Forty-three per cent of cervical spine deformity patients experience early complications following surgery with 24.4% of patients experiencing major complications, according to an International Spine Study Group presentation at EUROSPINE 2015 (2–4 September, Copenhagen, Denmark).
Christopher Ames, University of California, San Francisco, USA, and colleagues in the International Spine Study Group examined the early recovery of 78 patients undergoing cervical deformity surgeries, which are often complex and associated with a high rate of complications.
“Very few reports have described these complications,” explained Ames, “and most are retrospective, small case series, with varying pathologies and criteria to define cervical deformity.” Ames and colleagues believe that accurately defining complications associated with cervical deformities is “very important for preoperative patient counselling and perhaps, in future, for deciding which surgeries to offer these patients based upon their substrate frailty and predictive modelling.”
To be included, a cervical deformity patient had to exhibit one of: cervical kyphosis (C2–C7 Cobb angle >10 degrees), C2–C7 sagittal vertical axis ≥4cm, chin-brow vertical angle ≥10 degrees or cervical scoliosis (coronal Cobb angle ≥10 degrees). The most common deformity among patients was degenerative kyphosis (42%), followed by iatrogenic kyphosis (20%) and cervical kyphoscoliosis (9%).
The team used standardised forms to collect patient demographics and details or surgical treatment and outcome measures. Data collection forms documented complications at operative, perioperative and follow-up time points. Recorded complications were classified as minor or major and as early (within 30 days or surgery) or delayed (after 30 days of surgery). Fifty per cent of the patients had undergone previous cervical spine surgery and 67% had at least one comorbidity. Mean age was 60.7 years and 59% were women.
Of the 78 patients, 14% underwent anterior-only surgery, while 49% underwent posterior-only surgery and 37% were treated with a combination of the two approaches. Ames pointed out that these were not, in general, minor deformities or segmental corrections—the mean number of levels fused was 9, the mean operative time was 377 minutes and mean blood loss was 816ml. Nineteen per cent of patients also underwent a major osteotomy.
The most common early complication was dysphagia, reported by 9 (11.5%) patients, 7 cases of which were minor and 2 of which were major. Dysphagia was the most common minor complication. The most common major complications were new C5 motor deficit and deep wound infection, both reported by 5 (6.4%) patients. In total, 52 early complications were reported (26 minor and 26 major), affecting 34 (43.6%) patients. There was one (1.3%) mortality in the study as a result of cardiac arrest.
Although the team did look at the association between complication rates and clinical facts, Ames reported that they “did not find much.” There was no association with age, smoking status, osteoporosis or with the severity of deformity. This was also the case with operative parameters such as blood loss, operative time and number of levels fused.
Where a difference was found was when comparing different surgical approaches, with the anterior-only method resulting in far lower early complication rates—27.3% of patients—when compared with posterior-only surgery (complications for 68.4% of patients) and a combined approach (complications for 79.3% of patients). This trend was also true for the development of dysphagia.
The Group intend to continue their study, with 100 patients now involved.