Of the functional tests , squatting demonstrated the highest sensitivity .
Other useful tests include pain during stair climbing and prolonged sitting .
Conclusion A diagnostic checklist is useful as it provides a structured method for diagnosing AKP in a clinical setting .
Background  Anterior knee pain ( AKP ) or patellofemoral pain syndrome is common and may limit an individual 's ability to perform common activities of daily living such as stair climbing and prolonged sitting .
The diagnosis is difficult as there are multiple definitions for this disorder and there are no accepted criteria for diagnosis .
It is therefore most commonly a diagnosis that is made once other pathologies have been excluded .
Objectives The aim of this study was to create an evidence -based checklist for research ers and clinicians to use for the diagnosis of AKP .
Patellofemoral Pain Syndrome: Validity of Clinical and Radiological Features
Data regarding validity of clinical and radiographic findings in diagnosing patellofemoral pain syndrome are inconclusive . We prospect ively assessed how sensitive and specific key patellofemoral physical examination tests are , and evaluated the prevalence of physical examination and radiographic findings . Sixty-one infantry soldiers with patellofemoral pain syndrome and 25 control subjects were evaluated . The sensitivity of the patellar tilt , active instability , patella alta , and apprehension tests was low ( less than 50 % ) ; specificity ranged between 72 % and 100 % . Although the prevalence of positive patellar tilt and active instability tests was significantly greater in subjects with patellofemoral pain syndrome , there were no significant differences between the groups in the results of the other two tests . Soldiers with patellofemoral pain syndrome presented with increased quadriceps angle , lateral and medial retinacular tenderness , patellofemoral crepitation , squinting patella , and reduced mobility of the patella . There were no differences between the groups in the prevalence of lower limb and foot posture alignment and knee effusion .  Plain radiography showed increased patellar subluxation in soldiers with patellofemoral pain syndrome . Other radiographic measures ( sulcus angle , Laurin angle , Merchant angle , and Insall-Salvati index ) were similar in both groups . We provide evidence regarding the validity of clinical and radiographic features commonly used for diagnosing patellofemoral pain syndrome . Physical examinations were more useful than plain radiography . Level of Evidence : Diagnostic study , Level I. See the Guidelines for Authors for a complete description of levels of evidence
Of the functional tests , squatting demonstrated the highest sensitivity .
Other useful tests include pain during stair climbing and prolonged sitting .
Conclusion A diagnostic checklist is useful as it provides a structured method for diagnosing AKP in a clinical setting .
Background  Anterior knee pain ( AKP ) or patellofemoral pain syndrome is common and may limit an individual 's ability to perform common activities of daily living such as stair climbing and prolonged sitting .
The diagnosis is difficult as there are multiple definitions for this disorder and there are no accepted criteria for diagnosis .
It is therefore most commonly a diagnosis that is made once other pathologies have been excluded .
Objectives The aim of this study was to create an evidence -based checklist for research ers and clinicians to use for the diagnosis of AKP .