Tibial Tubercle Avulsion Treatment & Management

Updated: May 27, 2020
  • Author: Janos P Ertl, MD; Chief Editor: Thomas M DeBerardino, MD  more...
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Approach Considerations

Type I fractures are minimally displaced. Even though such fractures may not be displaced, it is difficult to maintain this reduction against the pull of the quadriceps muscle. Type I fractures generally can be treated with cast immobilization. However, close observation in the first 2 weeks is necessary. Often, percutaneous or open reduction can be performed to maintain motion within the knee.

Type II lesions maintain an intact superior contact between the avulsed portion of the tibial tubercle and the remaining portion of the tibial epiphysis. The articular surface of the knee is not disrupted. In type III injuries, the fracture extends through the articular surface of the knee with occasional meniscal disruption.

Type II and III injuries require stabilization of the extensor mechanism through an open technique to replace the fragment and to remove any interposed periosteum. Displaced types II and III avulsion fractures require operative fixation because of loss of the extensor mechanism length, tension, and continuity. [12, 13, 14]  In type III injuries, exploration of the knee joint is necessary to address intra-articular comminution and possible meniscal pathology that may necessitate meniscal  repair.


Surgical Therapy

For all fracture types, ice therapy, splint immobilization, and elevation should be initiated to avoid significant swelling. [15, 16, 17, 18]

Types IB, II, and III tibial tubercle fractures require open reduction with internal fixation (ORIF). An anterior approach to the knee is followed over the proximal tibia. Fixation is best accomplished with one or two screws through the tibial tubercle into the proximal tibia. C-arm control is recommended to avoid overpenetration of the posterior tibial cortex.

Growth arrest is uncommon, in that this fracture usually occurs at the end of physeal closure. Should significant growth remain, smooth Kirschner wires (K-wires) may be used temporarily to allow continued growth and avoid the possibility of recurvatum (hyperextension). In younger patients, the periosteum and retinaculum may be sutured. The screws should be placed at a right angle to the avulsed fragment, proximally and posteriorly, not inclined distally, to avoid a tendency to pull out.

In type III fractures, comminution and meniscal disruption may be present. An anterior medial arthrotomy is recommended for visualization and exploration. Anatomic reduction should be the goal. Temporary fixation with K-wires may be applied and radiographically evaluated before definitive fixation. Meniscal tears should be repaired, and tibial plateau articular continuity should be reestablished. (See the image below.)

Intraoperative view after open reduction and inter Intraoperative view after open reduction and internal fixation of a type III tibial tubercle avulsion.

An advanced approach to evaluation and treatment is arthroscopic-assisted reduction and internal fixation. The tibial plateau can be visualized, fragments repositioned, and meniscal pathology addressed. Cross-training in both arthroscopic techniques and fracture treatment is necessary.

Should a compartment syndrome be identified, preparation is made for release of all the affected compartments. Because of the large vascular bone surface involved, this may be found in type III patterns.

A study of 12 children with acute tibial tubercle avulsion was undertaken by Pesl and Havranek to determine optimal treatment for various types of the injury. [12] They found that in patients with displaced extra-articular injury (types IB and IIA), ORIF was required. Closed reduction and internal fixation was found to be sufficient in intra-articular fractures (types IIIA and IIIB), except for one case.

Abalo et al found that closed reduction and cast immobilization were acceptable therapy for minimally displaced tibial tubercle fractures and that ORIF was favored for displaced fractures. [13]

Zrig et al treated nondisplaced tibial tubercle fractures conservatively, with immobilization for 6 weeks, and displaced fractures with internal fixation with plaster for 6 weeks and noted satisfactory results in all cases, consisting of functional recovery, resumption of sports activities to previous levels, and an absence of recurvatum. [14]

A small study by Checa Betegón et al (N = 10) suggested that some pediatric tibial tubercle avulsion fractures generally regarded as requiring surgery may be manageable by nonsurgical means. [19]  Of the 11 acute avulsions (one type I, three type II, four type III, and three IV), five were treated conservatively (including all three type IV), and only six were treated surgically. Results were satisfactory in all cases, with a 100% percentage of sport reincorporation in less than 25 weeks. The only reported complication, intolerance of material, did not require additional surgery.

A study comparing the outcomes of unicortical and bicortical fixation in pediatric tibial tubercle avulsion fractures found no significant differences, with all patients showing full healing and return to activities with very low complication rates. [20]  These results suggested that unicortical fixation suffices for these fractures.

Procedural details

Surgical preparation should include a preoperative planning for the following:

  • Anterior surgical approach
  • Removal of interposed soft tissue (periosteum)
  • Evaluation for intra-articular extension, comminution, or meniscal tear, usually type III injuries
  • Reduction of fragment with bone reduction forceps
  • Evaluation of reduction under fluoroscopic control
  • Placement of one or two interfragmentary compression screws; possible washers, cannulated or noncannulated
  • Evaluation of fixation with fluoroscopy
  • Repair of periosteum
  • Evaluation of fixation stability
  • Wound closure
  • Placement of range-of-motion (ROM) brace

In all open reductions, check for interposed periosteum, remove from the fracture site, and maintain the periosteal attachment for later repair. In type III fractures, a medial peripatellar arthrotomy may be necessary to evaluate the articular surface for comminution, as well as for possible meniscal tear.


Postoperative Care

If the fixation is believed to be stable, ROM therapy is initiated. Consultation with a physical therapist (PT) is requested for crutch-assisted touchdown weightbearing (TDWB) ambulation. Heel sliding under PT assistance or continuous passive motion (CPM) is initiated.

CPM is started from 0º to 45° at 2 cycles/min. It is then increased incrementally over a 1- to 2-week period or as the patient tolerates. TDWB is continued for a minimum of 5-6 weeks, at which time progressive full weightbearing may be resumed. Lower-extremity strengthening and hamstring stretching exercises also are started at this time.



Complications of treatment of tibial tubercle avulsion fracture include genu recurvatum (hyperextension) due to premature physeal closure of the anterior physis. However, this complication is rare because the fracture usually occurs in the transitional physis, near the end of closure and growth.

Residual knee stiffness may occur secondary to prolonged immobilization and arthrofibrosis.

Patella alta may occur if the reduction is not anatomic or if fixation is not stable enough, leading to proximal migration of the tubercle fragment. [21, 22]

An episode of a type III injury in an athlete that led to compartment syndrome is described: The patient was playing basketball and sustained an acute type III injury. The patient was seen in an emergency department, placed on crutches, and told to follow up at his home of record. No immobilization was given. The patient was placed on a commercial airplane with his leg maintained in a dependent position. Upon arrival, the patient exhibited a full-blown compartment syndrome, necessitating a four-compartment fasciotomy. Arthroscopy and internal fixation of the fracture were performed.


Long-Term Monitoring

The patient is discharged from the hospital when pain is manageable on an outpatient basis. Follow-up evaluations are performed at 10-14 days, 4 weeks, 2 months, 3 months, and 6 months, with anteroposterior (AP) and lateral radiographs obtained until the fracture has healed. Additional visits may be required, depending on patient progress. The brace is removed after 5-6 weeks. Physical therapy is continued on an outpatient basis as outlined above.