What is ACL reconstruction?
The anterior cruciate ligament (ACL) is one of the two cruciate ligaments inside the knee. It is the primary restraint to forward movement of the shin bone relative to the thigh bone, and controls rotational stability — which is why ACL injuries are so disabling for sportspeople.
In many cases, the ACL cannot heal itself when torn. Reconstruction replaces it with a tendon graft — usually taken from your own hamstring or patellar tendon — which is threaded through tunnels drilled in the femur and tibia and fixed in position. Over 9–12 months, the graft matures and becomes a functional ACL substitute.
Not everyone with an ACL tear requires surgery. Some patients — particularly older, less active individuals — do well with physiotherapy and activity modification. Dr Mooney will discuss your options honestly at your consultation.
What happens during surgery
ACL reconstruction is performed arthroscopically — through small keyhole incisions — under general anaesthesia. Dr Mooney first assesses the knee thoroughly, addressing any associated meniscal or cartilage pathology at the same time.
The graft is harvested (typically hamstring tendons or patellar tendon), prepared, and passed through tunnels drilled in the femur and tibia. The graft is tensioned and fixed at each end. The operation typically takes 60–90 minutes.
ACL with LET (Lateral Extra-articular Tenodesis)
Lateral Extra-articular Tenodesis (LET) is an additional procedure sometimes performed at the same time as ACL reconstruction. It provides an extra restraint to rotational instability, addressing residual rotational laxity that can persist even after a technically successful ACL reconstruction.
LET is most commonly recommended for younger patients returning to high-level pivoting sport, those with high-grade rotational instability, generalised ligamentous laxity, or revision ACL surgery. Published evidence — including the STABILITY trial — has shown that adding LET significantly reduces the re-tear rate in high-risk patients.
“For my younger, active patients with significant rotational instability, I routinely discuss LET as part of the ACL reconstruction. The evidence is clear that it reduces the risk of re-tear in high-risk groups, and re-tearing an ACL graft is something we very much want to avoid.”
— Dr Luke Mooney
What to expect after surgery
Week 1–2Crutches and brace. Range of movement exercises starting.
Week 2–6Progressive weight bearing. Brace weaned. Physiotherapy for swelling and quadriceps activation.
6 weeksWalking normally. Stationary cycling. Return to light manual work.
3 monthsJogging programme beginning. Agility and proprioception training.
6 monthsReturn to non-contact training. Strength testing. Graft maturation continuing.
9–12 monthsReturn to full competition for most patients, once strength and functional testing criteria are met.
