Modification of electrostatic charge on inhaled carrier lactose particles by addition of fine particles.

Triboelectrification affects particle adhesion and agglomeration and hence the formulation, manufacture, and use of dry powder inhaler (DPI) devices. Electrostatic charge measurement of two component mixes of spray-dried or crystalline lactose fine particles (< 10 microns) 0, 5, 10, 15, 20, and 30% w/w with spray-dried or crystalline lactose 63-90 microns, respectively, has been undertaken using a system incorporating pneumatic transport of the mixed powders to a stainless steel cyclone charging device. The magnitude of charge on the mixes was shown to decrease with increased fine particle content, and there was no significant difference in charge for each concentration between spray-dried and crystalline lactose. Both the variation of charge and powder adhesion to the cyclone surface increased with increase in fine particle content. The proportion of fine particles in carrier systems in DPIs may thus have an important role where triboelectrification is involved.

Initial experience with the treatment of supracondylar femoral fractures using the supracondylar intramedullary nail: a preliminary report.

Initial experience at a Level I Trauma Center with the use of a retrograde supracondylar intramedullary (IM) nail for the treatment of supracondylar and supracondylar-intercondylar intraarticular fractures of the distal femur is presented. Thirty-eight patients with 41 complex distal femur fractures were treated with this newly developed retrograde IM rod. These included 22 open fractures and 19 closed fractures. Four nonunions occurred, but all progressed to union after revision internal fixation and bone grafting. Two of five delayed unions required revision fixation. Two required screw renewal and dynamization. Thirty-five of 41 knees achieved at least 90 degrees of knee motion. There were no infections and no problems with wound healing. Four patients developed fatigue fractures of the rod. These mechanical failures occurred when 11- and 12-mm nails were used in conjunction with 6.4-mm interlocking screws. The rod system was therefore modified to include 12- and 13-mm diameter nails and smaller 5.0-mm interlocking screws. There have been no subsequent nail failures. We are cautiously optimistic that supracondylar IM rod fixation will contribute to the management of these difficult fractures. However, further clinical trials and additional biomechanical testing should be undertaken prior to widespread use of this device.

False aneurysm of the medial inferior genicular artery after intramedullary nailing of the tibia.

Although rare, arterial false aneurysm about the knee has been a well-documented complication of many types of surgery. False aneurysms have been reported after such procedures as open meniscectomy, synovectomy, arthroscopy, total knee arthroplasty, and proximal tibial osteosynthesis. Arteries injured in these procedures have included the popliteal artery and the descending, medial superior, medial inferior, lateral superior, and lateral inferior genicular arteries. An extensive review of the literature showed no cases of false aneurysm after intramedullary nailing of the tibia.

Ipsilateral hip and femoral shaft fractures.

Forty-two cases of ipsilateral hip and femoral shaft fractures are reviewed. All patients were treated operatively for both fractures, with the exception of the shaft fracture in one child. Several different methods of fixation were used. The most common method was placement of multiple pins or screws around a previously placed intramedullary rod. Initial rodding of the shaft was not associated with avascular necrosis of the femoral head. Nonunion of the femoral neck occurred in three patients as a result of initial displacement and subsequent malreduction. Delays in operative fixation up to six weeks did not affect the ability to obtain union of the femoral neck. Complications involving the shaft fracture were at least as common as complications involving the femoral neck, suggesting that this component of the double injury should receive equally serious consideration. The hip fracture was initially overlooked in 13 cases (31%) without subsequent nonunion or avascular necrosis. Overall, the prognosis with regard to healing of the femoral neck and avascular necrosis of the femoral head in these combination injuries was found to be superior to that of isolated femoral neck fractures in young adults.