The Cardiovascular
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Recurrent Instability of the Patella (RIP) Score

Predicts long-term recurrence risk after a first-time patellar dislocation.

Recurrent Instability of the Patella (RIP) Score
Age at first dislocation
Skeletal immaturity (open physes)
Trochlear dysplasia (Dejour A-D)
Or lateral trochlear inclination <11 deg or trochlear depth <3 mm on MRI.
TT-TG / patellar length ratio >= 0.5
Result0 points

Low risk: about 0% 10-year recurrent instability.

10-year recurrence
0%

When to use

  • Counselling patients on recurrence risk after a first-time lateral patellar dislocation.

Formula

Points: age <25 years = 2; skeletal immaturity = 1; trochlear dysplasia (Dejour A-D) = 1; TT-TG/PL ratio >=0.5 = 1. Range 0-5. Low 0-1 (0%), intermediate 2-3 (30.6%), high 4-5 (79.2%) 10-year recurrence.

Pearls and pitfalls

  • High-risk patients may be considered for early stabilisation surgery rather than conservative management.

References

  1. Hevesi M, et al. Arthroscopy. 2019;35(2):537-543.