摘要:

SummaryIntramedullary fixation devices (IMFDs) function as load‐sharing devices. This favorable biomechanical situation is achieved when a properly placed IMFD restores axial alignment of the fracture and allows return of some of the load‐bearing capacity of the bone. Load sharing can be achieved in withstanding compressive, bending, and torsional loads. The performance of an IMFD is related to the curvature mismatch and contact length between the intramedullary device and the intramedullary canal, and this can be directly affected by the starting point from which the IMFD enters the intramedullary canal of the long bone. Furthermore, the performance of an IMFD is directly related to the structural properties of these devices, including stiffness and strength. These properties are derived from various combinations of materials and design geometry. Reaming the intramedullary canal has direct biologic effects on the blood supply to the long bone. The fit and cross‐section geometry of the IMFD play an important role in the regeneration of this blood supply and therefore in fracture healing. The ability to interlock IMFDs, although providing a favorable biomechanical construct that allows load sharing and enhanced fracture stability, has the increased risk of fatigue failure because of notch sensitivity at the screw holes. The proper selection and use of these intramedullary devices, based on an understanding of both the biology and mechanics of these implants, can help the surgeon achieve excellent results even in complex fracture patterns.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryThe successful use of small‐diameter rods for stabilizing long‐bone fractures has raised the question of the necessity of medullary reaming. Recent sporadic reports in the literature13,15of osteonecrosis, believed to be a direct result of reaming of the medullary canal, pose the following questions: Is the act of reaming the culprit or are the reamers themselves significant contributors to the problem? Can design changes create a safer method of canal preparation both locally and systemically?4,5,7,11,16,19,26,27

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryThe indications for tibial nailing are evolving and expanding from diaphyseal fractures to include proximal, distal, and open fractures. The biologic and mechanical advantages of intramedullary (IM) nail fixation, as well as the increasing number of surgeons who have become proficient in the technique, are the impetus for extending the indications of this technique. Nailing of proximal tibial fractures represents perhaps the most demanding indication. The correct use of nailing in these fractures requires a great deal of surgical experience. To achieve good results in proximal fractures, the surgeon must be proficient at conventional IM nailing and be able to expand on routine nailing techniques appropriate for diaphyseal fractures. Because of the inherent difficulties of nailing proximal fractures, less experienced surgeons may prefer to continue stabilizing these fractures by other methods. Anyone who wants to use nailing for the treatment of proximal tibial fractures must appreciate the unique characteristics of this procedure. Failure to master these techniques will lead to less than optimal results, which has been evidenced by a reported high incidence of malunion.1In this article, the advantages and pitfalls of nailing proximal tibia fractures are summarized and strategies developed to address the surgical problems associated with the application of this technique.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryRetrograde nailing has been effective in patients with multiple system injuries or multiple fractures. This technique is performed on a radiolucent operating table to ensure full fluoroscopic visualization. For axially stable injuries, manual traction is sufficient to reduce the fracture and to allow nailing. Fractures with extensive comminution and axial instability often require application of a femoral distractor. Insertion can be accomplished through a small midline patellar ligament splitting approach. A cannulated entry portal reamer facilitates the correct nail entry hole. Proximal interlocking is undertaken using a simple freehand technique. Using a design‐specific femoral nail for retrograde insertion, which incorporates the concepts of canal fill and early dynamization, our rate of union for this technique approaches 94% with time to union of approximately 12.6 weeks. No symptoms of knee pain or dysfunction have been attributed to the nail insertion site. This technique is not advocated for replacement of antegrade techniques, but can be an additional tool used to facilitate the care of certain patients by allowing shorter operating room time setup, decreased blood loss, and avoidance of the use of the fracture table.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryIntramedullary nailing of humeral shaft fractures is still a controversial issue. The comments and experience with antegrade nailing vary from enthusiasm to criticism. Main criticisms concern the damage of the rotator cuff and articular cartilage and possible impingement syndrome. The new unreamed humeral nail (UHN) is being used for antegrade and retrograde insertion. We describe the technique of retrograde nail insertion. The nail is 6.7, 7.5, or 9.5 mm. It has one curvature of 4° at the transition proximal to second fourth. There are three interlocking possibilities at the nail base and nail tip. Interfragmentary compression is achieved through a compression device. The entry portal for nail insertion is situated above the olecranon fossa; the elbow capsule is not opened. The occurrence of a supracondylar fissure or fracture and secondary damage to the radial or axillary nerve are the most feared complications. In a series of 190 retrograde nailings, the most frequent intraoperative problems were fissure or avulsion at the entry portal (n = 8; 4.2%) and secondary radial nerve palsy (n = 8; 4.2%). All radial nerve palsies recovered spontaneously. Sixty‐eight patients were followed up until fracture healing. There were five (7.4%) bone healing problems. Four of five could be solved with the use of the unreamed humeral nail in a second operative procedure, whereas the fifth required plate osteosynthesis. Function of the shoulder and elbow joint was excellent in 89.7% and 88.3% of the patients, respectively. The UHN is a valuable addition to the implants, available for operative treatment of fresh or pathologic humeral shaft fractures. Retrograde humeral nailing is a safe and reliable procedure if done properly. Bone healing problems after unreamed humeral nailing must be analyzed individually, but they can be treated with the same implant in combination with cancellous bone grafts, reaming, additional hardware, or intrafragmentary compression.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryA method of closed femoral unlocked nailing using ultrasound instead of the image intensifier for assessment of the fracture alignment in several steps from beginning to end is described. In a prospective study of this method in 102 cases of unilateral femoral shaft fracture, 92 procedures were successfully performed with this technique. The time required for the reduction of the fracture until the guide wire could be inserted into the distal fragment averaged 7.3 minutes (range, 1‐14 minutes). The overall operation time averaged 40 minutes (range, 25‐60 minutes). Of 10 failure cases, three were the result of soft‐tissue interposition that required open reduction, four were the result of the fractures being unable to be reduced within 15 minutes of trial, two required fluoroscopic assessment because the guide wire could not be inserted into the distal fragment, and one required fluoroscopic monitoring during insertion of the nail because of impending incarceration of the nail. The method had been effective in 92% of cases with simple or minimal comminuted femoral shaft fractures that underwent closed unlocked nailing.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryMany different mechanisms have evolved over the years for targeting distal femoral screw holes. Nearly all of these techniques are x‐ray dependent. We describe the first practical use of magnetic distal targeting to accurately target distal screw holes. The procedure involves the use of neodymium‐iron‐boron magnets, which are placed at the level of the distal screw holes to be targeted, and the accurate placement of a cannulated guide wire by use of a free‐floating balanced magnet encased in a soft tissue protector. Once magnetic alignment has been achieved, a compass drive advances a 1.6‐mm Steinmann pin into the outer cortex of the bone. The target magnet is withdrawn up the femoral canal and a cannulated drill is used to overdrill the guide wire to prepare the screw hole within the intramedullary nail. The length is measured and the screw is inserted. This technique has proven to be accurate with first‐time users, and in surgical situations, it reduces x‐ray exposure and operative time.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryThis article outlines our experience with a new technique using a radiolucent fracture support for intramedullary nailing procedures. The support is used primarily for nailing of acute tibial shaft fractures and for insertion of femoral nails in a retrograde fashion without a fracture table.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID

摘要:

SummaryLower‐extremity long bone fractures are often managed with intramedullary implants. Traditional nailing techniques using fracture tables involve prolonged set‐up times. Procedures performed without fracture tables are increasing in popularity but present additional challenges. Fracture movement must be controlled to avoid additional soft tissue damage. Control of fracture length and rotation is prerequisite as is the need for changes in angular position of the knee during surgery. Ancillary intraoperative stabilization and extra skilled assistants are frequently required. The Knee Positioning Triangle, a rigid, free‐standing, radiolucent appliance, provides a stable operating platform through a range of angular positions during tibial and retrograde femoral intramedullary nailing procedures. Operative set‐up times are abbreviated and extra assistants are not required.

ISSN:0885-9698    

出版商:OVID    

年代:1998

数据来源: OVID