What is the detailed step‑by‑step procedure for intramedullary nailing of a mid‑shaft tibial fracture using a solid tibial nail inserted through the lower pole of the patella?

Intramedullary Nailing of Mid-Shaft Tibial Fracture via Suprapatellar Approach

For a mid-shaft tibial fracture, perform solid tibial nail insertion through a suprapatellar portal with the patient supine and knee semi-extended, which provides superior access, reduces anterior knee pain, and minimizes radiation exposure compared to traditional infrapatellar approaches. 1, 2

Patient Positioning and Preparation

• Position the patient supine on a radiolucent operating table with a bump placed under the ipsilateral hip to facilitate alignment 1
• Keep the knee in semi-extended position (not flexed over a triangle as in traditional infrapatellar technique) to counteract procurvatum deformities, particularly important for proximal third fractures 2
• Ensure adequate fluoroscopic visualization in both AP and lateral planes before draping 1

Surgical Approach and Entry Point

• Make a 4 to 6-cm longitudinal incision 2 to 4 cm directly proximal to the superior pole of the patella (not at the lower pole as stated in your question—the lower pole reference likely means the approach goes through the patellofemoral joint inferior to the patella's articulation) 1
• Sharply incise the quadriceps tendon at its midline and split it longitudinally in line with its fibers 1
• Insert a cannula device with blunt trocar and protective sleeve into the knee joint, positioning it between the patellar articular surface and the femoral trochlea 1
• Place a second stabilizing pin through the cannula into the distal femur to prevent the cannula from backing out during the procedure 1

Critical Pitfall

Be aware that this approach causes definitive scuffing of cartilage in the lower femoral trochlea, though clinical patellofemoral symptoms are uncommon 3

Establishing the Starting Point

• Insert a 3.2-mm guide pin through the cannula and position it at the junction of the articular surface and anterior cortex of the tibia, aligned with the intramedullary canal 1
• Advance the guide pin 8 to 10 cm into the proximal tibia 1
• Remove the inner centering sleeve and pass the cannulated entry drill over the pin through the outer protective sleeve 1
• Ream down to the metadiaphyseal level of the proximal tibia to create the entry portal 1

Fracture Reduction and Guidewire Passage

• Achieve fracture reduction using manual manipulation or reduction clamps as needed 1
• Pass a ball-tipped guidewire centrally across the fracture down to the level of the distal tibial physeal scar 1
• Confirm proper guidewire position in both AP and lateral fluoroscopic views before proceeding 1

Reaming and Nail Insertion

• Perform incremental reaming over the guidewire, typically starting 0.5-1.0mm larger than the guidewire and increasing in 0.5mm increments 1
• Select nail diameter based on final reamer size (typically 1-1.5mm smaller than final reamer for solid nails) 1
• Insert the appropriately-sized solid tibial nail down the tibial canal over the guidewire 1
• Advance the nail until proper position is achieved with the proximal end seated at the appropriate depth 1

Interlocking Screw Placement

• Confirm appropriate nail position radiographically in both planes before locking 1
• Place distal interlocking screws first using freehand technique under fluoroscopic guidance 1
• Attach the proximal aiming arm to the insertion handle 1
• Drill, measure, and place proximal interlocking screws through the aiming device 1
• Verify all screw positions fluoroscopically to ensure bicortical purchase without articular penetration 1

Closure

• Close the quadriceps tendon split with absorbable suture in a running or interrupted fashion 1
• Close subcutaneous tissues and skin in standard layered fashion 1
• Apply sterile dressing and consider knee immobilizer for initial comfort 1

Timing Considerations

In hemodynamically stable patients without severe visceral injuries, perform definitive intramedullary nailing within the first 24 hours to reduce local and systemic complications, particularly respiratory complications, ARDS, and fat embolism syndrome 4

However, if the patient has severe visceral injuries (brain, thorax, abdomen, pelvis, spinal cord), circulatory shock, or respiratory failure, delay definitive fixation and perform temporary stabilization with external fixator or skeletal traction first 4. Once clinically stabilized, proceed with definitive nailing as early as safely possible 4.

Rationale for Early Fixation

Early definitive osteosynthesis of tibial shaft fractures within 24 hours reduces the incidence of both local and systemic complications in stable patients, allowing earlier mobilization and reducing hospital stay 4, 5

Postoperative Management

• Allow early postoperative ambulation as this load-sharing device provides sufficient biomechanical stability 1
• Most fractures achieve union by 9 weeks with this technique 6
• Monitor for complications including infection (3.5% deep infection rate in complex cases), malunion, and hardware issues 7

Common Complications to Monitor

Open fractures have 5.5 times higher complication rates compared to closed fractures and significantly longer union times 8. Patient body weight also correlates with healing—heavier adolescents show lower radiographic union scores at 12 weeks 8.