ACL Reconstructed Patients Have Persistent Hip Strength and Functional Deficits After Return-to-

Play

Jeremy M. Burnham MD1, Michael C. Yonz MD1, Darren L. Johnson MD1, Mary Lloyd Ireland MD1, and Brian Noehren PhD2

1Department of Orthopaedic Surgery and Sports Medicine, College of Medicine, University of Kentucky2Division of Physical Therapy, BioMotion Laboratory, College of Health Sciences, University of Kentucky

Disclosures

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Introduction

• Current return-to-play (RTP) guidelines after ACL reconstruction (ACLR) are controversial

• Readiness for return to sports is usually based on a combination of factors, including surgeon preference, physical therapist assessment, functional tests, and time from surgery.

• Recent studies have suggested that ACLR patients may have persistent functional deficits even after returning to competitive sports.

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Introduction

• The purpose of this study was to investigate the lower extremity strength and functional test performance of ACLR patients who had been cleared to return to sports.

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Methods

• 20 consecutive autograft ACLR patients cleared for RTP by surgeon and therapist, 20 matched controls

• Strength tests: isometric hip external rotation, hip extension, hip abduction, and knee extension

• Single leg step-down test (60 seconds)

• Hop tests: single leg, timed, crossover, and triple hop

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Methods

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A C

Demonstration of (A) hip external rotation (B) hip abduction, (C) hip extension, and (D) step-down tests.

A

C

DB

Results

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  No. Age (yrs) Sex BMI Follow-up (months) Graft Type Tegner

ACLR 20 22.85 (15-45)

11 female, 9 male

23.68 (SD=2.83) 8.3 (6-14) 5 HAM-AUTO, 12

BPTB, 3 HAM-AUG 5.75 (SD=1.73)

Control 20 25.45 (21-38)

11 female, 9 male

24.24 (SD=3.41) -- -- 5.75 (SD=0.97)

-- Not Applicable; BPTB: Bone Patellar Tendon Bone; HAM-AUTO:: Hamstring Autograft; HAM-AUG: Hamstring Autograft Augmented with Hamstring Allograft

Results

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*

** *

*

**

SLSD

Results

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  ACLR CONTROLS

Tests Mean Mean Difference (vs. ACLR) P-value

Hip Extension 19.92 7.22 22.19 8.94 2.46 0.390

Hip External Rotation 10.29 3.52 12.91 4.34 2.62 0.043*

Hip Abduction 29.35 5.75 29.92 9.76 0.57 0.823

Knee Extension 31.41 12.23 38.24 17.19 6.84 0.155

SLSD (Repetitions in 60s) 31.8 11.57 40.05 10.93 8.25 0.026*

Single Leg Hop (cm) 132.11 36.67 168.01 34.60 35.90 0.003*

Timed Hop (seconds) 3.33 1.99 2.19 0.50 -1.14 0.017*

Triple Hop (cm) 378.85 105.38 476.26 100.58 97.41 0.005*

Crossover Hop (cm) 330.68 106.63 417.81 107.04 83.83 0.015*

* Statistically significant, ** Trend, Standard deviation, Statistically significant differences in bold; SLSD = Single Leg Step-Down Test 

Discussion & Conclusions

• At a mean follow-up time of >8 months, ACLR patients who had been cleared to RTP exhibited deficiencies in hip external rotation strength, SLSD performance, and hop test performance as compared to a matched control group.

• The worse performance of ACLR subjects on the SLSD test but not KEXT strength test indicate that some ACLR subjects deemed ready for sports may continue to lack the power and endurance needed for successful sports participation.

• These results suggest that more objective measures should be used when evaluating patients’ return to play readiness.

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