Table 2.

Results of pedicle subtraction osteotomy for spinal pseudarthrosis complicating ankylosing spondylitis reported in the literature and in the current study

Author (year)	No. cases operated	Surgical method	Clinical/radiological outcome	Complications
Chang [4] (2006)	30	Posterior opening-wedge osteotomy	A mean correction of 38° for local kyphosis	Postoperative pneumonia in 1 patient Superficial infection in 1 patient
Van Royen [23] (2006)	2	Transpedicular wedge resection osteotomy	The correction of kyphosis was 24° and 31°, respectively	Incomplete neurological deficit in 1 patient
Kim [16] (2007)	12	Smith-Petersen osteotomy or pedicle subtraction osteotomy with anterior interbody fusion in one-stage or two-stage	The mean correction was 20.9° with Smith-Petersen osteotomy and 26.3° with pedicle subtraction osteotomy	Dural tears in 3 cases Leg pain with paresthesia in 2 patients Early deep wound infection in 1 patient
Current study	7	Pedicle subtraction osteotomy through pseudarthrosis combined with anterior interbody fusion	The kyphosis was corrected from 75º to 30º, with a mean correction of 45º. Solid bony fusion achieved at the final follow-up	No perioperative complications