Patella baja

Patella baja (or patella infera) is an abnormally low lying patella, which is associated with restricted range of motion, crepitations and retropatellar pain. If long standing extensor dysfunction may ensue with significant morbidity.  It is seen in a variety of clinical scenarios including 1:

  • quadriceps dysfunction:
    • poliomyelitis
    • tourniquet paralysis
  • bony or ligamentous trauma:
    • fractures
    • osteotomies
    • tibial tubercle transplant
    • ACL repair
    • total knee replacement: seen in 25% of patients 1

Radiographic features

A number of methods for determining patella height have been devised:

It is important in the setting of previous surgery to ensure that the patella has not been resected, as change in patellar morphology will clearly affect the ratio 1.

Treatment and prognosis

Patella baja, when post traumatic/surgical is uncommonly asymptomatic and requires early surgical correction as conservative measures are rarely successful. Treatment requires either a tibial tuberosity osteotomy and re-implantation proximally or patellar tendon lengthening.

Knee pathology

The knee is a complex synovial joint that can be affected by a range of pathologies:

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Article information

rID: 7498
Section: Gamuts
Tag: knee
Synonyms or Alternate Spellings:
  • Patella infera
  • Low lying patella

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Cases and figures

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    Normal patella
    Fig 1: normal patella: sag T2 FS
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    Case 1: with concurrent lateral tilt
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    Low riding of the...
    Case 2
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