Difference in Early Results Between Sub-Acute and Delayed ACL reconstruction: A Randomized Controlled Trial

Differences in Early Results Between Sub-Acute and Delayed ACL Reconstruction: A Randomized Controlled Trial

Henrik Illerström*, Björn Barenius*, Karl Eriksson*

 *Dep.of Orthopaedics, Institution for clinical studies and education, Södersjukhuset, Karolinska Institutet,11883 Stockholm

Disclosure

The authors have no financial conflicts to disclose

The Study at a glance

Background: Does acute ACL reconstruction lead to arthrofibrosis as we have been told?

Aim: Is it safe to do a sub-acute arthroscopic ACL reconstruction?

Method: Patients with acute ACL ruptures and Tegner > 6 were randomized between sub-acute and delayed reconstruction.

Results: 70 patients were included. 64 (91%) patients were assessed at three months and 67 (96%) at six months. At three months there were no differences between the groups in ROM neither in total ROM, extension or flexion. At six months there were signs of more functional strength in the acute group.

Conclusion: Arthroscopic ACL reconstruction is safe to perform in a sub-acute setting in an active population.

Introduction

Numerous reports of arthrofibrosis after early ACL reconstruction in the 90’s1 led to a paradigm shift and the acute surgery after knee injuries in the 30’s-50’s were abandoned and the principal most surgeons today would prefer was adopted:

No ACL reconstruction before ROM is normalised

But are the risks of acute surgery still valid with the arthroscopic surgery of today? There are indications that this is not true2. And are there any benefits for the patient with an early ACL reconstruction?

The aim of this study was to investigate if it is safe to reconstruct the ACL within the first week after the injury. And to observe if there are differences in outcome after ACL reconstruction depending on the time between injury and reconstruction and additional injuries.

MethodStudy design: A randomized controlled trial with primary endpoint ROM at 3

months. Randomization between sub-acute ACL reconstruction (within 8 days after the injury) and delayed ACL reconstruction (after normalized ROM, 6-10 weeks after the injury) According to the power analysis 64 patients was needed to find a difference of 5 degrees in ROM between the groups.

Inclusion criteria: Primary ACL injury in knee healthy person between 18-40 years of age with Tegner activity of at least 6 and a conviction of a need for an ACL reconstruction to continue their preferred activity level. No additional injuries on MRI indicating a need for an acute procedure.

Surgical method: One center, four surgeons, Arthroscopic ACL reconstruction with Endobutton® fixation in femur and metal interference screw in tibia. Single bundle quadrupled semitendinosus tendon graft, if < 65mm length gracilis tendon added to graft. Free periostal flap attached to graft at femur aperture.

Rehabilitation: One center, Full weight-bearing after surgery, open chain exercises allowed after 6 weeks, running after 14 weeks and return to sport if Biodex®3 showed > 90% strength of CL leg.

Results: Descriptives

Out of 2088 assessed patients, all with an acute knee injury assessed at our knee clinic, 70 patients were included according to our strict criteria. There were no significant differences of additional injuries or the need for adding the Gracilis tendon to the grafts between the groups. 70 % were males. One patient dropped out early from the delayed group. “Could not wait”. A second patient dropped out late due to inability to comply with rehab and study protocol.

Primary endpoint at 3 months

At 3 months, 64/70 (91% ) patients were assessed with a goniometer by a non blinded physiotherapist. The contralateral leg was used as reference. There were no significant difference in either extension, flexion or total ROM between groups.

Laxity 6 monthsMeasured with Rollimeter4 and Pivot shift test – At 6 months no significant difference were found between the groups.

Function 6 months

Activity 6 months

IKDC Objective Score5 for knee function. After 6 months a majority of patients scored A or B, with no significant difference between groups.

Before injury the Tegner activity level6 was median 8-9 a high recreational level, after 6 months the median patient had 4 correlating to running 2-3 times/w. No significant difference between groups were found.

Functional Strength at 6 months

Acute Delayed Sign.Thigh circumference 0.9 (1.0) 1.5 (1.2) 0.04(cm deficit vs CL)

One leg hop difference7

0.009 ≥90% 15 6 76-89% 11 10 50-75% 8 13 <50% 0 7

Biodex® Peak Torque deficit vs CL.Ext. isokinetic 60 deg/s 27 (15) 34 (18) NSFlex. isokinetic 60 deg/s 14 (13) 17 (16) NS

Compared to contralateral leg, the acute group had significantly less muscle atrophy of the thigh muscles and more patients in the acute group passed or were close to passing the one leg hop test. However there were no difference in strength between the groups in the Biodex® test.

As seen in the diagram below to the left, the patients were healthy according to KOOS8 before the injury. A drastic decrease in the KOOS was seen after the injury (diagram below to the right). The KOOS six months after the reconstruction (diagram to the right) show a major increase in the health related quality of life compared to before the surgery, but with major differences compared to pre-injury. In all diagrams red lines for the acute group and blue for the delayed, there were no significant difference between groups.

KOOS

How is your knee working? Weekly SMS survey for the first 3 months after the reconstruction.

The diagram below show the mean results from the SMS-survey, red lines for the acute group and blue for the delayed. The error bars indicate one standard deviation. Ten was defined as no knee function and 0 normal function. There was no significant difference between the groups at any time-point.

Discussion

• The results of this study suggest that there is not an increased risk for arthrofibrosis after an acute ACL-reconstruction.

• For patients with high functional demands, the results suggest that it is a possible to preserve muscular and functional strength with an acute ACL-reconstruction, thus speeding up the rehab process and decrease the time before the return to a desired activity level.

• The results of this study suggests that the time spent on rehab before the reconstruction is not as useful as the rehab after the surgery. With an acute reconstruction the time between injury and recovery after the reconstruction can be minimized.

Take Home Message!

If the patient and you have decided an ACL reconstruction is indicated

then there is no reason to waitReferences:1. Shelbourne KD, Wilckens JH, Mollabashy A, DeCarlo M. Arthrofibrosis in acute anterior cruciate ligament reconstruction. The effect of timing of reconstruction and rehabilitation. Am J Sports Med. 1991;19(4):332-336.2. Bottoni CR, Liddell TR, Trainor TJ, Freccero DM, Lindell KK. Postoperative range of motion following anterior cruciate ligament reconstruction using autograft hamstrings: a prospective, randomized clinical trial of early versus delayed reconstructions. Am J Sports Med. 2008;36(4):656-662.3. Taylor NA, Sanders RH, Howick EI, Stanley SN. Static and dynamic assessment of the Biodex dynamometer. European journal of applied physiology and occupational physiology. 1991;62(3):180-188.4. Balasch H, Schiller M, Friebel H, Hoffmann F. Evaluation of anterior knee joint instability with the Rolimeter. A test in comparison with manual assessment and measuring with the KT-1000 arthrometer. Knee Surg Sports Traumatol Arthrosc. 1999;7(4):204-208.5. Hefti F, Muller W, Jakob RP, Staubli HU. Evaluation of knee ligament injuries with the IKDC form. Knee Surg Sports Traumatol Arthrosc. 1993;1(3-4):226-234.6. Tegner Y, Lysholm J. Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res. 1985;198:43-49.7. Noyes F, Barber S, Mangine R. Abnormal lower limb symmetry determined by function hop tests after anterior cruciate ligament rupture. Am J Sports Med. 1991;19(5):513 - 518.8. Roos EM, Roos HP, Lohmander LS, Ekdahl C, Beynnon BD. Knee Injury and Osteoarthritis Outcome Score (KOOS)--development of a self-administered outcome measure. The Journal of orthopaedic and sports physical therapy. 1998;28(2):88-96.