Fusion of double-layered patella using a single small fragment partially threaded screw: a case report

J Pediatr Orthop. 2011 Mar;31(2):e9-e12. doi: 10.1097/BPO.0b013e318207454b.

Abstract

Background: The double-layered patella (DLP) was first described by Büttner in 1925 and is now considered pathognomonic for multiple epiphyseal dysplasia. In this study, we describe the case of an 11-year-old girl with multiple epiphyseal dysplasia and right-sided DLP.

Methods: The patient presented with intermittent unilateral anterior knee pain and swelling. There was a reproducible high-pitched click with every step. Imaging showed a DLP in good alignment. Surgical management comprised open debridement and fixation of the 2 patellar layers using one 3.5 mm (removed-) partially threaded AO small fragment screw.

Results: Standard radiographs of the right knee, 3 years postoperatively, showed sound union of the 2 patellae. The patient now plays sports, and recent examination showed a full range of movement with no instability, effusion, or tenderness.

Conclusions: We conclude that surgical fusion of the patellar fragments in DLP using a single small fragment partially threaded screw provides excellent outcome at 3 years follow-up.

Clinical relevance: This case report shows a comparatively simple and economical surgical solution to the problem of DLP.

Publication types

  • Case Reports

MeSH terms

  • Bone Screws
  • Child
  • Female
  • Follow-Up Studies
  • Humans
  • Knee Joint / diagnostic imaging
  • Knee Joint / physiopathology
  • Orthopedic Procedures / instrumentation
  • Orthopedic Procedures / methods*
  • Osteochondrodysplasias / complications*
  • Patella / abnormalities
  • Patella / diagnostic imaging
  • Patella / surgery*
  • Radiography
  • Range of Motion, Articular
  • Treatment Outcome