title: [The "false sense of absence" of the lower extremity below the knee: is it a specific sign for anterior cruciate ligament ruptures?].
abstract: OBJECTIVE
  Patients whose anterior cruciate ligament (ACL) was completely ruptured described a feeling as if they had lost their lower extremity below the knee and gave an account that they had not sensed that part of their extremity at the time of ACL rupture. Thinking that this description might denote a diagnostic sign, an investigation was made to verify this feeling in patients whose ACL rupture was confirmed by knee arthroscopy.
  
  
  METHODS
  The described feeling was named as "false sense of absence." A total of 135 patients with knee trauma were included. Those whose injuries were complicated or who had multiorgan injuries were excluded. The patients were divided into two groups according to whether they had ACL rupture (95 patients; 89 males, 6 females; mean age 28 years; range 15 to 50 years) or other knee injuries (40 patients; 34 males, 6 females; mean age 35 years; range 13 to 60 years). The above-mentioned symptom was questioned in both groups.
  
  
  RESULTS
  The described symptom was found in 87% of patients with ACL rupture and in none of the patients with other knee pathologies (p<0.001). The specificity, sensitivity, positive and negative predictive values of this symptom in ACL ruptures were found as 100%, 98%, 100%, and 95%, respectively.
  
  
  CONCLUSIONS
  The "false sense of absence" symptom, which has hitherto been undescribed in the literature, seems to occur in the majority of patients with ACL ruptures; it may be a specific and sensitive finding in determining ACL ruptures, and thus, may merit inclusion in the process of history taking.
authors.affiliation: Uludağ Universitesi Tip Fakültesi Ortopedi ve Travmatoloji Anabilim Dali, Bursa, Turkey. burakdemirag@hotmail.com
authors.forename: Burak
authors.initials: B
authors.lastname: Demirağ
authors.forename: Tolga
authors.initials: T
authors.lastname: Kaplan
mesh_terms: D000293:Adolescent; D000328:Adult; D000070598:Anterior Cruciate Ligament Injuries; D001182:Arthroscopy; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007718:Knee Injuries / Q000175:diagnosis* / Q000473:pathology; D007719:Knee Joint / Q000294:innervation* / Q000502:physiology; D008297:Male; D008465:Mechanoreceptors / Q000502:physiology; D008487:Medical History Taking / Q000592:standards*; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity