Traumatic dislocation of the
knee was once defined as the complete loss of the tibiofemoral articulation.
More recently, this definition has been expanded to include bicruciate
injuries of the knee and any knee injury that includes 3 or more major
ligaments. The incidence of these injuries is rising due to several factors,
including the expanded definition, an improved awareness of multiligament
knee injuries, and the increase in the number of people participating
in high speed, risk-taking sports. However, it is still estimated that
the average orthopedic surgeon will only treat three or four of these
injuries during their entire career.
Management of the dislocated
knee begins with a careful physical and radiological examination. Associated
injuries such as fractures and arterial lesions are common and need to
be excluded. Currently, there is controversy in the orthopedic literature
regarding whether or not an arteriogram is a necessary part of this evaluation.
There is consensus, however, that the early management of the multi-ligament
knee injury includes prompt reduction and immobilization of the knee joint
with frequent reassessment to ensure maintenance of reduction and adequate
limb perfusion. Surgery in the acute setting is generally limited to those
injuries that cannot be kept in a reduced position or when a fracture
or arterial injury is present.
Definitive treatment of the
dislocated knee has evolved over the last 30 years as knowledge of these
injuries has increased and less-invasive operative techniques have been
refined. Currently, nonoperative treatment is generally limited to older
or inactive patients or those with other serious injuries such as traumatic
brain injury. Surgical repair or reconstruction of all major ligaments
injured is the mainstay of treatment for most patient. Magnetic resonance
imaging (MRI) is a valuable tool for assessing the extent of injury and
for planning the reconstructive procedure. Surgery may be performed within
two weeks of the knee injury or delayed several weeks until motion in
the joint is restored, depending on which knee structures are injured.
Rehabilitation after
the treatment of the multi-ligament knee injury is a lengthy process regardless
of whether or not surgery is performed. The specific protocol depends
on several factors, such as the presence or absence of associated injuries,
the number and type of ligaments disrupted and the integrity of the repair
or reconstruction. However, prevention of scar tissue and knee stiffness
with range of motion exercises is an important part of any therapy program.
Due to the severe nature of the initial knee injury, it may take up to
one year to regain full motion of the knee and to resume athletic participation.
The outcome after surgical treatment is good or excellent in most patients;
however, limitations in activity are not uncommon.