Fluid accumulation in the joint

Anatomy: The hip joint consists of the hip socket (acetabulum) and the femoral head (caput femoris). The articular surfaces are coated with a cartilage layer a few mm thick, which reduces the load on the articular surfaces.

Cause: Many repeated loads or one violent load can cause an inflammation of the synovial membrane (synovitis), fluid formation, swelling, restriction of movement and pain in the hip joint. The condition is relatively often seen in children (Ultrasonic image).

Symptoms: Pain in the joint upon movement with load. Often there will be movement restriction with rotation of the hip joint.

Examination: It will often be necessary to supplement the ordinary clinical examination with an ultrasound scan, where the fluid in the hip joint can easily be seen (Ultrasonic image).

Treatment: The treatment primarily comprises relief from the pain inducing activity until the swelling has abated. Rehabilitation, within the pain threshold, can subsequently be commenced. In cases of lack of progress with relief the treatment can be supplemented with a medical treatment in the form of rheumatic medicine (NSAID) or by drainage of the joint fluid and the injection of corticosteroid, which should be done with ultrasound guidance.

Complications: In particular you should consider a bacterial infection in the joint (pyarthron), which is determined by ultrasound guided draining of the joint fluid, the child hip diseases (epifysiolysis capitis femoris and Calvé-Legg-Perthes disease), where the joint head on the femur slips or collapses (X-ray examination will determine the diagnosis), arthritis or:

• Tendinitis at the sitting (ischiatic) bone (entesopatia tuber ischii)
• Rupture of the rear thigh muscle attachment to the sitting (ischiatic) bone
• Bursitis at the sitting (ischiatic) bone
• Bursitis at the outer femoral bone projection
• Bursitis on the front of the hip joint
• Piriformis syndrome
• Degenerative arthritis in the hip joint
• Rupture of the superficial hip flexor (ruptura musculus rectus femoris)
• Rupture of the deep hip flexor (ruptura musculus iliopsoas)
• Outer snapping hip
• Inner snapping hip
• Stress fracture of the femoral neck
• Inguinal hernia
• Inflammation of the adductor muscle of the thigh
• Inflammation of the abdominal muscle attachment on the pubic bone
• Inflammation of the pubic bone (osteitis pubis)
• Rupture of the adductor muscle of the thigh
• Nerve entrapment

Special: There are two childrens’ hip diseases that should always be considered in children with hip pain.

• SLIPPING OF THE FEMORAL HEAD IN THE GROWTH ZONE (EPIFYSIOLYSIS CAPITIS FEMORIS), which mainly affects boys age 11-16 years (article). There will often be limping, groin pain, but sometimes the pain is sensed in the knee. It is important in order to obtain a good result from the treatment to be examined by a doctor and have the diagnosis made as soon as possible (with X-rays).

• CALVÉ-LEGG-PERTHES DISEASE is a disease which mainly affects boys age 3-11 years (article). The bone core in the femoral head is dissolved and flattened. There will often be limping, tiredness and pain in the groin, but once in a while the pain is sensed in the knee instead. It is important in order for a good result of the treatment to be examined by a doctor and have the diagnosis made as soon as possible (by means of X-rays or ultrasound).