Spondylolisthesis (SL) is defined as the slippage of one vertebra relative to the vertebra below it. It can be anterior (ante-listhesis) or posterior (retro-listhesis) [1]. Its historical classification by Wiltse [2] distinguishes six aetiological types. Degenerative spondylolisthesis (DS) (type III) is the most common form in older people [3].

In this study conducted in West Africa, particularly in Côte d’Ivoire, we defined an elderly person as someone aged 60 or over, in accordance with the epidemiological criteria and recommendations of the World Health Organisation (WHO) for developing countries [4].

The prevalence of Degenerative spondylolisthesis increases significantly with age [3], estimated at up to 30% between the ages of 65 and 69 in some populations [5]. It is the result of segmental instability due to disc degeneration and osteoarthritis of the facet joints [6]. Established risk factors include female gender, advanced age, obesity or overweight, and multiparity [7].

The aim of our study was to describe the epidemiological, clinical and radiological characteristics of lumbar spondylolisthesis in elderly patients seen at the rheumatology clinic at Bouaké University Hospital.

Lumbar spondylolisthesis in elderly subjects (N = 113) accounted for 41.2% of all LS cases recorded during the period (274 cases in total). The study population was predominantly female, with 100 women to 13 men (88.5%), giving a male-to-female ratio of 0.13. The average age was 66.9 ± 6.1 years, with extremes of 60 and 88 years. The 60 - 70 age group accounted for 74.3% of cases (Figure 1).

Figure 1. Distribution of patient age groups by gender.

Housewives were the most affected (72.6%). The average BMI was 24.1 ± 4.7 kg/m² (ranging from 15.8 to 37.6 kg/m²). The BMI was normal in 55 patients (54.4%). Overweight and obesity were noted in 35 patients (34.7%) (Table 1).

Pain was the reason for consultation in all cases (100%). In 12.4% of cases, it was isolated low back pain. In 87.6% of cases, it was lumbosacral radiculopathy. Neurogenic claudication was present in 85.8% of cases of lumbar radicular pain. The condition was chronic in 85.8% of cases, with symptoms developing gradually in 91.2% of patients.

Radiologically, the displacement was anterior (ante-listhesis) in all our patients (Figure 2).

Table 1. Distribution of patients according to body mass index.

NB: in 12 cases, the body mass index was not specified. 101 corresponds to the number of patients with a calculated body mass index.

Figure 2. Anelisthesis (red arrow) due to grade I isthmic lysis (green arrow) (white dot) on L4-L5 discarthrosis.

Degenerative spondylolisthesis was the most common aetiology, accounting for 80.5% of cases. In all cases, it was associated with spondylotic and posterior interapophyseal osteoarthritis. Spondylolisthesis due to isthmic lysis (Figure 2), which accounted for 19.5% of cases, was always associated with degenerative lesions in this elderly population in our study. The L4-L5 and L5-S1 levels were affected (Table 2).

Table 2. Distribution of elderly patients according to the stage affected.

Analytically, there was a link between the occurrence of degenerative spondylolisthesis and age, with a p-value (Mantel-Haenszel) of 0.019 and an odds ratio of 1.97.

Age is a determining and omnipresent factor in the development and progression of spondylolisthesis, particularly the degenerative form [3]. The role of age is intrinsically linked to the ageing process of the mobile spinal segment, leading to a cascade of biomechanical changes that promote vertebral slippage.

Our results confirm the clear predominance of females (88.5%) in the elderly population, a well-established risk factor for degenerative spondylolisthesis [7], often linked to hormonal and biomechanical factors, particularly multiparity.

The role of BMI is a notable point in our series. The average BMI was 24.1 kg/m², and 34.7% of our patients were overweight or obese. Although 54.4% of patients had a normal BMI, the high proportion of overweight/obese patients (nearly one-third) confirms the importance of weight as a biomechanical risk factor [7]. Excess weight significantly increases stress on the L4-L5 lumbar segment, the most common site of degenerative spondylolisthesis. This increased mechanical stress, combined with disc and facet degeneration, drives the progression of slippage and associated symptoms [8][9].

The clinical presentation of lumbosacral radiculopathy with neurogenic claudication in more than 85% of cases is characteristic of lumbar spinal stenosis (LSS), which is frequently associated with DS [9]. Vertebral slippage, facet hypertrophy and ligament thickening lead to compression of the nerve roots, explaining the disabling symptoms.

Radiologically, the finding that degenerative spondylolisthesis (DS) accounts for the majority of cases (80.5%) in the elderly is a classic observation in the international literature [3]. DS, classified as type III by Wiltse et al. [2], is by definition an acquired condition linked to advancing age.

Spondylolysis (Wiltse type II), on the other hand, is a condition acquired during childhood or adolescence, linked to an isthmus fracture [2]. However, the key finding in elderly subjects is that Spondylolysis (SLI) is always associated with degenerative lesions in our cohort. This observation is a typical phenomenon in the long-term natural history of SLI [10].

For decades, disruption of the posterior arch (lysis) causes chronic instability, which inevitably accelerates degeneration of the disc and residual joint facet joints [10]. Thus, the clinical and radiological picture of SLI in older subjects is often confused with DS: low back pain and neurogenic claudication (frequently associated with DS [9]) result from aggravated instability and stenosis of the lumbar canal secondary to associated degeneration.

Lumbar spondylolisthesis in elderly patients is a common condition in our hospital setting, with a clear predominance in women and a degenerative etiology. The clinical picture is dominated by chronic lumbosacral radiculopathy with neurogenic claudication.

Gender: □ Male □ Female

Age: ……………………..years

Age group: □ 60 - 70 □ 70 - 80 □ 80 - 90 □ <90

Occupation: ……………………………………….

Reason for consultation: ……………………………………….

Progression: □ acute □ subacute □ chronic

Schedule: □ mechanical □ inflammatory

Irradiation: □ yes □ no

Neurogenic claudication: □ yes □ no

Body mass index: ……………………………… kg/m²

Imaging performed: □ standard X-ray □ lumbar scan

Mechanism of spondylolisthesis: □ degenerative □ isthmolysis

Type of spondylolisthesis: □ ante listhesis □retrolisthesis

Grade of spondylolisthesis: □ grade I □ grade II □ grade III

Level of involvement: □ L2/L3 □ L3/L4 □ L4/L5 □L5/S1