BACKGROUND: Proximal femur simple bone cysts (SBCs) are rare in children, but with a risk of pathological fractures and the associated poor outcomes. This study aimed to evaluate the functional and radiographic outcomes of children with proximal femur SBCs.
METHODS: 38 children with proximal femur SBCs treated surgically at our department, West China hospital, were enrolled in the study. Patients were divided into two groups according to whether pathological fractures presented before treatment. The non-fracture group received treatment of open curettage, cavity electrocauterization, bone grafting, and fixation (proximal femoral plate, intramedullary nail or Kirschner wire). The pathological fracture group received the same procedures of curettage, electrocauterization, grafting, and fixation. Autogenous iliac bone grafting was done in all cases, and the artificial bone was used as a supplementary based on the size of the cavity. Postoperatively, all patients underwent hip spica or similar orthosis immobilization for six weeks and received the same rehabilitation program after the removal of hip spica. Patients were evaluated by two independent observers, including the functional results based on the Ratliff\'s criteria, avascular necrosis, healing rate based on the Neer scoring system, coxa vara, and premature physeal arrest. We described the good outcome in Ratliff\'s criteria as \"Satisfactory results\", and fair and poor outcomes as \"Unsatisfactory results.\" Grade 1 and grade 2 Neer results were termed as failures in treatment, and grades 3 and 4 were considered successes and healing.
RESULTS: 38 patients with 38 hips (18 on the left side and 20 on the right side) were evaluated, including 9 females and 29 males, with a mean age of 9.0±2.6 years old (range, 5 to 14 years). There was no significant difference between these two groups in the baseline data of gender, age, side, grafting, staging, and fixation methods. The rate of unsatisfactory functional results in the pathological fractures group was 56.3% (9/16), significantly higher than that in patients without fracture (22.7%, 5/22. p= 0.047). There was also a significant difference in avascular necrosis of the femoral head between the pathological fractures group (7/16) and the group without fracture (2/22, p=0.021). Thirty cases presented with healing, including 13 in the fractures group and 17 in the non-fracture group (p=1.000), and eight cases were graded as failures (2 cases of grade 1 and 6 cases of grade 2). There were also no significant differences between these two groups in premature physeal arrest (2 in fracture group and 1 in non-fracture group, P=0.562), and Coxa vara (3 in the fracture group and 0 in non-fracture group, P=0.066).
CONCLUSIONS: Pathological fracture significantly increases the risk of unsatisfactory functional results and avascular necrosis of the femoral head in patients with femoral neck SBCs. Prophylactic treatment and fixation of SBCs in weight bearing proximal femur region is better to manage without complications than managing with pathological fractures.

暂无摘要。

UNASSIGNED: We aimed to demonstrate the methods of treatment for coxa vara with modular total hip arthroplasty (THA) and evaluate clinical and radiographic outcomes, and further survivorship at the midterm follow-up.
UNASSIGNED: We retrospectively reviewed 33 patients (42 hips) who underwent modular THA for coxa vara deformity from May 2008 to December 2019. The clinical and radiographic results, including Harris Hip Score (HHS), leg length discrepancy (LLD), greater trochanteric height, femoral offset, abductor lever arm, stem alignment and limp, and complications, were evaluated.
UNASSIGNED: The follow-up time was mean 69.9±43.7 months. Clinically, the HHS improved significantly (p<0.001) on average from 42.90±14.44 points to 89.54±4.75 points. The mean LLD decreased from 33.3±19.4 mm to 5.0±5.8 mm (p<0.001), and 27 patients (82%) thought that total equality of the lower limbs was obtained. Patients demonstrated diminished or no limping in 88% (29/33) of hips and a significant improvement of biomechanics. At the final follow-up, all stems of hips were in clinical neutral alignment and the prostheses survivorship rates for all-causes revisions was 97.6%.
UNASSIGNED: Modular THA is a valuable alternative to render favorable outcomes for treatment of osteoarthritis secondary to severe coxa vara.

UNASSIGNED: To investigate the clinical effects of a new intertrochanteric valgus osteotomy technique designed by the authors for treatment of post-traumatic coxa varus after proximal femur fractures. Retrospectively analyzed 11 patients who developed coxa vara after sustaining proximal femoral fractures were treated with intertrochanteric valgus osteotomy from December 2005 to December 2018 in our hospital. This study included 6 cases of intertrochanteric fracture deformity union, 3 cases of subtrochanteric fracture nonunion and 2 cases of femoral neck fracture nonunion. Measured the degree of coxa varus, the differences in the lower limb length and force line in all patients. Evaluated hip function with the Harris hip score. All injuries were treated with the authors\' intertrochanteric valgus osteotomy technique. The average follow-up period was 3 years and evaluated the clinical effects by radiological examination and the Harris hip score. The average neck-shaft angle increased 35.0° (99.1°-134.1°) and the average limb shortening lengthened 1.9 cm (2.9-1.0 cm) after surgery. The average operating time was 67.2 minutes and blood loss was 237.7 ml. The osteotomy position healed in all patients 3 months later. Union of the 2 old femoral neck fractures was achieved 4 and 6 months after surgery, respectively, and no femoral head necrosis occurred during follow-up. The Harris hip score increased an average of 49 points (44.1-93.1 points) at 1 year postoperatively. Our self-designed intertrochanteric valgus osteotomy technique showed a favorable clinical effect to treatment coxa vara and can be used in the clinical setting.

UNASSIGNED: To investigate the influencing factors of fracture nonunion after intramedullary nailing for subtrochanteric fractures and to construct a risk assessment model.Based on the multicenter retrospective analysis of 251 patients, all patients were divided into modeling group and verification group. In the modeling group, postoperative fracture nonunion rate, general data, fracture-related factors, surgical reduction-related factors, mechanical and biological factors were calculated, and the influencing factors of fracture nonunion were screened by univariate analysis. Logistic regression model was used for multifactor analysis to construct the risk assessment model. Based on the logistic regression model, the risk prediction model was constructed by drawing the Nomogram diagram. Through the verification group, the influencing factors were evaluated again, and the differentiation and calibration of the model were evaluated. The calibration degree was evaluated by Hosmer-Lemeshow test, goodness of fit test, and calibration curve. The discriminant degree was evaluated by the receiver operating characteristic curve.Fracture nonunion occurred in 34 of 149 patients in the modeling group. Among the 14 potential influencing factors, univariate analysis and logistic regression analysis showed that postoperative hip varus, intramedullary nail fixation failure, and reduction of fracture with large incision were the risk factors of fracture nonunion. The medial cortex fracture was seen reduced on X-Ray was a protective factor for fracture nonunion, and a regression equation was established. Based on the logistic regression model, the Nomogram diagram is drawn. Twenty-four cases of fracture nonunion occurred in the verification group. The area under the receiver operating characteristic curve was area under curve =0.883 > 0.7, indicating that there was a moderate differentiation to evaluate the occurrence of fracture nonunion after operation. The goodness of fit test: the Hosmers-Lemeshow test (X2 = 2.921, P = .712 > .05) showed that the model had a good calibration.After intramedullary nailing of subtrochanteric fracture, hip varus, failure of intramedullary nail fixation and wide surgical dissection are the risk factors of fracture nonunion, and the postoperative reduction of medial cortex fracture is protective factor.National key research and development projects: 2016YFC0105806.

UNASSIGNED: To evaluate the risk factors for developmental coxa vara (DCV) recurrence following valgus osteotomy of the proximal femur.
UNASSIGNED: We retrospectively reviewed records of 32 DCV patients (46 hips) treated surgically (2005 to 2012). Recurrence-related factors, including age at initial surgery, side, sex, fixation methods, diagnosis of coxa vara, premature capital femoral physeal closure and postoperative Hilgenreiner epiphyseal (HE) angle, head-shaft (HS) angle, medial femoral offset and posterior slope angle (PSA) were analyzed.
UNASSIGNED: At 4.7-year mean follow-up, 12 hip deformities recurred (26%). Postoperative HE angle > 41° and negative offset were statistically significant univariate and multivariate risk factors for the deformity recurrence. Increased PSA was common preoperatively, which accounted for 59% of hips. Postoperative PSA > 20° was associated with a high recurrence rate in the univariate analysis. Age was another univariate risk factor for the recurrence. Recurrence rate was 52% in the < 6.5-year age group versus 4% in the > 6.5-year age group. Other factors were not statistically significantly related to recurrence.
UNASSIGNED: DCV is a 3D deformity. To prevent recurrence, HE angle should be restored to < 41° in the coronal plane. Sagittal malalignment (abnormal PSA) should be corrected concurrently, so that, the direction of surgical correction is along the true deformity plane. During valgus osteotomy, the distal fragment should be lateralized to maintain a normal mechanical axis.
UNASSIGNED: IV.

OBJECTIVE: To investigate the orientations of the surgical epicondylar axis (SEA) of varus and non-varus knees in the coronal plane.
METHODS: One-hundred and sixty-two knees from 81 Chinese patients undergoing total knee arthroplasty (TKA) were retrospectively investigated. The angle between the medial side of the femoral mechanical axis and the SEA (MA-SEA), as well as the physiological valgus angle, was measured in the coronal plane using three-dimensional reconstruction. The joint line angle (JLA) and hip-knee-ankle angle (HKAA) were measured in long-leg weight-bearing radiographs. The mean of each parameter was compared between the varus (HKAA < 177.0°) and the non-varus knees (HKAA ≥ 177.0°) using an independent t test. Linear regression was used to assess the correlation between MA-SEA with JLA and HKAA.
RESULTS: A total of 42 non-varus knees (6 valgus and 36 neutral knees) and 98 varus knees were measured, as 22 knees were abandoned due to unrecognizable bony landmarks. The mean MA-SEA and JLA were significantly larger in non-varus knees (both, p < 0.01). The mean physiological valgus angle was 5.9 ± 1.0° for Chinese TKA patients and was significantly larger in varus knees (p < 0.01). There was a strong positive correlation between the MA-SEA and JLA (R 2 = 0.35, p < 0.05).
CONCLUSIONS: There were significant differences in the orientation of the SEA between varus and non-varus knees, which was strongly correlated with the orientation of the femoral joint line. These findings will enhance the current knowledge of knee anatomy and should prove useful for coronal alignment in TKA.
METHODS: III.

Neglected femoral neck fractures in young adults pose a great challenge to orthopedic surgeons because of the high risks of nonunion and osteonecrosis. We attempted to determine whether free vascularised fibular grafting through an anterior approach could enhance bone union, improve hip function and reduce complications in the treatment of such fractures. Thirteen patients with neglected femoral neck fractures were treated with a free vascularised fibular graft through an anterior approach between 2004 and 2008. The mean age was 30.9 years (range, 17-47 years). The average delay between injury and operation was 6.7 months (range, 1.5-22 months). All 13 cases had ununited fractures but without osteonecrosis of the femoral head on plain radiographs before coming under our care. The average follow-up was 51.2 months (range, 36-75 months). All patients had fracture union within an average of 4.8 months (range, 3-9 months). Postoperatively, 9 patients had coxa vara of 10 to 20 degrees and leg discrepancy between 0.5 to 1.5 cm. One patient had coxa vara deformity of 25 degrees and 2-cm leg discrepancy. No patients developed osteonecrosis of the femoral head or donor-site morbidity. The mean Harris hip score improved from 55.5 points preoperatively to 84.8 points postoperatively (p<0.01). This procedure may be useful and safe in the treatment of neglected femoral neck fractures in young adults, but further studies with a large number of patients are needed.