The Knee and Patellofemoral Joints 289is believed to cause damage and arthritic changes to
the articular surface of the knee.
However, even if surgery is indicated, if the type
of injury allows, surgery is often performed through
a small scope (arthroscopic surgery) with an attempt
to preserve or repair whatever part of the meniscus is
viable or has sufficient blood supply to allow healing
(Quirk, 1987; Scioscia, Giffin, and Fu, 2001). Such
an approach allows for a shorter recovery period and
less risk of future degenerative arthritis than open
surgery involving full removal of the meniscus. The
stress to the loaded tibiofemoral joint has been esti-
mated to be three times higher when the meniscus
is removed (Hall, 1999).
Recovery from meniscal injury, even when surgery
is required, is generally excellent. Over the long
term, this type of injury holds a very good prognosis
for full return to dance.The Terrible TriadWith some injuries, multiple structures can be
involved. When a rotational component is added to
the medially directed force on the knee, the ACL
and medial meniscus, as well as the medial collat-
eral ligament, can be injured simultaneously. This
combination injury is termed the “terrible triad”
(G. trias, three). It is a serious injury that requires
prompt medical diagnosis and treatment.Extensor Mechanism InjuryAny component of the extensor mechanism—includ-
ing the quadriceps muscle itself, the tendons of the
quadriceps, and the patella—can be injured, but
the latter two are particularly commonly involved. A
description of several injuries involving these latter
two structures follows.Patellofemoral Pain Syndrome Patellofemoral pain
syndrome refers to anterior knee pain that relates
to the patella and associated retinacular support
as seen in figure 5.34A. In cases in which there is
documented damage to the thick cartilage that lines
the backside of the patella, patellofemoral pain can
be more specifically classified as chondromalacia
patella, which literally means soft (“malacia”) car-
tilage (“chondro”). Patellofemoral pain is the most
prevalent type of knee pain in adolescents and young
adults, and one of the most common complaints
bringing athletes to sports medicine clinics (Caillet,
1996; Garrick, 1989; Mercier, 1995; Weiker, 1988).
Patellofemoral pain is commonly seen in activities
involving high-impact or repetitive knee flexion.
Since dance contains both of these elements, it is
not surprising to find patellofemoral pain syndrome
prevalent in the dance population. In a survey of 362
pre-professional and professional modern and ballet
dancers, 38% reported having three or more classic
symptoms of patellofemoral pain syndrome associ-
ated with dance at some time during their dance
training (Clippinger-Robertson et al., 1986).
In addition to the high and repetitive compression
forces associated with dance, there are other underly-
ing anatomical and biomechanical factors that tend
to increase risk for patellofemoral pain. For example,
factors that tend to produce decreased stability of
the patella such as genu recurvatum and weakness
of the vastus medialis—as well as factors that tend
to produce patellar malalignment such as genu
valgum, excessive femoral anteversion, an increased
Q angle, or a tight iliotibial band—can all increase
risk for patellofemoral pain syndrome (Grabiner,
Koh, and Draganich, 1994; Reider, Marshall, and
Warren, 1981; Sheehan and Drace, 1999; Winslow
and Yoder, 1995). Some of these latter malalign-
ments are commonly seen grouped together, and
the composite is termed the miserable malalignment
syndrome as seen in figure 5.34B. In general, patel-
lofemoral pain syndrome occurs more frequently
in females than in males. This is believed to be due
to the greater Q angle and valgus vector associated
with the wider pelvis, the tendency for greater genu
recurvatum, or greater quadriceps weakness found
in females versus males. In essence, patellar instabilityFIGURE 5.33 Meniscal injury (right knee, superior
view). (A) Normal meniscus, (B) small circumferential
tear, (C) partial tear encroaching into the joint (“bucket
handle” tear), (D) tear of posterior area encroaching into
the joint (“posterior horn” tear).