Pain after Hip Replacement
Potential Symptoms & Adverse Effects
of Metal on Metal Hip Implants

Introduction

The focus of this page is pain after hip replacement caused by metal on metal hip implants.

Recipients of metal on metal hip implants face the same (general) adverse risks from hip replacement surgery as do recipients of other types of hip implant including: dislocation, infection, component loosening, device breakage, bone fracture, bone loss.

The symptoms that might arise from these adverse risks include: changes in ability to walk; pain in the groin or hip area; swelling; numbness.

However, beyond the (general) adverse risks listed above, the metal particles that can be released by metal on metal hip implants can cause additional adverse effects as summarized below.

Possible adverse medical effects caused by Metal on Metal Hip Implants

The potential adverse medical effects of metal on metal hip implants fall into one of two categories:

  • Physical symptoms that are local to the hip area
  • Symptoms possibly caused by metal particles entering the bloodstream

Physical symptoms

Metal particles released from a metal on metal hip implant may cause a local reaction around the hip joint, which may lead to deterioration in tissue and / or bone around the hip joint, loosening of implant components and the potential failure of the hip device. Any one of these problems could be the underlying cause of pain after hip replacement.

These symptoms are sometimes referred to as adverse local tissue reaction (ALTR) or adverse reaction to metal debris (ARMD).

Symptoms caused by metal particles entering the blood (systemic toxicity)

Metal particles from a metal on metal hip implant may enter the bloodstream. There is emerging evidence that suggests that some patients with metal on metal hip implants may have experienced adverse reactions to these metal particles and that a range of medical problems might therefore be related to their metal on metal implants (see note 1 below) These problems include:

  • Neurological problems including sensory changes: visual impairment; auditory impairment
  • Skin rashes (hypersensitivity reaction)
  • Change in psychological status, including possibly cognitive impairment or depression
  • Thyroid problems which might result in: weight gain, tiredness, neck pain, feeling cold
  • Cardiomyopathy - heart muscle disease potentially resulting in a measurable deterioration in the performance of the heart muscle
  • Impairment of the renal (kidney) function

Note 1 : It is important to note that (as at Sept 2012) the evidence collected globally does not yet establish a definitive link between the use of metal-on-metal implants and the symptoms listed immediately above, but research is ongoing to establish whether there is a definitive (cause and effect) link.

Summary

Regardless of the timing of when symptoms present, and irrespective of the type of hip implant received, any patient experiencing any unexpected pain after hip replacement should discuss it with their orthopaedic surgeon or other appropriate health professional.