Knee Problems: ACL Reconstruction

Introduction

	Arthroscopic view of torn anterior cruciate ligament

Anterior cruciate ligament surgery and rehabilitation have undergone dramatic changes over the past decade, due to extensive clinical experience, improved surgical technique and better understanding of rehabilitation. Pre and post-operative rehabilitation is a major factor in the success of ACL reconstruction. Early restoration of full joint movement and weight-bearing are of paramount importance for successful rehabilitation. We aim to ensure a complete understanding of the basic principles of the ACL reconstruction, to restore the full range of motion, near normal strength and to mentally prepare the patient for the operation and accelerated rehabilitation. The major goals of ACL surgery and rehabilitation are: to restore normal joint anatomy, to provide static and dynamic knee stability and return to work and sport as soon as possible. It is very important that the patient takes an active part in the rehabilitation, both before and after the operation. Our goal is to guide our patients through the rehabilitation without unnecessary restrictions.

About the ACL

The knee is a complex joint, which has the ability to bend and rotate slightly. Knee ligaments help control motion by connecting bones and bracing the joint against abnormal types of motion.

The ACL links the back of the femur (thighbone) to the centre of tibia (shinbone), stabilising the knee, mainly in the forwards and backwards direction. In addition to its mechanical restraining function, the ACL provides important neurological feedback that directly affects perception of joint position, and reflex muscular stabilisation of the joint or proprioception. Conscious and subconscious proprioception is essential for normal joint function in daily activities, occupational tasks and sports. Proprioception diminishes following capsulo-ligamentous injury, but is significantly restored following surgical ACL reconstruction and rehabilitation. A typical mechanism of an ACL injury is a non-contact twisting movement, usually due to abrupt deceleration and change of direction. Side-stepping (cutting), pivoting and landing from a jump are examples of events that may cause an ACL tear. An audible pop or crack, pain and the knee giving way are typical initial signs, followed by almost immediate swelling, due to bleeding inside the joint.

Associated damage to other important joint structures, such as collateral ligaments, menisci, and articular cartilage is very frequent. Some patients achieve satisfactory stability and function with non-operative treatment (rehabilitation and adjustments to daily activities and sports). However, chronic ACL deficiency results in gradual damage to the menisci and articular cartilage and consequent early joint degeneration.

ACL Reconstruction

	ACL reconstruction with patella tendon autograft.

ACL reconstruction is not an emergency operation. Delaying surgery until a full range of motion is obtained significantly reduces the chance of having problems post-operatively.

Delaying acute surgery also allows the patient to be mentally better prepared for surgery and gives the patient time to learn, fully understand and practise adequate exercises.

A complete tear of the ACL has minimal ability to heal and often requires surgical reconstruction. This involves replacing the torn ligament, usually with the middle third of the patella tendon (bone-patella tendon-bone autograft).

Fastening the graft to the bone with interference screws provides secure fixation which enables early accelerated progressive rehabilitation to take place. Surgery is followed by 1 to 2 days of hospital stay and by several months of intensive rehabilitation to restore normal range of motion, strength, flexibility and proprioception.

Pre-Operative Rehabilitation

Pre-operative rehabilitation is extremely important for the successful outcome of ACL reconstruction.

Patients with an ACL deficiency, suitable for reconstructive surgery, are educated on the nature of their problem, surgical technique and peri-operative rehabilitation, by the surgeon, at the time of the first clinic visit. They are also visited by the physiotherapist, prior to the operation, and guided through an updated rehabilitation programme.

Regaining a full range of motion, strength and proprioception before and the operation, especially full symmetrical hyperextension, minimises post-operative problems.

Perioperative ACL Rehabilitation

For an update on perioprative ACL rehabilitation please see our separate page on Accelerated ACL Reconstruction Rehabilitation Program which was kindly written and put together by Mark De Carlo and his team at the Methodist Sports Medicine Center, Indianapolis, Indiana, USA.

Further Information:
"A Perioperative Rehabilitation Program for Anterior Cruciate Ligament Surgery" Todd Arnold, MD, K. Donald Shelbourne, MD: The physician and sportsmedicine, Vol 28 - No. 1 - January 2000

Downloads:
Chester Knee Clinic Guide to Accelerated Rehabilitation of ACL Reconstructed Knees

Site last updated on: 20 June 2008

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