Measurement Of Proximal Femoral Medullary Cavity And Clinical Application Of Tri-Lock Bone Preservation Stem

Objective:We aimed at measuring proximal femoral medullary cavity anatomical and morphological parameters using two different methods(X-ray and CT measurements); assessing morphological characteristics of marrow cavities in proximal femurs and combining with the characteristics of Tri-Lock Bone Preservation Stem(BPS) to evaluate the clinical application of Tri-Lock BPS. Methods:1.Form May 2013 to May 2015, we randomly selected 80 patients, including male and female 40 cases in each. Carry out hip joint X-ray and CT 3D scanning of femur, measured anatomic and morphological parameters of proximal femoral medullary cavity respectively, assess the morphological characteristics and discuss whether the Tri-Lock BPS and medullary cavity;2.Including 30 patients(38 hips) using Tri-Lock BPS, postoperative follow-up at regular intervals, by comparing the preoperative and postoperative Harris hip score to evaluate operative effects and discuss the matching characteristic of Tri-Lock BPS and medullary cavity. Results:1.X-ray measurements: 1) There was no significant correlation between male age and proximal femoral medullary cavity parameters, a positive relationship between female age and transverse diameter of isthmus, and a negative correlation between female age and CFI; 2) There was no significant difference between gender and CFI, there were significant differences between gender and T+20, T0, T-20, transverse diameter of isthmus, and MCFI; 3) There was no significant correlation between CFI and T-20、Body mass index, significant correlations between age, T+20, T0, T-20, transverse diameter of isthmus and MCFI.2.CT measurements: 1) Canal Torsion Angle of first part was 7.5±1.5o, Torsion Angle rate was 0.87±0.20o/mm; Canal Torsion Angle of second part was 5.5±1.1o, Torsion Angle rate was 0.19±0.09o/mm; Canal Torsion Angle of third part was 48.1±4.9o, Torsion Angle rate was 0.52±0.11o/mm, between the former two parts of the medullary cavity; 2) The average values of TCFI and TMCFI were 4.4±0.8 and 2.8±0.4 respectively; 3) Whole shape of cross section of effective cavity by the ovoid gradually tends to be round, and cross section of long axis forward gradually.3.All of the patients that using Tri-Lock BPS were required postoperative follow-up, at least 6 months, the longest was 33 months, and with the average of 19.5 months. All cases that postoperative hip joint function recovered well. Preoperative Harris score was 45.3±4.3, postoperative final score was 94.1±5.4, which compare the preoperative have improve significantly(P < 0.05) Conclusion:1.proximal femoral medullary cavity geometric torsion, the minimized torsion degree between the edge of lesser trochanter, is the best bearing parts with proximal prosthesis and femoral medullary cavity;2.the difference of trochanter angle and femoral anteversion angle, combine with the advantage of Tri-Lock BPS that proximal prosthesis rectangular(taper) design and resistance to rotation, prosthesis implantation accordance with the direction of femoral anteversion angle;3.the good matching between Tri-Lock BPS and chimney medullary cavity and normal medullary cavity, suit to the majority of patients; 4) Tri-Loc BPS obtain satisfying effect on early clinical treatment and can reserve bone mass, much more suitable for young patients.