Pediatric anterior cruciate ligament reconstruction

Pediatric ACL Reconstruction in Children-An Evaluation of the Transphyseal Technique's Efficacy and Safety

INTRODUCTION

Injuries of the anterior cruciate ligament (ACL) are commonly found in the general population, both among adult and pediatric patients, and their incidence has been increasing in recent years. Most of the late literature agrees that surgical reconstruction of the ACL is effective in improving long-term outcomes in pediatric patients, while others in the past have pleaded for non-surgical management.

PURPOSE/HYPOTHESIS

Our study aims to verify if ACL reconstruction (ACLR) using transphyseal technique in skeletally immature patients will provide angular deviations or growth restrictions.

STUDY DESIGN

Retrospective cohort study; Level of evidence 4.

METHODS

We perfomed a retrospective study to verify if transphyseal ACLR in children with less than or equal to 2 years of remaining growth leads to either limb length discrepancies or axis deviations.

RESULTS

Most patients who were treated using transphyseal technique showed significant improvements in their functional scores. There were statistically significant differences in lateral distal femoral angles (LDFA) and medial proximal tibial angles (MPTA), with no clinical impact. There was no significant limb length discrepancy (LLD) during the 2-year follow-up.

CONCLUSIONS

Transphyseal ACLR is safe among children who have less than or equal to 2 years of remaining growth and brings no risk of axis deviations or limb length discrepancy.

Criteria Used to Determine Unrestricted Return to Activity After ACL Reconstruction in Pediatric and Adolescent Patients: A Systematic Review

Background

The rates of anterior cruciate ligament (ACL) graft failure or contralateral ACL rupture range from 17% to 30% in pediatric patients after ACL reconstruction (ACLR). A contributing factor to the high reinjury rate in this population may be the limited evidence regarding appropriate criteria for allowing unrestricted return to activity (RTA) postoperatively.

Purpose

To review the literature and identify the most commonly used criteria when determining unrestricted RTA after ACLR in pediatric patients.

Study Design

Systematic review; Level of evidence, 4.

Methods

A search was performed of the Medline/PubMed, Cochrane Central Register of Controlled Trials, Embase, CINAHL, and SPORTDiscus databases using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The authors identified studies that included pediatric patients (<19 years of age) and specified the criteria used to determine RTA after ACLR.

Results

A total of 27 articles met all criteria for review, of which 13 studies only used 1 criterion when determining RTA. Objective criteria were the most common type of criteria for RTA (17 studies). Strength tests (15 studies) and hop tests (10 studies) were the most commonly used tasks when deriving RTA criteria. Only 2 studies used validated questionnaires to assess the patient's physiological readiness for RTA, and only 2 studies used an objective assessment of movement quality before RTA.

Conclusion

Only 14 of the 27 reviewed studies reported using >1 criterion when determining RTA. Furthermore, few studies used patient-reported outcome measures or lower limb kinematics as RTA criteria, indicating that more research is needed to validate these metrics in the pediatric population.

Distance to the Neurovascular Bundle for Iliotibial Band Graft Passage During Anterior Cruciate Ligament Reconstruction: A Pediatric Cadaveric Study

Background:

The Micheli technique for anterior cruciate ligament (ACL) reconstruction (ACLR) has proven to be a reliable method with a minimal risk for growth disturbance among skeletally immature patients.

Purposes:

To evaluate the Micheli technique of iliotibial band (ITB) graft passage for ACLR using cadaveric knee models and to measure the distance between the surgical instrument tip and the neurovascular bundle in the posterior knee joint: specifically, the peroneal nerve, tibial nerve, and popliteal artery.

Study Design:

Descriptive laboratory study.

Methods:

Gross dissection was performed on 17 pediatric cadaveric knees (12 male and 5 female) aged between 4 and 12 years. To simulate ITB graft passage, we passed a curved-tip hemostat clamp through the posterior capsule, with the knee flexed from 90° to 100°. Next, clinical photographs were taken, and digital imaging software was used to measure the distance in centimeters from the clamp tip to each respective neurovascular structure.

Results:

The mean distances from the clamp tip to the tibial nerve, popliteal artery, and peroneal nerve were 0.875 cm (range, 0.468-1.737 cm), 0.968 cm (range, 0.312-1.819 cm), and 1.149 cm (range, 0.202-2.409 cm), respectively. Mean values were further calculated for age groups of ≤8, 9-10, and 11-12 years. The mean distance from the clamp tip to the peroneal nerve was 1.400 cm larger for 11- to 12-year-old specimens than for ≤8-year-old specimens (95% CI, 0.6-2.2 cm; P = .005).

Conclusion:

The neurovascular structures in the posterior knee were in close proximity to the path of graft passage, with distances <1 cm in many specimens in this study. When passing the graft through the knee for an over-the-top position, surgeons should consider these small distances between the path of graft passage and critical neurovascular structures.

Clinical Relevance:

As the incidence of ACL tears is continuously increasing within the pediatric population, there are a larger number of ACLR procedures being performed. Although neurovascular injuries during ACLR are rare, this study clarifies the close proximity of neurovascular structures during ITB graft passage using the Micheli technique of ACLR.

Outcomes Following Primary Anterior Cruciate Ligament Reconstruction Using a Partial Transphyseal (Over-the-Top) Technique in Skeletally Immature Patients

BACKGROUND

The incidence of anterior cruciate ligament (ACL) injuries in skeletally immature patients is increasing, with ACL reconstruction preferred in this population due to reported chondroprotective benefits. Due to concerns with growth disturbance following ACL reconstruction in skeletally immature patients, various physealsparing and partial transphyseal techniques have been developed. Currently, there is no consensus on the most effective ACL reconstruction technique in skeletally immature patients. The purpose of the current study was to report the outcomes of a partial-transphyseal over-the-top (OTT) ACL reconstruction in a cohort of skeletally immature patients.

METHODS

All patients with radiographic evidence of open tibial and femoral physes that underwent primary ACL reconstruction using a partial-transphyseal OTT technique between 2009-2018 at a single tertiary-care institution with at least twelve months of clinical follow-up were retrospectively reviewed. Patient demographics, physical examination findings, graft ruptures, return to sport, and Tegner activity levels were analyzed. Statistical significance was defined as p<0.05.

RESULTS

Overall, 11 males and 1 female (12 knees) with a mean age of 12.8±1.8 (range: 10-16) years were included in the study. The mean postoperative follow-up of the cohort was 2.3±1.2 (range: 1.1-5.2) years. All ACLs were reconstructed with hamstring autograft with allograft augmentation utilized in a single patient. There were two cases of ACL graft rupture (16.7%). All patients were able to return to the same or higher level of sporting activity at an average of 7.4+2.7 months. There were no cases of clinically significant longitudinal or angular growth disturbance.

CONCLUSION

Partial transphyseal ACL reconstruction using a transphyseal tibial tunnel and an extra-articular OTT technique on the femur in skeletally immature patients affords minimal risk of growth disturbance with a graft rupture rate consistent with what has been reported in this high-risk population. All patients were able to return to sport at the same or higher level. Level of Evidence: IV.

Epidemiology and Revision Rates of Pediatric ACL Reconstruction in New York State

BACKGROUND

There are limited epidemiologic data examining the incidence of pediatric anterior cruciate ligament reconstruction (ACLR) over the past decade.

PURPOSE

To examine statewide population trends in the incidence of ACLR in a pediatric population.

STUDY DESIGN

Descriptive epidemiology study.

METHODS

Inpatient and outpatient claims for pediatric patients who underwent ACLR between 2009 and 2017 were identified in the New York Statewide Planning and Research Cooperative System database via International Classification of Diseases (ICD), Revision 9, Clinical Modification; ICD, Revision 10, Clinical Modification and Procedural Classification System; or Current Procedural Terminology codes. New York population data for each year between 2009 and 2017 were used from the New York State Department of Health to calculate the rates of ACLR per 100,000 people aged 3 to 19 years and determine the 95% confidence limits. The rates were then stratified by age, sex, and insurance. Two-year rates of revision and contralateral ACLR were also analyzed by sex.

RESULTS

Between 2009 and 2017, 20,170 pediatric ACLRs were identified. The rates of pediatric ACLR increased steadily from 49.3 per 100,000 in 2009 (95% CI, 47.2-51.4) to a peak of 61.0 (95% CI, 58.6-63.4) in 2014 and decreased to 51.8 (95% CI, 49.6-54.1) by 2017. The age group 15 to 17 years had the highest rates of ACLR of all age groups, peaking at 198.5 (95% CI, 188.3-208.7) per 100,000. Analysis by sex showed that ACLR rates between males and females were not different. Males had a 2-year ipsilateral revision rate of 4.3%, while females had a rate of 3.3% (P = .0001). Females had a contralateral ACLR rate of 4.0%, while males had a rate of 2.6% (P = .0002).

CONCLUSION

Pediatric ACLR rates continued to rise until 2014, but there was a demonstrable decrease in rates after 2014. This decline in pediatric ACLR may point to the efficacy of injury prevention programs or changes in practice management. The high revision rate in males and high contralateral surgery rate in females can help guide patient counseling for return to play and complication risk.

CLINICAL RELEVANCE

This study showed that ACLR in pediatric patients may be decreasing in recent years. There were differences in revision and contralateral ACLR by sex.

Wide Variability of Pediatric Knee Arthroscopy Case Volume in Orthopaedic Surgery Residency

Purpose

The purpose of this study was to evaluate orthopaedic surgery resident case volume and variability for adult and pediatric knee arthroscopy from 2016 to 2020.

Methods

The Accreditation Council for Graduate Medical Education surgical case log data from 2016 to 2020 for graduating United States orthopaedic surgery residents were analyzed. The average number of total (adult and pediatric), adult, and pediatric knee arthroscopy cases were compared from 2016 to 2020. The 10th and 90th percentiles of case volumes for adult and pediatric knee arthroscopy procedures were compared from 2016 to 2020 to determine caseload variability.

Results

There was an 18% increase in pediatric knee arthroscopy cases between 2016 and 2020 (average: 13.9 ± 10 to 16.4 ± 13; P < .005), a 5.4% decrease in adult knee arthroscopy cases (100 ± 45 to 94.6 ± 47; P < .027), and a 2.6% decrease in total knee arthroscopy (113.9 ± 47 to 111 ± 51; P = .264) cases. There was an 11-fold difference in the number of pediatric knee arthroscopy cases performed between the 10th and 90th percentile of residents in 2020 (3 vs 33 cases, respectively), a 3.28-fold difference for adult knee arthroscopy (47 vs 154, respectively), and a 2.98-fold difference for total knee arthroscopy (59 vs 176, respectively).

Conclusions

Pediatric knee arthroscopy comprises a small yet growing percentage of total knee arthroscopy case volume of graduating orthopaedic surgery residents. However, wide variability in resident exposure is present and likely masked by the abundance of adult cases performed each year.

Clinical Relevance

The findings presented in this study may assist in optimizing arthroscopy resident education. Existing ACL reconstruction and knee arthroscopy case minimum requirements could be updated to include a set number of pediatric cases. These changes might help reduce case volume variability and discrepancies in resident education.

Early Operative Versus Delayed Operative Versus Nonoperative Treatment of Pediatric and Adolescent Anterior Cruciate Ligament Injuries: A Systematic Review and Meta-analysis

BACKGROUND

Treatment options for pediatric and adolescent anterior cruciate ligament (ACL) injuries include early operative, delayed operative, and nonoperative management. Currently, there is a lack of consensus regarding the optimal treatment for these injuries.

PURPOSE/HYPOTHESIS

The purpose was to determine the optimal treatment strategy for ACL injuries in pediatric and adolescent patients. We hypothesized that (1) early ACL reconstruction results in fewer meniscal tears than delayed reconstruction but yields no difference in knee stability and (2) when compared with nonoperative management, any operative management results in fewer meniscal tears and cartilage injuries, greater knee stability, and higher return-to-sport rates.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 4.

METHODS

A systematic search of databases was performed including PubMed, Embase, and Cochrane Library using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Inclusion criteria were a pediatric and adolescent patient population (≤19 years old at surgery), the reporting of clinical outcomes after treatment of primary ACL injury, and original scientific research article. Exclusion criteria were revision ACL reconstruction, tibial spine avulsion fracture, case report or small case series (<5 patients), non-English language manuscripts, multiligamentous injuries, and nonclinical studies.

RESULTS

A total of 30 studies containing 50 cohorts and representing 1176 patients met our criteria. With respect to nonoperative treatment, knee instability was observed in 20% to 100%, and return to preinjury level of sports ranged from 6% to 50% at final follow-up. Regarding operative treatment, meta-analysis results favored early ACL reconstruction over delayed reconstruction (>12 weeks) for the presence of any meniscal tear (odds ratio, 0.23; P = .006) and irreparable meniscal tear (odds ratio, 0.31; P = .001). Comparison of any side-to-side differences in KT-1000 arthrometer testing did not favor early or delayed ACL reconstruction in either continuous mean differences (P = .413) or proportion with difference ≥3 mm (P = .181). Return to preinjury level of competition rates for early and delayed ACL reconstruction ranged from 57% to 100%.

CONCLUSION

Delaying ACL reconstruction in pediatric or adolescent patients for >12 weeks significantly increased the risk of meniscal injuries and irreparable meniscal tears; however, early and delayed operative treatment achieved satisfactory knee stability. Nonoperative management resulted in high rates of residual knee instability, increased risk of meniscal tears, and comparatively low rates of return to sports.

Measuring Proximal Tibial Metaphyseal Width and Lateral Epiphyseal Height Improves Determination of Remaining Growth in Children

BACKGROUND

Accurate assessments of skeletal maturity is of critical importance to guide type and timing of orthopaedic surgical interventions. Several quantitative markers of the proximal tibia were recently developed using historical knee radiographs. The purpose of the present study was to determine which marker would be most effective in assessment of full-length radiographs in a modern pediatric patient population.

METHODS

All full-length radiographs at our institutions between 2013 and 2018 were reviewed. Inclusion criteria for our study required that the child reached final height as defined by 2 consecutive unchanged heights, at least 6 months apart, after age 16 for boys and 14 for girls. Patients with metabolic bone disease, prior surgery such as epiphysiodesis, or previous infections around the knee were excluded. Summary statistics for each of the 3 proximal tibial ratios were calculated and multiple linear regression was performed with percent of growth remaining as a dependent variable. A recommended regression model is presented and evaluated.

RESULTS

A total of 692 full-length radiographs met inclusion criteria. Proximal tibial ratios were calculated and averaged values for each percent of growth remaining was presented. Multiple linear regression demonstrated that using all 3 variables led to overfitting of the model so tibial metaphyseal width/lateral tibial epiphyseal height was selected as the optimal ratio for use by clinicians. The optimal model for determining growth was found to have R2=0.723 in the developmental set and R2=0.762 in an excluded validation set.

CONCLUSIONS

This study demonstrates that the proximal tibial metaphyseal width/lateral tibial epiphyseal height is the ideal measurement for clinicians seeking to determine growth remaining in children. It presents average values between 0% and 25% of growth remaining. This study also develops and validates a multivariable regression model for determining percentage of growth remaining in children that will allow for quantitative determination of growth using full-length radiographs.

LEVEL OF EVIDENCE

Level III.

Trends of anterior cruciate ligament reconstruction in children and young adolescents in Italy show a constant increase in the last 15 years

PURPOSE

The aim of this 15-year nationwide study was to investigate the trend in ACL reconstructive surgeries in patients younger than 15 years old in Italy, as well as their social and economic impact.

MATERIALS AND METHODS

The National Hospital Discharge records (SDO) collected by the Italian Ministry of Health in the 15-year period between 2001 and 2015 were analyzed. This contains anonymous data including patients' age, gender, ICD-9-CM codes for diagnosis and intervention, census region, region of hospitalization, length of the hospitalization, and public or private reimbursement.

RESULTS

1,350 ACL reconstructions were performed in Italy in the population younger than 15 years old, with an incidence rate ranging from 0.16 to 2.04 procedures per 100,000 age-matched individuals. Similarly, the percentage of surgeries in 0-14 year old patients increased with respect to the total number of ACL reconstruction from 0.13% in 2001 to 0.95% in 2015. The age range 10-14 years is the most involved, accounting for 97.3% of surgeries recorded in the study period. The male:female ratio was 1.05 and most of these procedures were performed in the North of Italy (78.3%).

CONCLUSION

ACL reconstructions in patients aged 10-14 years are increasing constantly since 2001, and thus, specific actions aimed to define the best management strategy as well as national educational programs to prepare the future surgeons to this new reality are mandatory in the interest of the public health.

LEVEL OF EVIDENCE

Level III.

Modification of the Hybrid Anatomic Technique for Anterior Cruciate Ligament Reconstruction in Pediatric Patients

The incidence of anterior cruciate ligament (ACL) lesions with Tanner stage ≤4 has been increasing in children. To stabilize the knee, different surgical techniques have been developed for ACL reconstruction in the pediatric population. The use of a hybrid anatomic technique, intra-epiphyseal in the femur and transphysis in the tibia, has been recommended as the technique of choice to reconstruct the ACL in these patients. Despite the favorable results, this technique is not exempt from complications. The aim of this study was to present a simple and reproducible modification of the hybrid anatomic technique for ACL reconstruction in pediatric patients.

Bone age determination using only the index finger: a novel approach using a convolutional neural network compared with human radiologists

BACKGROUND

Recently developed convolutional neural network (CNN) models determine bone age more accurately than radiologists.

OBJECTIVE

The purpose of this study was to determine whether a CNN and radiologists can accurately predict bone age from radiographs using only the index finger rather than the whole hand.

MATERIALS AND METHODS

We used a public anonymized dataset provided by the Radiological Society of North America (RSNA) pediatric bone age challenge. The dataset contains 12,611 hand radiographs for training and 200 radiographs for testing. The index finger was cropped from these images to create a second dataset. Separate CNN models were trained using the whole-hand radiographs and the cropped second-digit dataset using the consensus ground truth provided by the RSNA bone age challenge. Bone age determination using both models was compared with ground truth as provided by the RSNA dataset. Separately, three pediatric radiologists determined bone age from the whole-hand and index-finger radiographs, and the consensus was compared to the ground truth and CNN-model-determined bone ages.

RESULTS

The mean absolute difference between the ground truth and CNN bone age for whole-hand and index-finger was similar (4.7 months vs. 5.1 months, P=0.14), and both values were significantly smaller than that for radiologist bone age determination from the single-finger radiographs (8.0 months, P<0.0001).

CONCLUSION

CNN-model-determined bone ages from index-finger radiographs are similar to whole-hand bone age interpreted by radiologists in the dataset, as well as a model trained on the whole-hand radiograph. In addition, the index-finger model performed better than the ground truth compared to subspecialty trained pediatric radiologists also using only the index finger to determine bone age. The radiologist interpreting bone age can use the second digit as a reliable starting point in their search pattern.

Understanding the undulating pattern of the distal femoral growth plate: Implications for surgical procedures involving the pediatric knee: A descriptive MRI study

INTRODUCTION

Operative procedures near the distal femoral physis can result in iatrogenic damage if one is not familiar with the complex anatomy of the growth plate. The purpose of this study was to use physeal-specific MRI sequences to delineate the anatomic dimensions of the distal femoral physis.

MATERIALS AND METHODS

Sixty patients underwent physeal-specific spoiled gradient 3-D fat saturated (SPGR) MRI analysis of a single knee. Three age groups (eight to 10, 11-13, and 14-16 years) comprised of equal numbers (n = 20) of boys and girls were evaluated. Using the SPGR coronal sequence, the distance of the physis to the femoral articular cartilage was recorded at the medial, mid-medial, notch, mid-lateral and lateral margins of the knee. Coronal measurements were recorded at four locations along the sagittal sequence, as the anteroposterior dimension of the knee was divided into equal quartiles.

RESULTS

While little variation in shape was observed in the anterior quartile, the remaining quartiles demonstrated significant variability that increased moving posteriorly (p < .001), therefore reflecting a more concave shape in the posterior aspect of the femur. These observations were statistically significant for age at the posterior two quartiles.

CONCLUSION

These MRI data suggest that while the physis is linear in the anterior part of the femur, it possesses a more concave shape in the posterior aspect of the medial and lateral condyles. Findings were preserved across gender and age. Ultimately, these data can aid in preoperative planning and should be considered when performing operative procedures in the skeletally immature knee.

The Pediatric Knee and Proximal Tibia

Pediatric knee disorders are various and range from trauma and sports injuries to chronic overuse injuries. Because pediatric patients are different from adults, management of pediatric injuries and general knee disorders is also often different. Primary treatment regimen goals focus on a return to the previous level of function, preservation of anatomy, and decreasing potential long-term effects. Long-term complications may include damage to the physis with resultant potential limb length discrepancy or deformity.

The incidence of paediatric ACL injury is increasing in Finland

PURPOSE

Anterior cruciate ligament (ACL) injury is a common knee injury in paediatric and adolescent patients. The population-based incidence of paediatric ACL injury is, however, unknown. Recent studies suggest increased ACL injury rates among adolescents, especially in active, sports-participating population. The purpose of this study was to investigate the population-based incidence rates of ACL injuries and trends in paediatric ACL reconstruction surgery.

METHOD

All ACL injuries were identified (ICD-10 diagnosis code S83.5) leading to hospitalisation or surgery using validated Finnish National Hospital Discharge Register (NHDR) data from 1997 to 2014. The sample comprised 19,961,205 Finnish residents aged less than 18 years at the time of injury. Hospital admissions with the diagnosis code S83.5 were analysed more thoroughly including, sex, age and the need for surgical interventions.

RESULTS

During the 18-year study period, 4725 subjects of the study population had sustained an ACL injury. The total ACL injury incidence in study population was 23.3 per 100,000 person-years. The median age of the patients at the time of injury was 16 years (range 4-17). The incidence of ACL injury increased with age, and the highest incidence was observed among 17-year old (113.5 per 100,000 person-years). Incidence rate did not differ between genders. From the total ACL injury population of 4725 hospitalisations, 3168 (67.0%) underwent ACL reconstruction, of which 2988 (94.3%) were treated with arthroscopic reconstruction and 180 (5.6%) with open surgery. In addition, 1557 (33.0%) were treated non-operatively without ACL reconstruction. The annual incidence of ACL injuries in the Finnish paediatric population has increased during the past 15 years. The lowest incidence rate was seen in 1999 (incidence of 17.7 per 100,000 person-years, 195 ACL injuries) and the highest in 2011 (incidence of 31.5 per 100,000 person-years, 346 ACL injuries). The highest increase in ACL injuries was seen in girls aged 13-15 years, with an increase of 143%.

CONCLUSION

ACL injury is not a negligible knee injury in the paediatric population. The incidence of paediatric ACL injury has increased during the past 15 years. Moreover, a twofold increase in incidence of paediatric ACL injury was noted during the last 10 years of the study period. Incidence rates among male and female paediatric patients were comparable.

LEVEL OF EVIDENCE

III.

Outcomes of Meniscus Repair in Children and Adolescents

PURPOSE OF REVIEW

The purpose of this study was to review the clinical and functional outcomes of meniscus repair in children and adolescents.

RECENT FINDINGS

The sequel of meniscal tears and the outcome of meniscus repair have been well studied in adults. However, these topics have received less attention in the pediatric population despite the high prevalence and potentially critical effect on long-term knee function in children. Meniscus repair has a healing rate ranging from 33 to 100% with less than 40% reoperation rate. Several factors have been suggested to play a role in healing, such as concomitant ACL reconstruction and complexity of the tear. There is a lack of standardization among the utilization of functional outcome and activity level questionnaires across studies; however, most report improved function postoperatively. Other important considerations include bucket handle tears, the discoid meniscus, rehabilitation and return to sports, and alternatives after failed meniscus repair. Based on the favorable outcomes reported, meniscus repair should be attempted in most meniscus tears in children.

Allograft or autograft in skeletally immature anterior cruciate ligament reconstruction: a prospective evaluation using both partial and complete transphyseal techniques

OBJECTIVE

We compared autografts and allograft using partial and complete transphyseal anterior cruciate ligament (ACL) reconstruction techniques among skeletally immature individuals.

METHODS

Male and females younger than 18 and 16 years old, respectively, diagnosed with ACL tear from April 2006 to March 2012 entered the study. One group had four-strand hamstring autograft, and the other had tibialis posterior allograft reconstruction. Those who had allografts either had hyper-laxity or recurvatum.

RESULTS

Achieved mean (± SD) 2000 International Knee Documentation Committee subjective score was not statistically different (P = 0.385) between allograft (n = 13) (84.3 ± 3.2) and autograft groups (n = 18) (85.6 ± 4.4). Mean Knee injury and Osteoarthritis Outcome Score (KOOS) subscale Knee-Related Quality of Life at 2 years was 78.0 ± 7.2 and 75 ± 7.4 for allograft and autograft groups, respectively (p = 0.261). Mean 2-year KOOS subscale Sports and Recreation was 82.1 ± 5.8 and 84.8 ± 6.6 for allograft and autograft groups, respectively (p = 0.244). No patient reported instability, giving way, or locking of the knee. Pivot shift test was negative in all patients; however, a minor positive Lachman test was found in six cases (46%) within the allograft group and seven cases (39%) in the autograft group. One postoperative septic arthritis was documented in the autograft group.

CONCLUSION

Considering existing concern that joint laxity and recurvatum are among the precursors of non-contact ACL injury in adolescents, bone-patellar-bone autografts are not applicable in this age group because of the open physis; furthermore, considering that hamstring autografts are insufficient (size thickness and stretchability), we recommend soft tissue allografts for ACL reconstruction in skeletally immature patients.

5-Year Survival of Pediatric Anterior Cruciate Ligament Reconstruction With Living Donor Hamstring Tendon Grafts

BACKGROUND

It is well accepted that there is a higher incidence of repeat anterior cruciate ligament (ACL) injuries in the pediatric population after ACL reconstruction (ACLR) with autograft tissue compared with adults. Hamstring autograft harvest may contribute to the risk for repeat ACL injuries in this high functional demand group. A novel method is the use of a living donor hamstring tendon (LDHT) graft from a parent; however, there is currently limited research on the outcomes of this technique, particularly beyond the short term.

PURPOSE/HYPOTHESIS

The purpose was to determine the medium-term survival of the ACL graft and the contralateral ACL (CACL) after primary ACLR with the use of an LDHT graft from a parent in those aged less than 18 years and to identify factors associated with subsequent ACL injuries. It was hypothesized that ACLR with the use of an LDHT provides acceptable midterm outcomes in pediatric patients.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Between 2005 and 2014, 247 (of 265 eligible) consecutive patients in a prospective database, having undergone primary ACLR with the use of an LDHT graft and aged less than 18 years, were included. Outcomes were assessed at a minimum of 2 years after surgery including data on ACL reinjuries, International Knee Documentation Committee (IKDC) scores, and current symptoms, as well as factors associated with the ACL reinjury risk were investigated.

RESULTS

Patients were reviewed at a mean of 4.5 years (range, 24-127 months [10.6 years]) after ACLR with an LDHT graft. Fifty-one patients (20.6%) sustained an ACL graft rupture, 28 patients (11.3%) sustained a CACL rupture, and 2 patients sustained both an ACL graft rupture and a CACL rupture (0.8%). Survival of the ACL graft was 89%, 82%, and 76% at 1, 2, and 5 years, respectively. Survival of the CACL was 99%, 94%, and 86% at 1, 2, and 5 years, respectively. Survival of the ACL graft was favorable in patients with Tanner stage 1-2 at the time of surgery versus those with Tanner stage 3-5 at 5 years (87% vs 69%, respectively; hazard ratio, 3.7; P = .01). The mean IKDC score was 91.7. A return to preinjury levels of activity was reported by 59.1%.

CONCLUSION

After ACLR with an LDHT graft from a parent in those aged less than 18 years, a second ACL injury (ACL graft or CACL injury) occurred in 1 in 3 patients. The 5-year survival rate of the ACL graft was 76%, and the 5-year survival rate of the CACL was 86%. High IKDC scores and continued participation in sports were maintained over the medium term. Importantly, there was favorable survival of the ACL graft in patients with Tanner stage 1-2 compared with patients with Tanner stage 3-5 over 5 years. Patients with Tanner stage 1-2 also had a significantly lower incidence of second ACL injuries over 5 years compared with those with Tanner stage 3-5, occurring in 1 in 5 patients. Thus, an LDHT graft from a parent is an appropriate graft for physically immature children.

Clinical Outcome Measures and Return-to-Sport Timing in Adolescent Athletes After Anterior Cruciate Ligament Reconstruction

CONTEXT

  Multiple factors are likely associated with an adolescent athlete's ability to return to play after anterior cruciate ligament (ACL) reconstruction (ACLR).

OBJECTIVE

  To investigate the relationship between self-reported and functional outcome measures on return-to-play timing in an adolescent population, in athletes who returned and those who did not return to sport, and to identify a cutoff value for isometric quadriceps strength that could serve as a clinical target for maximizing the odds of returning to play after ACLR.

DESIGN

  Cross-sectional study.

SETTING

  Outpatient clinic.

PATIENTS OR OTHER PARTICIPANTS

  Adolescent athletes who underwent ACLR and completed clinical measures at their 3- and 6-month follow-up appointments were included.

MAIN OUTCOME MEASURE(S)

  Clinical measures included functional outcomes of isometric and isokinetic strength tests and the Anterior Cruciate Ligament Return to Sport After Injury scale and the pediatric version of the International Knee Documentation Committee subjective form. Physician clearance dates for return to play were obtained from patient records.

RESULTS

  Higher strength measures were associated with better scores on the Anterior Cruciate Ligament Return to Sport After Injury and the pediatric version of the International Knee Documentation Committee instruments at each follow-up. Differences were found in isometric extension strength ( P = .001) and isokinetic extension strength at 180°/s ( P = .03) and 300°/s ( P = .002) between patients who returned to sports and those who did not. A 6-month isometric extension deficit (mean Limb Symmetry Index = 85.48 ± 23.15) displayed high accuracy (area under the curve = 0.82, 95% confidence interval = 0.68, 0.95) for identifying patients who returned to play after ACLR.

CONCLUSIONS

  Higher strength measures at both 3 and 6 months after ACLR were associated with greater self-reported knee function and greater readiness to return to functional activities at 6 months and ultimately earlier return to sport in adolescent athletes. These results provide evidence that self-reported outcome scores should be used as an additional screening tool in conjunction with quadriceps strength testing to help provide realistic recovery timeframes for adolescent patients.

Anterior Cruciate Ligament Reconstruction in Skeletally Immature Patients: Early Results Using a Hybrid Physeal-Sparing Technique

Background:

Reconstruction of the anterior cruciate ligament (ACL) in the skeletally immature patient is frequently performed in hopes of preventing new or additional chondral damage and meniscal injuries. Patients within a few years of skeletal maturity are more at risk for ACL injuries than prepubescent patients, about whom several physeal-sparing techniques have been described. Reconstruction techniques in the former higher risk group need to be better understood.

Purpose:

To review a series of adolescent patients with ACL injuries surgically treated with the hybrid physeal-sparing technique.

Study Design:

Case series; Level of evidence, 4.

Methods:

Surgical logs of ACL reconstructions (ACLRs) performed at a single pediatric/adolescent sports medicine center over a 6-year period were reviewed. Patients with open physes who had undergone ACLR with a femoral physeal-sparing tunnel and transphyseal tibial tunnel were identified. Their demographics, operative reports, rehabilitative course, time to return to play, outcome scores, and postoperative radiographs were collected and analyzed.

Results:

Twenty-three patients with a mean chronological age and bone age of 13.0 and 13.6 years, respectively, were identified. Examination and subjective outcome scores were obtained at a mean of 19 months and overall demonstrated positive results, with a mean Pediatric International Knee Documentation Committee (Pedi-IKDC) score of 96.0 and a mean Anterior Cruciate Ligament–Return to Sport after Injury (ACL-RSI) score of 89.1. Full-length mechanical axis films obtained at a mean 21 months postoperatively demonstrated no leg-length discrepancies or angular deformities in 21 of 23 patients. Two patients had an identified growth disturbance in the form of femoral and tibial growth acceleration on the ACL-reconstructed limb.

Conclusion:

The femoral physeal-sparing with transphyseal tibial drilling “hybrid” technique in skeletally maturing patients appears to have a high rate of success with low morbidity. However, the possibility of physeal abnormalities does exist, which demonstrates the importance of a close postoperative follow-up and evaluation until skeletal maturity is achieved. ACLR in skeletally immature patients is performed on an increasingly regular basis. Establishing the best and safest technique to do so is therefore important.

Arthroscopic Fixation of Tibial Spine Avulsion in Skeletally Immature: The Technique

INTRODUCTION

Tibial spine avulsion fracture is more frequent in children than adults. Various methods of fixation have been mentioned, but concern remains about crossing the tibial physis. We present a technique of arthroscopic fixation with non-absorbable suture.

CASE REPORT

A total of 10 skeletally immature patients with tibial spine avulsion of Meyers and McKeever Type 2 and 3 were included in the study. The knee was arthroscopically cleared of hematoma. The avulsed tibial insertion of anterior cruciate ligament was reduced and held in place with tibial guide. By drilling guide wire through the tibia, reduced fragment, a fiber wire was passed. The avulsed fragment was tied on a suture post on tibia. Outcome was evaluated radiologically and clinically (Lysholm score, pivot shift, and KT 1000) at 12 months after surgery. All cases attained full range of motion, stable knee and could return to previous level of activity. The mean pre-operative Lysholm score of 50.8 ± 1.4 (35-59) improved to 96.3 ± 2.9 (92-100). The mean pre-operative anterior translation of tibia (measured by KT 1000) of 7.6 ± 1.26 improved significantly to mean of 3.3 ± 0.82 mm after surgery.

CONCLUSION

The presented technique of arthroscopic fixation of avulsed tibial spine is a simple technique that provides reproducible results. It also offers cost-effective secure fixation.

Ankylosis of the knee after septic arthritis following anterior cruciate ligament reconstruction in a 13-year-old male

We present the case of an adolescent male developing an ankylosis of the knee after septic arthritis following anterior cruciate ligament reconstruction (ACLR). The patient was shifted to our institution with postoperative septic arthritis associated with a systemic septic condition. Before, repeated arthroscopic surgery had been conducted without any improvement. MRI showed a concomitant osteomyelitis. The infection (Gächter IV, Staphylococcus aureus) was controlled by an open surgical approach and graft removal. An increasing joint stiffness was documented. X-rays showed an ankylosis at 30° of flexion and early closure of growth plates. Functional knee scores showed significantly worse results. Early diagnosis and a stage-adapted treatment in septic arthritis following ACLR are mandatory. In advanced stages or concomitant osteomyelitis an open approach and graft removal may be appropriate. The antibiotic treatment should be adapted consistently.

Return to sport activity after anterior cruciate ligament reconstruction in skeletally immature athletes with manual drilling original all inside reconstruction at 8 years follow-up

Objective

Anterior cruciate ligament (ACL) tears are common injuries in adolescent athletes, especially in those who bear high stress on their knees due to shearing forces. The goal of the surgical procedures in skeletally immature patients is to restore joint stability avoiding the adverse effects on the growth process.

The aim of this study was to verify the return of the skeletally immature professional athletes to sports in the long-term, following ACL reconstruction with the original all-inside technique and with manual drilling.

Methods

This study included 24 athletes (14 boys, 10 girls; mean age: 13.15 years, range: 9–14 years) who had radiographic evidence of open physes, were less than 14 years of age at the time of surgery and those with a minimum follow-up of eight years. All patients completed a questionnaire, the IKDC subjective knee evaluation form, and Tegner Activity Scale. Biomechanical outcomes of the KT-1000 arthrometer, gait analysis, and stabilometric and isokinetic results were also evaluated. A plain radiograph of both lower limbs was taken to obtain a precise measurement of the limb length and mechanical axis angles.

Results

The patients returned to sport activities in a mean time of 6.43 months. No rerupture or resurgery due to growth abnormalities was observed. The mean difference in length between the operated and contralateral legs was 0.4 (range: −0.2 to 0.7) cm. The mean side-to-side difference measured with the KT-1000 arthrometer was 5.2 (range: 3.5 to 7) mm in the preoperative and 0.8 (range: 0 to 2.5) mm in the postoperative measurements.

Conclusion

In conclusion, the original all-inside technique with manual drilling with a half tunnel and short graft seems to be a very effective technique for the surgical management of ACL injuries in pediatric/adolescent athletes. A good rate of return to sports at pre-injury levels or higher, high patient satisfaction and a decent motor and proprioceptive function is possible as shown by our analysis.

Level of evidence

Level IV, Therapeutic study.

Arthroscopic transphyseal anterior cruciate ligament reconstruction in adolescent athletes

PURPOSE

To evaluate the 5-year outcome of arthroscopic transphyseal anterior cruciate ligament (ACL) reconstruction in 19 adolescent athletes.

METHODS

14 male and 5 female adolescent athletes aged 12 to 16 (mean, 13.9) years with Tanner stage 2 or 3 open physes underwent arthroscopic transphyseal ACL reconstruction by a single surgeon and were followed up for 5 years. Patients were evaluated using the numerical rating score (NRS) for pain, knee osteoarthritis outcome score (KOOS), International Knee Documentation Committee (IKDC) score, Tegner Activity Scale, and Lysholm Score, as well as the leg length discrepancy, femorotibial alignment, varus or valgus deformities, active and passive knee range of motion.

RESULTS

At 5-year follow-up, physes were closed in all patients. The mean NRS for pain improved from 7.2 to 1.6; the KOOS improved from 55.3 to 88; the mean IKDC score improved from 34.5 to 84; the mean Tegner Activity Scale improved from 2.7 to 8.2 and was comparable with that before injury (8.4); and the mean Lysholm score improved from 36.3 to 84.6. All except 2 patients returned to their pre-injury level of sports activity after a mean of 25 weeks. The 2 exceptions had a 2+ Jerk test and a 3+ Lachman test; one of them also had positive signs for a lateral meniscal lesion. Both had sustained a second trauma not long before the 5-year follow-up. Two patients had reduced sensitivity in the anteromedial aspect of the proximal third of the tibia. One patient had leg length discrepancy of +1.5 cm owing to overgrowth response of the physis.

CONCLUSION

Transphyseal ACL reconstruction is a viable option for skeletally immature patients, with high reproducibility, a high rate of return to sport, and a low incidence of growth disturbance. Early surgery can prevent the onset of meniscal lesions and early osteoarthritis.

A Comparative Analysis of International Knee Documentation Committee Scores for Common Pediatric and Adolescent Knee Injuries

BACKGROUND

Several different etiologies cause knee pain in the pediatric and adolescent population, including anterior knee/patellofemoral pain, patellar instability, anterior cruciate ligament (ACL) tears, meniscal tears, osteochondritis dissecans (OCD) lesions, and discoid meniscus. The purpose of the current study was to determine the relative morbidity of different causes of knee pain in children and adolescents using the International Knee Documentation Committee (IKDC) score.

METHODS

We performed a retrospective review of prospectively collected data of a cohort of pediatric and adolescent patients with knee pain who presented to a single surgeon. Each patient completed an IKDC questionnaire at the time of diagnosis and patients were grouped by diagnosis for analysis. Statistical analysis was performed to compare the IKDC scores of the 7 diagnostic groups, and a P-value <0.05 was considered significant.

RESULTS

The IKDC mean score for all 242 patients was 50.3±18.3. The mean IKDC score for patients with isolated meniscal tears was 41.2±16.0, combined ACL and meniscal injuries was 50.2±13.9, and isolated ACL tears was 48.1±14.1. The mean IKDC score for patients with symptomatic discoid meniscus was 46.3±13.2, anterior knee pain/patellofemoral pain was 49.0±17.4, patellar instability was 49.2±22.1, and OCD lesions was 62.2±19.5.

CONCLUSIONS

The IKDC scores of most of the diagnostic groups were similar to the overall average score, with the notable exception of patients with OCD lesions exhibiting statistically significant less morbidity reflected by a higher IKDC score. Although symptoms in each individual clinical presentation may vary, knowledge of the relative morbidity of these diagnostic groups is valuable in counseling patients and their families regarding these common pediatric and adolescent sources of knee pain.

LEVEL OF EVIDENCE

Level IV.

Growth Abnormalities Following Anterior Cruciate Ligament Reconstruction in the Skeletally Immature Patient: A Systematic Review

PURPOSE

To identify all reported cases of growth disturbances after anterior cruciate ligament (ACL) reconstruction in patients with open growth plates and analyze trends with respect to different surgical techniques, graft choices, and methods of fixation.

METHODS

A systematic literature review was conducted using the MEDLINE, EMBASE, and SCOPUS databases with the following term: "((anterior cruciate ligament OR ACL) AND ((((immature) OR growth plates) OR physes) OR pediatric))." Only studies that evaluated ACL reconstruction in patients with open growth plates and reported angular malformations or limb length discrepancy were included. Data were extracted, including patient characteristics, surgical technique, and postoperative growth disturbance.

RESULTS

Twenty-one studies containing 39 patients with growth abnormalities were included in the review. Mean chronological age was 13 years, and 89% of patients were male. Overall, there were 16 cases of angular malformations and 29 cases of limb length discrepancy. The most common angular malformation was genu valgum (81%, n = 13; mean of 6.5°). The most common surgical technique on the tibia and femur was transphyseal (54%, and 77% respectively), and the most common graft used was hamstring autograft (58%). Among patients with limb length discrepancy, overgrowth was most common (62%, n = 18; mean of 13 mm). Interestingly, we observed that 50% of patients with overgrowth underwent a physeal-sparing technique, whereas 64% of patients with shortening underwent a transphyseal technique.

CONCLUSIONS

At present, there are 21 studies reporting 39 patients with growth abnormalities in the current literature, of which 29 cases were of limb length discrepancy and 16 of angular malformation. Of the 29 cases of limb length discrepancy, limb overgrowth accounted for 62% of cases. Perhaps most interestingly, physeal-sparing techniques were performed in 25% of the cases of angular malformation and 47% cases of limb length discrepancy, despite the commonly held belief that this technique mitigates the risks of ACL reconstruction by not violating the growth plate. According to this study, it is clear that growth abnormalities after ACL reconstruction in the skeletally immature patient are underreported, and our current understanding of the etiology of these abnormalities is limited.

LEVEL OF EVIDENCE

Level IV, systematic review of Level II to IV studies.

Tibial tunnel defect size as a risk factor in growth arrest following paediatric transphyseal anterior cruciate ligament reconstruction: an anatomical study

BACKGROUND

There is ongoing controversy regarding growth disturbances in younger patients undergoing anterior cruciate ligament reconstructions. Animal models have shown that an injury of 7-9% of the physeal area is a risk factor for growth disturbances.

METHODS

A total of 39 magnetic resonance imaging studies of the knee were examined. The proximal tibial physeal area was determined using a calibrated 'region of interest' ligature encompassing the tibial physis in the axial plane. The potential defect left by commonly used drill sizes was calculated as a percentage of the physeal area.

RESULTS

A 7-mm drill leaves a mean defect of 1.45% physeal area (range: 1.11-1.89%, SD: 0.28, 95% CI: ±0.09), 8-mm drill leaves a 1.84% mean defect (range: 1.43-2.49%, SD: 0.38, 95% CI: ±0.12) and a 9-mm drill leaves a 2.30% mean defect (range: 1.83-3.19%, SD: 0.58, 95% CI: ±0.17). At 55°, 7-mm drill leaves a mean defect of 1.96% (range: 1.32-2.28%, SD: 0.37, 95% CI: ±0.12), 8-mm drill leaves a mean defect of 2.19% (range: 1.71-2.95%, SD: 0.46, 95% CI: ±0.14) and a 9-mm drill leaves a mean defect of 2.76% (range: 2.16-3.73%, SD: 0.58, 95% CI: ±0.18). There was a statistically significant difference in the tunnel area with a change of drill angle (7-mm drill P = 0.005, 8-mm drill P = 0.001, 9-mm drill P = 0.001).

CONCLUSION

On the basis of this study in the context of animal model and observational evidence, the area of physeal injury using drill tunnels for anterior cruciate ligament reconstruction would not appear to contribute to potential growth disturbances.

A systematic review and meta-analysis of the diagnostic accuracy of MRI for suspected ACL and meniscal tears of the knee

PURPOSE

To determine the diagnostic accuracy of magnetic resonance imaging (MRI) and ultrasound (US) in the diagnosis of anterior cruciate ligament (ACL), medial meniscus and lateral meniscus tears in people with suspected ACL and/or meniscal tears.

METHODS

MEDLINE, Web of Science and the Cochrane library were searched from inception to March 2014. All prospective studies of the diagnostic accuracy of MRI or US against arthroscopy as the reference standard were included in the systematic review. Studies with a retrospective design and those with evidence of verification bias were excluded. Methodological quality of included studies was assessed using the QUADAS-2 tool. A meta-analysis of studies evaluating MRI to calculate the pooled sensitivity and specificity for each target condition was performed using a bivariate model with random effects. Sub-group and sensitivity analysis were used to examine the effect of methodological and other study variables.

RESULTS

There were 14 studies included in the meta-analysis of the accuracy of MRI for ACL tears, 19 studies included for medial meniscal tears and 19 studies for lateral meniscal tears. The summary estimates of sensitivity and specificity of MRI were 87 % (95 % CI 77-94 %) and 93 % (95 % CI 91-96 %), respectively, for ACL tears; 89 % (95 % CI 83-94 %) and 88 % (95 % CI 82-93 %), respectively, for medial meniscal tears; and 78 % (95 % CI 66-87 %) and 95 % (95 % CI 91-97 %), respectively, for lateral meniscal tears. Magnetic field strength had no significant effect on accuracy. Most studies had a high or unclear risk of bias. There were an insufficient number of studies that evaluated US to perform a meta-analysis.

CONCLUSION

This study provides a systematic review and meta-analysis of diagnostic accuracy studies of MRI and applies strict exclusion criteria in relation to the risk of verification bias. The risk of bias in most studies is high or unclear in relation to the reference standard. Concerns regarding the applicability of patient selection are also present in most studies.

LEVEL OF EVIDENCE

III.

A physeal-sparing fibular collateral ligament and proximal tibiofibular joint reconstruction in a skeletally immature athlete

The purpose of this report was to describe the surgical technique for and outcomes after a modified physeal-sparing posterolateral corner reconstruction in a 12-year-old skeletally immature male with a mid-substance fibular collateral ligament tear, a proximal posterior tibiofibular ligament tear, and an anterior cruciate ligament avulsion fracture of the medial tibial eminence. A modified physeal-sparing posterolateral corner reconstruction was used to provide a near-anatomic reconstruction of the fibular collateral ligament and proximal posterior tibiofibular ligament. An anterior cruciate ligament repair was also performed. Varus stress radiographs obtained at 6 months postoperatively demonstrated resolution of lateral knee stability. Physical examination results demonstrated stability to anterior tibial translation and a stable proximal tibiofibular joint. Computed tomography showed that the surgical technique successfully avoided breeching the patient's physes.

Symmetric limb overgrowth following anterior cruciate ligament reconstruction in a skeletally immature patient

This report describes a case of symmetric femoral and tibial overgrowth of 2.8 cm in a 13-year-old patient after undergoing reconstruction surgery for his torn right anterior cruciate ligament. A literature review of previous cases is also provided. Following a pediatric anterior cruciate ligament tear, delaying surgery until the patient approaches skeletal maturity may avoid long-term growth disturbances, however, delaying this procedure may increase the probability of further joint damage. This growth disturbance was managed with a percutaneous epiphysiodesis that corrected the limb length deformity.

Surgical-experimental principles of anterior cruciate ligament (ACL) reconstruction with open growth plates

Objective

To review surgical and animal experimental studies performed with open growth plates in relation with pediatric anterior cruciate ligament (ACL) reconstruction.

Backround

When it comes to the treatment of ACL injured children, there is a lack of current international guidelines, leaving the treating physicians with a therapeutic dilemma. A variety of surgical and animal experimental studies have been undertaken over the last decades in relation with open growth plates and ACL-reconstruction.

Method

Based on our own previous animal experimental data, we highlighted 15 specific points concerning pediatric ACL-reconstruction and reviewed additional literature concerning these individual items.

Results

Pediatric ACL-reconstruction could be proven to be safe in animal models. Growth abnormalities, risk factors and factors, which were specifically related to biological healing processes in children, were identified. From them surgical principles for safe pediatric ACL replacements can be deducted. Applying these principles through a correct technical execution of surgery may prevent clinically significant growth changes.

Conclusion

Over the last 2 decades it has been shown that a technically correct pediatric ACL reconstruction has little risk in creating clinically significant growth abnormalities. Animal experiments support this hypothesis despite the fact that the gained knowledge cannot be fully generalized to humans. More long time follow-up is needed to fully understand the complete risk factors related to ACL surgery with open growth plates.

Electronic supplementary material

The online version of this article (doi:10.1186/s40634-015-0027-z) contains supplementary material, which is available to authorized users.

Anterior cruciate ligament injuries in adolescents with open physis: effect of recurrent injury and surgical delay on meniscal and cartilage injuries

BACKGROUND

Treatment choices for skeletally immature patients sustaining anterior cruciate ligament (ACL) injuries have been controversial. The main dilemma is whether surgical treatment should be provided before patients reach skeletal maturity or whether nonoperative treatment should be provided until the physis has closed. Surgical reconstruction risks physeal damage, while delaying surgery may increase menisci and cartilage damage.

PURPOSE

To identify patients at the onset of ACL injury and follow them longitudinally to surgery or final follow-up to describe differences between nonoperative and operative patients and to analyze the effect of delayed reconstruction.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A retrospective review of patients enrolled at a large integrated health care system (IHS) between January 1, 2005, and December 31, 2008, was performed. The study sample included all females ≤12 years old and males ≤14 years old who were evaluated with an ACL injury. The incidence of ACL injuries in each age group was calculated using the number of covered lives by the IHS system per age category as the denominator. Each patient was longitudinally followed using an electronic health record that captures all patient encounters. Every encounter was reviewed for symptoms associated with the index knee, and encounters were considered significant if new-onset pain or swelling was reported. Patients were instructed to restrict their activities while awaiting skeletal maturity to undergo reconstruction by not participating in activities that included any cutting or pivoting movements that would risk injury to the knee. Cartilage and meniscal injuries were recorded for patients who underwent reconstruction.

RESULTS

A total of 71 patients were identified during the study period (66 males, 4 females). At the completion of this study, 47 (66.2%) patients had undergone ACL reconstruction, and 24 (33.8%) were being treated nonoperatively. While there were no significant associations between time to surgery and meniscal or cartilage injury, there was a positive association between the number of significant encounters and the likelihood of a combined cartilage and meniscal injury (P = .01).

CONCLUSION

This is the first study to measure the incidence of ACL injuries in a skeletally immature population. For patients undergoing ACL reconstruction, an increased number of significant encounters was statistically significantly associated with combined meniscal and cartilage injuries, while increased time from injury to surgery was not significantly associated with additional injuries. In addition, one-third of the patients continued nonoperative treatment without symptoms that warranted surgical interventions during the follow-up period.

Anterior cruciate ligament reconstruction in children with a quadrupled semitendinosus graft: preliminary results with minimum 2 years of follow-up

BACKGROUND

The management of anterior cruciate ligament (ACL) tears in growing patients must balance activity modification with the risk of secondary (meniscal and cartilaginous) lesions, and surgical intervention, which could adversely affect skeletal growth. Many ACL reconstruction techniques have been developed or modified to decrease the risk of growth disturbance. We have not found any description of ACL reconstruction using a single hamstring, short graft implanted into intraepiphyseal, retroreamed sockets. Our hypothesis was that the technique that we used restored the knee stability and did not cause any growth disturbances.

METHODS

We retrospectively studied 28 patients (20 boys, 8 girls) who presented with a unilateral ACL tear and open growth plates. We performed short graft ligament reconstruction with the semitendinosus folded into 4 strands around 2 polyethylene terephthalate tapes. The graft was implanted into sockets that were retroreamed in the femoral and tibial epiphysis and the tapes were fixed remotely by interference screws. After a minimum period of 2 years, we evaluated the comparative knee laxity, the radiographic limb morphology, the appearance of secondary lesions, and the functional outcomes using the Lysholm and Tegner scores. Comparative analyses were performed using the Student t test with subgroups depending on the type of fixation used.

RESULTS

The mean age of the patients was 13 years (range, 9 to 15 y). The mean follow-up was 2.8 years (range, 2 to 5 y). The mean difference in laxity at 134 N was 0.3 mm, as determined using a GNRB arthrometer. No patients reported meniscal symptoms or degenerative changes. We found no angular deformity or leg length inequality. Two patients suffered a recurrent ACL tear.

CONCLUSIONS

The preliminary results from this series are consistent with prior studies demonstrating that intraepiphyseal ACL reconstruction is a safe reliable alternative for the pediatric population.

STUDY DESIGN

Case series; level of evidence 4.