More than 310,000 artificial hip joints are implanted annually in the United States. Successful replacement of deteriorated, arthritic, and severely injured hips has contributed to the enhanced mobility and independence for many people who otherwise would be unable to perform normal daily functions. New technology involving prosthetic devices for replacement of the hip, along with advances in surgical techniques, has diminished the risks associated with the long-term outcome of hip replacement surgery. Questions remain, however, concerning prosthetic design and the materials used.

Sulzer Orthopedics, a major manufacturer of hip implant devices, recently recalled its Inter-Op acetabular shell for hip implants. The recall involved 30,000 hip implants - more than a full year's production. Roughly 17,500 of the recalled hip implants were already in patients.

Sulzer's Inter-Op has a metal ball on a stem that is inserted into the thigh bone. The ball fits into a titanium shell (the "hip shell") lined with plastic that is connected to the pelvis. The hip shell's porous coating is intended to allow bone tissue to grow into the implant. According to Sulzer, oil that was intended to be used only to lubricate the tooling machines producing the hip shells was improperly mixed with coolant that was sprayed on the shells. The oily residue in the hip shell does not bond to the hipbone. As a result, the hip implant becomes loose and the patient can experience severe pain. In some cases, the body reacts to the loose shell by building up scar tissue. The loose shell can then erode the pelvis itself. Sulzer claims that the defect resulted from a faulty manufacturing process.

The Sulzer Inter-Op acetabular shells subject to the recall are as follows:

Symptoms of a defective Inter-Op acetabular shell can be:

Up to 6 weeks after hip replacement surgery:

• The patient may be progressing well or reporting groin or anterior trochanteric pain
• The patient may have increased thigh pain
• The patient has significant startup pain with ambulation (walking) or, rising from a seated position, may have buttock pain
• An x-ray may show possible component migration

6 weeks to 3 months after hip replacement surgery:

• The patient may experience significant pain with weight bearing, and may require a cane or crutch
• The patient may be unable to exert resistance in a straight raised leg test and a side-lying abduction test

Since August 2001, 2,380 patients have undergone new surgery to replace defective Sulzer hips, and there are presently over 1,000 cases pending against Sulzer.

If you or someone you know has had a hip replacement involving a defective Sulzer implant, it is important to seek medical and legal assistance as soon as possible. In all medical product liability cases it is essential that measures be taken promptly to preserve evidence, investigate the procedure in question, and to enable physicians or other expert witnesses to thoroughly evaluate any injuries. If you believe that you may be a victim of a defective hip implant, don't delay! You may have a valid claim and be entitled to compensation for your injuries, but a lawsuit must be filed before the statute of limitations expires.