An internal locking plate to study intramembranous bone healing in a mouse femur fracture model

In most murine fracture models, the femur is stabilized by an intramedullary implant and heals predominantly through endochondral ossification. The aim of the present study was to establish a mouse model in which fractures heal intramembranously. Femur fractures of 16 SKH‐mice were stabilized by an internal locking plate. Femur fractures of another 16 animals were stabilized by an intramedullary screw. Bone repair was analyzed by radiographic, biomechanical, and histological methods. At 2 weeks, histological analysis showed a significantly smaller callus diameter and callus area after locking plate fixation. Cartilage formation within the callus could only be observed after screw fixation, but not after fracture stabilization with the locking plate. Radiological and biomechanical analysis after 2 and 5 weeks showed a significantly improved healing and a higher bending stiffness of fractures stabilized by the locking plate. Fractures stabilized by the locking plate healed exclusively by intramembranous ossification, which is most probably a result of the anatomical reduction and stable fixation. The fractures that healed by intramembranous ossification showed an increased stiffness compared to fractures that healed by endochondral ossification. This model may be used to study molecular mechanisms of intramembranous bone healing. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:397–402, 2010     

Hip fracture patients without vertebral fracture have a preferential osteopenia in the proximal femur

In 84 recent hip fracture patients, lateral spinal radiographs were examined for the presence of vertebral fracture. Sixty-three patients (75%) had the complication of vertebral fracture and 21 patients did not. Furthermore, we classified those hip fracture patients according to the presence or absence of vertebral fracture and investigated the characteristics on the extent of osteopenia in axial and peripheral bones. The bone mineral density (BMD) of the lumbar spine, proximal femur, and distal radius were lower in the hip fracture patients with vertebral fracture (HX with VX) than in the hip fracture patients without vertebral fracture (HX without VX), indicating that hip fracture patients can be further divided into subgroups. In making a comparison with age-matched controls, we found that the BMD of all examined sites in the HX with VX were significantly low. Yet, it was only in the BMD of the proximal femur that we could find a significant difference between the HX without VX and age-matched controls. We concluded that hip fracture patients without vertebral fracture have a preferential deficit bone density in the proximal femur and a similar density in the lumbar spine and distal radius when compared with normal women of their age. Received: Dec. 12, 1997 / Accepted: May 6, 1998     

Co-existing ipsilateral subcapital and subtrochanteric fracture of the proximal femur

Background  Co-existing subcapital and subtrochanteric fracture on the same side of the hip is rare. We are not aware of a similar case reported in the literature. Case study  We present a rare case of co-existing ipsilateral subcapital and subtrochanteric fracture in a 67-year-old woman. The mechanism of injury was low energy. Therapeutic implication  The outcome of internal fixation using a Proximal Femoral Nail was satisfactory. This work was carried out in the Department of Trauma and Orthopaedics, Southend University Hospital NHS Foundation Trust, Essex, UK.     

Effect of osteoporosis on bone mineral density and fracture repair in a rat femoral fracture model

Osteoporosis (OP) is one of the most prevalent bone diseases worldwide with bone fracture the major clinical consequence. The effect of OP on fracture repair is disputed and although it might be expected for fracture repair to be delayed in osteoporotic individuals, a definitive answer to this question still eludes us. The aim of this study was to clarify the effect of osteoporosis in a rodent fracture model. OP was induced in 3‐month‐old rats (n = 53) by ovariectomy (OVX) followed by an externally fixated, mid‐diaphyseal femoral osteotomy at 6 months (OVX group). A further 40 animals underwent a fracture at 6 months (control group). Animals were sacrificed at 1, 2, 4, 6, and 8 weeks postfracture with outcome measures of histology, biomechanical strength testing, pQCT, relative BMD, and motion detection. OVX animals had significantly lower BMD, slower fracture repair (histologically), reduced stiffness in the fractured femora (8 weeks) and strength in the contralateral femora (6 and 8 weeks), increased body weight, and decreased motion. This study has demonstrated that OVX is associated with decrease in BMD (particularly in trabecular bone) and a reduction in the mechanical properties of intact bone and healing fractures. The histological, biomechanical, and radiological measures of union suggest that OVX delayed fracture healing. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:384–393, 2008     

Effects of calcium supplements on fracture healing in a rat osteoporotic model

Fracture healing is a complex process, which is further complicated if the bone is osteoporotic. Calcium is one of the important minerals in bone and has been found to prevent osteoporosis but its role in fracture healing of osteoporotic bone is still unclear. We carried out a study on the effects of calcium supplementation on the late phase healing of fractured osteoporotic bone using an ovariectomized rat model. Twenty‐four female Sprague–Dawley rats were divided into three groups: sham‐operated (SO), ovariectomized‐control (OVXC), and ovariectomized + calcium supplements (Ca). The right femurs of all the rats were fractured at mid‐epiphysis and a K‐wire was inserted for internal fixation. After 2 months of treatment, the rats were sacrificed and the femora were dissected out for radiological and biomechanical assessment. As expected, osteoporosis resulted in impaired healing as shown by the poor radiological and biomechanical properties of the OVXC group. CT scans showed significantly lower callus volumes in the SO and Ca groups compared to the OVXC group. Radiological scoring of fracture healing and callus staging of the SO and Ca groups were better than the OVXC group. However, the biomechanical parameters of the Ca group were significantly lower than the SO group and similar to the OVXC group. Therefore, calcium supplements may appear to improve fracture healing of osteoporotic bone but failed to improve strength. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 28:1651–1656, 2010     

小鼠闭合性股骨骨折模型的建立与评估

[目的]建立小鼠标准闭合性股骨骨折模型。[方法]将60只C57BL/6雄性小鼠的右侧股骨髓腔插入0.45 mm直径的钢针,然后通过自行设计的骨折造模支架造成股骨中段闭合骨折。通过影像学、组织学方法观测骨折愈合进程。[结果]术后通过X线证实横型骨折55例,建模成功率为91.67%。X线、Micro-CT和组织学检查表明骨折愈合过程为典型的Ⅱ期愈合过程。[结论]通过自制骨折模型支架制作的小鼠闭合性股骨骨折模型操作简便、重复性高,其愈合为典型Ⅱ期愈合过程,可用于骨折愈合机制的研究。     

Intracapsular fracture of the proximal femur——Operative versus nonoperative management

Taken together, these reports do not provide strong evidence in favor of either internal fixation or arthroplasty over the other relative to mortality in the treatment of intraeapsular fracture of the proximal femur. However, they do suggest a higher rate of reoperations in those receiving internal fixation compared with arthroplasty. Differing patient characteristics at baseline make direct comparisons difficult.     

Fracture prevention by femoroplasty—cement augmentation of the proximal femur

The prevention of hip fractures is a desirable goal to reduce morbidity, mortality, and socio‐economic burden. We evaluated the influence on femoral strength of different clinically applicable cementing techniques as “femoroplasty.” Twenty‐eight human cadaveric femora were augmented by means of four clinically applicable percutaneous cementing techniques and then tested biomechanically against their native contralateral control to determine fracture strength in an established biomechanical model mimicking a fall on the greater trochanter. The energy applied until fracture could be significantly increased by two of the methods by 160% (53.1 Nm vs. 20.4 Nm, p < 0.001) and 164% (47.1 Nm vs. 17.8 Nm, p = 0.008), respectively. The peak load to failure was significantly increased by three of the methods by 23% (3818.3 N vs. 3095.7 N, p = 0.003), 35% (3698.4 N vs. 2737.5 N, p = 0.007), and 12% (3056.8 N vs. 2742.8 N, p = 0.005), respectively. The femora augmented with cemented double drill holes had a lower fracture strength than the single drilled ones. Experimental femoroplasty is a technically feasible procedure for the prophylactic reinforcement of the osteoporotic proximal femur and, hence, could be an auxiliary treatment option to protect the proximal femur against osteoporotic fractures. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1753–1758, 2011     

Effect of low molecular weight heparin on fracture healing in a stabilized rat femur fracture model.

The purpose of this study was to evaluate the effect of low molecular weight heparin (LMWH) on fracture healing in a standard stabilized rat femur fracture model. A closed, mid-diaphyseal transverse fracture was created in the right femur of Long-Evans rats after insertion of a 0.8-mm K-wire into the medullary canal. Animals were randomized to receive either LMWH (70 units/kg dalteparin) or an injection of normal saline daily for 2 weeks. Animals were sacrificed at 2, 3, and 6 weeks. Fracture healing was assessed by radiographs, histology, and mechanical testing. There were no significant differences between the control and LMWH groups in the percentage of animals with radiographic bridging callus at each time point. Histologic appearance of fracture healing was similar between the control and LMWH groups. There were no significant differences in the normalized mechanical properties of the control and LMWH groups at 2 and 3 weeks. At 6 weeks, the percent torque of the LMWH group was significantly greater than the control group ( p = 0.0072), however, there was no significant difference in the stiffness and energy absorption. Dalteparin, at the dosage used in this study, did not impair fracture healing in this standard stabilized rat femur fracture model.     

A double-plating approach to distal femur fracture: A clinical study

BackgroundLocked plating is one of the latest innovative options for treating supracondylar femur fractures with relatively low failure rates. Single lateral plating was often found to have a relative higher failure rate. No clinical studies of double-plating distal femur fixation have thus far been reported. The aim of this study is to present our clinical experience with this surgical approach.Patients and methodsThirty-two patients (26 females and 6 males, mean age 76 years, range 44–101) were included in the study. Eight of them patients had a periprosthetic stable implant fracture and two patients were treated for a nonunion.ResultsAll fractures, excluding one that needed bone grafting and one refracture, healed within 12 weeks. One patient needed bone grafting for delayed union and one patient needed fixation exchange due to femur re-fracture at the site of the most proximal screw. Two patients developed superficial wound infection and one patient required medial plate removal after union due to deep infection.ConclusionsBased on these promising results, we propose that the double-plating technique should be considered in the surgeon’s armamentarium for the treatment of supracondylar femur fractures, particularly in patients with poor bone quality, comminuted fractures and very low periprosthetic fractures.     

Ischemia leads to delayed union during fracture healing: a mouse model.

Vascular damage accompanying skeletal injury leads to an ischemic environment, and in clinical settings the extent of vascular damage is directly correlated with failure of skeletal repair. However, the exact mechanism(s) underlying ischemia-related defects in bone healing are not well understood. To better understand the mechanism and to facilitate development of novel interventions to treat ischemic fractures, a mouse model of long bone fracture healing in an ischemic environment was created. Ischemia was induced by femoral artery resection prior to tibia fracture. Fractures were left unstabilized or were stabilized with custom-designed external fixators. Animals with intact femoral vessels served as controls. Tissues from non-stabilized fractures were analyzed at various times from 3 to 28 days after injury (n = 5/time point). Femoral artery resection severely impaired blood supply to the fractured limbs, and perfusion to the fracture sites did not recover until 14 days post-injury. Ischemia significantly decreased the callus size (p < 0.05), and decreased bone (p < 0.05) and cartilage (p < 0.05) matrix production during healing of non-stabilized fracture. The decreased formation of skeletal tissues in ischemic limbs was accompanied by decreased cell proliferation and increased apoptosis at early time points, and increased fibrous and fatty tissues adjacent to the fracture site during the third and fourth week after injury. These alterations led to a delayed-union. Complete fracture healing was not achieved in the majority (day 21 = 4/5; day 28 = 5/5) of ischemic animals, while all control mice (n = 5/5) had evidence of bony bridging by day 21. The ratio of cartilage to bone was similar in ischemic and control limbs at days 7 and 10 in non-stabilized fractures. In stabilized fractures, which healed through direct bone formation in the nonischemic controls, ischemia decreased the amount of bone formation at days 10 and 14 (n = 5/time point) but did not induce cartilage formation. These data reveal that an ischemic insult in the hind limb prior to fracture leads to a delayed union or a nonunion, but does not favor formation of cartilage over bone. This model will be useful for testing novel therapeutic regimens to stimulate fracture healing.     

加长型PFNA治疗股骨转子下粉碎性骨折的临床研究

[目的]评价采用加长型股骨近端螺旋刀片抗旋髓内钉(proximal femoral nail anti-rotation,PFNA)治疗股骨转子下粉碎性骨折的临床疗效.[方法]2006年6月～2011年6月,本院采用AO/ASIF加长型PFNA治疗股骨转子下粉碎性骨折83例,男57例,女26例;年龄19 ～72岁,平均42.6岁,所有患者均为股骨单侧闭合性骨折,受伤至手术时间间隔为3～7d,平均4.1d.术后第1、2、3、6、9、12个月门诊随访,以后每年至少门诊复查1次.随访时所有患者均拍摄股骨中近段正、侧位X线片.临床疗效评价采用Harris髋关节功能评分标准.[结果]83例患者手术时间45 ～ 95 min,平均65.7 min;术中出血量50 ～150ml,平均86.4 ml,所有患者均为术后4～7d下地扶拐逐渐限量负重行走.83例患者均获得完整随访,随诊4,～36个月,平均18.3个月,所有患者术后未出现感染、下肢静脉血栓形成,未出现螺旋刀片切割股骨头及断钉现象,3例出现髋内翻短缩畸形;无骨折不愈合者,骨折愈合时间为3.3 ～5.7个月,平均3.6个月.按Harris髋功能评分标准:优56例,良24例,中3例,优良率96.39％( 80/83).[结论]加长型PFNA治疗具有微创、固定强度高、生物力学特性好等优点,在治疗股骨转子下粉碎性骨折时骨愈合率高、功能恢复快、并发症少.     

Optimization of transdisciplinary management of elderly with femur proximal extremity fracture: A patient-tailored plan from orthopaedics to rehabilitation

Fractures of femur proximal extremity(FFPE) are the most common fragility fractures requiring hospitalization, with a high risk of mortality, low independence in the activities of daily living and severe consequences on healthrelated quality of life. Timing for surgery has a key role in the management of elderly patients with FFPE as recommended by the Australian and New Zealand guidelines and the National Institute for Health and Care Excellence guidelines. Early surgery(within 48 h from hospital admission) allows significant benefits in terms of lower rates of postoperative complications and risk of death and can provide better functional outcomes. Therefore, time for surgery could be considered as a comorbidity marker. The choice between conservative or surgical approach surprisingly seems to be still not strongly supported by available literature, but it seems that both 30 d and 1 year risk of mortality is higher with the conservative treatment rather than with surgery. In light of these considerations, the optimization of FFPE management care is mandatory to improve functional outcomes and to reduce sanitary costs. Albeit it is widely accepted that transdisciplinary approach to patients suffering from FFPE is mandatory to optimize both short-term and long-term outcomes, the feasibility of a comprehensive approach in clinical practice is still a challenge. In particular, the large variability of figures involved could be considered both a resource and an additional disadvantage taking into account the difficulty to coordinate multidisciplinary approach covering care in all settings. Therefore, the aim of the present article was to summarize current evidence supporting transdisciplinary management of patients with FFPE, highlighting the benefits, feasibility and limitations of this approach.     

股骨转子下骨折髓内钉术后骨折不愈合风险评估模型

目的探讨股骨转子下骨折髓内钉术后骨折不愈合影响因素并构建风险评估模型。方法回顾性分析2006年2月至2018年1月于我院收治的251例股骨转子下骨折手术复位固定患者,根据收治时间不同,将纳入本研究的251例患者分为:①2006年2月至2014年2月纳入的为建模组,用于风险评估模型的构建;②2014年3月至2018年1月纳入的为验证组,用于风险评估模型效能的评价。建模组统计术后骨折不愈合率,患者的一般资料、骨折相关、手术复位相关、机械因素及生物学因素,采用单因素分析筛选骨折不愈合的影响因素。单因素分析存在统计学差异的指标,采用Logistics回归模型进行多因素分析,构建风险评估模型。通过验证组对影响因素再次评估,并对该模型的区分度和校准度进行评价。结果建模组149例患者中有34例发生骨折不愈合。在分析的13个潜在影响因素中通过单因素分析及logistic回归分析均显示术后髋内翻、髓内钉固定失效、完全切开复位为骨折不愈合危险因素,术后复位内侧皮质为骨折不愈合保护因素,并建立回归方程。以Logistic回归模型为基础,绘制列线图(又称诺莫,Nomogram图)。验证组102例中24例发生骨折不愈合,区分度检验:ROC曲线下面积为AUC=0.883>0.7,表明其有中等区分度评估术后骨折不愈合的发生。拟合优度检验:H-L检验(χ2=2.921,P=0.71>0.5)表明该模型具有较好的校准度。结论转子下骨折髓内钉术后髋内翻、髓内钉固定失效、完全切开复位为骨折不愈合的危险因素,术后复位内侧皮质为其保护因素。该风险评估模型有中等区分度以及较好的校准度,可为转子下骨折术后发生骨折不愈合的风险评估提供参考。     

锁定钢板治疗老年性股骨远端骨折

2005年4月～2007年10月,我科采用经皮微创内固定（MIPO）技术治疗老年性股骨远端骨质疏松性骨折患者15例,疗效满意。 1材料与方法 1．1病例资料本组15例,男7例,女8例,年龄57—82岁。15例术前均通过超声骨密度仪确诊为骨质疏松症患者,其中T值小于或等于年轻健康人群超声速度峰值的2．5个标准差。均在入院后3～12d手术。     

股骨近端髓内钉治疗股骨转子间骨折

目的探讨股骨近端髓内钉治疗股骨转子间骨折的疗效。方法回顾分析2001年2月～2004年2月应用股骨近端髓内钉治疗股骨转子间骨折30例。结果本组病人28例得到随访,随访时间平均8个月,骨折全部愈合,无髋内翻并发症。结论股骨近端髓内针具有抗旋转稳定性能好,手术操作简单,创伤小,是治疗转子间骨折较理想的一种方法。     

股骨近端锁定钢板在粉碎性股骨转子下骨折中的应用

2007年3月～2011年1月,笔者应用股骨近端锁定钢板固定治疗股骨转子下粉碎性骨折25例,临床效果满意. 1 材料与方法 1.1 病例资料 本组25例,男17例,女8例,年龄34～76岁.     

Sternal insufficiency fracture related to steroid-induced osteoporosis: A case report

Osteoporosis often results in fractures, deformity and disability. A rare but potentially challenging complication of osteoporosis is a sternal insufficiency fracture. This case report details a steroid-induced osteoporotic male who suffered a sternal insufficiency fracture after minimal trauma. Prompt diagnosis and appropriate management resulted in favourable outcome for the fracture, though a sequalae involving a myocardial infarction ensued with his osteoporosis and complex health history. The purpose of this case report is to heighten awareness around distinct characteristics of sternal fractures in osteoporotic patients. Discussion focuses on the incidence, mechanism, associated factors and diagnostic challenge of sternal insufficiency fractures. This case report highlights the role primary contact practitioners can play in recognition and management of sternal insufficiency fractures related to osteoporosis.