Utilization of Modified NFL Combine Testing to Identify Functional Deficits in Athletes Following ACL Reconstruction

Abstract

STUDY DESIGN Case control. OBJECTIVES To use modified NFL Combine testing methodology to test for functional deficits in athletes following anterior cruciate ligament (ACL) reconstruction following return to sport. BACKGROUND There is a need to develop objective, performance-based, on-field assessment methods designed to identify potential lower extremity performance deficits and related impairments in this population. METHODS Eighteen patients (mean ± SD age, 16.9 ± 2.1 years; height, 170.0 ± 8.7 cm; body mass, 71.9 ± 21.8 kg) who returned to their sport within a year following ACL reconstruction (95% CI: 7.8 to 11.9 months from surgery) participated (ACLR group). These individuals were asked to bring 1 or 2 teammates to serve as control participants, who were matched for sex, sport, and age (n = 20; mean ± SD age, 16.9 ± 1.1 years; height, 169.7 ± 8.4 cm; body mass, 70.1 ± 20.7 kg). Functional performance was tested using the broad jump, vertical jump, modified long shuttle, modified pro shuttle, modified agility T-test, timed hop, triple hop, single hop, and crossover hop tests. A 1-way multivariate analysis of variance (MANOVA) was used to evaluate group differences for dependent performance variables. RESULTS The functional performance measurements of skills requiring bilateral involvement of both lower extremities showed no group differences between the ACLR and control groups (P>.05). An overall group difference (P = .006) was observed for the combined limb symmetry index (LSI) measures. However, the modified double-limb performance tasks (long shuttle, modified agility T-test, and pro shuttle) were not, independently, sufficiently sensitive to detect limb deficits in individuals with ACL reconstruction. Conversely, the LSI on the distance measures of the single-limb performance tasks all provided moderate to large effect sizes to differentiate between the ACLR and control groups, as the individuals who had ACL reconstruction demonstrated involved limb deficits on all measures (P<.05). Finally, the LSI for the timed hop test was not different between groups (P>.05). CONCLUSIONS These findings indicate that, while unilateral deficits are present in individuals following ACL reconstruction, they may not be evident during bipedal performance or during modified versions of double-limb performance activities. Isolation of the involved limb with unilateral hopping tasks should be used to identify deficits in performance.

The Relationship Between Pre-Operative and Twelve-Week Post-Operative Y-Balance and Quadriceps Strength in Athletes With an Anterior Cruciate Ligament Tear

“…This test not only measures neuromuscular control but has also been correlated to quadriceps and hip strength. 9,10 Particularly the anterior reach portion demonstrates high activation of the vastus medialis and lateralis. 11 The YBT-LQ has not been studied preoperatively in an ACL-R population to date.…”

“…The Y-Balance Test -Lower Quarter (YBT-LQ) is one of the functional tools used to measure single limb performance and neuromuscular control and has been studied in individuals with ACL-R. 9,10 The YBT-LQ requires an individual to load on a single leg and squat while reaching with the contralateral limb. This test not only measures neuromuscular control but has also been correlated to quadriceps and hip strength.…”

Reproducibility of Dynamic Body Balance Measurement by Center of Foot Pressure Analysis Immediately after Single-Leg Hop Landing

“…Furthermore, while the motor task used to measure dynamic balance is important, the measurement should be performed safely without engendering any feeling of fear. While the vertical drop jump and single-leg hop are often performed in clinical evaluation after ACL reconstruction surgery [9,10], this method affords a high risk for patients with no sports experience and those in the early phase after surgery on the knee joint. Thus, it would be useful to identify a motor task that can be safely performed by a wider range of subjects.…”

Did the NFL Lockout Expose the Achilles Heel of Competitive Sports?

“…We have shown that there are measurable functional deficits in athletes following surgical anterior cruciate ligament reconstructions after return to sport that are sustained up to 11 months after surgery. 13 While athletes may be prepared to begin sports-specific training for practice and competition, they typically demonstrate lingering deficits, that are not self-perceived and limit their potential for safe integration into full competition. Time will tell if there is an increase in reinjury occurrences in NFL athletes who sustained an injury in the past but were not fully rehabilitated during the Lockout.…”