SNAPPING KNEE

Snapping syndromes are common and often habitual. For some, snapping cause concern but to many it gives feeling of relaxation. The snapping can be physiological and benign. However it can be pathological too. There are number of conditions that cause snapping and over the period of time can be disabling. For sportsman, snapping of joint causes concern. They relate it to potential derangement of their body machine.

Mechanics of habitual snapping
Habitual snapping is common. Most common site is fingers. Whenever a joint is stretched to its maximal range of motion there is some amount of subluxation at the joint. Due to elastic recoil of the supporting tissues, the joint relocates giving the sound. The same holds true for the fascia and muscle tendons. Hence it is the relocation and not the subluxation that results in snap.

Snapping knee
Snapping is rare in knee. Locking of knee is more common.
Types:
Intraarticular.
a) Meniscal tears
b) Loose bodies
c) Patellofemoral disease
d) Arthritis
Extra articular:
a) Abnormal insertion of Biceps Femoris over the fibular head and semitendinosus over medical tibial plateau.
b) Hamstrings rolling over osteochondroma

Management
Confirmation of clinical diagnosis is done by MRI or arthroscopy.
Management can be conservative with balance between strengthening and stretching exercise. Titration of precipitating movement is done.
Surgical treatment is often required. Surgery aims at treatment of cause.