Femoral neck stress fracture: why groin pain should never be ignored

First reported by Asalin, a German military surgeon in 1905⁽¹⁾, a femoral neck stress fracture (which we will abbreviate as ‘FNSF’ from this point on) is a fairly uncommon but potentially very serious injury. Estimates vary, but in healthy young subjects suffering a stress fracture, FNSFs account for between 1% and 7.2% of such injuries⁽²⁾. Like all stress fractures, most FNSFs in athletes are fatigue-induced fractures, which are caused by repetitive loading of normal bone with unsustainable (for the athlete in question) forces⁽³⁾. However, what makes this type of injury particularly serious is that, unlike many other stress fractures, FNSFs are very often not amenable to conservative ‘rest and rehabilitation’ management techniques. This means many will require surgery, especially those that are not diagnosed early (more on this later).

What is a femoral neck stress fracture?

A femoral neck stress fracture is a fracture to the narrow ‘neck’ between the top of the femur bone and the ‘ball’ of the femur (more technically known as the femoral head), which inserts into the hip joint socket - see figure 1. Due to the anatomy and biomechanics of the main thigh bone (the femur) during activities such as running, FHSFs are usually classified according to the location of the fracture origin and the severity/progression.

Figure 1: Anatomy of the femoral neck