Complications of Total Knee Replacement
POTENTIAL COMPLICATIONS OF TOTAL KNEE REPLACEMENT
Rhidian Morgan-Jones
SPECIFIC COMPLICATIONS
INFECTION
Despite surgery under sterile conditions, infection is still a potential complication of all operations. Post-operative infection maybe:
a)SuperficialWounds only and usually settles with antibiotics.
b)DeepInvolving the joint. Requires further surgery to debride the joint and intravenous antibiotics. Often a revision operation, with exchange of implants, is needed to eradicate the infection
DEEP VENOUS THROMBOSIS & PULMONARY EMBOLUS
A blood clot in the deep veins of the calf or thigh is a complication of any lower limb surgery. The treatment is anti-coagulation for 3-6 months.
A blood clot that breaks-off and travels to the lungs is called a Pulmonary Embolus. This is a rare but life threatening complication. The treatment is anti-coagulation for 3-6 months.
STIFFNESS
It requires hard work after knee replacement surgery to achieve the maximum possible range of movement. Occasionally the knee can become stiff due to excess scar formation (Arthrofibrosis). This may require later surgery to excise the deep scar tissue.
LOOSENING
The new knee joint is initially a press-fit or cement grout onto the bones. Over a period of years the bone-implant interface may breakdown leading to loosening of the knee replacement. Often this is associated with increased wear of the polyethylene insert, which sits between the metal implants to allow movement. A loose knee replacement may need revision surgery to replace the components.
GENERAL COMPLICATIONS
WOUND HEALING
All knee replacements are performed through open incisions in front of the knee. The first priority after surgery is to ensure the wounds heal adequately. Delayed wound healing is sometimes seen in patients with systemic diseases such as Rheumatoid Arthritis or inpatients that have been taking Steroids for any reason.
HAEMARTHROSIS
Bleeding within the knee joint can complicate any surgical procedure. A haemarthrosis will usually respond to ice, rest and physiotherapy but can lead to delayed recovery and joint stiffness.
NERVE INJURY
Small areas of numbness may be associated with the operative incisions. The numbness is usually temporary. Occasionally wounds can become painfully sensitive, although this normally settles with time.
REFLEX SYMPATHETIC DYSTROHY
Reflex Sympathetic dystrophy is a little understood condition, which can complicate any operation. It consists of regional pain, swelling, sweating and stiffness due to local overactivity of the sympathetic nerves triggered by surgery, however minor.