Belgian decathlete Thomas Van der Plaetsen had testicular cancer diagnosed because abnormal levels of the HCG hormone were detected on a routine doping test in 2014. After treatment, 2016 saw him win the European Championships and compete at the Rio 2016 Olympic Games.
Not every patient who presents to the sport and exercise medicine clinician has a sports-related condition. Sport and exercise medicine has its share of conditions that must not be missed—‘red flag’ conditions that may appear at first to be rather benign. For example, a patient diagnosed with a minor ‘calf strain’ may have a deep venous thrombosis or a young basketball player with proximal anterior tibial pain who has been labelled as having Osgood–Schlatter disease may have an osteosarcoma or giant cell tumour of the proximal tibia. In this chapter we:
outline a clinical approach that should maximise your chances of recognising a condition that is ‘masquerading’ as a sports-related condition
describe some of these conditions to illustrate how they can present.
HOW TO RECOGNISE A CONDITION MASQUERADING AS A SPORTS INJURY
Three key factors will assist the clinician to avoid missing an atypical or masquerading condition. The first is keeping an open mind to the possibility. Too often, we become more rigid regarding our initial diagnosis rather than being open to consider other possibilities. Sometimes a fresh perspective from a colleague can be helpful in this regard.
The second and perhaps most important key is obtaining a detailed and complete history and physical examination. If you do not ask the question or consider a broader differential diagnosis, it is impossible to pick up the subtle clues pointing to a less likely but masquerading condition. Indeed, if the concept of a masquerading condition is not triggered from the history and examination, it is unlikely that appropriate investigations to make the diagnosis will be ordered. For example, if a patient presents with tibial pain and it is, in fact, due to hypercalcaemia secondary to lung cancer, a bone scan of the tibia looking for stress fracture will usually not help with the diagnosis, but a history of weight loss, occasional haemoptysis and associated abdominal pain may. In a basketball player with shoulder pain, the history of associated arm tightness and the physical finding of prominent superficial veins are important clues to axillary vein thrombosis; a grey-scale ultrasound scan looking for rotator cuff tendinopathy will not provide the diagnosis.
In sports medicine, it may seem simple to jump to the obvious conclusion regarding a specific diagnosis but if more in-depth questions or a thorough physical exam are not completed, it is difficult to be alert to a less common or ‘non-obvious’ diagnosis.
A third important key that points to masquerading conditions is when the clinical progression does not fit the pattern expected of the more common diagnosis ...