What is the recommended treatment for a 12-year-old patient with an avulsion fracture of the tibial tuberosity?

Treatment of Avulsion Fracture of Tibial Tuberosity in a 12-Year-Old

Displaced tibial tuberosity avulsion fractures in a 12-year-old require open reduction and internal fixation (ORIF) to restore the extensor mechanism and prevent long-term complications. 1, 2

Initial Diagnostic Approach

• Obtain standard knee radiographs (anteroposterior and lateral views) as the initial imaging study to assess fragment size, displacement degree, and potential intra-articular extension 3
• Test active knee extension immediately—inability to actively extend the knee indicates patellar ligament avulsion, which mandates surgical intervention 4
• If patellar ligament avulsion is suspected, obtain lateral radiographs in both flexion and extension; the distance between the distal patella and avulsed fragment will increase during flexion 4

Fracture Classification and Treatment Algorithm

Ogden Classification System

The classification determines treatment approach 1, 2:

• Type I: Avulsion of distal ossification center

  • Type IA (non-displaced): Cast immobilization acceptable
  • Type IB (displaced/comminuted): ORIF required 1

• Type II: Upward angulation of fragment at secondary ossification center junction

  • Type IIA (non-displaced): Cast immobilization acceptable
  • Type IIB (displaced): ORIF required 1

• Type III: Fracture extends into knee joint (intra-articular)

  • Type IIIA and IIIB: Closed reduction and internal fixation (CRIF) should be attempted first 1
  • If CRIF fails to achieve anatomic reduction under fluoroscopy, proceed to ORIF 1

Surgical Technique Selection

For displaced extra-articular fractures (Types IB, IIA):

• ORIF is necessary using interfragmental transphyseal screws 4, 2
• At age 12, the proximal tibial physis is approaching closure, making transphyseal screw fixation safe 4

For intra-articular fractures (Types IIIA, IIIB):

• Attempt CRIF first under fluoroscopic guidance 1
• Anatomic reduction of the articular surface is the primary goal 2
• If adequate reduction cannot be achieved closed, proceed immediately to ORIF 1
• Consider tension band wiring if extensive comminution is present 4

For patellar ligament avulsion (Type C):

• ORIF with trans-osseous suture repair of the ligament 4
• Protect the ligament repair with tension band passed above patella and distally into tibia 4
• Remove protective tension band at 6 weeks 4

Critical Technical Points

• Achieve anatomic reduction when the fracture extends into the joint surface to prevent post-traumatic arthritis 2
• Use fluoroscopy intraoperatively to confirm reduction quality and hardware position 1
• If the avulsed fragment is too small or comminuted for screw fixation, use suture bridge technique or tension band wiring 5, 4

Postoperative Rehabilitation

• Begin protected range of motion between 0-60 degrees within the first week if tension band protection is used 4
• Remove protective tension band at 6 weeks to allow full rehabilitation 4
• Weight-bearing progression depends on fracture stability and fixation method 1

Common Pitfalls to Avoid

• Do not treat displaced fractures conservatively—this leads to extensor lag and chronic disability 4, 2
• Do not miss associated patellar ligament avulsion in Type I and II fractures; always test active extension 4
• Do not accept non-anatomic reduction in intra-articular fractures (Type III)—this causes long-term joint dysfunction 2
• Be aware that pre-existing Osgood-Schlatter disease may predispose to this injury and affect bone quality 6

Expected Outcomes

• With accurate reduction and sound fixation, uncomplicated union without deformity occurs in the vast majority of cases 2
• All patients should achieve full function with appropriate surgical management 1, 2
• Growth disturbance is rare at this age given proximity to physeal closure 4