Recurrence of proximal junctional kyphosis after revision surgery for symptomatic proximal junctional kyphosis in patients with adult spinal deformity: incidence, risk factors, and outcomes.

PURPOSE: Although proximal junctional kyphosis (PJK) is common after long spinal fusion, the outcomes of revision surgery for symptomatic PJK are unclear. Our aim was to assess the outcomes of revision surgery for symptomatic PJK in patients with adult spinal deformity and elucidate the incidence and risk factors for recurrent PJK (rePJK). METHODS: We evaluated standing radiographs and health-related quality of life (HRQOL) in patients who underwent revision surgery for symptomatic PJK with at least 2-year follow-up. Patients were assigned to the non-rePJK or rePJK group according to PJK recurrence. RESULTS: Thirty-nine consecutive patients (mean age, 63 ± 11 years; 24 women) met the inclusion criteria. RePJK occurred in 12 patients (31%). There were significant differences in the following parameters between groups (non-rePJK vs. rePJK): initial proximal junctional sagittal Cobb angle (PJA) (26.6° vs. 35.6°), thoracic kyphosis (TK) (38.6° vs. 52.8°), and sagittal vertical axis (SVA) (9.3 vs. 15.9 cm), and pre- to postoperative SVA decrease (6.1 vs. 12.2 cm). Significant risk factors for rePJK were initial PJA > 40°, preoperative TK > 60°, preoperative SVA > 10.0 cm, correction of TK > 15°, and correction of SVA > 5.0 cm. HRQOL scores improved significantly; however, postoperative SRS-22r activity scores were significantly worse in the rePJK group vs the non-rePJK group. CONCLUSION: The incidence of rePJK was 31%. Risk factors for rePJK were large initial PJA, high preoperative TK and SVA, and greater correction of TK and SVA. HRQOL did not differ significantly between patients with vs without rePJK, except immediate postoperative SRS-22r activity scores. LEVEL OF EVIDENCE: III.

Clinical results and functional outcomes after three-column osteotomy at L5 or the sacrum in adult spinal deformity.

PURPOSE: Three-column osteotomies at L5 or the sacrum (LS3COs) are technically challenging, yet they may be needed to treat lumbosacral kyphotic deformities. We investigated radiographic and clinical outcomes after LS3CO. METHODS: We analyzed 25 consecutive patients (mean age 56 years) who underwent LS3CO with minimum 2-year follow-up. Standing radiographs and health-related quality-of-life scores were evaluated. A new radiographic parameter ["lumbosacral angle" (LSA)] was introduced to evaluate sagittal alignment distal to the S1 segment. RESULTS: From preoperatively to the final follow-up, significant improvements occurred in lumbar lordosis (from - 34° to - 49°), LSA (from 0.5° to 22°), and sagittal vertical axis (SVA) (from 18 to 7.3 cm) (all, p < .01). Mean Scoliosis Research Society (SRS)-22r scores in activity, pain, self-image, and satisfaction (p < .05), and Oswestry Disability Index scores (p < .01) also improved significantly. Patients with SVA ≥ 5 cm at the final follow-up experienced less improvement in SRS-22r satisfaction scores than those with SVA < 5 cm. Patients with LSA < 20° at the final follow-up had significantly lower SRS-22r activity scores than those with LSA ≥ 20° (p = .014). Two patients had transient neurologic deficits, and 11 patients underwent revision for proximal junctional kyphosis (5), pseudarthrosis (3), junctional stenosis (2), or neurologic deficit (1). CONCLUSIONS: LS3CO produced radiographic and clinical improvements. However, patients who remained sagittally imbalanced had less improvement in SRS-22r satisfaction score than those whose sagittal imbalance was corrected, and patients who maintained kyphotic deformity in the lumbosacral spine had lower SRS-22r activity scores than those whose lumbosacral kyphosis was corrected. These slides can be retrieved under Electronic Supplementary Material.

Caudally directed upper-instrumented vertebra pedicle screws associated with minimized risk of proximal junctional failure in patients with long posterior spinal fusion for adult spinal deformity.

BACKGROUND CONTEXT: It is unknown whether upper instrumented vertebra (UIV) pedicle screw trajectory and UIV screw-rod angle are associated with development of proximal junctional kyphosis (PJK) and/or proximal junctional failure (PJF). PURPOSE: To determine whether (1) the cranial-caudal trajectory of UIV pedicle screws and (2) UIV screw-vertebra angle are associated with PJK and/or PJF after long posterior spinal fusion in patients with adult spinal deformity (ASD). STUDY DESIGN/SETTING: Retrospective review. PATIENT SAMPLE: We included 96 patients with ASD who underwent fusion from T9-T12 to the pelvis (>5 vertebrae fused) between 2008 and 2015. OUTCOME MEASURES: Pedicle screw trajectory was measured as the UIV pedicle screw-vertebra angle (UIV-PVA), which is the mean of the two angles between the UIV superior endplate and both UIV pedicle screws. (Positive values indicate screws angled cranially; negative values indicate screws angled caudally.) We measured UIV rod-vertebra angle (UIV-RVA) between the rod at the point of screw attachment and the UIV superior endplate. METHODS: During ≥2-year follow-up, 38 patients developed PJK, and 28 developed PJF. Mean (± standard deviation) UIV-PVA was -0.9° ± 6.0°. Mean UIV-RVA was 87° ± 5.2°. We examined the development of PJK and PJF using a UIV-PVA/UIV-RVA cutoff of 3° identified by a receiver operating characteristic curve, while controlling for osteoporosis, age, sex, and preoperative thoracic kyphosis. RESULTS: Patients with UIV-PVA ≥3° had significantly greater odds of developing PJK (odds ratio 2.7; 95% confidence interval: 1.0-7.1) and PJF (odds ratio 3.6; 95% confidence interval: 1.3-10) compared with patients with UIV-PVA <3°. UIV-RVA was not significantly associated with development of PJK or PJF. CONCLUSIONS: In long thoracic fusion to the pelvis for ASD, UIV-PVA ≥3° was associated with 2.7-fold greater odds of PJK and 3.6-fold greater odds of PJF compared with UIV-PVA <3°. UIV-RVA was not associated with PJK or PJF. LEVEL OF EVIDENCE: III.

Preoperative patient expectations and pain improvement after adult spinal deformity surgery.

OBJECTIVE: Patients' expectations for pain relief are associated with patient-reported outcomes after treatment, although this has not been examined in patients with adult spinal deformity (ASD). The aim of this study was to identify associations between patients' preoperative expectations for pain relief after ASD surgery and patient-reported pain at the 2-year follow-up. METHODS: The authors analyzed surgically treated ASD patients at a single institution who completed a survey question about expectations for back pain relief. Five ordinal answer choices to "I expect my back pain to improve" were used to categorize patients as having low or high expectations. Back pain was measured using the 10-point numeric rating scale (NRS) and Scoliosis Research Society-22r (SRS-22r) patient survey. Preoperative and postoperative pain were compared using analysis of covariance. RESULTS: Of 140 ASD patients eligible for 2-year follow-up, 105 patients (77 women) had pre- and postoperative data on patient expectations, 85 of whom had high expectations. The mean patient age was 59 ± 12 years, and 46 patients (44%) had undergone previous spine surgery. The high-expectations and low-expectations groups had similar baseline demographic and clinical characteristics (p > 0.05), except for lower SRS-22r mental health scores in those with low expectations. After controlling for baseline characteristics and mental health, the mean postoperative NRS score was significantly better (lower) in the high-expectations group (3.5 ± 3.5) than in the low-expectations group (5.4 ± 3.7) (p = 0.049). The mean postoperative SRS-22r pain score was significantly better (higher) in the high-expectations group (3.3 ± 1.1) than in the low-expectations group (2.6 ± 0.94) (p = 0.019). CONCLUSIONS: Despite similar baseline characteristics, patients with high preoperative expectations for back pain relief reported less pain 2 years after ASD surgery than patients with low preoperative expectations.