Hello, this is attorney Oh Seung-hyun of Cheongchul Law Firm.

Spinal surgery for disc herniation, spinal stenosis or cervical cord compression is high-risk treatment that bears directly on quality of life. When unexpected paralysis, nerve damage or sensory disturbance appears afterwards, patients naturally ask: "Is this an unavoidable complication, or a mistake by the surgeon?"

Korean courts do actively find medical negligence for nerve injury after spinal surgery where certain conditions are met. This article examines the courts' test and how damages are calculated, based on actual decisions.

Complication or negligence — how do the courts distinguish?

The risk of surgery is not the same as breach of duty

Spinal surgery is performed adjacent to nerve tissue, so the mere possibility of complications is not treated as negligence. The courts ask whether the duty of care required at the prevailing standard of medical practice was discharged. Where surgery was performed in accordance with current techniques and medical guidelines and an unforeseeable outcome followed, that is an "unavoidable complication" rather than negligence.

Presuming negligence — comparing symptoms before and after surgery

Direct proof of negligence is very difficult for a patient. Korean courts therefore presume negligence where:

• symptoms absent before surgery (paralysis, sensory disturbance) appear immediately afterwards;

• those symptoms are unlikely to have arisen from any cause other than the surgery; or

• the operative record states "no abnormality" although a complication in fact occurred.

The Supreme Court's position is that, given the special character of medical treatment, the patient's burden of proof is eased, and where an outcome occurs that is hard to accept by ordinary standards, the medical team must prove the absence of negligence.

Key decisions on spinal surgery negligence

Delayed treatment of a haematoma causing permanent cauda equina syndrome — Busan District Court Western Branch 2018Gahap102657

A 63-year-old woman underwent posterior decompression of the thoracolumbar spine and posterior decompression and fusion of the lumbosacral spine for spinal stenosis. She reported reduced strength in the right leg and bladder and bowel dysfunction immediately after the first operation, but the surgeon did not perform an MRI until 12 days later and, having identified a haematoma, waited more than 24 hours before carrying out emergency evacuation.

The court (judgment of 28 May 2020) found negligent delay and held the hospital responsible for the permanent worsening of cauda equina syndrome. Where new neurological symptoms appear after spinal surgery, an MRI must be performed immediately and decompression carried out promptly; the delay of more than 12 days was the core of the negligence. Liability was limited to 20%, and damages of approximately KRW 143.43 million were awarded.

Dural injury, delayed treatment and breach of the duty to explain — Changwon District Court Tongyeong Branch 2014Gadan8256

A male patient underwent revision surgery for an L4-5 disc. The dura was damaged during surgery with leakage of cerebrospinal fluid (technical negligence), and despite continuing pain and bleeding an epidural blood patch was delayed by 13 days. Consent to surgery was obtained only from the patient's child rather than the patient, breaching the duty to explain.

The court (judgment of 8 February 2017, upheld on appeal in 2017Na51676) found all three failures and awarded approximately KRW 56.8 million subject to a 40% limitation of liability. That revision surgery involves greater adhesion and difficulty than a first operation was taken into account in limiting liability.

Defective screw fixation causing permanent foot drop — Suwon District Court Pyeongtaek Branch 2022Gadan53370

A 53-year-old man underwent L3-4 interbody fusion with screw fixation. Four months later the screws loosened, and the resulting nerve root and peroneal nerve injury left permanent lower limb impairment including foot drop.

The court (judgment of 26 November 2025) found technical negligence in the screw fixation. With liability limited to 80% (reflecting the patient's pre-existing degenerative changes), damages of approximately KRW 24.45 million were awarded. Loosening within a relatively short period after surgery was itself treated as clear evidence of defective fixation.

Technical negligence in cervical disc replacement and failure to use neuromonitoring — Uijeongbu District Court 2015Gahap50771

A 53-year-old woman developed incomplete quadriplegia immediately after C4-5 artificial disc replacement and required emergency posterior cervical decompression and anterior corpectomy and fusion. The instrument had been inserted excessively deeply during the first operation, and no intraoperative neuromonitoring device was fitted.

The court (judgment of 27 June 2018) found technical negligence, failure to use monitoring, and breach of the duty to explain. Subject to an 80% limitation of liability, it awarded approximately KRW 125.3 million in pecuniary loss plus KRW 20 million in consolation money, some KRW 145.3 million in total. The decision became final when the Supreme Court dismissed the appeal without further review.

Technical negligence in anterior cervical surgery, dural rupture and no monitoring — Cheongju District Court Jecheon Branch 2017Gahap10056

A man in his early sixties underwent C3-4 and C4-5 anterior discectomy and corpectomy with fusion for cervical myelopathy, disc herniation and ossification of the posterior longitudinal ligament. The spinal cord was directly injured during surgery, the dura ruptured with leakage of cerebrospinal fluid, and further nerve injury occurred during insertion of the bone graft. Failure to use neuromonitoring was also found negligent.

The court (judgment of 25 January 2018) applied a 40% limitation of liability (reflecting the pre-existing ossification and degenerative changes and the difficulty of the surgery) for right-sided hemiplegia and lower limb paralysis immediately after surgery, later fixed as permanent incomplete quadriplegia, and awarded approximately KRW 140.85 million.

Cauda equina syndrome after lumbar discectomy — Supreme Court 2022Da303995

Where cauda equina syndrome developed after L4-5 discectomy, the Supreme Court (judgment of 31 August 2023) found medical negligence but limited the hospital's liability to 60% in light of the patient's pre-existing conditions (disc herniation and spinal stenosis). The decision established the important principle that impairment that would inevitably have occurred even without the wrongful act must be excluded from the calculation of loss of earning capacity.

Five types of negligence the courts have recognised

• (i) Technical negligence: direct injury to nerves or spinal cord, excessive insertion of instruments, defective screw fixation

• (ii) Dural injury: rupture of the dura causing leakage of cerebrospinal fluid

• (iii) Delayed postoperative treatment: failure to relieve haematoma or nerve compression promptly

• (iv) Failure to use neuromonitoring: breach of the duty to monitor nerve function in real time

• (v) Breach of the duty to explain: failure to explain the risks of surgery adequately to the patient

Calculating damages and limiting liability

Contribution of pre-existing conditions and deduction of inevitable impairment

Spinal disease is usually already progressing before surgery. The courts deduct the proportion of the present impairment attributable to pre-existing conditions before calculating damages. Under Supreme Court Decision 2022Da303995, impairment that would inevitably have resulted from the progression of pre-existing disease even absent negligence is excluded from loss of earning capacity.

Summary of liability limits and awards

• Busan Western Branch 2018Gahap102657: delayed haematoma treatment → 20% liability, approx. KRW 143.43 million

• Changwon Tongyeong Branch 2014Gadan8256: dural injury, delay, duty to explain → 40%, approx. KRW 56.8 million

• Suwon Pyeongtaek Branch 2022Gadan53370: defective screw fixation → 80%, approx. KRW 24.45 million

• Uijeongbu District Court 2015Gahap50771: technical negligence and no monitoring → 80%, approx. KRW 145.3 million (final)

• Cheongju Jecheon Branch 2017Gahap10056: technical negligence, dural rupture, no monitoring → 40%, approx. KRW 140.85 million

• Supreme Court 2022Da303995: cauda equina syndrome after discectomy → 60%, approx. KRW 122.77 million (lower court)

Liability limits in spinal surgery cases therefore range widely from 20% to 80%, and final awards vary from tens of millions to well over KRW 100 million. The seriousness of the negligence, the patient's pre-existing conditions, the difficulty of the surgery and the medical team's subsequent response all affect the ratio.

How to respond if you are affected

Step 1. Secure the medical records immediately

Request all records — operative notes, anaesthetic records, nursing records and imaging — from immediately after surgery. A medical institution cannot refuse a patient's request to inspect or copy them (Article 21 of the Medical Service Act). Operative notes and pre- and post-operative MRI and CT images are the core evidence of negligence. As the case law shows, where operative records do not match reality, the courts apply presumptions strongly adverse to the medical team.

Step 2. Record how the symptoms developed

Keep a dated record of when each symptom appeared and what the medical team said. Whether symptoms appeared immediately after surgery, and whether the team acted at once, is decisive on delayed treatment.

Step 3. Choose between mediation and civil litigation

Where the evidence is clear and the sum modest, the Korea Medical Dispute Mediation and Arbitration Agency offers a faster route. Severe impairment or complex disputes require civil litigation. In both, representation by a lawyer experienced in medical cases materially affects the outcome.

Step 4. Consider a parallel criminal complaint

Where there are grounds to suspect an offence such as false entries in operative records, a criminal complaint may be filed in parallel. Evidence obtained in the criminal investigation can be used in the civil case, and a combined strategy is often effective.

In closing

If unexpected paralysis or nerve damage follows spinal or joint surgery, have it assessed legally to determine whether it is a complication or negligence. Courts recognise a range of failures — delayed treatment of haematoma, technical negligence, failure to use neuromonitoring, breach of the duty to explain — and where liability is established, awards range from tens of millions to over KRW 100 million.

Cheongchul Law Firm has a dedicated medical negligence team handling spinal and cervical surgery negligence, breach of the duty to explain and other medical disputes. If you suspect harm from spinal or joint surgery, please contact us for a consultation.

Thank you.