by Christopher Pettit
Advancements in surgery and rehabilitation mean that anterior cruciate ligament (ACL) injuries and ruptures no longer mean the end of active sports participation. If there is no associated damage to the collateral ligaments, meniscus or degenerative changes within the knee, it may even be possible to manage the condition conservatively. This will be managed on a case-by-case basis depending on lifestyle, age and severity of damage.
Several factors are taken into account when we develop the rehabilitation program following surgery:
- The type of graft, the graft strength, healing time frames and the maturation of the graft.
- The effects of particular exercise on the graft.
- The role of certain muscles in limiting the stress on the ACL graft.
- Proprioception (improving the body’s awareness of where the knee is in space).
Following surgery the goal of rehabilitation is to:
- Reduce swelling and pain management as soon as possible. Swelling is addressed by following a regular RICE (Rest, Ice, Compression, Elevation) protocol; we find these supports to be very effective in the early stages following the injury and post-surgery.
- Restoration of ROM, during physiotherapy sessions, using manual mobilisation techniques and gentle mobilisation exercises.
- Increase active stability of the knee (improve muscle performance), without compromising the graft.
- Improve proprioception (reasons why explained further down).
- Graded return to whole body activities.
- Sport/lifestyle specific training.
Types of Exercise
Closed chain exercise, exercises where the foot is in contact with a non-moveable object, such as squatting are believed to minimise the stresses placed on the ACL, because they decrease the sheer forces through increased joint compression and muscular contraction.
Open chain exercises, exercises where the foot is in contact with a moving object, i.e. kicking a football, increase the sheer forces through the knee and although valuable later in rehabilitation, they are best avoided until deemed safe by your physiotherapist.
Important Factors in Helping the New ACL
Proprioception/hamstring firing timing: A healthy knee has a protective reflex with the ACL mechanoreceptors (small cells within the ligament what monitor movement) signalling excessive strain and triggering a reflex contraction of the hamstrings.
Sadly, damaging the ACL disrupts this reflex arc and lots of time will need to be dedicated to help compensate for this change. At Broadgate, we use a mini EMG device to give our patients visual feedback to help enhance the recovery of this protective co-contraction during functional activities.
Gluteus medius: An important muscle, which helps the thigh bone maintain a neutral position during movement. This decreases the rotational forces onto the knee/ACL, so it is important to generate co-contraction of this as well as the hamstrings during rehabilitation.
And finally, control of excessive foot pronation (if present): During CKC exercises and then functional activities, it is important to train in a neutral foot position and have the appropriate footwear to help maintain this when exercising.
Weeks 1-2: Work on range of motion, focus on gaining full extension, walking re-education, cycling.
Weeks 3-6: Closed-chain strengthening exercises, continued promotion of full range of motion.
Weeks 7-12: Beginning sport specific training, jogging, cycling outdoors, remaining with straight line activities, gradually progressing to shuttle runs, lateral movements and light pivoting.
Months 4-7: Constructed exercises must be adhered to not to undo all the good work. During this stage, plyometric work can begin.
Remember that everyone is different, so it is important to get assessed and check your progress at each landmark before progressing.
Find out more about the author Christopher Pettit, who is a qualified Exercise and Sports Scientist and Physiotherapist, at http://www.broadgatespinecentre.co.uk/london-physiotherapy/.