The medicolegal implications of complications following spinal surgery

Spinal surgery may be contemplated for several conditions, including congenital abnormalities, degenerative conditions, traumatic injury and tumours. Often, these procedures are complex. Therefore, the frequency of complications is relatively high, occurring in up to 20% of patients. While some of these unwanted effects are mild, others can be devastating for the patient and even lead to death. Spinal surgery complications can be divided into those that arise during surgery itself, and issues that become apparent after the procedure, including those with delayed onset.

Of the intraoperative complications, neurological injuries are probably the most feared. They arise when either the spinal cord or one or more nerve roots are damaged and take the form of either a worsening of current neurological status or a new neurological deficit. Several measures can be taken to avoid neurological injury during surgery, including careful planning, and positioning of the patient before and during the procedure, and intraoperative electrophysiologic monitoring which allows issues to be identified quickly. The use of high-dose steroids can also help to reduce traumatic oedema and the potential for spinal compression. If compression does occur, it should be relieved immediately, even to the extent of reversing deformity correction if necessary.  

Although cerebral spinal fluid (CSF) leaks can occur intraoperatively, they can also cause issues postoperatively, as they can impair wound healing and promote infection. In patients with cancer, leaks can also lead to intradural tumour seeding. In the event of a leak, repair should be undertaken immediately, as ongoing leaks can lead to cerebrospinal fluid hypotension and intracranial subdural haematomas. Temporary lumbar drainage may be needed to decrease the level of hydrostatic pressure on the repaired area. CSF leaks rarely cause longer term effects, but can slow down recovery, and wound healing, and can lead to the need for further surgery.  

Injuries to adjacent structures can occur during spinal surgery. In the posterior approach to the facet joints, and in the anterior approach to the organs and blood vessels. Major vascular damage can be life-threatening, and immediate attempts should be made to control the bleeding. Vascular surgeons are often present, and may be required to repair the damage. Oesophageal and bowel injuries may also require specialist interventions. Damage to the gastrointestinal tract can significantly increase the risk of infection and consideration should be given to appropriate management postoperatively. The risk of misplaced screws causing damage to adjacent structures can be reduced by the use of image intensifier, or navigated operating techniques, which have a higher level of screw placement accuracy.

Issues with wound healing are the most frequently encountered of the postoperative complications. Management of wound breakdown can be challenging and lead to considerable morbidity. Additionally, surgery involving removal of a tumour or other resected tissue can create a large dead space within the spine that must also be addressed. These cases often benefit from intervention by a plastic surgeon to ensure adequate closure of the dead space and coverage of the surgical site. Plastic surgery may also be required in cases of repeated wound infection or breakdown. Wounds in the sacral area are particularly prone to breakdown, as there is limited soft tissue available for adequate wound closure. Signs of infection or dehiscence should be treated promptly with antibiotics. As the causal organisms can differ from those commonly seen in orthopaedic surgery, infections may present in an unusual way, and often there is insidious infection without widespread systemic involvement. Therefore, clinicians should maintain a high index of suspicion for signs of infection.  

Failure of spinal reconstruction can also be a major issue. This may be due to poor surgical technique, poor bone quality which impedes healing, and instrumentation failure. The latter can beparticularly difficult to manage, as scarring and broken bone or instrumentation can present the surgeon with even fewer options for repair than for the original procedure. Further surgery is warranted if the failure increases the risk of further injury to the patient or causes mobility-limiting pain.  

As well as the risk of complications themselves,several additional issues must be considered during surgery for spinal tumours. This type of surgery requires the suspension of adjuvant therapies such as chemotherapy to allow the healing of the surgical site. Surgical complications, especially if they involve wound healing, may prolong the time that a patient goes without these life-prolonging therapies and could ultimately shorten the patient’s life. This is compounded by the fact that patients with cancer are more likely to develop a surgical site infection, due to immunosuppressive therapies, previous radiation of the site, and comorbidities such as anaemia and poor nutritional status. In patients with a relatively long-life expectancy, the long-term durability of the procedure must also be considered. Therefore, emphasis on maintaining or restoring biomechanical function of the spine with bony fusion is important.

Several other factors increase the risk of complications following spinal surgery. These include blood loss during surgery, duration of surgery, procedures involving more than one site, and comorbid conditions, including atrial fibrillation, metastatic tumours and obesity. Patient age may also be a factor. Therefore, assessment of the patient’s current disease status, comorbidities and neurological status must be fully investigated before surgery takes place, as these will determine the expected surgical benefits and anticipated complications. The patient should be given reasonable expectations regardinguseful neurological function and pain reduction after surgery, which will reduce the likelihood of subsequent litigation for negligence.