Staged osteotomy in lateral position for the treatment of severe kyphotic deformity secondary to ankylosing spondylitis: a retrospective study

Multiple three-column osteotomies successfully correcting cervicothoracic kyphosis in the setting of ankylosing spondylitis: illustrative case

BACKGROUND

Ankylosing spondylitis (AS) is an autoimmune spondylarthritis often associated with rigid kyphoscoliosis. The authors describe a surgical approach that employs multilevel three-column osteotomies for the restoration of normal global alignment.

OBSERVATIONS

A 48-year-old male with a past medical history of AS presented to the clinic with a stooped-over posture: his chin-brow vertical angle (CBVA) was 58.0°; T1 slope (T1S), 97.8°; thoracic kyphosis (TK; T1-12), 94.2°; proximal TK (T1-5), 50.8°; distal TK (T5-12), 43.5°; and sagittal vertical axis (SVA), 22.6 cm. A two-stage procedure was planned. During stage 1, instrumentation was placed from C5 to T10, followed by a T3 vertebral column resection. During stage 2, bilateral pedicle screws were placed from T11 to the pelvis. An L3 pedicle subtraction osteotomy (PSO) was completed and was followed by a T7 PSO. Postoperatively, the patient had significant postural improvement: CBVA was 29.3°; T1S, 57.8°; TK, 77.3°; proximal TK, 33.5°; distal TK, 43.8°; and SVA, 15 cm. At 6 years postoperatively, the patient continued to do well and was without evidence of construct breakdown.

LESSONS

The authors propose that multilevel three-column osteotomies, if optimally located, successfully correct spinal malalignment associated with AS.

[Effectiveness of combined anteversion angle technique in total hip arthroplasty for treatment of ankylosing spondylitis affecting hip joint]

Objective

To explore the effectiveness of the combined anteversion angle technique in total hip arthroplasty (THA) for treating ankylosing spondylitis (AS) affecting the hip joint.

Methods

A retrospective analysis was conducted on the clinical data of 73 patients with AS affecting the hip joint who underwent THA between August 2018 and August 2021. According to whether the combined anteversion angle technique was used in THA, the patients were divided into study group (37 cases, combined anteversion angle technique was used in THA) and control group (36 cases, traditional THA). There was no significant difference in baseline data such as gender, age, body mass index, disease duration, preoperative Harris score, range of motion (ROM), acetabular anteversion angle, acetabular abduction angle, femoral anteversion angle, and combined anteversion angle between the two groups ( P>0.05). The operation time, hospital stay, and complications of the two groups were recorded and compared. The Harris score and hip ROM were compared between the two groups before operation, at 1, 3, 6, 12 months after operation, and at last follow-up. The acetabular component anteversion angle, femoral component anteversion angle, acetabular component abduction angle, and component combined anteversion angle were measured postoperatively.

Results

The operation time in the study group was significantly shorter than that in the control group ( P<0.05), and there was no significant difference in hospital stay between the two groups ( P>0.05). There was no intraoperative complication such as acetabular and proximal femoral fractures, neurovascular injuries in both groups, and the incisions healed by first intention. All patients were followed up 2-3 years, with an average of 2.4 years; there was no significant difference in the follow-up time between the two groups ( P>0.05). During the follow-up period, there was no complication such as hip dislocation, wound infection, delayed wound healing, deep venous thrombosis, and hip dislocation in both groups. The hip Harris score and ROM of the two groups gradually increased with time after operation, and the differences were significant when compared with those before operation ( P<0.05); the above two indicators of the study group were significantly better than those of the control group at each time point after operation ( P<0.05). Extensive bone ingrowth on the surface of the components could be observed in the anteroposterior X-ray films of the hip joint of the two groups at 12 months after operation, and the acetabular components was stable without femoral stem subsidence, osteolysis around the components, and heterotopic ossification. At last follow-up, the acetabular component anteversion angle, femoral component anteversion angle, and component combined anteversion angle in the study group were significantly superior to those in the control group ( P<0.05), except that there was no significant difference in the acetabular component abduction angle between the two groups ( P>0.05).

Conclusion

For patients with AS affecting the hip joint, the use of the combined anteversion angle technique during THA effectively promotes the recovery of hip joint function and enhances the postoperative quality of life of patients when compared to traditional THA.

Long-term outcome evaluation in ankylosing spondylitis with high-angle thoracolumbar kyphotic deformity corrected by one-stage single-level pedicle subtraction osteotomy augmented with Ponte osteotomy: A case series

INTRODUCTION AND IMPORTANCE

A high-angle thoracolumbar kyphotic deformity (TLKD) may complicate surgical rectification of AS patients since one-stage two-level pedicle subtraction osteotomy (PSO), which provides high-angular correction, leads to excessive blood loss, neurological deficits and fixation failures. This case series presents the long-term results of one-stage single level PSO with Ponte osteotomy (PO) in the treatment of AS patients with high-angle TLKD.

CASE PRESENTATION

This case series presents two AS patients with high kyphotic angles (KAs) of 86.1o. We collected data retrospectively from our institution's database between 2019 and 2023. A sagittal axis imbalance was the only complaint initially, no neurological deficits or other problems. A PSO augmented by PO was performed with a decompression laminectomy. Intraoperative monitoring (IOM) during reduction was used to observe neurological deficits. Blood loss at the highest rate was 1000 cc. It corrected 57.8o of KA postoperatively without neurological deficits. We found consistent results over 36 months.

CLINICAL DISCUSSION

A thorough analytical approach may help diagnose AS. One-stage single-level PSO may correct high-angle TLKD in AS patients effectively. To achieve greater angular correction, PO, a less risky osteotomy, must be added. Decompression laminectomy is vital before osteotomy and IOM is crucial during reduction to prevent nerve injury. Even with two osteotomies, there was less blood loss than previously reported. These impressive long-term results call for further research.

CONCLUSION

Combined PSO and PO with IOM efficiently magnifies the angular correction without postoperative neurological deficits or excessive blood loss in AS patients with high-angle TLKD.