Does the angle between dynamic hip screw and anti-rotation screw affect the outcome of vertically oriented femoral neck fractures? A biomechanical analysis and clinical results.

OBJECTIVE: To analyze the effects of the angle between dynamic hip screw (DHS) and anti-rotation screw (AS) on vertically oriented femoral neck fractures (VOFNFs) and investigate the clinical results of them. METHODS: Eighteen synthetic femurs were simulated and divided into 3 groups. The angle between DHS and AS in anteroposterior-view was marked as α, and in lateral-view was marked as ß, thus the total angle (TA) was defined as the summation of α and ß. The groups were categorized as group A (TA ≤ 5°), B (5° < TA ≤ 10°), and C (TA > 10°), respectively. All samples were tested under incremental, cyclical loading, and loading to failure. In clinic, 80 consecutive VOFNFs in 78 patients were treated with DHS plus AS. The patients were divided into 2 groups, including 48 fractures in parallel group (TA ≤10°) and 32 in angular group (TA >10°). RESULTS: Group A and B survived during incremental and cyclical loading and endured longer than group C. Axial stiffness and failure loads were not different between group A and B, and greater than group C. Fracture gaps compressive stress was highest in group A, followed by group B and C. Forty-one fractures in parallel group and 23 in angular group healed at final follow-up. Nonunion and osteonecrosis occurred in 3 and 4 of parallel group, and 4 and 5 of angular group. CONCLUSION: The construction with TA ≤10° between DHS and AS showed superior biomechanical performance and clinical results than those with TA >10°.

Retroperitoneal bronchogenic cyst with fluid­fluid level: A case report and literature review.

Bronchogenic cyst is a benign lesion with congenital dysplasia. Although the occurrence of this type of cyst is rare in the retroperitoneum, the presence of fluid-fluid levels is an even rarer phenomenon in bronchogenic cysts. Therefore, it can be easily misdiagnosed due to the lack of a universal guideline of specific imaging manifestations. The present report describes the case of a patient with a bronchogenic cyst with fluid-fluid levels whilst also performing a brief literature review to summarize the findings of previous reports on this condition. A 48-year-old male individual presented with severe lower back pain without any obvious causes. A CT scan revealed a low-density cystic mass of ~3x4x6 cm in the left front of the T12-L2 area, which originated from the left crus of the diaphragm. MRI revealed a fluid-fluid level in the cyst. Anterior thoracolumbar surgery was performed to completely resect the mass. During the surgery, it was confirmed that the cyst originated from the left crus of the diaphragm and the lesion was diagnosed to be a bronchogenic cyst by pathological analysis. The patient's symptoms improved after the surgery and no recurrence of the cyst was observed during the 3-year follow-up period. The presence of a fluid-fluid level in a retroperitoneal bronchogenic cyst is rare, particularly in the abdominal aorta and paravertebral regions, rendering it easily misdiagnosed. It may be associated with protein, hemorrhage and calcium-containing mucus deposition in the cysts. In the present study, a rare case of fluid-fluid level in bronchogenic cyst was reported and a literature review was provided.

Erratum: Rapamycin-induced autophagy activity promotes bone fracture healing in rats.

[This corrects the article DOI: 10.3892/etm.2015.2660.].

Frog leg lateral view is a reliable predictor of the prognosis in osteonecrosis of the femoral head.

The location and size of necrotic lesions are primary factors that predict the prognosis in osteonecrosis of the femoral head (ONFH). The Japanese Investigation Committee (JIC) classification system, based on the location of the necrotic lesion, has been widely accepted and applied around the world. However, there is no report about whether the location of the necrotic area in lateral view may affect the prognosis predicted initially by the JIC classification. The purpose of this study was to investigate whether the location of the necrotic area in the frog leg lateral (FL) view would affect the prediction of prognosis for patients with ONFH. We retrospectively studied 90 hips in 76 patients with ONFH (Ficat stage I to II) after a mean follow-up of 35.3 months. All patients received standard radiographs including an anteroposterior (AP) and a FL view of the affected hip. The percentage of the necrotic area (necrotic area/whole femoral head area) was measured and compared between AP and FL view. Hips with ONFH were categorized using the JIC classification and the FL view type system, and inter- and intraobserver reliability was compared between them. All patients underwent personalized hip physiotherapy, and the cumulative survival rate with subsequent collapse and/or requirement for further hip surgery as the endpoints was evaluated for the two classification systems. The percentage of the necrotic area was found to be significantly greater in the FL views (47.0 ± 1.5%) than that in the AP views (37.7 ± 1.7%, P < .01). Intraobserver reliability in the JIC classification (mean: 0.91, range: 0.85-0.98) was higher than that in the FL view type (mean: 0.77, range: 0.63-0.89; P < .01), as well as the interobserver reliability in the JIC classification (mean: 0.74, range: 0.38-0.87) was higher than that in the FL view type (mean: 0.58, range: 0.31-0.76; P < .01). Comparisons of survival curves showed that type III in FL view type had the worst prognosis than other two divisions, following the type II. The type I was likely to gain optimal outcomes. These findings provide evidence that the location to which necrosis extended in the FL view is a reliable indicator in predicting the prognosis of ONFH.

MnTBAP inhibits bone loss in ovariectomized rats by reducing mitochondrial oxidative stress in osteoblasts.

The development of postmenopausal osteoporosis is thought to be closely related to oxidative stress. Mn(III)tetrakis (4-benzoic acid) porphyrin (MnTBAP), a novel superoxide dismutase (SOD) mimetic, could protect osteoblasts from cytotoxicity and dysfunction caused by oxidative stress. However, it is still unclear whether MnTBAP has effect on the development of postmenopausal osteoporosis. Here, we demonstrated that MnTBAP can inhibit bone mass loss and bone microarchitecture alteration, and increase the number of osteoblasts while reducing osteoclasts number, as well as improve the BMP-2 expression level in ovariectomized rat model. Additionally, MnTBAP can also prevent oxidative stress status up-regulation induced by ovariotomy and hydrogen peroxide (H2O2). Furthermore, MnTBAP reduced the effect of oxidative stress on osteoblasts differentiation and increased BMP-2 expression levels with a dose-dependent manner, via reducing the levels of mitochondrial oxidative stress in osteoblasts. Taken together, our findings provide new insights that MnTBAP inhibits bone loss in ovariectomized rats by reducing mitochondrial oxidative stress in osteoblasts, and maybe a potential drug in postmenopausal osteoporosis therapy.

Platelet-Rich Plasma-Incorporated Autologous Granular Bone Grafts Improve Outcomes of Post-Traumatic Osteonecrosis of the Femoral Head.

BACKGROUND: To investigate the effects of platelet-rich plasma (PRP)-incorporated autologous granular bone grafts for treatment in the precollapse stages (Association of Research Circulation Osseous stage II-III) of posttraumatic osteonecrosis of the femoral head. METHODS: A total of 46 patients were eligible and enrolled in the study. Twenty-four patients were treated with core decompression and PRP-incorporated autologous granular bone grafting (treatment group), and 22 patients were treated with core decompression and autologous granular bone grafting (control group). During a minimum follow-up duration of 36 months, X-ray and computed tomography were used to evaluate the radiological results, and the Harris hip score (HHS) and visual analog scale were chosen to assess the clinical results. RESULTS: Both the treatment and control groups had a significantly improved HHS (P < .001). The minimum clinically important difference for the HHS was reached in 91.7% of the treatment group and 68.2% of the control group (P < .05). The HHS and visual analog scale in the treatment group were significantly improved than that in the control group at the last follow-up (P < .05). Successful clinical and radiological results were achieved 87.5% and 79.2% in the treatment group compared with 59.1% and 50.0% in the control group (P < .05), respectively. The survival rates based on the requirement for further hip surgery as an endpoint were higher in the treatment group in comparison to those in the control group (P < .05). CONCLUSION: PRP-incorporated autologous granular bone grafting is a safe and effective procedure for treatment in the precollapse stages (Association of Research Circulation Osseous stage II-III) of posttraumatic osteonecrosis of the femoral head.

Results of combining intramedullary nailing and plate fixation for treating segmental femoral fractures.

BACKGROUND: Intramedullary nailing (IMN) is generally accepted as the standard treatment for femoral shaft fractures. However, segmental femoral fractures are considered to be a special injury type associated with high complication rates. Combined IMN and plate is proved to be a reliable method for treating complex tibia fractures with less operation time and high union rates. Therefore, the purpose of our study is to evaluate the outcome of following combined IMN and plate fixation for segmental femoral fractures. METHODS: Between February 2013 and January 2016, 18 consecutive patients with femoral shaft fracture with AO/OTA type 32-C2 were treated via combined IMN and plate. Surgical details, operative and postoperative complications, the rate of union and time to union were evaluated. RESULTS: There were 14 men and four women with a mean age of 37.8 years (range 27-52 years). All patients were followed up for a minimum of 12 months. Of the patients, 13 were closed fractures, three were Gustilo type I open fractures and two were Gustilo type II open fractures. All patients achieved union within 18.9 weeks (range 12-28 weeks) and none of them had malunion. There were no deep infections, and two patients with superficial wound infections were successfully treated with antibiotics. CONCLUSION: Combining IMN and plate fixation appears to be a reliable method for the treatment of segmental femoral shaft fractures with less operation time, high union rates and ability to maintain alignment, therefore it provides another choice for treating segmental femoral fractures.

Treatment of diaphyseal pathological fractures in children with monostotic fibrous dysplasia using cortical strut allografts and internal plating: A retrospective clinical study.

Children with fibrous dysplasia (FD) chronically suffer from pain, pathological fractures, and limb deformities. The most effective methods for managing the associated pathological fractures remain controversial. The purpose of this study was to evaluate the clinical results of the treatment of diaphyseal pathological fractures in children with monostotic fibrous dysplasia (MFD) using cortical strut allografts and internal plating.We retrospectively analyzed outcomes in nine children (5 boys, 4 girls) with diaphyseal pathological fractures due to MFD, who were treated with cortical strut allografts and internal plating (6 femoral fractures and 3 humeral fractures) between July 2007 and November 2012. The median age of patients in our study was 10 years (range 6-14 years). The fracture healing time, pain, extremity function, refracture, graft resorption, and complications were recorded to evaluate treatment effects.The median time of follow-up was 69 months (range 60-75 months). All patients had good postoperative fracture healing with a median healing time of 14 weeks (range 12-16 weeks). None experienced refracture, graft resorption, nerve injury, or limitation of extremity function or other complications. The fixation remained stable in all patients, with no evidence of loosening screws after surgery.In pediatric patients, the described surgical approach is an effective and reliable treatment method for diaphyseal pathological fractures caused by MFD. Cortical strut allografts, which act as biological bone plates, can provide good mechanical support while increasing the rate of fracture union.

Clinicopathological and prognostic value of hypoxia-inducible factor-1α in patients with bone tumor: a systematic review and meta-analysis.

BACKGROUND: Recently, many studies have shown the role of hypoxia-inducible factor-1α (HIF-1α) expression in the outcome of bone tumor. However, the results remain inconclusive. It is necessary to carry out a meta-analysis of all the current available data to clarify the relationship between HIF-1α and survival or clinicopathological features of bone tumor. METHODS: PubMed, Cochrane Library, Web of Science, China National Knowledge Internet, and Wanfang databases were used to search the relationship between HIF-1α and bone tumor. Articles investigating clinicopathological and prognostic value of HIF-1α in bone tumor patients were enrolled in this meta-analysis. Overlapping articles, duplicate data, reviews, case reports, and letters without original data were excluded. The pooled risk ratios (RRs) and hazard ratios (HRs) were used to evaluate the clinicopathological and prognostic value of HIF-1α on bone tumor patients, respectively. RESULTS: A total of 28 studies including 1443 patients were included in this meta-analysis, which were involved in three different types of bone tumor including 3 chondrosarcomas, 2 giant cell tumors of bone, and 23 osteosarcomas. Our results showed that high expression levels of HIF-1α were associated with poorer OS (overall survival) (HR = 2.61, 95% CI 2.11-3.23, P <  0.001) and shorter DFS (disease-free survival) (HR = 2.02, 95% CI 1.41-2.89, P <  0.001) in bone tumor. In addition, this study also analyzed the role of HIF-1α expression in clinicopathological features, which were closely related with the severity of bone tumor, including differentiation, clinical stage, metastasis, and microvessel density. Our results indicated that HIF-1α overexpression was significantly associated with differentiation (RR = 1.56, 95% CI 1.00-2.43, P = 0.049), clinical stage (RR = 1.75, 95% CI 1.25-2.45, P = 0.001), metastasis (RR = 1.78, 95% CI 1.58-2.00, P <  0.001), and microvessel density (SMD = 2.34, 95% CI 1.35-3.34, P <  0.001) of bone tumor. CONCLUSIONS: HIF-1α overexpression indicated an unfavorable factor for OS and DFS in bone tumor, suggesting that HIF-1α may serve as a potential prognostic marker for bone tumor.

The Clinicopathologic and Prognostic Value of Hypoxia-Inducible Factor-2α in Cancer Patients: A Systematic Review and Meta-Analysis.

Hypoxia-inducible factor-2α (HIF2α) plays an important role in the development of tumors. However, the clinicopathologic and prognostic significance of HIF2α in cancer patients remains controversial. Therefore, we performed a meta-analysis to investigate the relationship between the HIF2α status and clinical outcome in human cancer. Studies were screened online using electronic databases. The pooled risk ratios or hazard ratios (HR) with their 95% confidence intervals (CI) were calculated from available publications. Subgroup analysis, sensitivity analysis, heterogeneity, and publication bias were also conducted. A total of 854 studies with 4,345 patients were obtained in this meta-analysis. The results indicated that the increased expression of HIF2α could predict unfavorable overall survival of cancer patients on both univariate analysis (HR, 1.64; 95% CI, 1.41-1.92, P < 0.001) and multivariate analysis (HR, 2.21; 95% CI, 1.70-2.87, P < 0.001). Moreover, HIF2α overexpression was associated closely with tumor differentiation, tumor-node-metastasis stage, and lymph metastasis. In addition, there was no obvious evidence for significant publication bias in this meta-analysis. Our study indicated that HIF2α might be an indicator of poor prognosis and clinicopathologic features of tumors and could serve as a novel biomarker in human cancer.

A special superior cortex compressive fracture of femoral neck: Two case reports.

RATIONALE: Garden type I femoral neck fractures are incomplete stable fractures with impaction in valgus fractures that the question of whether there exists Garden type I femoral neck fracture is currently uncertain. There is still disagreement on the existence of the Garden type I fractures. PATIENT CONCERNS: Herein we report 2 cases with the Garden type I femoral neck fractures. Both of them had a history of simple fall. DIAGNOSES: The X-ray showed incomplete fractures of the femoral neck and the Garden classification is type I. Further computed tomography and magnetic resonance imaging were used to confirm the diagnosis of this type fracture, which showed that the superior cortex of femoral neck was discontinuous and the inferior cortex remains intact. INTERVENTIONS: The conservative treatment schedule including immobilization of the affected lower limb, strict bed rest, bed-to-wheelchair transfer training, and half-to-full weight bearing mobilization were chosen to treat the patients. OUTCOMES: Both of them achieved fracture union with conservative treatment at 3-month follow-up. No secondary displacement, signal of osteonecrosis of the femoral head or other complications occurred during 24-month follow-up in 2 cases. LESSONS: Although the Garden type I femoral neck fractures are rare, our report is in line with the real existence of it.

Lantern-shaped screw loaded with autologous bone for treating osteonecrosis of the femoral head.

BACKGROUND: Treatment for osteonecrosis of the femoral head (ONFH) in young individuals remains controversial. We developed a lantern-shaped screw, which was designed to provide mechanical support for the femoral head to prevent its collapse, for the treatment of ONFH. The purpose of this study was to investigate the efficacy and safety of the lantern-shaped screw loaded with autologous bone for the treatment of pre-collapse stages of ONFH. METHODS: Thirty-two patients were randomly divided into two groups: the lantern-shaped screw group (core decompression and lantern-shaped screw loaded with autogenous bone) and the control group (core decompression and autogenous bone graft). During 36 months follow-up after surgery, treatment results in patients were assessed by X-ray and computed tomography (CT) scanning as well as functional recovery Harris hip score (HHS). RESULTS: Successful clinical results were achieved in 15 of 16 hips (94%) in the lantern-shaped screw group compared with 10 of 16 hips (63%) in the control group (p = 0.0325). Successful radiological results were achieved in 14 of 16 hips (88%) in the lantern-shaped screw group compared with 8 of 16 hips (50%) in the control group (P = 0.0221). CONCLUSION: The lantern-shaped screw loaded with autologous bone for the treatment of pre-collapse stages of ONFH is effective and results in preventing progression of ONFH and reducing the risk of femoral head collapse. TRIAL REGISTRATION: The trial registration number: ChiCTR-TRC-13004078 (retrospectively registered at 2013-11-28).

Salmonella potsdam causing lumbar vertebral osteomyelitis: A case report.

RATIONALE: Salmonella osteomyelitis is an uncommon complication of salmonella infection, especially the salmonella vertebral osteomyelitis (SVO). PATIENT CONCERNS: We reported a case of a 29-year-old female who presented with serious lower back pain and severe limitation of motion for 50 days with no obvious inducements. She once had a fever up to 39.5°C. Physical examination only revealed limited motion of lower back without neurological complications. The laboratory results revealed no specificity. MRI of the lumbar spine revealed a spondylodiscitis at L4-L5. She underwent anterior lateral approach debridement and percutaneous posterior instrumentation. DIAGNOSES: Tissue and abscess culture grew showed Salmonella Potsdam infection. INTERVENTIONS: With susceptibility testing guidance, the patient was treated with intravenous levofloxacin and ceftazidime for a period of 3 weeks and another 3-week oral antibiotics therapy. OUTCOMES: The patient recovered well with no neurological deficits during the follow-up time. LESSONS: SVO is really rare and it alerts us the importance to consider uncommon pathogens in the differential diagnosis in which the etiological evidences are crucial of healthy individuals.

Novel Elastic Syndesmosis Hook Plate Fixation Versus Routine Screw Fixation for Syndesmosis Injury.

Unstable external-rotation type ankle fractures with concomitant syndesmosis injury commonly occur. Syndesmosis screw fixation has long been regarded as a reference standard treatment for syndesmosis injury. However, its complications and biomechanical disadvantages have become controversial; thus, we designed a novel elastic syndesmosis hook plate (ESHP) that combines the features of both rigidity and flexibility. The purpose of the present study was to introduce this new method and compare its clinical outcomes with those of routine screw fixation. We randomized 25 patients to the screw fixation group and ESHP group. The average follow-up period was 12 months. The clinical outcomes included malreduction or loss of reduction, overall complications, and function. During the follow-up period, 3 cases (25%) of malreduction were found in screw fixation group on postoperative computed tomography. In the ESHP group, only 1 patient (7.69%) had a narrowed anterior gap between the distal tibia and fibula. However, the difference in the malreduction rate between the 2 groups was not significant statistically (p = .32). The overall complication rate in the ESHP group was lower than that in the screw group, although no significant differences were found between the 2 groups. The mean visual analog scale scores in the ESHP and screw groups were 1.46 ± 1.33 and 2.42 ± 2.07, respectively. The average dorsiflexion range of motion in both groups was satisfactory (14.77° versus 12.83°; p = .16). However, a statistically significant difference was found in the plantarflexion range of motion between the 2 groups (p < .05). In addition, the ESHP group had an earlier time to return to work (p < .05). The ESHP fixation construct can stably fix syndesmosis, retain the physiologic micromotion function of the syndesmosis, and results in fewer complications compared with routine syndesmosis screw fixation for syndesmotic instability. In conclusion, our results have shown ESHP to be a viable method for treatment of syndesmosis instability.

The protective effects of triptolide on age-related bone loss in old male rats.

BACKGROUND: Previous studies have showed that triptolide have a critical role in inhibiting osteoclast formation, bone resorption and attenuating regional osteoporosis. However, the protective role of triptolide on age-related bone loss has not been investigated. In the study, we assessed the effect of triptolide supplementation on bone microstructure and bone remolding in old male rat lumbars. METHODS: Fifty-two 22-month-old male Sprague-Dawley rats were randomly assigned to either triptolide treatment group or control group. Triptolide (15 µg/kg/d) or normal saline was administered to the rats of assigned group for 8 weeks. Lumbar bone mineral density (BMD) and bone microstructure were analyzed by micro-CT. Fluorochrome labeling of the bones was performed to measure the mineral apposition rate (MAR) and bone formation rate (BFR). Osteoclast number was also measured by TRAP staining. Plasma level of osteocalcin and tartrate-resistant acid phosphatase 5b (Tracp 5b) was also analyzed. RESULTS: Micro-CT results revealed that triptolide-treated rats had significant higher BMD, bone volume over total volume (BV/TV), trabecular thickness (Tb.Th), bone trabecular number (Tb.N), and lower trabecular separation (Tb.Sp) compared to the control group. Although fluorochrome labeling result showed no significant difference in MAR and BFR between the groups, triptolide decreased osteoclast number in vivo. In addition, a significant higher level of plasma Tracp 5b was observed in the triptolide-treated rats. Furthermore, triptolide also reduced the expression of receptor for activation of NF-κB ligand (RANKL) and increased osteoprotegerin (OPG) expression in the lumbars. CONCLUSION: These results suggested that triptolide had a protective effect on age-related bone loss at least in part by reducing osteoclast number in elder rats. Therefore, triptolide might be a feasible therapeutic approach for senile osteoporosis.

Spontaneous spinal epidural hematomas: One case report and rehabilitation outcome.

RATIONALE: Spontaneous spinal epidural hematoma (SSEH) is a relatively rare but potentially disabling disease, and the classical presentation of it includes an acute onset of severe, sometimes radiating back or neck pain, followed by signs and symptoms of rapidly evolving nerve root or spinal cord compression. PATIENT CONCERNS: Here, we report a 26-year-old female patient presented with weakness in bilateral lower extremities, progressing to intense paraplegia and anesthesia without recent medical history of trauma, infection, surgery, or drug use. DIAGNOSIS: A magnetic resonance imaging (MRI) scan of spinal cord was planned and a posterior epidural hematoma of the thoracic spine was observed. INTERVENTIONS: A posterior decompression and hematoma evacuation was performed after diagnosis immediately. Early rehabilitation program of the specific kind spinal cord injury was formulated and implemented. OUTCOMES: The patient finally can handle basic living activities, such as completing wheelchair locomotion, transferring from bed to wheelchair independently after 3 months of rehabilitation. LESSONS: SSEH is a rarely occurring case in emergency. Acute chest pain and paraplegia could be the initial presentation of acute spinal epidural hemorrhage, but the diagnosis of patient without classical manifestations is still a challenge for doctors. Early diagnosis, prompt decompression, and individualized rehabilitation program can improve the prognosis and outcome.

Shapes of distal tibiofibular syndesmosis are associated with risk of recurrent lateral ankle sprains.

Distal tibiofibular syndesmosis (DTS) has wide anatomic variability in depth of incisura fibularis and shape of tibial tubercles. We designed a 3-year prospective cohort study of 300 young physical training soldiers in an Army Physical Fitness School. Ankle computed tomography (CT) scans showed that 56% of the incisura fibularis were a "C" shape, 25% were a "1" shape, and 19% were a "Г" shape. Furthermore, we invited a randomly selected subcohort of 6 participants in each shape of DTS to undergo a three-dimensional (3D) laser scanning. The "1" shape group showed widest displacement range of the DTS in the y-axis, along with the range of motion (ROM) on the position more than 20° of the ankle dorsiflexion, inversion and eversion. During the 3-year study period, 23 participants experienced recurrent lateral ankle sprains. 7 cases of the incisura fibularis were "C" shape, 13 cases were "1" shape, and 3 cases were "Г" shape. The "1" shape showed highest risk among the three shapes in incident recurrent lateral ankle sprains. We propose that it is possible to classify shapes of DTS according to the shapes of incisura fibularis, and people with "1" shape may have more risk of recurrent lateral ankle sprains.

Modified dynamic hip screw loaded with autologous bone graft for treating Pauwels type-3 vertical femoral neck fractures.

INTRODUCTION: Management of Pauwels type-3 vertical femoral neck fractures has been a challenging clinical problem as they experience high shear forces and thus a greater risk of treatment failure. There is no apparent consensus on the optimal implant type for these injuries. We developed a modified dynamic hip screw (DHS), which was designed to a cage in the lag screw, loaded with autologous bone graft for the treatment of Pauwels type-3 vertical femoral neck fractures. METHODS: Between February 2010 and January 2012, 17 consecutive patients with Pauwels type-3 vertical femoral neck fractures were treated with the modified DHS loaded with autologous bone graft. All patients were followed up for a minimum of 24 months (range, 24-36 months). Surgical details, operative and postoperative complications, the rates of nonunion and osteonecrosis and the Harris hip score were evaluated. RESULTS: There were thirteen men and four women with a mean age of 37.2 years (range, 27-52 years). There were no intraoperative complications related to this technology. All fractures healed within 14.1 weeks (range, 12 to 20 weeks). One patient required total hip replacement because of avascular necrosis of the femoral head at 27 months after surgery. According to the Harris hip score, eleven patients (64.7%) had excellent results, four (23.5%) had good results, one (5.9%) had moderate and one (5.9%) had poor result. CONCLUSIONS: The modified DHS loaded with autologous bone graft appears to be a reliable implant for the treatment of Pauwels type-3 vertical femoral neck fractures with fewer complications.

Effect of Bone Cement Volume Fraction on Adjacent Vertebral Fractures After Unilateral Percutaneous Kyphoplasty.

STUDY DESIGN: A retrospective study. SUMMARY OF BACKGROUND DATA: Complications of the bone cement used in vertebroplasty and kyphoplasty procedures have received increasingly more attention, especially for bone cement volume. OBJECTIVE: The aim of the study was to retrospectively assess the relationship between bone cement volume fraction and adjacent vertebral fracture (AVF) after unilateral percutaneous kyphoplasty (PKP). MATERIALS AND METHODS: Between 2006 and 2011, 495 patients with single-level osteoporotic vertebral compression fracture (OVCF) were surgically treated by unilateral PKP and had completed 12-month follow-up in our hospital. According to the new OVCF, they were divided into 3 groups: AVF group, non-AVF group, and normal group (who were not new OVCF). On the basis of the value of the plain radiography, the cement volume fraction for the vertebral body was calculated, and cement leakage, bone mineral density, visual analog scale, and Cobb angle of preoperative and postoperative were analyzed. RESULTS: During the follow-up, 110 (22.2%) patients had new OVCF, and others were normal (n=385). Fifty-two cases were AVF and 58 were non-AVF. The cement volume fraction of AVF group, non-AVF group, and normal group were 32.5%±5.5%, 27.3%±1.8%, and 27.1%±2.6%, respectively. The 95% confidence interval of volume fraction were (31.0, 34.1), (26.8, 27.7), and (26.9, 28.5), respectively. The AVF group showed higher cement volume fraction in 3 groups (P<0.05), and there were no significant difference between non-AVF and normal group (P>0.05). There were 19 (36.5%) patients with cement leakage in AVF group, 12 (20.7%) in non-AVF group, and 68 (17.7%) in normal group. The AVF group showed higher cement leakage (P<0.05). Compared with AVF group and normal group, non-AVF group had lower bone mineral density in preoperation. All groups reported significantly improved visual analog scale scores and Cobb angle on the day of surgery. However, there were no significant difference between the 3 groups. CONCLUSIONS: Unilateral PKP is an effective and safe procedure for patients with OVCF. However, cement volume should be determined in terms of the vertebral body fraction to obtain a favorable outcome. The risk of AVF and cement leakage will increase obviously with the cement volume fraction increased. We recommend that a bone cement volume fraction of about one fourth is suitable for unilateral PKP.

Semirigid Waved Rod System for the Treatment of the Degenerative Lumbar Diseases.

BACKGROUND: The semirigid pedicle screw instrumentation has gained wide popularity in recent decennium in lumbar fusion surgery. However, few data were documented to compare the clinical efficacy between semirigid and traditional rigid pedicle screw systems. MATERIALS AND METHODS: A total of 96 patients with degenerative lumbar diseases were selected to perform operations between 2008 and 2013. The patients were prospectively randomized into 2 groups: 50 patients were managed by semirigid waved rod systems and 46 patients were intervened by traditional rigid straight stiff rod systems. X-rays and computed tomography were utilized to examine the interbody fusion status in the follow-up in detail. Surgical parameters such as operative time, blood loss, and total hospital stay were calculated and compared. Visual Analog Scale and Oswestry Disability Index were used to assess clinical efficacy postoperatively. RESULTS: No significant differences were found about demographic data between groups. There were no significant differences regarding the surgical parameters including operative time, blood loss, and total hospital stay. Visual Analog Scale and Oswestry Disability Index postoperatively were also similar between the 2 instrumentations (P>0.05). The fusion rate was higher in the semirigid group (45/50) than in the traditional group (34/46) (P=0.039) at the final follow-up. CONCLUSIONS: Waved rod may be better in facilitating interbody fusion compared with traditional straight rod, although waved rod and straight stiff rod can both get similar clinical efficacy. Meanwhile, waved rod is likely superior in alleviating adjacent degeneration segments.