Preoperative predictors for good postoperative satisfaction and functional outcome in lumbar spinal stenosis surgery--a prospective observational study with a two-year follow-up.

BACKGROUND AND AIMS: Lumbar spinal stenosis (LSS) is the most frequent indication for back surgery in adults aged over 65 years, but about one-third of operated patients have less than good/excellent results from the operation. Awareness of outcome predictors and their predictive values may help clinicians in their assessment of the prognosis of patients when considering surgical treatment. Our aim was to study the preoperative predictors in LSS for a good postoperative outcome (satisfaction with surgery and functional improvement) with a two-year follow-up. MATERIAL AND METHODS: LSS patients (n = 102) completed a questionnaire preoperatively and on two-year follow-up. Preoperative patient-related predictors, self-rated health, comorbidities and preoperative treatment were assessed. Satisfaction with the surgical outcome was assessed with a seven-category scale; satisfaction was determined to be good if the patient response was "condition has considerably improved" or "totally cured". Other responses ("condition has slightly improved" or worse) represented poorer satisfaction. A good functional outcome was determined as >30% relative improvement compared to the presurgery score in the Oswestry Disability Index (ODI). RESULTS: The predictors for good satisfaction were age < 75 years at operation (OR 4.03; 95% CI 1.35-12.02; p = 0.012) and no previous lumbar operation (OR 3.65; 95% CI 1.13-11.79; p = 0.031). Predictors for a good improvement in the ODI score were regular preoperative analgesic use < 12 months (OR 3.40; 95% CI 1.21-9.53; p = 0.020), non-smoking (OR 3.47; 95% CI 1.09-11.03; p = 0.035) and good (above average) self-rated health (OR 3.27; 95% CI 1.06-10.12; p = 0.039). CONCLUSIONS: In LSS, regular analgesic treatment preoperatively for 12 months or less, self-rated health above average and non-smoking predicted a good postoperative functional improvement. An age under 75 years and no previous lumbar operation predicted good post-operative satisfaction with the surgery.

Monitoring of muscle fatigue during isokinetic exercise.

The aim of this study was to evaluate and clarify the usefulness of different spectral characteristics of myoelectrical activity in the follow-up of development of muscle fatigue. Vastus lateralis (part of quadriceps) muscle loaded in a simple isokinetic exertion test was used as a model. Twelve, well trained athletes served as study subjective to minimize the inter-individual variations. They went through one-minute test with isokinetic device at the range of 90 degrees extension and flexion at the level of their maximal force. The myoelectrical signals were registered from middle of the vastus lateralis muscle by a computerized fast Fourier transform analyzing system based on 80286 and 80287 microprocessors and using surface electrodes. Mean power frequency (MPF) was 65.6 (SE=Standard Error, 1.6) Hz, median frequency (MF) 55.8 Hz and zero crossing rate (ZCR) 92.5 (SE 1.5) during first performance. All these parameters decreased apparently linearly and significantly from the beginning of the test (P<0.001). The decrease rate of ZCR was fastest and MF slowest. The area of power spectrum (PSA) was 1753 (SE 320) units during first performance, and it increased markedly with slightly accelerating rate during the test. In conclusion, for the evaluation of the muscular performance during the development of fatigue it is beneficial to monitor simultaneously MPF, MF and ZCR.

Late correlative imaging findings of previous acute infective spondylitis.

PURPOSE: To evaluate late correlative imaging findings in relation to clinical outcome in persons with previous acute infective spondylitis, the authors performed bone and leukocyte scintigraphy (planar and SPECT imaging) and magnetic resonance imaging of the spine in nine patients (two men, seven women; mean age, 66 years; age range, 57 to 84 years) 3.1 years (range, 0.9 to 6.2 years) after the acute disease. METHODS: All images were evaluated visually. The relevant uptake on SPECT images was also quantitated using an adjacent normal vertebral body as the reference area. RESULTS: Except for one patient, all other patients had increased uptake in the affected vertebra on bone scintigraphy [corrected]. In leukocyte scintigraphy, clearly decreased uptake was noted quantitatively in six of the seven patients who underwent SPECT. On the magnetic resonance and computed tomographic scans, the typical findings were destruction of intervertebral disks and compression deformities of vertebral bodies, but there was high interindividual variance of other findings, such as osteophytes, spondylolisthesis, increased vertebral fat content, and postoperative changes. These data show that nearly all patients with previously acute infective spondylitis have gross abnormal anatomic and functional imaging findings years after the acute disease, despite good clinical outcome [corrected]. CONCLUSIONS: The utility of bone and leukocyte scans in the diagnosis of reactivated spondylitis is limited, and incidentally observed abnormal imaging findings in asymptomatic patients with known previous spondylitis should be interpreted with caution.

Computed tomography findings 4 years after surgical management of lumbar spinal stenosis. No correlation with clinical outcome.

STUDY DESIGN: A prospective, cross-sectional study of the correlation between postoperative computed tomography findings and patients' clinical outcomes approximately 4 years after laminectomy for lumbar spinal stenosis. OBJECTIVES: To evaluate clinical and radiologic characteristics and their relation to each other. SUMMARY OF BACKGROUND DATA: The goal of surgical management for lumbar spinal stenosis is to decompress the stenotic area determined in radiologic examinations to relieve pressure on the neurovascular structures. However, the success of this decompression very rarely has been confirmed by postoperative radiologic imaging or compared with clinical outcome. METHODS: Postoperative computed tomography was performed on 191 patients. The findings were classified as "no stenosis," "central stenosis," "lateral stenosis," or "central-lateral stenosis." Postoperative instability of the lumbar spine was investigated by functional radiography. Clinical status was assessed by clinical examination. Subjective disability was assessing using the Oswestry questionnaire, and severity of pain using the visual analog scale. Walking capacity was evaluated by the tread-mill test. RESULTS: Radiologic studies revealed postoperative stenosis in 123 patients (64%). Small differences between the computed tomography groups were shown for the Oswestry score, but not for walking distance. Clinical signs, severity of pain, and radiologic instability were very similar for all computed tomography groups. CONCLUSIONS: Postoperative radiologic stenosis was very common in patients operated on for lumbar spinal stenosis, but this did not correlate with clinical outcome. The clinician must be cautious when reconciling clinical symptoms and signs with postoperative computed tomography findings in patients operated on for lumbar spinal stenosis.

Long-term clinical and magnetic resonance imaging follow-up assessment of patients with lumbar spinal stenosis after laminectomy.

STUDY DESIGN: A cross-sectional retrospective study to observe the correlation between postoperation findings shown on magnetic resonance imaging and clinical observations of 56 patients 10 years after laminectomy for lumbar spinal stenosis. OBJECTIVE: To evaluate the relation between postoperation findings on magnetic resonance imaging and surgical outcome in patients surgically treated for lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Surgical management of lumbar spinal stenosis is based on the compression seen in radiologic imaging of neurovascular structures in the vertebral canal, but the success of surgical decompression and its correlation with clinical observations very seldom have been monitored by postoperation radiologic imaging. METHODS: In this study, 56 patients surgically treated for lumbar spinal stenosis were re-examined clinically by use of the Oswestry disability questionnaire. Their walking capacity was evaluated by the treadmill test. Severity of pain before and after the treadmill test was investigated using a visual analog scale. Patients' perception of improvement measured as the change in their condition during the preceding 5 years was elicited by a questionnaire. On the basis of the stenotic findings on magnetic resonance imaging, the patients were classified into no stenosis (NoSten, n = 15) and stenosis (Sten, n = 41) groups, and a summative degenerative scale also was constructed with the findings categorized as follows: disc degeneration, disc herniation, facet joint arthrosis, and degenerative spondylolisthesis. RESULTS: Whereas the patients' perception of improvement correlated very strongly with the Oswestry score and walking capacity, there was no statistical difference between the NoSten and Sten groups in the Oswestry score, walking capacity, perception of improvement, or severity of pain. The effect of the summative degenerative scale on the patients' walking capacity was 13 times greater than the effect of the minimum area of the dural sac. CONCLUSIONS: Patients' perception of improvement had a much stronger correlation with long-term surgical outcome than structural findings seen on postoperation magnetic resonance imaging. Moreover, degenerative findings had a greater effect on patients' walking capacity than stenotic findings.

The degree of decompressive relief and its relation to clinical outcome in patients undergoing surgery for lumbar spinal stenosis.

STUDY DESIGN: A cross-sectional, clinical study to evaluate surgical decompression of the stenotic area monitored by computed tomographic scan and its relation to clinical variables in patients operated on for lumbar spinal stenosis. OBJECTIVE: To study in patients with lumbar spinal stenosis the influence of the degree of compressive relief on the patients' clinical outcome. SUMMARY OF BACKGROUND DATA: The goal of surgical treatment in lumbar spinal stenosis is to decompress the stenotic area. Although the decompression should be adequate, there are no clear guidelines to determine the extent of necessary decompression. In fact, there is clinical evidence that there is a discrepancy between the surgical outcome in the patient with lumbar spinal stenosis and postoperative radiologic findings. METHODS: In 92 patients with lumbar spinal stenosis who had had no prior back surgery, preoperative and postoperative computed tomographic scans were obtained to determine the degree of decompression. The postoperative scan findings were classified according to the degree of decompression into a no-stenosis group (n = 35), an adjacent-stenosis group (n = 27), and a residual-stenosis group (n = 30). The postoperative instability of the lumbar spine was investigated by functional radiography. The subjective disability of the patients was assessed using the Oswestry score and the severity of pain using the visual analog scale. Walking capacity was evaluated by a treadmill test. The patients' estimations of the results of surgery were classified into groups of satisfied patients and dissatisfied patients. RESULTS: The mean Oswestry score in all 92 patients was 27.1, and mean walking capacity was 630 m. In the satisfied patients, the Oswestry score was 18.8 and in the dissatisfied patients, 34.9 (P < 0.0000). Walking capacity was 690 m and 594 m, respectively. There were 30 patients with postoperative spinal instability, but it had no influence on surgical outcome. There were no differences in the Oswestry score, walking capacity, and patients' satisfaction among the postoperative CT groups. In the linear regression analysis, the satisfied patient corresponded significantly with the Oswestry score. CONCLUSIONS: The satisfaction of the patients with the results of surgery was more important in surgical outcome than the degree of decompression detected on computed tomographic scan.

Surgical outcome of 438 patients treated surgically for lumbar spinal stenosis.

STUDY DESIGN: A retrospective, follow-up study. OBJECTIVES: To investigate the overall outcome of surgery for lumbar spinal stenosis and to investigate the preoperative factors affecting outcome. SUMMARY OF BACKGROUND DATA: The success rates of surgical intervention for lumbar spinal stenosis vary, and few preoperative factors have been found to be significantly correlated to surgical outcome. METHODS: A total of 438 patients (183 women, 255 men) who underwent decompressive surgery for lumbar spinal stenosis were re-examined and evaluated for outcome 4.3 years after surgery. Outcome was based on subjective disability, which was assessed using the Oswestry low back pain questionnaire. The preoperative data (clinical documentation, length of laminectomy, and radiographs) were collected from patient records that had been stored in the hospital. Preoperative factors affecting outcome were reported. RESULTS: The mean value of the Oswestry disability score of these 438 patients was 34 +/- 18 (women, 36.3 +/- 17; men, 32.3 +/- 18; P < 0.05). Age did not influence general outcome. The proportion of good to excellent outcomes of all 438 patients was 62% (women, 57%; men, 65%). Diabetes, hip joint arthrosis, and preoperative fracture of the lumbar spine seemed to be associated with poor outcome. The ability to work before or after surgery and a history of no prior back surgery were predictive of good outcome. CONCLUSION: The results suggest that clear myelographic stenosis and no prior surgical intervention, no comorbidity of diabetes, no hip joint arthrosis, and no preoperative fracture of the lumbar spine are factors associated with a good outcome in surgical management of lumbar spinal stenosis.

Pre- and postoperative factors associated with return to work following surgery for lumbar spinal stenosis.

Low back disorders are an increasingly common and costly health problem in Western countries. It has been recommended that the return to work of patients should be the most important outcome measure of medical care. The aim of this study was to compare women's and men's working capacity after lumbar spinal stenosis (LSS) operations and to identify the factors related to it. The subjects of this study were 185 women (mean age 54 years, mean follow-up time 4.2 years) and 254 men (mean age 52 years, mean follow-up time 4.3 years). After the operation, 37% of the women and 41% of the men returned to work. None of the patients who had retired before the operation returned to work afterward. The variables that predicted postoperative ability to work for women were: being fit to work at the time of operation, age < 50 years at the time of operation, and duration of LSS symptoms < 2 years. For men, these variables were: being fit to work at the time of operation, age < 50 years at the time of operation, no prior surgery, and the extent of the surgical procedure equal to or less than 1 laminectomy. Women's and men's working capacity do not differ after LSS operation. If the aim is to maximize working capacity, then, when an LSS operation is indicated, it should be performed without delay. In LSS patients who are > 50 years old and on sick leave, it is unrealistic to expect that they will return to work. Therefore, after such an extensive surgical procedure, re-education of patients for lighter jobs could improve the chances of these patients returning to work.

Lumbar spinal stenosis: a matched-pair study of operated and non-operated patients.

The prevailing opinion seems to accept that the natural course of lumbar spinal stenosis is one of progressive worsening, and that only surgery can check this development. In fact, the choice of treatment for lumbar spinal stenosis is still an open question. The aim of this study was to compare in the matched-pair format the outcome of surgically and non-surgically treated patients with lumbar spinal stenosis. The surgically treated group consisted of 496 patients who were operated on during the period 1974-1987 and 440 of whom were re-examined an average of 4.1 years after surgery. The non-surgically treated group consisted of 57 patients who were treated conservatively during the period 1980-1987 and were re-examined an average of 4.3 years after the start of treatment. The matching criteria were sex, age, myelographic findings, major symptom and duration of symptoms. We were able to form 54 similar matched-pairs from the surgically and non-surgically treated patients. Subjective disability was assessed using the Oswestry questionnaire and functional status was evaluated during the clinical examination. For statistical analysis the McNemar test and the paired Student's t-test were used. The overall results showed no statistical difference in outcome between the matched-pair groups, but the operated men fared significantly better than the non-operated men. The functional status was very good in both groups and for both sexes. In conclusion, conservative treatment of lumbar spinal stenosis should be considered for the patients with moderate stenosis. Controlled, prospective and randomized trials are needed to clarify better the choice of treatment in patients with lumbar stenosis.

The effect of prior back surgery on surgical outcome in patients operated on for lumbar spinal stenosis. A matched-pair study.

It has been widely observed that the outcome after repeat lumbar surgery is rarely comparable to that of primary surgery. In particular, the results of repeat surgery for lumbar spinal stenosis (LSS) have not been favourable. We used a matched-pair format in an attempt to decrease the confounding factors so as to determine as exactly as possible the effect of prior back surgery on the LSS patients' surgical outcome. The matching criteria were sex, age, myelographic findings, major symptom, and duration of symptoms. From one group of 251 patients without prior back surgery (SO patients) and another of fifty-three patients with one preceding back operation (RS patients), forty-one similar matched patients pairs (one SO and one RS-patient) were formed. There were 8 female and 33 male pairs. The mean age of the SO patients was 51.6 and of the RS patient 51.4 years, and the mean follow-up time was 4.6 and 4.4 years. The assessment of outcome was based on a subjective disability questionnaire. The SO patients fared significantly better than the RS patients (32.1 versus 41.3, P = 0.026). A short time interval between operations in the RS patients had a worsening effect on outcome, but this trend was not significant. We concluded that one preceding back operation had a worsening effect on the outcome of patients operated on for LSS. As a whole, the results of RS patients were unfavourable. The proper time for achieving good surgical results in LSS patients is the initial operation.

Density of lumbar muscles 4 years after decompressive spinal surgery.

Results of decompressive surgery for lumbar spinal stenosis vary. We evaluated the density of lumbar muscles by computed tomography (CT) at the L2-L4 levels in patients 4 years after they had undergone surgery for lumbar spinal stenosis. Twenty of these patients had an excellent outcome clinically, and 16 patients had very poor outcome. The residual stenosis and density of lumbar muscles in Hounsfield units were measured on CT images. The clinical evaluation of outcome also included the Oswestry questionnaire and a walking test. The density of lumbar flexors was higher in the group with excellent results than in the group with poor results. The density of lumbar extensors showed a marked decrease in the operated area. These results suggest that the decrease of muscular density can be partially explained by disuse or inactivity. The decrease in the operated area probably reflects muscular atrophy caused by muscle denervation.

Surgical results of lumbar spinal stenosis. A comparison of patients with or without previous back surgery.

STUDY DESIGN: This retrospective study was designed to investigate the effects of previous back surgery in patients undergoing surgical procedure for lumbar spinal stenosis. OBJECTIVES: The authors evaluated the results of singly operated and repeat surgery patients operated on for lumbar spinal stenosis, and compared prognostic factors correlated with the results for these two groups. SUMMARY OF BACKGROUND DATA: Repeat back surgery is generally not as successful as a first operation, but few studies evaluate the effects of previous back surgery on the surgical outcome of patients with lumbar spinal stenosis. METHODS: The subjective disability of singly operated and repeat surgery patients as assessed by the Oswestry questionnaire was compared with clinical data and myelographic findings to identify factors predictive of outcome. RESULTS: The mean Oswestry score was 31.0 for singly operated patients and 40.9 for repeat surgery patients (P = 0.0001). The outcome was excellent-to-good in 67% of singly operated patients and in 46% of repeat surgery ones (P < 0.0017). Severe myelographic findings correlated significantly with good outcome in the singly operated group but not in the repeat surgery group. Coexisting disease contributed significantly to poor outcome in the repeat surgery group, but not in the singly operated group. The optimum time interval for achieving successful results from subsequent surgery is at least 18 months after previous surgery. In the regression analysis, the prognostic preoperative variables for good outcome was block stenosis on myelography in the singly operated patients and age over 50 years and no coexisting disease in the repeat surgery patients. CONCLUSIONS: Previous back surgery had a highly significant worsening effect on the outcome of patients reoperated on for lumbar spinal stenosis. Not even a very well-established diagnosis of lumbar spinal stenosis, as confirmed by myelography and during surgery, could guarantee as successful a surgical outcome in the repeat surgery patients as that in the singly operated patients.

Surgical results of lumbar spinal stenosis.

The purpose of this work was to evaluate the surgical results of lumbar spinal stenosis (LSS), and to find factors which influenced outcome. A total of 497 LSS patients fulfilled the inclusion criteria i.e. LSS was confirmed both radiologically and surgically, in the study period from 1974 to 1987. For various reasons 58 patients could not participate in the study, and hence, the results of this work were based on 439 surgically treated LSS patients. An excellent-to-good outcome was achieved in 62% of all patients with a mean follow-up time of 4.3 years. The prognostic factors for this result were able to work after surgery, able to work before surgery, no prior back surgery, age over 50 years, male sex, and leg pain. Of 86 patients who were working before surgery, 52 (60%) continued to work after operation, whereas of 223 patients who were on sick leave before surgery, 70 (31%) returned to work after operation. None of the preoperatively retired patients regained their ability to work postoperatively. The prognostic factors for ability to work after surgery were ability to work before surgery, age under 50 years, and no prior back surgery. The very long-term outcome (mean followup time of 12.4 years) was excellent-to-good in 68% of patients (59% women and 73% men). Furthermore, in the longitudinal follow-up, the result improved between 1985 (mean follow-up time 6.8 years) and 1991 (mean follow-up time 12.8 years). No special complications were manifested during this very long-term follow-up time. The patients with total or subtotal block in preoperative myelography achieved the best result. In this radiological category of LSS the proportion of patients with excellent-to-good outcome was very similar in women and men (73% and 77%). Furthermore, patients with block stenosis improved their result significantly in the longitudinal follow-up. The postoperative stenosis seen in computed tomography (CT) scans was observed in 65% of 90 patients, and it was severe in 23 patients (25%). However, this successful or unsuccessful surgical decompression did not correlate with patients' subjective disability, walking capacity or severity of pain. Previous back surgery had a strong worsening effect on surgical results. This effect was very clear in patients with total block in the preoperative myelography. The surgical result of a patient with previous back surgery was similar to that of a patient without previous back surgery when the time interval between the last two operations was more than 18 months.(ABSTRACT TRUNCATED AT 400 WORDS)

Computed tomography after laminectomy for lumbar spinal stenosis. Patients' pain patterns, walking capacity, and subjective disability had no correlation with computed tomography findings.

OBJECTIVES: The purpose of this study was to evaluate the relationship between postoperative computed tomography findings and patients' pain patterns, walking capacity, and subjective disability after laminectomy for lumbar spinal stenosis. SUMMARY OF BACKGROUND DATA: Recent improvements in computed tomography have enabled this tool to reveal changes in a patient after an operation, but there is a paucity of comparative examinations regarding the lumbar spinal canal of asymptomatic and symptomatic patients after laminectomy for lumbar spinal stenosis. METHODS: Ninety-two patients (42 women, and 50 men) with a mean age of 55 years were operated upon. Mean follow-up time was 3.5 years. Based on computed tomography findings of the operative area, three patient groups were formed: 1) no stenosis, 2) moderate stenosis, 3) and severe stenosis. During treadmill testing, each patient's pain was evaluated by visual analogue scale. The patients were divided into four pain pattern groups: 1) pain in the back and leg, 2) pain in the back only, 3) pain in the leg only, and 4) no pain in the back and leg. Subjective disability was measured by the Oswestry disability score. RESULTS: The structural changes revealed by computed tomography, and the patients' pain patterns, walking capacity, and subjective disability did not correlate significantly with each other. CONCLUSIONS: Postoperative computed tomography has only limited value because asymptomatic and symptomatic patients yield similar findings after surgery for lumbar spinal stenosis.

The predictive value of preoperative myelography in lumbar spinal stenosis.

STUDY DESIGN: Retrospective follow-up study on the significance of myelographic findings on the postoperative results of patients with lumbar canal stenosis is not well defined. OBJECTIVES: The authors studied the predictive influence of preoperative myelography on the outcome of patients with surgically treated lumbar spinal stenosis, defined by an upper limit of anteroposterior diameter of the dural sac on the lateral myelogram film of equal to or less than 12 mm. SUMMARY OF BACKGROUND DATA: Patients with prior lumbar surgery were excluded. There were 251 patients (women 44% and men 56%) with a mean age of 55 years and a mean follow-up time of 4.2 years. METHODS: Patients with complete block or subtotal block on myelography were included in the block stenosis group, patients with an anteroposterior diameter of less than 10 mm were included in the absolute stenosis group and patients with an anteroposterior diameter of 10-12 mm were included in the relative stenosis group. RESULTS: The proportion of good-to-excellent outcomes was 76% in block stenosis, 56% in absolute stenosis, and 61% in relative stenosis. In the multivariate analysis, the pre-preoperative variables that correlated with good outcome were block stenosis and male sex. CONCLUSIONS: The severity of myelographic findings is significantly related to the outcome of patients who underwent surgeries for lumbar canal stenosis.

Surgical treatment of lumbar spinal stenosis: patients' postoperative disability and working capacity.

A total of 439 patients operated on for lumbar spinal stenosis during the period 1974-1987 was re-examinated and evaluated for working and functional capacity approximately 4 years after the decompressive surgery. The assessment of subjective disability was based on the Oswestry low-back pain questionnaire. The proportion of excellent-to-good outcomes was 62% (women 57%, men 65%). The ability to work before or after the operation and a history of no prior back surgery were variables predictive of a good outcome. Before the operation 86 patients were working, 223 patients were on sick leave, and 130 patients were retired. After the operation 52 of the employed patients and 70 of the unemployed patients returned to work. None of the retired patients returned to work. In logistic regression analysis the ability to work preoperatively, age under 50 years at the time of operation and the absence of prior back surgery predicted a postoperative ability to work. Our results suggest that more attention should be focussed on the diagnosis of spinal stenosis and on the timing of the operative intervention.

The long-term prognosis after operation for lumbar spinal stenosis.

The prognosis for patients treated surgically for lumbar spinal stenosis with a minimum follow-up time of 10 years was evaluated. The study group consisted of 102 patients (39 women and 63 men) with a mean age at operation of 52 years and with a mean follow-up time of 12.4 years. The antero-posterior (AP) diameter was equal to or less than 12 mm at the narrowest point on the preoperative lateral myelograms. The results were based on the Oswestry disability score, the severity of pain, the change in pain and the state of depression. According to this score the results were excellent-to-good in 69 patients (68%), the pain was mild in 64 patients (63%), the change in pain was slight in 78 patients (77%), and there was no depression in 55 patients (54%). The pain and the change in pain had a very high correlation in the Oswestry disability score. The pain led to depression more often in the men than in the women. The depression had a much stronger correlation to outcome in the men than in the women.

Long-term results of surgical treatment of lumbar spinal stenosis.

There are few data available regarding the long-term outcome of laminectomy for lumbar canal stenosis. Both in 1985 and in 1991 108 patients who had undergone surgery for lumbar spinal stenosis were reevaluated using the Oswestry disability questionnaire. There were 50 women and 58 men. The clinical diagnosis of stenosis was confirmed mainly by myelography. The mean follow-up time in 1985 was 6.8 years and in 1991 12.8 years, and the mean age of the patients at the time of surgery was 50.7 years. The mean Oswestry score in 1985 was 34.5 and in 1991 30.2 (P < 0.001). Men improved more than women. Laminectomy was performed on an average of 1.6 levels. Ten (9.3%) of the 108 patients underwent repeat decompression during the study period. The authors concluded that the results of the patients improved during the course of the longitudinal follow-up time of 7 and 13 years. The chances of a patient requiring reoperation after surgery for lumbar spinal stenosis were low.