Determination of reference intervals for fluid analysis and cytologic evaluation variables in synovial fluid samples obtained from carpal and tarsal joints in commercial nonlame growing swine

OBJECTIVE To determine reference intervals for total nucleated cell count, total protein concentration, pH, RBC count, and percentages of neutrophils, lymphocytes, and large mononuclear cells in synovial fluid samples (SFSs) obtained from the carpal and tarsal joints of healthy swine. ANIMALS 54 healthy commercial finisher pigs that had no evidence of lameness or gross joint swelling. PROCEDURES Each pig was anesthetized, and SFSs were collected from 1 carpal and 1 tarsal joint for fluid analysis, cytologic evaluation, bacterial culture, and PCR analyses for common swine joint pathogens. Each pig was euthanized after SFS collection, and synovial tissue samples were collected for histologic assessment. If necessary, postmortem SFSs were collected. RESULTS Overall, 37 of 50 tarsal and 46 of 53 carpal SFSs met inclusion criteria of sufficient volume, no gross blood contamination, and negative results of bacterial culture and PCR analyses, and were from joints with histologically normal synovial tissues. For the carpal and tarsal joints, upper reference limits were as follows: total nucleated cell count, 3,281 cells/μL and 2,368 cells/μL, respectively; total protein concentration, 3.6 g/dL and 3.6 g/dL, respectively; pH, 7.2 and 7.0, respectively; RBC count, 0.8 × 10⁶ cells/μL and 0.1 × 10⁶ cells/μL, respectively; and percentage of neutrophils, 46.5% and 33.7%, respectively; percentage of lymphocytes, 40.6% and 56.3%, respectively; and percentage of large mononuclear cells, 92.0% and 95.3%, respectively. CONCLUSIONS AND CLINICAL RELEVANCE Results have provided reference intervals for selected variables in SFSs obtained from the carpal and the tarsal joints of healthy swine, which should be useful in diagnostic investigations of swine lameness and arthritis.

Automatic bone age assessment for young children from newborn to 7-year-old using carpal bones

A computer-aided-diagnosis (CAD) method has been previously developed based on features extracted from phalangeal regions of interest (ROI) in a digital hand atlas, which can assess bone age of children from ages 7 to 18 accurately. Therefore, in order to assess the bone age of children in younger ages, the inclusion of carpal bones is necessary. However, due to various factors including the uncertain number of bones appearing, non-uniformity of soft tissue, low contrast between the bony structure and soft tissue, automatic segmentation and identification of carpal bone boundaries is an extremely challenging task. Past research works on carpal bone segmentation were performed utilizing dynamic thresholding. However, due to the limitation of the segmentation algorithm, carpal bones have not been taken into consideration in the bone age assessment procedure. In this paper, we developed and implemented a knowledge-based method for fully automatic carpal bone segmentation and morphological feature analysis. Fuzzy classification was then used to assess the bone age based on the selected features. This method has been successfully applied on all cases in which carpal bones have not overlapped. CAD results of total about 205 cases from the digital hand atlas were evaluated against subject chronological age as well as readings of two radiologists. It was found that the carpal ROI provides reliable information in determining the bone age for young children from newborn to 7-year-old.

Connexin 40, a target of transcription factor Tbx5, patterns wrist, digits, and sternum

Haploinsufficiency of T-box transcription factor 5 (TBX5) causes human Holt-Oram syndrome (HOS), a developmental disorder characterized by skeletal and heart malformations. Mice carrying a Tbx5 null allele (Tbx5(+/Delta)) have malformations in digits, wrists, and sternum joints, regions where Tbx5 is expressed. We demonstrate that mice deficient in connexin 40 (Cx40), a Tbx5-regulated gap junction component, shared axial and appendicular skeletal malformations with Tbx5(+/Delta) mice. Although no role in skeleton patterning has been described for gap junctions, we demonstrate here that Cx40 is involved in formation of specific joints, as well as bone shape. Even a 50% reduction in either Tbx5 or Cx40 produces bone abnormalities, demonstrating their crucial control over skeletal development. Further, we demonstrate that Tbx5 exerts in part its key regulatory role in bone growth and maturation by controlling via Cx40 the expression of Sox9 (a transcription factor essential for chondrogenesis and skeleton growth). Our study strongly suggests that Cx40 deficiency accounts for many skeletal malformations in HOS and that Tbx5 regulation of Cx40 plays a critical role in the exquisite developmental patterning of the forelimbs and sternum.

The effects of reduced oxygen tension on cell proliferation and matrix synthesis in synovium and tendon explants from the rabbit carpal tunnel: an experimental study in vitro

Local ischemia may play an important role in the development of tendon degeneration as well as entrapment neuropathies. In order to investigate the cellular effects of hypoxia on tendon and synovial tissue from the carpal canal, dose response effects of oxygen on cell proliferation and synthesis of matrix components were examined in segments of synovial and flexor digitorum profundus tendon from the carpal tunnel of rabbits during short term culture. Explants were incubated in airtight containers flushed with either 0%, 1%, 3%, 20% O2 plus 2% CO2 and N2 to balance and labeled with either 3H-thymidine or 3H-proline and 35S-sulfate. Cell proliferation was significantly inhibited by hypoxia in synovium but not in tendon (P = 0.03). In parallel, the synthesis of non-collagenous proteins was significantly reduced in synovium but not in tendon (P = 0.006). In both tissues hypoxia significantly inhibited collagen synthesis. On the other hand, hypoxia had no significant effect on the synthesis of new proteoglycans as determined by 35S-sulfate incorporation. Hypoxia can inhibit cell proliferation and alter synthesis of matrix components in synovial tissue, but may only have minor effects on non-collagen protein synthesis in tendon explants from the carpal canal of rabbit forepaws.

Experimental osteonecrosis of the lunate. Revascularization may cause collapse

Is lunate collapse in Kienböck's disease a consequence of spontaneous revascularization, leading to focal osteolysis? A literature review of osteonecrosis in other locations such as the femoral head and bone allografts showed clearly that the loss of mechanical integrity is due to cellular processes which follow the spontaneous restoration of blood supply. We found no evidence in the literature that the lunate has been shown to be avascular at the time of collapse. On the contrary, increased osteoclastic activity has been reported. We excised and reimplanted the lunate in two monkeys, and found spontaneous revascularization, leading to increased osteoblastic activity. Other parts of the bone were destroyed by osteoclasts, leading to collapse. This histological example suggests that it may be possible to make an analogy with osteonecrosis in other locations. Thus, changes on plain radiography may indicate that the bone is revascularized spontaneously. Before performing operative revascularization of the lunate, one should consider that revascularization is a probable cause for collapse.

[Status and frequency of local juxta-articular demineralization and erosion in the wrist area in the early phase of chronic polyarthritis. Results based on 3-dimensional soft x-ray pictures]

In early rheumatoid arthritis the location and incidence of localized juxta-articular demineralizations and erosions were investigated at 53 points of the wrist. On the level of the metacarpal bases, the distal and proximal row of the carpal bones more changes are seen in the oblique vd. and the lateral view than in the dv. view. At the distal bones of the forearm more changes are seen at the radius than at the ulnar styloid. The most often changes at all occur at the volar middle third of the triquetrum in the oblique view and at the distal volar articular facet of the scaphoid in the lateral view. Close relations between localized juxta-articular demineralizations and erosions do not exist. If the early bone changes at the wrist in rheumatoid arthritis are to be detected additional oblique and lateral view are prerequisite.

Advantage of hand bone calcium content measurement by local neutron activation analysis for following up hemodialysis patients

Hand bone calcium content [Ca] has been measured by local neutron analysis in hemodialyzed patients free of signs of osteomalacia before and 6-12 months after treatment with vitamin D metabolites, and it has been compared to some iliac bone histomorphometric parameters. With 1,25-(OH)2D3 alone, [Ca] increases significantly at the 6th month of treatment (p less than 0.001) but not from the 6th to the 12th month. With 1 alpha-(OH)D3 + 25-(OH)D3 the same phenomenon is observed at the 6th and 12th months of treatment. Before treatment, [Ca] was correlated negatively with the osteoid surfaces (OS) (r = -0.62, p = 0.01) and the number of osteoclasts per square millimeter (Ocl/mm2) (r = -0.79, p less than 0.001). At the 6th month of treatment, [Ca] was still correlated negatively with OS (r = -0.42, p = 0.05) and with Ocl/mm2 (r = -0.60, p less than 0.005). At the 12th month, the two negative correlations decreased but remained significant (r = -0.42, p = 0.05; r = -0.45, p = 0.05). These data suggest that (1) hand bone calcium analysis by neutron activation permits to follow up the peripheral bone mineral content in hemodialyzed patients and (2) the [Ca] increase only observed during the first months of treatment with vitamin D metabolites probably result from an attenuation of secondary hyperparathyroidism.

In-vivo determination of lead in the skeleton after occupational exposure to lead

ABSTRACT The concentrations of lead in the phalanges and in the blood were determined in 22 subjects who had formerly been exposed to lead in a storage battery plant, which had been closed for seven years. The bone lead concentration was measured in vivo using an ϰ-ray fluorescence technique in which two ⁵⁷Co γ-ray sources were used for generating the characteristic ϰ-rays of lead, which were measured with a Ge(Li) detector. In three subjects the variation of the lead concentration along the fore finger was measured together with the lead concentration in the tibia. The measured lead concentrations in the phalanges were between 20 μg/g (our detection limit) and 118 μg/g. The lead concentration in the phalanges was found to increase with the length of employment, but no simple relation was found between the lead concentrations in the blood and in the phalanges. The decrease in the blood lead concentration after the cessation of exposure was followed in four subjects. Seven years after exposure had ended, the blood lead concentration was found to be more dependent on the daily intake of lead than on the release of lead from the skeleton. These experimental results could be explained by a two-compartment model using exchange rates given in publications. This model has also been used to calculate the blood lead concentration that could be achieved after a sudden release of lead from the skeleton.