Preventing osteoporosis-related fragility fractures after knee or hip replacement
April 20, 2022
About 10 million people in the U.S. have osteoporosis, a disease that slows the growth of healthy bones over time. It affects nearly 20% of women age 50 and older, and can increase the risk of a fragility fracture during or after joint replacement surgery – with falling being the most common culprit.
In a joint replacement procedure, we replace a worn hip or knee joint with an implant made of body-safe metal. For most patients, the bones on either side of the implant grow onto it over time or are fused to the joint with a cement-like compound. However, osteoporosis weakens the bones, which can result in poor or no grafting of surrounding bone to the implant. Fragility fractures can also occur during surgery if the surrounding bone is too brittle to withstand surgical cutting or manipulation.
If a patient with osteoporosis falls after having a knee or hip replacement – even several years after surgery – the weakened bones near their implant can easily break.
Fragility fractures can cause immobility, intense pain, and an increased risk of complications such as infection or death. Most patients need an urgent revisional surgery, which is complex and should only be done by experienced specialists.
UT Southwestern’s orthopedic surgeons specialize in primary and revisional joint replacement procedures. We perform hundreds of hip and knee procedures each year, and our surgeons help set national standards for patient outcomes after joint revision and replacement. Many patients come to us for revisional surgeries after inadequate surgeries performed elsewhere.
When our patients also have osteoporosis, we collaborate with the UT Southwestern bone mineral metabolism team to reduce the risk of broken bones. These experts specialize in bone degeneration conditions and will co-manage your care before surgery and after, particularly if you suffer a fall-related fracture.
Approximately half of all women and a quarter of men will suffer a fragility fracture in their lifetime. While common, osteoporosis-related fractures after joint replacement often can be prevented.
Patients with osteoporosis who want a knee and hip replacement should understand their personal risks – and start preparing before surgery to prevent or reduce the chances of fall-related fractures.
Osteoporosis risk factors for knee and hip replacement
Fragility fractures are slightly more common after total hip arthroplasty compared to total knee arthroplasty.
- Total knee replacement (TKR) is more common than partial replacement.
- Orthopedic surgeons are more likely to use medical cement in a knee replacement. Knee implants weigh 1-2 lbs., and the surrounding bone might have trouble holding the implant in place if the bone is too brittle. This may lead to loosening of the implant from the bone. Medical cement provides stability and reduces the risk of having a loose joint.
However, the risk of fragility fracture is never zero. Patients with osteoporosis should be cautious after knee replacement surgery, even if their implant is cemented in place.
Hip joints are larger and surrounded by sturdier weight-bearing muscles in the thighs, core, and lower back. Many hip replacements are partial, meaning a portion of the existing, healthy joint is left intact. Total hip replacement implants weigh 1-3 lbs., which is a little less than the natural bone. Patients who had a fragility fracture within three years before a total hip replacement are more likely to experience a break during surgery, according to research. Orthopedic surgeons are less likely to use cement in total hip replacements. With hip replacement, patients typically have better outcomes when their bones properly graft to the implant. Using cement lengthens the surgery, which requires more time under anesthesia. That can increase the risk of cognitive or physical complications in older patients and those with underlying medical conditions.
If you have osteoporosis, talk with your surgeon about your risks and whether they should consider cementing the implant – it may be the best choice to reduce your risk of fracture, depending on your bone health.
Related reading callout: After the fall: RESTORE bone health and prevent future hip fractures in seniors
Tips to avoid falling after joint replacement surgery
All patients – with or without osteoporosis – must take precautions to avoid falling after knee or hip replacement surgery. Moving will be painful those first few weeks, and it takes a while to gain balance and confidence in walking with a new joint. Osteoporosis compounds the risks of falling.
Whereas a fall might result in bruising for a patient with strong bones, it can cause a severe fracture in a patient with brittle bones.
Particularly for patients with osteoporosis, we recommend taking these precautions prior to joint replacement surgery to reduce your risk of suffering a fragility fracture:
- Start taking vitamin D and calcium supplements: Vitamin D helps your body absorb calcium and phosphorus – both of which help build new bones and maintain bone health.
- Discuss other osteoporosis drugs with your doctor: Some patients benefit from medications that alter the natural cycle of bone breakdown and growth, such as ibandronate (brand name Boniva). These drugs can help improve your bone mineral density, resulting in stronger bones.
- Do bone-loading exercises: Stressing the bones through weight-bearing exercise, within reason, can spur action in the cells that build new bones.
- Fall-proof your home: Modify what you can to reduce the risk of tripping, particularly at night. Remove loose rugs or tape down their ends prior to surgery. Install nightlights along your route from the bedroom to the bathroom and relocate items that usually live on the floor (such as hampers, baskets, or storage containers).
- Plan for your pets: Cats and dogs have a knack for winding up underfoot. Put a bell on their collars and consider kenneling or using a pet daycare for the first few weeks of recovery. Ask for help walking your dog for the first few months after joint surgery to avoid tripping or falling, even with the most well-behaved pets.
- Use an ambulatory device: Your doctor likely will recommend using a cane or walker during recovery to help you acclimate to bearing weight on the new joint. Don’t be too stubborn or proud; using a walker or cane can facilitate a safer recovery.
- Wear well-fitting shoes: At home or out and about, wearing sturdy shoes can help you maintain balance and avoid slipping or tripping.
- Temporarily modify the bathroom: Standing, sitting, and stepping high will be challenging for a few months – and these necessary movements carry a risk of falling. Install grab bars or handrails around the tub, shower, and toilet to help you use the facilities safely during recovery.
Despite efforts to reduce fractures, more than 300,000 people age 65 and older in the U.S. are hospitalized for broken hips each year – approximately 95% of these injuries are from falling.
Related reading callout: Why hip fractures require immediate treatment
What happens if I suffer a fragility fracture?
If you break a bone after knee or hip replacement, you will likely need an urgent revision surgery to prevent further, serious complications. UT Southwestern has developed a unique program to connect seniors who fall with advanced orthopedic care.
If a senior presents to our emergency department with a fragility fracture, they are automatically enrolled in the Returning Seniors to Orthopedic Excellence (RESTORE) program, the first of its kind in North Texas. Through RESTORE, we expedite emergency department care, which will include a consultation with our geriatric and orthopedic teams.
RESTORE patients receive non-narcotic pain medication to reduce delirium – confusion and agitation associated with surgery after a traumatic injury in seniors. After surgery, our experts will meet with you to discuss nutritional and lifestyle modifications and schedule a follow-up visit to help prevent future fractures.
If you have osteoporosis and want a joint replacement procedure, talk with your doctor about options to improve your bone strength before and after surgery. With planning and specialized care, you can reduce your risk of a serious fragility fracture and enjoy the freedom of restored mobility that knee or hip replacement can bring.
To talk with an osteoporosis or hip replacement expert, call 214-645-8300 or request an appointment online.