Most hip pain in adults under 50 has a structural cause that developed long before symptoms appeared. Understanding what is actually driving the pain changes everything about how it gets treated. Identifying the underlying cause early, before permanent damage has occurred, is the difference between preserving a joint for decades and replacing it prematurely.
Why hip pain is often misattributed
Hip pain is frequently attributed to general wear and tear, ageing or a non-specific soft tissue injury. While these explanations are sometimes correct, they are often incomplete. The hip is a mechanically complex joint, and pain in the groin, outer hip or thigh is frequently the result of a structural abnormality that has been present since childhood or adolescence, altering the mechanics of the joint in a way that causes progressive damage over years.
In fact, at least 80 per cent of hip osteoarthritis in adults is caused by a developmental abnormality. The pain may not begin until the patient is in their 30s or 40s, but the underlying problem has typically been present since birth or early childhood. By the time pain develops, some degree of joint damage has usually already occurred.
The most common underlying causes
Hip dysplasia
Hip dysplasia describes a condition in which the acetabulum (socket) is too shallow to fully cover the femoral head (ball). The socket fails to distribute load evenly across the joint surface, concentrating it on the rim of the acetabulum. Over years, this rim overload causes damage to the labrum and cartilage, leading to pain and, eventually, osteoarthritis.
Dysplasia is more common in females and is frequently not identified until a patient presents with groin pain in their 20s or 30s. On a standard X-ray taken by a GP or emergency department, mild dysplasia can appear almost normal if the viewer does not know what to look for. A specialist hip assessment using standardised X-ray views is required to identify it reliably.
Femoroacetabular impingement (FAI)
FAI occurs when the shape of the femoral head or acetabulum causes abnormal contact between the bones during hip movement. This contact damages the labrum and cartilage over time. It is particularly common in males who participated in high-level sport during adolescence, though it also affects females and non-athletes.
Many people with FAI do not experience significant pain until they are in their 20s or 30s, when the accumulated cartilage damage crosses a threshold and becomes symptomatic. At that point, the impingement has often been present and causing damage for years.
Residual effects of childhood hip conditions
Conditions such as Perthes disease and slipped upper femoral epiphysis (SUFE) affect the hip during childhood and adolescence. Even when treated appropriately at the time, these conditions can leave residual deformity of the femoral head that causes impingement and abnormal joint loading in adulthood. Many adults presenting with hip pain in their 30s and 40s have a history of a childhood hip condition that was considered resolved, but has left a structural legacy.
Why early diagnosis matters
Cartilage does not regenerate meaningfully once damaged. Joint preservation surgery, including hip arthroscopy and periacetabular osteotomy, works best when the cartilage is still largely intact. Once significant cartilage loss has occurred, preservation becomes less viable and the path leads toward replacement rather than preservation.
This is why the timing of diagnosis matters as much as the diagnosis itself. A patient identified with hip dysplasia at 28 with well-preserved cartilage has very different options to the same patient presenting at 42 with significant cartilage loss. In the first scenario, a periacetabular osteotomy may preserve the hip for decades. In the second, replacement may be the more appropriate option.
What to do if you have unexplained hip or groin pain
If you have persistent hip or groin pain that has not responded to physiotherapy or general management, a specialist orthopaedic assessment is worth pursuing. Bring any existing imaging to the appointment. If no imaging has been taken, Mr Balakumar will arrange a specific set of standardised X-ray views that are designed to identify structural abnormalities that standard views may miss.
The assessment includes a thorough history, physical examination and imaging review. If a structural cause is identified, the treatment options are discussed in full, including non-surgical management, joint preservation surgery and, where appropriate, joint replacement. The goal is always to find the right treatment for the right patient at the right time.
