by T. Ty Fowler, M.D.

Hip pain can vary from an occasional annoyance to a debilitating problem. Symptoms around the hip can present at any age and has many forms and causes consisting of:

  1. Soft tissue strains and irritations in and around the hip
  2. Femoroacetabular impingement (FAI)
  3. Hip dysplasia
  4. Arthritis.

This article focuses on the nagging hip pain that plagues so many young (teens to early fifties) active individuals.

Simply defined, arthritis is the wearing down of the smooth surfaces (articular cartilage) of the hip joint that line both the femoral head (ball) and acetabulum (socket). This can lead to pain, stiffness and an overall loss of function of the leg. There are many theories on why arthritis develops. There has been a great effort over the last 20 years within the orthopaedic community to discover that arthritis in the younger patient is likely due to a mechanical mismatch that eventually increases the wear and tear of the joint that ultimately will progress to arthritis and require a total hip replacement. These mismatches come in two forms, hip impingement and hip dysplasia. Before diving into these conditions, lets explore who and how these patients present.

The typical patients are young active individuals who are involved in sports, hiking, bicycling, yoga, pilates or karate. Other simple activities that can cause hip pain are as follows:

  1. Hip flexion
  2. Sitting for long periods of time
  3. Squatting
  4. Getting in and out of the car
  5. Putting on shoes and socks

The severity of hip pain can vary from an intermittent pain to a constant presence. The symptoms worsen with activity or present the day after a strenuous activity. The characteristics of the hip pain are:

  1. Groin pain that can be sharp, stabbing or even a dull achy sensation
  2. Catching and popping in the hip or groin
  3. Some have a burning fatigue type pain on the outside of their hip

Patients usually seek medical attention at some point and to the untrained eye, will have a relatively normal looking x-ray. These patients are often diagnosed with a hip strain or pulled muscle and treated with over-thecounter medications and recommendations to decrease their activity. This may improve their symptoms in the short-term, followed by a resurgence of their pain once activities are resumed.

An orthopaedic hip preservation specialist should evaluate this type of patient. To diagnose the exact problem will consist of scrutinizing the x-rays (bone evaluation) and sometimes MRI of the hip to evaluate cartilage and soft tissue inside and around the hip.

The two most common diagnoses are femoroacetabular impingement (FAI) with or without a labral tear, and hip dysplasia.

FAI is a condition in which the hip joints have malformations causing the femoral head (ball) and the acetabulum (socket) to rub or come into abnormal contact with each other at extremes of motion causing damage to the cartilage or the labrum (a spongy bumper-like tissue). Over time, this repetitive impact between the two surfaces can eventually be the cause of early arthritis. Usually this diagnosis in association with severe symptoms leads to a recommendation for surgery.

Depending on the severity of the impingement, a hip preservation specialist will have to decide whether a hip arthroscopy (surgery using small incisions, cameras, and instruments) or a surgical hip dislocation is necessary to reshape the femoral head and/or acetabulum, as well as to fix any labral tear that is encountered.

The other diagnosis that can cause hip pain in younger patients is hip dysplasia. Dysplasia means simply, an abnormality in development. Acetabular dysplasia refers to the socket of the hip joint being malformed and misshapen. Most commonly, in dysplasia the acetabulum is shallow and shaped more like a dish, rather than deep and formed like a bowl or cup. It also has a more vertical orientation rather than a horizontal orientation in the normal hip.

Hip dysplasia can have varying degrees of severity and is a developmental condition. Severe hip dysplasia is often times diagnosed and treated during infancy and childhood. However, the milder forms of dysplasia may not lead to a diagnosis at such an early age and therefore go unnoticed throughout ones life until symptoms (pain)present. A dysplastic hip can function for many years without symptoms and the timing of ones symptoms can vary from patient to patient. Some people develop painful symptoms in adolescence and in others, not until their 30’s, 40’s, or later.

The abnormal shape of the socket results in the femoral head to be inadequately covered which leads to improper loading across the joint. This can cause a wearing down of the hyaline cartilage (arthritis), wear and tear on the acetabular labrum or even a stress fracture at the rim of the acetabulum. As in FAI, the longer this process is left untreated the higher likelihood that early arthritis will develop and ultimately need a total hip replacement.

Treatment for acetabular dysplasia is a surgical procedure called a periacetabular osteotomy or PAO. This simply means, “to cut the bone around the acetabulum”. The idea behind a PAO is to treat hip dysplasia in order to prevent or delay arthritis and improve pain. A PAO preserves ones own anatomy by cutting the bone around the acetabulum and 3-dimensionally reorienting the cup in order to restore a near normal relationship between the ball and socket of the hip. By preserving ones own hip, there is a higher likelihood of returning to high-level activities with no restrictions and a pain free hip.

If you feel as though you experience these hip symptoms, please contact an orthopaedic surgeon to discuss your options and further details.