Number of contiguous vertebral cross-links in the spine indicates bone formation: a cross-sectional study.

BACKGROUND: As an indicator to evaluate the risk of fracture in diffuse idiopathic skeletal hyperostosis, the maximum number of vertebral bodies' bone cross-linked with contiguous adjacent vertebrae (max VB) was developed. This study retrospectively investigates the relationship between max VB, bone mineral density (BMD), and bone metabolic markers (BMM). METHODS: In this cross-sectional study (from April 2010 to January 2022), males (n = 114) with various max VB from the thoracic vertebra to the sacrum, measured using computed tomography scans, were selected to assess femur BMD and BMM. The association of max VB with the total type I procollagen N-terminal propeptide (P1NP), tartrate-resistant acid phosphatase 5b (TRACP-5b), and bone turnover ratio (BTR = TRACP-5b/P1NP) as well as its relationship with femur BMD with P1NP and TRACP-5b, were investigated. Furthermore, the relationship between P1NP and TRACP-5b was investigated. RESULTS: P1NP increased in proportion to max VB and TRACP-5b increased in proportion to P1NP. Moreover, BTR was inversely proportional to max VB. Finally, femur BMD was inversely proportional to P1NP and TRACP-5b. CONCLUSION: As max VB increased with P1NP-a potential osteogenesis indicator-and BTR was inversely proportional to max VB with compensatory TRACP-5b increase, max VB can be considered as a possible predictor of bone fusion.

Maximum number of bone cross-linked vertebrae: an index for BMD in diffuse idiopathic skeletal hyperostosis.

INTRODUCTION: The maximum number of vertebral bodies with bony bridges between adjacent vertebrae (max VB) helps assess the risk of fracture in diffuse idiopathic skeletal hyperostosis (DISH). In addition to max VB, the maximum thickness of bone cross-bridges (max TB) may be an index of bone mineral density (BMD). Therefore, this study investigated the relationship among max VB, max TB, and BMD. MATERIALS AND METHODS: The participants in this cross-sectional study were male patients (n = 123) with various max VB from the thoracic vertebrae to the sacrum without sacroiliac ankylosis. The participants were grouped by max VB. For example, a group with max VB from 4 to 8 would be listed as max VB (4-8). The relation between femur proximal BMD and mean max TB and max VB was assessed. Femur proximal BMD was then compared after adjusting for confounding factors. RESULTS: The results indicated that max VB was correlated with femur proximal BMD in max VB (0-8) and max VB (9-18) groups. The mean max TB was correlated only with femur proximal BMD in max VB (0-8). After adjusting, max VB (4-8) showed a significantly higher femur proximal BMD than max VB (0-3) and max VB (9-18). CONCLUSION: Femur proximal BMD and mean max TB showed different trends after max VB = 9, which suggests that max VB is an index of BMD, and that DISH has at least two possible populations in terms of BMD and bone cross-link thickness.

Surgical Outcomes of Selective Laminectomy for Patients With Cervical Kyphosis: A Retrospective Study of 379 Cases.

STUDY DESIGN: A retrospective study. OBJECTIVES: This study aimed to investigate the impact of cervical kyphosis on patients with cervical spondylotic myelopathy (CSM) following selective laminectomy (SL) regarding posterior spinal cord shift (PSS), and a number of SLs. METHODS: We evaluated 379 patients with CSM after SL. The patients with kyphosis (group K) were compared with those without kyphosis (group L). Moreover, groups K and L were divided into subgroups KS and KL (SLs ≤ 2) and LS and LL (SLs ≥ 3), respectively, and analyzed. Receiver operating characteristic (ROC) curve analysis was performed to determine the cut-off value of the C2-C7 angle for satisfactory surgical outcomes, which was defined as a Japanese Orthopaedic Association (JOA) recovery rate of ≥50% in group KS. RESULTS: The average PSS (mm) in group K was smaller than that in group L (.8 vs 1.4; P < .01), but the JOA recovery rate was comparable between the 2 groups. Meanwhile, the mean PSS and JOA recovery rate (%) in group KS was lower than those in group KL, respectively (.3 vs 1.0; P < .01, 35.1 vs 52.3; P = .047). Moreover, the average PSS of group KS (.6) was smaller than those of other subgroups ( < .01). In addition, the ROC curve analysis showed that the C2-C7 angle of -14.5° could predict satisfactory surgical outcomes in group KS. CONCLUSION: Selective laminectomy is not contraindicated for patients with kyphosis, but a larger number of SLs may be indicated for the patients with C2-C7 angles of ≤ -14.5°.

Assessment of the Necessity of Osteoporosis Treatment for Patients with Low Bone Density in Diffuse Idiopathic Skeletal Hyperostosis.

Introduction: Although patients with diffuse idiopathic skeletal hyperostosis (DISH) do not have low bone density, it is a risk factor for spine fractures associated with DISH. We investigated the characteristics and bone metabolism markers of patients with DISH having low bone density to assess whether osteoporosis medication is necessary to prevent fractures. Methods: A cross-sectional study was conducted between April 1, 2008, and March 31, 2019. The 86 patients included were divided into two groups according to their T-scores-one group had low bone density and DISH, and the other group did not. Group A (T-score≤-1) and B (T-score>-1) data were adjusted for confounding factors and compared for differences in age, body weight, maximum number of vertebral bodies with bony bridges between adjacent vertebrae (max VB), and previous history (hypertension, malignant tumors, diabetes mellitus, cardiac diseases, chronic renal failure, and spinal fractures). In Group A, multiple linear regression was used to investigate relationships among max VB, femur bone mineral density (BMD), total type I procollagen N-terminal propeptide (P1NP), and tartrate-resistant acid phosphatase 5b (TRACP-5b). Results: Group A had 36, and Group B had 50 male patients with DISH. Patients in Group B were heavier than those in Group A. The mean femur BMD in Group A was age-appropriate, and that in Group B was higher than the age-appropriate femur BMD. The mean values of P1NP and TRACP-5b were within the normal range. Max VB was positively correlated with total P1NP in Group A. Total P1NP was significantly and positively correlated with TRACP-5b. Conclusions: The DISH group with a T-score of ≤-1 was age-appropriate. The group with a T-score of >-1 had higher BMD because of their higher body weight. The group with a T-score of ≤-1 had good bone metabolism and did not require aggressive osteoporosis treatment.

Association of Continuous Vertebral Bone Bridges and Bone Mineral Density with the Fracture Risk in Patients with Diffuse Idiopathic Skeletal Hyperostosis.

STUDY DESIGN: Cross-sectional study. PURPOSE: To examine whether the number of continuous vertebral bone bridges and bone mineral density (BMD) influence the fracture risk in diffuse idiopathic skeletal hyperostosis (DISH) patients. OVERVIEW OF LITERATURE: Bone bridges connecting through the intervertebral body in DISH create long lever arms that can increase the risk of fractures from minor trauma. DISH patients have a BMD that is higher than or comparable to those of age-matched healthy subjects. METHODS: We examined the computed tomography scans from the thoracic vertebra to the sacrum used to diagnose DISH in 140 patients (98 men and 42 women; average age, 78.6 years). We compared patients who did (n=52) and did not have (n=88) fractures at the continuous vertebral bodies fused by bone bridges. The relationship between the vertebral fractures and the maximum number of vertebrae that are bony cross-linked with contiguous adjacent vertebrae (max VB) from the thoracic vertebra to the sacrum or from the lumbar vertebra to the sacrum and proximal femur BMD were analyzed using a logistic regression model. RESULTS: We found that after adjusting for the confounding factors, higher max VB, both from the thoracic vertebrae to the sacrum and the lumbar vertebrae to the sacrum, was associated with a higher risk of vertebral fractures. This difference was statistically significant. The risk was higher when only the lumbar vertebrae to the sacrum was considered (thoracic vertebrae to the sacrum: odds ratio, 1.21; p<0.05; lumbar vertebrae to the sacrum: odds ratio, 2.78; p<0.01). Moreover, low proximal femur BMD in DISH patients raises the fracture risk (odds ratio, 0.47; p<0.01). CONCLUSIONS: Many continuous vertebral bone bridges, especially those that extend to the lumbar spine and low proximal femur BMD, are risk factors for fracture in DISH patients.

Femur Bone Mineral Density and Pentosidine Level Distinguish Ankylosing Spinal Disorder Patients with and without Sacroiliac Ankylosis.

INTRODUCTION: When spinal fracture occurred in ankylosing spinal disorder (ASD) patients, it is important to evaluate not only the long lever arm but also bone density and bone quality for the determination of treatment strategies. This case-controlled study examined bone mineral density (BMD), bone metabolism markers, and pentosidine levels in patients with ASD. METHODS: Subjects with bridging of minimum four contiguous vertebral bodies were classified into ASD group and the rest into non-ASD group. The former was further divided into two subgroups based on the presence/absence of sacroiliac joint ankylosis (SJA). We compared BMD, bone metabolism markers, and pentosidine levels in these groups. RESULTS: The BMD T and Z scores of the femur proximal extremity were lower in the ASD with SJA group than those in the ASD without SJA group. When groups were matched for age, weight, and eGFR, compared with the non-ASD group, the ASD with SJA group had lower BMD of the lumbar spine and femur proximal extremity and the ASD without SJA group had significantly higher BMDs of the lumbar spine and femur proximal extremity. After matching, the ASD without SJA group showed a significantly higher pentosidine level than the non-ASD group. CONCLUSIONS: Patients with SJA have low femur proximal extremity BMD, whereas those with ASD without SJA have a higher BMD of the femur proximal extremity with high pentosidine level. Investigating the presence or absence of SJA is important for the determination of treatment strategies in fractured ASD patients.

Vascular Complication after Collagenase Injection and Manipulation for Dupuytren's Contracture: A Case Report.

A case of a vascular complication after collagenase injection and manipulation for Dupuytren's contracture in a 57-year-old Japanese man is described. The patient presented with a 10-year history of worsening primary Dupuytren's contracture. The metacarpophalangeal joint of his left little finger had a flexion contracture of 40° and was treated by collagenase injection. When the patient returned to our hospital for manipulation 24 hours later, however, his left little finger was almost completely improved because he hit his finger on the car's gear lever. Then, 9 months after collagenase injection, in the first winter, he complained of a painful and pale left little finger occurring a few times a day, lasting for about 10 minutes. Now, two years after collagenase injection, the episodes of Raynaud's phenomenon remain. Although Raynaud's phenomenon after collagenase injection and manipulation for Dupuytren's contracture is considered rare, it is a complication to be noted.

Association of Susceptibility Genes for Adolescent Idiopathic Scoliosis and Intervertebral Disc Degeneration With Adult Spinal Deformity.

STUDY DESIGN: Genetic case-control study of single nucleotide polymorphisms (SNPs). OBJECTIVE: To examine the association of previously reported susceptibility genes for adolescent idiopathic scoliosis (AIS) and intervertebral disc (IVD) degeneration with adult spinal deformity (ASD). SUMMARY OF BACKGROUND DATA: ASD is a spinal deformity that develops and progresses with age. Its etiology is unclear. Several ASD susceptibility genes were recently reported using a candidate gene approach; however, the sample sizes were small and associations with ASD development were not determined. METHODS: ASD was defined as structural scoliosis with a Cobb angle more than 15° on standing radiographs, taken of patients at age 40 to 75 years in this study. Subjects in whom scoliosis was diagnosed before age 20 were excluded. We recruited 356 Japanese ASD subjects and 3341 healthy controls for case-control association studies of previously reported SNPs. We genotyped four known AIS-associated SNPs (rs11190870 in LBX1, rs6570507 in GPR126, rs10738445 in BNC2, and rs6137473 in PAX1) and three IVD degeneration-associated SNPs (rs1245582 in CHST3, rs2073711 in CILP, and rs1676486 in COL11A1) by the Invader assay. RESULTS: Among the AIS-associated SNPs, rs11190870 and rs6137473 showed strong and nominal associations with ASD (P = 1.44 × 10, 1.00 × 10, respectively). Of the IVD degeneration-associated SNPs, rs1245582 and rs2073711 showed no association with ASD, while rs1676486 showed a nominal association (P = 1.10 × 10). In a subgroup analysis, rs11190870 was significantly associated with a Cobb angle more than 20° in the minor thoracic curve (P = 1.44 × 10) and with a left convex lumbar curve (P = 6.70 × 10), and nominally associated with an apical vertebra higher than L1 (P = 1.80 × 10). CONCLUSION: rs11190870 in LBX1, a strong susceptibility SNP for AIS, may also be a susceptibility SNP for ASD. Thus, ASD and AIS may share a common genetic background. LEVEL OF EVIDENCE: 4.