- Discussion:
- this sign is positive in pts with acute or chronic
posterolateral instability of the knee;
- knee begins in flexion while an
external rotation and valgus stress are applied;
- supine
- valgus stress
- foot in ER
- bring knee from 90 deg flexion to full extension
- feel for palpable “shift” of
lateral tibial plateau as it moves anteriorly from a posteriorly subluxed position
- lateral tibial plateau shifts from position of posterior subluxation to a position of reduction as the flexed knee is
extended under valgus stress and w/ foot in
external rotation; (w/ the true
pivot shift the tibia is internally rotated);
- clunk is appreciatted as the knee is extended;
- plateau subluxates again as knee is flexed in the opposite manner;
- since it describes shift of lateral tibial plateau in opposite direction from true joint shift, its called reverse pivot shift;
- significantly positive reverse pivot shift suggest that
PCL,
arcuate complex, and the
LCL are all torn;
- in the position of tibial inernal rotation, the sign disappears;
Observations on rotatory instability of the lateral compartment of the knee:
Experimental studies on the
functional anatomy and pathomechanism of the true and reversed pivot shift sign.
RP Jakob et al.
Acta. Orthop. Scand. Suppl.
Vol 191. 1981. p 1-32.
