PulseExploreJournal ClubDebatesTrendingResearchersJournals
Instagram
HomeExploreJournal ClubTrending
Synapse
⌘+K
Synapse
February 19, 2026Knee Surgery Sports Traumatology Arthroscopy1 citationsOpen Access

Impact of hamstring versus quadriceps tendon graft on thigh muscle strength and surface electromyography activity after anterior cruciate ligament reconstruction

View Full Paper
BFBenjamin ForquignonTDTobias DrenckMKM. Krause

Key Points

  • This research aims to compare the effects of hamstring and quadriceps tendon grafts on muscle strength and activity after ACL reconstruction.
  • Evaluated sixty patients at a mean follow-up of 24 months post-surgery.
  • Measured maximum isometric strength of knee flexors and extensors, normalized to body weight.
  • Analyzed muscle activity using surface electromyography (sEMG), normalized to maximum voluntary contraction.
  • Conducted clinical assessments using various stability tests and patient-reported outcome measures.
  • No significant differences in limb symmetry index between the hamstring and quadriceps groups.
  • Hamstring group exhibited reduced flexion strength; quadriceps group had reduced extension strength.
  • Lower bodyweight-normalized flexion strength in the hamstring group compared to quadriceps group.
  • No significant differences in sEMG activity between types of grafts or limb sides.
  • No differences in clinical stability or patient-reported outcomes were noted.

Abstract

Abstract Purpose To compare quadriceps tendon (QT) and hamstring tendon (HT) autografts regarding isometric thigh muscle strength, surface electromyography (sEMG) activity and clinical outcomes following anterior cruciate ligament reconstruction (ACLR). Methods Sixty patients (HT: n = 36; QT: n = 24) were evaluated at a mean follow‐up of 24 months. Maximum isometric strength of knee flexors and extensors was measured and normalised to body weight. Muscle activity of the quadriceps and hamstrings was evaluated using sEMG and normalised to maximum voluntary contraction (MVC). Clinical assessments included the Lachman, Pivot‐Shift and Rolimeter tests, as well as patient‐reported outcome measures (International Knee Documentation Committee, Lysholm, Tegner activity scale). Results Limb symmetry index (LSI) values did not differ significantly between the HT and QT group. Within‐group analysis showed reduced flexion strength in the HT group ( p < 0.001) and reduced extension strength in the QT group ( p = 0.045). The HT group demonstrated significantly lower bodyweight‐normalised flexion strength compared to the QT group ( p = 0.034), with no difference in extension strength ( p = 0.184). No significant differences were observed in sEMG activity between graft types or limb sides. Clinical stability and patient‐reported outcomes did not differ between groups. Conclusion Both grafts provide excellent clinical outcomes. No statistically significant differences in muscle activation were detected at midterm follow‐up, yet equivalence should not be inferred from this finding. This is one of the first studies to include sEMG analysis during maximum isometric contractions when comparing QT and HT grafts. Persistent graft‐specific weaknesses, quadriceps after QT and hamstrings after HT, highlight the need for targeted rehabilitation focusing on the affected muscle group to address these imbalances. Level of Evidence Level III.

Ask AI
Helpful
Bookmark
Share
View Full Paper

Cite This Study

Forquignon et al. (2026) studied this question.

synapsesocial.com/papers/6996a7c3ecb39a600b3edc9dhttps://doi.org/10.1002/ksa.70342
Ask AI
Helpful
Bookmark
Share
View Full Paper