Tibial Eminence Fracture
synonyms: tibial eminence avulsion, tibial spine facture, tibial spine avulsion, ACL avulsion
Tibial Eminence Fracture ICD-9
Tibial Eminence Fracture Etiology / Epidemiology / Natural History
- generally occur between age 8-14
- most often result from a fall from a bicycle
- equivalent to rupture of the ACL in adults
Tibial Eminence Fracture Anatomy
- tibial intercondylar eminence is insertion site of ACL. Fracture represents avulsion of the ACL. The chondroepiphyseal insertion site is weaker than the ACL until maturation making emminence fracture more common than midsubstance ACL tears in adolescence.
- The anterior horn of the lateral meniscus is usually also attached to the avulsed intercondylar eminence (Lowe J. JBJS 2002;84A:1933-38)
Tibial Eminence Fracture Clinical Evaluation
- Painful knee, difficulty weight bearing
- Moderate to large effusion
- Lachman: generally have postive Lachman although pain usually prevents testing.
- Complete NV exam required.
Tibial Eminence Fracture Xray / Diagnositc Tests
- A/P, Lateral and oblique xrays: tibial eminence avulaion usually best seen on lateral view.
- CT: generally not needed, but can better define fractrue pattern
- MRI: generally not needed, but allows identification of associated meniscal, ligamentous and chondral injuries
Tibial Eminence Fracture Classification / Treatment
- Classification: Meyers MH, McKeever FM, JBJS 52A:1677 1970
- Type I =the fragment is minimally displaced from its bed in the tibia: only slight elevation of the anterior margin. RX=aspiration of hemartrosis for comfort, long leg cast flexed at 20° for 6-12wks
- Type II =the anterior third to half of the avulsed fragment is elevated from its bone bed, producing a beak-like appearance in the lateral radiograph. RX=aspirate hemartrosis for comfort, attempt CR (may need to be done in OR). If reduced place in long leg cast in reduced postion (usually extension to 20 degrees of flexion for 6-12wks. Consider ARIF (arthroscopic reduction internal fixation) if fails to reduce.
- Type III =the avulsed fragment is completely lifted from its osseous bed in the intercondylar eminence, and there is no bone apposition. RX=ARIF.
- Antegrade screw fixation provides stongest repair technique (Tsikada H, Arthroscopy 2005;21:1197).
Tibial Eminence Technique (ARIF)
- Attempted closed reduction in OR with patient sedated. Reduction may be blocked by anterior horn of medial meniscus or the anterior horn of the lateral meniscus may be attached to the fragment preventing reduction
- Standard knee arthroscopy
- Be cautious of compartment syndrome due to capsular disruption and fluid extravasation
- 2-cm vertical incision medial to tibial tuberosity
- Using ACL guide drill 2 2.4mm tunnels on medial and lateral sides of avulsed tibial fragment. Preserve at least 1cm bone bridge on anterior tibia. The Risk of growth disturbance with transepiphyseal drilling has not been established. If possible avoid crossing the physis.
- Place suture passer through medial drill hole into the knee joint.
- Using a suture passer/retriever place a loop of #2 non-absorbable suture(Ethibond) through the suture passer loop and across the substance of the ACL
- Grasp loop on lateral side of ACL and pull through lateral bone tunnel.
- Cut loop. Two strands of suture have now been placed through the ACL. The Fracture is reduced and the sutures are tied.
- Irrigate incision
- Close wound in layers
- Technique description: Hsu SYC, Arthroscopy 2004;20:96-100, Lubowitz JH, Arthroscopy 2005;21:86).
- Alternatives: cannulated screw fixation (Hunter RE. Arthroscopy 2004;20:113-121), screws generally require hardware removal and must not cross the physis.
Tibial Eminence Fracture Associated Injuries / Differential Diagnosis
- meniscal tear
- ACL/PCL tear
- capsular disruption
- chondral injury
- more complex tibial plateau fx
Tibial Eminence Fracture Complications
- Instability / residual laxity
- Posterior neurovascular injury
- Stiffness / limited ROM
- Knee Pain
- Loss of reduction
- Growth disturbance
Tibial Eminence Fracture Follow-up Care
- Weight-bearing as tolerated in hinged-knee brace locked in extention for 3 weeks.
- Begin ROM exercises to 90 degrees with physical therapy at 1 week.
- Hinge opened from 0-90 degrees at 3 weeks.
- Generally discontinue brace at 6 weeks.
- Patients often have persistent laxity to stress testing, but excellent functional outcomes (Kocher MS. Arthroscopy 2003;19:1085-1090)
Tibial Eminence Fracture Review References
- Lubowits JH, Elson WS, Guttmann D. Part II: Arthroscopic Treatment of Tibial Plateau Fractures: Intercondylar Eminence Avulsion Fractures. Arthroscopy 2005;21:96-92.
- Stanitski CL, JAAOS 1995;3:146-158
- Willis R, JPO 1993;13:361