Case report: Congenital knee dislocation in a patient with larsen syndrome and a novel filamin B mutation.
We treated a patient with multiple congenital joint dislocations and facial dysmorphisms consistent with Larsen syndrome. Sequencing of the FLNB gene resulted in identification of a novel, de novo 508G>C point mutation resulting in substitution of proline for a highly conserved alanine (A170P). This mutation has not been described previously but is likely causative because this alanine is highly conserved and is located in the calponin homology domain where other mutations have been described. We also report the successful use of a minimally invasive technique in achieving initial correction of bilateral congenital knee dislocations in this patient. The technique consists of serial manipulations and castings followed by an open quadriceps tenotomy. Longer followup is needed to ensure maintenance of correction and to avoid the need for more extensive surgery, which has been the traditional treatment for congenital knee dislocation associated with Larsen syndrome.
Dobbs
Matthew B
MB
Department of Orthopaedic Surgery, Washington University School of Medicine, One Children's Place, Suite 4S20, St Louis, MO 63110, USA. dobbsm@wudosis.wustl.edu
Boehm
Stephanie
S
Grange
Dorothy K
DK
Gurnett
Christina A
CA
D000015:Abnormalities, Multiple / Q000235:genetics*; D003285:Contractile Proteins / Q000235:genetics*; D064448:Filamins; D006801:Humans; D007223:Infant; D031221:Knee Dislocation / Q000151:congenital* / Q000235:genetics* / Q000601:surgery; D008297:Male; D008840:Microfilament Proteins / Q000235:genetics*; D009139:Musculoskeletal Abnormalities / Q000235:genetics*; D009154:Mutation / Q000235:genetics*; D013577:Syndrome
D003285:Contractile Proteins; C578662:FLNB protein, human; D064448:Filamins; D008840:Microfilament Proteins