Secondary Logo

Journal Logo

Pediatric ACL Tears

Natural History

Dingel, Aleksei BS*; Aoyama, Julien BS; Ganley, Ted MD; Shea, Kevin MD*

Journal of Pediatric Orthopaedics: July 2019 - Volume 39 - Issue - p S47–S49
doi: 10.1097/BPO.0000000000001367
Supplement Articles
Free

Background: Increased participation in youth sports is associated with increased rates of anterior cruciate ligament (ACL) tears in the skeletally immature. Historically, ACL reconstruction was avoided in the skeletally immature, or delayed until skeletal maturity, to avoid physeal injury and growth disturbance. Current practices and meta-analyses support early ACL reconstruction in some groups, to allow for return to activities and to avoid delayed cartilage/meniscus injury.

Purpose: The purpose of this article was to report on the natural history of ACL injuries in the skeletally immature.

Methods: A review of published literature on pediatric, skeletally immature ACL tears and conservative, nonoperative treatment was conducted via Pubmed articles published from 1970 to 2018. The search criteria included the key terms “anterior cruciate ligament,” “pediatric” and/or “adolescent,” and “conservative” and/or “nonoperative treatment.” A PRISMA workflow was used to narrow down the articles to those relevant to our analysis and available in full text format.

Results: Multiple articles on the nonoperative treatment of the ACL showed secondary meniscal and cartilage damage at the time of follow-up. Some articles showed no difference between the rates of secondary injuries between the surgical and nonsurgical treatment groups; however, the nonsurgical treatment groups were often on significant activity modification. Some articles concluded that nonoperative treatment of the ACL tear may be appropriate in low risk, lower level activity patients, and those that will comply with activity restrictions. Even with bracing and PT programs, active athletes treated without surgery appear to have a concerning rate of secondary meniscus injury after the primary ACL injury event.

Conclusions: The natural history of the ACL tear shows nonoperative treatment for the skeletally immature may be a viable treatment pathway for those who are able to comply with the physical activity restrictions. For the general population of young, active adolescents, an ACL injury treated nonoperatively often leads to secondary meniscal and/or cartilage damage, which may lead to knee degeneration and functional instability.

*Department of Orthopaedics, Stanford University, Stanford, CA

Children’s Hospital of Philadelphia, Philadelphia, PA

The authors declare no conflicts of interest.

Reprints: Kevin Shea, MD, Department of Orthopaedics, Stanford University, 300 Pasteur Drive, Edwards Bulding, Room R105, Stanford, CA 94305. E-mail: kgshea@stanford.edu.

Participation in youth sports, sports intensity, and early sports specialization has increased over the past 30 years. Year-round-training,1 longer practice sessions, and entering sports at a younger age2 are all common occurrences today. These factors have led to an increase in injuries in pediatric patients, particularly anterior cruciate ligament (ACL) tears in skeletally immature athletes.3,4 Numerous epidemiologic studies have demonstrated an increase in both tibial spine fractures and ACL tears in the pediatric population over the last 20 years.5–8 The purpose of this article was to report on the natural history of ACL injuries in the skeletally immature.

Back to Top | Article Outline

METHOD

A review of published literature on pediatric, skeletally immature ACL tears and “conservative,” nonoperative treatment was conducted via Pubmed articles published from 1970 to 2018. The search criteria included the key terms “anterior cruciate ligament,” “pediatric” and/or “adolescent,” and “conservative” and/or “nonoperative treatment.” A PRISMA workflow was used to narrow down the articles to those relevant to our analysis and available in full text format.

Back to Top | Article Outline

RESULTS

In 1988, McCarroll and colleagues conducted a prospective study of 40 skeletally immature patients with open physes undergoing either operative (24 patients) or nonoperative care (16 patients) for a mid-substance ACL rupture. After an average follow-up of 2.5 years, they found that only 7 of the 16 nonoperatively treated patients had returned to sports and all 16 reported recurrent episodes of giving way, effusions, and pain. Conversely, all of the 24 patients who underwent ACL reconstruction (10 I.T. band, 14 patellar tendon) returned to sport and 22 of the 24 were still competing at the 2.5 year follow-up. One of the 24 had reinjured the meniscus and another had reinjured the ACL. No patients from the surgical group sustained leg length discrepancy. McCarroll et al9 concluded that the athletic desires of the patient should be used as an indication as to whether operative or nonoperative treatment route is best for the patient.

In 1995, Mizuta and colleagues reported on 18 skeletally immature patients with ACL tears all treated nonoperatively. At the time of follow-up only 1 patient had returned to the same level of preinjury athletics, and the overall functional scores were fair to poor in 16/18 patients. They concluded that the results of nonoperative treatment yielded poor, unacceptable results.10

In 2013, Moksnes and colleagues reported on a study of 40 patients 11.0±1.4 years of age with ACL injuries (80.5% nonoperative treated knees and 19.5% surgically treated). At the 3.8±1.4 year follow-up, only 28.5% of the 28 nonoperatively treated knees showed an increase in meniscal injury, as found in the follow-up magnetic resonance imaging. Only 3.6% of the nonoperative knees were found to have obtained new meniscal and cartilage injuries. They report the majority (88%) of the patients were physically active at the 3.8±1.4 year follow-up.11

Conversely, Vavken and Murray conducted a systematic review in 2011 on conservative versus operative treatment of ACL tears in the skeletally immature patient culminating in a review of 12 conservative treatment articles. They reviewed a total of 476 patients with an average follow-up time of 52.7±11.9 months and report multiple accounts of knee instability and meniscal and cartilage damage eventually requiring surgical intervention.12 One study reviewed found no increase in secondary injury rates between the operative and nonoperative treatment groups. These authors maintain that “absolute activity restriction is key” to avoiding further injury.13 Vavken and Murray conclude that conservative treatment should be reserved for compliant patients who have a low physical activity levels.

Because of concerns about physeal injury, some centers have implemented protocols to delay ACL surgical reconstruction until skeletally maturity. Moksnes et al14 demonstrated that use of ACL brace and rehab may allow the majority of skeletally immature to return to activities with a brace, with up to 65% returning to sports before ACL reconstruction after maturity. About 10% sustained secondary meniscus injury. Additional research by Moksnes et al15 showed immature athletes returned to activity, but at reduced levels in up to 38%. In 2014, Moksnes and colleagues reported on a prospective case series of 41 skeletally immature ACL injuries treated with nonoperative care. After an average follow-up at 3.8 years postinjury, 88% of the patients were participating in pivoting sports suggesting nonoperative treatment may be a viable option for some patients. However, 19.5% of the patients had sustained new meniscal injuries.11 Moksnes et al16 suggested that nonoperative treatment could be an option for the skeletally immature patients who do not present with major instability, and could allow the patient to postpone surgery until they have reached skeletal maturity. The main downside to this approach appears to be a significant risk of secondary meniscus injury for active children who delay ACL reconstruction.

Back to Top | Article Outline

DISCUSSION

This review shows that nonoperative treatment protocols may be considered reasonable for pediatric ACL ruptures for those patients who can comply with significant or complete activity restriction.17,18 For active patients, conservative treatment has been shown to result in secondary meniscal and cartilage injury and premature degeneration, even in the setting in which rehab training and brace wear are part of the treatment protocols.9,10,12,14,15,19–25 Recurrent episodes of knee instability are common for those who attempt to resume high level athletics without a reconstruction. Some surgeons chose a nonoperative treatment route such as physical therapy, bracing, and activity modification until the patient is skeletally mature. Physical therapy focused on muscle strengthening combined with bracing may improve the functional outcomes of those ACL deficient knee, but nonoperative measures were not often effective unless coupled with significant activity restriction.11,13,26

Back to Top | Article Outline

CONCLUSIONS

The ACL is a vital knee ligament providing stability and preventing secondary knee injury in active individuals. Knee instability, further meniscal/chondral damage, and an inability to resume sporting activity have been reported as consequences of delayed surgical treatment after ACL injury in young patients. For these reasons, surgical procedures may be recommended in active patients to restore functional knee stability, and to reduce the risk of secondary injury.

Back to Top | Article Outline

REFERENCES

1. Gornitzky AL, Lott A, Yellin JL, et al. Sport-specific yearly risk and incidence of anterior cruciate ligament tears in high school athletes: a systematic review and meta-analysis. Am J Sports Med. 2016;44:2716–2723.
2. Jayanthi NA, LaBella CR, Fischer D, et al. Sports-specialized intensive training and the risk of injury in young athletes: a clinical case-control study. Am J Sports Med. 2015;43:794–801.
3. Dodwell ER, Lamont LE, Green DW, et al. 20 years of pediatric anterior cruciate ligament reconstruction in New York State. Am J Sports Med. 2014;42:675–680.
4. Shea KG, Grimm NL, Ewing CK, et al. Youth sports anterior cruciate ligament and knee injury epidemiology: who is getting injured? In what sports? When? Clin Sports Med. 2011;30:691–706.
5. Cruz AI Jr, Richmond CG, Tompkins MA, et al. What’s new in pediatric sports conditions of the knee? J Pediatr Orthop. 2018;38:e66–e72.
6. Mayo MH, Mitchell JJ, Axibal DP, et al. Anterior cruciate ligament injury at the time of anterior tibial spine fracture in young patients: an observational cohort study. J Pediatr Orthop. 2017. [Epub ahead of print].
7. Mitchell JJ, Sjostrom R, Mansour AA, et al. Incidence of meniscal injury and chondral pathology in anterior tibial spine fractures of children. J Pediatr Orthop. 2015;35:130–135.
8. Schneider F, Sperl M, Steinwender G, et al. Pediatric knee injuries. Orthopade. 2014;43:393–401; quiz 2–3.
9. McCarroll JR, Rettig AC, Shelbourne KD. Anterior cruciate ligament injuries in the young athlete with open physes. Am J Sports Med. 1988;16:44–47.
10. Mizuta H, Kubota K, Shiraishi M, et al. The conservative treatment of complete tears of the anterior cruciate ligament in skeletally immature patients. J Bone Joint Surg Br. 1995;77:890–894.
11. Moksnes H, Engebretsen L, Risberg MA. Prevalence and incidence of new meniscus and cartilage injuries after a nonoperative treatment algorithm for ACL tears in skeletally immature children: a prospective MRI study. Am J Sports Med. 2013;41:1771–1779.
12. Vavken P, Murray MM. Treating anterior cruciate ligament tears in skeletally immature patients. Arthroscopy. 2011;27:704–716.
13. Woods GW, O’Connor DP. Delayed anterior cruciate ligament reconstruction in adolescents with open physes. Am J Sports Med. 2004;32:201–210.
14. Moksnes H, Engebretsen L, Risberg MA. Performance-based functional outcome for children 12 years or younger following anterior cruciate ligament injury: a two to nine-year follow-up study. Knee Surg Sports Traumatol Arthrosc. 2008;16:214–223.
15. Moksnes H, Engebretsen L, Eitzen I, et al. Functional outcomes following a non-operative treatment algorithm for anterior cruciate ligament injuries in skeletally immature children 12 years and younger. A prospective cohort with 2 years follow-up. Br J Sports Med. 2013;47:488–494.
16. Funahashi KM, Moksnes H, Maletis GB, et al. Anterior cruciate ligament injuries in adolescents with open physis: effect of recurrent injury and surgical delay on meniscal and cartilage injuries. Am J Sports Med. 2014;42:1068–1073.
17. Hawkins RJ, Misamore GW, Merritt TR. Followup of the acute nonoperated isolated anterior cruciate ligament tear. Am J Sports Med. 1986;14:205–210.
18. Pattee GA, Fox JM, Del Pizzo W, et al. Four to ten year followup of unreconstructed anterior cruciate ligament tears. Am J Sports Med. 1989;17:430–435.
19. Lawrence JT, Argawal N, Ganley TJ. Degeneration of the knee joint in skeletally immature patients with a diagnosis of an anterior cruciate ligament tear: is there harm in delay of treatment? Am J Sports Med. 2011;39:2582–2587.
20. Henry J, Chotel F, Chouteau J, et al. Rupture of the anterior cruciate ligament in children: early reconstruction with open physes or delayed reconstruction to skeletal maturity? Knee Surg Sports Traumatol Arthrosc. 2009;17:748–755.
21. Millett PJ, Willis AA, Warren RF. Associated injuries in pediatric and adolescent anterior cruciate ligament tears: does a delay in treatment increase the risk of meniscal tear? Arthroscopy. 2002;18:955–959.
22. Newman JT, Carry PM, Terhune EB, et al. Factors predictive of concomitant injuries among children and adolescents undergoing anterior cruciate ligament surgery. Am J Sports Med. 2015;43:282–288.
23. Dumont GD, Hogue GD, Padalecki JR, et al. Meniscal and chondral injuries associated with pediatric anterior cruciate ligament tears: relationship of treatment time and patient-specific factors. Am J Sports Med. 2012;40:2128–2133.
24. Ramski DE, Kanj WW, Franklin CC, et al. Anterior cruciate ligament tears in children and adolescents: a meta-analysis of nonoperative versus operative treatment. Am J Sports Med. 2014;42:2769–2776.
25. Fabricant PD, Kocher MS. Anterior cruciate ligament injuries in children and adolescents. Orthop Clin North Am. 2016;47:777–788.
26. Nottage WM, Matsuura PA. Management of complete traumatic anterior cruciate ligament tears in the skeletally immature patient: current concepts and review of the literature. Arthroscopy. 1994;10:569–573.
Keywords:

anterior cruciate ligament; skeletally immature; natural treatment; knee instability; osteoarthritis

Copyright © 2019 Wolters Kluwer Health, Inc. All rights reserved.