Hip Injuries

Hip joint is the joint of stability; it anchors Pelvis and lower limbs through sacroiliac joints and femoroacetabular joints as well complex arrangement of numerous ligaments, muscles and tendons.

Hip motion is controlled by not only thigh muscles but also core muscles along with adductors and gluteus. This architecture allows hip to withstand six to eight times a person’s body weight during walking or running.

Hip injuries are more prevalent in sports involving running or lower limb movements such as soccer, football, hockey, cycling, running, baseball, golf, ballet, gymnasts, weight lifting etc.

Adductor Strain: the adductor muscle complex includes Adductor longus, Adductor magnus, Adductor brevis, obturator externus, gracillis and pectineus. When large mechanical loads are imposed over small tendon of adductor longus, eccentric contraction at the myotendinous unit or adductor enthesis.

Symptoms: Groin pain, pain increases on resisted adduction of hip and passive stretching of adductors. Pain occurs on palpation near pubic bone. Strength and range of motion of adductor muscles are reduced. It is more prevalent in football players.

Athletic Pubalgia/Core muscle injury: also known as sports hernia, weakening or tearing of abdominal wall due to heavy weight lifting or activities in which abdominal pressure increases. Sports involving repetitive pivoting, cutting are also susceptible to this injury. Affected athletes have unilateral or bilateral lower abdominal pain that can be radiate toward the perineum and proximal adductors during sporting activities.

Symptoms: Pain occurs on palpation over pubis, obliques and ractus abdominis insertion. Pain is increased on performing resisted sit-ups and hip adduction. Pain can radiate to the Groin area.
MRI shows cleft sign.

Osteitis pubis: Painful overuse stress injury of pubic symphysis that can cause lower abdominal pain or groin pain secondary to excessive strain or motion of the joint. During core rotation and extension muscles attached to pubis act as antagonists, thus injury to any of these muscles alters the symphyseal biomechanics resulting in stress injury of pubic bone. Later degenerative changes of pubic symphysis can occur from these stresses.

Symptoms: Pain occurs on palpation of pubic area, Positive Spring Test, pain can radiate to the groin area.

Radiological findings: lytic changes at pubic symphysis, sclerosis, widening of the symphysis,

MRI: subchondral bonemarrow oedema.

Hip Dislocation: Dislocation of hip is a rare injury in sport. Posterior dislocations occur when a large force is directed against the flexed knee, with hip flexed, adducted, and internally rotated. The force is typically generated when the athlete’s knee is driven into the ground during a tackle or is struck from behind by another when down on all four limbs in the hands-and-knees position. Anterior dislocations typically occur when the flexed hip is forced into abduction and external rotation in a splits-type injury. These injuries may be seen in sports such as gymnastics and track and field events.

On field management: Palpation of the area reveals significant buttock and abductor muscular spasm. If a dislocation is suspected, checking the thigh lengths at the knee will help confirm the diagnosis. The neurovascular status of the extremity should be examined, including an evaluation of extensor hallucis longus strength, tibialis anterior strength, gastrocnemius strength, and sensation to light touch.The pulse cannot readily be checked on the field without removing the player’s shoe. The patient must be rolled into the supine position while maintaining control of the injured extremity, and minimizing movement at the hip. The position of the injured extremity position is then re-examined to determine if the dislocation is either anterior or posterior. The player with an anterior dislocation prefers an extended, externally rotated, and abducted hip position. The player with a posterior dislocation prefers a flexed internally rotated and adducted position. 

Femoroacetabular Impingement Syndrom (FAI): FAI is the condition of hip in which abnormal, repetitive contact occurs, most commonly between anterolateral femoral head-neck junction and the anterolateral rim of the acetabulum. It can cause cascade of intra-articular breakdown including chondrolabral junction. The loss of internal rotation from cam deformity or retroverted neck causes abnormal contact with acetabular rim earlier in the arc of motion. This block to further motion can initiate impingement and cause injury to the labrum and adjacent articular cartilage, which can lead to osteoarthritis. The loss of motion also produces compensatory hip and pelvic dysfunction through increased extra-articular pelvic motion. The compensatory forces place more stress on the pelvic stabilizers and ultimately can cause a breakdown of pelvic soft tissue structure, leading to inflammation and other hip injuries. The prevalence of FAI is higher in football and hockey players.

Radiography findings: an increased alpha angle on plain radiology was the only predictor of athletic hip/groin pain.