Importance of modifiable non-radiographic functional parameters for adult spinal deformity.

We clarified non-radiographic physical parameters associated with the severity of adult spinal deformity (ASD) using community-dwelling adult volunteers. They were subjected to upright entire spine radiographs for standard radiographic parameters and the number of sagittal modifiers of SRS-Schwab ASD classification (Schwab-SM). Clinical evaluations included isometric muscle strength of trunk extensor (TEX), trunk flexor (TFL), quadriceps femoris (QF), gluteus maximus, and iliopsoas; range of motion (ROM) of hip, knee, ankle, and active back extension (BET); SF36 physical component score (PCS), VAS for back and knee pain, and the degree of ambulatory kyphosis (dTIA). Each muscle strength was calibrated by body weight (BW) and expressed as BW ratio. According to our previous study, dTIA ≥ 7.6° was defined as pathological and dTIA ≤ 3.5° as normal. A final total of 409 female volunteers were included, and their demographics were; age 67.0 ± 5.5 years, Schwab-SM 2.1 ± 1.8, TEX 0.90 ± 0.33BW, TFL 0.48 ± 0.15BW, QF 0.45 ± 0.19BW, PCS 33.5 ± 6.5. Subjects were classified as clinical ASD group (cASD, n = 10) with PCS ≤ 27(mean-1SD) and pathological dTIA, robust group (n = 19) with PCS ≥ 40 (mean + 1SD) and normal dTIA, and the rest (non-cASD, n = 338). Statistical analyses showed significant differences in TEX, TFL, QF, knee extension (KEX), and BET between robust and cASD, and the mean values of robust group (TEX ≥ 1.1BW, TFL ≥ 0.5BW, QF ≥ 0.5BW, KEX ≥ 0° and BET ≥ 14 cm) were used as 'ASD-MJ' index. Subjects with fully achieving ASD-MJ goals showed significantly better radiographic and clinical outcomes than those with unmet goals. In conclusion, upon prescribing conservative or physical therapies for ASD patients, modifiable clinical goals should be clarified, and ASD-MJ could be a benchmark.

Physical and radiographic features of degenerative retrolisthesis in Japanese female volunteers: an observational cohort study.

Hundred and twenty four females with spondylolisthesis were divided into three groups (A group: anterolisthesis; P group: retrolisthesis; and AP group: antero-retrolisthesis), We reviewed their whole-spine radiographs and measured their standard sagittal parameters, including thoracic kyphosis (TK), pelvic incidence (PI), lumbar lordosis (LL), pelvic tilt (PT), and sacral slope (SS). The muscle strengths of the trunk flexor, trunk extensor, iliopsoas, and quadriceps were measured. Health-related quality of life was assessed using the Short Form 36-item Health Survey-physical component summary (SF-36 PCS). PI, SS, and LL-TK of participants in the P group were significantly lower than those in the A and AP groups (PI: P group vs. A group, p < 0.001, P group vs. AP group, p = 0.01), (SS: P group vs. A group, p = 0.001, P group vs. AP group, p = 0.003), (LL-TK: P group vs. A group, p < 0.001, P group vs. AP group, p = 0.049). TK of participants in the P and AP groups was greater than that of those in the A group. (P group vs. A group, p = 0.04, AP group vs. A group, p = 0.0025). The SF-36 PCS score in the P group was lower than that in the A and AP groups. (P group vs. A group, p = 0.004, P group vs. AP group, p = 0.012). The muscle strengths of the trunk flexor and trunk extensor and quadriceps in the P group were lower than those in the A groups. (Trunk flexor: P group vs. A group, p = 0.012), (Trunk extensor: P group vs. A group, p = 0.018), (Quadriceps: P group vs. A group, p = 0.011). In conclusion, female participants with degenerative retrolisthesis had a smaller PI and SS and a larger TK, along with decreased physical function and QoL scores than those with anterolisthesis.

Examination of the changes in lower extremities related to progression of adult spinal deformity: a longitudinal study of over 22 years.

This longitudinal observational study investigated the relationship between changes in spinal sagittal alignment and changes in lower extremity coronal alignment. A total of 58 female volunteers who visited our institution at least twice during the 1992 to 1997 and 2015 to 2019 periods were investigated. We reviewed whole-spine radiographs and lower extremity radiographs and measured standard spinal sagittal parameters including pelvic incidence [PI], lumbar lordosis [LL], pelvic tilt [PT], sacral slope [SS] and sagittal vertical axis [SVA], and coronal lower extremity parameters including femorotibial angle (FTA), hip-knee-ankle angle (HKA), mechanical lateral distal femoral angle (mLDFA), mechanical medial proximal tibial angle (mMPTA) and mechanical lateral distal tibial angle (mLDTA). Lumbar spondylosis and knee osteoarthritis were assessed using the Kellgren-Lawrence (KL) grading system at baseline and at final follow-up. We investigated the correlation between changes in spinal sagittal alignment and lower extremity alignment and changes in lumbar spondylosis. The mean age [standard deviation (SD)] was 48.3 (6.3) years at first visit and 70.2 (6.3) years at final follow-up. There was a correlation between changes in PI-LL and FTA (R = 0.449, P < 0.001) and between PI-LL and HKA (R = 0.412, P = 0.001). There was a correlation between changes in lumbar spondylosis at L3/4 (R = 0.383, P = 0.004) and L4/5 (R = 0.333, P = 0.012) and the knee joints. Changes in lumbar spondylosis at L3/4 and L4/5 were related to changes in KOA. Successful management of ASD must include evaluation of the state of lower extremity alignment, not only in the sagittal phase, but also the coronal phase.

Adult spinal deformity and its relationship with height loss: a 34-year longitudinal cohort study.

BACKGROUND: Age-related height loss is a normal physical change that occurs in all individuals over 50 years of age. Although many epidemiological studies on height loss have been conducted worldwide, none have been long-term longitudinal epidemiological studies spanning over 30 years. This study was designed to investigate changes in adult spinal deformity and examine the relationship between adult spinal deformity and height loss. METHODS: Fifty-three local healthy subjects (32 men, 21 women) from Furano, Hokkaido, Japan, volunteered for this longitudinal cohort study. Their heights were measured in 1983 and again in 2017. Spino-pelvic parameters were compared between measurements obtained in 1983 and 2017. Individuals with height loss were then divided into two groups, those with degenerative spondylosis and those with degenerative lumbar scoliosis, and different characteristics were compared between the two groups. RESULTS: The mean age of the subjects was 44.4 (31-55) years at baseline and 78.6 (65-89) years at the final follow-up. The mean height was 157.4 cm at baseline and 153.6 cm at the final follow-up, with a mean height loss of 3.8 cm over 34.2 years. All parameters except for thoracic kyphosis were significantly different between measurements taken in 1983 and 2017 (p < 0.05). Height loss in both sexes was related to changes in pelvic parameters including pelvic incidence-lumbar lordosis (R = 0.460 p = 0.008 in men, R = 0.553 p = 0.012 in women), pelvic tilt (R = 0.374 p = 0.035 in men, R = 0.540 p = 0.014 in women), and sagittal vertical axis (R = 0.535 p = 0.002 in men, R = 0.527 p = 0.017 in women). Greater height loss was more commonly seen in women (p = 0.001) and in patients with degenerative lumbar scoliosis (p = 0.02). CONCLUSIONS: This longitudinal study revealed that height loss is more commonly observed in women and is associated with adult spinal deformity and degenerative lumbar scoliosis. Height loss is a normal physical change with aging, but excessive height loss is due to spinal kyphosis and scoliosis leading to spinal malalignment. Our findings suggest that height loss might be an early physical symptom for spinal malalignment.

Evaluation of a new apparatus combining a mobile device and hand-held roller for the detection of spinal deformities: association with the sum of the right and left angles of trunk inclination.

PURPOSE: To investigate the intra- and inter-observer reliabilities of the newly developed i-Scolioroller for scoliosis screening, and to determine the optimal i-Scolioroller measurement cutoff values for identifying adolescent scoliosis with a Cobb angle ≥ 20°. METHODS: The i-Scolioroller displays the right- and left-side maximum inclination angle (Rmax, Lmax) during the forward bending test (FBT), as well as the angle of trunk inclination (ATI, i.e., whether the Rmax or Lmax is greater). Sum-ATI is defined as the sum of Rmax and Lmax. Intra-class correlation coefficients (ICC) of the ATI and sum-ATI measurements were calculated to analyze the intra- and inter-observer reliabilities for 10 plaster torsos in FBT positions obtained from patients with idiopathic scoliosis. The optimal cutoff values for scoliosis were determined using receiver operating characteristic (ROC) analysis of i-Scolioroller measurements versus Cobb angles obtained from the upright whole-spine radiographs of 112 adolescent outpatients. RESULTS: The intra-observer ICCs for the ATI/sum-ATI for 3 observers were 0.851/0.856, 0.786/0.900, and 0.772/0.796, respectively, while the corresponding inter-observer ICCs for all participants were 0.733/0.745. On ROC analysis, an ATI of 8° was the optimal cutoff value for scoliosis (sensitivity and specificity: 79.2% and 70.0%, respectively). The optimal cutoff value for sum-ATI was 11° (sensitivity and specificity: 86.1% and 82.5%, respectively). The areas under the ROC curves were 0.859 for ATI and 0.908 for sum-ATI. CONCLUSION: The optimal cutoff values for identifying scoliosis using the i-Scolioroller were a combination of 11° for the sum-ATI and 8° for the ATI.

Classification of arm swing as a clinical marker of advancing spinal deformity among community-dwelling female volunteers 60 years or older.

The clinical characteristics of adult spinal deformity (ASD) include worsening of deformity during gait, which leads to unstable posture and propensity to fall. The purpose of this study was to classify arm swing and to analyse its clinical implications. Clinical and radiographic evaluations were performed with 168 community-dwelling female volunteers recruited from a population register in Hokkaido, Japan, with a mean age of 67.3 ± 4.7 years, and arm swing was classified into four groups according to maximum forward and backward arm swing distance: (1) predominantly forward swing with forward swing always larger than backward swing (FS, n = 138), (2) equal or equivocal swing (ES, n = 8), (3) predominantly backward swing with backward swing always larger than forward swing (BS, n = 20), and (4) thigh-hand type without arm swing with their hands placed on thighs (TH, n = 2). BS and FS showed significant differences in radiographic lumbar lordosis (BS 19.4 ± 18.1° vs. FS 40.6 ± 14.5°, P < 0.01 ANOVA), pelvic tilt (BS 40.0 ± 7.3° vs. FS 22.9 ± 8.9°, p < 0.01), number of vertebral fractures (BS 1.2 ± 1.4 vs. FS 0.3 ± 0.6, p < 0.01), and trunk extensor muscle strength (BS 374.9 ± 134.8 N vs. FS 478.1 ± 172.6 N, p < 0.05). Arm swing correlated with severity of radiographic ASD, osteoporotic changes, and back muscle weakness. The number of ASD patients, which includes patients with de novo/idiopathic scoliosis, degenerative/osteoporotic kyphosis, and other neuromuscular deformities, has been increasing, and further study should clarify the importance of dynamic evaluation of ASD among elderly patients.

Clinical evaluation of surgery for osteophyte-associated dysphagia using the functional outcome swallowing scale.

PURPOSE: To investigate the surgical outcome of patients with osteophyte-associated dysphagia (OAD) using the functional outcome swallowing scale (FOSS). METHODS: A retrospective chart review of 10 surgical cases of OAD (9 male and 1 female patient; mean age of 65 years) from 1982 to 2017 was performed, and radiographic evaluations were conducted by video fluoroscopic swallow study (VFSS) and conventional radiography. All OAD cases were treated at a single institution, and osteophytes were surgically resected by the anterior approach under gentle retraction of the affected esophagus. FOSS (0 for normal, 5 for worst) was used for clinical evaluations, and surgical complications were recorded. RESULTS: VFSS evaluation of OAD showed that the affected osteophyte was located at C4/5 in four patients, followed by C3/4 in three patients. The mean FOSS showed significant improvement from 2.5 preoperatively to 0.3 postoperatively, and no major surgical complications were recorded. Comorbidities were diabetes mellitus in four patients, ossification of the posterior longitudinal ligament in three patients, and lumbar spinal stenosis (LSS) in three patients. CONCLUSION: Surgical treatment of OAD was promising, and all patients showed clinical recovery. Evaluation of dysphagia using FOSS was easy and reliable for OAD management, and FOSS 2 might be a good indication for surgical intervention.

Spatial geometric and magnetic resonance signal intensity changes with advancing stages of nucleus pulposus degeneration.

BACKGROUND: With advancing stages of degeneration, denaturation and degradation of proteoglycans in the nucleus pulposus (NP) lead to tissue dehydration and signal intensity loss on T2-weighted MR images. Pfirrmann grading is widely used for grading degeneration of intervertebral discs (IVDs). The criterion to differentiate IVDs of Pfirrmann Grade I from the other grades is NP homogeneity. Pfirrmann grading is qualitative and its assessment may be subjective. Therefore, assessment of quantitative objective measures correlating with early disc degeneration may complement the grading. This study aimed to evaluate the applicability of the distance between the center weighted by signal intensity (weighted center) and the geometric center as a parameter of NP homogeneity. Other phenomena related to advancing stages of degeneration were also investigated. METHODS: MR images of 65 asymptomatic volunteers with a total of 288 lumbar IVDs with clearly identifiable nucleus pulposus boundary (Pfirrmann Grade I, II and III) were included in this study. A custom-written program was developed to determine the IVD longitudinal axis, define the NP boundary, and to locate the coordinates of geometric and weighted NP centers on the mid-sagittal image of each studied IVD. The distances between the weighted and geometric centers on the longitudinal axis and the perpendicular axis of each IVD were calculated. RESULTS: The weighted center located posterior to the geometric center, which indicated the signal intensity was lower at the anterior portion of the NP, in 85.8% of studied IVDs. The distance between the weighted and geometric center on the longitudinal axis was significantly shorter in homogeneous (Pfirrmann Grade I) than in inhomogeneous (Grade II) IVDs. The distance on the perpendicular axis in Grade III IVDs was significantly larger than that in Grade I and Grade II IVDs. CONCLUSION: The relationship between the weighted and geometric centers can serve as an indicator for NP homogeneity. The distance between both centers through advancing stages of degeneration demonstrated decrease of signal intensity progressing along the longitudinal axis initially and then along the cranio-caudal direction at later stages. These findings could provide insights of initiation and subsequent progression of degenerative changes in IVDs.

Clinical, physical, and radiographic analyses of lumbar degenerative kyphosis and spondylolisthesis among community-based cohort.

PURPOSE: To investigate longitudinal radiographic changes, and physical characteristics of lumbar degenerative kyphosis (LDK) and spondylolisthesis (DS). METHODS: Two-hundred eighty nine community-based female subjects were recruited from population register and studied longitudinally for a mean 12.3 years. Upright entire spine radiographs were used to evaluate spinopelvic parameters, including lumbar lordosis (LL), pelvic incidence (PI), and vertebral slip (% slip). Physical measurements included lumbar range of motion (ROM), isometric trunk muscle strength, and photometric gait posture using change in trunk inclination angle (dTIA). RESULTS: Subjects' mean age (standard deviation: SD) was 56.9 (10.0) years at baseline and 68.5 (9.2) years at the final follow-up. Among 202 subjects who could perform instructed physical measurements, DS, defined as more than 5 % slip, was found in 50 subjects (24.8 %), and LDK, defined as LL of less than 1SD of mean value (<24.4°), was found in 24 subjects (11.9 %). DS subjects showed a significant weakness in trunk flexor strength (normal 282.5 ± 73.0 N vs. DS 245.5 ± 75.5 N, p = 0.0219), and LDK subjects showed significant differences in: trunk extensor strength (normal 493.4 ± 172.8 N vs. LDK 386.3 ± 167.6 N, p = 0.0066), ROM, and dTIA (normal 3.5° ± 2.7° vs. LDK 7.6° ± 4.8°, p < 0.0001). PI was significantly larger in DS and smaller in LDK than normal subjects (normal 53.8° ± 9.9° vs. DS 58.2° ± 10.6°, p = 0.0111; normal vs. LDK 48.4° ± 9.2°, p = 0.0191). CONCLUSIONS: Current study showed that DS was associated with reduced trunk flexor strength, which might increase pelvic anteversion, and LDK was associated with reduced extensor strength, ROM, and ambulatory kyphosis. Physical characteristics should be evaluated for the successful management of adult spinal deformity.

In vivo 3-dimensional morphometric analysis of the lumbar foramen in healthy subjects.

STUDY DESIGN: In vivo 3-dimensional (3D) morphometric analysis of the lumbar foramen by using 3D computed tomographic models in normal subjects. OBJECTIVE: To describe foraminal geometry in an asymptomatic cohort measured in 3D. SUMMARY OF BACKGROUND DATA: Appropriate assessment of the complex 3D lumbar foraminal geometry is key to correct radiculopathy diagnosis and treatment planning. To the best of our knowledge, there is no other study that quantifies the normal lumbar foramen 3D geometry considering sex, age groups, and spinal levels in vivo. METHODS: Subject-based 3D computed tomographic lumbar models were created in 59 asymptomatic volunteers and foraminal height and width were measured on the basis of the model by custom software. The foraminal height and width were compared by sex, age, and lumbar level. RESULTS: Overall, the foraminal height decreased with age. However, although the foraminal height in males decreased with age at all spinal levels, the foraminal heights in females did not. The foraminal height was significantly larger in the upper lumbar levels in both sexes. The foraminal width in males was significantly smaller than in females for all age groups. The foraminal width in both sexes also decreased similarly with age. The foraminal widths at the lower lumbar levels were significantly smaller than those at the upper levels. Age-related foraminal width decreases were seen in all lumbar levels as well. CONCLUSION: This study described foraminal geometry in vivo in an asymptomatic cohort measured in 3D. Age-related foraminal height decrease was noticeable in males and in the lower lumbar levels. Age-related foraminal width decrease was shown in both sexes and in all lumbar levels. Such information can be used as baseline data for diagnosis of foraminal stenosis and treatment modality planning.