Variability in leg muscle power and hop performance after anterior cruciate ligament reconstruction
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The purpose of this prospective study was to describe the variability in leg muscle power and hop performance up to 2 years among patients following ACL reconstruction and specifically to illustrate the effects of various criteria for an acceptable level of muscle function.
Eighty-two patients (56 men and 26 women) with a mean age of 28 years, who underwent ACL reconstruction using either hamstring tendons (n = 46) or a patellar tendon (n = 36), were assessed pre-operatively and 3, 6, 12 and 24 months post-surgery with a battery of three lower extremity muscle power tests and a battery of three hop tests.
Leg symmetry index (LSI) values at group level ranged between 73 and 100% at all follow-ups. When the tests were evaluated individually, patients reached an average LSI of ≥90% at 24 months. The success rate at 24 months for the muscle power test battery, that is, patients with an LSI of ≥90% in all three tests, was 48 and 44% for the hop test battery. The success rate at 24 months for both test batteries on all six muscle function tests was 22%. The criterion of an LSI of ≥80% resulted in 53% of the patients having an acceptable level on all six tests, while with a criterion of an LSI of ≥100%, none of the patients reached an acceptable level.
At group level and in single muscle function tests, the muscle function outcome 1 and 2 years after ACL reconstruction is satisfactory in the present study and on a par with the results presented in the literature. However, when using more demanding criteria for a successful muscle function outcome, using batteries of tests or increasing the acceptable LSI level from ≥90% to ≥95% or ≥100%, the results are considered to be poor. It is suggested that this should be taken into consideration when presenting results after ACL rehabilitation, deciding on the criteria for a safe return to sports, or designing rehabilitation programmes after ACL reconstruction.
Level of evidence
Prognostic prospective cohort study, Level I.
KeywordsStrength tests Muscle function Rehabilitation Criteria Return to sports
This study was supported by a grant from the Swedish Centre for Research in Sports and the Local Research and Development Council for Gothenburg and Southern Bohuslän, Sweden. The authors declare that the experiments comply with current Swedish legislation.
- 1.Ageberg E, Roos HP, Silbernagel KG, Thomee R, Roos EM (2009) Knee extension and flexion muscle power after anterior cruciate ligament reconstruction with patellar tendon graft or hamstring tendons graft: a cross-sectional comparison 3 years post surgery. Knee Surg Sports Traumatol Arthrosc 17:162–169PubMedCrossRefGoogle Scholar
- 10.Foster TE, Wolfe BL, Ryan S, Silvestri L, Kaye EK (2010) Does the graft source really matter in the outcome of patients undergoing anterior cruciate ligament reconstruction? An evaluation of autograft versus allograft reconstruction results: a systematic review. Am J Sports Med 38:189–199PubMedCrossRefGoogle Scholar
- 19.Keays SL, Bullock-Saxton JE, Keays AC, Newcombe PA, Bullock MI (2007) A 6-year follow-up of the effect of graft site on strength, stability, range of motion, function, and joint degeneration after anterior cruciate ligament reconstruction: patellar tendon versus semitendinosus and Gracilis tendon graft. Am J Sports Med 35:729–739PubMedCrossRefGoogle Scholar
- 21.Linko E, Harilainen A, Malmivaara A, Seitsalo S (2005) Surgical versus conservative interventions for anterior cruciate ligament ruptures in adults. Cochrane Database Syst Rev, CD001356Google Scholar
- 45.Tegner Y, Lysholm J (1985) Rating systems in the evaluation of knee ligament injuries. Clin Orthop Relat Res, 43–49Google Scholar