title: Generalized joint hypermobility in professional dancers: a sign of talent or vulnerability?
abstract: OBJECTIVE
  To study the impact of generalized joint hypermobility (GJH) in professional dancers on physical fitness, musculoskeletal complaints and psychological distress.
  
  
  METHODS
  Thirty-six professional dancers were recruited and compared with control subjects (mean age 20.1, range 17-27). Height, weight, Beighton score, physical fitness (walking distance, muscle strength, estimated VO2max), musculoskeletal complaints (pain, fatigue) and psychological distress (anxiety, depression) were measured.
  
  
  RESULTS
  Univariate analysis revealed, in between-group analysis, that dancers (with and without GJH) had higher physical fitness [the six-minute walk test (6MWT): ΔD = +8.4%, P = 0.001; VO2max: ΔD = +12.8%, P = 0.01], fatigue (checklist individual strength: ΔD = +80.3%, P < 0.0001) and greater psychological distress (Hospital Anxiety and Depression Scale: ΔD = +115.0%, P < 0.0001). When comparing dancers and control subjects with GJH to those without GJH, lower levels of physical fitness (muscle strength: ΔD = -11.3%, P < 0.0001; 6MWT: ΔD = -9.9%, P < 0.0001), more fatigue (checklist individual strength: ΔD = +84.4%, P < 0.0001) and greater psychological distress (Hospital Anxiety and Depression Scale: ΔD = +79.6%, P < 0.0001) were observed in subjects with GJH. Multivariate analysis showed that dancers have higher levels of physical fitness (6MWT, P = 0.001; VO2max, P = 0.020); however, when taking GJH into account, this advantage disappeared, indicating lower levels of physical fitness in comparison with control subjects (6MWT, P = 0.001; muscle strength, P < 0.0001; VO2max, P = 0.040). Dancers experienced more fatigue (P = 0.001) and psychological distress (P < 0.0001). This was associated with even more fatigue (P = 0.010) and psychological distress (P = 0.040) when GJH was present.
  
  
  CONCLUSIONS
  Dancers with GJH seem more vulnerable to musculoskeletal and psychological complaints. In addition, GJH was also associated with lower physical fitness, despite training. Caregivers for professional dancers should monitor closely the physical capabilities and the amount of psychological strain.
authors.affiliation: Education of Physiotherapy, Amsterdam School of Health Professions, University of Applied Sciences, Amsterdam, The Netherlands. m.c.scheper@hva.nl
authors.forename: Mark C
authors.initials: MC
authors.lastname: Scheper
authors.forename: Janneke E
authors.initials: JE
authors.lastname: de Vries
authors.forename: Rien
authors.initials: R
authors.lastname: de Vos
authors.forename: Jeanine
authors.initials: J
authors.lastname: Verbunt
authors.forename: Frans
authors.initials: F
authors.lastname: Nollet
authors.forename: Raoul H H
authors.initials: RH
authors.lastname: Engelbert
mesh_terms: D000293:Adolescent; D000328:Adult; D001007:Anxiety; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D003615:Dancing; D003863:Depression; D005221:Fatigue; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis*; D053580:Muscle Strength; D009784:Occupational Diseases / Q000175:diagnosis*; D010146:Pain; D010809:Physical Fitness; D013315:Stress, Psychological; D055815:Young Adult