Knee Pathology in Young Adults After Pediatric Anterior Cruciate Ligament Injury: A Prospective Case Series of 47 Patients With a Mean 9.5-Year Follow-up

Abstract

Background: The rate of secondary knee injuries after pediatric anterior cruciate ligament (ACL) injury is uncertain, and previous studies are limited because of poor methodology. Purpose: To evaluate the incidence of new meniscal injuries since the initial diagnostic magnetic resonance imaging (MRI) of young adults who sustained a pediatric ACL injury. In addition, to evaluate meniscal and cartilage injuries in the index knee and contralateral knee injuries on MRI at final follow-up (9.5 years). Furthermore, to assess leg length and alignment based on long-leg radiographs. Study Design: Case series; Level of evidence, 4. Methods: Study population at final follow-up included 47 young adults who sustained a pediatric ACL injury before age 13 years. They were followed prospectively since the time of injury for a mean 9.5 years at final follow-up. Imaging included diagnostic MRI of the index knee and 3.0-T MRI of both knees at 1-, 2-, and 9.5-year follow-up, in addition to long-leg radiographs at final follow-up. Forty-three patients underwent active rehabilitation without ACL reconstruction initially; 4 were treated with initial ACL reconstruction. At final follow-up, 27 (57%) had undergone ACL reconstruction. Results: Fourteen patients had meniscal tears in the index knee at final follow-up (prevalence, 30%). The majority of these were in the same location as previously repaired tears (n = 9). Between diagnostic MRI and final follow-up, 16 patients had sustained new meniscal tears to a healthy meniscus (incidence, 34%). At final follow-up, meniscal injuries recorded at baseline or during follow-up were no longer visible and appeared healed in 17 patients (20 tears). MRI at final follow-up showed cartilage injuries in the index knee of 13 patients (28%) and contralateral injuries in 8 patients (meniscus, n = 2; cartilage, n = 5; subchondral fracture, n = 1). Two patients had a leg-length difference >15 mm, and 3 had side-to-side difference in knee alignment >5°. Conclusion: The incidence of new meniscal tears after pediatric ACL injury was 34% during a mean follow-up period of 9.5 years. At final follow-up, 27 patients (57%) had normal menisci, and none had developed knee osteoarthritis. Primary active rehabilitation, close follow-up, and delayed surgery if needed may be a viable and safe treatment option for some pediatric ACL injuries.

Evidence too weak to guide surgical treatment decisions for anterior cruciate ligament injury: a systematic review of the risk of new meniscal tears after anterior cruciate ligament injury

“…At least 4143 (35%) patients were women; sex was not reported in 10 studies. Six studies included only patients who were skeletally immature as defined by remaining growth based on hand X-rays (n=3),52 57 70 open growth plates at X-rays and Tanner staging (n=2)53 71 or open growth plates at MRI (n=1) 72. Twenty-seven studies included only skeletally mature patients and 27 studies included a mixed population of patients aged under and over 16 years and did not clarify skeletal maturity.…”

“…Conversely, there is no definitive evidence that other treatment strategies, such as non-operative treatment with optional delayed surgery, are superior to early surgery for reducing the risk of new meniscal tears. However, non-operative treatment with optional delayed surgery may be a reasonable alternative 14 24 72 88. An RCT can address some of the selection bias problems of non-randomised studies with regard to a question about treatment.…”

Remarkably high prevalence of overuse-related knee complaints and MRI abnormalities in youth competitive alpine skiers: a descriptive investigation in 108 athletes aged 13–15 years

“…It has been shown that meniscal tears often heal spontaneously in that age group. 38 The clinically most relevant complaints relate to the distal and proximal patellar tendon Patellar tendinopathy is relatively common in adolescent athletes. In the literature, prevalence magnitudes of 5.8% (n=760, average age 13 years) and 7% (n=134, age 14-18 years) were reported for different sports.…”

Do Pediatric Patients With Anterior Cruciate Ligament Tears Have a Higher Rate of Familial Anterior Cruciate Ligament Injury?

“…21 Given these costs and the multitude of complications after ACL rupture including meniscal and cartilaginous damage, recurrent instability, and osteoarthritis, identification of predictive variables to identify those most at risk of ACL tears remains paramount. 8 –10,18,28 Prior studies 5,12,29 have identified several extrinsic risk factors, including sport played, weather conditions, and landing patterns, that show some association with risk of ACL injury. Even more intrinsic risk factors have been identified, including sex, prior injury, ligamentous laxity, increased tibial slope, decreased notch width, and multiple genetic markers (ie, familial predisposition).…”