Anterior cruciate ligament injury: A persistently difficult diagnosis

Historically anterior cruciate ligament (ACL) injuries have been diagnosed poorly. A paper published in Injury in 1996 showed that less than 10% of patients with an ACL injury had the diagnosis made by the first physician to see them and that the average delay from first presentation to diagnosis was 21 months. The aim of our study was to investigate whether an improvement has been made over the last two decades in diagnosing ACL injuries.

We identified 160 patients who had an ACL reconstruction performed by a single surgeon between October 2004 and December 2011 and for whom a complete data set was available. Data was extracted retrospectively from the hospital notes and a dedicated patient database. We performed a sub-group analysis comparing patients seen prior to the introduction of an acute knee injury clinic in April 2007 and patients seen after the introduction of the clinic.

75.1% (120/160) of patients presented first to an emergency department (ED) or to their general practitioner (GP), but only 14.4% (23/160) were diagnosed on initial presentation. The median number of healthcare professionals a patient saw prior to a diagnosis of ACL injury was 3. The median delay from injury to presentation was 0 weeks (range 0-885), injury to diagnosis 13 weeks (0-926), presentation to diagnosis 10 weeks (0-924), presentation to a specialist knee clinic 24 weeks (0-1006), and specialist knee clinic to surgery 13 weeks (0-102). The median total time from injury to surgery was 42 weeks (0-1047). Following the implementation of an acute knee injury clinic in 2007, the median delay from presentation to surgery dropped from 59 weeks to 36 weeks (p = 0.050) and there was a significant decrease in the median delay from specialist knee clinic to surgery from 23 to 11 weeks (p=0.002).

Over the past two decades there appears to have been little improvement in the early diagnosis of ACL injuries, with only 14.4% of patients being diagnosed correctly at initial presentation. We recommend further education of emergency and primary care clinicians in the diagnosis of ACL injuries, emphasising the importance of the typical history of an ACL injury. The implementation of an acute knee injury clinic may help minimise delays to surgery, which should result in better patient outcomes.