EXTENDED REPORT

Does knee pain in the community behave like a regional pain syndrome? Prospective cohort study of incidence and persistence

K T Palmer¹, I Reading¹, M Calnan², C Linaker¹, D Coggon¹

¹ MRC Epidemiology Resource Centre, Community Clinical Sciences, University of Southampton, Southampton General Hospital, Southampton, England SO16 6YD, UK
² MRC Health Services Research Collaboration, Department of Social Medicine, Canynge Hall, Bristol, England BS8 2PR, UK

Correspondence to:
Dr Keith Palmer
MRC Epidemiology Resource Centre, Southampton General Hospital, Tremona Road, Southampton, SO16 6YD, UK; ktp{at}mrc.soton.ac.uk

Objectives: To investigate whether knee pain in the community behaves like a regional pain syndrome, determined by its association with mental health, self-rated health (SRH) and beliefs about prognosis.

Methods: An 18-month postal follow-up was conducted in 1798 working-aged subjects, sampled from the community. At baseline questions were asked about pain in the knee lasting 1 day in the previous 12 months, mental health (Short-Form 36), somatising tendency (elements of the Brief Symptom Inventory), SRH and concern about 12-month prognosis. At follow-up we asked about knee pain during the last 4 weeks, and whether it had been present for 14 days or prescription-treated. Associations with incidence and persistence were explored using logistic regression.

Results: The 1256 participants (70% response) comprised 468 with knee pain at baseline and 788 without. Among the former, 49% had persistent knee pain at follow-up, while among the latter, 15% reported new symptoms. Incident prescription-treated knee pain was strongly associated with all of the mental health variables and with SRH. The odds of knee pain persisting were significantly raised in the least versus most favourable bands of somatising tendency and SRH, and persistence was also significantly more common among those who at baseline were concerned that they would still have a problem in 12 months.

Conclusions: Our observations support the hypothesis that knee pain in the community shares risk factors in common with other non-specific regional pain syndromes.

Abbreviations: CI, confidence interval; LBP, low back pain; OA, osteoarthritis; OR, odds ratio; SRH, self-rated health

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

• Thomas, E, Peat, G, Mallen, C, Wood, L, Lacey, R, Duncan, R, Croft, P (2008). Predicting the course of functional limitation among older adults with knee pain: do local signs, symptoms and radiographs add anything to general indicators?. Ann Rheum Dis 67: 1390-1398 [Abstract] [Full Text]  
• Palmer, K T, Reading, I, Calnan, M, Coggon, D (2008). How common is repetitive strain injury?. Occup. Environ. Med. 65: 331-335 [Abstract] [Full Text]  
• Jinks, C., Jordan, K. P., Blagojevic, M., Croft, P. (2008). Predictors of onset and progression of knee pain in adults living in the community. A prospective study. Rheumatology (Oxford) 47: 368-374 [Abstract] [Full Text]