A novel technique for femoral canal occlusion during cement pressurization in proximal femoral arthroplasty

We describe a novel technique for occluding the femoral canal distal to the isthmus during proximal femoral arthroplasty. Synthetic bone models were reamed and sectioned to simulate loss of the proximal femur. Two experimental conditions were used. The first used no restrictor to act as a control. The second used calcium sulphate pellets impacted in distal femoral canal. A 100 × 12 mm Limb Preservation System stem (DePuy, Leeds, UK) was used in all experiments. We recorded cement pressure, leakage of cement, and penetration of cement into the femoral condyles. The calcium sulphate pellets prevented cement leakage, enabled higher cementing pressures, and prevented penetration of the cement into the femoral condyles. We would recommend this technique in cases where loss of proximal femoral bone loss requires the use of a cemented proximal femoral replacement.     

Histological findings of the femoral bone after cement removal in hip revision

Cement removal in hip revision arthroplasty is often a time-consuming procedure, lengthy and tedious. Intraoperative bone damage is one of the more common complications. In the present study, the conventional cement removal method is compared with a new method by means of a histological study concerning potential negative effects to cortical or spongious bone. Histological studies on human cadaver femurs demonstrate no deleterious effects on the endosteal bone when cement was removed with this new device. The ballistically driven chiselling system (OrthoClast) is safe to the bone stock and shows no increased risk of bone damage over the conventional technique with mallet and chisel.     

A novel method of removal of a broken drill bit in the femoral medullary canal during internal fixation of a type C distal femoral fracture: a case report

Breakage of surgical instruments and implants during operative procedures is not uncommon in any surgical discipline.The need for removal and the outcome of leaving the broken instruments and implants ...     

Arthroscopic removal of acrylic cement from unreduced hip prosthesis.

A case is reported in which entrapped polymethylmethacrylate following traumatic dislocation of a total hip replacement prevented complete reduction. A combined arthroscopic and fluoroscopic technique was used to remove the entrapped polymethylmethacrylate. Manipulation of the total hip prosthesis was done after removal of polymethylmethacrylate to minimize mechanical abrasion. This technique allows direct visual assessment of the articulating surfaces as well as the mechanical stability of the prosthesis. The morbidity related to the procedure is minimal and a short rehabilitation period is the major advantage.     

Removal of bone cement from the femoral shaft using a femoral windowing device

The authors previously described a method of windowing the femur that allowed good exposure for femoral cement removal and provided for reconstruction of the defect. Since that report, they have developed instrumentation to facilitate windowing of the femoral shaft. They describe its use in this report.     

股骨皮质骨开窗技术在髋关节翻修术中的应用

目的 探讨股骨前外侧皮质骨开窗技术在髋关节翻修术中取出股骨远端稳定固定骨水泥的价值.方法 2005年5月至2009年6月,共14例(14髋)因各种原因致髋关节置换术后失败患者接受全髋关节翻修手术.其中男性10例,女性4例,年龄54～75岁,平均66岁.翻修原因为股骨头置换术后髋臼磨损5例、全髋关节置换术后假体周围骨溶解并松动6例、骨水泥柄股骨近端骨溶解柄断裂1例、髋臼骨溶解假体松动翻修同时行股骨柄翻修1例,感染后二期翻修时远端骨水泥取出困难1例.14例(14髋)股骨柄均为骨水泥同定.术中按术前计划开窗部位、开窗范围于股骨皮质骨开一长方形骨窗.通过骨窗直视下彻底清除髓腔内稳定固定的骨水泥,修整股骨髓腔.植入翻修柄后将皮质骨开窗骨瓣原位回植,双股钢丝捆绑固定.术后定期随访拍摄x线片.观察皮质骨开窗骨瓣与周围骨愈合情况、骨瓣有无移位、股骨柄有无下沉以及有无捆绑钢丝断裂等.结果 10例患者术后获得随访,平均随访时间24.6个月.股骨皮质骨开窗长度2.5～6.0 cm,平均3.4 cm,宽度0.8～1.4 cm,平均1.2 cm.股骨开窗远端以远部分发生纵形劈裂骨折1例.无术中皮质骨穿孔及股骨干骨折.向远段扩大开窗1例,扩大长度1.5 cm.开窗部位皮质骨骨瓣原位回植选择2～3道双股钢丝固定,平均2.3道.随访期间2例发牛假体柄下沉(平均2.5 mm),无皮质骨瓣移位以及捆绑钢丝断裂,术后3～5个月皮质骨瓣已于周围骨纤维愈合.随访期间无一例因各种原因致再次翻修.结论 股骨皮质骨开窗技术在髋关节翻修术中有助于直视下彻底取出股骨髓腔远端稳定固定的骨水泥,同时不会造成股骨骨丢失、不影响翻修柄植入后的稳定固定.     

Calcium phosphate cement augmentation of the femoral neck defect created after dynamic hip screw removal

OBJECTIVE: To determine the effect of reinforced calcium phosphate cement augmentation of the femoral neck defect created after dynamic hip screw removal in a cadaveric model. METHODS: The lag screws of dynamic hip screw implants were inserted and subsequently removed in 8 matched pairs of cadaveric, osteoporotic femurs to create a femoral neck defect. One of each pair had the defect augmented with osteoconductive calcium phosphate cement reinforced with poly(lactide-coglycolide) fibers (Norian Reinforced, Synthes, West Chester, PA), and the other defect was not augmented. Each specimen was first cyclically loaded with 750 N vertical loads applied for 1000 cycles to simulate early weightbearing, and then loaded to failure. RESULTS: Calcium phosphate cement augmentation of the lag screw defect significantly increased the mean femoral neck failure strength (4819 N) compared to specimens in which the defect was left untreated (3995 N) (P < 0.004). The mechanism of failure for each specimen was a fracture through the femoral neck. Regression analysis demonstrated that load to failure was directly related to the bone mineral density at Ward's triangle, and the impact of cement augmentation on failure strength was greatest for specimens with the lowest bone mineral density (correlation coefficient: -0.82, P < 0.0001). CONCLUSION: This study demonstrates that augmentation of the bony defect created by dynamic hip screw removal with reinforced calcium phosphate cement significantly improved the failure strength of the bone. Cement augmentation after hardware removal may decrease the risk of refracture and allow early weightbearing, especially in elderly patients with osteoporotic bone.     

Distal femoral canal pressurization after introduction of cement restrictor plugs: an in vitro analysis

Modern cementing techniques in total hip arthroplasty routinely include the use of cement restrictor plugs to occlude the femoral canal, which enable cement containment and help in pressurized cement application. Formation of emboli from within the intramedullary canal is of great concern. We investigated the insertion force profile and distal femoral canal pressurization as a result of the introduction of different sizes of cement restrictor plugs from three different manufacturers on artificial femora. No significant difference in insertion force profiles were observed for the different restrictors tested. However, the Stryker Howmedica cement restrictor plugs generated the highest pressure in the distal intramedullary canal.     

The femoral canal: the key to femoral herniorrhaphy

It is conceded by many Authors that femoral hernias not uncommonly result from a previous inguinal herniorrhaphy. Why? A clear visualization of the femoral canal is hampered by the confusing structure of two of its components, the iliopubic tract and the lacunar ligament. Both entities have horizontal as well as vertical extensions. Therefore, a clear understanding of the femoral canal anatomy requires an appreciation of its three dimensional character. The various approaches to femoral hernia are documented. Obliteration of the entire canal by means of a "plug" prosthesis which occludes both the entrance and exit of the canal offers a simple and very effective means of correction. The results of the surgery are documented.     

The removal of porous-coated femoral hip stems.

During a ten-year period, 70 porous-coated femoral hip components of several designs were removed for various reasons. Based on this experience, techniques for the removal of porous-coated stems have evolved and are described, including a newer method for the safe removal of extensively coated bone-ingrown stems. Preoperative roentgenograms were highly predictive of fixation mode as corroborated by intraoperative mechanical testing, gross inspection, and histologic examination. Stable implants (17 bone-ingrown and 11 fibrous tissue-encapsulated) required interface access and division before their removal. Minimal bone damage was incurred, and in no case was reconstruction precluded by stem removal. There were no unplanned cortical perforations. Two minor femoral fractures occurred. The authors present an overall approach and specific surgical techniques that facilitate the safe removal of porous-coated femoral stems on a consistent basis.     

Obturator canal bypass grafts for septic lesions of the femoral artery.

Infection of the femoral artery results in false aneurysm formation and hemorrhage unless appropriate reconstructive measures are taken. We reviewed ten such cases managed by obturator canal bypass with autogenous saphenous vein. The graft maintained viability of the extremity in every case in the early postoperative period. One death occurred related to cardiac disease, and there was one late failure. This experience confirms the usefulness of the obturator canal as a method for bypass of the infected femoral artery.