title: Initial symptoms and delayed diagnosis of osteosarcoma around the knee joint.
abstract: OBJECTIVE
  To identify initial symptoms of osteosarcoma around the knee joint.
  
  
  METHODS
  Records of 19 men and 11 women aged 9 to 34 (mean, 17) years with osteosarcoma around the knee joint were reviewed. Each patient was interviewed (for a mean of 1.5 hours), and a detailed history of symptom onset recorded.
  
  
  RESULTS
  In all patients, the first symptom was pain, which was more pronounced on weight bearing in 16 (53%) of them and was worse at night in 11 (37%). Swelling was noticed in 28 patients (a mean of 7 weeks after pain onset). 16 (53%) of the patients had a history of minor trauma around the time of symptom onset. 20 (67%) of the patients had a limp, in 9 of whom it was not associated with pain on weight bearing; only 2 (7%) had a pathological fracture. The mean interval from the onset of symptoms (pain) to presentation was 10 (range, 0-49) weeks. The mean interval from presentation to radiography was 3 (range, 0-20) weeks; in 8 patients this interval exceeded 3 weeks despite a noticeable swelling. The mean interval from radiography to referral to our hospital was 2 (range, 0-14) weeks. Together with the 2 weeks for diagnostic workup and biopsy, the mean total delay was 17 (range, 4-55) weeks.
  
  
  CONCLUSIONS
  Physicians should be aware of the symptoms of osteosarcoma and promptly refer patients to tumour centres, especially adolescents, those who present with pain that may be worse at night and on weight bearing, and those in whom a swelling and/or a limp is evident.
authors.affiliation: Department of Orthopaedics, Faculty of Medicine and Health Sciences, Universiti Malaysia Sarawak, Sarawak General Hospital, Kuching, Sarawak, Malaysia. klpan@fmhs.unimas.my
authors.forename: Kok Long
authors.initials: KL
authors.lastname: Pan
authors.forename: Wai Hoong
authors.initials: WH
authors.lastname: Chan
authors.forename: Yin Yin
authors.initials: YY
authors.lastname: Chia
mesh_terms: D000293:Adolescent; D000328:Adult; D001859:Bone Neoplasms / Q000150:complications* / Q000175:diagnosis* / Q000628:therapy; D002648:Child; D015331:Cohort Studies; D057210:Delayed Diagnosis; D005260:Female; D006801:Humans; D007719:Knee Joint; D007867:Leg Bones; D008297:Male; D012516:Osteosarcoma / Q000150:complications* / Q000175:diagnosis* / Q000628:therapy; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D016474:Weight-Bearing; D055815:Young Adult