Analysis Services

Phenotyping in Trabecular and Cortical Bone

Using the BIOQUANT OSTEO software, BIOQUANT can provide a range of data related to skeletal phenotype. BIOQUANT’s customizable data structure allows for complete customization of the analysis report. Contact us to discuss your data requirements.

Standard Bone Structure Data

  • TV (Tissue Volume) mm2
    The total area measured. Primary data are collected in μm2.

  • BV (Bone Volume) mm2
    The total area of bone, both mineralized bone and osteoid within the tissue volume. Primary data are collected in μm2.

  • BV/TV %
    Bone Volume normalized by Tissue Volume.

  • BS (Bone Surface) mm
    The total perimeter of the bone within the Tissue Volume. Does not include the surface segements where the bone crosses out of the Tissue Volume. Primary data are collected in μm.

  • BS/BV mm-1
    Bone Surface normalized by Bone Volume. A measure of the bone's availability for cellular or chemical reactions. A higher BS/BV means a more irregular shape with proportionally more surface area available for activity.

  • Tb.Dm (Trabecular Diameter) mm
    Tb.Dm = 4*(BV/BS). The estimated diameter of an individual trabeculum using the rod model. The rod model assumes trabeculae are cylindrical rods as opposed to the plate model used in humans which assumes trabeculae are flat rectangular slabs.

  • Tb.N (Trabecular Number) mm-1
    Tb.N = SQRT(4/3.141*BV/TV)*(1/Tb.Dm). Rod Model. For a certain amount of bone, the number trabeculae of diameter Tb.Dm that can be constructed per mm.

  • Tb.Sp (Trabecular Separation) mm
    Tb.Sp = (SQRT(3.141/4*TV/BV)-1)*Tb.Dm. Rod model. The mean distance between the surfaces of adjacent trabeculae within the tissue volume.

Standard Osteoblast Data

  • Ob.N/BS #/mm
    Number of Osteoblasts per unit of Bone Surface. Bone lining cells don’t count here. Ob.N data in rodents tends to be highly subjective since the distinction between active osteoblast and bone lining cells is generally based on location and morphology.

  • Ob.S/BS %
    Length of bone surface underneath osteoblasts, as a percentage of bone surface. Lining cells don’t count here either.

  • OS/BS %
    Length of osteoid surface as a percentage of bone surface. Hard to measure in many rodent models since it tends to be thin. Osteoblast Surface often used instead.

  • O.Wi μm
    The mean of all osteoid seam width measurements in the animal. Widths are measured perpendicularly at regular intervals along the surface. Hard to measure in many rodent models.

Standard Osteoclast Data

  • Oc.S (Osteoclast Surface) mm
    Length of bone surface underneath an osteoclast. Recording one measurement per osteoclast creates a shortcut to counting osteoclasts. Primary data are collected in μm.

  • Oc.N/BS (Osteoclast Number) #
    Number of osteoclasts per unit of bone surface. A shortcut for counting osteoclasts is to measure one osteoclast surface per cell then count the number of osteoclast surface measurements.

  • Oc.S/BS %
    Length of osteoclast surface as a percentage of bone surface.

Standard Adipocyte Data

  • Ad.N/TV (Adipocyte Number) mm2
    Adipocyte number per unit area of tissue volume. Also called adipocyte density. Tricky to measure because adipocytes tend to clump together and the boundaries between them are very thin. However, determining the boundaries of individual adipocytes opens up other parameters described below.

  • Ad.Position (Adipocyte Position)
    XYZ position of the centers of individual adipocytes. Used for spatial analysis of adipocyte distribution and cluster analysis.

  • Ad.Dm (Adipoctye Diameter) μm
    The minimum diameter of a single adipocyte

  • Ad.Pm (Adipocyte Perimeter) μm
    The mean perimeter of a single adiopcyte.

  • Ad.A (Adipocyte Area) μm2
    The mean cross-sectional area of a single adiopcyte.

  • ∑Ad.V/Ma.V
    Total adipocyte volume as a percentage of marrow volume. Alternatively ∑Ad.V/Hm.V, total adipocyte volume as a percentage of hematopoetic volume or ∑Ad.V/TV.

  • Ma.V/TV %
    Marrow area as a percentage of tissue volume.

  • Hm.V/TV %
    Hematopoetic area as a percentage of tissue volume.

Standard Bone Remodeling Data

  • sLS (Single Labeled Surface) mm
    Site of osteoid mineralization, indicated by a single fluorescent label.

  • dLS (Double Labeled Surface) mm
    Site of osteoid mineralization, indicated by two parallel fluorescent labels. Mineralization was occurring over the entire interlabel time.

  • MS (Mineralizing Surface) mm
    MS = sLS/2+dLS.
    The length of bone surface mineralizing for the entire labeling period. The assumption is that half of the single label was active for the first half of the labeling period and the other half of the surface was active for the last half. Hence, sLS/2 is the length of single label surface active for the entire period.

  • Ir.L.Wi (Interlabel Width) μm
    Mean of all direct measurements of the distance between double labels. Distances between labels are measured at randomized regular intervals (often every 50 microns) along the bone surface.

  • Ir.L.t (Interlabel Time) days
    The time between injections used to label the mineralizing surfaces. Younger animals have shorter intervals, like 5 days. Older animals need more time, like 7 days

  • MAR (Mineral Apposition Rate) μm/day
    MAR = Ir.L.Wi/Ir.L.t.
    The average rate at which osteoid mineralizes. A measure of average individual osteoblast activity. Does not consider the amount of bone surface where this process is actually occurring. An animal with one osteoid seam and an animal with 100 osteoid seams could have identical MAR values. Compare BFR/BS which does incorporate the amount of bone surface forming bone.

  • Aj.AR (Adjusted Apposition Rate) μm/day
    MAR*MS/OS
    The average rate at which osteoid is mineralized, scaled to the osteoid surface. It’s basically BFR/OS. In growing rodents, generally Aj.Ar = MAR.

  • BFR/BS (Bone Formation Rate, Normalized by Bone Surface) μm/day
    BFR/BS = MAR*MS/BS.
    The rate at which new bone in mineralized, scaled by the percent of bone surface actually forming new bone (MS/BS). Less than the MAR, which is unscaled. Well suited for the discussion of hormonal effects on bone remodeling since the bone surface is the site of significant osteoblast and osteoclast action.

  • BFR/BV (Bone Formation Rate, Normalized by Bone Volume) (μm/day)/mm
    BFR/BV = MAR*MS/BV.
    Also called Bone Turnover Rate, the percent of the bone volume which is replaced in a day. Often extrapolated to %/year since the number can be very small.

  • BFR/TV (Bone Formation Rate, Normalized by Tissue Volume) (μm/day)/mm
    BFR/TV = MAR*MS/TV.
    The percent of the tissue volume which is replaced daily. Well suited for the discussion of biochemical markers of bone remodeling since bio-markers tend to derive from the entire tissue. Often extrapolated to %/year since the number can be very small. Since BV is less than TV, BFR/TV will be less than BFR/BV.

  • Omt (Osteoid Maturation Time) days
    Omt = O.Wi/MAR. The mean time it takes for an osteoid seam to begin to mineralize.

  • Mlt (Mineralization Lag Time) days
    Mlt = O.Wi/Aj.Ar. The mean time between the addition of a new layer of osteoid matrix and the onset of mineralization of that same new osteoid matrix.