Intramedullary Nailing of Lower-Extremity Periarticular Fractures.

Intramedullary nailing is used to stabilize distal femoral, proximal tibial, and distal tibial periarticular fractures with short proximal or distal segments, as well as some intra-articular fractures in which a stable articular block can be created. Intramedullary nailing may be beneficial in complex fracture patterns with diaphyseal extension, segmental injuries, or patients who might benefit from a decreased incision burden. Step 1: Preoperative planning. Review imaging and make sure there is a nail with adequate interlocks. Consider the use of adjunctive techniques to obtain and maintain alignment, and how intra-articular fracture lines will be stabilized. Step 2: Position and prepare the patient. Step 3: Exposure for nailing via suprapatellar, infrapatellar, or knee arthrotomy approaches. Limited exposure of fracture planes may also be necessary for adjunctive techniques. Step 4: Convert an OTA/AO C-type fracture to an A-type fracture if needed. Step 5: Obtain appropriate starting point and trajectory with the nail starting wire and use the opening reamer. Step 6: Obtain reduction, if not yet done, and pass the ball-tipped reaming wire across the fracture. Step 7: Ream while holding reduction. Step 8: Pass nail. Step 9: Verify reduction is maintained and correct if needed. Step 10: Place interlocks, preferably multiplanar, in the short segment. Create a fixed angle construct if desired and convert adjunctive techniques/provisional fixation to definitive fixation as needed. Step 11: Perform final checks. Step 12: Closure. Step 13: Postoperative plan. For extra-articular fractures, one may expect healing with maintained alignment from what was present at the case end intraoperatively in the vast majority of cases. For intra-articular fractures, development of posttraumatic arthritis is an additional concern.

Healing of rat femoral segmental defect with bone morphogenetic protein-2: a dose response study.

OBJECTIVE: Use of recombinant human bone morphogenetic protein-2 (rhBMP-2) is becoming a common clinical approach to enhance bone repair. There is little or no information in the literature on the dose of rhBMP-2 required for effective healing of critical-sized defects such as those associated with trauma. In this study, we used a segmental defect model to assess the dose response of rhBMP-2 using quantitative and qualitative endpoints. METHODS: Femoral defects in rats were replaced with absorbable collagen sponges carrying rhBMP-2 (0, 1, 5, 10 or 20 µg; N=5). At 4-weeks new bone formation was assessed using quantitative (radiography and microcomputed tomography) and qualitative (histology and backscattered-SEM) endpoints statistically compared. RESULTS: rhBMP-2 showed increased bridging in the gap. Quantitative evaluation presented a bi-phasic dose response curve. Histological assessment revealed that with rhBMP-2 the defect showed the presence of spongy bone with the trabeculae layered with active osteoblasts and osteoclasts. The density and compactness of the bone varied with the dose of rhBMP-2. CONCLUSIONS: Our findings revealed that all doses of rhBMP-2 result in new bone formation. However, there is an optimum dose of 12 µg of rhBMP-2 for bone repair in this model, above which and below which less stimulation of bone occurs.

Intramedullary nailing of the femur: reamed versus nonreamed.

All intramedullary nailing creates some loss of endosteal blood supply and an increase in intramedullary pressure, resulting in marrow embolization. In laboratory studies, both reamed and nonreamed intramedullary nailing have led to alteration in selected pulmonary variables. This effect, although transient, appeared more pronounced with reamed techniques than with nonreamed techniques. Concern about the systemic pulmonary effects of reamed intramedullary nailing has led to an increase in the use of nonreamed nailing. The authors of most clinical studies have reported that reamed intramedullary nailing has not been associated with a concomitant increase in pulmonary complications in multiply injured patients, although this point is still controversial. Femoral shaft fractures treated with nonreamed nailing have been shown to have slightly higher rates of delayed union and nonunion compared with those treated with reamed nails. Reamed interlocking intramedullary fixation remains the treatment of choice for femoral shaft fractures in adults. Further study is required to determine whether an identifiable subgroup of trauma patients is adversely affected by intramedullary reaming, which would suggest the need for alternative fixation techniques.