Retrospective study of postoperative outcomes of adult spinal deformity (ASD) surgery.
To clarify the differences in postoperative outcomes depending on the presence or absence of thoracic compensatory changes among patients with a T1 slope (TS) more than 40°.
Loss correction after ASD surgery is more likely to occur when preoperative TS is more than 40°. When preoperative TS is more than 40°, some cases involve compensatory changes in the thoracic spine and decreased thoracic kyphosis (TK); others involve increased TK without compensatory changes.
Seventy-nine patients with TS more than 40° who underwent ASD surgery were enrolled and separated into compensated and noncompensated groups (group C: TK <40°; group NC: TK ≥40°). Radiographic parameters obtained by whole-spine standing x-ray, the Oswestry Disability Index (ODI), and Scoliosis Research Society-22 (SRS-22) questionnaire were assessed.
There were 41 patients in group C and 38 patients in group NC. Preoperative significant differences in TS did not disappear after surgery (preoperative TS: group C and group NC = 46° and 55°, P < 0.001; just after surgery: group C and group NC = 27° and 40°, P < 0.001; 2 years later: group C and group NC = 34° and 47°, P < 0.001). There were no significant differences in ODI and all domains of the SRS-22 before surgery. However, 2 years after the surgery, ODI (38%), pain (3.5), self-image (3.0), and total (3.2) values of the SRS-22 for group NC were significantly worse than those (28%, 4.0, 3.4, and 3.5, respectively) for group C (P < 0.05).
Changes in the thoracic spine (TS and TK >40°) result in poor postoperative outcomes. Extending the upper instrumented vertebra (UIV) to the upper thoracic spine must be considered. Even when TS is more than 40°, TK less than 40°, and upper instrumented vertebra set to the lower thoracic level result in good postoperative outcomes.
Level of Evidence: 3
Changes in the thoracic spine (T1 slope [TS] and thoracic kyphosis [TK] >40°) result in poor postoperative outcomes. Even when TS is more than 40°, TK less than 40° and upper instrumented vertebra set to the lower thoracic level result in good postoperative outcomes.
∗Department of Orthopedic Surgery and Division of Geriatric Musculoskeletal Health, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
†Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Japan
‡Department of Orthopedic Surgery, Hamamatsu Medical Center, Hamamatsu, Japan.
Address correspondence and reprint requests to Shin Oe, MD, Department of Orthopedic Surgery and Division of Geriatric Musculoskeletal Health, Hamamatsu University School of Medicine, 1-20-1 Handayama Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan; E-mail: firstname.lastname@example.org
Received 27 March, 2018
Revised 22 August, 2018
Accepted 31 August, 2018
The manuscript submitted does not contain information about medical device(s)/drug(s).
Medtronic SofamorDanek Inc., Japan Medical Dyanamic Marketing Inc., and Meitoku Institution Jyuzen Memorial Hospital funds were received in support of this work.
Relevant financial activities outside the submitted work: board membership, grants.