ABSTRACT
BACKGROUND: Core decompression for early adult ischemic necrosis of femoral head gets the identity of most scholars, but the postoperative femoral head easily experiences collapse. How to prevent collapse is still a problem to be solved currently. OBJECTIVE: To perform biomechanical analysis of femoral head ischemic necrosis by using the finite element method and to provide biomechanical basis for the treatment of early adult femoral head necrosis. METHODS: One fresh femur specimen died of accidental death in youth and young adults was obtained, and no deformity or fracture was found. X-ray confirmed that it did not have tumor or osteoporosis. Spiral CT was used to scan normal femoral head and neck, pulp core decompression of femoral head and neck, brace device placement and bone-graft of femoral head and neck for acquiring image data from the proximal to distal vertical longitudinal axis. Scanning data were input in the Mimics software. Finite element method was utilized for biomechanical analysis of femoral head and neck of three models. RESULTS AND CONCLUSION: (1) The stress dispersal and downward conduction of normal femoral head was concentrated in the shaft of the femur and the tensile stress was concentrated in the rotor socket. (2) After pulp core decompression, the stress concentration, displacement and strain increased in the weight-bearing area of femoral head. (3) The stress of the internal bracing was similar to that of normal femoral head. (4) The stress of weight bearing area of femoral head is concentrated, and the strain is increased, so that weight bearing area is easy to collapse after pulp core decompression. The more stress distribution, more bearing load and less strain of implant and bone graft model, are conformed to the normal mechanical properties of the normal femoral head and neck.
ABSTRACT
ObjectiveTo investigate the clinical value of ATP bioluminescence tumor chemosensitivity assay (ATP-TCA) for recurrent and refractory non-Hodgkin lymphoma (NHL) specimens in vitro.Methods Thirty-four freshlytaken recurrent andrefractoryNHL specimens weretestedin vitro for cancer chemosensitivity by ATP-TCA.ResultsDrug sensitivity of NHL specimens had heterogeneity.Different drugs had different tumor growth inhibition ratio in vitro.Response rate (RR) of the patients receiving chemotherapy according to in vitro assay was 82.4 ％ (28/34),complete response rate (CR) was 52.9 ％ (18/34).In DICE group RR was 60.0 ％ (18/30),CR rate was 33.3 ％ (10/30).In GDP group RR was 62.3 ％ (33/53),CR rate was 26.4 ％ (14/53).In ATP-TCA group RR was significantly higher than those in DICE and GDP groups (x2 =3.93,P =0.047; x2 =3.98,P =0.046).ConclusionThe results of ATP-TCA assay are correlated well with clinical treatment responses.The assay may be an important and useful method for individual-based chemotherapy of cancers.