acid-phosphatase and Fractures--Closed

Osteoporosis is characterized by poor bone quality. However, it is still controversially discussed whether osteoporosis compromises fracture healing. Herein, we studied whether the course of healing of a femur fracture is affected by osteoporosis or age.. Using the senescence-accelerated osteoporotic mouse, strain P6 (SAMP6), and a closed femur fracture model, we studied the process of fracture healing in 5- and 10-month-old animals, including biomechanical, histomorphometric, and protein biochemical analysis.. In five-month-old osteoporotic SAMP6 mice, bending stiffness, callus size, and callus tissue distribution as well as the concentrations of the bone formation marker osteocalcin and the bone resorption markers tartrate-resistant acid phosphatase form 5b (TRAP) and deoxypyridinoline (DPD) did not differ from that of non-osteoporotic, senescence-resistant, strain 1 (SAMR1) controls. In contrast, femur fractures in 10-month-old SAMP6 mice showed a significantly reduced bending stiffness and an increased callus size compared to fractures in age-matched SAMR1 controls. This indicates a delayed fracture healing in advanced age SAMP6 mice. The delay of fracture healing was associated with higher concentrations of TRAP and DPD. Significant differences in osteocalcin concentrations were not found between SAMP6 animals and SAMR1 controls.. In conclusion, the present study indicates that fracture healing in osteoporotic SAMP6 mice is not affected in five-month-old animals, but delayed in animals with an age of 10 months. This is most probably due to the increased osteoclast activity in advanced age SAMP6 animals.

Topics: Acid Phosphatase; Aging; Amino Acids; Animals; Bone Resorption; Femoral Fractures; Fracture Healing; Fractures, Closed; Isoenzymes; Mice; Mice, Mutant Strains; Osteocalcin; Osteoclasts; Osteoporosis; Tartrate-Resistant Acid Phosphatase; Weight-Bearing

1) Variations in the serum concentrations of total proteins and the electrophoretic fractions, glycoprotein, mucoprotein, fibrinogen, erythrocyte sedimentation rate, calcium, phosphorus, alkaline, and acid phosphatases were analyzed until the 30th day following uncomplicated fracture of shafts of long bones of the limbs in 25 cases. 2) A significant fall of albumin with concomitant rise of alpha 1, alpha 2, and beta globulins were noted until 30th day. 3) Mucoprotein, glycoprotein, and fibrinogen showed parallel elevations with that of alpha and beta globulins. 4) The peak values of alpha 1 and alpha 2 globulins, mucoprotein, and fibrinogen were registered on the 10th day after trauma. Albumin showed maximum fall on the 10th day in all these cases. 5) Glycoprotein showed a peak value on the 5th day. 6) Total protein and gamma globulin remained almost unchanged throughout the studies. 7) Beta globulin showed higher values and paralleled more closely the fibrinogen and erythrocyte sedementation rates. 8) The elevations of beta globulin, fibrinogen, and erythrocyte sedimentation rate were higher, and persisted beyond 30 days in lower-limb fractures as compared to upper-limb fractures. 9) Serum calcium, phosphorus, alkaline phosphatase, and acid phosphatase were not significantly different following fractures and therefore did not reflect much physiologic variation. 10) The most significant changes in the levels of plasma fractions studied were conspicuous on the 10th day and lasted for about 1 month.

Topics: Acid Phosphatase; Adult; Alkaline Phosphatase; Beta-Globulins; Blood Proteins; Blood Sedimentation; Calcium; Fibrinogen; Fractures, Bone; Fractures, Closed; Glycoproteins; Humans; Middle Aged; Mucoproteins; Phosphorus