Echocardiographic assessment of right ventricle adaptation to endurance training in young rowers - speckle tracking echocardiography.

The aim of this study was to determine the relationship between the degree of cardiorespiratory fitness and the function of the right ventricle (RV). 117 rowers, age 17.5±1.5 years. All subjects underwent cardiopulmonary exercise. Standard echocardiography and 2D speckle tracking echocardiography with evaluation of longitudinal strain in each segment of the RV (basal - RVLS-B; mid - RVLS-M, apical - RVLS-A) and global RV free-wall strain (RVLS-G) were performed. RVLS-B values were lower compared to the RVLS-M (-25.8±4.4 vs -29.3±3.5; p<0.001) and RVLS-A values (-25.8±4.4 vs -26.2±3.4; p=0.85). Correlations between VO2max and RVLS were observed in men: RVLS-G strain (r = 0.43; p <0.001); RVLS-B (r = 0.30; p = 0.02); RVLS-M (r = 0.38; p = 0.02). A similar relationship was not observed in the group of women. The strongest predictors corresponding to a change in global and basal strain were VO2max and training time: RVLS-G (VO2max: ß = 0.18, p = 0.003; training time: ß = -0.39; p = 0.02) and RVLS-B (VO2max: ß = 0.23; p = 0.0001 training time: ß = -1.16; p = 0.0001). The global and regional reduction of RV systolic function positively correlates with the level of fitness, and this relationship is observed already in young athletes. The character of the relationship between RV deformation parameters and the variables that determine the physical performance depend on gender. The dependencies apply to the proximal fragment of the RV inflow tract, which may be a response to the type of flow during exercise in endurance athletes.

NO ASSOCIATION BETWEEN tHbmass AND POLYMORPHISMS IN THE HBB GENE IN ENDURANCE ATHLETES.

The aim of this study was to examine the association between tHbmass and HBB gene polymorphisms in athletes of endurance disciplines. Eighty-two well-trained athletes (female n=36, male n=46), aged 19.3 ± 2.7 years, representing cross country skiing (n=37) and middle- and long-distance running (n=45), participated in the study. Genotyping for 2 polymorphisms in the HBB gene (- 551C/T and intron 2, +16 C/G) was performed using restriction fragment length polymorphism analysis. Total haemoglobin mass (tHbmass) was determined by the optimized carbon monoxide rebreathing method. Blood morphology, indices of iron status (ferritin, transferrin receptor and total iron binding capacity) and C reactive protein were also determined. No differences were found in the HBB genotype and allele frequencies between male and female athletes. Regardless of the polymorphisms, no relationships were found between HBB genotypes as well as alleles and relative values of tHbmass, expressed per body mass (g · kg(-1) BM), both in female and male athletes. Our results demonstrated that -551 C/T and intron 2, +16 C/G polymorphisms of the HBB gene have no association with total haemoglobin mass in endurance athletes. It cannot be ruled out that several polymorphisms, each with a small but significant contribution, may be responsible for the amount of haemoglobin.

Reduction and stabilization of grade IV spondylolisthesis.

Virtually any degree of spondylolisthesis can be reduced and held using variable screw placement (VSP) slotted plates and transpedicular screws. All of the soft tissue holding the displaced vertebrae must be stretched prior to pulling the vertebrae back into normal alignment. Complete control of the displaced vertebrae is gained through the transpedicular screws, and fixation is accomplished by bolting the screws to the spine plates that have been bent to achieve the proper lumbar lordosis. Ultimate stability is gained by both a bilateral lateral and interbody fusion.

Posterior lumbar interbody fusion and plates.

Posterior lumbar interbody fusion (PLIF) is accepted by many authors as the surgical treatment for herniated discs, degenerative disc conditions, and Grades I and II spondylolistheses. PLIF is now used in conjunction with newly developed segmental spine plates by using transpedicular screw fixation to enhance the osteosynthesis and success rate of interbody fusion. To date, 104 fusions have been performed in 67 patients with no dislocations of any interbody grafts and no indication of absorption, pseudoarthrosis, or infections.

Total vertebral body and pedicle arthroplasty.

Two new spinal procedures, a total vertebral body replacement using a one-stage posterior approach, and artificial pedicle replacement for extensive decompression laminectomies, are performed with the aid of a special segmental spine plating system. These spine plates, with their unique individual pedicle screw placement, create immediate and totally-rigid fixation as well as segmental control of each vertebral body. Surgeons are now free to perform laminectomies to their fullest extent without the consequence of an uncorrected, unstable back. The purpose of the procedure is to permit the patient to recover without immobilization or prolonged bed rest, and to return to normal activity and work without pain. Three cases are presented to demonstrate potential surgical indications and techniques.

Segmental spine plates with pedicle screw fixation. A new internal fixation device for disorders of the lumbar and thoracolumbar spine.

A new segmental spine plate fixation system, utilizing a posterior approach and screw fixation, has been developed for disorders of the lower thoracic or lumbar spine. The indications are significant instability and severe pain relieved by immobilization. This new system uses multiple segmental fixation points through the pedicle "force nucleus" of the vertebral body. The spine plates can be contoured for anatomic positioning, reduction, and rigid stabilization to enhance graft consolidation and fusion. The surgical fixation technique is demonstrated in five case presentations illustrating the application and versatility of the method.