Wrong site surgeries are considered potentially preventable errors that are associated with unnecessary cost and morbidity. Operations at the wrong spinal level may result in the need for additional surgery that could have been avoided.

While the true incidence of wrong-level surgery is difficult to determine due to under-reporting, retrospective case series have reported rates from 0.032% to 15%.¹,²,³,⁴ Eie et al. reported a rate of 2.12% in 943 patients over a 5-year period at a single institution.⁵ In an anonymous web-based survey of 1045 members of the American Association of Neurological Surgeons/Congress of Neurological Surgeons (AANS/CNS) Spine and Peripheral Nerve section, 47% of the 569 respondents reported having performed wrong site surgery at least once during their career, of which 18% resulted in consequent litigation.⁶

In a separate survey of 3505 AANS members, 50% of the 415 respondents reported at least one wrong-level surgery in their careers, and 15% reported wrong-level exposure with correct-level surgery after appropriate intraoperative radiographic confirmation.⁷ The authors extrapolated a wrong-level surgery prevalence of 0.03%. Of these, 71% occurred in the lumbar spine.

Additionally, 17% of wrong-level spine surgeries resulted in a lawsuit. In a review of the American Board of Orthopaedic Surgery database of orthopedic surgeons undergoing certification, a single lumbar laminectomy was the most common wrong-level procedure reported.⁸

The causes for wrong-level surgery are multifactorial. Reported causes include difficulty to visualize known reference points, failure to obtain proper confirmatory intraoperative imaging,⁸,⁹ poor communication, unconventional spinal anatomy,⁸,¹⁰,¹¹,¹²,¹³ large body habitus, poor counting methods, and surgeon fatigue or inexperience.¹⁴

In a survey of 2338 surgeons through the North American Spine Society (NASS) with 173 respondents, the most common preoperative error was due to unconventional anatomy.¹ In these cases, while the surgeon may be using the correct counting techniques, the inability to recognize abnormal or distorted anatomy can result
in wrong-level surgery. In the cervical spine, abnormal anatomy from prior fusion or Klippel-Feil syndrome can complicate localization due to the lack of disc spaces for counting. The thoracic spine can be challenging for localization, particularly at the midthoracic level due to the uniform appearance of adjacent levels.

Additionally, scoliosis, variable number of vertebra with ribs, distance from landmarks, and scapular/humoral shadow on imaging can make localization difficult.

In the lumbar spine, counting up from L5/S1 can result in erroneous localization if there are transitional anatomy at the lumbosacral junction. In patients with four or six lumbar vertebra, the nomenclature for identifying each level may vary based on counting cephalad or caudal.

Nonuniform descriptors such as “sacral transitional vertebra,” “partially fused vertebra,” or “lumbarized sacrum” can lead to confusion when describing these anatomical variants.

Similarly, counting down utilizing ribs as an anatomical landmark can be confounded by abnormal number of ribs.¹⁵ In a separate survey, abnormal anatomy has accounted for 16% of wrong-level spine surgeries.¹⁶

Low-quality radiographs from osteoporosis, previous surgery, or scoliosis can make localization more difficult.¹⁷ In particular, large body habitus has also been cited as a possible cause for wrong-level surgery as excessive fatty tissue can diminish imaging quality.³,¹⁵ In the cervical spine, large shoulders can obscure intraoperative fluoroscopy for identifying the lower cervical spine.

Up to 30% of wrong-level spine surgery has been attributed to failure to relocalize after initial exposure.¹⁸ The marking identifying the correct spinal level can be moved or distorted during the initial exposure.¹⁵ While preoperative imaging can identify key landmarks, confirmatory intraoperative imaging is still critical in minimizing localization errors.¹⁴,¹⁹,²⁰

Several professional societies have made protocols aimed at eliminating wrong site, wrong patient, and wrong procedure events. The Universal Protocol established by The Joint Commission involves patient and procedure verification preoperatively, appropriate surgical site marking, and a surgical team time-out prior making incision. The “Sign, Mark & X-ray” (SMaX) guidelines, which were recommended by the NASS, involves a checklist comprising preoperative verification with appropriate consents and imaging, a time-out, site marking, and vertebral level identification techniques.

However, the efficacy of these societal guidelines in preventing wrong-level spine surgery is unclear.¹²,¹⁹,²¹,²² Some authors suggest that while the Universal Protocol maybe effective in decreasing incidence of wrong site surgery in nonspine procedures, it is not effective in the setting of wrong-level spine surgery.⁸ In a systematic literature review, Longo et al. concluded that there is insufficient evidence that site-verification protocols are effective in decreasing the incidence of wrong-level spine surgery.²³

Since the inception of societal guidelines such as the Universal Protocol, wrong-level spine surgeries have still been reported.¹⁸,²⁴ Barriers to the effective implementation of surgical checklists include provider resistance and the perception of decreased team efficacy and comfort.²⁵ Given the importance of changing provider behavior and attitude towards safety, Lau et al. designed a perioperative neurosurgical safety video to streamline and standardize critical safety checks and
communication practices that should occur with every neurosurgical procedure.²⁴ The 10-minute video aimed at helping create a culture of safety was designed for a multidisciplinary neurosurgical provider team.