Activity of Daily Living After Long Level Fusion in Adult Spinal Deformity: Compared With Over 60-Year-Old Degenerative Spine Patients Without Adult Spinal Deformity

Stiffness-related disability following long segmental posterior instrumentation and fusion: is it influenced by postoperative spinopelvic alignment?

PURPOSE

The aims of this study were to investigate the correlations between Chinese version of Lumbar Stiffness Disability Index (C-LSDI) and other clinical outcomes, and to identify the factors independently affecting stiffness-related disability after long-segment fusion in patients with degenerative lumbar scoliosis (DLS).

METHODS

We performed a retrospective study of 118 consecutive surgically treated DLS cases at a single institute. Pre- and post-operative radiological parameters and postoperative health related quality of life (HRQOL) were examined to determine their correlation coefficients with postoperative C-LSDI. Patients were divided into two groups by the medium number of postoperative C-LSDI: low-stiffness group (C-LSDI < 48 points) and high-stiffness group (C-LSDI ≥ 48 points). Subsequently, differences between the two groups were assessed, and the presumed factors affecting C-LSDI evaluation were further analyzed.

RESULTS

Coronal parameters and global sagittal parameters showed significant correlations with postoperative C-LSDI. The correlation coefficients between C-LSDI and Oswestry Disability Index (ODI), Japanese Orthopedic Association-29 (JOA-29), the Scoliosis Research Society-22 questionnaire (SRS-22) Function, and the Short Form-36 Health Survey (SF-36) Physical Component Scores were over 0.5. In multiple linear regression, postoperative sagittal vertical axis (β = 0.084, p = 0.025), fusion levels (β = 2.13, p = 0.012), and body mass index (β = 0.867, p = 0.022) were independent related factors for C-LSDI.

CONCLUSION

This study showed that all HRQOLs demonstrated the varying degree of correlations with C-LSDI, of which the ODI, JOA-29, SRS-22 Function, and SF-36 PCS were most relevant, with moderate strength of associations.Moreover, longer fusion levels, higher BMI, and greater postoperative SVA independently affect C-LSDI after long segmental posterior instrumentation and fusion for DLS.

Time-Dependent Changes in Stiffness-Related Functional Disability After Long Segmental Fusion in Elderly Patients With Adult Spinal Deformity-Minimum 2-Year Follow-up Results

BACKGROUND

Although several studies were performed to measure stiffness-related functional disability (SRFD) after long segmental fusion for adult spinal deformity, the evaluation of SRFD was done at a single point in time. We do not know whether the disability will stay the same, worsen, or improve over time.

OBJECTIVE

To evaluate the time-dependent changes of SRFD and any factors affecting these changes.

METHODS

Patients who had ≥4-segment fusion with the sacrum were reviewed retrospectively. Specific Functional Disability Index (SFDI), consisting of a 12-item tool with 4 categories (sitting on the floor, sanitation activities, lower body activities, and moving activities), was used to assess the severity of SRFD. The SFDI taken at 3 months, 1 year, and 2 years postoperatively and at the last follow-up were used for evaluating the changes in SRFD. The presumed factors affecting these changes were analyzed.

RESULTS

This study included 116 patients. Total SFDI scores significantly improved from 3-month to the last follow-up. Among the 4-category of SFDI, sitting on the floor showed the highest scores followed by lower body activities, sanitation activities, and moving activities at all time points. All categories except for sitting on the floor showed significant improvement from 3 months until the last follow-up. This improvement was most pronounced between 3 months and 1 year. American Society of Anaesthesiologists grade was identified as the only factor affecting time-dependent changes.

CONCLUSION

SRFD was highest at 3 months, but it improved over time except for sitting on the floor. The improvement was observed greatest between 3 months and 1 year. Patients with less American Society of Anaesthesiologists grade experienced more improvement in SRFD.

Pelvic incidence is a risk factor for lower instrumented vertebra failure in adult spinal deformity patients who underwent corrective fusion terminating at the L5 vertebra

BACKGROUND

Factors related to postoperative mechanical failure after long fusion with lower instrumented vertebra (LIV) at L5 have not been well investigated. Elucidating such factors may allow us to perform alternatives to spinopelvic fusion for adult spinal deformity (ASD) cases. We investigated the incidence and risk factors of LIV failure in patients with ASD who underwent surgical treatment of long corrective fusion until the L5 vertebrae.

METHODS

Between 2009 and 2018, 52 patients who underwent corrective fusions to L5 were followed-up for at least one-year. We evaluated the associated patient factors for LIV failure which include loosening of the pedicle screw of LIV, fracture of LIV, distal junctional kyphosis (DJK).

RESULTS

The mean age of the participants was 71.2 ± 7.59 (range, 44-84). LIV failure occurred in 20 patients (38.5%), and 6 patients (11.5%) underwent secondary surgery for caudal segments. The mean pelvic incidence (PI) was 52.5 ± 9.8 in the failure group versus 45.3 ± 11.4 in non-failure group (P = 0.02) and pelvic tilt (PT) was 39.1 ± 9.0 versus 32.4 ± 13.0. There were no significant differences in sex, age, body mass index, number of levels fused, and other radiographic data. Logistic regression analysis that included T1 pelvic angle, PT, PI - postoperative LL and PI also identified PI as the only significant determinant of LIV failure (OR = 1.07, P = 0.034). Receiver operating characteristic analysis demonstrated that a PI over 50.0° was associated with LIV failure (sensitivity 63%, specificity 70%, AUC 0.694).

CONCLUSION

LIV failure was frequently observed after long corrective fusion for patients with ASD. High PI was found to be a significant risk factor for the LIV failure.

The Most Significant Factor Affecting Gait and Postural Balance in Patients’ Activities of Daily Living Following Corrective Surgery for Deformity of the Adult Spine

Background and Objectives: Gait ability and spinal postural balance affect ADL in patients who underwent adult spinal deformity (ASD) surgery. However, it is still unclear how to determine what the cause is. This study was done to investigate various factors affecting gait, postural balance and activities of daily living (ADL) in patients who were operated on for ASD over a period of one year, following corrective surgery. Materials and Method: A cohort of 42 (2 men, 40 women, mean age, 71.1 years) who were operated on for ASD were included in this study. According to Oswestry Disability Index (ODI), based on their ADL, patients were segregated into satisfied and unsatisfied groups. Gait and postural balance abilities were evaluated before and after the operative procedure. Radiographs of spine and pelvis as well as the rehabilitation data (static balance, standing on single-leg; dynamic postural adaptation, timed up and go test (TUG); Gait Capability, walk velocity for a distance of 10 m) were acquired 12 months after surgery and analyzed. Spinopelvic parameters such as (lumbar lordosis (LL), pelvic tilt (PT), sagittal vertical axis (SVA), pelvic incidence (PI)) were marked and noted. The factors which affect patients’ satisfaction with their ADL were evaluated. Results: The ADL satisfied group included 18 patients (1 man, 17 women, mean age 68.6 years) and the unsatisfied group included 24 patients (1 man, 23 women, mean age 73.1 years). One year after the surgery, the two groups were tested. TUG (8.5 s vs. 12.8 s), 10 m walk velocity (1.26 m/s vs. 1.01 m/s), and single leg standing test (25 s vs. 12.8 s) were regarded as notably different. According to logistic regression analysis, only TUG was extracted as a significant factor. The cut-off value was 9.7 s, with sensitivity 75%, specificity 83%, area under the curve 0.824, and a 95% confidence interval of 0.695–0.953. Conclusions: A significant factor among all evaluations in postoperative ASD patients was TUG, for which the cut-off value for ADL satisfaction was 9.7 s.

Factors Affecting Stiffness-Related Functional Disability After Long Segmental Fusion for Adult Spinal Deformity

BACKGROUND

In general, stiffness-related functional disability (SRFD) is expected to increase as longer fusion length, but there have been no studies on factors affecting SRFD besides fusion length.

OBJECTIVE

To identify the factors affecting SRFD after long segmental fusion in patients with adult spinal deformity (ASD).

METHODS

We retrospectively reviewed the patients who underwent ≥4-segment fusion including sacrum for ASD. The severity of SRFD was evaluated using the Specific Functional Disability Index (SFDI) consisting of 12 items with 4 categories as follows: sitting on the floor, sanitation activity, lower body activity, and moving activity. Each category contains 3 items which was given a maximum of 4 points. The presumed factors affecting SFDI were analyzed.

RESULTS

A total of 148 patients were included in the study with their mean age of 67.3 years. The mean fusion length was 6.4 segments. The mean score of each SFDI category was highest in sitting on the floor (9.9), followed by lower body activities (7.6), sanitation activities (6.0), and moving activities (5.9). The total sum was 29.3 points. In multivariate analysis, total sum of SFDI was significantly higher in female sex, patients with higher American Society of Anesthesiology grade, and longer fusion length. However, the sagittal parameters did not show a significant correlation with SRFD, except pelvic incidence-lumbar lordosis which correlated with only one category (lower body activities).

CONCLUSION

This study showed that female sex, higher American Society of Anesthesiology grades, and longer fusion length influenced SRFD after long segmental fusion for ASD. Sagittal parameters related to the degree of deformity correction did not significantly affect SRFD.