- one of most common knee injuries in children;
- most common in children between ages of 8-14 yrs;
- usually result from avulsions of anterior intercondylar eminence from pull of ACL;
- fragment of tibial spine may be non displaced, or displaced;
- even w/ complete frx, partial ACL injury may occur w/ this injury;
- frx of posterior intercondylar eminence are rare and usually occur in skeletally mature patients.
- disruption of PCL can also be found in this injury;
- commonly caused by fall from bicycle or motorcycle;
- caused by forceful hyperextension of knee or by a direct blow on distal end of femur w/ the knee flexed;
- excessive tension on ACL, which inserts into anterior tibial spine, results in an inter-articular fracture;
- anterior, posterior, or both tibial spines may be fractured;
- frx of intercondylar eminence are classified by deg of displacement;
- type I:
- non-displaced & only anterior edge of eminence is sl elevated;
- has a posterior hinge with an elevated anterior portion;
- type II
- partially displaced frx, w/ anterior elevation of the eminence;
- type III A
- entire eminence lies above its bed, out of contact w/ tibia;
- this injury type usually occurs in children older than age 10-11 years;
- type III B
- the eminence is rotated as well as out of contact;
- type III frx are most common, accounting for 83 (45 %) of frx;
- Natural history of a type III fracture of the intercondylar eminence of the tibia in an adult. A case report.
- Physical Findings
- pts have pain & hemarthrosis & are reluctant to bear wt on affected extremity;
- extremes of motion cause tenderness;
- look for associated w/ tear of medial or lateral collateral ligament;
- PCL tear is dx'ed w/ posterior sag sign, posterior drawer, and quadriceps active test;
- Radiographic Evaluation
- lateral radiograph:
- avulsed frag may be composed of non-ossified cartilage & may be difficult to recognize;
- stress radiographs:
- should be made w/ pt sedated or under GEA.
- indicated w/ suspected tear of collateral ligament or physeal injury;
- look for abnormal widening of joint space;
- full extension of knee joint tends to reduce the fragment & hold it in position during healing;
- block to full knee extension:
- block to full extension may be caused by interposition of the anterior horns of either the medial (most often) or lateral meniscus (rare);
- attempt trial of closed reduction under anesthesia;
- if full extension is not obtained, reduction is probably not complete;
- w/ failed closed reduction in extension, consider arthroscopic assisted reduction or open reduction;
- fragment may be prevented from reduction by interposed lateral meniscus;
- type III b fractues should be treated by open reduction;
- Entrapment of the medial meniscus in a fracture of the tibial eminence.
- Incarceration of the meniscus in fractures of the intercondylar eminence of the tibia in children.
- The Anatomy of Tibial Eminence Fractures: Arthroscopic Observations Following Failed Closed Reduction.
- Tibial eminence fractures in children: prevalence of meniscal entrapment.
- Non Operative Treatment:
- nondisplaced or minimally displaced frx:
- some recommend immobilization of knee in full extension in long leg cast;
- some recommend immobilization w/ knee in 20 deg of flexion since ACL is most relaxed in this position;
- immobilize for four to six weeks;
- ref: Nonoperative treatment of tibial spine fractures in children-38 patients with a minimum follow-up of 1 year.
- Operative Treatment:
- indicated for displaced fractures;
- procedure is carried out under arthroscopic visualization;
- use the ACL tibial guide to effect the reduction of the intercondylar eminence fracture;
- a small incision is made just medial to the tibial tubercle;
- two guide pins are inserted on either side of the ACL thru the intercondylar fragment;
- sequentially pull the guidewires and in their place, insert a cannulated suture passer in their place;
- as each suture passer enters the joint, an arm of a No 5 ethibond suture (or fiberwire) is placed into the mouth of the suture passer,
and is then drawn out of the joint;
- tension on the sutures will firmly reduce the intercondylar eminence frx;
- the sutures are then tied over a bony bridge;
- alternatively consider arthroscopically guided screw placement that does not cross the proximal tibial physis;
- need to tension the reduction (over reduction)
- intersubstance stretching of ACL occurs in associationwith the tibial spine fracture and therefore, overreduction
may be considered;
- excessive ACL tightening is not associated with poor outcomes;
- well-reduced tibial eminence fractures showsubtle increases in anteroposterior knee laxity, albeit without functional deficit;
- The Role of Arthroscopic Surgery in the Treatment of Fractures of the Intercondylar Eminence of the Tibia.
- Open Versus Arthroscopic Reduction for Tibial Eminence Fracture Fixation in Children
- may be due to stretching of the ligament at the time of injury
- laxity is rarely severe enough to limit activities or requires treatment;
- children < ten years old are less likely to have symptomatic laxity;
- Knee instability after fracture of the intercondylar eminence of the tibia.
- Clinical and radiological results of arthroscopically treated tibial spine fractures in childhood.
- Laxity and functional outcome after arthroscopic reduction and internal fixation of displaced tibial spine fractures in children.
- may cause flexion deformity of knee
The Role of Arthroscopic Surgery in the Treatment of Fractures of the Intercondylar Eminence of the Tibia.
Incarceration of the meniscus in fractures of the intercondylar eminence of the tibia in children.
Fracture of the tibial spine in adults and children. A review of 31 cases.
Comminuted tibial eminence anterior cruciate ligament avulsion fractures: failure of arthroscopic treatment.
Arthroscopic Treatment of Fractures of the Tibial Spine.
Fracture of the intercondylar eminence of the tibia: a review of 35 patients.
Fractures of the tibial spine in children. An evaluation of knee stability.
Arthroscopic fixation of avulsion fractures of the tibial eminence: technique and outcome.
Biomechanical Comparison of Four Different Fixation Techniques for Pediatric Tibial Eminence Avulsion Fractures