ABSTRACT
BACKGROUND@#The reverse obliquity inter-trochanteric fracture is a distinct fracture pattern that is mechanically different from most inter-trochanteric fractures and the optional treatment of it is still controversial. The purpose of this study was to compare differences in the efficacy of a novel nail (medial support nail [MSN-II]) and proximal femoral nail anti-rotation (PFNA-II) in the treatment of reverse obliquity inter-trochanteric fractures (Arbeitsgemeinschaft fur Osteosynthesfrogen/Orthopedic Trauma Association [AO/OTA] 31-A3.1) using finite-element analysis.@*METHODS@#Modeling software was used to establish a three-dimensional model of MSN-II and PFNA-II and an A3.1 inter-trochanteric fracture model. Abaqus software was used to implement different force loads to compare finite-element biomechanical parameters such as the maximum stress in implant and the displacement of fracture site.@*RESULTS@#The femoral stress, implant stress and fracture site displacement of MSN-II was less than that of PFNA-II. The results indicated that the maximal femoral stress was 581 MPa for PFNA-II and 443 MPa for the MSN-II. The maximum stress values in the PFNA-II and MSN-II models were 291 and 241 MPa, respectively. The maximal displacements of the fracture site were 1.47 and 1.16 mm in the PFNA-II and MSN-II models, respectively.@*CONCLUSION@#Compared with PFNA-II for inter-trochanteric fracture (AO/OTA 31-A3.1), MSN-II which was designed with a triangular stability structure can provide better biomechanical stability. The MSN-II may be a feasible option for the treatment of reverse obliquity inter-trochanteric fracture.
Subject(s)
Humans , Bone Nails , Femur , Finite Element Analysis , Fracture Fixation, Intramedullary , Hip Fractures/surgery , Treatment OutcomeABSTRACT
OBJECTIVE@#A3 intertrochanteric fracture is an extremely unstable fracture, which is often treated with intramedullary nail, but the implant failure is common due to the posterior medial fragment cannot be reconstructed. A new medial sustainable nail (MSN-Ⅱ) which can reconstruct the femoral medial support by sustainable screw was introduced in this study. The mechanical effect was verified by biomechanical experiment.@*METHODS@#The loss medial support model of intertrochanteric fracture (A3) was made by artificial Sawbones model, fixed with MSN-Ⅱ and PFNA-Ⅱ, underwent axial loading and axial failure tests. The axial stiffness, yield load, displacement of head-neck fragment and torsional angle of fracture site of these nails were recorded and compared for biomechanical differences. The effect of early reconstruction of medial support with MSN-Ⅱ was determined.@*RESULTS@#The axial stiffness, yield load, the displacement of head and neck fragment when the axial load was 1 800 N and torsional angle of the fracture site after the axial failure test of MSN-Ⅱ were (222.76 ±62.46) N /mm, (4 241.71 ±847.42) N, (11.51 ±0.62) mm, (1.71 ±0.10)° respectively, while the PFNA -Ⅱ was (184.58±40.59) N /mm, (3 058.76±379.63) N, (16.15±1.36) mm, (2.52±0.26)°respectively. The difference between the two groups was statistically significant.@*CONCLUSION@#The axial stiffness of MSN-Ⅱ is better than that of PFNA-Ⅱ. The MSN-Ⅱ can bear more loads when fixed A3.3 intertrochanteric fracture and has greater axial and rotational stability. It is an effective means to reconstruct the medial support of A3 intertrochanteric fracture.
Subject(s)
Humans , Biomechanical Phenomena , Bone Nails , Bone Screws , Femur , Fracture Fixation, Intramedullary , Hip Fractures/surgeryABSTRACT
BACKGROUND@#Available research about the anatomic patterns of intertrochanteric fractures is lacking, and fracture mapping has not previously been performed on intertrochanteric fractures. This study aimed to determine the major trajectories of intertrochanteric fracture lines using computed tomography data from a series of surgically treated patients.@*METHODS@#In this study, 504 patients with intertrochanteric fractures were retrospectively analyzed. Fracture patterns were graded according to Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification. Fracture lines were transcribed onto proximal femoral templates and graphically superimposed to create a compilation of fracture maps that were subsequently divided into anterior, posterior, lateral, and medial fracture maps to create a three-dimensional (3D) pattern by reducing fragments in the 3D models. The fracture maps were then converted into frequency spectra. The major fracture patterns were assessed by focusing on the lateral femoral wall, lesser trochanter, intertrochanteric crest, and inner cortical buttress.@*RESULTS@#Anterior, posterior, lateral, and medial fracture maps were created. The majority of fracture lines (85.9%, 433/504) on the anterior maps were along the intertrochanteric line where the iliofemoral ligament was attached. In the medial plane, the majority of fracture lines (49.0%, 247/504) shown on the frequency spectrum included the turning point involving the third quadrant. In the posterior plane, the majority of fracture lines (52.0%, 262/504) involved the intertrochanteric crest from the greater to the lesser trochanter. In the lateral plane, the majority of fracture lines (62.7%, 316/504) involved the greater trochanter at the gluteus medius attachment.@*CONCLUSIONS@#The fracture patterns observed in the present study might be used to describe morphologic characteristics and aid with management strategies. Further classifications or modifications that incorporate the fracture patterns identified in this study may be used in future research.
ABSTRACT
Background@#Available research about the anatomic patterns of intertrochanteric fractures is lacking, and fracture mapping has not previously been performed on intertrochanteric fractures. This study aimed to determine the major trajectories of intertrochanteric fracture lines using computed tomography data from a series of surgically treated patients.@*Methods@#In this study, 504 patients with intertrochanteric fractures were retrospectively analyzed. Fracture patterns were graded according to Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification. Fracture lines were transcribed onto proximal femoral templates and graphically superimposed to create a compilation of fracture maps that were subsequently divided into anterior, posterior, lateral, and medial fracture maps to create a three-dimensional (3D) pattern by reducing fragments in the 3D models. The fracture maps were then converted into frequency spectra. The major fracture patterns were assessed by focusing on the lateral femoral wall, lesser trochanter, intertrochanteric crest, and inner cortical buttress.@*Results@#Anterior, posterior, lateral, and medial fracture maps were created. The majority of fracture lines (85.9%, 433/504) on the anterior maps were along the intertrochanteric line where the iliofemoral ligament was attached. In the medial plane, the majority of fracture lines (49.0%, 247/504) shown on the frequency spectrum included the turning point involving the third quadrant. In the posterior plane, the majority of fracture lines (52.0%, 262/504) involved the intertrochanteric crest from the greater to the lesser trochanter. In the lateral plane, the majority of fracture lines (62.7%, 316/504) involved the greater trochanter at the gluteus medius attachment.@*Conclusions@#The fracture patterns observed in the present study might be used to describe morphologic characteristics and aid with management strategies. Further classifications or modifications that incorporate the fracture patterns identified in this study may be used in future research.
ABSTRACT
Objective To explore the iodine nutrition level of people, prevalence of iodine deficiency disorders and the thyroid function of women of childbearing age in pasturing areas of Tibet. Methods Thirty families were selected respectively in pastoral Dangxiong county and agricultural Qushui county of Lhasa in 2009,drinking water and edible salt samples were collected to test iodine content; at least 50 people from each crowd of the following populations including children aged 8 - 10, women of childbearing age of 18 - 49 old and male adults aged 18 - 60 were randomly sampled and to measure their urinary iodine content and for thyroid palpation. Direct titrimetric method was used to test salt iodine(GB/T 13025.7-1999); As3+-Ce4+ oxidation reduction process to test water iodine (GB/T 5750.1-2006); As3+-Ce4+ catalytic spectrophotometry using ammonium persulfate digestion to test urine iodine(WS/T 107-2006), and goiter examination was based on Diagnostic and Classificatory Criteria of Endemic Goiter (WS 276-2007). Results The median of water iodine was 1.3 μg/L in pasturing area and 0.7 μg/L in agricultural areas, there was no statistical significant difference between them(Z =- 1.809, P ＞ 0.05).There was no iodized salt used in pastoral people, but iodized salt coverage rate was 90.0％(27/30) in agricultural residents. The median of urinary iodine among people of pasturing areas was 50.2 μg/L, lower than that of agricultural areas( 193.2 μg/L, Z =- 10.48, P ＜ 0.01 ). However, the goiter rate in pasturing area[1.0％(1/100)]was significantly lower than that of agricultural areas[18.0％(18/100) , x2 =16.8, P ＜ 0.01]. Serum level of FT4 and TT4 in pastoral population[(14.0 ± 2.0)pmol/L, (85.6 ± 17.5)nmol/L] was significantly lower than that of agricultural areas[(16.2 ± 6.3)pmol/L, (95.4 ± 21.1)nmoL/L, t =- 2.06, - 2.20, all P ＜ 0.05]. The thyroid dysfunction rate[5.9％ (2/34)]and subclinical hypothyroidism rate[2.9％ (1/34)]in pastoral population was significantly lower than that of agricultural areas[25.5％(12/47), 21.3％(10/47), x2 =5.328, 5.651, all P ＜ 0.05]. Conclusions Pastoral areas of iodine intake is significantly lower than the agricultural areas, urinary iodine levels reflect a serious iodine deficiency in pastoral people, but the blood biochemical and urinary iodine and goiter rate does not match,and shows hidden iodine hunger, which does not constitute a goiter epidemic.