Table 1. These symptoms affected the patients between 5 days and 40 years prior to operation (median, 36 months). All patients underwent CT and/or MRI imaging evaluation for the spinal stenosis. Forty-three patients (94%) had spinal stenosis at the L4– L5 level, followed by 21 patients (46%) at L3– L4 level, 13 patients (29%) had spinal stenosis at L5– S1 Level, ten patients (22%) at L2– L3 level and two patients (4%) at L1– L2 level. The number of segments involved varied from 1 to 4. Seventeen patients had one level and 17 patients had two levels of segmental involvement. Three segmental involvement was noted in ten of the patients and only two patients had four segmental involvement. The number of the involved segments was not influenced by the age of the patients, nor was it correlated with the intensity of the clinical symptoms (P\0.05). In a multi-segmental stenosis, there was a higher tendency of neurological impairment but this was not statistically significant. Table 1 The clinical symptoms and signs of the spinal stenosis Clinical symptoms and signs
Number of patients
Low back pain Intermittent claudication Neurological impairment Motor impairment alone Sensory impairment alone Reduction in reflexes (general) Decrease ankle reflex alone Decrease patellar reflex Urine incontinency Anal incontinency Intact SLR examination Positive SLR test (unilateral) Positive SLR test (bilateral)
41 46 40 18 33 28 27 14 1 1 29 5 12
(89%) (100%) (87%) (39%) (72%) (61%) (59%) (31%) (2.2%) (2.2%) (63%) (11%) (26%)
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Table 2 The change in motor and sensory examination in patients with respective deficits prior to operation Change
Motor examination
Sensory examination
Full improvement (5/5) Partial improvement No change Reduction Total
10 (55%) 3 (17%) 3 (17%) 2(11%) 18 (100%)
19 6 6 2 33
(58%) (18%) (18%) (6%) (100%)
Thirty-one patients (67%) underwent decompressive laminectomy alone. Fourteen additional patients (30%) had discectomy in addition to the decompressive laminectomy, and one patient (2%) had a combination of decompressive laminectomy, and one patient (2%) had a combination of decompressive laminectomy and fusion. Twenty nine (63%) and eight (17%) of the patients had estimated intensity of pain of ten and nine, respectively, prior to the operation. The average VAS score before the operation was 8.64 and was reduced to 3.34 post operatively (PB 0.0001). Forty-one patients had improvement in their subjective pain, while one patient had no change and four patients had increased pain post-operatively. No correlation was found between smoking and degree of pain or pain improvement by the operation. Patients with PVD suffered more from pain pre-operatively (PB 0.05). In addition they had less improvement in terms of subjective pain than the other patients (P B 0.05). Patients who had multi-level stenosis had more improvement in pain after the operation (P B0.05). The vast majority of patients used analgesics prior to operation, and most of them reported no pain relief; while after the operation most of the patients (41 out of 46 patients) did not need to use analgesics. The operation improved the walking distance capacity (PB 0.05). Thirty-nine patients (85%) had improvement in walking distance due to the operation. Three patients (6%) could ambulate to the same distance, and four patients (9%) had reduction in walking distance after the operation. No relation was found between diabetes or PVD to the improvement in walking distance. Twenty-six patients (57%) had improvement in ADL performance, 18 patients (39%) had the same ADL performance before and after the operation, and two patients (4%) had reduction in ADL performance (PB 0.01). Social life performance was also improved significantly after the operation (PB 0.01). Prior to the operation, 64% of the patients had restriction in their social life activities, while after the operation only 17% of the patients were restricted in any means in their social life. The change in motor and sensory examination in patients with respective deficits prior to the operation is summarized in Table 2. Three patients with intact muscle strength before the operation developed partial muscle weakness (4/5) after the operation. No relation was found between the elapsed time until the operation to the motor improvement. Three patients (6.5%)
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with intact sensory examination developed partial sensory deficits after the operation as well. Two patients who were incontinent prior to operation returned to full continence after the procedure. In 38 patients the straight leg-raising (SLR) test was normal after the operation. Among these patients, 95% showed improvement of SLR, and 5% showed no change in the SLR test. In the remaining eight patients with positive SLR test after the operation, 37.5% showed improvement, and 25 and 37.5% showed no change and exacerbation, respectively, in this test in relation to the examination prior to operation. In the last group of eight patients with pathological SLR test that was noted after the procedure the overall result of the operation was poorer than those with normal SLR. Four patients had normal SLR before the operation, which became positive after it. None of these patients showed improvement due to the operation. Nine minor operative complications were recorded (19.5%) and included superficial wound infection, atalectasis, urinary tract infection, residual neurological damage and dural tear. Major operative complications were noted in three patients (6.5%) and included pulmonary emboli, myocardial infarction and permanent neurologic injury. Complications are summarized in Table 3. The patients who had dural tear did not have neurological signs. Patients who were operated for one segment had fewer complications than patients who were operated for multi-segment stenosis (P B 0.05). No correlation was found between the background diseases (diabetes, smoking and PVD) and the complication rate. Fourteen (30%) and 23 (50%) of the patients showed excellent and good results, respectively; five (11%) and four (9%) patients had fair and poor results, respectively, following the operation. The satisfaction scale rate of the patients after the operation is summarized in Table 4. No differences were found between the different age groups and sex of the patients and their satisfaction with the outcome. Patients over age 75 years old showed the same results as the other age groups.
Table 3 Minor and major complications Minor complication
Number of patients
Major complications
Number of patients
Superficial wound infection Atalectasis Urinary tract infection
2 (4.3%) 1 (2.2%) 2 (4.3%)
Pulmonary embolism Myocardial infarction Permanent neurologic damage
1 (2.2%) 1 (2.2%) 1 (2.2%)
Residual neurologic damage Dural tear Total
2 (4.3%) 2 (4.3%) 9 (19.5%)
Total
3 (6.5%)
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Table 4 Satisfaction scale rate of the patients after the operation Satisfaction
Number of patients
Very satisfied Pretty satisfied Not so satisfied Unsatisfied Total
25 15 3 3 46
(54%) (33%) (6.5%) (6.5%) (100%)
4. Discussion This survey comprises 46 elderly patients (more than 65 years old) who underwent operation due to spinal stenosis. Spinal stenosis is considered to be increased as a cause for low-back and lower-extremity pain, especially in the elderly group of patients. Today, spinal stenosis is the leading diagnosis among elderly patients who undergo spine operation (Turner et al., 1992). However, the usual symptoms of spinal stenosis are often considered either by the primary care physician or by the elderly patient himself, as part of the natural process of aging, which one should live with, for the rest of his life. The primary care physician often tend not to send the elderly patient to a spine specialist, or to offer him operation because of the fear from complications and mortality. Some reports have documented that the success rate of these operations in this group of patients is the same as for young patients, and with minimal mortality (Johnsson et al., 1992; Turner et al., 1992). Even in octogenarians good results were reported for 85% of the cases with low morbidity (Bridwell, 1994). Failed conservative treatment without operative option in the elderly group of patients can eventually lead to reduced activity, immobility with its consequences and eventually reduced quality of life. Least invasive surgical procedure can obtain the best results if the correct diagnosis is made, and if the operation is carried out within the first years of the disease (Niggemeyer et al., 1997). This conclusion is of great benefit to elderly, who may have a higher complication rate. However, in the elderly, early diagnosis of spinal stenosis is more difficult to establish, because of the bewildering medical problems and multiple symptoms noted in physical and mental polymorbidity of old age. The clinical symptoms in our group of patients were similar to the symptoms reported in the literature. The vast majority of the patients suffered from low back pain. This is considered to be the first noticeable symptom (Jonsson and Stromqvist, 1993). Neurogenic claudication is usually expressed by pain radiating to the buttocks, thigh, leg or sometimes the foot, exacerbated by physical activities such as walking mainly downhill (Jonsson and Stromqvist, 1993). The pain is exacerbated by physical activity usually while walking a distance. In our series all patients suffered from neurogenic claudication. It is important to distinguish the neurogenic claudication from vascular claudication. In the latter, the pain stops immediately when resting, and in spinal stenosis the pain is relieved while perform-
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ing flexion of the lumbar spine (Jonsson and Stromqvist, 1993). Some authors advocate performing Doppler studies before deciding that the cause of the claudication is spinal rather than vascular (Bridwell, 1994). We did not perform these studies on a routine basis. A peripheral vascular cause of the leg pain was investigated only in patients with diminished pulses and reduced temperature and turgor of the lower extremities. Some of the patients in this series suffered from neurological deficits, mainly sensory and reduced ankle jerk, and to a lesser extent motor deficit. Since the stenosis develops gradually over the years, there is time for accommodation of the neural tissue, and thus even a severe stenosis can cause only mild neurologic sequela (Spengler, 1987). About two thirds of our patients (29 out of 46 Table 1) had intact SLR test. This test is usually positive in about 50% of the young patients (Turner et al., 1992; Jonsson and Stromqvist, 1993; Onel et al., 1993). However, in the elderly group of patients, it is unusual for them to have any nerve root tension signs presented as negative SLR, as are seen in younger patients with lumbar disc herniations (Bridwell, 1994). Only few patients in this series had incontinence, which is in correlation to a severe long-standing stenosis. No relation was found between the background disease such as diabetes, PVD, or smoking to the neurologic damage. This is supported by Cinnoti et al., who examined the relation between lumbar spinal stenosis and diabetes (Cinotti et al., 1993). The fact that no deterioration was found in this sub-group of patients can be explained by the small number of patients in our series who suffered from these background conditions. Multi-level stenosis, often bilateral, is the common presenting feature. The L4 –L5 and L3 –L4 segments are the most common involved. The least frequent are L5 –S1 and T12–L1 (Spengler, 1987; Bridwell, 1994). In this study the most common involved segments were L4– L5 and L3 – L4 as reported in the literature. However, the L5– S1 segment was the third to be involved in frequency, and that is contrary to the assumption that it is stabilized by the iliotransverse ligament. This series represents only the operated patients and not all patients with spinal stenosis. Another explanation is that in the elderly patients the ilioinguinal ligament is relatively weakened and can cause instability leading to stenosis of this level. The mainstay of surgical treatment is the appropriate posterior decompression. Some patients with deformities may also require posterior fusion and posterior instrumentation (Bridwell, 1994). Out of the 46 patients presented here only one underwent fusion. Even though a higher rate of re-narrowing is noted if a fusion is not performed, the rehabilitation without a fusion is much shorter, and the patient may be back to his or her previous activity level by 2 months postoperatively, in comparison to a closer to a year if fusion and instrumentation are used (Bridwell, 1994). The complication rate was found to be higher in a large metaanalysis performed on studies which were done over a 20 year period (Niggemeyer et al., 1997). Since in this series we deal with elderly patients, and theirreturn to normal life should be as fast as possible, we do not advocate liberal use of posterior fusion. This should be preserved with caution for selected patients. The purpose of surgery for spinal stenosis is to allow the patient to walk longer distances without pain. If an elderly individual is not able to walk distances, the
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tendency is to become wheelchair or bed-ridden. Immobility results in muscle atrophy, osteoporosis, and loss of social contacts and can seriously affect the physical and mental health of the patient (Bridwell, 1994). We used the Oswestry index category (Fairbank et al., 1980) for evaluating the surgical outcome. In general, improvement was noted in 85% of the patients in this series following surgery. Good to excellent results were noted for 80% of the patients, while 11 and 9% reported moderate and poor results, respectively. This correlates with other reported results of 60–85% improvement, either in studies who deal with elderly (Sanderson and Wood, 1993; Jonsson and Stromqvist, 1994) or those considering population in diversity of ages (Turner et al., 1992; Herno et al., 1994), though most of the other articles contain data for heterogeneous ages, including young patients. Surgical treatment is superior to conservative treatment, which cause improvement in only 15% of the patients, and stabilization or deterioration in 70 and 15% of the patients, respectively, each year (Katz et al., 1996). The complication rate in this series was 26% (12 out of 46 patients Table 3), among them 15% (seven patients) general complications and 11% (five patients) specific complications of spine surgery. No mortality was noted. This rate of complications is higher than other published data which report about 10% complication rates (Smith and Lawrence, 1991; Deyo et al., 1992; Turner et al., 1992; Bridwell, 1994; Ciol et al., 1996). This phenomenon can be explained by the relatively older age of our patients, who are more prone to complications. In summary, the surgical treatment for spinal stenosis in elderly patients, who suffer intractable pain, and walking distance limitation, has a high rate of success. The vast majority of our patients would have undergone the operation if they had known the outcome in advance. Surgical treatment in spinal stenosis reduced the pain, increased walking distance, increases ADL performance and improved social activities in the elderly (up to 6 years after surgery in our series). The operative success was not decreased in the very old patients (over 75 years), and is not related to sex, background disease, nor to the number of segments involved, neurological signs or duration of the disease. Therefore, surgical treatment should be considered favorably and early in elderly patients, as a treatment option, in order to obtain the best results.
References Atlas, S.J., Deyo, R.A., Keller, R.B., Chapin, A.M., Patrick, D.L., Long, J.M., Singer, D.E., 1996. The Maine lumbar spine study, part III: 1-year outcomes of surgical and nonsurgical management of lumbar spinal stenosis. Spine 21, 1787 –1794. Bridwell, K.H., 1994. Lumbar spinal stenosis. Diagnosis, management and treatment. Clin. Geriatr. Med. 10, 677 – 701. Cinotti, G., Postacchini, F., Weinstein, J.N., 1993. Lumbar spinal stenosis and diabetes. Outcome of surgical decompression. J. Bone Joint Surg. [Br] 76, 215 – 219. Ciol, M.A., Deyo, R.A., Howell, E., Kreif, S., 1996. An assessment of surgery for spinal stenosis: time trends, geographic variations, complications, and reoperations. J. Am. Geriatr. Soc. 44, 285 – 290.
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Deyo, R.A., Cherkin, D.C., Loeser, J.D., Bigos, S.J., Ciol, M.A., 1992. Morbidity and mortality in association with operations on the lumbar spine. The influence of age, diagnosis and procedure. J. Bone Joint Surg. [Am] 74, 536 –543. Fairbank, J.C., Mbaot, J.C., Davies, J.B., Oebrien, J.P., 1980. The Oswestry low back pain disability questionnaire. Physiotherapy 66, 271 – 273. Herno, A., Airaksinen, O., Saari, T., 1994. Computed tomography after laminectomy for lumbar spinal stenosis. Patients’ pain patterns, walking capacity, and subjective disability had no correlation with computed tomography findings. Spine 19, 1975 –1978. Johnsson, K.E., 1995. Lumbar spinal stenosis. A retrospective study of 163 cases in southern Sweden. Acta Orthop. Scand. 66, 403 –405. Jonsson, B., Stromqvist, B., 1993. Symptoms and signs in degeneration of the lumbar spine. A prospective, consecutive study of 300 operated patients. J. Bone Joint Surg. [Br] 75, 381 – 385. Jonsson, B., Stromqvist, B., 1994. Lumbar spine surgery in the elderly. Complications and surgical results. Spine 19, 1431 –1435. Johnsson, K.E., Rosen, I., Uden, A., 1992. The natural course of lumbar spinal stenosis. Clin. Orthop. 279, 82 – 86. Joyce, C.R.B., Zutshi, D.W., Hrubes, V., Mason, R.M., 1975. Comparison of fixed interval analogue scales for rating chronic pain. Eur. J. Clin. Pharmacol. 8, 415 – 420. Katz, J.N., Lipson, S.J., Chang, L.C., Levine, S.A., Fossel, A.H., Liang, M.H., 1996. Seven to 10 year outcome of decompressive surgery for degenerative lumbar spinal stenosis. Spine 21, 92 – 98. Maravilla, K.R., Lesh, P., Weinreb, J.C., Selby, D.K., Mooney, V., 1985. Magnetic resonance imaging of the lumbar spine with CT correlations. Am. J. Neuroradiol. 6, 237 – 245. Niggemeyer, O., Strauss, J.M., Schulitz, K.P., 1997. Comparison of surgical procedures for degenerative lumbar spinal stenosis: a meta-analysis of the literature from 1975 – 1995. Eur. Spine J. 6, 423 – 429. Onel, D., Sari, H., Donmez, C., 1993. Lumbar spinal stenosis: clinical/radiologic therapeutic evaluation in 145 patients. Spine 18, 291 –298. Sanderson, P.L., Wood, P.L., 1993. Surgery for lumbar spinal stenosis in old people. J. Bone Joint Surg. [Br] 75, 393 – 397. Schonstrom, N.S.R., Bolender, N.F., Spengler, D.M., 1985. The Pathomorphology of spinal stenosis on CT scans of the lumbar spine. Spine 10, 806–811. Smith, D.W., Lawrence, B.D., 1991. Vascular complications of lumbar decompression laminectomy and foraminectomy. A unique case and review of the literature. Spine 16, 387 – 390. Spengler, D.M., 1987. Degenerative stenosis of the lumbar spine. J. Bone Joint Surg. [Br] 69, 305 – 308. Turner, J.A., Ersek, M., Herron, L., Deyo, R., 1992. Surgery for lumbar spinal stenosis —attempted meta-analysis of the literature. Spine 17, 1 –8. Verbiest, H., 1977. Results of surgical treatment of idiopathic developmental stenosis of the lumbar vertebral canal, a review of twenty-seven years experience. J. Bone Joint Surg. [Br] 59, 181 – 189.
Surgical treatment of lumbar spinal stenosis in patients aged 65 years and older S. Shabat a,*, Y. Leitner a, M. Nyska a, Y. Berner b, B. Fredman c, R. Gepstein a a Spine Unit, Orthopaedic Surgery Department, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel b Department of Geriatrics, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel c Department of Anesthesiology, Sapir Medica Center, and Tel-A6i6 Sourasky Medical School, 48 Tchernicho6sky St., Kfar-Saba 44281, Tel-A6i6, Israel
Received 18 July 2001; received in revised form 10 January 2002; accepted 11 January 2002
Abstract Spinal stenosis syndrome affects mainly patients at their 5th– 6th decades of life. The main goals of surgical treatment in the elderly are to allow the individual to walk longer distances, maintain the activities of daily living (ADL) and social life. Our aim was to evaluate the results of surgical treatment for lumbar spinal stenosis in elderly patients. All patients over 65 years of age who underwent surgery due to spinal stenosis syndrome between 1990 and 1998 were evaluated. There were 29 males and 17 females aged between 65 and 90 years. The clinical presentation included low back pain (89%), intermittent claudication (100%) and neurological involvement (87%). The radiological examination showed a frequent narrowing at the level L4–L5 in 93.5% of the patients. The results of the surgery in a mean follow-up of 22 months were good to excellent in 80% of the patients, fair in 11%, and poor in 9%. An improvement in the intensity of pain and in walking distances was noted in 89 and 85% of the patients, respectively. Improvement was achieved in the level of daily activity and in social lives in 57 and 61%, respectively. Major and minor complication rates were 6.5 and 19.5%, respectively. No mortality was noted in this series. Eighty-seven percent of the patients were satisfied with the results of the surgery. We conclude that Surgery for spinal stenosis is a successful and relatively safe procedure, also for patients aged over 65, and should be considered as a treatment option for these patients. © 2002 Elsevier Science Ireland Ltd. All rights reserved. * Corresponding author. Tel.: + 972-9-7472549; fax: +972-9-7423230. E-mail address: [email protected] (S. Shabat). 0167-4943/02/$ - see front matter © 2002 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 1 6 7 - 4 9 4 3 ( 0 2 ) 0 0 0 1 6 - X
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Keywords: Spinal stenosis; Elderly; Surgery; Rehabilitation
1. Introduction A lumbar spinal stenosis syndrome results from narrowing of the spinal canal, nerve root canal, or the intervertebral foramen leading to compression of the spinal cord or the nerve roots (Onel et al., 1993; Johnsson, 1995). The clinical syndrome presents in the 5th– 6th decades and includes: low back pain, intermittent claudication, morning stiffness, and neurological involvement. The neurological symptoms include muscular weakness, paresthesia, hypo-aesthesia, hypo-reflexia, and rarely incontinence. The pathophysiology of this syndrome is a degenerative process of the facets (Onel et al., 1993; Johnsson, 1995). The diagnosis is established by computerized tomography (CT) and magnetic resonance imaging (MRI) (Maravilla et al., 1985; Schonstrom et al., 1985). The conservative treatment includes bed-rest, analgesics, non-steroidal anti-inflammatory drugs, physiotherapy, ultrasound, and epidural facet blocks (Spengler, 1987; Onel et al., 1993; Atlas et al., 1996). Nevertheless, the treatment of choice in cases with severe stenosis is decompressive laminectomy, known to have good results and a low rate of complications (Verbiest, 1977). The syndrome in the elderly might increase morbidity and mortality due to side effects of the conservative treatment, reduced activity or sequella of recumbancy. Surgical treatment might prevent these sequella and improve the quality of life even in the elderly (Bridwell, 1994). In the elderly group of patients, the clinical symptoms can be more pronounced, and the surgical treatment is often more complicated (Ciol et al., 1996). This work is a retrospective case study aimed to evaluate the results of the surgical treatment in elderly patients over 65 years of age and the factors that may affect these results.
2. Patients and methods All patients over the age of 65 years, who were operated for lumbar spinal stenosis during the years 1990– 1998 in our medical center, were enrolled in this study. Each patient underwent evaluation that included history taking, physical examination, plain X-ray films, CT scan and/or MRI of the lumbar spine. Twentytwo patients suffered from background diseases, which included mild congestive heart failure (n= 4), arrhythmia (n = 3), hypertension (n =9), non-insulin dependent diabetes mellitus (n =2), mild chronic obstructive pulmonary disease (n= 2), mild chronic renal failure (n= 3) and peripheral vascular disease (PVD) (n= 5). Twelve patients used to smoke regularly before the operation. Nineteen patients out of the 22 used to take drugs to control their background disease. All patients underwent decompressive laminectomy. Foraminotomy or facetectomy were added
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according to the surgeon’s decision at operation. In some of the patients, a discectomy was needed as well. One patient needed a fusion procedure. Twenty-five patients were discharged at the day of operation or 1 day afterwards. Ten and four patients were discharged 2 and 3 days after the operation, respectively, and the remaining seven patients were discharged 4 days or more after the operation. All patients were followed post-operatively and underwent repeated physical examinations, for pain, function and neurological damage. The follow-up periods varied from 2 to 76 months after the operation (mean, 22 months). We used the Oswestry index category for evaluating the following parameters before and after operation (Fairbank et al., 1980). (A) intensity of pain was used by the visual analogue scale (VAS) score (Joyce et al., 1975); (B) the use of analgesics (absence of analgesics, use of analgesics with a total relief, use of analgesics with partial relief, use of analgesics without any relief); (C) maximal walking distance (walking any distance, walking up to 1 km, walking up to 500 m, walking only few meters or using a cane or a walker); (D) the need of help with activities of daily living (ADL) (individual is capable of taking care of himself, need of only little help with ADL, need of a daily-basis help in most of ADL, individual is not capable of clothing, bathing, etc. without being helped); (E) participation in social life (maximal social life as defined by the patient, only a slight reduction in social life in comparison with a maximum definition, limited social life, not having any social life). The neurological impairment was measured (according to history and physical examination), which included straight leg raising (SLR) tests and motor, sensory, reflex and continence. This was noted before and after the operation, and whether there was improvement (full or partial), unchanged condition, or even deterioration. Motor examination was measured on a scale of 0–5 (0, no evidence of contractility; 1, evidence of slight contractility, but no joint motion, 2, complete range of motion with gravity eliminated; 3, complete range of motion against gravity; 4, complete range of motion against gravity with some resistance; 5, complete range of motion against gravity with full resistance). Sensory examination was performed according to the sensation in the affected area before and after the operation, and whether it was fully recovered to full sensation, partially recovered, not changed or deteriorated. Complications after surgery were assessed as well (infection (deep or superficial), any permanent residual neurological damage, dural tear, other complications and death). In addition all patients were asked about their satisfaction from the operation and their willingness to undergo the operation if they had known in advance the operative results.
2.1. Statistical analysis Statistical analysis was done by the SPSS data processing program. In order to compare differences among the various groups of patients, the Student’s t-test was performed for independent variables at two levels. For three or more levels the one-way analysis of variance test followed by a Scheffe post hoc test was performed. In the case of variables that were analyzed from scales that may not result in equal interval data, the Pearson correlation coefficient test was employed.
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3. Results Forty-six patients more than 65 years of age were operated due to lumbar spinal stenosis in our institution between 1990 and 1998. These patients comprise this study. The age of the patients at time of operation ranged between 65 and 90 years (median 72 years). Sixteen patients were between 65 and 69 years old (35%), 17 patients were between 70 and 74 years of age (37%), and the remaining 13 patients were more than 75 years old (28%). Seventeen out of the 46 patients (37%) were females, and 29 patients (63%) were males. Major background diseases included PVD which was noted in five of the patients, non-insulin diabetes mellitus in two patients, and 12 patients used to smoke regularly before the operation. The clinical symptoms and signs of the spinal stenosis among the patients are summarized in Table 1. These symptoms affected the patients between 5 days and 40 years prior to operation (median, 36 months). All patients underwent CT and/or MRI imaging evaluation for the spinal stenosis. Forty-three patients (94%) had spinal stenosis at the L4– L5 level, followed by 21 patients (46%) at L3– L4 level, 13 patients (29%) had spinal stenosis at L5– S1 Level, ten patients (22%) at L2– L3 level and two patients (4%) at L1– L2 level. The number of segments involved varied from 1 to 4. Seventeen patients had one level and 17 patients had two levels of segmental involvement. Three segmental involvement was noted in ten of the patients and only two patients had four segmental involvement. The number of the involved segments was not influenced by the age of the patients, nor was it correlated with the intensity of the clinical symptoms (P\0.05). In a multi-segmental stenosis, there was a higher tendency of neurological impairment but this was not statistically significant. Table 1 The clinical symptoms and signs of the spinal stenosis Clinical symptoms and signs
Number of patients
Low back pain Intermittent claudication Neurological impairment Motor impairment alone Sensory impairment alone Reduction in reflexes (general) Decrease ankle reflex alone Decrease patellar reflex Urine incontinency Anal incontinency Intact SLR examination Positive SLR test (unilateral) Positive SLR test (bilateral)
41 46 40 18 33 28 27 14 1 1 29 5 12
(89%) (100%) (87%) (39%) (72%) (61%) (59%) (31%) (2.2%) (2.2%) (63%) (11%) (26%)
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Table 2 The change in motor and sensory examination in patients with respective deficits prior to operation Change
Motor examination
Sensory examination
Full improvement (5/5) Partial improvement No change Reduction Total
10 (55%) 3 (17%) 3 (17%) 2(11%) 18 (100%)
19 6 6 2 33
(58%) (18%) (18%) (6%) (100%)
Thirty-one patients (67%) underwent decompressive laminectomy alone. Fourteen additional patients (30%) had discectomy in addition to the decompressive laminectomy, and one patient (2%) had a combination of decompressive laminectomy, and one patient (2%) had a combination of decompressive laminectomy and fusion. Twenty nine (63%) and eight (17%) of the patients had estimated intensity of pain of ten and nine, respectively, prior to the operation. The average VAS score before the operation was 8.64 and was reduced to 3.34 post operatively (PB 0.0001). Forty-one patients had improvement in their subjective pain, while one patient had no change and four patients had increased pain post-operatively. No correlation was found between smoking and degree of pain or pain improvement by the operation. Patients with PVD suffered more from pain pre-operatively (PB 0.05). In addition they had less improvement in terms of subjective pain than the other patients (P B 0.05). Patients who had multi-level stenosis had more improvement in pain after the operation (P B0.05). The vast majority of patients used analgesics prior to operation, and most of them reported no pain relief; while after the operation most of the patients (41 out of 46 patients) did not need to use analgesics. The operation improved the walking distance capacity (PB 0.05). Thirty-nine patients (85%) had improvement in walking distance due to the operation. Three patients (6%) could ambulate to the same distance, and four patients (9%) had reduction in walking distance after the operation. No relation was found between diabetes or PVD to the improvement in walking distance. Twenty-six patients (57%) had improvement in ADL performance, 18 patients (39%) had the same ADL performance before and after the operation, and two patients (4%) had reduction in ADL performance (PB 0.01). Social life performance was also improved significantly after the operation (PB 0.01). Prior to the operation, 64% of the patients had restriction in their social life activities, while after the operation only 17% of the patients were restricted in any means in their social life. The change in motor and sensory examination in patients with respective deficits prior to the operation is summarized in Table 2. Three patients with intact muscle strength before the operation developed partial muscle weakness (4/5) after the operation. No relation was found between the elapsed time until the operation to the motor improvement. Three patients (6.5%)
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with intact sensory examination developed partial sensory deficits after the operation as well. Two patients who were incontinent prior to operation returned to full continence after the procedure. In 38 patients the straight leg-raising (SLR) test was normal after the operation. Among these patients, 95% showed improvement of SLR, and 5% showed no change in the SLR test. In the remaining eight patients with positive SLR test after the operation, 37.5% showed improvement, and 25 and 37.5% showed no change and exacerbation, respectively, in this test in relation to the examination prior to operation. In the last group of eight patients with pathological SLR test that was noted after the procedure the overall result of the operation was poorer than those with normal SLR. Four patients had normal SLR before the operation, which became positive after it. None of these patients showed improvement due to the operation. Nine minor operative complications were recorded (19.5%) and included superficial wound infection, atalectasis, urinary tract infection, residual neurological damage and dural tear. Major operative complications were noted in three patients (6.5%) and included pulmonary emboli, myocardial infarction and permanent neurologic injury. Complications are summarized in Table 3. The patients who had dural tear did not have neurological signs. Patients who were operated for one segment had fewer complications than patients who were operated for multi-segment stenosis (P B 0.05). No correlation was found between the background diseases (diabetes, smoking and PVD) and the complication rate. Fourteen (30%) and 23 (50%) of the patients showed excellent and good results, respectively; five (11%) and four (9%) patients had fair and poor results, respectively, following the operation. The satisfaction scale rate of the patients after the operation is summarized in Table 4. No differences were found between the different age groups and sex of the patients and their satisfaction with the outcome. Patients over age 75 years old showed the same results as the other age groups.
Table 3 Minor and major complications Minor complication
Number of patients
Major complications
Number of patients
Superficial wound infection Atalectasis Urinary tract infection
2 (4.3%) 1 (2.2%) 2 (4.3%)
Pulmonary embolism Myocardial infarction Permanent neurologic damage
1 (2.2%) 1 (2.2%) 1 (2.2%)
Residual neurologic damage Dural tear Total
2 (4.3%) 2 (4.3%) 9 (19.5%)
Total
3 (6.5%)
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Table 4 Satisfaction scale rate of the patients after the operation Satisfaction
Number of patients
Very satisfied Pretty satisfied Not so satisfied Unsatisfied Total
25 15 3 3 46
(54%) (33%) (6.5%) (6.5%) (100%)
4. Discussion This survey comprises 46 elderly patients (more than 65 years old) who underwent operation due to spinal stenosis. Spinal stenosis is considered to be increased as a cause for low-back and lower-extremity pain, especially in the elderly group of patients. Today, spinal stenosis is the leading diagnosis among elderly patients who undergo spine operation (Turner et al., 1992). However, the usual symptoms of spinal stenosis are often considered either by the primary care physician or by the elderly patient himself, as part of the natural process of aging, which one should live with, for the rest of his life. The primary care physician often tend not to send the elderly patient to a spine specialist, or to offer him operation because of the fear from complications and mortality. Some reports have documented that the success rate of these operations in this group of patients is the same as for young patients, and with minimal mortality (Johnsson et al., 1992; Turner et al., 1992). Even in octogenarians good results were reported for 85% of the cases with low morbidity (Bridwell, 1994). Failed conservative treatment without operative option in the elderly group of patients can eventually lead to reduced activity, immobility with its consequences and eventually reduced quality of life. Least invasive surgical procedure can obtain the best results if the correct diagnosis is made, and if the operation is carried out within the first years of the disease (Niggemeyer et al., 1997). This conclusion is of great benefit to elderly, who may have a higher complication rate. However, in the elderly, early diagnosis of spinal stenosis is more difficult to establish, because of the bewildering medical problems and multiple symptoms noted in physical and mental polymorbidity of old age. The clinical symptoms in our group of patients were similar to the symptoms reported in the literature. The vast majority of the patients suffered from low back pain. This is considered to be the first noticeable symptom (Jonsson and Stromqvist, 1993). Neurogenic claudication is usually expressed by pain radiating to the buttocks, thigh, leg or sometimes the foot, exacerbated by physical activities such as walking mainly downhill (Jonsson and Stromqvist, 1993). The pain is exacerbated by physical activity usually while walking a distance. In our series all patients suffered from neurogenic claudication. It is important to distinguish the neurogenic claudication from vascular claudication. In the latter, the pain stops immediately when resting, and in spinal stenosis the pain is relieved while perform-
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ing flexion of the lumbar spine (Jonsson and Stromqvist, 1993). Some authors advocate performing Doppler studies before deciding that the cause of the claudication is spinal rather than vascular (Bridwell, 1994). We did not perform these studies on a routine basis. A peripheral vascular cause of the leg pain was investigated only in patients with diminished pulses and reduced temperature and turgor of the lower extremities. Some of the patients in this series suffered from neurological deficits, mainly sensory and reduced ankle jerk, and to a lesser extent motor deficit. Since the stenosis develops gradually over the years, there is time for accommodation of the neural tissue, and thus even a severe stenosis can cause only mild neurologic sequela (Spengler, 1987). About two thirds of our patients (29 out of 46 Table 1) had intact SLR test. This test is usually positive in about 50% of the young patients (Turner et al., 1992; Jonsson and Stromqvist, 1993; Onel et al., 1993). However, in the elderly group of patients, it is unusual for them to have any nerve root tension signs presented as negative SLR, as are seen in younger patients with lumbar disc herniations (Bridwell, 1994). Only few patients in this series had incontinence, which is in correlation to a severe long-standing stenosis. No relation was found between the background disease such as diabetes, PVD, or smoking to the neurologic damage. This is supported by Cinnoti et al., who examined the relation between lumbar spinal stenosis and diabetes (Cinotti et al., 1993). The fact that no deterioration was found in this sub-group of patients can be explained by the small number of patients in our series who suffered from these background conditions. Multi-level stenosis, often bilateral, is the common presenting feature. The L4 –L5 and L3 –L4 segments are the most common involved. The least frequent are L5 –S1 and T12–L1 (Spengler, 1987; Bridwell, 1994). In this study the most common involved segments were L4– L5 and L3 – L4 as reported in the literature. However, the L5– S1 segment was the third to be involved in frequency, and that is contrary to the assumption that it is stabilized by the iliotransverse ligament. This series represents only the operated patients and not all patients with spinal stenosis. Another explanation is that in the elderly patients the ilioinguinal ligament is relatively weakened and can cause instability leading to stenosis of this level. The mainstay of surgical treatment is the appropriate posterior decompression. Some patients with deformities may also require posterior fusion and posterior instrumentation (Bridwell, 1994). Out of the 46 patients presented here only one underwent fusion. Even though a higher rate of re-narrowing is noted if a fusion is not performed, the rehabilitation without a fusion is much shorter, and the patient may be back to his or her previous activity level by 2 months postoperatively, in comparison to a closer to a year if fusion and instrumentation are used (Bridwell, 1994). The complication rate was found to be higher in a large metaanalysis performed on studies which were done over a 20 year period (Niggemeyer et al., 1997). Since in this series we deal with elderly patients, and theirreturn to normal life should be as fast as possible, we do not advocate liberal use of posterior fusion. This should be preserved with caution for selected patients. The purpose of surgery for spinal stenosis is to allow the patient to walk longer distances without pain. If an elderly individual is not able to walk distances, the
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tendency is to become wheelchair or bed-ridden. Immobility results in muscle atrophy, osteoporosis, and loss of social contacts and can seriously affect the physical and mental health of the patient (Bridwell, 1994). We used the Oswestry index category (Fairbank et al., 1980) for evaluating the surgical outcome. In general, improvement was noted in 85% of the patients in this series following surgery. Good to excellent results were noted for 80% of the patients, while 11 and 9% reported moderate and poor results, respectively. This correlates with other reported results of 60–85% improvement, either in studies who deal with elderly (Sanderson and Wood, 1993; Jonsson and Stromqvist, 1994) or those considering population in diversity of ages (Turner et al., 1992; Herno et al., 1994), though most of the other articles contain data for heterogeneous ages, including young patients. Surgical treatment is superior to conservative treatment, which cause improvement in only 15% of the patients, and stabilization or deterioration in 70 and 15% of the patients, respectively, each year (Katz et al., 1996). The complication rate in this series was 26% (12 out of 46 patients Table 3), among them 15% (seven patients) general complications and 11% (five patients) specific complications of spine surgery. No mortality was noted. This rate of complications is higher than other published data which report about 10% complication rates (Smith and Lawrence, 1991; Deyo et al., 1992; Turner et al., 1992; Bridwell, 1994; Ciol et al., 1996). This phenomenon can be explained by the relatively older age of our patients, who are more prone to complications. In summary, the surgical treatment for spinal stenosis in elderly patients, who suffer intractable pain, and walking distance limitation, has a high rate of success. The vast majority of our patients would have undergone the operation if they had known the outcome in advance. Surgical treatment in spinal stenosis reduced the pain, increased walking distance, increases ADL performance and improved social activities in the elderly (up to 6 years after surgery in our series). The operative success was not decreased in the very old patients (over 75 years), and is not related to sex, background disease, nor to the number of segments involved, neurological signs or duration of the disease. Therefore, surgical treatment should be considered favorably and early in elderly patients, as a treatment option, in order to obtain the best results.
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