ConditionBones, joints & muscles
Spinal Hardware Problems After Spine Surgery
Spinal hardware problems are complications involving the screws, rods, plates, cages or other implants used in spine surgery, usually spinal fusion. They include loosening, breakage, movement out of position, infection, irritation of nearby tissues, and failure of the bones to fuse (pseudarthrosis). Many cause no symptoms and are found on follow-up X-rays. Others cause new or returning back or neck pain, nerve symptoms or signs of infection. Treatment ranges from monitoring to revision surgery.
Also called: Instrumentation failure, implant complications, spinal hardware failure, loose pedicle screws, broken spinal rod, hardware-related pain
At a glance
- What it is
- Problems with implants used to stabilize the spine, or with the fusion they support.
- Types
- Screw loosening, rod or screw breakage, implant migration, infection, painful prominent hardware, nonunion.
- Risk factors
- Osteoporosis, smoking, diabetes, obesity, long fusions, early heavy activity.
- Symptoms
- None, or new or recurring pain, nerve symptoms, a prominent lump, wound drainage or fever.
- Diagnosis
- X-rays (including flexion-extension views), CT scan, blood tests for infection.
- Treatment
- Observation, bracing, bone stimulators, antibiotics, or revision surgery.
When to get help
Call 911 or go to the ER
- New leg weakness, numbness in the saddle area, or loss of bladder or bowel control after spine surgery
- High fever, chills and confusion after spine surgery
See a doctor within a day or two
- Wound redness, swelling, drainage or opening at any time after surgery, with or without fever
- Sudden new back or neck pain, a popping sensation, or new nerve pain down a limb after surgery
- Fever above 38 °C (100.4 °F) in the weeks after surgery
Book a routine appointment
- Back or neck pain returning months to years after fusion
- A tender lump over the hardware, or pain lying on the area
- Clicking or a feeling of movement in the fused area
- Follow-up X-rays as scheduled by your surgeon, even if you feel well
How spinal hardware works
In spinal fusion, the surgeon joins two or more vertebrae so that they heal into one solid bone. Bone graft is placed between the vertebrae, and hardware such as pedicle screws and rods, plates or interbody cages holds them still while the bone grows together. Fusion usually takes 6 to 12 months. Once fused, the bone carries the load and the hardware becomes less important.
If fusion does not happen, the hardware keeps bearing stress and can eventually loosen or break, much like a paper clip bent repeatedly.
Types of hardware problems
| Problem | What happens | Typical clues |
|---|---|---|
| Screw loosening | A "halo" of bone loss around a screw on X-ray or CT | Often silent; may accompany nonunion |
| Rod or screw breakage | Metal fatigue from repeated stress | Sudden pain or a pop; usually means the fusion has not healed |
| Pseudarthrosis (nonunion) | Bones fail to fuse | Pain returning after initial improvement |
| Implant migration | A cage or screw shifts | New nerve pain, or rarely damage to nearby structures |
| Infection | Bacteria on the hardware | Wound drainage, fever, increasing pain, early or late |
| Painful prominent hardware | Implants felt under the skin, especially in thin people | Tender lump, pain lying on the back |
| Adjacent segment disease | Wear in the levels above or below the fusion | New pain or stenosis symptoms years later |
Risk factors
- Osteoporosis: weak bone holds screws poorly.
- Smoking and nicotine: strongly reduce fusion rates.
- Diabetes, obesity and poor nutrition.
- Long fusions, fusions crossing to the pelvis, and revision surgery.
- Steroid use and some other medicines.
- Heavy activity or bending too early after surgery.
- Scoliosis and deformity surgery, with higher mechanical stress.
Symptoms
Hardware problems can be silent. When symptoms occur:
- new, persistent or returning back or neck pain after a period of improvement
- leg or arm pain, numbness or weakness from nerve irritation
- a tender lump over the surgical site
- clicking or grinding
- wound drainage, redness, swelling or fever with infection
Diagnosis
- X-rays, including bending (flexion-extension) views, show alignment, broken implants, lucency around screws and motion at the fusion.
- CT scan: the best test for confirming fusion and detecting loosening.
- MRI: for nerve compression; modern implants are usually MRI-safe, though metal can blur images.
- Blood tests: white cell count, ESR and CRP if infection is suspected.
- Image-guided aspiration or biopsy to identify bacteria.
- Diagnostic injections around prominent hardware to see if it is the pain source.
Treatment
- Observation: asymptomatic loosening or a single broken screw with a solid fusion often needs no treatment, just monitoring.
- Bracing and activity changes to reduce stress while fusion progresses.
- Bone growth stimulators in some cases of delayed fusion.
- Treat bone health: osteoporosis medicines such as teriparatide may support fusion in people with weak bones.
- Stop smoking.
- Infection: early infections may be treated with surgical washout and antibiotics while keeping the hardware; late infections may require hardware removal once fusion is solid.
- Hardware removal: for painful prominent implants, after the fusion has healed.
- Revision surgery: for symptomatic nonunion, broken hardware, migration, nerve compression or adjacent segment disease. This may involve new screws, additional rods, extended fusion or a different approach.
Outlook
Many hardware problems found on scans cause no symptoms and never need treatment. When revision is required, outcomes are generally good when the cause, such as nonunion or infection, is identified and addressed, though recovery is often longer than after the first operation.
Frequently asked questions
What are signs of hardware failure after spinal fusion?
Signs include back or neck pain that returns after initial improvement, a sudden pop with new pain, new leg or arm nerve symptoms, clicking at the surgical site, and wound problems or fever with infection. Many failures are found only on X-ray or CT.
Is a broken screw after spinal fusion serious?
Not always. If the bones have fused solidly, a broken screw may cause no problems and can be watched. If it reflects a failed fusion, or causes pain or nerve symptoms, revision surgery may be needed.
Can spinal hardware be removed?
Yes, once the fusion is solid, hardware can be removed if it causes pain or infection. Removal before fusion is complete risks loss of correction or instability, so surgeons confirm fusion with a CT scan first.
How can I reduce the risk of hardware problems?
Stop smoking before and after surgery, manage diabetes, treat osteoporosis, eat well, follow activity restrictions during healing, and attend follow-up appointments and X-rays so problems are spotted early.
Sources
This guide was written from current patient and clinical guidance, including:
- American Academy of Orthopaedic Surgeons (OrthoInfo): Spinal fusion
- North American Spine Society: Patient education on spinal fusion
- American Association of Neurological Surgeons: Spinal fusion
- MedlinePlus: Spinal fusion
- Scoliosis Research Society: Adult scoliosis surgery complications