Can a Minimal Clinically Important Difference Be Achieved in Elderly Patients with Adult Spinal Deformity Who Undergo Minimally Invasive Spinal Surgery?

doi:10.1016/j.wneu.2015.09.072

World Neurosurgery

Volume 86, February 2016, Pages 168-172

https://doi.org/10.1016/j.wneu.2015.09.072 Get rights and content

Background

Older age has been considered a relative contraindication to complex spinal procedures. Minimally invasive surgery (MIS) techniques to treat patients with adult spinal deformity (ASD) have emerged with the potential benefit of decreased approach-related morbidity.

Objective

To determine whether a minimal clinically important difference (MCID) could be achieved in patients ages ≥65 years with ASD who underwent MIS.

Methods

Multicenter database of patients who underwent MIS for ASD was queried. Outcome metrics assessed were Oswestry Disability Index (ODI) and visual analog scale (VAS) scores for back and leg pain. On the basis of published reports, MCID was defined as a positive change of 12.8 ODI, 1.2 VAS back pain, and 1.6 VAS leg pain.

Results

Forty-two patients were identified. Mean age was 70.3 years; 31 (73.8%) were women. Preoperatively, mean coronal curve, pelvic tilt, pelvic incidence to lumbar lordosis mismatch, and sagittal vertical axis were 35°, 24.6°, 14.2°, and 4.7 cm, respectively. Postoperatively, mean coronal curve, pelvic tilt, pelvic incidence to lumbar lordosis, and sagittal vertical axis were 18°, 25.4°, 11.9°, and 4.9 cm, respectively. A mean of 5.0 levels was treated posteriorly, and a mean of 4.0 interbody fusions was performed. Mean ODI improved from 47.1 to 25.1. Mean VAS back and leg pain scores improved from 6.8 and 5.9 to 2.7 and 2.7, respectively. Mean follow-up was 32.1 months. For ODI, 64.3% of patients achieved MCID. For VAS back and leg pain, 82.9% and 72.2%, respectively, reached MCID.

Conclusions

MCID represents the threshold at which patients feel a meaningful clinical improvement has occurred. Our study results suggest that the majority of elderly patients with modest ASD can achieve MCID with MIS.

Introduction

Older age has long been considered a relative contraindication to spinal fusion, given the concern for possible increased morbidity and poorer outcomes compared with decompression alone. In recent years, however, studies have shown that elderly patients older than 65 years of age can derive significant benefit from decompression and fusion for degenerative spinal disease without significantly increased morbidity.1, 2, 3 These studies have focused primarily on short segment fusions for degenerative conditions such as stenosis and spondylolisthesis.

Spinal deformity also can be a cause of significant pain and disability in the elderly patient that often requires more complex, multilevel spinal surgery to treat appropriately. Reports regarding outcomes involving the elderly patients with adult spinal deformity (ASD) who undergo spinal surgery are scarce, although in 1 study Daubs et al.⁴ showed that significant clinical improvement could be obtained in patients ages 60 years and older. Recently, minimally invasive surgery (MIS) approaches have been used to treat patients with ASD, with the potential benefit of decreased approach-related morbidity.5, 6, 7, 8 Similar to the relative paucity of literature focusing on the elderly and traditional open spinal surgery, there has been little investigation involving the elderly with ASD who undergo MIS. The objective of this study was to determine whether a minimal clinically important difference (MCID) could be achieved in patients 65 years of age and older who underwent MIS for ASD.

Section snippets

Methods

In this study, each participating site received institutional review board approval before submitting data to create a multicenter database of patients who underwent MIS for ASD. Inclusion criteria for this database were a diagnosis of ASD with at least 1 of the following radiographic parameters: coronal curve (CC) ≥20°, sagittal vertical axis (SVA) >5 cm, pelvic tilt (PT) >25°, or thoracic kyphosis >60°. A total of 190 patients were entered into the database, which was composed of those who

Results

Mean age was 70.3 (standard deviation [SD], 4.9) years, and 31 (73.8%) of the patients were female. A mean of 4.0 (SD, 1.5) interbody fusions were performed, and a mean of 5.0 (SD, 2.8) levels were treated posteriorly. Five of the 42 patients had undergone LLIF without posterior instrumentation. Mean estimated blood loss was 507.7 mL (SD, 537.3), and mean length of stay was 7.5 days (SD, 4.1). Complications occurred in 14 (33.3%) patients. Eight patients had at least 1 major complication, and 7

Discussion

In the current study, the large majority of elderly patients undergoing MIS for ASD achieved the MCID in key patient-reported outcome (PRO) measures. PROs are now used commonly to determine the impact of spinal surgery. The ODI is a validated instrument for assessing functional outcome, whereas the VAS instrument is used widely to assess pain. Although the ODI and VAS provide an objective means of recording a change in patient status after spinal surgery, the numerical values have no direct

Conclusions

The MCID represents the threshold at which patients perceive that a meaningful clinical improvement has occurred after treatment. The results of this study suggest that the majority of elderly patients with ASD, who primarily have CCs, can achieve MCID with MIS. Further studies determining MCID for ASD patients are needed, as are investigations of MCID involving elderly patients with more significant sagittal plane deformities.

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Cited by (29)

Estimating measurement error of the Oswestry Disability Index with missing data
2022, Spine Journal
The Oswestry Disability Index (ODI) is the most commonly used patient-reported outcome measure for low back pain. Incomplete ODI questionnaires may induce measurement error, causing misclassification of disability level.
We determined which scoring method—alternative scoring (AS) or multiple imputation (MI)—produced the best estimate of measurement error with missing items; and assessed the precision of AS and MI when scoring the ODI and classifying disability level with increasing numbers of missing items.
Quantitative study
We included 995 patients who underwent lumbar spine surgery from 2014 to 2020 and who had complete ODI data.
Measurement error.
We (1) simulated 1000 datasets for each number of ODI items (1–9) for which data could be missing by randomly setting items to missing; (2) calculated simulated scores using AS or MI; (3) calculated absolute percentage error (APE) of simulated vs. true scores; (4) classified disability level using the simulated score; and (5) compared APE between scoring methods to assess precision and misclassification rates.
For 1, 5, and 9 missing items using AS, APE was 0.6%, 3.1%, and 12%, respectively, and misclassification rates were 0.6%, 4.6%, and 13%. For 1, 5, and 9 missing items using MI, APE was 1.3%, 7.9%, and 56%, respectively, and misclassification rates were 4.6%, 9.7%, and 58%, respectively.
With increasing numbers of missing ODI items, MI introduced more measurement error than AS did. Clinicians should consider APE when interpreting ODI scores with missing data and classifying disability level. Inaccurate interpretations could negatively affect assessments and treatment plans.
IV
Conflating effect size and minimal clinically important difference. Comment on Br J Anaesth 2021; 126: 1029–37
2022, British Journal of Anaesthesia
The role of less invasive surgery in the treatment of adolescent idiopathic scoliosis and adult spinal deformity
2021, Orthopaedics and Trauma
Citation Excerpt :
A PubMed/Medline search from 2015 to 2020 using ‘MISS’, ‘adult spine’ and ‘deformity’ as key words was able to isolate 68 papers. Publications by the International Spine Study Group (ISSG) suggested that the majority of elderly patients with modest ASD can achieve MCID (positive changes on ODI and VAS) with MIS.12 Both hybrid and circumferential MIS (cMIS) approaches resulted in clinical improvement, as evidenced by decreased ODI and VAS pain scores.
The overall impact of spinal deformity reconstructive surgery on short- and long-term quality of life and patients' perioperative experience has been widely studied in recent literature. With the advancement of modern less invasive (anterior/lateral/posterior percutaneous) spinal deformity techniques the ‘gold standard’ role of open traditional approaches has been questioned. Minimally invasive surgical (MIS) techniques are rapidly evolving and further research is required to determine whether a particular surgical treatment may be suitable for all patients or a patient-tailored individual treatment and surgical technique should be selected and could offer better results. Focus of the present article is to report the most recent research in ‘pure’ less invasive spinal deformity surgery (LIS) as applied both for adolescent idiopathic scoliosis (AIS) and adult spinal deformity (ASD) and describe a single centre's experience on such ‘treatment philosophy’ as adopted in the last 7 years.
Use of robotics and novel technologies in spine surgery in elderly patients
2020, Seminars in Spine Surgery
Citation Excerpt :
A review by Shamji et al. found that minimally invasive techniques, such as decompression alone, decompression and interbody fusion, and deformity correction, are technically feasible and safe in elderly individuals.30 Several other studies describe the safety and efficacy of MIS approaches for lumbar interbody fusion and spine deformity in elderly patients.31,32,33,34 Robotic assistance allows the surgeon to plan trajectories and place pedicle screws without the extensive muscle and soft tissue dissection needed for open surgery.
As our global population ages, the demand for surgical treatment of spinal disorders in elderly patients has increased. The elderly population poses a unique challenge to spine surgeons due to multiple medical comorbidities and increased likelihood of complications. Robotics are being used for pedicle screw placement to enhance accuracy of placement and minimize surgical invasiveness. Although the use of robotics has not been studied specifically in elderly patients, this population may benefit significantly from the use of robotics as a minimally invasive technique to minimize blood loss, decrease operative time, and lessen postoperative pain—ultimately reducing complications.
Is it sufficient to treat adult lumbar spinal deformity using anterior lumbar interbody fusion with percutaneous pedicle screw fixation?
2020, Journal of Clinical Neuroscience
Citation Excerpt :
Patients with adult degenerative scoliosis include elderly individuals. The majority of elderly patients with modest degenerative scoliosis achieved minimal clinically significant differences in outcome following MIS.[25] Park et al.[26] also reported another comparative study of hybrid (HYB) and circumferential MIS (cMIS) approaches for the treatment of adult spinal deformity.
Anterior lumbar interbody fusion (ALIF) has been performed for lumbar spinal restoration and stabilization without extensive paraspinal muscle damage or massive bleeding. The authors retrospectively investigated surgical results of multilevel ALIF followed by percutaneous pedicle screw fixation (PPSF) in adult lumbar spinal deformity (ALSD). This study included 28 patients with degenerative lumbar spinal deformity, who underwent selective multilevel ALIF and PPSF between January 2013 and August 2016 at our hospital. Standing X-rays were performed and coronal Cobb angle (CCA) of scoliosis, sagittal vertical axis (SVA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic tilt (PT), and sacral slope (SS) were measured. Pain and functional assessment were performed using visual analogue scale (VAS) scores for low back pain and leg pain, and Oswestry Disability Index (ODI) scores. CCA, SVA and LL were significantly improved immediately after surgery and relatively well maintained until the last follow-up. After surgery, PT was significantly decreased and SS was increased, respectively. However, cases with SVA > 95 mm or PT > 30° showed a loss of correction in sagittal balance parameters to a greater extent at the last follow-up compared to the group of patients with minor sagittal imbalance. VAS scores for back and radicular pain, and ODI score were significantly decreased at the final follow-up (p < 0.05). Multilevel ALIF with PPSF yielded favorable clinical and radiological outcomes in coronal and sagittal balance without severe surgical mortality or morbidity in patients with ALSD. However, correction loss in sagittal balance was observed in cases with SVA > 95 mm or PT > 30˚.
When do patients truly reach maximal medical improvement after undergoing reverse shoulder arthroplasty? The incidence and clinical significance of pain and patient-reported outcome measure improvement
2020, JSES International
Patients receiving reverse total shoulder arthroplasty (RTSA) may reach MMI prior to 12 months postoperatively.
With the growth of RTSA indications, there is a paucity of information regarding maximum medical improvement (MMI) after these procedures. Systems of evaluating recovery, such as patient-reported outcome measures and minimal clinically important differences (MCIDs) will allow for measurement of when patients reach maximum medical improvement (MMI) after these procedures.
To evaluate when patients have reached MMI after RTSA.
Patients were prospectively enrolled in the institution's RTSA registry. All patients undergoing RTSA who agreed to be enrolled were included. Patient-specific factors, American Shoulder and Elbow Surgeons Standardized Shoulder Assessment Form (ASES) score, and pain data were collected preoperatively and at 6 and 12 months postoperatively. Subgroup analysis was performed on preoperative diagnosis before analyzing MCID and MMI. MMI was calculated by using the last time point interval that an MCID did not occur.
Of 182 patients, 92 had complete 12-month postoperative data, including visual analog scale (VAS) pain and ASES scores. Subgroup analysis showed preoperative diagnosis of rotator cuff arthropathy, revision surgery, glenohumeral arthritis, proximal humerus fracture, and chronic dislocation. All 5 groups had improvement that exceeded MCID thresholds at 6 months and variable improvement from 6-12 months. Analysis of variance compared the different groups, showing that VAS pain scores and ASES scores were different at all time points except for preoperative VAS pain scores.
Patients undergoing RTSA may reach MMI at 6 months instead of the previously reported 1-year time point. Data from this study can allow providers to deliver value care and potentially limit visits after 6 months postoperatively.

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: Conflict of interest statement: The authors report the following: N.A.: consultant for Medtronic, Globus Medical, and Baxano Surgical; direct stock ownership in Globus Medical and Medtronic; receiving royalties from Medtronic, Globus Medical, NuVasive, and Baxano Surgical. V.D.: consultant for NuVasive, Guidepoint, and Stryker’ A.S.K.: consultant for NuVasive; receiving royalties from Lanx. F.L.M.: consultant for Globus Medical and Biomet; patent holder with Globus Medical; receiving nonstudy-related clinical/research support from Globus Medical. P.V.M.: direct stock ownership in Spinicity; receiving royalties from DePuy Spine, Quality Medical Publisher, and Thieme Publishers; received honoraria from Globus Medical. G.M.M.: consultant for and receiving royalties from NuVasive and K2M. D.O.O.: receiving royalties from Lanx. P.P.: consultant for Medtronic, Globus Medical, and Biomet; receiving royalties from Globus Medical; receiving nonstudy-related clinical/research support from Orthofix, Blue Care Blue Cross Foundation. C.I.S.: consultant for Biomet, Globus Medical, Medtronic, NuVasive, and Stryker; patent holder with Biomet and Medtronic; receiving royalties from Biomet and Medtronic. J.S.U.: consultant for NuVasive. M.Y.W.: consultant for Aesculap Spine and DePuy Spine; patent holder with DePuy Spine.

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Original ArticleCan a Minimal Clinically Important Difference Be Achieved in Elderly Patients with Adult Spinal Deformity Who Undergo Minimally Invasive Spinal Surgery?

Background

Objective

Methods

Results

Conclusions

Introduction

Section snippets

Methods

Results

Discussion

Conclusions

Spine J

Spine J

Spine J

J Clin Epidemiol

Instrumented intervertebral or posterolateral fusion in elderly patients: clinical results of a single center

BMC Musculoskelet Disord

Effects of age on the perioperative characteristics and short-term outcome of posterior lumbar fusion surgery

J Neurosurg Spine

Adult spinal deformity surgery: complications and outcomes in patients over age 60

Spine (Phila Pa 1976)

Original Article
Can a Minimal Clinically Important Difference Be Achieved in Elderly Patients with Adult Spinal Deformity Who Undergo Minimally Invasive Spinal Surgery?