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Case: A 75-year-old man underwent intramedullary nailing for an unstable intertrochanteric fracture of the left hip. After surgery and postoperative recovery, he was transferred to a rehabilitation ward. He was able to mobilize at 2 days postoperatively; at 2 weeks postoperatively, he developed the sudden onset of tachycardia, hypotension, and a large hematoma on the left thigh. Following immediate resuscitation, a computed tomography (CT) angiogram demonstrated a bleed from a branch of the profunda femoris artery. The 3-dimensional CT reconstruction implicated the displaced lesser trochanter osseous fragment as the cause of the hemorrhage., Conclusion: Surgeons should be aware of this rare complication and the possible etiology of fracture displacement as the cause of a delayed-onset bleed after intramedullary nailing, and they should also be cognizant of the subsequent optimal management.

It was hypothesized that transverse locking screws of intramedullary nails, seated above the lesser trochanter, provide equal strength to that of reconstruction nails, and that screws placed through the medial cortex of the femoral neck do not have adverse biomechanical effects during physiologic loading. Synthetic femurs (n = 10) and paired anatomic specimen femurs (n = 14) were tested intact and with an intramedullary device in place. Intact specimens were loaded nondestructively, then a segmental subtrochanteric defect was created and either a high seated transverse locking nail or a reconstruction nail was inserted and statistically locked. Axial and torsional stiffness were determined followed by axial failure testing. Mechanical parameters evaluated were stiffness, displacement, and energy. The implanted specimens did not show any statistically significant difference between transverse or reconstruction screw constructs with any of the measured parameters (stiffness, displacement, and energy). Failure tests in implanted specimens also did not show any statistically significant difference in yield load, yield displacement, or energy to failure between implant constructs. All anatomic specimens failed, with fractures of the proximal fragment involving medial and lateral cortices. Synthetic specimens did not fracture but showed failure with implant deformation at the level of the skeletal defect. The use of high seated transverse locking nails for complex proximal femoral fractures is a viable option and has comparable in vitro mechanical performance with reconstruction nails. Although not shown to be a problem in the present study, clinical evaluation of screws through the medial femoral neck cortex is required.

A sheep model was developed for the implantation of 84 bicylindrical stainless steel external fixation pins. One-half of the pins were coated with hydroxyapatite, and the rest remained uncoated. A set of 6 pins with the same coating was implanted in the lateral side of the left tibias of 14 sheep, the final insertion torque was measured, and a monolateral external fixator was assembled on the pins. The medial tibial middiaphysis then was exposed and a 5-mm resection osteotomy was done. Sheep were euthanized 6 weeks after surgery, radiographs were taken, and the initial extraction torque was measured on 4 pins from each sheep. Undecalcified sectioning and histologic and histomorphometric analyses were done on the remaining 2 pins. Radiographic pin tract rarefaction was significantly lower in the hydroxyapatite coated pins compared with the uncoated pins. Group average insertion torque was 960 +/- 959 Nmm in the hydroxyapatite coated pins and 709 +/- 585 Nmm in the uncoated pins. Group average initial extraction torque was 1485 +/- 1308 Nmm and 298 +/- 373 Nmm, respectively. Bone pin contact was 85.7% +/- 8.9% and 50.3% +/- 20.4%, respectively, in hydroxyapatite coated and uncoated pins. Bone between the threads was 95.6% +/- 5.7% and 80% +/- 8.7%, respectively, in hydroxyapatite coated and uncoated pins. Hydroxyapatite coating was effective for improving the bone-to-pin interface.

The biomechanical properties of commercially available locked nail systems designed for use in comminuted femoral shaft fractures were compared and evaluated. Ender nails as well as three forms of interlocking nails, Brooker-Wills (B-W), Klenm-Schellman (K-S), and Grosse-Kempf (G-K), were implanted in cadaver femora. The femora were tested in torsion, bending, and axial loading to failure. Two fracture models were tested--a 3 cm subtrochanteric defect and an 8 cm midshaft defect. Results of the testing revealed the three interlocking nails to be comparable to each other and superior to Ender nails in bending and torsion. However, the distally bolted locked nails (K-S, G-K) resisted significantly higher loads than either the distally bladed locked nail (B-W) or Ender nails when tested to failure by axial loading.

Twenty cases of nonunion of forearm fractures were treated by the Küntscher method of intramedullary reaming and nailing. Fifteen fractures healed per primam; 2 required renailing; 2 did not heal but the patients benefited from the stabilizing effect of the nail; 1 was lost to follow-up. Even infected cases could be treated successfully by this method, but extensive experience with all the details of the surgical technique may constitute the difference between catastrophic failure and success. Excision of sinus tracts and sequestrectomy were done as a preliminary procedure.

While intramedullary fixation may have less operative morbidity than sliding plate systems, there also may be a loss of stability and strength of the fixation. In a biomechanical study with simulated unstable intertrochanteric fractures in cadaver femurs, multiple Ender's pins were 18% stronger than the single Harris nail. Compression hip screws were three times stronger than the Harris nail and two and one-half times stronger than Ender's pins. The compression hip screw was five times more rigid than either condylocephalic system.