A Guide To Hip Injuries And Lower Extremity Ramifications In Female Athletes

   Many runners will consult a sports podiatrist for their lower extremity injuries. It is very important to have an understanding of lower extremity biomechanics and the mechanism behind running injuries. Surrounding yourself with other sports medicine specialists is very important in facilitating appropriate referrals and the best multidisciplinary care.

   Accordingly, let us take a closer look at some of the more common hip injuries in the female athlete and how they may contribute to lower extremity issues.

   Although hip injuries can occur in any sport, runners and soccer players are at increased risk. The complexity in and around the pelvis and hip often makes a diagnosis difficult.

   There are distinct differences between the male and female pelvis. Females generally have a lower body mass and their pelvic anatomy reflects these features. The female bones and joints are smaller, and the markings for ligament and tendon attachments are less pronounced. The pelvis in the female is larger than in the male. The amount of femoral anteversion is higher in females. Also the pubic symphysis in the female has a wider fibrocartilage disc. Females tend to have more ligamentous laxity and overpronation.

   These anatomical differences reflect the functional differences between the male and female, and may contribute to the increase in lower extremity injuries in the female athlete.

   Muscle and tendon injuries are common around the hip and pelvis of the female athlete. Muscle strains and pulls about the pelvis comprise most of these injuries. In the skeletally immature patient, one must consider an apophyseal injury at the bony origin. The muscles that are typically involved include the iliopsoas, adductors, gluteals, sartorius and rectus femoris muscles. Pain with isolated testing of the injured muscle will help clarify the diagnosis.

Pertinent Pointers On Common Hip Injuries

   Bursitis. This injury consists of a viscous fluid sac located in areas that produce friction over bony prominences and between tendons. The most commonly inflamed bursae are the trochanteric, iliopectineal and ischial bursae (the trochanteric bursae being the most commonly affected). Athletes may describe a snapping sensation at the greater trochanter, which is a result of the iliotibial band passing over the greater trochanter.

   Iliopsoas muscle strain. The major actions of these muscles are to provide hip flexion. Anterior tilting in the sagittal plane causes a contraction of the hip flexors. The symptoms most often reported are pain in the groin area and lower back pain when the patient is running or walking. Tenderness may be present along the course of the tendon and at the insertion.

   Piriformis syndrome. The major action of the piriformis is external rotation of the hip. Common complaints here include “pain in the buttocks.” This often can be confused with sciatica. The sciatic nerve passes immediately below the piriformis muscle and, in some people, the sciatic nerve can actually travel through the piriformis muscle.

   Hip labral tear. The socket of the hip joint is lined by cartilage called the labrum. This cartilage provides stability and cushioning for the hip joint. These tears can result from injury or repetitive movements that cause wear and tear on the hip joint. In many cases, a hip labral tear causes no signs or symptoms, and does not require treatment. Occasionally, a hip labral tear may cause pain or a “catching” sensation in the hip joint. Oftentimes, the athlete does not recall a particular incident, which triggered the pain.

   Iliotibial band syndrome. This is a fascia strip that passes down the lateral aspect of the thigh from the crest of the ilium and inserts into the lateral tibial condyle. As the knee flexes and extends during running, this band repeatedly rubs over the lateral femoral condyle. This causes inflammation and pain. There is direct correlation between hip abductor (gluteus medius) weakness and iliotibial band syndrome.

Essential Insights On Fractures

   Stress fractures. When a stress fracture of the hip occurs in females, one must consider contributing factors such as hormone levels, bone density, diet, the patient’s training program and biomechanical abnormalities. (See “Key Points To Consider When Assessing Female Athletes” below.)

   Stress fractures in the pelvis account for 1 to 5 percent of all stress fractures that occur as a result of running. Within the pelvis, stress fractures occur most often in the inferior pubic ramus medially close to the pubic symphysis. Studies have shown that the differences in gait between men and women may account for the increase in tension in the pubic rami. The female runner relies on hip extension forces more than the male runner. This leads to more stress on the area, thus increasing the likelihood of a stress fracture.

   Sacral stress fractures. In runners, sacral stress fractures are believed to be the result of cyclic loading of the sacrum. One should consider sacral stress fractures if the female athlete complains of low back pain or pain radiating into the buttocks or groin, or down the leg.

   Femoral neck stress fractures. During running, loads on the femoral head can exceed three to five times the body weight. During prolonged or repetitive activity, the hip musculature becomes weakened and fatigued, and can no longer provide a protective shock absorbing effect. This leads to increased stress on the femoral neck. There are two types of femoral neck stress fractures: compression and tension. A compression stress fracture occurs on the inferiomedial aspect of the femoral neck and is considered stable. These fractures heal with conservative treatment.

   A tension femoral neck stress fracture occurs on the superolateral aspect of the neck and is at increased risk for fracture displacement. These fractures require internal fixation.

In Conclusion

   To prevent injuries about the hip and pelvis from becoming chronic, it is important to facilitate a precise and early diagnosis. Ensuring appropriate referrals is key. For example, it is imperative to obtain a MRI on the female athlete’s hip if she presents with “vague hip pain.”

   Institution of a core strengthening program is very important. The prevention of lower extremity injuries may involve strengthening the pelvis and dealing with any biomechanical imbalances in the foot, ankle and leg.

Dr. Connors and Dr. Sanz have a sports medicine practice with offices in New York City and in Little Silver, N.J.

Dr. Richie is an Adjunct Associate Professor in the Department of Applied Biomechanics at the California School of Podiatric Medicine at Samuel Merritt College. He is a Fellow of the American Academy of Podiatric Sports Medicine.

References:

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