Surgical treatment for persistent second carpometacarpal joint pain.

The purposes of this study were to demonstrate the clinical characteristics of patients with persistent second carpometacarpal (CMC) joint pain without bony abnormalities known as the carpal boss, and to assess the clinical efficacy of surgical stabilization of the second CMC joint. Eleven patients had persistent wrist pain with characteristic symptoms, including tenderness over the second CMC joint, increased symptoms when the involved hand was placed on the ground or gripped strongly with the involved hand, a positive metacarpal stress test and temporary pain relief with the intra-articular injection of the lidocaine. The patients underwent arthrodesis of the second CMC joint. All cases showed radiologically confirmed fusion of the second CMC joint. At the final followup examination, 10 of 11 patients resulted in satisfactory clinical outcomes, excepting one patient with remnant pain and restricted range of wrist motions. This report highlights the importance of conducting a careful assessment of patients who present with persistent second CMC joint pain without the bony abnormalities, such as carpal bossing. Surgery to stabilize the second CMC joint may be an option to improve their symptoms when conservative treatment fails.

Ultrasonographic Measurement of the Median Nerve Transverse Diameter at the Wrist for Diagnosing Carpal Tunnel Syndrome.

Background: Ultrasonographically measuring the median nerve cross-sectional area (MN-CSA) is a useful and complementary method for diagnosing carpal tunnel syndrome (CTS). This study investigated the usefulness of the median nerve transverse diameter (MN-TD) as a simpler and easier technique than MN-CSA for diagnosing CTS severity. Methods: We examined 145 hands from 101 patients with CTS and 114 age- and gender-matched control hands. Based on the electrodiagnostic findings, the severity of CTS was divided into minimal, mild, moderate, severe and extreme. An ultrasonographic assessment of MN-TD and MN-CSA was performed to measure the maximal values around the carpal tunnel inlet level. The values were assessed for comparisons between the CTS and control groups and for the evaluation of differences by CTS severity. Results: The ultrasonographic measurements of MN-TD and MN-CSA were significantly increased in the CTS group compared to the normal group. Furthermore, both measurements significantly increased with increasing CTS severity. A receiver operating characteristic curve (ROC) analysis showed that participants with MN-TD > 7.2 mm had CTS with 88% specificity and 74% sensitivity, and those with MN-CSA > 12.0 mm2 had CTS with 86% specificity and 84% sensitivity. Conclusions: Ultrasonographic measurement for MN-TD may be useful for diagnosing CTS patients and predicting the severity.

Efficacy of collagenase Clostridium histolyticum injection for Dupuytren's contracture in East-Asian population.

BACKGROUND: Treatment with injection of collagenase Clostridium histolyticum (CCH) has been recognized as an effective option for the Dupuytren's contracture (DC) in Europe and North America. However, there are no studies describing mid-term efficacy of CCH treatment in East-Asian population. The purpose of this study was to assess 2-year outcomes following CCH treatment in Japanese patients. METHODS: Twenty hands (28 joints) from 18 DC patients underwent CCH injection with manipulation according to the product specifications with 2-year follow-up. Patients were assessed for extension deficit on treated metacarpophalangeal (MCP) and/or proximal interphalangeal (PIP) joints before treatment, at 4 weeks and 2 years after the treatment. RESULTS: At 4 weeks after CCH treatment, contracture of treated joints significantly improved from the mean extension deficit of 45° before treatment to 3° for MCP joints, and from 41° to 14° for PIP joints (P < 0.001, <0.001, respectively). Improved contracture was maintained with 4° and 23° at 2 years after CCH treatment (P < 0.001, <0.05, respectively). Successful correction defined as ≤ 5° extension deficit was obtained in 14/16 MCP and 5/12 PIP joints at 4 weeks; of these, 11 MCP and 1 PIP joints maintained the corrected range of motion at 2-year follow-up. CONCLUSION: CCH treatment could be a useful option to improve contracture in Japanese patients. During 2-year follow-up, this treatment could provide comparable effect durability to previous studies from Western countries. Moreover, our results support the evidence that better correction of the contracture can be obtained in the MCP joints than PIP joints after CCH treatment.

Influence of living environments and working status on low back pain for survivors of the Great East Japan Earthquake.

BACKGROUND: The Great East Japan Earthquake and devastating Tsunami caused irreparable damage on the northeastern coast of Japan. This study aimed to examine the influencing factors of "Living environment" and "Working status" on low back pain for the survivors of the earthquake evaluated by a self-report questionnaire. METHODS: Between 2011 and 2013, survivors replied to the self-report questionnaire, and 986 people consented to join this study. The living environment was divided into 3 categories (1. Living in the same house as before the earthquake, 2. Living in a safe shelter or temporary small house, 3. Living in a house of relatives or apartment house) and working status was divided into 5 categories (1. Unemployed before the earthquake, 2. Unemployed after the earthquake, 3. Decrease in income, 4. Different occupation after the earthquake, 5. The same occupation as before the earthquake). Age, gender, living areas, past history of arthritis, arthropathy, osteoporosis, sleep disturbance, psychological distress, and economic status were considered as confounding factors. Generalized estimating regression models with logit link function were used because outcome variables are repeatedly measured and binomial. We evaluated the correlation between the presence/severity of low back pain over time and housing status/working status at 1 year after the earthquake. RESULTS: There were no significant differences between age, gender, living areas, working status, or living environment before or after the earthquake. There was no significant difference in the risk of having low back pain in living environment or gender. There was significant difference in the risk of having low back pain in those with "Decrease in income" (OR = 1.93, 95% CI = 1.23-3.03) and "The same occupation as before the earthquake" (OR = 1.67, 95% CI = 1.1-2.52). CONCLUSIONS: Though living environment has little effect, "Decrease in income" and "The same occupation as before the earthquake" have strong influences on low back pain.

Quantitative in vivo biocompatibility of new ultralow-nickel cobalt-chromium-molybdenum alloys.

Nickel (Ni) eluted from metallic biomaterials is widely accepted as a major cause of allergies and inflammation. To improve the safety of cobalt-chromium-molybdenum (Co-Cr-Mo) alloy implants, new ultralow-Ni Co-Cr-Mo alloys with and without zirconium (Zr) have been developed, with Ni contents of less than 0.01%. In the present study, we investigated the biocompatibility of these new alloys in vivo by subcutaneously implanting pure Ni, conventional Co-Cr-Mo, ultralow-Ni Co-Cr-Mo, and ultralow-Ni Co-Cr-Mo with Zr wires into the dorsal sides of mice. After 3 and 7 days, tissues around the wire were excised, and inflammation; the expression of IL-1ß, IL-6, and TNF-α; and Ni, Co, Cr, and Mo ion release were analyzed using histological analyses, qRT-PCR, and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Significantly larger amounts of Ni eluted from pure Ni wires than from the other wires, and the degree of inflammation depended on the amount of eluted Ni. Although no significant differences in inflammatory reactions were identified among new alloys and conventional Co-Cr-Mo alloys in histological and qRT-PCR analyses, ICP-MS analysis revealed that Ni ion elution from ultralow-Ni Co-Cr-Mo alloys with and without Zr was significantly lower than from conventional Co-Cr-Mo alloys. Our study, suggests that the present ultralow-Ni Co-Cr-Mo alloys with and without Zr have greater safety and utility than conventional Co-Cr-Mo alloys. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1505-1513, 2016.

Decreased elastic fibers and increased proteoglycans in the ligamentum flavum of patients with lumbar spinal canal stenosis.

Elastic fibers and proteoglycans are major components of the extracellular matrix and their changes have been reported in some pathological conditions. Further, recent studies have indicated that some glycosaminoglycans and proteoglycans inhibit elastic fiber assembly. The purpose of this study was to investigate changes of the elastic fibers and proteoglycans in the ligamentum flavum and analyze their relationships to thickening of the ligamentum flavum from lumbar spinal canal stenosis (LSCS). Ligamentum flavum samples were collected from 20 patients with LSCS (thickened flavum group) and 10 patients with lumbar disc herniation (non-thickened flavum group) as a control. Elastica-Masson staining and alcian blue staining were used to compare the relationship between the changes in the elastic fibers and proteoglycans. Gene and protein expressions of the elastic fibers and proteoglycans were analyzed by quantitative reverse transcription polymerase chain reaction and immunohistochemistry. Histological changes indicated that proteoglycans mainly increased on the dorsal side of the ligamentum flavum in accordance with the decreased elastic fibers in the thickened flavum group. The gene and protein expressions of fibrillin-2 and DANCE were significantly lower and decorin, lumican, osteoglycin, and versican were significantly higher in the thickened flavum group. Our study shows that elastic fibers decrease and proteoglycans increase in the thickened ligamentum flavum. Decreased gene expression of elastogenesis and disrupted elastic fiber assembly caused by increased proteoglycans may lead to a loss of elasticity in the thickened ligamentum flavum. Decreased elasticity may cause buckling of the tissue, which leads to thickening of the ligamentum flavum. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1241-1247, 2016.

Preventing effects of joint contracture by high molecular weight hyaluronan injections in a rat immobilized knee model.

PURPOSE: To elucidate preventive effects of high molecular weight hyaluronan (HMWHA) on the joint capsule of immobilized knees in rats. MATERIALS AND METHODS: Unilateral knee joints of rats were immobilized with an internal fixator. Either 50 µl of HMWHA (Im-HA group) or 50 µl of saline (control group) was administered intra-articularly once a week after surgery. Sagittal sections were prepared from the medial midcondylar region of the knee joints and assessed by histological, histomorphometric, and immunohistochemical methods. Gene expressions related to inflammation, fibrotic conditions, and hypoxia were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Tissue elasticity of the capsule from both groups was examined using a scanning acoustic microscope (SAM). RESULTS: CD68 positive cells decreased in adhesion areas of the synovial membrane after 1 week in both groups. The length of the superficial layer in the synovial membrane of the Im-HA group was significantly longer than those in the control group over a period of 4 to 8 weeks with significantly small numbers of CD68 positive cells. The gene expressions of IL-6, IL-1ß, TGF-ß, CTGF, COL1a1, COL3a1, SPARC, and HIF1-α were significantly lower in the Im-HA group compared to those in the control group. The sound speed of the anterior and posterior synovial membrane increased significantly (a reduction in elasticity) in the control group compared to those in the Im-HA group during weeks 1 to 4. CONCLUSIONS: This study demonstrated that HMWHA injections suppressed inflammatory, fibrotic, and hypoxic conditions observed in the immobilized joint capsule.

Chondrogenic and fibrotic process in the ligamentum flavum of patients with lumbar spinal canal stenosis.

STUDY DESIGN: A histological, biological, and immunohisto-chemical study of human lumbar ligamentum flavum. OBJECTIVE: To analyze changes in the hypertrophied ligamentum flavum and clarify their etiology. SUMMARY OF BACKGROUND DATA: Hypertrophy of the ligamentum flavum has been considered a major contributor to the development of lumbar spinal canal stenosis (LSCS). Although previous studies have reported some factors related to ligamentum flavum hypertrophy, its etiology is still unclear. METHODS: Ligamentum flavum samples were collected from 20 patients with LSCS (LSCS group) and 10 patients with lumbar disc herniation (LDH group) as a control. The thickness of the ligamentum flavum was measured histologically. The amounts of elastic fibers and proteoglycans were assessed by Elastica-Masson staining and alcian blue staining, respectively. Gene and protein expressions related to fibrosis, inflammation, and chondrogenesis were analyzed by quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. The total genes of the 2 groups were compared by DNA microarray analysis. RESULTS: The ligamentum flavum was significantly thicker in the LSCS group, which had a smaller amount of elastic fibers and a larger amount of proteoglycans. The gene expression related to fibrosis was significantly higher in the LSCS group; however, the immunoreactivities of collagen types I and III were weaker on the dorsal side of the ligamentum flavum in the LSCS group. The gene expression related to chondrogenesis and proteoglycan synthesis was significantly higher in the LSCS group. There was no significant difference in the gene expression related to inflammation between the 2 groups. CONCLUSION: Synthesis of the collagenous fibers and degradation of the elastic and collagenous fibers are both accelerated in the ligamentum flavum of patient with LSCS, which may be the reason for hypertrophy of the tissue. In addition, chondrogenesis and proteoglycan synthesis may have critical roles in the pathogenesis of the ligamentum flavum hypertrophy. LEVEL OF EVIDENCE: 5.

Simultaneous evaluation of articular cartilage and subchondral bone from immobilized knee in rats by photoacoustic imaging system.

BACKGROUND: Osteoarthritis is not only a disease of articular cartilage, but also of subchondral bone. It is difficult for ultrasound to evaluate subchondral bone because of permeability. This study aimed to evaluate sequential osteoarthritic changes of articular cartilage and subchondral bone from immobilized knees in rats with a photoacoustic (PA) imaging system. METHODS: The unilateral knee joints of adult male rats were immobilized with an internal fixator (IM group) for 4 and 8 weeks. Sham operated animals had holes drilled in the femur and tibia and screws inserted without a plate (control group). A whole proximal third of the tibia was obtained. The specimens were immersed in normal saline and scanned by the PA imaging system, which can create both ultrasound (US) and PA imaging. After the scanning, specimens were fixed with paraformaldehyde, decalcified and embedded in paraffin. Thinly sliced tissues were prepared for histological evaluation. PA signals from the articular cartilage and subchondral bone were independently evaluated. RESULTS: Gross observations showed that fibrillation occurred in the superficial layers and permeability of the articular cartilage increased. Histological observations showed that the articular cartilage became thicker and the bone marrow space expanded during immobilization. US images by the PA imaging system could evaluate the articular cartilage. PA signals from the articular cartilage and subchondral bone increased with the duration of immobilization and the difference, compared to the control group, was significant. CONCLUSIONS: The PA imaging system could evaluate articular cartilage and subchondral bone simultaneously.

Thoracic radiculopathy caused by ossification of the ligamentum flavum.

Thoracic ossification of the ligamentum flavum (OLF) has been widely recognized as a main cause of thoracic myelopathy in Asia, particularly in Japan. However, thoracic OLF rarely causes radiculopathy. We report a rare case of thoracic radiculopathy caused by OLF. A 67-year-old male presented with a chief complaint of back pain radiating to the right of the abdomen. Neurological examination revealed mild sensory deficit at the right side of the abdomen at the T9-10 level. Magnetic resonance imaging and computed tomography demonstrated OLF at the right T9-10 level. Thoracic radiculopathy caused by OLF was suspected. Because conservative treatment was not effective to this lesion, surgical intervention was performed, and the pain disappeared immediately after the operation. Thoracic OLF rarely causes radiculopathy, but it should be considered as a differential diagnosis of thoracic radicular pain. When conservative treatment is not effective in this lesion, surgical treatment should be considered.