Osteotomies through a fusion mass in the lumbar spine

Multilevel non-contiguous thoracic pedicle subtraction osteotomy for fixed rounded hyperkyphotic deformity of the thoraco-lumbar junction with anterior bony fusion: technical note

BACKGROUND

Fixed severe hyperkyphotic deformities spread over more than five vertebral levels represent a therapeutic challenge, especially when the deformity apex is located at the thoraco-lumbar junction, thus requiring a huge amount of correction. The aim of this article is to describe an innovative all-posterior corrective technique based on multilevel non-contiguous thoracic pedicle subtraction ostoeotomy (PSO).

MATERIALS AND METHODS

A retrospective review of three patients with fixed severe thoracic hyperkyphosis (a deformity angle of over 70°) with a thoraco-lumbar apex (between T11 and L1) treated by simultaneous two-level thoracic PSO and thoraco-lumbar posterior fusion was performed. Radiographic and clinical records were evaluated pre-operatively, post-operatively and at last follow-up (after a minimum of 2 years). Each variable was presented as mean ± SD (standard deviation). Statistical analyses were performed using paired t-tests (P value < 0.05 was considered significant).

RESULTS

The mean local deformity angle decreased by 75% (from 81.3° ± 2.1° to 20.7° ± 1.4°, p < 0.001), the post-operative thoracic kyphosis decreased by 46% (from 61.4° ± 2.4° to 33.2° ± 0.9°, p < 0.001) and the sagittal vertical axis decreased by 73% (from 14.7 cm ± 0.8 cm to 3.9 cm ± 0.3 cm, p < 0.001). No differences were observed in the radiological results between post-operative values and those at the final follow-up. The average Oswestry Disability Index (ODI) score reduced from 65.7 ± 1.8 pre-operatively to 17.3 ± 1.7 at last follow-up (p < 0.001). No neurological, mechanical nor infective complication occurred.

CONCLUSIONS

The presented technique, although technically demanding, proved to be a safe and effective alternative for the management of fixed severe thoraco-lumbar junction hyperkyphotic deformities.

LEVEL OF EVIDENCE

IV TRIAL REGISTRATION Retrospectively registered.

Anterior Lumbar Interbody Fusion (ALIF) L5-S1 with overpowering of posterior lumbosacral instrumentation and fusion mass: a reliable solution in revision spine surgery

BACKGROUND AND PURPOSE

In cases of spine surgical revisions of patients affected by sagittal malalignment, the restoration of the ideal lumbar lordosis (LL) is mandatory. ALIF procedures represent a powerful and effective approach to improve the LL in case of hypolordosis. This study evaluates the feasibility of ALIF to overpower posterior lumbar instrumentation and fusion mass in revision spine surgery and secondarily to estimate complications, clinical and radiological outcomes.

METHODS

This is a single-center retrospective analysis of prospectively collected data on the use of ALIF overpowering in cases of lumbosacral instrumentation and/or fusion. Demographic, comorbidity, corrective strategy adopted, surgical data, clinical and radiological results, and intraoperative and postoperative complications were recorded.

RESULTS

Twelve patients (3 male; 9 female) underwent overpowering ALIF L5-S1 were included in the study with a mean FU of 34.0 ± 13.4 months. In 10 cases, a posterior titanium instrumentation and fusion mass were present; in 2 patients, only a fusion mass was present. Indicators of pain and disability improved in all patients (p < 0.01). Sagittal realignment with the restoration of ideal spinopelvic parameters was obtained in all cases. One peritoneal lesion requiring intraoperative suture without sequelae, two cases of postoperative radiculopathy, and one posterior wound infection requiring surgical debridement and antibiotic therapy were reported.

CONCLUSIONS

Anterior implant of lordotic and hyperlordotic cages with increasing segmental lordosis is possible in the presence of posterior instrumentation and/or solid fusion mass. The biomechanical strength of this corrective technique can overcome posterior instrumentation and bone fusion resistance, therefore allowing a single-staged surgery for sagittal realignment.

[Correction of kyphotic fixed lumbar segments and hypolordosis with the transforaminal lumbar interbody fusion technique]

OBJECTIVE

Correction of a segmental or global lumbar hypolordosis to improve a sagittal imbalance.

INDICATIONS

Lumbar segments fixed in kyphosis; degenerative or posttraumatic hypolordotic deformity of the lumbar spine with sagittal imbalance.

CONTRAINDICATIONS

Bechterew disease; extended adhesions in the retroperitoneum.

SURGICAL TECHNIQUE

Segmental correction of a kyphotic fixed segment using a unilateral transforaminal approach to release the annulus and anterior longitudinal ligament. With an additional posterior V‑shaped osteotomy, a segmental correction of more than 20° could be achieved to improve a global sagittal imbalance.

POSTOPERATIVE MANAGEMENT

Back-friendly mobilisation starting the first day after surgery with support of a physiotherapist. No sports for 3-4 months.

RESULTS

In all, 25 patients with 33 kyphotic fixed lumbar segments were treated using a complete anterior release of the annulus and anterior longitudinal ligament via a unilateral transforaminal approach. This enabled a lordosizing correction of the segment between 5° and 29° (mean 11.4°) without any neurological or vascular complications. A total of 10 patients treated with an additional posterior osteotomy were corrected 14-29° (mean 19°). There was a loss of reduction of the lordotic correction (mean 1°; range 0-3°) in the X‑ray control at a minimum follow-up of 6 months (range 6-33 months).