1. Anterior Cruciate Ligament Injuries in the Skeletally Immature Patient
John F. Meyers, M.D.
Michael R. Magoline, M.D.
Orthopaedic Research of Virginia

2. ACL Injuries in the Skeletally Immature Overview
Introduction
Diagnosis
Assessment of Skeletal Maturity
Tibial Eminence Fractures
Nonsurgical Management
Surgical Management

3. ACL Injuries in the Skeletally Immature Introduction
ACL injuries in young patients are being diagnosed with increasing frequency
Higher clinical suspicion of ACL tears
More modalities to diagnose ACL tears (MRI)
More preadolescents participating in sports

4. ACL Injuries in the Skeletally Immature Introduction
Poor prognosis associated with nonsurgical management of ACL injuries with respect to sports and long term sequelae
High incidence of repetitive instability episodes (leading to early DJD?), meniscal tears and inability to return to sports

5. ACL Injuries in the Skeletally Immature Introduction
However: Efficacy and risks of surgical management are not well documented
Growth Arrest
Early graft failure
Early arthrosis

6. ACL Injuries in the Skeletally Immature Diagnosis
Differential diagnosis of anterior knee instability in the young patient
Tibial eminence fractures
Periarticular fractures
Constitutional laxity
Congenital absence of the ACL

7. ACL Injuries in the Skeletally Immature Diagnosis
Hx/Physical Exam
History of acute injury
Acutely swollen knee (50% incidence of ACL injury)
Mechanism of injury
Examination of contralateral knee

8. ACL Injuries in the Skeletally Immature Diagnosis
MRI
High level of specificity and sensitivity
Detects other pathology (meniscal tears, osteochondral injuries, etc.)

9. ACL Injuries in the Skeletally Immature Assessment of Skeletal Maturity
Important in considering reconstructive options
Patients with significant growth remaining are at increased risk for deformity and leg length discrepancy with surgical procedures performed at or near the physis

10. ACL Injuries in the Skeletally Immature Assessment of Skeletal Maturity
Physiologic Age (menarche, Tanner stage, cessation of change in shoe size)

11. Classification of Sexual Maturity Stages in Girls
Pubic Hair
Preadolescent
Sparse, lightly pigmented, straight, medial border of labia
Darker, beginning to curl, increased amount
Course, curly, abundant, but amount less than adult
Adult femenine triangle, spread to medial surface of thighs
Breasts
Preadolescent
Breast Papilla elevated and small mound; areolar diameter increased
Breast areola enlarged, no contour seperation
Areola and papilla form secondary mound
Mature; nipple projects, areola part of general breast

12. Classification of Sexual Maturity Stages in Boys
Pubic hair
None
Scanty, long. Slightly pigmented
Darker, starts to curl, small amount
Resembles adult type, but less in quantity, course curly
Adult distribution, spread to medial surface of thighs
Penis/Testes
Preadolescent
Slightly enlarged/enlarged scrotum, pin texture altered
Longer/larger
Larger; glans and breadth increase in size; scrotum dark
Adult size

13. ACL Injuries in the Skeletally Immature Assessment of Skeletal Maturity
Chronologic Age
Bone Age (Risser sign, Wrist film)
Family Height
Plain films of the knee (wide open growth plates vs. fused growth plates)

14. ACL Injuries in the Skeletally Immature Tibial Eminence Fractures
Unique pediatric variant of ACL injury
Tibial spine offers less resistance to traction forces than the substance of the ACL
Bony insertion of the ACL on the intercondylar eminence is avulsed

15. ACL Injuries in the Skeletally Immature Tibial Eminence Fractures: Classification Meyers and McKeever)
Type I: Nondisplaced
Type II: Hinged fragment
Type III: Displaced fragment

16. ACL Injuries in the Skeletally Immature Tibial Eminence Fractures: Treatment
Nonoperative management for nondisplaced or reducible fragments (Types I and II)
Arthroscopic reduction and fixation for displaced and irreducible fragments (Type III)

17. ACL Injuries in the Skeletally Immature Nonsurgical Management
Risk of iatrogenic physeal damage with reconstructive surgery
Some authors advocate activity modification rehabilitation and bracing until patient reaches skeletal maturity

18. ACL Injuries in the Skeletally Immature Nonsurgical Management
However: uniformly poor results reported with conservative management in the active pediatric population
Subsequent meniscal tears, instability episodes, early arthrosis

19. ACL Injuries in the Skeletally Immature Surgical Management
Reconstructive techniques focused on avoiding the growth plate
Primary ACL repair (Poor results)
Extraarticular reconstructions (non-anatomic, poor results)

20. ACL Injuries in the Skeletally Immature Surgical Management
In considering ACL reconstruction in the skeletally immature patient, need to assess how much growth is remaining

21. ACL Injuries in the Skeletally Immature Surgical Management
Patients close to skeletal maturity
Little growth remaining
Safe to treat as adults and offer them a reconstruction with transphyseal drill holes and graft of choice (B-T-B, etc.)

22. ACL Injuries in the Skeletally Immature Surgical Management
Skeletally immature patients
Wide open growth plates/significant growth remaining
Alter reconstructive technique (graft choice, femoral tunnel) to minimize risk of physeal arrest/deformity

23. ACL Injuries in the Skeletally Immature Surgical Management
Skeletally immature patients
Smaller grafts (6-7 mm) to accommodate size of knee as well as to minimize assault to tibial physis
Soft tissue grafts to avoid placing a bone block across the physis
Over the top fixation on the femoral side to avoid drilling across the femoral physis

24. Hamstring ACL Reconstruction
Harvest

25. Hamstring ACL
Graft preparation

30. ACL Injuries in the Skeletally Immature Summary
ACL injuries are being diagnosed with increasing frequency in the younger population
Results of nonoperative management in patients with symptomatic anterior instability are poor
Assessment of skeletal maturity is key in choosing reconstructive technique