Functional Performance Testing After Anterior Cruciate Ligament Reconstruction

Abstract

Background:When to allow an athlete to return to unrestricted sporting activity after anterior cruciate ligament (ACL) reconstruction remains controversial.Purpose:To report the results of functional performance testing reported in the literature for individuals at differing time points following ACL reconstruction and to examine differences between graft types.Study Design:Systematic review; Level of evidence, 4.Methods:A systematic review of Medline, Scopus, and Cochrane Central Register of Controlled Trials was performed using PRISMA guidelines. Inclusion criteria were English-language studies that examined any functional rehabilitation test from 6 months to 2 years following ACL reconstruction. All patient-, limb-, and knee-specific demographics were extracted from included investigations. All functional rehabilitation tests were analyzed and compared when applicable.Results:The search term returned a total of 890 potential studies, with 88 meeting inclusion and exclusion criteria. A total of 4927 patients were included, of which 66% were male. The mean patient age was 26.5 ± 3.4 years. The predominant graft choices for reconstruction were bone–patellar tendon–bone (BPTB) autograft (59.8%) and hamstring autograft (37.9%). The most commonly reported functional tests were the hop tests. The results of these functional tests, as reported in the Limb Symmetry Index (LSI), improved with increasing time, with nearly all results greater than 90% at 1 year following primary ACL reconstruction. At 6 months postoperatively, a number of isokinetic strength measurements failed to reach 80% LSI, most commonly isokinetic knee extension testing in both BPTB and hamstring autograft groups. The knee flexion strength deficit was significantly less in the BPTB autograft group as compared with those having hamstring autograft at 1 year postoperatively, while no significant differences were found in isokinetic extension strength between the 2 groups.Conclusion:Hop testing was the most commonly reported functional test following ACL reconstruction. Increases in performance on functional tests were predictably seen as time increased following surgery. Those with hamstring autografts may experience increased strength deficits with knee flexion versus those having BPTB autograft. These data provide information that may assist providers in determining timing of return to unrestricted sporting activity.

Isokinetic muscle strength and readiness to return to sport following anterior cruciate ligament reconstruction: is there an association? A systematic review and a protocol recommendation

“…Angular velocity influences both the torque and work output, and as such, should be considered when assessing strength and using it as part of the RTS criteria 30 40 56 59. The two most common angular velocities reported were 60°/s and 180°/s in 29 (74%) and 18 (46%) studies, respectively.…”

“…The studies reported a desirable limb symmetry index that ranged from ≥70% to 90%. However, many studies report an increase in limb symmetry index with higher angular velocities 7 29 30 45 59. This could mean that in some studies the RTS criterion was met more easily than in others.…”

Young Athletes After Anterior Cruciate Ligament Reconstruction Cleared for Sports Participation: How Many Actually Meet Recommended Return-to-Sport Criteria Cutoffs?

“…10 Among the studies that reported use of objective criteria for return-to-sport decision making, the most commonly used assessments were strength testing, performance-based functional testing, and self-reported knee function; although specific criterion values varied widely among studies. 10,23 Strength tests of the quadriceps and hamstrings 10,11,[15][16][17][18]26,41,47,59,60 and the single-leg hop test 1,10,25 are among the most commonly used to objectively determine patient readiness for return to sports after ACL reconstruction and are associated with several indicators of return-to-sport success. Typically, limb symmetry indices (LSIs) are used to assess whether muscle strength and functional performance are restored after ACL reconstruction compared to the uninvolved limb.…”

Biomechanical Adaptations After Fatiguing Exercise in Healthy and ACL Reconstructed Individuals

“…This supports rehab progression from strengthening to functional tests before returning to activity, however the most commonly used functional test before release to activity is the single leg hop for distance. 1 The single hop for distance was only correlated with peak vertical ground reaction forces, however was not retained in the model and was not correlated with any changes in gait after exercise.…”

“…115 Other protocols utilize a combination of anaerobic exercises, such as squat jumps and short sprints, 39,123 or single leg landings and squats 41 to induce fatigue using exercises that simulate movements experienced during sport and activity. Graded treadmill exercise has been used previously to test cardiopulmonary fitness, 1,204 however has been used for knee rehabilitation because it increases quadriceps activation 110 and is a popular choice to induce neuromuscular fatigue. 38,44,103 These types of aerobic protocols are not applicable to sporting environments that require both high-intensity aerobic and anaerobic components.…”