Surgery in the elderly population is still a debatable issue. Boundaries between overtreatment and standard of care are often undefined and unclear; therefore, surgeons and anesthesiologists should evaluate surgical indications, as well as predict the complications, to balance the risks and benefits for patients [15]. Decision-making in the surgical management of elderly patients also has to consider the role of frailty and disability, aiming to obtain the best results with minimal risks for the delicate general homeostasis of the aging population.

Minimally invasive techniques applied to spinal surgery have gained appeal over the past decade, as they have demonstrated good clinical outcomes and low complication rates along with the well-known advantages of low invasiveness [4, 16, 17]. Currently, various spinal diseases (degenerative, neoplastic, or traumatic) may be approached using MISS techniques, with reduced blood loss, limited muscular dissection, better control of postoperative pain, and decreased hospitalization time [18]. To state the philosophy of MISS: elderly patients should be considered ideal candidates for spine surgery using less invasive techniques. Advances in MISS devices and techniques have led to an overall increase of surgical procedures in elderly patients, as demonstrated by the growing number of recently published reports on this topic [19–21].

In 2008, Lee et al. analyzed the clinical and radiological outcomes of 27 patients, aged over 65 years old, who underwent single-level m-open TLIF as surgical treatment for degenerative spondylolisthesis [19]. They documented a high fusion rate (77.8 %), good spinal realignment (improved segmental lordosis in all patients), and a low complication rate. However, a possible inclusion bias in their series could be related to the patients’ American Society of Anesthesiologists (ASA) grading, with a score ranging between 1 and 2 in all enrolled patients.

In 2011, Drazin et al. reviewed clinical data from the literature on complications and outcomes after spinal deformity surgery in patients over60 years old [7]. Interestingly, they supported the application of minimally invasive techniques in order to reduce the complication rate, encouraging future studies in this direction. A further review published in 2014 [22] highlighted the scant number of adequate clinical studies on this topic, pointing out the importance of CT scans for the thorough evaluation of fusion rates. Indeed, most of the published studies, including the previously cited one by Lee et al. [19], did not use CT scans in radiological follow-up.

A recent review of the existing literature on MISS in elderly patients [20] revealed a good clinical outcome with an acceptable complication rate, albeit that all the published studies reviewed had low-quality evidence, based on retrospective series. The authors concluded that symptomatic elderly patients may benefit from MISS techniques and they should not be excluded from surgery.

We have reported our experience with minimally invasive techniques in the surgical treatment of different spinal pathologies in a consecutive cohort of patients aged over 65 years old. Differently from Lee’s series, we included patients regardless of their ASA score or surgical techniques, aiming to observe the impact of MISS in improving clinical outcome and allowing a rapid recovery. Early patient mobilization and short hospitalization have been considered primary goals, and surgical indications have been advised accordingly. We included in this series 20 patients suffering from traumatic and osteoporotic vertebral fractures. In this subgroup, minimally invasive techniques (PPSF with or without cement augmentation or expandable screws, or simple vertebro/kyphoplasty) ensured rapid recovery from symptoms, with unequivocal clinical advantages, as documented by a reduction of the VAS score from 9.3 to 3.2 (considering only patients with vertebral fractures). In this subgroup, we observed only one case of screw displacement, requiring revision surgery. Moreover, we combined PPSF and cement augmentation of the fractured vertebral body in 5 of these 20 patients, following the positive clinical experience with such a technique reported by Gu et al. [21]. Short-segment percutaneous fixation has been proposed as a viable alternative to open posterolateral fusion in patients with thoracolumbar burst fractures [23, 24]; in our series, short fixation with expandable or fenestrated screws for cement augmentation and short screws in the pedicles of fractured vertebrae were used in 8 of 24 patients, whereas 10 patients underwent percutaneous fixation with screws placed two levels above and two levels below the fractured vertebra.