Comparative analysis of surgically treated degenerative cervical and lumbar spine diseases using multiple clinical aging indices

Abstract

Background

The prevalence of degenerative spine diseases has continued to rise with the aging of the global population. Despite the availability of various aging indices, limited studies have comprehensively investigated degenerative spine diseases from the perspective of aging. This study aimed to evaluate degenerative cervical and lumbar diseases surgically treated using multiple clinical aging indices and elucidate the characteristics of each condition through comparative analysis.

Methods

Clinical data of consecutive patients aged ≥ 65 years who underwent surgery for degenerative cervical and lumbar diseases were retrospectively collected. Frailty was assessed using the 11-point modified frailty index. Locomotive syndrome stage was determined based on the 25-Question Geriatric Locomotive Function Scale. Functional decline was assessed according to the Kihon Checklist. Polypharmacy was defined based on a cutoff of six drugs. A total of 19 categories were considered potentially inappropriate medications.

Results

Among the included patients, 313 and 103 had degenerative lumbar (L group) and degenerative cervical (C group) diseases, respectively. The C group had significantly lower serum albumin levels (p = 0.03), a significantly higher frequency of functional decline in both physical function (p = 0.02) and activities of daily living (p = 0.046), and significantly more advanced frailty (p = 0.004) than the L group. Among potentially inappropriate medications, the frequency of diuretic use was significantly higher in the C group than in the L group (p = 0.04). Longitudinal observations showed significant postoperative improvements in locomotive syndrome stages in the L group but not the C group. Cross-sectional observations revealed no significant differences in locomotive syndrome stage distributions between both the groups before surgery (p = 0.402); however, the C group exhibited significantly more advanced locomotive syndrome stages than the L group at 6 months (p < 0.001) and 1 year after surgery (p < 0.001).

Conclusions

Across various indices of aging, patients with degenerative cervical spine disease showed more significant progression than those with lumbar spine disease. Thorough understanding of these characteristics is essential when managing degenerative spine diseases, particularly in the selection of effective treatment approaches for the increasingly aging society in the future.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-025-09185-8.

Background

With the aging of the global population, the prevalence of degenerative spine diseases has continued to rise [1–3]. These conditions are often accompanied by severe pain and numbness and frequently cause neurological complications, which significantly impair activities of daily living (ADLs) [4–7]. Degenerative spine diseases, which commonly affect lower extremity function, reduces mobility and increases the risk of falls, thereby shortening the healthy life expectancy of the older adults [4, 8, 9]. Among the identified degenerative spine diseases, lumbar spinal stenosis and cervical spondylotic myelopathy have been the most common indications for surgery in the lumbar and cervical spine, respectively. The former is characterized by intermittent claudication, which considerably limits walking distance [5, 6], whereas the latter often presents with a spastic gait when involving the lower extremities, which markedly increases the risk of falls [4]. Both conditions frequently occur among older adults, making their effective management a critical issue in aging societies.

Frailty and sarcopenia are commonly used as clinical indices of aging among older adults [10]. However, various tools have been used for frailty assessments, with the modified frailty index (mFI) commonly employed for preoperative risk evaluation [11]. Evidence suggests that the 11-point mFI, which examines 11 factors derived from the patient’s condition, is the most established tool, though the 5-point mFI-5 has also been increasingly used [12]. Additionally, the concept of locomotive syndrome, focusing on decreased mobility in older adults, has also been utilized as a clinical index of aging [13]. Locomotive syndrome has conventionally been assessed using a stand-up test, a two-step test, and the 25-Question Geriatric Locomotive Function Scale (GLFS-25) [13]. Recent reports have suggested that the results of these three tests generally align with those of the GLFS-25 alone [14, 15]. From a pharmacological perspective, the presence of polypharmacy and the use of potentially inappropriate medications (PIMs) are important indicators given their potential to cause adverse drug events among older adults [16, 17]. Thus, despite the availability of various aging indices, no studies have comprehensively examined degenerative spine diseases from the perspective of aging. Moreover, research comparing cervical spine and lumbar spine diseases using these aging indices have been sorely lacking. Clarifying the characteristics of these conditions from an aging perspective would undoubtedly contribute to their effective management. Hence, the current study aimed to evaluate degenerative cervical and lumbar spine diseases using various clinical aging indices and elucidate the characteristics of each condition through comparative analysis.

Methods

Subjects

Clinical data of consecutive patients aged ≥ 65 years who underwent surgery for degenerative cervical and lumbar spine diseases at a single acute care hospital between April 2020 and May 2023 were retrospectively collected. Those who underwent surgery for spinal deformity and ossification of posterior longitudinal ligament (OPLL) were excluded (Fig. 1).

Fig. 1.

Flowchart of this study

Ethics approval and consent to participate

This study was approved by the institutional ethics committee. Informed consent was obtained through the opt-out method. All study methods were conducted in accordance with the principles stated in the Declaration of Helsinki.

Data acquisition

The following data were retrieved for analysis: age; body mass index (BMI); sex; medical history (e.g., hypertension, dyslipidemia, diabetes, stroke, cardiovascular disease, and cancer); preoperatively prescribed drugs; preoperative American Society of Anesthesiologists physical status; and serum albumin levels.

Functional impairment

Decline in physical function, nutrition, oral function, ADLs, memory, and mood were determined based on responses to 10 questions extracted from the Kihon Checklist upon admission [18]. This 10-question checklist was administered as a standard procedure upon admission of all older patients with spine diseases (Supplementary Table 1). Should there be even one response indicating functional decline in each item, it was considered applicable.

Frailty

Frailty was assessed using the 11-point mFI, which examines 11 factors derived from the patient’s medical records. This index was used to classify our patients into three categories: robust, score = 0; prefrailty, score < 0.21; and frailty, score >0.21 [19].

Locomotive syndrome

Locomotive syndrome stage was determined based on the total GLFS-25 score: stage 0, score ≤ 6; stage 1, score ≥ 7; stage 2, score ≥ 16; and stage 3, score ≥ 24 [20].

Polypharmacy and PIMs

Polypharmacy was defined based on a cutoff of six drugs [21]. According to the guidelines [17], the following 19 categories were considered PIMs requiring special caution when prescribing for older adults: antipsychotics, hypnotics, antidepressants, sulpiride, antiparkinsonian drugs, corticosteroids, antithrombotic drugs, digitalis, diuretics, β-blockers, α-blockers, first-generation antihistamines, H2-receptor antagonists, antiemetic drugs, laxatives, antidiabetic drugs, insulin, overactive bladder medications, and nonsteroidal anti-inflammatory drugs.

Statistical analysis

Data for the two groups were compared using Student’s t-test, Fisher’s exact test, or the Mann–Whitney U test, as appropriate. To assess longitudinal changes in locomotive syndrome stage, the McNemar Bowker test was used. Statistical analyses were performed using the Statistical Package for the Social Sciences (version 29.0; IBM Inc., Armonk, NY, United States), with p values of <0.05 indicating a statistically significant difference.

Results

A total 313 and 103 cases with degenerative lumbar spine diseases (L group) and degenerative cervical spine diseases (C group) were analyzed, respectively (Fig. 1). Table 1 compares the baseline characteristics between the two groups. No significant differences in age, sex, or BMI were observed between the two groups. Medical history revealed a significantly higher frequency of dyslipidemia (p = 0.01) and cancer (p = 0.02) in the L group than in the C group. Although no significant differences were found in the American Society of Anesthesiologists physical status, frailty was significantly more advanced in the C group than in the L group (p = 0.004). Serum albumin levels were significantly lower in the C group than in the L group (p = 0.03). Functional decline in terms of both physical function (p = 0.02) and ADL (p = 0.046) was significantly more frequent in the C group than in the L group. Table 2 compares the frequency of polypharmacy and PIM use. Among 19 medication categories, hypnotics, steroids, antithrombotic drugs, diuretics, H2-receptor antagonists, laxatives, antidiabetic drugs, and nonsteroidal anti-inflammatory drugs were most frequently prescribed. Among these categories, diuretic use was significantly more frequent in the C group than in the L group (p = 0.04). Meanwhile, no significant difference in the frequency of polypharmacy was noted between the two groups. Finally, the pre- and postoperative distribution of locomotive syndrome stages was compared between the groups (Fig. 2). Longitudinal observations showed that the L group experienced significant improvements in locomotive syndrome stages at 6 months and 1 year after surgery (p < 0.001). Conversely, considering that the McNemar Bowker test was used twice, with a p value of 0.025 indicating a significant difference, C group showed no significant changes in locomotive syndrome stages at 6 months (p = 0.040) and 1 year (p = 0.035) after surgery, though marginal changes were observed. Cross-sectional observations indicated no significant differences in locomotive syndrome stage distributions before surgery; however, the C group exhibited significantly more advanced stages at both 6 months and 1 year after surgery than did the L group.

Table 1.

Comparison of baseline characteristics between two groups

		L group (n = 313)		C group (n = 103)		p value
Sex		Men	165 (52.7%)	Men	58 (56.3%)	0.57
		Women	148 (47.3%)	Women	45 (43.7%)
Age (yeas)		75.9 ± 5.9		76.3 ± 5.5		0.44
BMI (kg/m2)		23.7 ± 3.4		23.1 ± 3.9		0.10
Medical history	Diabetes mellitus	86 (27.5%)		35 (34.0%)		0.21
	Hypertension	218 (69.6%)		67 (65.0%)		0.39
	Dyslipidemia	145 (46.3%)		33(32.0%)		0.01
	Cardiovascular disease	90 (28.8%)		24 (23.3%)		0.31
	Stroke	43 (13.7%)		9 (8.7%)		0.23
	Cancer	55 (17.6%)		8 (7.8%)		0.02
ASA	3	42 (13.4%)		10 (9.7%)		0.07
	2	240 (76.4%)		76 (73.8%)
	1	31 (9.9%)		17 (16.5%)
11point- Modified Frailty Index	Frailty	58 (18.5%)		32 (31.1%)		0.004
	Pre-frailty	173 (55.1%)		54 (52.4%)
	Robust	82 (26.1%)		17 (16.5%)
Blood examination Albumin (g/dL)	average	4.09 ± 0.38		3.99 ± 0.39		0.03
Functional impairment	Physical function	114 (36.4%)		52 (50.5%)		0.02
	Nutrition	10 (3.2%)		5 (4.9%)		0.54
	Oral function	17 (5.4%)		5 (4.9%)		0.82
	Activities of daily living	23 (7.3%)		15 (14.6%)		0.046
	Memory	17 (5.4%)		9 (8.7%)		0.24
	Mood	10 (3.2%)		3 (2.9%)		0.89

Student’s t-test, Fisher’s exact test, or the Mann–Whitney U test was used

ASA, SVA Sagittal vertical axis, PI Pelvic incidence, PT Pelvic tilt, LL Lumbar lordosis, FBSS Failed back surgery syndrome

Table 2.

Number and prevalence of cases taking potentially inappropriate medications and polypharmacy

	L group (n = 313)	C group (n = 103)	p value
Antipsychotics	2 (0.6%)	1 (1.0%)	N/A
Hypnotics	70 (22.4%)	23 (22.3%)	1.0
Antidepressants	6 (1.9%)	2 (1.9%)	N/A
Sulpiride	2 (0.6%)	0 (0%)	N/A
Antiparkinsonian agents	1 (0.3%)	0 (0%)	N/A
Corticosteroids	27 (8.6%)	6 (5.8%)	0.41
Antithrombotic drugs	65 (20.8%)	18 (17.5%)	0.57
Digitalis	0 (0%)	2 (1.9%)	N/A
Diuretics	17 (5.4%)	12 (11.7%)	0.04
β-blockers	3 (1.0%)	1 (1.0%)	N/A
α-blockers	12 (3.8%)	3 (2.9%)	N/A
First-generation antihistamines	0 (0%)	2 (1.9%)	N/A
H2-receptor antagonists	17 (5.4%)	6 (5.8%)	0.81
Antiemetic drugs	18 (5.8%)	1 (1.0%)	N/A
Laxatives	44 (14.1%)	12 (11.7%)	0.62
Antidiabetic drugs	52 (16.6%)	23 (22.3%)	0.24
Insulin	9 (2.9%)	3 (2.9%)	N/A
Overactive bladder medications	9 (2.9%)	2 (1.9%)	N/A
NSAIDs	101 (32.0%)	27 (26.2%)	0.27
Polypharmacy	218 (69.4%)	65 (63.1%)	0.23

Fisher`s exact test

NSAIDs non-steroidal anti-inflammatory drugs, N/A Not Applicable

Fig. 2.

Pre- and postoperative distribution of locomotive syndrome stages in the degenerative lumbar spine disease group (L) and degenerative cervical spine disease group (C)

Discussion

The current study has been the first to comprehensively compare geriatric parameters among patients who underwent surgery for degenerative cervical and lumbar spine diseases. Our results indicate that cervical spine diseases were associated with more advanced frailty compared to lumbar spine diseases. Although no significant differences in locomotive syndrome stages were noted between the two conditions before surgery, postoperative improvement in locomotive syndrome was significantly poorer among those with cervical spine diseases.

A comparison of the medical history revealed a significant difference in the frequency of dyslipidemia between the two groups. Moreover, patients with lumbar spine diseases tended to have a higher BMI than those with cervical spine diseases, albeit not significantly, as well as a significantly higher prevalence of dyslipidemia, suggesting a more pronounced metabolic component in the former. These findings are corresponded with previous studies documenting an association between degenerative lumbar disease and lifestyle-related diseases [22–24]. Meanwhile, patients with cervical spine diseases exhibited significantly lower serum albumin levels than did those with lumbar spine diseases. Our assessment, which used part of the Kihon Checklist [18], showed that the decline in physical function and ADLs was more frequent among those with cervical spine diseases than among those with lumbar spine diseases. Considering these results collectively, we can infer that cervical spine diseases exhibit a more pronounced component of frailty than do lumbar spine diseases. Indeed, our assessments using the 11-point mFI showed that frailty was significantly more advanced in those with cervical spine diseases, which directly supports the mentioned hypothesis. Although a previous study reported that frailty in cervical spine disease did not impact postoperative outcomes or improvement in locomotive syndrome [25], this particular study included a limited number of cases and did not offer conclusive evidence. Therefore, we recommend that physicians pay close attention to the increased frequency of frailty when performing surgery on patients with cervical spine disease. Furthermore, because degenerative spine diseases are often treated with not only surgical procedures but also non-surgical interventions [26], this information should be shared with a wide range of healthcare providers, including rehabilitation physicians and physical therapists.

Although the current study only used the GLFS-25 to assess locomotive syndrome, the preoperative distribution of locomotive syndrome stage observed herein corresponded well with those presented in previous reports for both cervical and lumbar spine diseases [27, 28]. In contrast to frailty, no significant differences were found in the preoperative distribution of locomotive syndrome stages between the two diseases, indicating no necessity to specifically focus on one disease over the other before surgery from the perspective of locomotive syndrome. We note, however, that postoperative improvement in locomotive syndrome was significantly poorer among those with in cervical spine diseases than among those with lumbar spine diseases. The current study found no significant postoperative improvement in cervical spine diseases, although marginal p values were obtained. However, previous studies targeting degenerative cervical myelopathy, including OPLL, have reported significant improvements in locomotive syndrome following surgery, indicating a discrepancy in outcomes between the current study and previous research [25, 27]. This discrepancy might have been influenced by our exclusion of cases with OPLL, as well as our exclusive focus on cervical degenerative diseases. However, a review of previous reports confirmed that those with cervical spine disease showed inferior postoperative improvement in locomotive syndrome than did those with lumbar spine disease [27–29]. Significant differences in postoperative improvement of locomotive syndrome between lumbar and cervical spine diseases may be attributed to the fact that lumbar conditions stem from peripheral nerve afflictions, like the cauda equina and nerve roots, whereas cervical conditions originate from central nerve afflictions in the spinal cord, which are inherently more challenging to treat [30]. Regardless, during the process of obtaining informed consent for the surgical treatment of cervical spine disease, patients should receive an explanation that although improvements in mobility, as indicated by the locomotive syndrome stage, can be expected after surgery, the extent of this improvement is likely to be modest.

From the perspective of medication prescription, no significant difference in the frequency of polypharmacy was observed between the two diseases. Among the PIMs frequently prescribed for the two conditions, the reason for the significantly higher frequency of diuretic use in cervical spine disease remains completely unclear. Considering report suggesting increased frequency of diuretic use among frail patients [31], this result may be associated with the significantly higher prevalence of frailty among those with cervical spine diseases than among those with lumbar spine diseases. However, aside from diuretics, hypnotics and antidiabetic drugs, which are classified as drugs that increase fall risk [17], have also been frequently prescribed for both conditions. Considering the inherently high fall risk associated with both diseases [3, 8], the use of these medications could further elevate the fall risk for those with either cervical or lumbar spine diseases. Therefore, special caution regarding falls is particularly necessary for patients with either condition who are taking these medications.

The current study has several limitations. First, the subjects of this study were limited to surgical patients. Given that more cases receive conservative therapy than surgery for both conditions, this study cannot fully elucidate the characteristics of the two diseases. Second, the follow-up duration was only 1 year. Although it would have been preferable to observe outcomes for at least 2 years, a longer evaluation period may increase the difficultly of assessing the impact of surgery alone in clinical studies involving older patients. Third, the relatively high comorbidity rates reported for cervical and lumbar spine diseases suggest that our study population may have included patients suffering from both conditions, making the distinct differentiation between the two diseases challenging [32]. However, to the best of our knowledge, no studies have comprehensively evaluated degenerative spine diseases from the perspective of various clinical aging indices. These findings emphasize that degenerative cervical and lumbar spine diseases should not be regarded as a uniform entity, but rather as conditions with distinct aging-related characteristics. Recognizing these differences may help refine perioperative management and guide the development of more tailored treatment approaches for older adults.

Conclusions

In conclusion, our comparison between cervical and lumbar spine diseases revealed that those with cervical spine disease exhibited more pronounced elements of frailty. Moreover, no significant differences in locomotive syndrome stages were observed between the two groups before surgery; however, those with cervical spine disease experienced inferior postoperative improvement in locomotive syndrome stage, resulting in a significantly more advanced postoperative locomotive syndrome stage among these patients. Taken together, our findings showed that patients with degenerative cervical spine diseases showed more significant progression than those with lumbar spine disease across various indices of aging. Thorough understanding of these characteristics is essential when managing degenerative spine diseases, particularly with regard to the selection of effective treatment approaches.

Abbreviations

ADL

Activities of daily living

mFI

Modified frailty index

PIMs

Potentially inappropriate medications

GLFS-25

25-Question Geriatric Locomotive Function Scale

OPLL

Ossification of posterior longitudinal ligament

BMI

Body mass index

Authors’ contributions

N.F. and S.Y. designed the study. R.K., Y.A., T.M., T.T., R.T., S.K. (Soya Kawabata), S.N., T.I., H. T., and S.K. (Shinjiro Kaneko) contributed to the analysis and interpretation of the data. R.K., Y.A., and T.M. performed statistical analysis. R.K. and N.F. wrote the initial draft of the manuscript. R.K., Y.A., T.M., T.T., R.T., S.K. (Soya Kawabata), S.N., T.I., H. T., S.K. (Shinjiro Kaneko), and S.Y. critically reviewed the manuscript. All authors have read and agreed to the published version of the manuscript.

Funding

This study received no external funding.

Data availability

The datasets generated and/or analyzed during the current study are not publicly available due to the limitations of ethical approval involving patient data and anonymity; however, they are available from the corresponding author on reasonable request.

Declarations

Ethics approval and consent to participate

This research was approved by the Fujita Health University Ethics Committee (approval no. HM 23–354). Informed consent was waived by the Fujita Health University Ethics Committee. The Fujita Health University Ethics Committee also approved our use of the opt-out method for obtaining consent, indicating that all eligible patients were included in the present study unless they contacted us to opt out.

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.