An experimental study on the effect of the induced avascular necrosis of the femoral head on the femoral anteversion was made in the hips of 74 three to four-week-old rabbits. The results were as follows; l. In 18 of the 74 operated rabbits, a relative increase of anteversion was observed on the operated side, as compared with the nonoperated femur, the differences ranging from 10 to 75°(average increase was 25.9°). 2. Anteversion increase was actually internal rotation of femoral shaft starting from the subtrochanteric level and progressively increasing downward with spiral fashion. 3. The cause of anteversion increase was not proved in this experiment, but anteversion increase was a result of avascular necrosis.
Femur ; Head ; Hip ; Necrosis ; Rabbits

OBJECTIVETo compare emu necrotic femoral head micro structure repaired in two different methods.

METHODSFifteen adult emus were divided into 3 groups (all n=5), and the right femoral head was selected to research. The first group was the control group; in the second group, femoral head necrosis was made by cryogen with liquid nitrogen; and in the third group, femoral head necrosis was made by local pure ethanol injection. Right femurs were taken for micro CT examination,then femoral head micro structures were compared among these three groups.

RESULTSNo infection or unexpected death was found in all groups. Compared with normal group, necrotic femoral heads in cryogen group showed that bone mineral density significantly reduced after repaire (P=0.015), trabecular space significantly reduced (P=0.001), bone volume fraction significantly enlarged (P=0.036), bone surface/volume fraction (P=0.032) and trabecular numbers (P=0.002) significantly enlarged; trabecular thickness showed no significant difference (P=0.060). Compared with control group, necrotic femoral heads in ethanol group showed that bone mineral density significantly enlarged after repaire (P=0.001), trabecular thickness (P=0.003) and bone surface/volume fraction (P=0.022) significantly enlarged, trabecular space (P=0.001) and bone volume fraction (P=0.001) significantly reduced; the trabecular numbers showed no significant difference (P=0.143). Compared with ethanol group, necrotic femoral heads in cryogen group showed significant lower bone mineral density after repair (P=0.001), significantly lower bone volume fraction (P=0.001), significantly lower trabecular thickness (P=0.001), significantly higher bone surface/volume fraction (P=0.022) and higher trabecular numbers (P=0.003); the trabecular space showed no significant difference (P=0.398).

CONCLUSIONDifferent repair methods make reconstructed femoral head weight bearing area have different bone structure and bone mineral density, along with different bone trabecular quality.

With the in-depth understanding of osteonecrosis of femoral head (ONFH), and more and more patients seeking medical treatment in the early stage of the disease, surgical treatment of femoral head necrosis alone is no longer sufficient for the current treatment of patients' demand, how to rationally and effectively apply drugs to strengthen the early prevention and treatment of femoral head necrosis and delay the progression of disease is becoming more and more important. This article combines the latest expert consensus and evidence-based medical evidence on the principles of ONFH diagnosis and treatment in Chinese and Western medicine at home and abroad, combined with domestic actual clinical application experience, and is organized by experts from Association Related to Circulation Osseous Chinese Microcirculation Society (CSM-ARCO) to write this consensus, focusing on the types of ONFH drugs, the characteristics, safety, rationality and basic principles of drug use provide reference opinions for the safe, reasonable, standardized and effective drug use of medical institutions at all levels. This consensus is only an expert guideline based on literature and clinical experience, not as a requirement for mandatory implementation, let alone as a legal basis. The clinical practice could be tailored to the actual local conditions to develop appropriate prevention and treatment measures for patients.
Humans ; Consensus ; Femur Head ; Femur Head Necrosis/prevention & control*

PURPOSE: To observe the morphological changes of the femoral head following vascular infarct produced by surgical devascularization of the capital femoral epiphysis in a mongrel puppy model. MATERIALS AND METHODS: Forty-six mongrel, weaned puppies, 7 to 9 weeks old, and between 1.5 to 2.5 kg in weight, were experimentedupon. They were divided into three groups: 12 underwent only simple capsular incision (Group A), 18 underwent ligamentum teres disruptionwith temporary subluxation of the hip joint (Group B), and 16 underwent both ligamentum teres and posterior retinacular arterydisruption (Group C). Three to five puppies in each experimental group were periodically sacrificed at 2 weeks and at 1, 2, 5 months, postoperatively. Both femurs, extracted from the sacrificed puppies, were studied by eye, radiographically and histologically. RESULTS: Puppies from the single (Group B) and double devascularization groups (Group C) showed definite findings of vascular infarct macroscopically, radiologically, and histologically. These findings were more frequent and severe in the group with the double infarct thanthe single infarct. CONCLUSION: Morphological changes similar to those seen in human Legg-Calve-Perthes' disease (LCPD) were observed in puppy specimens. This puppy model of LCPD may be useful for experimental studies.
Epiphyses ; Femur ; Head* ; Hip Joint ; Humans ; Necrosis*

PURPOSE: We investigated coagulation disorders in Korean patients of idiopathic avascular necrosis of the femoral head. MATERIALS AND METHODS: Ten laboratory parameters related with coagulation pathway were measured and analyzed in fifty-three patients with idiopathic avascular necrosis of the femoral head and compared the results with those of thirty-one healthy persons. RESULTS: Differences in the values of plasminogen activator inhibitor and D-dimer in the two groups were statistically significant (p<0.05). The number of three or four abnormal parameters in the patient group was nearly twice that of the control. Hypofibrinolytic activity, determined by increased plasminogen activator inhibitor and lipoprotein(a), were observed in eleven cases (20.8%) of the patient group. CONCLUSION: The abnormal results that were observed in the patient group may contribute to the predisposition of thrombotic venous occlusion in the head of the femur, leading to avascular necrosis of the femoral head.
Femur ; Head* ; Humans ; Lipoprotein(a) ; Necrosis* ; Plasminogen Activators

There are many methods of conservative treatment for early non-traumatic osteonecrosis of femoral head, but still lack of a mature and effective treatment. Gene therapy is a new treatment method for non-traumatic osteonecrosis of femoral head in recent years. This article showed that the non-traumatic osteonecrosis of femoral head related to progress and problems on pathogenesy, molecular biology foundation, exogenous theoretical gene,carrier selection and so on, discussed some problems and countermeasure and future applications.
Femur Head Necrosis ; therapy ; Genetic Therapy ; Humans

In spite of recent development in fixation technique we still have lots of complication including avascular necrosis of femoral head. For many years, orthopaedic surgeon have been searching for a simple, safe, accurate and reliable clinical test to asses the vascular status of the femoral head. In early detection of viability of the femoral head, nothing is more certain than bone scan at the moment. Bone scan can detect or predict the viability of the femoral head. Subramanian and McAfee introduced 99mTc-Sn-polyphosphate as a bone seeking agents. We applied serial bone scan in 19 cases of femur neck fractures from 1982 to 1985 at the department of orthopaedic surgery, National Medical Center. The results were as follows; 1. The uptake ratio of displaced and undisplaced group based on preoperative radiography was 1.ZO, 1.46, 1.52, 1.55, and 0.63, 1.23, 1.81, 1.58 in average in postoperative bone scan interval 1–2 wks, 3 months, 6 months, 12 months. The bone scan uptake ratio was lower in the former than the latter, but after 3 months, there was no remarkable difference between them. 2. At the time of 1 to 2 weeks, 3 months, 6 months and 12 months, uneventful group was 0.74, 1.27, 1.72, 1.62 and avascular necrosis group 0.13, 0.18, 0.30, 0.67 in the uptake ratio. In 2 cases of avascular necrosis, the uptake ratio was markedly decreased. 3. There was no difference between the group operated within 48 hour after injury and the group delayed later.
Equidae ; Femoral Neck Fractures ; Femur Neck ; Femur ; Head ; Necrosis ; Radiography

The presence of anterior hip dislocation along with contralateral posterior hip dislocation in the absence of other major traumas is a distinctly rare injury pattern. We report such a case, along with a review of previous cases. A 40-year-old male patient after motorcycle skidding had posterior dislocation of the left hip and anterior dislocation of the right one without other associated injuries. The patient underwent successful closed reduction of both hips. The clinical course and follow-up assessment of the patient was uneventful.
Anemia, Sickle Cell ; Femur Head ; injuries ; Femur Head Necrosis ; Femur Neck ; Fractures, Spontaneous ; Hip Dislocation ; Humans

Avascular necrosis (AVN) is a disease characterized by the temporary or permanent loss of the blood supply to the bones, resulting from many possible causes, including radiation therapy. The femoral head is known to be the most common site of AVN. The authors encountered two cases of AVN of the femoral head among 557 patients with cervical cancer treated with whole pelvic radiation therapy at the Samsung Medical Center. AVN of the femoral head was presented with a sclerotic density change in a plain roentgenography and a decreased signal intensity lesion on the T1 and T2 weighted phases of a magnetic resonance image (MRI). Although it is a very rare complication after whole pelvic radiation therapy, AVN of the femoral head should be considered when characteristic imaging findings appear on follow-up examinations.
Femur ; Femur Head ; Follow-Up Studies ; Head ; Humans ; Magnetic Resonance Spectroscopy ; Necrosis ; Uterine Cervical Neoplasms

BACKGROUNDFeatures of necrotic lesions and various interventions could affect the biomechanics of the femoral head. A three-dimensional finite-element analysis was designed to demonstrate necrotic femoral head stress changes with various sizes of necrotic lesions, and evaluate the effect of tantalum rods on preventing femoral head cracking.

METHODSFemoral computed tomography scans were used to build a normal three-dimensional finite-element femoral head model in a computer. Based on the normal model, necrotic models of different lesion diameters (15 mm, 20 mm and 30 mm) were created, as were the repaired models with tantalum rods for each diameter. After a series of meshing and force loading, the von Mises stress distributions, simulating single-legged stance, and stresses on specific points under loaded conditions were determined for each model.

RESULTSDeep exploration into the burdened area of the femoral head indicated that higher stresses to the femoral head were observed with a larger necrotic lesion; the largest stress concentration, 91.3 MPa, was found on the femoral head with a lesion diameter of 30 mm. By contrast, topical stress on the surface of the necrotic regions was lowered following implantation of a tantalum rod, and the changes in stress were significant in models with lesions of 15 mm and 30 mm in diameter, with the best biomechanical benefit from the tantalum rod found with a lesion diameter of 15 mm.

CONCLUSIONSFemoral heads with larger necrotic lesions usually have a higher stress concentration and a higher risk of collapse. Various sized lesions on the femoral head can benefit from the mechanical support offered by the implantation of a tantalum rod; however, femoral heads with smaller sized lesions may benefit more. A thorough evaluation of the lesion size should be conducted prior to the use of tantalum rod implants in the treatment of femoral head necrosis.