Names have been removed to protect privacy. Identifying letters are assigned in alphabetical order and bear no relationship to the person’s actual name.
On 16 July 2022, the Health and Disability Commissioner (HDC) received a complaint from Mr A regarding the care he received from Dr B at Health New Zealand | Te Whatu Ora Waikato (Health NZ Waikato). Mr A’s complaint concerns the management of spina bifida,1 specifically, that spinal cord detethering surgery2 on 18 November 2016 was performed at the wrong level of his back, that he was not fully informed pre- and postoperatively, and that he has concerns about his subsequent care. Mr A was aged 46 years at the time of the 2016 surgery. Mr A is now unable to walk and uses a wheelchair for mobility. I acknowledge the significant impact these events have had and continue to have on Mr A.
Information gathered
Mr A was born with spina bifida, but he told HDC that his condition did not greatly affect him until he reached his forties. Around this time, Mr A began to experience symptoms of tingling and pain in his feet and subsequent lower limb weakness. Mr A’s general practitioner (GP) referred him to a neurologist, who arranged further investigation by way of magnetic resonance imaging (MRI)3 scans on 22 April 2016. The MRI scans confirmed that Mr A’s spinal cord was tethered up to L54 with associated myelomeningocele.5
Mr A’s GP referred him to the neurosurgery team at Waikato Hospital. On 3 August 2016, he was seen by neurosurgeons Dr B and his registrar, Dr C, to discuss his symptoms, MRI results, and management options. Mr A’s symptoms of lower limb weakness, recent progressive weakness in the right lower limb, and reduced sensation in both feet were noted.
Mr A was offered surgery for lumbar laminectomy6 and detethering of the spinal cord. In his clinic letter dated 3 August 2016, Dr C recorded that there had been a ‘lengthy discussion’ regarding treatment options and that he had ‘emphasised to Mr A that the main purpose of the surgery is to prevent further deterioration of his symptoms, but it will not help with improving his pre-existing symptoms.’ Mr A was told that his right lower limb weakness may improve to a small extent after surgery. Dr C recorded that Mr A had been told that there was a 5% risk of nerve root damage, resulting in loss of bowel function and complete paraplegia. Dr C noted that Mr A appeared to have understood the potential benefits and risks of the procedure and that he had agreed to proceed. Mr A was subsequently placed on the urgent elective list for surgery.
Mr A’s case was reviewed at the Waikato Neurosurgical multidisciplinary team meeting (MDTM) on 11 August 2016. It was agreed that the lumbar laminectomy and detethering surgery should go ahead as Dr B and Dr C had discussed with Mr A during their appointment.
On 17 November 2016, Mr A was admitted to Waikato Hospital for lumbar laminectomy and detethering surgery. He signed a written surgical consent form7 that day, which listed the following risks: ‘Bleeding, infection, damage to nerves – continence, sexual function, numbness, wound leak, blood clots, risk to life.’ The consent form does not list paralysis as a potential risk. However, the typed operation note dated 18 November 2016 states under the section ‘Indications’ that ‘[Mr A] was adamant that he wanted surgery despite the risks of more weakness and paralysis, complete loss of bowel/bladder function. Consent was taken.’ Dr B also told HDC that he spoke to Mr A on the day of the surgery to again reiterate that ‘the risks of the surgery were high and that he might suffer from worsening neurological deficit in his legs …’. According to Dr B, Mr A acknowledged that his legs were already deteriorating and that he would like to proceed with the operation.
Mr A told HDC that he was reassured by Dr B on three separate occasions before the operation that his ability to walk would not be affected and that Dr B was confident with performing the surgery. Mr A also stated that he was told ‘there is a 5% chance that things may go wrong’.
On 18 November 2016, Dr B carried out the laminectomy and detethering procedure. The typed operation note says that an L5 laminectomy and detethering of the spinal cord was completed. It was noted that there was a lipoma8 and tethering of the spinal cord in the sacrum area.9 Dr B told HDC that he did not explore the lipoma to search for tethered cord in the sacrum area because ‘it would be easy to get lost and damage neural tissue.’ Dr B said that the decision to avoid the lipoma and release the cord higher was discussed with his colleagues at the MDTM on 11 August 2016. However, the MDTM note does not record this discussion.
Dr B said that the surgery went smoothly and that there was no drop in Mr A’s blood pressure to indicate damage to the spinal cord. However, Dr B told HDC that he unknowingly operated one level above where he intended to do the operation (L4 rather than L5). This was not discovered until an MRI scan was performed on 13 January 2017.
Following the procedure, Mr A experienced severe weakness in his lower limbs (paraplegia). Dr B told HDC that some deterioration was expected because of the detethering of the spinal cord, but he expected symptoms to improve quickly. Dr B also said he considered that the risk of postoperative compressive haematoma10 was very low, so he did not consider it necessary to order an MRI scan at that time. However, he accepted that completing an MRI scan at that time would have shown that he had operated at the wrong level, and he would have been able to inform Mr A of this sooner.
On 30 November 2016, Mr A was transferred to a public hospital for rehabilitation. Dr B noted that, at the time of discharge from Waikato Hospital, Mr A’s strength in both legs had improved such that it was similar to what was documented before the surgery.
On 13 January 2017, because Mr A’s recovery had been slow, an MRI of the lumbar spine was completed. The MRI showed that the operation had been completed one level higher than Dr B intended and that Mr A’s spinal cord had been transected (cut across) at L4.
Dr B told HDC that ‘[he has] never hidden the fact that [he] was at the wrong level and informed Mr A once the MRI scan confirmed this postoperatively and apologised.’ I am unable to find any record of such a conversation in the clinical documentation.
Mr A told HDC that Mr B ‘Never [came] clean on what really happened in surgery.’
Mr A continued to experience weakness and pain in his legs, as well as headaches. Further neurosurgical procedures were completed under the care of Dr B with the aim of addressing Mr A’s ongoing symptoms, including:
further spinal cord detethering surgery on 14 May 2019;
insertion of a lumbar drain11 on 5 February 2020 to relieve cerebrospinal fluid12 pressure on the pseudomeningocele;13
insertion of a ventriculoperitoneal shunt14 on 29 July 2020; and
insertion of a baclofen pump15 on 28 June 2021.
On 30 March 2023, further surgery (laminectomy, detethering of the spinal cord in the sacral region, reduction of subcutaneous lipoma, and removal of the baclofen pump) was completed by Dr E at a private hospital. Dr E stated that the surgery was indicated because of Mr A’s ongoing pain and discomfort, particularly at the site of the lipoma. Dr E also noted that Mr A had previously undergone two detethering operations, during one of which his spinal cord had been transected.
Mr A, Dr B, and Health NZ Waikato were provided with the provisional report for comment. Mr A said he would like Dr B to be held accountable, for him to learn from his errors, and for him to not repeat his mistakes on others. Mr A said he would also like Health NZ Waikato to take this incident seriously and ensure it is not repeated. Dr B said he accepted the report, and Health NZ Waikato said it had nothing further to add.
ACC information
On 22 November 2016, Waikato Hospital staff completed an ACC treatment injury claim on Mr A’s behalf. The claim stated that Mr A had experienced weakness in his legs following detethering of the spinal cord on 18 November 2016. The claim was made before the MRI on 13 January 2017 showed that the laminectomy had occurred at L4 instead of L5 – although this information was later provided to ACC.
ACC sought independent advice from an orthopaedic surgeon, and Dr Reuben Johnson, neurosurgeon.16
ACC’s independent advisor considered that transection of the spinal cord at L4 was an unexpected outcome of surgery and should be considered a treatment injury.
Dr Johnson agreed that transection of the spinal cord should be considered a treatment injury. In addition, he noted that transection of the spinal cord was not a necessary part of the laminectomy and detethering procedure that was performed. Dr Johnson stated that the failure to investigate Mr A’s severe and unexpected postoperative neurological deficit was below the expected standard of care. He also noted that Dr B appeared to have operated at the wrong level, which, if correct, was also outside the expected standard of care.
ACC concluded that transection of the spinal cord at L4 occurred during a L5 laminectomy and detethering procedure. This physical injury resulted in weakness in the lower legs and bilateral paralysis of the feet. Accordingly, ACC accepted that a treatment injury had occurred due to the transection.
Independent clinical advice
As part of this investigation, HDC sought independent clinical advice from Dr Johnson, neurosurgeon (Appendix A). He identified two departures from accepted standards in the care Dr B provided to Mr A.
While Dr Johnson considered that the overall consenting process was appropriate, he was critical that ‘paralysis’ and/or ‘paraplegia’ were not listed on Mr A’s written consent form for the 18 November 2016 operation. Dr Johnson considered that the risk of paralysis should be noted on the surgical consent form for any neurosurgical procedure on the spine. Dr Johnson considered the absence of this wording a moderate departure from accepted standards.
Dr Johnson considered that the decision to recommend detethering surgery for Mr A on 18 November 2016 was appropriate. However, he was critical that Mr B performed the operation at L4 rather than L5, indicating a failure to identify the correct level during the procedure. The operation being performed at the wrong level resulted in the severing of Mr A’s spinal cord above the level of tethering, and Dr Johnson considered that this was a severe departure from accepted standards of care. He also noted a failure to explore the lipoma in the sacral region during the operation.
Dr Johnson said that, for complex cases such as Mr A’s, it would be common, albeit not mandatory, practice to use intraoperative neurophysiology monitoring17 to assist with identifying neural structures and reducing the risk of spinal cord transection.
Dr Johnson also stated that it would have been appropriate for Dr B to request a postoperative MRI scan when Mr A showed neurological decline after the procedure on 18 November 2016. Dr Johnson considered that Mr A’s post-surgical decline was a rare and unexpected event. Investigative imaging would be used in such cases to establish the cause and rule out any reversible conditions, such as a compressive haematoma (although Dr Johnson acknowledges that this would be a highly unlikely occurrence). Dr Johnson also noted that a postoperative MRI scan would have identified the injury to Mr A’s spinal cord, leading to earlier communication to him regarding this error. Dr Johnson considered that Dr B’s failure to perform a postoperative MRI scan was a moderate departure.
Dr Johnson did not identify any departures from accepted practice in relation to Dr B’s immediate and subsequent postoperative care of Mr A after the surgery on 18 November 2016. This included the insertion of a ventriculoperitoneal shunt on 29 July 2020 and of a baclofen pump on 28 June 2021.
Opinion: Dr B
Operation and management of neurological decline – breach
Right 4(1) of the Code of Health and Disability Consumers’ Rights (the Code) states that every consumer has the right to have services provided with reasonable care and skill. Based on the available evidence, including the advice provided by Dr Johnson, it is evident that several aspects of Dr B’s care of Mr A did not meet accepted standards.
Dr Johnson was critical that the surgery of 18 November 2016 was performed at the wrong level, leading to the transection of Mr A’s spinal cord above the level that it was tethered. The fact that this error occurred indicates that Dr B did not correctly identify the level at which he was operating during the surgery, which was a departure from accepted standards of care. Dr B has accepted that he unknowingly operated at the wrong level. Accordingly, I accept Dr Johnson’s advice that Dr B operated at the wrong level, which was a severe departure from accepted standards.
Immediately following the detethering surgery, Mr A experienced neurological decline, with severe weakness in his legs. Dr Johnson considered that Mr A’s symptoms were an unexpected post-surgical outcome, that an MRI scan was indicated to investigate the cause and rule out a haematoma, and that failure to do so was a departure from expected standards of care. Dr B stated in his response to HDC that some neurological decline was expected post-surgery and that a haematoma was unlikely. However, Dr B acknowledged that an MRI scan would have identified that surgery had been completed at the wrong level, allowing Mr A to be informed of this error sooner. Noting Mr A’s significant neurological decline and the chance, albeit slight, of a haematoma, I consider it would have been appropriate for Dr B to have requested further investigation through a postoperative MRI scan. I accept Dr Johnson’s opinion that failure to request a postoperative MRI in such circumstances was a moderate departure from accepted standards.
Noting these two criticisms – operating at the wrong level of the spine and failing to request a postoperative MRI scan in the context of neurological decline – I consider that Dr B breached Right 4(1) of the Code.
Documentation – adverse comment
I note that the consent form Mr A signed before surgery did not list ‘paraplegia’ or ‘paralysis’ as a risk of the surgery. I accept Dr Johnson’s advice that consent forms for spinal procedures should list this risk. I acknowledge that Dr B’s registrar, Dr D, completed the consent form, but I consider that, as the lead clinician, Dr B held the overall responsibility for ensuring the adequacy of the consenting documentation. Accordingly, I am critical that Dr B did not ensure that ‘paraplegia’ or ‘paralysis’ were listed as risks on the consent form. This criticism is mitigated by the fact that, overall, the consenting process appears to have been reasonable. I note that there is clear documentation of a thorough consenting discussion being completed during the clinic before the operation. This included discussion of the significant risk of nerve damage resulting in paraplegia. It was noted that Mr A appeared to have understood the risks of the procedure. Further evidence to support the occurrence of in-depth discussions regarding risks of the operation, including paralysis, was recorded in the typed operation note. Although I acknowledge Mr A’s recollection that he was not aware of such risk, given the passage of time I have relied upon and prefer what has been documented contemporaneously or closer in time to the procedure. I note also that Mr A has acknowledged that he was aware ‘there [was] a 5% chance that things may go wrong.’
Dr Johnson was critical of Dr B for his decision not to explore the lipoma in the sacral region. Dr B told HDC that he was concerned about potential damage to neural tissue if he explored that area. He also stated that this decision was discussed with his colleagues at the pre-surgical MDTM meeting on 11 August 2016. I accept that Dr B and his colleagues decided against exploration of this area because of the perceived risk of potentially causing damage to neural tissue. However, I would expect that discussions on the direction of treatment would be recorded in detail to ensure that the rationale for such decisions is clearly documented and readily accessible.
Regarding Mr A’s concern that Dr B did not disclose the error that he made during surgery, I note that Dr B was unaware that he had operated at the wrong level until an MRI scan was completed in the months after the operation. Dr B told HDC that he informed Mr A of the error and apologised once he became aware of what had happened. Unfortunately, I have not received clinical records detailing any such discussion. In the absence of this information, I am critical that Dr B did not appropriately document what was discussed with Mr A regarding this error but otherwise am unable to make further findings on this matter.
Dr Johnson did not identify any departures regarding the care Dr B provided following the surgery (and immediate postoperative care) of 18 November 2016, and I accept his opinion.
Changes made since events
Dr B advised that he has made the following changes to his practice since these events:
He now performs pre-incision and post-incision X-rays for all spinal surgeries to ensure he is operating at the correct level.
Intraoperative neuro-monitoring has become more widely available since 2017, and Dr B uses it for all intradural spinal operations and some extradural spinal operations (excluding emergency cases). This is a further check that he is operating at the correct level.
All complex intradural spinal cases are discussed preoperatively in a neurosurgical MDTM.
Dr B works on difficult intraspinal cases with the assistance of a colleague. For paediatric spinal detethering cases, he works with a paediatric surgery consultant.
Dr B now requests postoperative MRIs for nearly all intradural spinal pathologies, regardless of whether the patient has deteriorated.
Recommendations and follow-up actions
I recommend that Dr B provide a formal written apology to Mr A for the deficiencies identified in this report. The apology is to be sent to HDC within three weeks of the date of this report, for forwarding to Mr A.
I recommend that Dr B and Health NZ Waikato reflect on the wording used on surgical consent forms for spinal procedures and, if required, provide further training to the neurosurgical team in relation to the completion of consent documentation. In particular, clinicians should ensure that the terms ‘paralysis’ and/or ‘paraplegia’ are stated as risks for any neurosurgical operation on the spine. Following any further training as required, Health NZ Waikato is to complete an audit of the last 10 neurosurgical consent forms for spinal procedures to ensure that risks are being appropriately recorded. A copy of the audit findings (and any corrective actions) is to be provided to HDC within three months of the date of this report.
I recommend that Dr B and Health NZ Waikato reflect on the detail of decisions and the rationale recorded in neurosurgical MDTMs. If required, further guidance should be given to clinicians regarding the expected detail of documentation. Following any further training that may be identified, Health NZ Waikato is to complete an audit of the last 10 neurosurgical MDTMs to ensure that discussions are being appropriately recorded. A copy of the audit findings (and any corrective actions taken) are to be provided to HDC within three months of the date of this report.
I trust that Dr B will reflect on his documentation to ensure that any conversations with patients regarding perioperative complications are appropriately recorded in that patient’s clinical records.
Noting the remedial changes that Dr B has made to his clinical practice since these events, which I consider address the key issues identified with the care he provided Mr A, and given the time that has elapsed since the provision of care, I do not propose to make any further recommendations relating to the care he provided.
A copy of this report with details identifying the parties removed, except the clinical advisor on this case and Health NZ Waikato, will be sent to the Medical Council of New Zealand, and it will be advised of Dr B’s name.
A copy of this report with details identifying the parties removed, except Health NZ Waikato and the clinical advisor on this case, will be sent to the Royal Australasian College of Surgeons and placed on the Health and Disability Commissioner website (www.hdc.org.nz) for educational purposes.
Morag McDowell
Health and Disability Commissioner