Biomechanical comparison of stability of tibiotalocalcaneal arthrodesis with two different intramedullary retrograde nails

BackgroundThe aim of the study was to compare the initial construct stability of two retrograde intramedullary nail systems for tibiotalocalcaneal arthrodesis (TTCF) (A3, Small Bone Innovations; HAN, Synthes) in a biomechanical cadaver study.MethodsNine pairs of human cadaver bones were instrumented with two different retrograde nail systems. One tibia from each pair was randomized to either rod. The bone mineral density was determined via tomography to ensure the characteristics in each pair of tibiae were similar. All tests were performed in load-control. Displacements and forces were acquired by the sensors of the machine at a rate of 64 Hz. Specimens were tested in a stepwise progression starting with six times ±125N with a frequency of 1 Hz for 250 cycles each step was performed (1500 cycles). The maximum load was then increased to ±250N for another 14 steps or until specimen failure occurred (up to 3500 cycles).ResultsAverage bone mineral density was 67.4 mgHA/ccm and did not differ significantly between groups (t-test, p = .28). Under cyclic loading, the range of motion (dorsiflexion/plantarflexion) at 250N was significantly lower for the HAN-group with 7.2 ± 2.3 mm compared to the A3-group with 11.8 ± 2.9 mm (t-test, p < 0.01). Failure was registered for the HAN after 4571 ± 1134 cycles and after 2344 ± 1195 cycles for the A3 (t-test, p = .031). Bone mineral density significantly correlated with the number of cycles to failure in both groups (Spearman-Rho, r > .69, p < 0.01).ConclusionsThe high specimen age and low bone density simulates an osteoporotic bone situation. The HAN with only lateral distal bend but two calcaneal locking screws showed higher stability (higher number of cycles to failure and lower motion such as dorsiflexion/plantarflexion during cyclic loading) than the A3 with additional distal dorsal bend but only one calcaneal locking screw. Both constructs showed sufficient stability compared with earlier data from a similar test model.Clinical relevanceThe data suggest that both implants allow for sufficient primary stability for TTCF in osteoporotic and consequently also in non-osteoporotic bone.Level of evidenceNot applicable, experimental basic science study.     

复位股骨大粗隆顶点骨折对PFNA治疗不稳定股骨粗隆间骨折预后的影响

目的评估应用股骨近端防旋髓内钉（PFNA）内固定治疗合并股骨大粗隆顶点局部骨折的不稳定股骨粗隆间骨折术中将股骨大粗隆顶点局部骨折复位对预后的影响。方法合并股骨大粗隆顶点局部骨折的不稳定股骨粗隆间骨折46例,股骨大粗隆顶点局部骨折复位固定26例（复位组）,未复位固定20例（未复位组）。比较2组手术时间、术中出血量、术后第2天血红蛋白及白蛋白水平、骨折愈合时间、术后并发症及末次随访时髋关节功能Harris评分。结果复位组较未复位组手术时间更长、术中出血量更多,差异有统计学意义（P〈0.05）;但复位组在术后并发症及末次随访时髋关节的功能恢复方面明显优于未复位组,差异有统计学意义（P〈0.05）;而2组在骨折愈合时间、术后第2天血红蛋白及白蛋白水平方面差异无统计学意义（P〉0.05）。结论复位固定移位的股骨大粗隆顶点骨折能够提高PFNA主钉进针定位的准确性,降低股骨大粗隆外侧壁继发性骨折的发生率,改善术后髋关节功能,减少术后隐性出血量。     

股骨干骨折交锁髓内钉内固定术后的护理

目的 探讨交锁髓内钉内固定术后的护理方法和效果.方法 将96例股骨干骨折行交锁髓内钉内固定术后的患者随机分为两组,对照组48例按术后常规护理,实验组48例在常规护理的基础上,增加患肢蜡疗联合TDP神灯照射疗法,观察并记录术后1周内并发症及护理问题.结果 术口疼痛Ⅱ度以上对照组33例,实验组12例;术口水肿（＋＋）以上对照组33例,实验组12例;两组患者在术口疼痛、水肿、感染及深静脉血栓等方面比较差异具有统计学意义（P＜0.05）.结论 蜡疗联合TDP神灯照射疗法,对预防交锁髓内钉内固定术后水肿、疼痛等护理问题效果显著,对预防术后感染、深静脉血栓等护理无影响.     

TEIN治疗儿童桡骨颈骨折的临床观察

目的：探讨钛制弹性髓内钉（titanium elastic intrameduary nail, TEIN）在儿童桡骨颈骨折中的临床疗效。方法2009年1月~2011年6月共收治JudetⅢ型和Ⅳa型的儿童桡骨颈骨折12例,应用TEIN进行复位固定。术后石膏支具固定3周,石膏支具拆除后进行功能锻炼。结果12例患者骨折均愈合良好,无畸形,在随访期无桡骨头过度生长、桡骨头缺血坏死及桡骨头骨骺早闭。根据Tibone和Stoltz功能评价标准,优10例,良2例。无并发症发生。结论 TEIN在治疗儿童桡骨颈骨折中具有创伤小、操作简便、恢复快、并发症少及美观性强等优点,值得临床推广应用。     

交锁髓内钉合侧方钢板内固定与可桥接钢板内固定治疗下肢骨干无菌性骨不连的临床效果对比研究

目的 比较交锁髓内钉合侧方钢板内固定治疗与可桥接钢板内固定治疗下肢骨干无菌性骨不连的临床效果.方法 随机选取2011年10月～2013年11月在本院骨科手术治疗下肢骨干无菌性骨不连手术的256例患者为研究对象,根据治疗方法不同分成两组,交锁髓内钉组142例采用交锁髓内钉合侧方钢板内固定治疗,可桥接钢板组114例采用可桥接钢板内固定治疗,对比两组的围术期及术后随访情况.结果 术后256例患者骨折愈合且无并发症.交锁髓内钉组出血量和引流血量多于可桥接钢板组,内固定时间、临床愈合时间、影像愈合时间、住院时间长于可桥接钢板组,手术时间短于可桥接钢板组,骨痂评分低于可桥接钢板组,住院费用高于可桥接钢板组,差异均有统计学意义（P＜0.05）.结论 两种下肢骨干骨不连的临床治疗方法均取得较好疗效,临床医生可根据患者的既往创伤程度、经济水平以及医院现有技术等综合考虑,选择最有利的治疗方式.     

INTERTAN髓内钉与滑动髋螺钉治疗老年性粗隆间和粗隆下骨折的临床效果比较

目的：研究INTERTAN髓内钉与滑动髋螺钉(DHS)治疗老年性粗隆间和粗隆下骨折的效果。方法选取2012年1月~2014年1月在本院进行治疗的老年粗隆间和粗隆下骨折患者80例,按照随机数字表法分为髓内钉组40例和髋螺钉组40例。比较两组患者的术中出血量、术后引流量、手术时间等,术后3、6个月分别进行视觉模拟评分(VAS)。结果两组手术时间差异无统计学意义(P>0.05);髓内钉组术中出血量和术后引流量明显少于髋螺钉组,差异有统计学意义(P<0.05)。两组患者术后3、6个月VAS评分比较,差异无统计学意义(P>0.05)。结论髓内钉与髋螺钉治疗老年性粗隆间和粗隆下骨折,髓内钉方式优于髋螺钉方式,在术后恢复、并发症方面两种方式并无明显差异。     

髓内钉和钢板内固定治疗胫骨远端关节外骨折的效果分析

目的：比较髓内钉和钢板内固定治疗胫骨远端关节外骨折的效果。方法选取本院的64例胫骨远端关节外骨折患者作为研究对象,随机分成A组和B组,各32例。A组选择髓内钉内固定治疗,B组选择钢板内固定治疗,比较两组的治疗效果。结果 A组的手术时间为（93±24）min,B组的手术时间（84±12）min,两组比较差异无统计学意义（t=1.90,P=0.067）。 A组的术后踝关节功能优良率为84.38%,B组的术后踝关节功能优良率为90.63%,两组比较差异无统计学意义（字2=0.57,P=0.45）。A组的骨折愈合时间为（18.6±4.2）周,B组的骨折愈合时间为（20.6±4.6）周,两组比较差异无统计学意义（t=1.82,P=0.079）。 A组的畸形愈合率显著高于B组,差异有统计学意义（P<0.05）。A组的延迟愈合率与B组比较,差异无统计学意义（P>0.05）。结论髓内钉和钢板内固定治疗胫骨远端关节外骨折的效果相当,术式选择需根据患者具体情况制订。     

A new way to treat forearm post-traumatic non-union in young patients with intramedullary nailing and platelet-rich plasma

Introduction

Non-union rate in forearm fractures is generally less than 2% when a proper technique is used; this rate increases when ulnar lesions are involved.

Patients and methods

We present a case series of seven young patients whose average age was 14 years (range 11–19 years) at the time of surgery and who presented with a forearm post-traumatic non-union that was previously treated in different ways (three isolated ulnar non-union, two isolated radial non-union and two combined). Average follow-up was 34 months (range 9–72 months).Surgical treatment began with the removal of the previous synthesis and with curettage of the non-union area. The Acumed ulnar rod, Acumed radial rod and Thalon elastic nail (all of them are unreamed and locked nails) together with autologous platelet-rich plasma (PRP) obtained with the Biomet System (concentration of 158.2 × 10⁴ platelets/μL) were chosen to treat the patients.X-rays and clinical controls were conducted every 30 days until recovery.

Results

All patients recovered: average recovery was 23 weeks from operation (range 16–36 weeks) and nails were removed 3 months after complete healing. Six patients had excellent results and one patient had a good result (Patient 2, forearm pronosupination 60–0–40 degrees).

Discussion

The purpose of the case series was to establish a better way of treatment and to find a technique that could avoid the use of bone grafts, because obtaining autologous bone requires a further surgical procedure that can be really invasive depending on the amount of bone needed.

Conclusion

All patients in the study showed complete recovery, with excellent clinical outcomes. Although there were only seven patients in this case series, and there is a need to analyse more patients, this study showed that the use of a specific locking nail system can provide proper stability to ulnar or radial atrophic non-union despite rotational forces, and when combined with autologous growth factors (PRP) is sufficient to promote bone healing in young patients without the necessity to take autologous bone grafts.     

Femoral malrotation after intramedullary nailing in obese versus non-obese patients

Objective

Intramedullary nailing (IMN) of obese patients with femoral fractures can be difficult due to soft tissue considerations and overall body habitus. Complications including malrotation can occur and have significant impact on postoperative function. The purpose of this study was to evaluate femoral rotation after intramedullary nailing of obese and non-obese patients to see if there was a difference in rotation, complications and any risk factors for malrotation.

Materials and methods

Between 2000 and 2009, 417 consecutive patients with femur fractures treated with IM nail at Level I trauma and tertiary referral center. Of these, 335 with postoperative computed tomography (CT) scanogram of the bilateral lower extremities were included in this study. Baseline demographic, perioperative and postoperative femoral version calculations were included in the dataset. Statistical analysis included chi-squared test for categorical data, t-test for continuous data, and univariate and multivariate regression analysis. Significance was set at p < 0.05.

Results

Of the 417 patients with femur fractures between 2000 and 2009, 335 met criteria for this study. There were 111 patients with a BMI <25, 129 with BMI 25–29.9, and 95 patients with a BMI >30. When BMI was categorised into 3 groups (<25, 25–29.9, or 30+), none of these groups were predictive of version in univariate or multivariate regressions. Among only obese patients (BMI 30+), BMI of 35+ was not a significant predictor of version when compared to BMI 30–34.9. There were no significant differences in femoral version based on entry point (antegrade vs. retrograde) in any BMI category. There were also no significant difference between groups of patients with a DFV of >15? (p = 0.212).

Conclusions

Based on this study, BMI did not have an effect on postoperative difference in femoral version. In fact, in our multivariate regression analysis, BMI of over 30 was actually predictive of significantly lower difference in femoral version. While other studies have documented the intraoperative difficulties encountered with obese patients with femur fractures, the outcome of femoral rotation is not affected by an increasing BMI.     

Risk of injury to the axillary nerve during antegrade proximal humeral blade nail fixation – An anatomical study

Introduction

The antegrade intramedullary Locking Blade Nail (Marquardt, Germany) is a device aimed at improving purchase in the humeral head and reducing varus displacement by providing medial buttress support and triangular stability within the humeral head. The aim of this study is to measure the relationship of the proximal fixation screws to the axillary nerve.

Methods

13 whole cadavers underwent insertion of an antegrade proximal humeral blade nail via a deltoid split approach to both shoulders. The anatomic proximity of the anterior branch of the axillary nerve to the screws was measured following soft tissue dissection and inspection of the nerve.

Results

The mean distance of the nerve from the anterolateral acromion was 62 mm (range 45–81 mm). The nerve lay closest to the distal blade fixation screw 4.9 mm (range 0–19 mm). In three cases the nerve lay directly underneath the washer and in all three cases there was macroscopic evidence of damage to the nerve. In 5 cases the nerve travelled obliquely in a cranial direction to lie 1.8 mm (range 0–3 mm) from the distal blade fixation screw, in 2 of these cases the nerve lay beneath the washer.

Conclusion

The anterior branch of the axillary nerve is placed at risk during insertion of the locking screws despite use of protection sleeves and trocars. We advocate that when using antegrade intramedullary nails that incorporate an inferomedial calcar screw an extended anterolateral acromial approach is undertaken.