ANTERIOR CRUCIATE LIGAMENT TEAR
||Partial or complete rupture of the Anterior
and X-ray of a Normal Knee
||Located in the center of the knee, the
ACL is a strong band of tissue that prevents the shin bone (tibia)
from extending excessively beyond the thigh bone (femur). ACL
injuries are common and usually sports-related—especially
associated with basketball, football and skiing.
The four primary stabilizers of the knee are the ACL, the PCL
(Posterior Cruciate Ligament), the MCL (Medial Collateral Ligament)
and the LCL (Lateral Collateral Ligament). These ligaments function
in concert with the muscles and cartilage of the knee to help
control motion. Proprioceptive (nerve) fibers in these ligaments and
the capsule of the knee joint augment this control via reflex
Picture of Normal and Torn ACL
||An ACL injury may result from a violent,
twisting motion (deceleration, valgus, rotation) of the knee, which
can occur when an athlete plants his or her foot and suddenly
changes direction. The ACL can also tear if the knee is 'hyperextended'
Almost any sport that involves jumping, cutting or twisting has an
inherent risk of an ACL rupture. Basketball, skiing, soccer and
football are among the most common sports associated with this
||Patients with ACL tears usually describe
a twisting or hyperextension of the knee. The patient may also feel
a "popping" in the knee that is associated with immediate
swelling. Typically, there is a significant effusion
(excess fluid inside the knee) when the patient is first
evaluated. A complete examination of the knee should be done to rule
out associated injuries such as a fracture or a meniscus tear. The
Lachman test is the best way to assess a knee for an acute ACL
rupture. Range of motion should also be documented. Usually, the
patient has difficulty fully straightening the knee immediately
after the injury. This may be due to swelling or entrapment of the
ACL stump in the intracondylar notch. Occasionally, a displaced
bucket handle tear of the meniscus or a sprain of the medial
collateral may present in conjunction with an ACL tear and lead to
frank locking of the knee.
of Normal and Torn ACL
||ACL tears must be treated on a individual
patient basis. Some patients with limited physical goals do very
well with nonoperative treatment. Most patients, however, that wish
to participate in cutting and twisting type sports should strongly
consider ACL reconstruction to prevent further damage to the knee.
Nonoperative: Nonoperative treatment is indicated for
patients with limited activity goals or with partial ACL
tears. Initially, icing and an anti-inflammatory medication are
recommended to control pain and swelling. Draining the knee may
accelerate the recovery time. After the pain and swelling subside a
program should be prescribed to increase knee range of motion and to
strengthen the quadriceps and hamstrings muscles. Sport-specific
drills in the later treatment stages help restore balance and
coordination. Finally, using a brace when resuming sports-related
activities may be helpful.
Operative: Operative treatment is indicated for patients who
have giving way of the knee during activities of daily living or for
patients who wish to return to cutting and twisting type sports. The
combination of less invasive surgical techniques and more aggressive
rehabilitation have made ACL reconstruction much better in the last
few years. Many methods exists for reconstructing the ligament and
are highly dependent upon the surgeon's training and experience.
The three most common ways to reconstruct the ligament are with a
bone-patellar tendon-bone autograft, a hamstring autograft, or with
some form of allograft tissue (patellar tendon and achilles tendon
are the most popular). Screws or other devices are then used to
secure the graft in position inside the knee. Allografts--which
involve using tissue from cadavers--are a viable, and increasingly
popular, graft option.
After the surgery, rehabilitation is begun within a few days.
Restoring full knee range of motion is the initial goal. Strength,
endurance and coordination drills are added as the patient improves.
Typically, the patient may return to activities of daily living with
a 1-3 weeks and progress to full sporting activity in 6 months
depending upon the surgeon's preference and the patient's recovery.
Many important choices must be made when having ACL surgery. A
consultation with a surgeon of your choice should help clarify the
Surgery: Incisions and Autograft Preparation
SURGERY MODULE (NEW!)
Maintaining excellent flexibility, strength and endurance of the
quadriceps and hamstring muscles may prevent some ACL tears. It has
been demonstrated that watching ski injury prevention videos reduces
the incidence of ski related ACL tears. A review of the recent
literature, however, reveals a dearth of articles related to ACL
tear prevention. Clearly, more research is needed in this area.