Incidence and risk factors for patellofemoral dislocation in adults with Charcot‐Marie‐Tooth disease: An observational study

BACKGROUND AND PURPOSE Patellofemoral (PF) dislocation is frequently encountered in clinical practice among people with Charcot-Marie-Tooth disease (CMT), but the frequency and risk factors for PF dislocation in adults with CMT are unknown. This study aimed to establish the incidence of PF dislocation in adults with CMT and to explore the risk factors associated with PF dislocation. METHODS This is a cross-sectional study involving adults with a diagnosis of CMT, attending their outpatient clinics at a specialist neuromuscular centre in the United Kingdom. Eighty-one individuals were interviewed about any PF dislocation and underwent a lower-limb assessment, with a focussed knee examination, to identify possible risk factors for PF dislocation. The incidence of PF dislocation was expressed as a percentage (number of individuals with a positive history of patellar dislocation/overall sample) and the association between different risk factors and PF dislocation was explored using logistic regression analysis. RESULTS The incidence of PF dislocation was 22.2% (18/81). PF dislocation was associated with a younger age at the time of the assessment (p = 0.038) and earlier disease onset (p = 0.025). All people bar two who dislocated had CMT1A (88.9%), but there was no difference in terms of CMT distribution with the non-dislocation group (p = 0.101). No association was found between PF dislocation and CMT severity measured by CMTSS (p = 0.379) and CMTES (p = 0.534). Patella alta (p = 0.0001), J-sign (p = 0.004), lateral patellar glide (p = 0.0001), generalised joint hypermobility (p = 0.001) and knee flexors weakness (p = 0.008) were associated with an increased risk of dislocation. Patella alta (p = 0.010) and lateral patellar glide (p = 0.028) were independent PF dislocation predictors. CONCLUSIONS PF dislocation was common in this cohort with CMT and was associated with multiple risk factors. Future studies should be conducted to confirm the present findings so that the identified risk factors may be addressed by clinicians through preventive, supportive and corrective measures.

[1]  S. Aaron,et al.  Timed Vibration Sense and Joint Position Sense Testing in the Diagnosis of Distal Sensory Polyneuropathy , 2019, Journal of Neurosciences in Rural Practice.

[2]  P. Ellanti,et al.  The J-sign in patellar maltracking , 2018, BMJ Case Reports.

[3]  R. Lewis,et al.  Prevalence and orthopedic management of foot and ankle deformities in Charcot–Marie–Tooth disease , 2017, Muscle & nerve.

[4]  Sarah A. Moore,et al.  A study of physical activity comparing people with Charcot-Marie-Tooth disease to normal control subjects , 2017, Disability and rehabilitation.

[5]  J. Niu,et al.  The Association of Forefoot Varus Deformity with Patellofemoral Cartilage Damage in Older Adult Cadavers , 2017, Anatomical record.

[6]  J. Belmont,et al.  The 2017 international classification of the Ehlers–Danlos syndromes , 2017, American journal of medical genetics. Part C, Seminars in medical genetics.

[7]  N. Osman,et al.  Patellofemoral instability: Quantitative evaluation of predisposing factors by MRI , 2016 .

[8]  P. Nunes,et al.  Epidemiologic Study of Charcot-Marie-Tooth Disease: A Systematic Review , 2016, Neuroepidemiology.

[9]  S. Ward,et al.  Magnetic Resonance Imaging–Based Topographical Differences Between Control and Recurrent Patellofemoral Instability Patients , 2013, The American journal of sports medicine.

[10]  M. Main,et al.  G.P.90 Dislocating patellae in children with CMT1a , 2012, Neuromuscular Disorders.

[11]  J. Bodurtha,et al.  Ehlers-Danlos Syndrome in Orthopaedics , 2012, Sports health.

[12]  K. Frosch,et al.  Anatomy of Lateral Patellar Instability , 2010, American Journal of Sports Medicine.

[13]  Gerd Diederichs,et al.  MR imaging of patellar instability: injury patterns and assessment of risk factors. , 2010, Radiographics : a review publication of the Radiological Society of North America, Inc.

[14]  R. M. Greiwe,et al.  Anatomy and Biomechanics of Patellar Instability , 2010 .

[15]  Daniel R. Bonanno,et al.  Foot and ankle characteristics in patellofemoral pain syndrome: a case control and reliability study. , 2010, The Journal of orthopaedic and sports physical therapy.

[16]  V. Mattila,et al.  Incidence and risk factors of acute traumatic primary patellar dislocation. , 2008, Medicine and science in sports and exercise.

[17]  Rory O'Sullivan,et al.  The characteristics of gait in Charcot-Marie-Tooth disease types I and II. , 2007, Gait & posture.

[18]  Mike Horton,et al.  The Foot Posture Index: Rasch analysis of a novel, foot-specific outcome measure. , 2007, Archives of physical medicine and rehabilitation.

[19]  E. Nomura,et al.  Generalized joint laxity and contralateral patellar hypermobility in unilateral recurrent patellar dislocators. , 2006, Arthroscopy : the journal of arthroscopic & related surgery : official publication of the Arthroscopy Association of North America and the International Arthroscopy Association.

[20]  H. Dejour,et al.  Factors of patellar instability: An anatomic radiographic study , 2005, Knee Surgery, Sports Traumatology, Arthroscopy.

[21]  Elizabeth W. Paxton,et al.  Epidemiology and Natural History of Acute Patellar Dislocation , 2004, The American journal of sports medicine.

[22]  M. Saleh,et al.  Effect of the Foot on the Mechanical Alignment of the Lower Limbs , 2003, Clinical orthopaedics and related research.

[23]  P. Vinci,et al.  Footdrop, foot rotation, and plantarflexor failure in Charcot-Marie-Tooth disease. , 2002, Archives of physical medicine and rehabilitation.

[24]  J. Holmes,et al.  Foot and Ankle Manifestations of Charcot-Marie-Tooth Disease , 1993, Foot & ankle.

[25]  K. M. Singer,et al.  Patellofemoral Disorders: Physical and Radiographic Evaluation , 1984 .