At a glance
Main symptoms
- A "pop" felt or heard at the moment of injury
- Marked knee swelling within the first hours
- The knee giving way or feeling unstable, especially when turning
- Hospital stay
- Usually one night in hospital.
- Recovery time
- 6–9 months
- Return to work
- Desk work usually after 1–2 weeks, standing jobs after 6–8 weeks, heavy physical work after 3–4 months.
The anterior cruciate ligament (ACL) runs through the middle of the knee, connecting the thigh bone to the shin bone, and is the main ligament that stops the shin sliding forward and controls rotation. It usually tears in sports such as football, basketball and skiing, during a sudden stop, change of direction or awkward landing. Meniscus or cartilage injuries often come with it.
Symptoms
Typical complaints:
- A "pop" felt or heard at the moment of injury
- Marked knee swelling within the first hours
- The knee giving way or feeling unstable, especially when turning
- Pain and limited movement
- Being unable to continue playing sport
Diagnostic Methods
The examination uses the Lachman test, the anterior drawer test and the pivot shift test to assess the ligament. MRI shows the tear and any meniscus, cartilage or other ligament injuries. X-rays are taken to check for a fracture.
Treatment Approach
Non-Surgical Treatments
For people who do not play pivoting sports, with a lower activity level, and for some partial tears, structured physiotherapy with muscle strengthening, balance work and activity modification can be used. If the knee stays unstable or keeps giving way, surgery is considered.
Surgical Treatment
A torn ACL usually does not heal when stitched, so an arthroscopic ACL reconstruction is performed. A graft prepared from the patient's own tendon (hamstring, patellar or quadriceps tendon) is placed in tunnels drilled in the bone to form a new ligament. Meniscus tears found at the same time can be repaired in the same operation.
Surgical Process
Performed under spinal or general anaesthesia through small incisions with a camera, usually taking 1–2 hours. Letting the swelling settle and regaining knee movement before surgery makes recovery easier.
Hospital Stay
Usually one night in hospital.
Recovery Process
- Weeks 0–2: Crutches, ice, regaining a straight knee and muscle control
- Weeks 2–6: Walking without support, increasing range of motion, physiotherapy
- Weeks 6–12: Strengthening, cycling, balance work
- Months 3–6: Starting to run under a physiotherapist's guidance, sport-specific exercises
- Around month 9: Return to pivoting sports after muscle strength and function tests
Return to Work
Desk work usually after 1–2 weeks, standing jobs after 6–8 weeks, heavy physical work after 3–4 months.
Potential Complications
Possible problems: knee stiffness and limited movement, pain at the front of the knee, tenderness where the graft was taken, deep vein thrombosis, infection (rare) and re-tear of the graft. Following the rehabilitation programme is the most important way to reduce these risks.
Frequently asked questions
What happens if I don't have surgery?
Some people manage daily life well with physiotherapy. In pivoting sports, however, the knee can keep giving way, which over time increases the risk of meniscus and cartilage damage.
When can I return to sport?
Return to pivoting and jumping sports is usually advised around month 9, once muscle strength and function tests are good enough. Returning early increases the risk of a re-tear.
Which graft is used?
Hamstring, patellar and quadriceps tendons are the common options. The choice depends on age, sport and the state of the knee, and is made together at the consultation.
This content is for information only and does not replace examination, diagnosis or treatment. The right treatment for you is decided after an examination.