Long-Term Results of Minimally Invasive Transforaminal Lumbar Interbody Fusion in Elderly Patients: A 5-Year Follow-Up Study

Abstract

Study Design

Retrospective review of prospective data.

Objectives

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) may be beneficial for elderly patients due to decreased surgical morbidity and faster postoperative recovery. This study compared the clinical and radiological outcomes of MIS-TLIF in elderly patients and younger controls at minimum 5-year follow-up.

Methods

There were 120 patients who underwent single-level MIS-TLIF for degenerative spondylolisthesis. Elderly patients (≥70 years; n = 30) and controls (<70 years; n = 90) were matched 1:3 for demographics, comorbidities and preoperative patient-reported outcomes (PROs). The Oswestry Disability Index (ODI), 36-Item Short-Form Physical (SF-36 PCS) and Mental Component Summary (SF-36 MCS), Visual Analogue Scale (VAS) back pain, and VAS leg pain were compared at 6 months, 2 years and 5 years. Radiographic fusion, adjacent segment degeneration (ASD) and revision rates were assessed at mean 7.2 ± 2.0 years.

Results

Elderly patients had longer length of stay (4.7 ± 5.8 vs 3.3 ± 1.4 days, P = .035) and more readmissions (10% vs 1%, P = .019), but there was no difference in operative time, transfusions, complications or discharge disposition. All PROs were comparable at 5 years and satisfaction rates were similar (93% elderly vs 91% controls, P = .703). The rates of radiographic fusion in the control group and elderly group were similar (94% vs 97%, P = .605), as were the rates of ASD (40% vs 33%, P = .503). There were 3 revisions (3.3%) in the control group (2 for ASD, 1 for screw loosening) but none in the elderly group (P = .311).

Conclusions

Elderly patients undergoing MIS-TLIF achieved similar improvements in pain, disability and quality of life that were sustained at 5 years.

Level of Evidence: Level III, retrospective cohort study

Keywords

minimally invasive lumbar TLIF age elderly outcomes satisfaction adjacent segment disease

Introduction

With an aging population, the number of elderly patients requiring treatment for degenerative spinal conditions has been steadily increasing. Transforaminal lumbar interbody fusion (TLIF) is one of the most common surgical procedures to treat degenerative spondylolisthesis and spinal stenosis, which are major causes of pain and functional impairment in the older population.^1-3 In spite of this, many elderly patients are often overlooked as surgical candidates due to a higher comorbidity burden, ageism or subjective impressions regarding their fitness for surgery.⁴ Conversely, elderly patients are also often unwilling to undergo spinal surgery due to fears of an increased risk of perioperative complications or poorer surgical outcomes.

Previous studies have attempted to elucidate the impact of advanced age on spinal surgery outcomes.^5-8 One historical study found a near-threefold increase in the risk of complications in patients 75 years or older compared to younger controls undergoing open spinal surgery.⁹ However, recent technological advances in surgical instrumentation have led to the advent of minimally invasive spine (MIS) surgery, allowing a substantial reduction in incision length and soft-tissue disruption. Multiple studies have demonstrated comparable clinical and radiological outcomes following minimally invasive TLIF (MIS-TLIF) and open TLIF,^10-12 with the former procedure carrying additional benefits such as reduced blood loss,¹³ lower postoperative pain14, shorter hospitalization stays¹⁵ and decreased complication rates.^16,17 In view of the reduced exposure-related morbidity associated with MIS-TLIF, some authors have suggested that this procedure may be particularly beneficial for elderly patients in whom increased blood loss, slower perioperative mobilization, and delayed wound healing could have more profound implications.^4,18,19

Although some studies have suggested that MIS-TLIF is associated with fewer perioperative complications in elderly patients, there are fewer comparative studies assessing the functional outcomes and quality of life of elderly patients undergoing this procedure.^20-25 A recent meta-analysis conducted by Huang et al found 12 studies comparing the complications and functional outcomes after MIS-TLIF in the elderly.²⁶ However, the study with the longest follow-up referenced by Huang et al was at 3 years, and the outcomes of MIS-TLIF in the elderly have not yet been evaluated at 5-year follow-up.

The purpose of this study was to compare the clinical and radiological outcomes of MIS-TLIF in elderly patients and younger controls at a minimum follow-up of 5 years.

Methods

This study received ethical board approval from the SingHealth Centralised Institutional Review Board (Approval Number: 2020/2311). Informed consent was obtained from all patients in the study. We reviewed all patients who underwent primary, single-level MIS-TLIF for grade 1 or 2 degenerative spondylolisthesis between 2012 and 2014. Patients who underwent spinal fusion for tumor, trauma or infection were excluded. Data was prospectively collected and stored in an institutional spine registry. During the study period, 168 consecutive patients met the inclusion criteria, of which 39 patients were ≥70 years old (“elderly group”) and 129 patients were <70 years old (“control group”). All younger patients completed follow-up, whereas 9 elderly patients had passed away before 5 years (six from cardiorespiratory causes, two from malignancy, one from cerebrovascular accident), leaving 30 elderly patients available for analysis. These patients were propensity score matched in a 1:3 ratio with patients aged less than 70 years to minimize selection bias and control for potential confounders. Covariates included in the matching algorithm were sex, body mass index (BMI), American Society of Anesthesiologists (ASA) class, comorbidities and baseline patient-reported outcome measures (PROMs).

All procedures were performed by three fellowship-trained spine surgeons. First, the operative level was confirmed using a mobile C-arm X-ray. The surgical incision was then made 3-5 cm parallel to midline on the symptomatic side. Tissue dilators were inserted down to the facet complex. Facetectomy was subsequently performed to visualize the posterolateral part of the intervertebral disc, followed by discectomy and preparation of the endplates. Intradiscal spreaders were used to distract the disc space and local autogenous bone, combined with allograft bone was placed anterior and contralateral to the annulotomy along with an appropriately sized interbody cage filled with bone graft. The positioning of the cage was confirmed using fluoroscopy. To ensure decompression, the remainder of the ipsilateral facet and lamina was resected and the lateral margin of the ligamentum flavum was removed to expose the ipsilateral exiting and transversing nerve roots. In the presence of bilateral disease, the patient was tilted and the tubular retractor angled medially to visualize the contralateral side. This was followed by an over-the-top decompression where indicated. After decompression, percutaneous pedicle screws and rod was inserted via the same incision followed by a second contralateral incision with a similar percutaneously placed construct. Compression was applied across the construct to restore lordosis before final locking. Meticulous hemostasis and wound irrigation were performed prior to closure.

Patients undergoing elective spine surgery at our institution embarked on a standardized perioperative pathway. Preoperatively, patients underwent an evaluation for their physical capacity, medical fitness for surgery, cognitive ability, pain control, and nutritional status. They also received a standardized preoperative education package. On the day of surgery, patients received standard antibiotic prophylaxis using cefazolin or vancomycin (if allergic to cephalosporins), multimodal analgesia, antifibrinolytics, goal-directed fluid therapy and transfusions. Postoperatively, all patients received a standardized pain regimen, bowel regimen, early oral fluid and food intake, early rehabilitation and mobilization, early intravenous fluids discontinuation, standardized urinary catheter management, and discharge criteria. Multimodal analgesia included PO and IV acetaminophen, duloxetine or gabapentin and IV opioids according to the discretion of the anesthesiologist. A regular diet was given in recovery room, when possible, on postoperative day (POD) 0. Intravenous fluids were discontinued the morning of POD 1. The urinary catheter (if placed) was removed within 24 hours after surgery. Surgical drains (if placed) were generally removed within 48 hours after surgery. Early mobilization included on-bed movement on the day of surgery, all meals in a chair starting POD 0, as well as sitting and assisted walking on POD 1.

The primary endpoints of the study were PROMs such as the Oswestry Disability Index (ODI), 36-Item Short-Form Physical Component Summary (SF-36 PCS), Mental Component Summary (SF-36 MCS), Visual Analogue Scale (VAS) for back pain, and VAS for leg pain. PROMs were compared at 6 months, 2 years and 5 years. Clinical improvement was defined using the minimal clinically important difference (MCID), which represents a change in score that is considered meaningful to the patient. Published values of 12.8 for ODI, 1.2 for back pain, 1.6 for leg pain, and 4.9 for SF-36 PCS²⁷ were used to determine whether or not the MCID was achieved. The published value of 15.3 for ODI²⁸ was used to determine whether the patient acceptable symptom state (PASS) was achieved. Patient satisfaction and expectation fulfilment were assessed using the North American Spine Society (NASS) questionnaire.²⁹

Secondary outcomes such as perioperative complications, length of stay and 90-day readmissions were recorded. Radiographic fusion was assessed at 2 years and at final follow-up using the grading system of Bridwell et al³⁰ Radiographic adjacent-segment degeneration (ASD) was determined by comparing radiographs taken preoperatively and at last follow-up, irrespective of clinical symptoms. The following degenerative changes were identified: anterolisthesis or retrolisthesis of more than 3 mm, a decrease in the adjacent-segment disc height of more than 3 mm, or an intervertebral angle of flexion greater than 5°.^31,32 Details on any revision procedure were recorded. The mean follow-up was 7.2 ± 2.0 years.

A power analysis was performed prior to the study. To detect an MCID of 12.8 points on the ODI with a standard deviation of 15, a sample size of at least 23 patients in each group would be required to achieve a power of .80.²⁷ These calculations were done for a two-sided test with an alpha of .05. Patient characteristics and clinical outcomes were compared between the groups using a chi-square test for categorical variables and independent t-test for continuous variables. Statistical analyses were performed using the SPSS software package, version 20.0 (SPSS Inc, Chicago, IL). Statistical significance was defined as P < .05.

Results

There were 30 elderly patients and 90 controls included in the study. The two groups were well matched for sex, BMI, ASA score and comorbidity burden (Table 1). There was no difference in operative time between the groups. Elderly patients had a longer length of stay (4.7 ± 5.8 days vs 3.3 ± 1.4 days, P = .035) and more readmissions (10.0% vs 1.1%, P = .019). However, there was no difference in transfusions, complication rates or discharge disposition (Table 2). Three medical complications occurred in the control group: one patient had sick sinus syndrome, one had severe postoperative vomiting, and the third patient had a gout flare of the knee joint. One elderly patient had cellulitis following a flare of bullous pemphigoid. There were no surgery-related complications encountered.

Table 1.

Baseline Characteristics by Age Group After Propensity Score Matching.

	Control (N = 90)	Elderly (N = 30)	^aP-value^b
Age (mean ± SD, years)	58.3 ± 7.1	73.5 ± 3.4	<.001
Sex % (n)			.688
Female	80.0% (72)	83.3% (25)
Male	20.0% (18)	16.7% (5)
BMI (mean ± SD, kg/m²)	25.5 ± 3.8	24.8 ± 3.4	.309
ASA (mean ± SD)	2.1 ± 0.4	2.2 ± 0.5	.293
Comorbidities (mean ± SD)	1.4 ± 1.2	1.8 ± 1.4	.115
Diabetes % (n)	16.7% (15)	20.0% (6)
Hypertension % (n)	50.0% (45)	66.7% (20)
Hyperlipidemia % (n)	44.4% (40)	43.3% (13)
Ischemic heart disease % (n)	4.4% (4)	16.7% (5)
Kidney disease % (n)	0% (0)	0% (0)
Stroke % (n)	1.1% (1)	0% (0)
Peripheral vascular disease % (n)	0% (0)	0% (0)
Asthma % (n)	3.3% (3)	0% (0)
Osteoarthritis % (n)	14.4% (13)	23.3% (7)
Depression % (n)	1.1% (1)	3.3% (1)
No comorbidities % (n)	23.3% (21)	23.3% (7)

BMI: body mass index; ASA: American society of anesthesiologists class.

^aP-value was calculated for each category using chi square analysis (categorical) or student’s t-test (continuous).

^bBoldface indicates statistical significance.

Table 2.

Perioperative Characteristics by Age Group.

	Control (N = 90)	Elderly (N = 30)	^aP-value^b
Diagnosis % (n)
Degenerative spondylolisthesis	100 (90)	100 (30)	1.000
Number of levels % (n)
1-Level	100 (90)	100 (30)	1.000
Operative time (mean ± SD, min)	162.9 ± 44.8	151.2 ± 39.0	.208
Blood transfusions % (n)	0 (0)	0 (0)	—
Complications % (n)			1.000
Minor	3.3 (3)	3.3 (1)
Major	0 (0)	0 (0)
Length of stay (mean ± SD, days)	3.3 ± 1.4	4.7 ± 5.8	.035
Discharge to rehabilitation % (n)	0 (0)	3.3% (1)	.082
Readmissions % (n)	1.1% (1)	10.0% (3)	.019

^aP-value was calculated for each category using chi square analysis (categorical) or student’s t-test (continuous).

^bBoldface indicates statistical significance.

When analyzing PROMs, elderly patients had better VAS leg pain than controls at 2 years (P = .037), although this did not exceed the MCID of 1.6 points. In contrast, there was no difference in ODI, VAS back pain, VAS leg pain, SF-36 PCS and SF-36 MCS at 5 years (Table 3). The percentage of patients that achieved the MCID for each PROM was also similar between the groups (Table 4). The percentage of patients that achieved the PASS for ODI was 80.0% in the elderly group and 71.1% in the control group (P = .340). An analysis of subjective outcomes revealed that 93.3% of elderly patients and 91.1% of controls were satisfied at 5 years (P = .703), whereas 93.3% and 90.0% had their expectations fulfilled, respectively (P = .584).

Table 3.

Patient-Reported Outcomes by Age Group.

	Control (N = 90)	Elderly (N = 30)	^aP-value^b
VAS back (mean ± SD)
Preoperative	6.0 ± 2.8	5.6 ± 2.3	.416
6-month	1.9 ± 2.5	1.5 ± 2.4	.361
2-year	1.3 ± 2.2	1.1 ± 2.3	.656
5-year	1.1 ± 2.2	.8 ± 2.1	.503
VAS leg (mean ± SD)
Preoperative	6.4 ± 2.9	6.5 ± 2.9	.788
6-month	1.2 ± 2.2	.5 ± 1.7	.119
2-year	.9 ± 2.0	.1 ± 0.7	.037
5-year	.5 ± 1.6	.0 ± 0.6	.101
ODI (mean ± SD)
Preoperative	48.6 ± 16.9	49.8 ± 15.8	.717
6-month	18.1 ± 14.1	20.5 ± 14.1	.423
2-year	14.5 ± 16.2	16.8 ± 15.1	.494
5-year	11.9 ± 13.7	11.9 ± 11.4	.977
SF-36 PCS (mean ± SD)
Preoperative	31.8 ± 8.5	31.4 ± 9.0	.833
6-month	45.0 ± 11.1	43.2 ± 11.0	.430
2-year	48.5 ± 10.2	44.6 ± 12.3	.092
5-year	48.5 ± 9.7	44.5 ± 9.7	.052
SF-36 MCS (mean ± SD)
Preoperative	49.0 ± 10.4	50.8 ± 10.8	.416
6-month	52.3 ± 11.7	53.1 ± 8.8	.752
2-year	53.3 ± 10.5	54.0 ± 10.3	.733
5-year	52.8 ± 11.0	52.9 ± 11.9	.954

VAS: visual analogue scale; ODI: oswestry disability index; SF-36 PCS: short form-36 physical component score; SF-36 MCS: short form-36 mental component score.

^aP-value was calculated for each category using student’s t-test.

^bBoldface indicates statistical significance.

Table 4.

Achievement of Minimal Clinically Important Difference and Satisfaction at 5 Years.

	Control (N = 90)	Elderly (N = 30)	^aP-value^b
MCID for VAS back % (n)	80.0% (72)	80.0% (24)	1.000
MCID for VAS leg % (n)	82.2% (74)	90.0% (27)	.312
MCID for ODI % (n)	85.6% (77)	90.0% (27)	.535
MCID for SF-36 PCS % (n)	83.3% (75)	66.7% (20)	.052
PASS for ODI % (n)	71.1% (64)	80.0% (24)	.340
Satisfaction % (n)	91.1% (82)	93.3% (28)	.703
Expectation fulfilment % (n)	90.0% (81)	93.3% (28)	.584

VAS: visual analogue scale; ODI: oswestry disability index; SF-36 PCS: short form-36 physical component score.

^aP-value was calculated for each category using chi square analysis.

^bBoldface indicates statistical significance.

Radiographic fusion at the 2-year mark was 60.0% and 64.4% in the elderly and control groups, respectively (P = .669). At final follow-up of 7.2 ± 2.0 years, there was also no difference in fusion rates, with 96.7% of elderly patients and 94.4% of controls achieving radiographic fusion (P = .605). A total of 33.3% and 40.0% were found to have radiological ASD, respectively (P = .503). There were 3 revisions (3.3%) in the control group (2 for symptomatic ASD, 1 for screw loosening), but no revisions in the elderly group (P = .311).

Discussion

As life expectancies increase, the number of elderly patients requiring surgical intervention for degenerative spinal conditions will continue to rise.³³ Technological improvements coupled with the growing desire for an improved quality of life have resulted in an increase in the number of spinal procedures performed in elderly patients. Given that MIS spine surgery can reduce soft tissue disruption and expedite functional recovery,^{4,10,18,19,34} these procedures have been theorized to be beneficial for elderly patients in whom operative morbidity and delayed mobility may have profound consequences.^18,19 However, few studies have analyzed the long-term outcomes of MIS-TLIF in this growing subpopulation. The present study found that elderly patients who underwent MIS-TLIF not only had similar perioperative outcomes, but also experienced comparable improvements in pain, disability and quality of life that were sustained for up to 5 years with no long-term deterioration.

Multiple non-comparative studies have examined the perioperative complications in an elderly population, albeit using heterogenous cohorts that included many different spine procedures.^5-8 Ragab et al studied a group of 118 patients aged ≥70 years who underwent single- and multi-level laminectomies with or without posterolateral fusion, reporting a complication rate of 20%.⁵ This rate was comparable to that reported by Deyo et al, who examined the hospital discharge registry of Washington state and found a morbidity rate of 18% in lumbar spine surgery patients aged 75 years or older.⁶ Large database studies have also evaluated the rate of major complications in octogenarians undergoing lumbar fusion, albeit with contrasting findings.^7,8 Despite the growing interest in MIS spine surgery over the past decade, there has been scant literature available in regards to the outcomes of MIS-TLIF in elderly patients with degenerative spinal disorders.^19,35,36 Lee et al found that 35 patients aged ≥65 years undergoing single-level MIS-TLIF had a similar overall complication rate as patients aged <65 years (20% vs 16%).³⁵ However, elderly patients had longer hospital stays (3.89 days vs 2.49 days, P = .0071) and were more frequently discharged to subacute nursing facilities or inpatient rehabilitation centers (17.1% vs 0%,). In the same vein, Karikari et al analyzed the results of MIS-TLIF and extreme lateral interbody fusion in 66 patients aged ≥70 years and reported an overall low rate of major complications (7.4%).¹⁹ Nikhil et al also compared 2-year outcomes of MIS-TLIF in 22 patients >75 years old with that of aged 50.0-64.9 and 65.0-74.9 years, and concluded that older patients could obtain comparable outcomes without increased complication risks.³⁷ The present study found similar results as previous studies, as we did not find any difference in operative time, transfusions, complications or discharge disposition between the elderly and control groups, despite a higher 90-day readmission rate in older patients (10% vs 1%). In addition to one minor medical complication that occurred unrelated to spine surgery, the two additional readmissions in the elderly group were due to a slower rehabilitation course at home and resultant disposition issues. The current findings add to the growing body of literature supporting low perioperative morbidity associated with MIS-TLIF, which could be particularly beneficial in elderly patients with degenerative spine disease.

In addition to traditional endpoints such as perioperative complications and readmission rates, this study sought to evaluate the long-term PROMs of MIS-TLIF in an elderly population, as these outcome measures integrate a subjective, patient-centered assessment of ‘value’ that cannot be measured using traditional 90-day outcomes. Using propensity score matching to ensure baseline comparability in demographics, comorbidities and functional status, we found that older patients experienced similar improvements in pain, disability and health-related quality of life, ultimately achieving PROMs that were no different from that of younger controls at 5-year follow-up. To quantify the degree of clinical benefit following MIS-TLIF and standardize the comparison of outcome scores, the concept of MCID was also applied. Importantly, the proportion of patients that achieved the MCID for each PROM was also similar between the groups. Furthermore, we administered the NASS questionnaire and found that 93% of elderly patients as well as 91% of controls were satisfied with their treatment at 5 years, which was similar to published rates at a shorter follow-up.^5,25 The current study not only reinforces previous literature that has shown comparable 2-year outcomes of MIS-TLIF in an elderly population,²⁵ but also add to the literature by demonstrating the long-term durability of these clinical improvements at 5 years.

Stable fusion following lumbar spinal instrumentation is an important consideration, especially for elderly patients who may experience an age-related decline in biological processes involved in bone healing.³⁸ Noncomparative studies noted stable fusion in the majority of elderly patients undergoing posterolateral fusion.^39-41 Costa et al reported a 79% fusion rate following posterolateral fusion in 53 patients aged >75 years at 18 months follow-up,³⁹ while Wu et al reported a 76% fusion rate in 82 patients aged ≥65 years at minimum 2 years follow-up.⁴⁰ In contrast, a comparison by Okuda et al noted a higher incidence of delayed union in 31 elderly patients (≥70 years) undergoing posterior lumbar interbody fusion compared to those younger controls,⁴² and Liao et al reported a higher incidence of nonunion and new osteoporotic fractures in 38 octogenarians undergoing posterolateral fusion.⁴³ The present findings were more similar to that of Jo et al, who reported comparable fusion rates in patients ≥65 and <65 years (92% vs 95%) undergoing open TLIF.⁴⁴ At mean 7.2 years, 96.7% of elderly patients achieved stable fusion compared to 94.4% of controls.

As the demand of lumbar fusions continue to grow annually, ASD is another important concern. The reported incidence of ASD following lumbar fusion may varies substantially, with one recent meta-analysis of 94 studies reporting an incidence of 5%-77%.⁴⁵ A separate systematic review reported the risk of radiologic ASD to be 8%-100% over a follow-up duration of 36-369 months.⁴⁶ Previous studies have suggested a lower risk of ASD in patients younger <60 years of age,^46,47 postulating that older patients were more susceptible to degenerative changes and increased mechanical stress in the adjacent segments.^37,48 In the present study, however, the rate of radiological ASD at long-term follow-up of 7.2 years was 33% in the elderly group and 40% in the control group, which was not statistically different. Moreover, symptomatic ASD was observed in 2 controls that required revision surgery. It is encouraging to note that most ASD cases were not symptomatic––a finding that was echoed by Zhong et al, who demonstrated that at 27 months, only 11.7% of lumbar fusion patients developed symptomatic ASD.⁴⁹ Similar to our study, Liao et al noted that three controls and no octogenarians developed ASD following instrumented lumbar arthrodesis at minimum 2-year follow-up.⁵⁰ It is possible that a decreased activity level in elderly patients may account for the decreased the incidence of ASD. Furthermore, Overall, these findings question the assertion that advanced age is a risk factor for ASD, although larger prospective studies are needed to validate the long-term success of MIS-TLIF in the elderly population.

This study has several limitations. This was a retrospective, nonrandomized study. It is possible that selection bias could have been introduced if only elderly patients deemed fit to proceed by the attending surgeon were included in the study cohort. However, outcome measures were prospectively collected according to an established protocol and stored in an institutional spine registry, likely addressing any bias in data collection. Furthermore, we attempted to reduce bias using propensity score matching to control for possible confounding factors, such as sex, BMI, ASA score and baseline PROMs, thus ensuring a degree of homogeneity. Nonetheless, certain variables such as the degree of canal or foraminal stenosis as well as the extent of decompression could not be controlled for and may have affected our results. Potential differences in preoperative bone density could have also confounded the influence of age on the quality of bony fusion following MIS-TLIF. In addition, the fact that MIS-TLIF was performed by a small number of surgeons with over two decades of experience in MIS spine surgery could have biased upward the results, hence reducing generalizability. Further, although the study had sufficient statistical power for the primary endpoints (ie PROMs), the small sample size may limit the conclusions that can be drawn with regards to secondary endpoints such as complication and readmission rates. Last, we did not delineate very elderly patients ≥80 years old from elderly patients as there were only four such patients in the cohort; therefore, it is possible that patients in their ninth decade may have poorer outcomes. Further studies on this subgroup of very elderly patients are warranted.

Conclusion

As the population ages, physicians will encounter more elderly patients who have the desire to maximize their mobility and independence. Traditional assumptions about their expectations should be revisited in light of recent technological advancements that have the potential to improve their quality of life while maintaining high safety standards. Elderly patients undergoing MIS surgery not only had comparable perioperative complication rates to that of younger patients, but also experienced a clinically meaningful improvement in pain, function, and quality of life after MIS-TLIF. These results were sustained for 5 years with no longer-term deterioration, and a high rate of satisfaction and expectation fulfilment was achieved.

Footnotes

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

IRB

Centralised institutional review board (IRB) approval (CIRB 2020/2311) was obtained.

ORCID iDs

Graham S. Goh

Reuben Chee Cheong Soh

References

Weinstein

Lurie

Tosteson

et al. Surgical versus nonsurgical treatment for lumbar degenerative spondylolisthesis. N Engl J Med. 2007;356:2257-2270. doi:10.1056/nejmoa070302.

Weinstein

Tosteson

Lurie

SPORT Investigators , et al. Surgical versus nonsurgical therapy for lumbar spinal stenosis. N Engl J Med. 2008;358:794-810. doi:10.1056/nejmoa0707136.

Goh

Tay

YWA

Yue

W-M

Guo

C-M

Tan

S-B

Chen

JL-T

. What are the patient-reported outcomes, complications, and radiographic results of lumbar fusion for degenerative spondylolisthesis in patients younger than 50 years? Clin Orthop. 2020;478:1880-1888. doi:10.1097/CORR.0000000000001252.

Rosen

O’Toole

Eichholz

, et al. Minimally invasive lumbar spinal decompression in the elderly. Neurosurgery. 2007;60:503-510. doi:10.1227/01.neu.0000255332.87909.58.

Ragab

Fye

Bohlman

. Surgery of the lumbar spine for spinal stenosis in 118 patients 70 years of age or older. Spine. 2003;28:348-353. doi:10.1097/01.BRS.0000048494.66599.

Deyo

Cherkin

Loeser

Bigos

Ciol

. Morbidity and mortality in association with operations on the lumbar spine. The influence of age, diagnosis, and procedure. J Bone Joint Surg Am. 1992;74:536-543.

Puvanesarajah

Jain

Shimer

, et al. Complications and mortality following 1 to 2 level lumbar fusion surgery in patients above 80 years of age. Spine. 2017;42:437-441. doi:10.1097/brs.0000000000001759.

Lieber

Chiang

Prabhu

, et al. Postoperative complications for elderly patients after single-level lumbar fusions for spondylolisthesis. World Neurosurg. 2016;91:149-153. doi:10.1016/j.wneu.2016.03.052.

Deyo

Ciol

Cherkin

Loeser

Bigos

. Lumbar spinal fusion. A cohort study of complications, reoperations, and resource use in the Medicare population. Spine. 1993;18:1463-1470. doi:10.1097/00007632-199309010-00010.

10.

Peng

CWB

Yue

Poh

Yeo

Tan

. Clinical and radiological outcomes of minimally invasive versus open transforaminal lumbar interbody fusion. Spine. 2009;34:1385-1389. doi:10.1097/brs.0b013e3181a4e3be.

11.

Goldstein

Macwan

Sundararajan

Rampersaud

. Comparative outcomes of minimally invasive surgery for posterior lumbar fusion: A systematic review. Clin Orthop Relat Res. 2014;472:1727-1737. doi:10.1007/s11999-014-3465-5.

12.

Sidhu

Henkelman

Vaccaro

, et al. Minimally invasive versus open posterior lumbar interbody fusion: A systematic review. Clin Orthop Relat Res. 2014;472:1792-1799. doi:10.1007/s11999-014-3619-5.

13.

Rahman

Summers

Richter

Mimran

Jacob

. Comparison of techniques for decompressive lumbar laminectomy: The minimally invasive versus the “classic” open approach. Minim Invasive Neurosurg. 2008;51:100-105. doi:10.1055/s-2007-1022542.

14.

Podichetty

Spears

Isaacs

Booher

Biscup

. Complications associated with minimally invasive decompression for lumbar spinal stenosis. J Spinal Disord Tech. 2006;19:161-166. doi:10.1097/01.bsd.0000188663.46391.73.

15.

Mobbs

Sivabalan

Raley

Rao

. Outcomes after decompressive laminectomy for lumbar spinal stenosis: Comparison between minimally invasive unilateral laminectomy for bilateral decompression and open laminectomy: Clinical article. J Neurosurg Spine. 2014;21:179-186. doi:10.3171/2014.4.spine13420.

16.

Tang

Zhang

. Minimally invasive versus open transforaminal lumbar fusion: A systematic review of complications. Int Orthop. 2016;40:1883-1890. doi:10.1007/s00264-016-3153-z.

17.

Goldstein

Macwan

Sundararajan

Rampersaud

. Perioperative outcomes and adverse events of minimally invasive versus open posterior lumbar fusion: Meta-analysis and systematic review. J Neurosurg Spine. 2016;24:416-427. doi:10.3171/2015.2.spine14973.

18.

Karikari

Isaacs

. Minimally invasive transforaminal lumbar interbody fusion: A review of techniques and outcomes. Spine. 2010;35:S294-S301. doi:10.1097/brs.0b013e3182022ddc.

19.

Karikari

Grossi

Nimjee

, et al. Minimally invasive lumbar interbody fusion in patients older than 70 years of age: Analysis of peri- and postoperative complications. Neurosurgery. 2011;68:897-902. doi:10.1227/neu.0b013e3182098bfa.

20.

Aleem

Rampersaud

. Elderly patients have similar outcomes compared to younger patients after minimally invasive surgery for spinal stenosis. Clin Orthop Relat Res. 2014;472:1824-1830. doi:10.1007/s11999-013-3411-y.

21.

Carreon

Puno

Dimar

Glassman

Johnson

. Perioperative complications of posterior lumbar decompression and arthrodesis in older adults. J Bone Jt Surg-Am. 2003;85:2089-2092. doi:10.2106/00004623-200311000-00004.

22.

Fujita

Kostuik

Huckell

Sieber

. Complications of spinal fusion in adult patients more than 60 years of age. Orthop Clin N Am. 1998;29:669-678. doi:10.1016/s0030-5898(05)70040-7.

23.

Raffo

Lauerman

. Predicting morbidity and mortality of lumbar spine arthrodesis in patients in their ninth decade. Spine. 2006;31:99-103. doi:10.1097/01.brs.0000192678.25586.e5.

24.

Vitaz

Raque

Shields

Glassman

. Surgical treatment of lumbar spinal stenosis in patients older than 75 years of age. J Neurosurg. 1999;91:181-185. doi:10.3171/spi.1999.91.2.0181.

25.

Goh

GS-H

Tay

YWA

Liow

MHL

, et al. Elderly patients undergoing minimally invasive transforaminal lumbar interbody fusion may have similar clinical outcomes, perioperative complications, and fusion rates as their younger counterparts. Clin Orthop. 2020;478:822-832. doi:10.1097/CORR.0000000000001054.

26.

Huang

Rabin

Stricsek

Swong

. Outcomes and complications of minimally invasive transforaminal lumbar interbody fusion in the elderly: A systematic review and meta-analysis. J Neurosurg Spine. 2022;36:741-752. doi:10.3171/2021.7.SPINE21829.

27.

Copay

Glassman

Subach

Berven

Schuler

Carreon

. Minimum clinically important difference in lumbar spine surgery patients: A choice of methods using the oswestry disability index, medical outcomes study questionnaire short form 36, and pain scales. Spine J. 2008;8:968-974. doi:10.1016/j.spinee.2007.11.006.

28.

Goh

Soh

RCC

Yue

W-M

Guo

C-M

Tan

S-B

Chen

JL-T

. The patient acceptable symptom state for the oswestry disability index following single-level lumbar fusion for degenerative spondylolisthesis. Spine J. 2020:12(4).

29.

Daltroy

Cats-Baril

Katz

Fossel

Liang

. The North American spine society lumbar spine outcome assessment instrument. Spine. 1996;21:741-748. doi:10.1097/00007632-199603150-00017.

30.

Bridwell

Lenke

McEnery

Baldus

Blanke

. Anterior fresh frozen structural allografts in the thoracic and lumbar spine. Spine. 1995;20:1410-1418. doi:10.1097/00007632-199520120-00014.

31.

Okuda

Nagamoto

Matsumoto

Sugiura

Takahashi

Iwasaki

. Adjacent segment disease after single segment posterior lumbar interbody fusion for degenerative spondylolisthesis. Spine. 2018;43:E1384-E1388. doi:10.1097/brs.0000000000002710.

32.

Yamasaki

Hoshino

Omori

, et al. Risk factors of adjacent segment disease after transforaminal inter-body fusion for degenerative lumbar disease. Spine. 2017;42:E86-E92. doi:10.1097/brs.0000000000001728.

33.

Deyo

Gray

Kreuter

Mirza

Martin

. United States trends in lumbar fusion surgery for degenerative conditions. Spine. 2005;30:1441-1445. doi:10.1097/01.brs.0000166503.37969.8a.

34.

Lauryssen

. Technical advances in minimally invasive surgery: Direct decompression for lumbar spinal stenosis. Spine. 2010;35:S287-S293. doi:10.1097/brs.0b013e3182023268.

35.

Lee

Fessler

. Perioperative and postoperative complications of single-level minimally invasive transforaminal lumbar interbody fusion in elderly adults. J Clin Neurosci. 2012;19:111-114. doi:10.1016/j.jocn.2011.09.005.

36.

Rodgers

Gerber

Rodgers

. Lumbar fusion in octogenarians: The promise of minimally invasive surgery. Spine. 2010;35:S355-S360. doi:10.1097/BRS.0b013e3182023796.

37.

Nikhil N

Lim

JW-A

Yeo

Yue

W-M

. Elderly patients achieving clinical and radiological outcomes comparable with those of younger patients following minimally invasive transforaminal lumbar interbody fusion. Asian Spine J. 2017;11:230-242. doi:10.4184/asj.2017.11.2.230.

38.

Clark

Nakamura

Miclau

Marcucio

. Effects of aging on fracture healing. Curr Osteoporos Rep. 2017;15:601-608. doi:10.1007/s11914-017-0413-9.

39.

Costa

Ortolina

Tomei

Cardia

Zekay

Fornari

. Instrumented fusion surgery in elderly patients (over 75 years old): Clinical and radiological results in a series of 53 patients. Eur Spine J. 2013;22(Suppl 6):910-913. doi:10.1007/s00586-013-3021-0.

40.

C-H

Kao

Y-H

Yang

S-C

T-S

Lai

P-L

Chen

W-J

. Supplementary pedicle screw fixation in spinal fusion for degenerative spondylolisthesis in patients aged 65 and over: Outcome after a minimum of 2 years follow-up in 82 patients. Acta Orthop. 2008;79:67-73. doi:10.1080/17453670710014789.

41.

Tokuhashi

Ajiro

Umezawa

. Outcomes of posterior fusion using pedicle screw fixation in patients >or=70 years with lumbar spinal canal stenosis. Orthopedics. 2008;31:1096.

42.

Okuda

Oda

Miyauchi

Haku

Yamamoto

Iwasaki

. Surgical outcomes of posterior lumbar interbody fusion in elderly patients. Surgical technique. J Bone Jt Surg-Am. 2007;89:310-320. doi:10.2106/00004623-200709001-00013.

43.

Liao

J-C

Chiu

P-Y

Chen

W-J

Chen

L-H

Niu

C-C

. Surgical outcomes after instrumented lumbar surgery in patients of eighty years of age and older. BMC Muscoskel Disord. 2016;17:402. doi:10.1186/s12891-016-1239-9.

44.

D-J

Jun

J-K

Kim

K-T

Kim

S-M

. Lumbar interbody fusion outcomes in degenerative lumbar disease: Comparison of results between patients over and under 65 years of age. J Korean Neurosurg Soc. 2010;48:412-418. doi:10.3340/jkns.2010.48.5.412.

45.

Xia

X-P

Chen

H-L

Cheng

H-B

. Prevalence of adjacent segment degeneration after spine surgery: A systematic review and meta-analysis. Spine. 2013;38:597-608. doi:10.1097/BRS.0b013e318273a2ea.

46.

Park

Garton

Gala

Hoff

McGillicuddy

. Adjacent segment disease after lumbar or lumbosacral fusion: Review of the literature. Spine. 2004;29:1938-1944. doi:10.1097/01.brs.0000137069.88904.03.

47.

Lawrence

Wang

Arnold

Hermsmeyer

Norvell

Brodke

. Predicting the risk of adjacent segment pathology after lumbar fusion: A systematic review. Spine. 2012;37:S123-S132. doi:10.1097/BRS.0b013e31826d60d8.

48.

Cheh

Bridwell

Lenke

, et al. Adjacent segment disease followinglumbar/thoracolumbar fusion with pedicle screw instrumentation: A minimum 5-year follow-up. Spine. 2007;32:2253-2257. doi:10.1097/BRS.0b013e31814b2d8e.

49.

Zhong

Z-M

Deviren

Tay

Burch

Berven

. Adjacent segment disease after instrumented fusion for adult lumbar spondylolisthesis: Incidence and risk factors. Clin Neurol Neurosurg. 2017;156:29-34. doi:10.1016/j.clineuro.2017.02.020.

50.

Liao

J-C

Chen

W-J

. Surgical outcomes in the elderly with degenerative spondylolisthesis: Comparative study between patients over 80 years of age and under 80 years—a gender-diagnosis-and surgical method-matched two-cohort analyses. Spine J. 2018;18:734-739. doi:10.1016/j.spinee.2017.08.250.