title: Cervical cord compression in mucopolysaccharidosis VI (MPS VI): Findings from the MPS VI Clinical Surveillance Program (CSP).
abstract: To gain insight into the frequency, age of onset, and management of cervical cord compression in mucopolysaccharidosis VI (MPS VI).
  
  
  
  Cervical spine magnetic resonance imaging (MRI) data and/or cervical decompression surgery data collected between 30 June 2005 and 1 September 2015 were analyzed from subjects enrolled in the MPS VI Clinical Surveillance Program (CSP) (ClinicalTrials.gov: NCT00214773), an ongoing multicenter, observational, retrospective and prospective registry.
  
  
  
  Of 213 subjects enrolled in the CSP, 134 (62.9%) had at least one documented cervical spine MRI assessment. An additional four subjects were identified through surgery records alone to yield a study population comprising 138 subjects (mean age at enrollment =15.1years; age range=0.80-65.0years). Cervical cord compression was documented in 101 (75.4%) of the 134 subjects with ≥1 MRI assessment, the majority (95.0%) by the time of the first recorded MRI. In general, subjects with cervical cord compression had significantly lower height Z-scores compared to those without cervical cord compression (p<0.0001); nevertheless, a few subjects of taller stature had documented cervical cord compression at a young age. Most subjects >20years of age (31/33, 93.9%) presented with cervical cord compression. There was an insufficient number of subjects with both pre- and post-enzyme replacement therapy (ERT) MRI data to determine any association between ERT and cervical cord compression. Surgical decompression was performed on 58 subjects (42.0%), with mean age at first surgery of 13.1years. Decompression plus stabilization procedures accounted for 12.1% of surgeries. Eight subjects (13.8%) underwent reoperation. Complications during or following surgery were reported in 3 subjects, with anesthesia-related complications resulting in two deaths.
  
  
  
  All individuals with MPS VI are at high risk of developing cervical cord compression at an early age. Routine MRI assessments should be initiated from the time of MPS VI diagnosis. The perioperative management of MPS VI patients can be challenging. This study contributes to the understanding of the natural history of MPS VI.
authors.affiliation: Birmingham Children's Hospital NHS Foundation Trust, Birmingham, UK. Electronic address: guirish.solanki@bch.nhs.uk.
authors.forename: Guirish A
authors.initials: GA
authors.lastname: Solanki
authors.affiliation: UCSF Benioff Children's Hospital Oakland, Oakland, CA, USA.
authors.forename: Peter P
authors.initials: PP
authors.lastname: Sun
authors.affiliation: UCSF Benioff Children's Hospital Oakland, Oakland, CA, USA.
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Martin
authors.affiliation: Manchester Academic Health Science Centre, Salford Royal Foundation NHS Trust, Manchester, UK; Steve Biko Academic Unit, University of Pretoria, South Africa.
authors.forename: Christian J
authors.initials: CJ
authors.lastname: Hendriksz
authors.affiliation: Helios Dr. Horst Schmidt Kliniken, Wiesbaden, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Lampe
authors.affiliation: Hôpital Femme Mère Enfant, Lyon, France.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Guffon
authors.affiliation: Advance Research Associates, Santa Clara, CA, USA.
authors.forename: Annie
authors.initials: A
authors.lastname: Hung
authors.affiliation: BioMarin Europe Limited, London, UK.
authors.forename: Zlatko
authors.initials: Z
authors.lastname: Sisic
authors.affiliation: BioMarin Pharmaceutical Inc., Novato, CA, USA.
authors.forename: Renée
authors.initials: R
authors.lastname: Shediac
authors.affiliation: UCSF Benioff Children's Hospital Oakland, Oakland, CA, USA.
authors.forename: Paul R
authors.initials: PR
authors.lastname: Harmatz
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D066193:Cervical Cord / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging / Q000503:physiopathology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009087:Mucopolysaccharidosis VI / Q000000981:diagnostic imaging / Q000503:physiopathology*; D013117:Spinal Cord Compression / Q000000981:diagnostic imaging / Q000503:physiopathology*; D055815:Young Adult
keywords: MPS VI; Maroteaux-Lamy syndrome; Mucopolysaccharidosis VI; cervical cord compression; cervical decompression surgery; spinal cord compression