Spinal Fusion and Instrumentation Surgery Negligence Claims

What “instrumentation” means in spinal fusion

In the context of spinal surgery, “instrumentation” refers to the medical devices implanted into your spine to provide stability.

Think of a spinal fusion like setting a broken bone in a cast. The goal is for the two vertebrae to grow together into one solid bone (the fusion). However, bone takes months to heal. Instrumentation acts as an internal cast or scaffolding. It holds the vertebrae rigidly in place so the biological fusion can occur. Once the bone fuses, the metalwork essentially becomes redundant, though it is rarely removed unless it causes problems.

Common implant types

Different spinal conditions require different types of hardware. Understanding what was placed in your back is the first step in understanding potential complications.

• Pedicle Screws: These are metal screws implanted into the pedicle (a dense stem of bone on the vertebra). They act as strong anchor points.
• Rods: Metal rods connect the screws together, bridging the gap between vertebrae to prevent movement.
• Cages (Interbody Devices): These are hollow, spacer-like devices placed between vertebrae (where the disc used to be). They restore height to the spine and are packed with bone graft to encourage growth.
• Plates: Often used in the cervical spine (neck), these are screwed into the front of the vertebrae to provide stability.
• Bone Graft and Biologics: This is the material that creates the actual fusion. It can be your own bone (autograft), donor bone (allograft), or synthetic bone substitutes.

What can go wrong in spinal fusion and instrumentation surgery

Spinal surgery carries inherent risks, and not every poor outcome is due to negligence. However, specific complications can arise if the standard of care falls below what is expected of a competent spinal surgeon.

Pre-operative assessment and planning issues

Success starts before the patient enters the operating theatre. A surgeon must ensure the operation is actually necessary and that the correct approach is chosen.

• Failure of conservative management: Usually, surgery should only be offered after physiotherapy and pain management have been exhausted (unless there is urgent nerve danger).
• Radiological planning: The surgeon must study MRIs and CT scans to measure the pedicles and plan the screw trajectory. Failure to plan for the patient's specific anatomy can lead to intra-operative errors.
• Assessment of bone density: If a patient has osteoporosis, standard screws may not hold. Failure to account for poor bone quality can lead to early hardware failure.

Wrong level or wrong side surgery

This is categorised as a "Never Event" in medicine,an error that is entirely preventable and should simply not happen.

• This occurs if the surgeon operates on, for example, the L3/L4 level when the problem was at L4/L5.
• It can happen due to a failure to count the vertebrae correctly under X-ray guidance in the theatre.
• The result is that the patient undergoes the trauma of surgery, the healthy level is fused unnecessarily, and the painful level remains untreated.

Pedicle screw or implant positioning problems

Placement of pedicle screws requires high precision. The screw must stay entirely within the bone.

• Medial Breach: If the screw is angled too far inward, it can break through the bone and enter the spinal canal, pressing on the spinal cord or nerves.
• Lateral Breach: If angled too far outward, it may endanger blood vessels or other structures.
• Anterior Breach: If the screw is too long, it can poke out the front of the spine, potentially damaging major blood vessels like the aorta or iliac veins.

Negligence may arise if the surgeon fails to recognise a malpositioned screw on intra-operative X-rays or fails to correct it immediately.

Nerve root injury, spinal cord injury, and dural tear/CSF leak

Spinal fusion involves working just millimetres away from the spinal cord and the nerves that control your movement and sensation. When surgical instruments or implants interfere with these delicate structures, three primary types of injury can occur: leaks from the protective spinal fluid sack, direct damage to specific nerve roots, or critical pressure on the nerve bundle at the base of the spine.

• Dural Tear (Leaking Fluid): The spinal cord sits inside a watertight sack of fluid. If this sack is nicked during surgery and not spotted or fixed, spinal fluid can leak out. This often causes severe headaches that are worse when standing up, or fluid leaking directly from the wound.
• Nerve Root Injury: If a nerve is accidentally pinched or cut during the procedure, it disrupts the signals going to your leg. This can result in weakness (such as a "foot drop" where you cannot lift your foot), permanent numbness, or ongoing shooting pain.
• Cauda Equina Syndrome: This is a rare but critical emergency where a blood clot or severe swelling crushes the bundle of nerves at the very bottom of the spine. If this pressure is not relieved immediately by further surgery, it can cause permanent loss of bladder and bowel control.

Bleeding and pressure on the spinal cord

After surgery, it is possible for blood to collect at the operation site, forming a clot (haematoma). While some bleeding is normal, a large clot can accumulate rapidly and press against the spinal cord.

This is a critical situation. If the pressure is not relieved, it can cause permanent paralysis. The warning signs are usually clear: a sudden loss of strength in the legs or a loss of sensation when going to the toilet. If nursing staff or doctors dismiss these signs or delay returning you to theatre to remove the clot, the standard of care may have been breached.

Infection and issues with metalwork

Infections in spinal surgery are particularly complex because bacteria can "hide" on the surface of the metal implants, making them resistant to standard antibiotics.

• Surface infections generally affect only the skin and wound line.
• Deep infections reach the muscle and the hardware itself.

A deep infection is serious. It often requires further surgery to wash out the wound. In the worst cases, the surgeon may have to remove the screws and rods entirely to clear the infection. If this happens before the bone has fully healed, the fusion may fail. We investigate whether sterile procedures were followed in the operating theatre and if the medical team reacted quickly enough when the wound first looked red or leaked fluid.

Failure to fuse (Non-union)

The goal of the surgery is for the vertebrae to grow together into one solid bone. If this does not happen, it is called non-union (or pseudoarthrosis).

When the bone fails to fuse, the metal screws and rods continue to bear all the weight of your spine. Metal cannot withstand this stress forever; eventually, like a paperclip bent back and forth, the rods will snap or the screws will loosen. While some patients (such as smokers) are at higher risk, surgical technique is often a factor. We look at whether the surgeon properly prepared the bone and used enough bone graft to give the fusion the best chance of success.

Hardware loosening and breakage

Even if the surgery initially goes well, mechanical issues can arise later if the construct was not planned correctly.

• Screw pull-out: The screws may lose their grip and back out of the bone.
• Rod breakage: The metal rods may snap due to ongoing stress.
• Cage migration: The spacer placed between the vertebrae can slip out of position, potentially pressing on nerves.

There is also a risk of "Adjacent Segment Disease." This happens when the fused part of the spine is too stiff or fixed in a poor position, placing excessive strain on the discs directly above and below the surgery. If the surgeon fixed the spine in an unnatural curve, this wear and tear can happen much faster than expected.

Delays in monitoring and reacting

The hours immediately after you wake up from anaesthesia are vital. Nurses and doctors must perform regular checks on your foot movement and sensation to ensure your nerves are functioning.

Time is critical here. If you tell a nurse that your foot feels weak or numb, and the medical team waits hours before calling a consultant or ordering a scan, that delay can be devastating. A complication that could have been fixed with quick action can become permanent injury if ignored for too long.

Symptoms after spinal fusion: expected recovery vs warning signs

It is difficult for patients to know what is "normal" post-operative pain and what is a sign of a complication.

If you experience the following, it warrants investigation:

• New weakness: For example, being unable to lift your big toe or foot (foot drop) that wasn't present before surgery.
• Escalating leg or arm pain: Shooting electrical pain that is worse than pre-surgery.
• Wound changes: Redness, heat, swelling, or fluid leaking from the dressing.
• Fever/Chills: A sign of systemic infection.

If you experience these, you must seek emergency care immediately:

• Loss of bowel or bladder control: Inability to pass urine or incontinence.
• Saddle anaesthesia: Numbness in the groin/genital area or buttocks.
• Severe headache: Specifically a headache that is worse when standing and better when lying flat (sign of a CSF leak).

How problems are investigated and diagnosed

When we investigate a claim, we look at how the medical team investigated your complications.

Examination and neurological assessment

The first step is a clinical exam. A doctor should test reflexes, muscle power (graded 0 to 5), and sensation. Poor record-keeping here is common. If the notes say "moving all limbs" but the patient had a profound foot drop, the records are inaccurate.

Imaging pathways: X-ray, CT, MRI and what each is used for

Different scans show different things.

• X-Ray: Good for a quick check of overall alignment and seeing if a screw has obviously snapped.
• CT Scan: The "Gold Standard" for bone. This is the best way to see if a screw has breached the bone or if fusion has occurred.
• MRI (with metal artefact reduction): Best for soft tissue. It shows if a nerve is being compressed or if there is fluid/infection. Note: Metal implants can distort MRI images, so special sequences are needed.

Infection work-up and follow-up planning

If infection is suspected, blood tests (CRP and White Cell Count) are vital. A sample of fluid from the wound should be sent to the lab before antibiotics are started blindly, so the specific bacteria can be identified.

Revision surgery decision-making

If hardware is misplaced or infection is deep, revision surgery is often discussed. This is a complex decision. We investigate whether the revision was required due to an initial error, or if the revision itself was delayed unnecessarily, causing further harm.

When a poor outcome may raise questions about the standard of care

In Irish medical negligence law, a bad outcome does not automatically mean negligence occurred. We must prove a breach of duty.

• Consent and discussion of material risks and alternatives: Did you truly understand the risks?
  • The surgeon has a duty to warn you of material risks,risks that would influence your decision to go ahead.
  • If you were told surgery was "simple" and "guaranteed to work," and were not warned about nerve damage or instrument failure, your consent may not have been valid.
• Intra-operative safeguards:
  • Imaging Checks: Did the surgeon use fluoroscopy (live X-ray) or O-arm navigation to check screw placement during the surgery?
  • Neuromonitoring: In complex cases, electrical leads are placed on the legs to monitor nerve function during surgery. If the nerves signalled distress and the surgeon ignored this, it may be negligence.

• Sterile technique and infection prevention steps: Hospitals have strict protocols for antibiotics before the skin is cut and for sterile preparation. A breach in these protocols leading to a deep spinal infection can be the basis of a claim.

• Discharge planning and follow-up: Being sent home too early, or without a plan for managing complications, is a common issue. If you called the hospital complaining of leaking fluid or severe pain and were told "it's normal" without being seen, and this led to a delay in treatment, the standard of care may have been breached.

Evidence and records commonly relevant in instrumentation cases

Building a case requires a forensic examination of your medical file.

• Operative note, implant log, device identifiers, theatre records: We obtain the handwritten or typed operation note. We compare this against the nursing count records and the implant log stickers. Discrepancies here can be telling.
• Radiology before and after surgery: We will request all your scans on disc. Our independent experts will compare the pre-op anatomy with the post-op hardware placement. The timing of these scans is crucial,was a CT scan ordered immediately when you reported pain, or was it delayed by weeks?
• Neuromonitoring records (where used): These computer-generated logs show the electrical activity of your nerves throughout the surgery. They provide an objective timeline of when nerve distress occurred.
• GP and hospital re-attendance records: Your GP records often tell the story of the recovery,visits for pain medication, antibiotics for wound issues, or referrals to physiotherapy.
• Independent expert review and causation analysis: We do not rely on guesswork. We instruct independent spinal surgeons (usually from the UK) to review your files. They will provide an opinion on:
  • Breach of Duty: Did the care fall below the acceptable standard?
  • Causation: Did that specific error cause your current injury (as opposed to your underlying back condition)?

Making spinal fusion and instrumentation surgery negligence claims in Ireland

Navigating the legal landscape in Ireland requires specialist knowledge. We guide you through the process, explaining exactly what is required to build a successful case.

The legal test for negligence

A poor surgical outcome does not automatically mean there has been negligence. To succeed in a claim, we must prove four specific elements. Firstly, we must show that the medical team owed you a duty of care (which is automatic in a doctor-patient relationship). Secondly, we must prove a breach of duty,that the surgeon failed to meet the standard of care expected of a reasonably competent spinal specialist. Thirdly, we must establish causation, meaning that this specific failure directly caused your injury. Finally, we must demonstrate that you have suffered damages (pain, suffering, or financial loss) as a result.

Time limits and the “date of knowledge”

Generally, the Statute of Limitations for medical negligence in Ireland is two years from the date of the injury. However, spinal instrumentation cases often rely on the "Date of Knowledge." You might have had surgery in 2020 but only discovered in 2024,perhaps via a new X-ray,that a screw had broken or was misplaced. In these situations, the two-year clock may only start ticking from the date you found out (or ought to have known) about the error. This is a complex area of law, so it is vital to seek advice immediately to ensure you do not become statute-barred.

Who is responsible? Public vs. Private care

The path of your claim depends on where you were treated. For public patients (HSE), claims are usually handled by the State Claims Agency (SCA) under the Clinical Indemnity Scheme. In these cases, we sue the HSE rather than the doctor personally. For private patients, the process differs; we typically sue the consultant surgeon directly, as they are indemnified by a Medical Defence Organisation (such as the MDU or MPS).

The typical stages of a case

Bringing a claim is a structured process. It begins with us taking your instructions and listening to your full story. We then gather all relevant records, including your hospital notes and radiology scans. Once compiled, we send these to an independent expert for a screening report to get a preliminary view on whether negligence occurred.

If the evidence supports your case, we send a Letter of Claim to the defendants outlining the allegations. If they deny liability, we issue formal court proceedings. While this sounds daunting, it is important to note that the vast majority of cases settle before ever reaching a judge. However, we prepare every case with the rigour required for trial to ensure the best possible outcome.

Practical steps if you are concerned after spinal fusion surgery

If you fear something has gone wrong, your health is the priority.

• Medical assessment: Do not suffer in silence. If you are in pain, return to your surgeon or seek a second opinion from a different spinal specialist. Ensure you mention any "red flag" symptoms immediately.
• Keeping a timeline of symptoms and appointments: Memory fades, but a diary is strong evidence.
  • Write down dates of appointments.
  • Note what you were told ("Dr. X said the screw looked fine").
  • Record your pain levels and medication usage.
• Requesting records and imaging reports: You have a legal right to your medical records under GDPR and Freedom of Information acts. While we will do this for you formally, you are entitled to ask for a copy of your operation note and radiology reports at any time.

Frequently asked questions

How soon can complications show after spinal fusion?

Some are immediate (nerve injury during surgery), while others (like non-union or infection) can take weeks or months to present.

Can implant issues present months later?

Yes. Hardware failure (snapped rods/screws) usually happens months after surgery if the bone fails to fuse. The metal fatigues over time like a paperclip bent back and forth.

What records usually exist for screws, rods and cages used in surgery?

There should be an "Implant Log" or sticker sheet in your file detailing the manufacturer, batch number, and size of every single component used.

What if I was reassured but symptoms continued to worsen?

This is a common scenario. If you were falsely reassured and this led to a delay in diagnosing a treatable complication (like a misplaced screw or infection), this delay itself can form part of a negligence claim.

What is the time limit for clinical negligence in Ireland?

Strictly speaking, it is two years from the date of the injury or the date of knowledge. Do not delay seeking advice.

Does the Injuries Resolution Board deal with medical negligence?

No. The Injuries Resolution Board (formerly PIAB) does not assess medical negligence claims. These cases are managed through the litigation process.

We are here to help you find answers

Spinal fusion is meant to reduce pain, not create new suffering. If you believe your surgery involved errors in instrumentation, planning, or follow-up care, you need a legal team that understands the complex medicine behind the metalwork.

At Michael Boylan LLP, we specialise in complex medical negligence litigation. We approach every client with empathy and determination, ensuring you get the answers,and the justice,you deserve.

Contact us today for a confidential discussion about your experience.

*In contentious business, a solicitor may not calculate fees or other charges as a percentage or proportion of any award or settlement.