What is Runner’s Knee? (Part 1 of 2)
The phrase “runner’s knee” (RK) is really a generic name for a variety of conditions that cause pain in and about the knee in runners. Unfortunately, that’s about the only thing these conditions have in common, except for their cause, chiefly overuse. Typically, what is most commonly called RK is pain in the region of the kneecap, or in the front of the knee, what we call “anterior” knee pain. The second most common location of pain called RK is on the lateral (outside) side of the knee.
Other symptoms are usually rare, except for stiffness. Any condition which, in addition to pain, causes swelling, or such mechanical symptoms as locking, catching, or real giveaway or instability should not be called RK. In essence, typical RK is not likely to progress to real damage if ignored, or if running continues, hence the distinction.
Pain in the front of the knee can, in itself, stem from a host of causes, such as tendinitis of the quadriceps and patellar tendons which attach to the top and bottom of the kneecap, respectively. This may follow aggressive hill training or racing, increase in mileage, or perhaps from running on the same side of a road with considerable camber (tilt) of the road surface. A pronated, or flat foot, can also contribute to tendinitis via the torque conversion function of the ankle and subtalar joints of the foot. When the foot flattens during the stance phase, the lower leg rotates, and this can produce twisting forces on the knee structures.
Other causes of pain in the front of the knee include pain directly originating from the kneecap. A complete discussion of kneecap problems is far beyond the scope of this article. However, pain from the cap can generally be divided into: pain from surface cartilage problems, pain from malalignment or instability of the kneecap, and pain from the neighboring soft tissues. The actual source of the pain is a moot point, as long as there is no swelling.
Pain in the front of the knee is one of the most common problems seen in the orthopedic office, in runners and non-runners alike. Usually, we try to manage these problems in similar fashion, beginning with cutting back on intensity, and perhaps mileage, avoiding hills, changing roadsides or going alternate directions on a track, increasing stretching, working on quadriceps strengthening exercises, icing knees after workouts, taking medications, and using a knee sleeve. A word about exercises- sole of the foot quad resistance strengthening routines are favored over front of the shin types, as the latter may aggravate the symptoms by increasing pressure behind the cap.
More next time.
What is Runner’s Knee? (Part 2 of 2)
Last time the discussion focused on one type of runner’s knee (RK), that arising in the front (anterior) portion of the knee. Another common type of overuse knee pain is on the outside, or lateral, aspect of the knee. Several tendons may be the primary culprits, but far and away the most common is the iliotibial band. This very long tendon originates at the pelvis, just above the hip joint, as a small fist-sized muscle. The tendon is sheet-like, stretches over the lateral hip (trochanter of the femur- thigh bone), and continues all the way down the thigh to the top of the tibia (leg bone), just below the knee joint.
The problem that usually causes the inflammation, tendonitis, is a small prominence on the femur (thigh bone) just above the knee joint. When the knee bends back and forth, the iliotibial band must slide back and forth over this bump on the outside of the knee. Although this is a normal phenomenon, excessive tightness of this tendon can cause inflammation of the iliotibial band. The runner may feel pain or notice swelling and tightness at this location. The pain is worse during single leg stance, and at 45 degrees of knee flexion (bend). Generalized swelling within the knee joint is not seen, though localized swelling may be noticed..
Contributing factors include inadequate flexibility, hip muscle weakness, excessive pronation, leg-length difference, worn shoes, and running on the same side of the road or in the same direction on a track (especially a banked track). Interestingly, bicyclists are also prone to this condition. The medical term is “iliotibial band friction syndrome” (ITBFS). Although acute (recent onset) ITBFS will often respond to the usual conservative measures of treatment, well-established or chronic tendonitis can be very difficult to eradicate. Therefore, aggressive early treatment is desirable.
Like most other overuse injuries that plague runners, treatment
predictably includes modified activity, vigorous stretching, icing, medication,
etc. One should examine their training regimen for training errors, such
as the technical problems mentioned above. Worn shoes must be discarded.
Try avoiding cambered surfaces, such as the same side of the road, or running in
the same direction on a track. Stretches that focus on the lateral hip,
thigh and knee are very useful and effective. Post-running icing, applied
directly to the symptomatic outside of the knee for ten or fifteen minutes after
a run can help quiet the inflammatory pain, swelling, and stiffness. If
the tendonitis becomes entrenched and chronic, it may be difficult to continue
running while expecting the condition to resolve. However, the vast
majority of these problems will resolve with the assistance of these measures
without injections or surgery.