title: Occipito-atlanto-axial osteoarthritis: a cross sectional clinico-radiological prevalence study in high risk and general population.
abstract: METHODS
  A cross-sectional clinico-radiologic evaluation of occipito-atlantoaxial (OC1C2) region of 2 population groups.
  
  
  OBJECTIVE
  Determine the prevalence of OC1C2 osteoarthritis in porters involved in carrying loads on the head and general male population. Describe its clinico-radiologic manifestations.
  
  
  BACKGROUND
  In addition to age, head loading is a known cause of degeneration affecting the occipito-cervical region. The impact of head loading in the population aged between third and sixth decade is unknown. Head loading is a common custom in the developing countries.
  
  
  METHODS
  Study group (n = 107) included randomly selected male porters from railway stations who underwent computed tomography (CT) study of the OC1C2 region, plain radiographs of the cervical spine and detailed clinical examination. Control group (n = 107) included randomly selected male patients undergoing CT scan study for diseases of paranasal sinuses with coincidental screening of OC1C2 region along with clinical assessment. The data were analyzed using SPSS 15 software.
  
  
  RESULTS
  Mean age for study group was 32.6 years and controls was 34.6 years (P = 0.156). In the study group, duration of occupational exposure was 10.9 (+/-8.7) years; 81.3% porters being symptomatic with an age of 33.4 (+/-9.6) years. Radiologic prevalence of OC1C2 osteoarthritis in study group was 91.6% and in control group was 6.8%; age of affected individuals was 33.4 (+/-9.3) and 47.9 (+/-8.0) years, respectively. Most common complaint was suboccipital neck pain (69.7%); while the CT finding was decreased joint space with sclerosis and irregularity of the margins (81.3%). No statistically significant association was found between presence of radiologic changes and symptoms. Age, duration of occupational exposure and its relationship with various clinico-radiologic manifestations was studied.
  
  
  CONCLUSIONS
  This condition has significant prevalence in porters, beginning at an early age. Diagnosis is based on the clinico-radiologic presentation. CT is the investigation of choice. Resultant functional limitations make early identification of this condition imperative.
authors.affiliation: Department of Orthopaedics, TN Medical College and BYL Nair Hospital, Mumbai, India. siddharthbadve@hotmail.com
authors.forename: Siddharth A
authors.initials: SA
authors.lastname: Badve
authors.forename: Shekhar
authors.initials: S
authors.lastname: Bhojraj
authors.forename: Abhay
authors.initials: A
authors.lastname: Nene
authors.forename: Abhijit
authors.initials: A
authors.lastname: Raut
authors.forename: Ravi
authors.initials: R
authors.lastname: Ramakanthan
mesh_terms: D000328:Adult; D001268:Atlanto-Axial Joint / Q000000981:diagnostic imaging*; D001269:Atlanto-Occipital Joint / Q000000981:diagnostic imaging*; D016022:Case-Control Studies; D002574:Cervical Vertebrae / Q000000981:diagnostic imaging*; D003430:Cross-Sectional Studies; D003906:Developing Countries; D006801:Humans; D007194:India / Q000453:epidemiology; D017770:Lifting; D008297:Male; D008875:Middle Aged; D009784:Occupational Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D010003:Osteoarthritis / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015995:Prevalence; D012307:Risk Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016474:Weight-Bearing; D055815:Young Adult