A new surgical method to treat intracanal lumbar disc herniation using the unilateral biportal endoscopic transforaminal approach: patient series.

BACKGROUND: Unilateral biportal endoscopic lumbar discectomy (UBELD) is a new minimally invasive spine surgery. The purpose of this study is to describe a new surgical method to treat intracanal lumbar disc herniation (LDH) using the unilateral biportal endoscopic transforaminal approach (UBE-TFA). The first 15 patients who had undergone UBELD for single-level LDH were included in this study. Operative time, intraoperative blood loss, postoperative stay, and intraoperative complications were recorded. The Oswestry Disability Index (ODI), numeric rating scale (NRS) score for leg pain, and modified MacNab criteria were assessed at 3 months postoperatively. OBSERVATIONS: The mean operative time was 52.0 ± 13.8 minutes. The mean intraoperative blood loss was 10.5 ± 10.2 mL. The mean postoperative stay was 1.1 ± 0.3 days. There were no complications. The postoperative mean ODI was significantly improved from 44.9 ± 14.4 to 7.7 ± 11.2 at the final follow-up (p < 0.001). There was a significant decrease in the postoperative mean NRS score for leg pain, from 6.1 ± 1.9 to 0.8 ± 1.3 at the final follow-up (p < 0.001). Based on the modified MacNab criteria, good to excellent results were obtained in 86.7% of the patients. LESSONS: We considered UBELD-TFA as not only one of the promising surgical methods for UBELD, but also a new surgical implementation of the TFA.

Relationship between dysphagia and motor function in community-dwelling older people.

AIM: Dysphagia is a problem typically associated with aging. The aim was to investigate the relationship between dysphagia and motor function using a simple assessment method that can be performed in the community setting, and to promote the early detection and prevention of dysphagia. METHODS: Data from the Locomotive Syndrome and Health Outcome in Aizu Cohort Study (LOHAS) were used. Those aged ≥65 years were included. Motor function was assessed using a grip strength test, single limb standing test (SLS), and timed up and go test (TUG). Swallowing function was assessed using the Japanese version of the 10-item Eating Assessment Tool (EAT-10). The association between motor function and swallowing function was analyzed. RESULTS: In total, 1732 participants were included. In logistic regression modes in which grip strength, SLS, and TUG results were included separately, the odds ratio for dysphagia increased by 1.08 (P = 0.001) for each 1-kg decrease in grip strength, and increased by 1.15 (P < 0.001) for each 1-s increase in TUG time. No association was found for SLS. In the model in which grip strength and TUG were included simultaneously, the odds ratio for dysphagia increased by 1.06 (P = 0.01) in grip strength, and increased by 1.11 (P = 0.009) in TUG time. CONCLUSION: Our results suggest that skeletal muscle strength and dynamic balance function are associated with dysphagia in community-dwelling older people. Geriatr Gerontol Int 2023; 23: 603-608.

Relationship between lumbar facet joint osteoarthritis and comorbidities: A cross-sectional study in the Japanese community.

BACKGROUND: Few epidemiological studies have evaluated associations between lumbar facet joint (LFJ) osteoarthritis (OA) and comorbidities. This study aimed to investigate the prevalence of LFJ OA in a Japanese community population and associations between LFJ OA and underlying diseases, including lower extremity OA. METHODS: This epidemiological cross-sectional study evaluated LFJ OA in 225 Japanese community residents (81 males, 144 females; median age, 66 years) using magnetic resonance imaging (MRI). LFJ OA from L1-L2 to L5-S1 was evaluated using a 4-grade classification. Associations between LFJ OA and comorbidities were examined using multiple logistic regression analyses adjusting for age, sex, and body mass index. RESULTS: Prevalences of LFJ OA were 28.6% at L1-L2, 36.4% at L2-L3, 48.0% at L3-L4, 57.3% at L4-L5, and 44.2% at L5-S1. Males were significantly more likely to have LFJ OA at several spinal levels (L1-L2 45.7% vs 18.9%, p < 0.001; L2-L3 46.9% vs 30.6%, p < 0.05; L4-L5 67.9% vs 51.4%, p < 0.05). LFJ OA was present in 50.0% of residents <50 years old, 68.4% at 50-59 years old, 86.3% at 60-69 years old, and 85.1% at ≥70 years old. Multiple logistic regression analysis showed no associations between LFJ OA and comorbidities. CONCLUSIONS: The prevalence of LFJ OA as evaluated by MRI was >85% at ≥60 years old and highest at the L4-L5 spinal level. Males were significantly more likely to have LFJ OA at several spinal levels. Comorbidities were not associated with LFJ OA.

Delayed Pyogenic Spondylitis at the Same Level as Rod Fracture After Surgery for Adult Spinal Deformity: A Case Report.

CASE: Rod fracture (RF) occurred at L5-S level in a 79-year-old woman 7 months after spinal corrective surgery for adult spinal deformity (ASD). Four years after the surgery, pyogenic spondylitis occurred at the same level as RF. After the reinforcement of broken rods posteriorly, a transperitoneal approach was used for debridement and bone graft. However, prolonged infection, adhesive ileus, and small bowel perforation led to a total of 3 reoperations, resulting a colostomy. Three years after the reoperation, she was ambulatory with assistance. CONCLUSION: We need to follow-up postoperative ASD patients carefully because a single complication can lead to serious consequences.

Age-Related Differences in the Limited Range of Motion of the Lower Extremity and Their Relation to Low Back Pain in Young Baseball Players: A Cross-Sectional Study of 1215 Players.

BACKGROUND: Age-related differences in the limited range of motion of the lower extremities and their relationship with low back pain in juvenile athletes have not been well assessed. This study investigated the relationship between low back pain and limited range of motion of the hip and knee in young baseball players during the baseball season. RESULTS: Participants comprised 1215 baseball players (216 pitchers, 999 fielders) aged 6-16 years who underwent medical checkups (self-completed questionnaire and physical examination). Of the 1215 players, 255 (21.0%) experienced seasonal low back pain requiring rest during the previous year. The prevalence of low back pain and a positive Thomas test, straight-leg-raising test, and heel-to-buttock test increased with age. Univariate analysis revealed that a positive heel-to-buttock test in both the throwing and non-throwing arm sides in the 11-12 age group and a positive Thomas test in the throwing arm side in the 13-14 age group were associated with seasonal low back pain (P = 0.0051, P = 0.021, and P = 0.048, respectively). Multivariate analysis, adjusted for factors associated with low back pain, showed significant associations between the positive heel-to-buttock test (odds ratio 1.75, 95% confidence interval 1.11-2.79; P = 0.016) and low back pain in players aged 11-14 years. CONCLUSIONS: A positive heel-to-buttock test is potentially associated with low back pain among juvenile baseball players. Particular attention should be paid to the limited range of motion of the knee joint and tightness of the quadriceps femoris muscle among baseball players with low back pain aged 11-14 years.

Impact of low back pain experience on future occurrence of shoulder pain in adolescent baseball players: A 1-year prospective cohort study.

BACKGROUND: Low back pain can affect musculoskeletal problems of the upper limb in adolescent overhead athletes. However, few epidemiological studies have examined this causal relationship. This prospective cohort study aimed to investigate the relationship between baseline low back pain experience and the occurrence of future shoulder and elbow pain among high school baseball players. METHODS: Participants comprised 383 high school baseball players from 43 high school baseball teams who had undergone baseline medical evaluations (a self-completed questionnaire and physical examination). The occurrence of shoulder and elbow pain during a 1-year follow-up and associations with baseline low back pain (positive subjective symptom during the last year at baseline) adjusted for flexibility of the scapulo-thoracic region, shoulder, and lower extremities, such as straight-leg raise angle (hamstring tightness), Thomas test (iliopsoas tightness), heel-buttock-distance (quadriceps tightness) and passive range of motion of the hip were investigated using multivariable analysis. RESULTS: A total of 307 players (80.2%) participated in the 1-year follow-up survey, with shoulder and elbow pain reported in 75 players (24.4%) and 119 players (38.8%), respectively, during follow-up. After adjusting for factors associated with shoulder pain using logistic regression modeling, significant associations between LBP experienced during the last year at baseline (odds ratio, 2.18; 95% confidence interval, 1.23-3.87; P = 0.0078) and new-onset of shoulder pain were noted. CONCLUSIONS: Baseline low back pain impacted future shoulder pain in high school baseball players during the 1-year follow-up. Management of shoulder pain warrants careful attention to low back pain.

Minimally Invasive Spinal Fusion Using Percutaneous Pedicle Screw Instrumentation Can Provide a Better Health-Related QOL in Early Stage Than Conventional Methods in the Treatment of Single-Level Degenerative Lumbar Spinal Diseases.

Purpose: To investigate whether the minimally invasive spinal fusion can provide the better outcome than conventional fusion surgery in the treatment of degenerative lumbar spinal diseases. Patients and Methods: One hundred and thirteen patients who had undergone single-level fusion surgery for degenerative lumbar spinal diseases were examined with a minimum of one-year follow-up. There were 56 men and 57 women with a median age of 70s ranging 47-88. The following three-types of fusion surgery were performed; minimally invasive transforaminal interbody fusion after microscopic decompression through a unilateral approach with percutaneous pedicle screwing (MTLIF), transforaminal interbody fusion after microscopic decompression through a unilateral approach (TLIF), and posterior lumbar interbody fusion with posterolateral fusion after open decompression through a bilateral approach (PLIF). The purpose for limiting on single level degenerative spinal disease was that it would be easy to compare the surgical outcomes among the three groups. Results: There were no statistically significant differences among three groups in terms of VAS scores, RDQ scores, and all of the domains in the JOABPEQ scores at the baseline. The JOABPEQ score for pain-related disorders at 6 months after surgery was statistically significantly higher in MTLIF group than the other two groups (P = 0.023). There were no statistically significant differences in the scores of the other outcome measures among three groups in whole follow-up period. Conclusion: The current study demonstrated that the JOABPEQ score for pain-related disorders at 6 months postoperatively was significantly better in MTLIF group than in the other groups. Since lumbar degenerative diseases mostly consisted in elderly patients, less invasive surgeries are desirable. MTLIF resulted in a better health-related QOL at 6 months after surgery, and its outcomes at the final follow-up were non-numerical inferiority. The results strongly indicate that MTLIF is desirable surgery especially for elderly patients with degenerative spinal diseases.

The association of dynamic spinal alignment on gait endurance of patients with adult spinal deformity: a cross-sectional study.

PURPOSE: The purpose of this study was to evaluate the gait posture of patients with adult spinal deformity (ASD) using a 3-dimensional motion analysis system (3DMAS) and to investigate whether it affects gait endurance. METHODS: Fifty-one patients with ASD aged 50 years or older who were admitted to our hospital between March 2016 and March 2018 were included in the study. The subjects completed the 6-min walking test, which is an indicator of gait endurance. Static standing posture was assessed by whole-spine x-ray examination (coronal cobb angle, CCA; sagittal vertical axis, SVA; pelvic tilt, PT; and pelvic incidence minus lumbar lordosis, PI-LL). In addition, the gait posture was evaluated by a 3DMAS (dynamic trunk tilt angle, DTA; and dynamic pelvic tilt angle, DPA). The relationship between standing and gait postures and gait endurance was investigated by multivariable analysis. RESULTS: In univariable analysis, SVA, PI-LL, and DTA were associated with gait endurance. Furthermore, in the multivariable analysis, DTA showed the strongest association among the static and dynamic parameters (R2 = 0.61, ß = - 0.35, P < 0.05). CONCLUSIONS: An association was found between gait posture and gait endurance in patients with ASD. These findings can be useful to health care providers treating patients with ASD. It is advisable to assess the gait posture of patients with ASD because they present postural abnormalities during gait.

Generalization of a clinical diagnosis support tool for lumbar spinal stenosis: Can the ankle brachial pressure index be replaced by palpation of the posterior tibial artery in the lumbar spinal stenosis diagnostic support tool? (DISTO project).

BACKGROUND: The Japanese Society for Spine Surgery and Related Research previously developed a diagnostic support tool for lumbar spinal stenosis (LSS-DST). Using the LSS-DST, general physicians can identify potential cases of LSS. However, in the LSS-DST, measurement of the ankle brachial pressure index (ABI) is required to exclude peripheral artery lesions in the lower limbs. We can expect further application of the LSS-DST if we can identify a simpler and easier method than ABI measurement. Therefore, in this large-scale, multicenter, cross-sectional study, we verified whether palpation of the posterior tibial (PT) artery could be used instead of ABI in the LSS-DST. METHODS: This survey was conducted at 2177 hospitals and included 28,883 participants. The sensitivity and specificity of the original LSS-DST method using the ABI and that of the LSS-DST ver2.0 with PT artery palpation were assessed to screen their ability for diagnosing LSS, using the physicians' final diagnosis based on the patients' history, physical examination and radiographic findings as the gold standard. RESULTS: The sensitivity and specificity [95%CI] of the LSS-DST were 88.2% [87.5, 88.8] and 83.9% [83.4, 84.5], respectively, whereas the sensitivity and specificity of the LSS-DST ver2.0 were 87.7% [87.0, 88.3] and 78.3% [77.7, 78.9], respectively, indicating that LSS-DST ver2.0 is a useful screening tool for LSS with good sensitivity. CONCLUSION: When the item of ABI in the LSS-DST is replaced by palpation of the PT artery (LSS-DST ver2.0), its sensitivity is maintained as a screening tool for LSS. LEVEL OF EVIDENCE: Level 3.

Lumbar spinal stenosis is a risk factor for the development of dementia: locomotive syndrome and health outcomes in the Aizu cohort study.

PURPOSE: It remains unclear whether musculoskeletal diseases are risk factors for dementia development. This prospective cohort study of community-dwelling residents aimed to clarify the impact of lumbar spinal stenosis (LSS) on dementia development. METHODS: We included participants aged ≥ 65 years from the Locomotive Syndrome and Health Outcomes in the Aizu cohort study. LSS was diagnosed using the validated LSS diagnostic support tool. Dementia development between 2008 and 2015 was investigated using official long-term care insurance certification data. We analysed the effects of LSS on dementia development after adjusting for potential confounders, like age, sex, diabetes, depressive symptoms, hip and knee joint osteoarthritis, daily activity, and smoking habit. RESULTS: We included 1220 patients in the final analysis. The incidence of dementia was significantly higher in the LSS group [48 of 444 (10.8%)] than in the control group [34 of 776 (4.4%)]. Multivariable analysis using multiple imputations revealed that the confidence interval for the adjusted odds ratio of LSS for dementia development was 1.87 (95% confidence interval; 1.14-3.07). CONCLUSION: We clarified that LSS is an independent risk factor for dementia development. Our findings suggest the importance of considering the risk of dementia in the decision-making process for the treatment of LSS.

Diagnostic accuracy of the lumbar spinal stenosis-diagnosis support tool and the lumbar spinal stenosis-self-administered, self-reported history questionnaire.

Despite the applicability of the lumbar spinal stenosis (LSS)-diagnosis support tool (DST) and the LSS-self-administered, self-reported history questionnaire (SSHQ), their diagnostic accuracy has never been compared with that of the well-known North American Spine Society (NASS) clinical description of LSS. This study aimed to compare the diagnostic accuracy of the two diagnostic tools with that of the NASS guidelines' clinical description of LSS in a Japanese secondary care hospital setting. This multicenter cross-sectional study used data from the lumbar spinal stenosis diagnostic support tool (DISTO) project, which was conducted from December 1, 2011 to December 31, 2012. Japanese adults with low back pain (LBP) aged ≥20 years were consecutively included. The reference standard was LSS diagnosed by orthopedic physicians. The diagnostic accuracy of the two support tools was compared. Of 3,331 patients, 1,416 (42.5%) patients were diagnosed with LSS. The NASS clinical description of LSS had a sensitivity of 63.9% and specificity of 89.5%. The LSS-DST and LSS-SSHQ had sensitivities of 91.3% and 83.8% and specificities of 76.0% and 57.6%, respectively, with substantial improvements in sensitivity (P < 0.0001). Similar results were obtained when we limited included patients to those aged >60 years. These findings indicated that the LSS-DST and LSS-SSHQ were more sensitive in screening patients with LBP for a diagnosis of LSS than the NASS clinical description of LSS. This study strongly supports prioritizing the use of either of these two diagnostic support tools for screening.

Relationship between Lower Limb Pain Intensity and Dynamic Lumbopelvic-Hip Alignment in Patients with Degenerative Lumbar Spinal Canal Stenosis: A Cross-Sectional Study.

STUDY DESIGN: This cross-sectional study was conducted in a single hospital. PURPOSE: To clarify the relationship between lower limb pain intensity and dynamic lumbopelvic-hip alignment in patients with lumbar spinal canal stenosis (LSS), using a three-dimensional (3D) motion analysis system. OVERVIEW OF LITERATURE: Although it is well known that leg symptoms have a close relationship with posture in patients with LSS, the relationship under dynamic conditions, such as gait, remain unclear. METHODS: Thirty patients with LSS scheduled for spine surgery participated in this study. Lower limb pain was assessed using the Visual Analog Scale (VAS), and the patients were divided into two groups based on the mean scores (patients with scores above and below the mean were classified as the high-VAS and low-VAS groups, respectively). The kinematics of the spine, pelvis, and hip joints during gait were then measured using a 3D motion analysis system. Student paired t -tests were used to compare the angles of the spine, pelvis, and hip during gait between the two groups. RESULTS: Compared to those in the low-VAS group, the spine was significantly extended and bent toward the more painful lower limb side, and the pelvis was significantly anteriorly tilted among individuals in the high-VAS group. CONCLUSIONS: Patients with LSS experiencing severe pain in their lower limb tend to keep the spine in a more extended position, bend laterally toward the painful side, and have an anteriorly tilted pelvic posture. The dynamic spinal and pelvic alignment was closely related to the intensity of the lower limb pain.

Maximum gait speed and lumbar spinal mobility can affect quality of life in elderly women with lumbar kyphosis.

Background: The site and angle of kyphosis are important factors that affect quality of life (QOL). Lumbar kyphosis, rather than thoracic kyphosis, is reported to affect the QOL in patients with kyphosis. Increased angle of kyphosis in elderly people is associated with a decline in motor and physical functions, and also correlates with reduced QOL. Investigation of how physical performance affects their QOL would be helpful in developing an effective physical therapy program for elderly patients with kyphosis. The aims of the current study were to evaluate the physical performance including back muscle strength, spinal range of motion, and walking ability in elderly patients with lumbar kyphosis, and to examine its association with back pain-specific QOL. Methods: The design of this study is a cross-sectional study in a single hospital. A total of 51 elderly women aged 65 years or older diagnosed with kyphosis were enrolled in the study. The items evaluated were back pain (visual analog scale [VAS]), back-pain specific QOL (the Oswestry Disability Index [ODI]), maximum gait speed, thoracic kyphosis angle, lumbar lordosis angle, sacral inclination, spinal inclination, trunk extension/flexion range of motion (ROM), thoracic spinal ROM, lumbar spinal ROM, and back muscle strength. Data were analyzed using bivariate analyses and multivariate regression analyses. Results: Significant positive correlations were observed between ODI and VAS (rs=0.506) or spinal inclination (rs=0.626). Significant negative correlations were observed between ODI and maximum gait speed (rs=-0.664), lumbar lordosis angle, (rs=-0.553), trunk extension ROM (rs=-0.571), lumbar spinal ROM (rs=-0.651), or back muscle strength (rs=-0.521). Multiple regression analysis demonstrated that maximum gait speed (standard partial regression coefficient; b=0.484) and lumbar spinal ROM (b=0.463) had a significant impact on ODI. The results of analysis of variance were significant with R2 of 0.622. Conclusions: The current study demonstrated that maximum gait speed and lumbar spinal ROM influenced back-pain specific QOL in the elderly women with lumbar kyphosis. Maximum gait speed and lumbar spinal ROM should be evaluated thoroughly to effectively perform non-operative treatment in elderly people with lumbar kyphosis.

Hip Extensor Strength Influences Dynamic Postural Changes during Gait in Patients with Adult Spinal Deformity: A Cross-Sectional Study Using Three-Dimensional Motion Analysis.

STUDY DESIGN: Single-hospital cross-sectional study. PURPOSE: The aim of the present study was to investigate the physical functions influencing dynamic postural change in patients with adult spinal deformity (ASD). OVERVIEW OF LITERATURE: Dynamic postural change leading to increased forward lean during gait is a problem in patients with ASD; however, the relationship between this change and trunk and hip extensor strength is unclear. METHODS: Thirty patients with ASD aged ≥50 years who were admitted to our hospital between July 2016 and September 2019 were included in this study. X-ray parameters (i.e., sagittal vertical axis, pelvic tilt, and pelvic incidence minus lumbar lordosis) were evaluated from the full-length standing radiographs of the subjects. Trunk and hip extensor strength was evaluated using a hand-held dynamometer. Dynamic postural changes (i.e., sagittal trunk shift during standing, sagittal trunk shift during gait, and delta sagittal trunk shift) were assessed using a three-dimensional motion analysis system. The relationships between dynamic postural change and various X-ray parameters, as well as trunk and hip extensor strength, were examined using multivariable analysis. RESULTS: Multivariable analysis showed that hip extensor strength is the factor most strongly associated with dynamic postural change among the X-ray parameters and physical functions assessed in this study (ß=-0.41, R2=0.12). CONCLUSIONS: We demonstrated the association between dynamic postural change and hip extensor strength in patients with ASD. Our results may be useful to healthcare providers treating patients with ASD. Interventions for dynamic postural change in patients with ASD should focus on hip extensor strength.

Associations between core stability and low back pain in high school baseball players: A cross-sectional study.

BACKGROUND: Reduced core stability is a potential risk factor for low back pain in athletes. However, the association between core stability and low back pain in high school baseball players has not been thoroughly studied. The purpose of this study was to investigate the relationship between core stability and low back pain and its clinical characteristics in high school baseball players. METHODS: Participants comprised 812 high school baseball players who had undergone annual medical evaluations, comprising a self-completed questionnaire and a physical examination. We investigated the relationships between low back pain during the season and on the day of medical evaluations and core stability using a cross-sectional study design. Core stability was assessed using the Sahrmann core stability test. RESULTS: Reduced core stability was confirmed in 358 (44.1%) of all players, 98 (49.5%) pitchers, and 260 (42.3%) fielders. In total, 352 players (43.3%) reported incidents of seasonal low back pain during the previous year. Thirty-five pitchers (17.7%) and 153 fielders (24.9%) reported low back pain on the day of the medical evaluations. No significant associations were seen between low back pain throughout the season and reduced core stability. After adjusting for confounding factors (total amount of practice per week, hamstring tightness and quadriceps tightness) using logistic regression modeling, a significant association between presence of low back pain during lumbar extension movement and reduced core stability was found (odds ratio, 2.57; 95% confidence interval, 1.08-6.62; P = 0.033) in pitchers. CONCLUSIONS: High school baseball pitchers with reduced core stability showed a higher probability of reporting low back pain during lumbar extension movement. Evaluation of core stability should be considered in high school baseball players, especially in pitchers.

The prevalence and clinical characteristics of sacroiliac joint dysfunction in adolescent baseball players.

BACKGROUND: Sacroiliac joint (SIJ) dysfunction is a potential source of low back pain (LBP) in baseball players, who are more likely to be affected by loading of the SIJ in the throwing motion. However, the prevalence and characteristics of this condition have not been studied thoroughly. This study aimed to investigate the prevalence and clinical characteristics of SIJ dysfunction among high school baseball players. METHODS: Participants comprised 891 high school baseball players who had undergone annual medical evaluations (a self-completed questionnaire and physical examination). The prevalence of SIJ dysfunction and associations with the measurements of the flexibility of the spine and lower extremities such as finger-floor-distance, straight-leg-raising angle, heel-buttock-distance, Thomas test, and passive range of motion of the hip were investigated. RESULTS: Twenty-two of 891 subjects (2.5%) met our criteria for SIJ dysfunction. Twelve subjects (55%) exhibited throwing arm side symptoms more commonly than in the non-throwing arm side (n = 3, 15%) or bilateral side (n = 7, 32%). Previous episodes of LBP were experienced significantly more frequently among subjects with SIJ dysfunction (n = 19, 86.4%) than among those without (n = 501, 57.7%; P = 0.015). The prevalence of present LBP that interfered with play was significantly higher among subjects with SIJ dysfunction (n = 9, 42.9%) than among those without (n = 118, 21.2%; P = 0.038). The prevalence of SIJ dysfunction as a source of LBP was estimated at 7.1% (9 of 127 subjects). After adjustment for associated factors using a logistic regression model, we observed a significant association between a limitation in hip internal rotation on the throwing arm side and SIJ dysfunction (odds ratio 3.11 [1.30-7.71]; P = 0.0109). CONCLUSIONS: According to our criteria, the estimated prevalence of SIJ dysfunction among high school baseball players is 2.5%. There was a significant association between a limitation in hip internal rotation on the throwing arm side and SIJ dysfunction.

Influences of limited flexibility of the lower extremities and occurrence of low back pain in adolescent baseball players: A prospective cohort study.

BACKGROUND: Limited flexibility of the lower extremities, such as hamstring tightness, has long been suggested as a physical risk factor for low back pain among adolescent athletes. However, few prospective cohort studies have examined the direction of causality for this relationship. This prospective cohort study investigated the relationship between limited flexibility of the lower extremities and the occurrence of low back pain among high school baseball players. METHODS: Participants comprised 335 high school baseball players from 43 high school baseball teams who had undergone baseline medical evaluations (a self-completed questionnaire and physical examination). Occurrence of low back pain during a 1-year follow up, and associations with measurements of flexibility of the lower extremities such as straight-leg-raising angle (hamstring tightness), Thomas test (iliopsoas tightness), heel-buttock-distance (quadriceps tightness), and passive range of motion of the hip were investigated. RESULTS: In total, 296 players (88.4%) participated in the 1-year follow-up survey, with 147 of the 296 players (49.7%) reporting the occurrence of low back pain during follow-up. The number of players with low back pain during follow-up peaked in November, then decreased and was lowest in June. After adjusting for factors associated with low back pain using logistic regression modeling, a significant association between hamstring tightness on the non-throwing arm side and low back pain (odds ratio 2.86, 95% confidence interval 1.17-6.94; P = 0.018) was found. CONCLUSIONS: Hamstring tightness on the non-throwing arm side was identified as a potential risk factor for low back pain in high school baseball players. These results may provide guidance in the development of future prevention programs.

The association between clinical symptoms of lumbar spinal stenosis and MRI axial imaging findings.

PURPOSE: In diagnosing lumbar spinal stenosis (LSS), Magnetic Resonance Imaging (MRI) is appropriate to confirm the presence of anatomical stenosis of the spinal canal or compression of the nerve roots. However, it is known that morphological LSS is often present in asymptomatic subjects. There is still controversy about the relationship between anatomical LSS and symptomatic LSS. The aim of this study was to assess the association between qualitative imaging findings on MRI of the lumbar spine and symptomatic LSS. PATIENTS AND METHODS: This was a cross-sectional study of 239 volunteers from an epidemiological survey that included 1,862 participants in total. MRI of the lumbar spine was evaluated in four categories: morphological grading of central stenosis and lateral recess stenosis, presence of the sedimentation sign, and severity of facet joint effusion. The relationship between these morphological evaluations and typical LSS symptoms as assessed by the self-administered, self-reported history questionnaire for lumbar spinal stenosis (LSS-SSHQ) was investigated by multiple logistic regression analysis. RESULTS: The odds ratio of the most severe central stenosis to no stenosis was 15.5 (95%CI: 1.4-164.9). Only the most severe central stenosis was associated with typical LSS symptoms, but not all cases with typical LSS symptoms were due to severe central stenosis. CONCLUSION: Extreme severe central stenosis was strongly related to typical LSS symptoms. However, although subjects with severe central stenosis showed symptoms suggestive of LSS, these subjects did not always show typical LSS symptoms.

Association Between Musculoskeletal Pain and Psychological Stress Responses in High School Baseball Players: A Cross-sectional Study.

BACKGROUND: Musculoskeletal pain could represent a psychological stressor in adolescent athletes. However, few epidemiological studies have investigated this association. PURPOSE: To assess the relationship between musculoskeletal pain (shoulder, elbow, wrist, and low back) and psychological stress responses in high school baseball players. STUDY DESIGN: Cross-sectional study. METHODS: Participants comprised male Japanese high school baseball players who had completed a questionnaire as part of their annual medical evaluation in 2016. Experiences of shoulder, elbow, wrist, and low back pain during the previous season were investigated. Pain severity was graded as 1 (mild, playing without interference), 2 (moderate, playing with interference), or 3 (severe, could not play because of pain). The Stress Response Scale-18 was used to measure stress response: low, medium, rather high, and high. Prevalence rates of shoulder, elbow, wrist, and low back pain and their association with psychological stress responses were investigated using univariate and multivariable analyses. RESULTS: A total of 944 players (223 pitchers and 721 fielders) were included in this study. Their mean age was 16.1 ± 0.6 years, and 66% were high school juniors, while 33.6% were seniors. In pitchers, the prevalence rates during the previous year of severe (grade 3) interference with playing because of elbow, shoulder, wrist, and low back pain were 21.5% (n = 48), 19.3% (n = 43), 3.6% (n = 8), and 18.4% (n = 41), respectively, whereas in fielders, the respective prevalence rates were 17.1% (n = 123), 17.9% (n = 129), 6.7% (n = 48), and 19.3% (n = 139). After adjusting for confounding factors (playing on a top-performing team, high school grade level, and all other sites of musculoskeletal pain), the authors found significant associations in pitchers between severe experiences of elbow pain and low back pain and medium to high psychological stress responses (odds ratio, 2.64 [95% CI, 1.32-5.39], P = .006 and odds ratio, 2.32 [95% CI, 1.12-4.89], P = .024, respectively). No significant associations were seen between musculoskeletal pain and psychological stress responses in fielders. CONCLUSION: In the current study, elbow and low back pain were associated with stronger psychological stress responses compared with other musculoskeletal pain in high school baseball pitchers.

Dose-response relationship between spino-pelvic alignment determined by sagittal modifiers and back pain-specific quality of life.

PURPOSE: To determine whether abnormalities of the sagittal modifiers (SMs) of the Scoliosis Research Society (SRS)-Schwab classification truly reflect back pain (BP)-specific quality of life (QOL), it is necessary to examine their dose-response relationships and to determine clinically impactful thresholds for declines in BP-specific QOL. This study aimed to analyse the continuous dose-response relationship between each SM and BP-specific QOL. METHODS: This cross-sectional study, using data from a Japanese population-based cohort study, included 519 community-dwelling residents aged ≥ 50 years who participated in the annual health examination. The participants completed the Roland-Morris Disability Questionnaire (RDQ) on BP-specific QOL. Spino-pelvic alignment based on SMs was assessed by whole-spine X-ray examinations. We fitted general linear models with or without nonlinear terms to estimate the dose-response relationship between each SM and BP-specific QOL. RESULTS: Pelvic tilt, pelvic incidence minus lumbar lordosis (PI-LL), and sagittal vertical axis showed dose-response relationships with BP-specific QOL measured as the RDQ score. PI-LL was most likely to predict a minimally clinically important RDQ score when its value exceeded the 90th percentile. A nonlinear relationship between PI-LL and the BP-specific QOL score was found. RDQ increased when PI-LL exceeded 10°. CONCLUSION: PI-LL might be the most sensitive of the three modifiers of the SRS-Schwab classification for determining BP-specific QOL. Moreover, BP-specific QOL worsens rapidly when the compensatory mechanism against malalignment exceeds a critical value. Therefore, we suggest that traditional classifications and surgical strategies should be re-examined regarding the dose-dependent abnormalities of the SMs to develop a more reliable classification strategy.