Effect of Graft Type on Balance and Hop Tests in Adolescent Males Following Anterior Cruciate Ligament Reconstruction

Assessment of Return to Sport After ACL Reconstruction With Soft Tissue Autograft in Adolescent Athletes: Quadriceps Versus Hamstring Tendon

Background

Quadriceps tendon soft tissue autograft represents an increasingly popular graft option for anterior cruciate ligament reconstruction (ACLR), particularly for adolescents, some of whom have an open physis, precluding use of graft options with bone plugs.

Purpose/Hypothesis

The purpose of this study was to quantify return-to-sport performance assessments in adolescents at 6 months after ACLR with all-soft tissue quadriceps tendon autograft (ACLR-Q) versus hamstring tendon autograft (ACLR-HS). It was hypothesized that ACLR-Q would be associated with improved hamstring strength and hamstring-to-quadriceps (HS:Q) ratios compared with ACLR-HS, albeit with decreased quadriceps strength.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Included were patients aged 12 to 19 years who underwent primary ACLR by a single surgeon and who completed a return-to-sport performance assessment between 5 and 9 months postoperatively. The performance assessment included manual muscle strength tests (hamstring, quadriceps, hip abductor and adductor), dynamic balance test (Y-balance), and functional hop tests (single hop, triple hop, crossover hop, 6-m timed hop). Data were converted to limb symmetry indices, and limb symmetry index deficits were compared between the ACLR-Q and ACLR-HS cohorts using the Student t test or Wilcoxon-Mann-Whitney test.

Results

An initial cohort of 90 ACLR-Q patients was compared with 54 ACLR-HS patients, with no significant differences in patient characteristics. Differences in meniscal repair rates, however, prompted use of propensity score matching on age, sex, body mass index, meniscectomy, and meniscal repair to produce comparable subcohorts. The matching resulted in 67 ACLR-Q and 52 ACLR-HS patients. Hamstring strength deficits were significantly greater in ACLR-HS versus ACLR-Q patients (-40.5% vs -5.7%; P < .001). Quadriceps strength deficits were significantly greater in ACLR-Q versus ACLR-HS patients (-12.8% vs -0.4%; P < .001). ACLR-Q patients had a significantly greater HS:Q ratio on the operative knee (P < .001) and significantly higher Y-balance composite score deficits (-2.9% vs -0.4%; P = .01) than ACLR-HS patients. There were no significant differences in hop test performance between groups.

Conclusion

Adolescent athletes who underwent ACLR-Q showed significantly greater quadriceps strength deficits but significantly smaller hamstring strength deficits than those who underwent ACLR-HS, leading to more favorable HS:Q ratios in ACLR-Q patients at 6 months postoperatively.

Reconsideration of Return-to-Sport Decision-Making After Pediatric ACL Injury: A Scoping Review

CONTEXT

Up to 90% of pediatric athletes return to sport (RTS) after anterior cruciate ligament reconstruction (ACL-R); however, <50% RTS at the same level and second ACL injury rates are up to 32%.

OBJECTIVES

(1) Determine which physical and patient-reported outcome measures guide clinical decision-making on RTS in pediatric athletes after ACL-R and (2) present a framework with insights from cognitive and neurophysiological domains to enhance rehabilitation outcomes.

DATA SOURCES

PubMed, CINAHL, Embrase, and Cochrane library databases and gray literature.

STUDY SELECTION

Data on pediatric (<18 years) ACL-R patients, RTS, tests, and decision-making were reported in 1214 studies. Two authors independently reviewed titles and abstract, excluding 962 studies. Gray literature and cross-reference checking resulted in 7 extra studies for full-text screening of 259 studies. Final data extraction was from 63 eligible studies.

STUDY DESIGN

Scoping review.

LEVEL OF EVIDENCE

Level 4.

DATA EXTRACTION

Details on study population, aims, methodology, intervention, outcome measures, and important results were collected in a data chart.

RESULTS

Studies included 4456 patients (mean age, 14 years). Quadriceps and hamstring strength (n = 25), knee ligament arthrometer (n = 24), and hop tests (n = 22) were the most-reported physical outcome measures guiding RTS in <30% of studies with cutoff scores of limb symmetry index (LSI) ≥85% or arthrometer difference <3 mm. There were 19 different patient-reported outcome measures, most often reporting the International Knee Documentation Committee (IKDC) (n = 24), Lysholm (n = 23), and Tegner (n = 15) scales. Only for the IKDC was a cutoff value of 85% reported.

CONCLUSION

RTS clearance in pediatric ACL-R patients is not based on clear criteria. If RTS tests were performed, outcomes did not influence time of RTS. Postoperative LSI thresholds likely overestimate knee function since biomechanics are impaired despite achieving RTS criteria. RTS should be considered a continuum, and biomechanical parameters and contextual rehab should be pursued with attention to the individual, task, and environment. There is a need for psychological monitoring of the ACL-R pediatric population.

Influence of Graft Type on Lower Extremity Functional Test Performance and Failure Rate After Anterior Cruciate Ligament Reconstruction

BACKGROUND

Both autografts and allografts are used to reconstruct the anterior cruciate ligament (ACL) after injury; however, it is unclear whether graft source affects lower extremity functional test performance or failure rate in an active military population.

OBJECTIVE

To compare lower extremity functional test performance and graft failure rates between ACL grafts [allograft, hamstring, bone-patellar tendon-bone (BTB)].

STUDY DESIGN

Cross-sectional.

LEVEL OF EVIDENCE

Level 2.

METHODS

Ninety-eight cadets entering a US Service Academy with a history of unilateral ACL reconstruction (ACLR) agreed to participate. Before basic training, participants completed 4 lower extremity functional tests. Active injury surveillance was conducted within the study cohort to identify all subsequent graft failures.

RESULTS

Cadets with hamstring autografts outperformed the BTB and allograft groups on the Lower Quarter Y-Balance Test-Posteromedial direction and single-leg hop test, respectively. No differences were detected by graft type for the other functional tests. The incidence of subsequent ipsilateral graft failures in patients with autograft was 8.11%. No failures were observed in the allograft group during the follow-up period. After controlling for sex, joint hypermobility, and time since injury and surgery, the risk of graft failure was 9.8 times higher for patients with a hamstring autograft than with a BTB (P = 0.045).

CONCLUSION

After ACLR, graft type appears to influence some single-limb measures of lower extremity function and the risk of subsequent failure. Hamstring autografts demonstrated better functional performance but increased risk of graft failure.

CLINICAL RELEVANCE

Surgeons need to weigh the pros and cons of all graft options in relation to the patient's lifestyle. Regardless of graft type, individuals with an ACLR may require additional rehabilitation to regain neuromuscular control during dynamic single-limb tasks and mitigate graft failure.

Deficits in Dynamic Balance and Hop Performance Following ACL Reconstruction Are Not Dependent on Meniscal Injury History

Background

Athletes often exhibit persistent deficits in dynamic balance and hop performance in their involved limb following ACL reconstruction. However, it is unclear how meniscal injury history affects inter-limb asymmetry.

Purpose

The purpose of this study was to compare inter-limb asymmetry in dynamic balance and hop performance in athletes with and without a history of concomitant meniscal injury.

Study Design

Cross-sectional study.

Methods

Dynamic balance and hop test data were analyzed for 34 adolescent athletes who had undergone ACL reconstruction; 19 athletes had sustained an isolated ACL tear, while 15 had sustained an ACL tear along with a meniscus injury. Athletes who had sustained a meniscus injury were sub-divided into those who underwent a meniscal repair (n = 9) versus a partial meniscectomy (n = 6). Dynamic balance was assessed using the Y-Balance Test, while hop performance was assessed using the single and triple hop tests. Data were recorded at the time of return-to-sport testing (5-11 months post-surgery). For each variable, mixed-model analysis of variance, with a between-subjects factor of group (isolated ACL tear, meniscal repair, partial meniscectomy) and a within-subjects factor of limb (involved, uninvolved), was conducted.

Results

The groups exhibited similar degrees of inter-limb asymmetry in dynamic balance and hop test performance, as there was not a group-by-limb interaction effect for the Y-Balance Test distances (p ≥ 0.43) or hop test distances (p ≥ 0.96). However, there was a main effect of limb for the anterior and posteromedial Y-Balance Test distances and the single and triple hop test distances (p ≤ 0.004). For each variable, performance was worse for the involved limb, compared to the uninvolved limb.

Conclusion

It appears that deficits in dynamic balance and hop performance among adolescent athletes who have undergone ACL reconstruction are not dependent on meniscal injury/surgery history.

Level of Evidence

3.

Quadriceps tendon autograft for pediatric anterior cruciate ligament reconstruction results in promising postoperative function and rates of return to sports: A systematic review

PURPOSE

To assess the performance of the quadriceps tendon (QT) autograft in pediatric anterior cruciate ligament reconstruction (ACLR).

METHODS

A systematic search of MEDLINE, PubMed, and EMBASE was conducted on March 1, 2021. Studies of all levels of evidence reporting outcomes and/or complications after QT autograft ACLR in pediatric patients (≤ 18 years old) were eligible for inclusion. Study demographics, patient demographics, reported outcomes, and complications were abstracted. Screening and data abstraction were designed in accordance with PRISMA and R-AMSTAR guidelines. Descriptive statistics were presented when applicable, with data for heterogeneous outcomes presented in narrative summary fashion.

RESULTS

A total of 14 studies examining 596 patients (46.3% female), mean age 15.4 years, were included in this systematic review. Mean postoperative Lysholm scores ranged from 94.0 to 99.5. Mean postoperative IKDC subjective scores ranged from 75.9 to 94.0. Limb symmetry index ranged from 96.8 ± 10.4 to 100.4 ± 7.6% across multiple hop tests. Return to sports (RTS) rates ranged from 88.9 to 91.7%. Eleven studies reported postoperative complications, whereby 16 patients (4.8%) experienced contralateral complications and injuries. Forty-six patients (9.4%) experienced ipsilateral complications, including ten graft failures (2.5%) and two growth disturbances (0.6%).

CONCLUSIONS

QT autograft ACLR in the pediatric population retains the potential of regaining a preinjury level of knee stability, and yields promising postoperative function and rates of RTS, yielding comparable outcomes relative to HT autograft and the reference-standard BPTB ACLR that have previously been described in the literature. Moreover, use of the QT autograft is associated with low rates of postoperative complications, including graft failure and growth disturbances in this active and high-risk patient population in observational studies to date. Therefore, clinical equipoise exists to further appraise the influence of QT autograft on postoperative outcomes compared to aforementioned autograft options in a randomized control trial fashion.

LEVEL OF EVIDENCE

IV.

Limited evidence for graft selection in pediatric ACL reconstruction: a narrative review

Anterior cruciate ligament reconstruction is the preferred treatment to anterior cruciate ligament injury. With the increase in anterior cruciate ligament injuries in both adults and skeletally immature patients comes the need for individualized anterior cruciate ligament reconstruction graft selection whether it is the type of graft (auto vs. allograft) or the harvesting site (hamstrings, iliotibial band, quadriceps, patella). Several factors need to be considered preoperatively in order to optimize the patients’ recovery and restore anterior cruciate ligament strength and function. These include age and bone maturity, preoperative knee flexor/extensor strength, sport participation, patient’s needs and anatomical characteristics. This paper aims at bringing evidence supporting the use of a personalized approach in graft selection for faster and more efficient return to sport and propose a theoretical framework to support the approach.

Long-Term Follow-up of Skeletally Immature Patients With Physeal-Sparing Combined Extra-/Intra-articular Iliotibial Band Anterior Cruciate Ligament Reconstruction: A 3-Dimensional Motion Analysis

BACKGROUND

The physeal-sparing iliotibial band (ITB) anterior cruciate ligament (ACL) reconstruction (ACLR) is a well-established technique for treating skeletally immature patients with ACL rupture. However, the long-term implications of the procedure on the intricacies of kinetic and kinematic function of the knee have not been comprehensively investigated.

PURPOSE

To assess the short-, mid-, and long-term effects of ITB ACLR on kinetic and kinematic parameters of knee functions.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 38 patients who had undergone an ITB ACLR as a skeletally immature child were recruited to participate in a 3-dimensional (3D) motion analysis testing protocol at an institutional injury prevention center between 1 and 20 years after reconstruction. Exclusion criteria were congenital ACL deficiency and any other major knee injury (defined as an injury requiring surgery or rehabilitation >3 months) on either knee. 3D and force plate parameters included in the analysis were knee moment, ground-reaction force, and vertical jump height measured during drop vertical jump and vertical single-limb hop. Paired t tests and equivalency analyses were used to compare the parameters between cases (ITB ACLR limb) and controls (contralateral/nonsurgical limbs).

RESULTS

Paired t tests showed no statistically significant differences between limbs, and equivalency analyses confirmed equivalency between limbs for all tested outcome variables.

CONCLUSION

The ITB ACLR appears to restore normal, symmetric, physiologic kinetic and kinematic function in the growing knee by 1 year after reconstruction, with maintenance of normal parameters for up to 20 years.

Effects of Maturation on Lower Limb Neuromuscular Asymmetries in Elite Youth Tennis Players

Neuromuscular asymmetries have been previously associated with reduced performance. Similarly, maturation has shown that youth athletes may experience a loss of motor control, which could also lead to compromised physical performance. The present study aimed to evaluate and quantify the level of asymmetry among chronological and maturational groups. Forty-one youth tennis players performed the single leg countermovement jump (SLCMJ), star excursion balance test (SEBT) and a change of direction speed (CODS) test. Differences were found between the strongest and weakest limbs across all tests (p < 0.001), and also for SEBT in the posteromedial direction (p = 0.02), SEBT composite score (p < 0.01) in maturation groups, and for SEBT posterolateral direction (p = 0.03) and SEBT composite score (p = 0.01) in chronological groups. The SLCMJ showed the largest inter-limb asymmetries for the circa peak height velocity (PHV) group (19.31 ± 12.19%) and under-14 (U14) group (17.55 ± 9.90%). Chronological and maturation groups followed similar trends for inter-limb asymmetries, but the biological index showed larger asymmetry scores in the jumping test at PHV compared to that found in the chronological group (U14). These results show that inter-limb differences may be heightened during PHV. Practitioners can use this information to inform the decision-making process when prescribing training interventions in youth tennis players.