C-Arm-Free Circumferential Minimally Invasive Surgery for Adult Spinal Deformity: Technical Note

Lateral access minimally invasive spine surgery in adult spinal deformity

Background

Oblique lumbar interbody fusion (OLIF) and percutaneous posterior approach for screw fixation (PPS) is the latest minimal invasive treatment for spinal deformity in adult patients (ASD). This study aims to design and highlight key points for ASD correction.

Materials and methods

We retrospectively analyzed 54 patients who had undergone OLIF with PPS for ASD from October 2019 to January 2022 (average 71.5 ± 6.2 years-old, male 4, female 50) with a mean follow-up period of 29.2 months. Clinical outcomes are expressed by values including the Oswestry disability index (ODI) and visual analogue scale (VAS) for back pain. The imagistic assessment was also performed preoperatively and at 12, and 24 months postoperatively. For OLIF51, CT- MRI fusion images were obtained before surgery.

Results

Postoperative ODI and VAS were 30.5 ± 18.9% and 31.2 ± 6.9 mm, respectively. The average operating time and blood loss during the surgical exposure was 490.9 ± 85.4 min and 1195.2 ± 653.8 ml. Preoperative SVA, PI-LL, and PT were 96.5 ± 55.9 mm, 39.3 ± 22.1°, 34.5 ± 11.0°, respectively. Postoperatively, SVA and PT became normal (24.1 ± 39.0 mm, 17.1 ± 10.3°) and PI-LL was ideal (2.4 ± 12.6°). Postoperative ODI and VAS were 30.5 ± 18.9% and 31.2 ± 6.9 mm. For OLIF51, the results revealed gain in L5-S1 lordosis and intervertebral disc height 9.4° and 4.2 mm respectively. The complications consisted of PJK in 21 cases (38.9%), rod breakage in 5 cases (9.3%), deep or superficial wound infection in 2 cases (3.7%).

Conclusion

Clinical and imagistic results of OLIF and PPS for ASD were excellent. The radiographic measurements revealed that OLIF51 created good L5-S1 lordosis and significant L5-S1 disc height. CT-MRI fusion images were very useful for evaluating vascular anatomy for OLIF51.

Comparison of C-Arm-Free Oblique Lumbar Interbody Fusion L5-S1 (OLIF51) with Transforaminal Lumbar Interbody Fusion L5-S1 (TLIF51) for Adult Spinal Deformity

Background and Objectives: Adult spinal deformity (ASD) surgery, L5-S1 lordosis is very important factor. The main objective of the research is to retrospectively compare symptomatic presentation and radiological presentation in the sequelae of oblique lumbar inter-body spinal fusion at L5-S1 (OLIF51) and transforaminal lumbar interbody fusion (TLIF) for ASD. Materials and Methods: We retrospectively evaluated 54 patients who underwent corrective spinal fusion for ASD between October 2019 and January 2021. Thirteen patients underwent OLIF51 (average 74.6 years old, group O) and 41 patients underwent TLIF51 (average 70.5 years old, group T). Mean follow-up period was 23.9 months for group O and 28.9 months for group T, ranging from 12 to 43 months. Clinical and radiographic outcomes are assessed using values including visual analogue scale (VAS) for back pain and Oswestry disability index (ODI). Radiographic evaluation was also collected preoperatively and at 6, 12, and 24 months postoperatively. Results: Surgical time in group O was less than that in group T (356 min vs. 492 min, p = 0.003). However, intraoperative blood loss of both groups were not significantly different (1016 mL vs. 1252 mL, p = 0.274). Changes in VAS and ODI were similar in both groups. L5-S1 angle gain and L5-S1 height gain in group O were significantly better than those of group T (9.4° vs. 1.6°, p = 0.0001, 4.2 mm vs. 0.8 mm, p = 0.0002). Conclusions: Clinical outcomes were not significantly different in both groups, but surgical time in OLIF51 was significantly less than that in TLIF51. The radiographic outcomes showed that OLIF51 created more L5-S1 lordosis and L5-S1 disc height compared with TLIF 51.

Chronological Evaluation of Gait Ability and Posture Balance after Adult Spinal Deformity Surgery

Adult spinal deformity (ASD) is highly prevalent in persons older than 65 years, affecting more than 30% of the total population. There are many important reports that describe excellent postoperative results for ASD surgery. However, there is no report that describes a chronological evaluation of gait ability and spinal balance after ASD surgery. The present prospective study aimed to determine the recovery time of gait and spinal balance ability after adult spinal deformity (ASD) surgery. Patients with ASD (n = 25: mean age, 73.0 years) who underwent corrective surgery and preoperative and postoperative gait and spinal balance ability evaluation. Spinal radiographs and gait analysis data (static balance; single-leg standing, dynamic balance; time-up and go test, gait ability; 10 m walk velocity) were acquired preoperatively, 1 month, 6 months, and 12 months after surgery. The radiographic parameters of the spine and pelvis (lumbar lordosis; LL, pelvic tilt; PT, sagittal vertical axis; SVA, pelvic incidence; PI) were measured. The mean postoperative SVA, LL, PT, and PI-LL became 30.0 mm, 50.1 degrees, 14.1 degrees, and 0.35 degrees, respectively. Preoperatively, all spinal balance and gait ability were worse than the normal threshold (one-leg standing; 14.2 s vs. 15.0 s, time-up and go test; 13.9 s vs. 13.5 s, 10-m walk speed; 0.91 m/s vs. 1.00 m/s). At 12 months after surgery, all spinal balance and gait ability became normal or improved (single-leg standing; 14.7 s, time-up and go test; 11.0 s, 10-m walk speed; 1.09 m/s). The ODI at one-year follow-up improved from 46.8 ± 12.6% to 27.8 ± 18.1%. In conclusion, gait and spinal balance analysis revealed that ASD patients could not recover gait and spinal balance ability one month after surgery. At 12 months after surgery, gait ability and dynamic spinal balance became better than preoperative levels. However, the static spinal balance was at the same level as that of preoperative status.

Comparison of Simultaneous Single-Position Oblique Lumbar Interbody Fusion and Percutaneous Pedicle Screw Fixation with Posterior Lumbar Interbody Fusion Using O-arm Navigated Technique for Lumbar Degenerative Diseases

Minimally invasive posterior or transforaminal lumbar interbody fusion (MI-PLIF/TLIF) are widely accepted procedures for lumbar instability due to degenerative or traumatic diseases. Oblique lateral interbody fusion (OLIF) is currently receiving considerable attention because of the reductions in damage to the back muscles and neural tissue. The aim of this study was to compare clinical and radiographic outcomes of simultaneous single-position OLIF and percutaneous pedicle screw (PPS) fixation with MI-PLIF/TLIF. This retrospective comparative study included 98 patients, comprising 63 patients with single-position OLIF (Group SO) and 35 patients with MI-PLIF/TLIF (Group P/T). Cases with more than 1 year of follow-up were included in this study. Mean follow-up was 32.9 ± 7.0 months for Group SO and 33.7 ± 7.5 months for Group P/T. Clinical and radiological evaluations were performed. Comparing Group SO to Group P/T, surgical time and blood loss were 118 versus 172 min (p < 0.01) and 139 versus 374 mL (p < 0.01), respectively. Cage height, change in disk height, and postoperative foraminal height were significantly higher in Group SO than in Group P/T. The fusion rate was 96.8% in Group SO, similar to the 94.2% in Group P/T (p = 0.985). The complication rate was 6.3% in Group SO and 14.1% in Group P/T (p = 0.191). Simultaneous single position O-arm-navigated OLIF reduces the surgical time, blood loss, and time to ambulation after surgery. Good indirect decompression can be achieved with this method.

Comparative Study of Bilateral Dual Sacral-Alar-Iliac Screws versus Bilateral Single Sacral-Alar-Iliac Screw for Adult Spine Deformities

OBJECTIVE

To evaluate the feasibility of O-arm navigation of bilateral dual sacral-alar-iliac (SAI) screws compared with conventional bilateral single SAI and S1 pedicle screws for pelvic anchors in cases of adult spinal deformity.

METHODS

This retrospective, comparative study included 39 patients who underwent corrective fusion using SAI screws from T10 to the pelvis. Patients were divided into 2 groups according to the number of SAI screws placed during adult spinal deformity surgery: single SAI screw (group S, 17 cases) and dual SAI screws (group D, 22 cases). The incidence of rod breakage, proximal junctional kyphosis, screw loosening, reoperation, and global alignment in each group was estimated. Postoperative patient-reported outcomes were measured using the Oswestry Disability Index, Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, and visual analog scale.

RESULTS

The incidence of SAI screw loosening was significantly lower in group D than in group S (23% vs. 65%, P = 0.011). The rod breakage incidence was 0% and 12% in groups D and S, respectively (P = 0.17). There were no significant differences in the postoperative global alignment and clinical outcomes between the 2 groups.

CONCLUSIONS

Dual SAI screws were associated with a significantly reduced incidence of screw loosening compared with single SAI screws. The bilateral dual SAI screws technique for pelvic anchors is feasible for the treatment of patients with adult spinal deformity.

Assessment of 3D Lumbosacral Vascular Anatomy for OLIF51 by Non-Enhanced MRI and CT Medical Image Fusion Technique

Study design: Prospective study. Objective: Medical image fusion can provide information from multiple modalities in a single image. The present study aimed to determine whether three-dimensional (3D) lumbosacral vascular anatomy could be adequately portrayed using a non-enhanced CT–MRI medical image fusion technique. Summary of Background Data: Lateral lumbar interbody fusion has gained popularity for the surgical treatment of adult spinal deformity (ASD). Oblique lumbar interbody fusion at L5–S1 (OLIF51) is receiving considerable attention as a method of creating good L5–S1 lordosis. Access in OLIF51 requires evaluation of the vascular anatomy in the lumbosacral region. Conventional imaging modalities need a contrast medium to describe the vascular anatomy. Methods: Participants comprised 15 patients with ASD or degenerative lumbar disease who underwent corrective surgery at our hospital between January 2020 and June 2021. A 3D vascular image with bony structures was obtained by fusing results from MRI and CT. We processed the merged image and measured the distance between left and right common iliac arteries and veins at two levels: the lower end of the L5 vertebral body (Window A) and the upper end of the S1 vertebral body (Window B). Results: The mean sizes of Window A and Window B were 29.7 ± 10.7 mm and 36.9 ± 10.3 mm, respectively. The mean distance from the bifurcation to the lower end of the L5 vertebra was 23.7 ± 10.9 mm. Coronal deviation of the bifurcation was, from center to left, 12.6 ± 12.3 mm, and the distance from the center of the L5 vertebral body to the bifurcation was 0.79 ± 7.3 mm. Only one case showed a median sacral vein (6.7%). Clinically, we performed OLIF51 in 12 of the 15 cases (80%). Conclusion: Evaluating 3D lumbosacral vascular anatomy using a non-enhanced MRI and CT medical image fusion technique is very useful for OLIF51, particularly for patients in whom the use of contrast medium is contraindicated.

Minimally Invasive L5 Corpectomy with Navigated Expandable Vertebral Cage: A Technical Note

Background: Conventional L5 corpectomy requires a large incision and an extended period of intraoperative fluoroscopy. We describe herein a new L5 corpectomy technique. Methods: A 79-year-old woman was referred to our hospital for leg pain and lower back pain due to an L5 vertebral fracture. Her daily life had been affected by severe lower back pain and sciatica for more than 2 months. We initially performed simple decompression surgery, but this proved effective for only 10 months. Results: For revision surgery, the patient underwent minimally invasive L5 corpectomy with a navigated expandable cage without fluoroscopy. The second surgery took 215 min, and estimated blood loss was 750 mL. The revision surgery proved successful, and the patient could then walk using a cane. In terms of clinical outcomes, the Oswestry Disability Index improved from 66% to 24%, and the visual analog scale score for lower back pain improved from 84 to 31 mm at the 1-year follow-up. Conclusions: Minimally invasive L5 corpectomy with a navigated expandable vertebral cage is effective for reducing cage misplacement and surgical invasiveness. With this new technique, surgeons and operating room staff can avoid the risk of adverse events due to intraoperative radiation exposure.

Percutaneous C-Arm Free O-Arm Navigated Biopsy for Spinal Pathologies: A Technical Note

BACKGROUND

Percutaneous biopsy under computed tomography (CT) guidance is a standard technique to obtain a definitive diagnosis when spinal tumors, metastases or infections are suspected. However, specimens obtained using a needle are sometimes inadequate for correct diagnosis. This report describes a unique biopsy technique which is C-arm free O-arm navigated using microforceps. This has not been previously described as a biopsy procedure.

CASE DESCRIPTION

A 74-year-old man with T1 vertebra pathology was referred to our hospital with muscle weakness of the right hand, clumsiness and cervicothoracic pain. CT-guided biopsy was performed, but histopathological diagnosis could not be obtained due to insufficient tissue. The patient then underwent biopsy under O-arm navigation, so we could obtain sufficient tissue and small cell carcinoma was diagnosed on histopathological examination. A patient later received chemotherapy and radiation.

CONCLUSIONS

C-arm free O-arm navigated biopsy is an effective technique for obtaining sufficient material from spine pathologies. Tissue from an exact pathological site can be obtained with 3-D images. This new O-arm navigation biopsy may provide an alternative to repeat CT-guided or open biopsy.

Navigated Lateral Osteotomy for Adult Spinal Deformity: A Technical Note

BACKGROUND

Minimally invasive surgery is receiving considerable attention as a technique for reducing the complications of adult spinal deformity (ASD) surgery. For this technique, a new lateral osteotomy plays an important role to release fused vertebrae. We describe herein a novel navigated lateral osteotomy technique not requiring C-arm fluoroscopy to correct adult spinal deformities.

CASE DESCRIPTION

A 68-year-old woman with symptomatic ASD and a 4-year history of severe low back pain affecting daily life was referred to our hospital. Surgery was performed without C-arm fluoroscopy. A navigated osteotome was used to release the fused L1/2 mass. The patient was successfully treated with surgery, and low back pain was well controlled. In terms of clinical outcomes, Oswestry Disability Index improved from 64%-19% and Visual Analog Scale score for low back pain improved from 74 mm-19 mm on final follow-up at 2 years.

CONCLUSIONS

This novel navigated lateral osteotomy for ASD is a useful technique that enables minimally invasive surgery for fixed deformity. With this new technique, surgeons and operating room staff can avoid adverse effects of intraoperative radiation.

C-Arm-Free Anterior Correction for Adolescent Idiopathic Scoliosis (Lenke Type 5C): Analysis of Early Outcomes and Complications

BACKGROUND

Computer-assisted spinal surgery as a technique for reducing radiation exposure to the operating staff and the complications of spinal deformity are receiving considerable attention. However, no technical reports have described the technique for navigating anterior correction of adolescent idiopathic scoliosis without C-arm fluoroscopy. The purpose of this study was to evaluate the efficacy and safety of this new C-arm-free anterior correction for scoliosis.

METHODS

This study investigated 38 consecutive patients with Lenke type 5C curves who underwent selective lumbar or thoracolumbar fusion, comprising 26 patients with conventional anterior correction surgery, and 12 patients with C-arm-free navigation surgery. The 2 groups were evaluated immediately postoperatively and at the 2-year follow-up.

RESULTS

No vascular injuries, screw malpositioning, or major complications were associated with the surgical procedure in either group. Correction rates of the lumbar curve were satisfactory with no significant difference between groups (mean, 82.6% ± 5.7% vs. 80.7% ± 10.2%, respectively). However, mean time for fluoroscopy in group C was 133 ± 9.5 seconds (P < 0.0001). No significant differences in intraoperative blood loss (642 ± 123 mL vs. 731 ± 222 mL, respectively) or surgical time (251 ± 13 min vs. 301 ± 38 min, respectively) were seen between groups. Mean final follow-up Scoliosis Research Society Outcomes Questionnaire (SRS-22) was also excellent for both group C (4.2 ± 0.19) and group N (4.3 ± 0.20).

CONCLUSIONS

C-arm-free anterior correction offers safe, effective surgery for adolescent idiopathic scoliosis. The advantage of this new technique is no radiation exposure for medical staff at centers performing large numbers of spinal procedures.

Effect of an Adjustable Hinged Carbon Fiber Operating Table on the Coronal Alignment of the Lumbar Spine During Oblique Lateral Interbody Fusion

OBJECTIVE

We sought to measure the coronal alignment of the lumbar spine of patients in the right lateral decubitus position on a hinged Jackson operating table with the following 3 table positions: neutral and right and left 20-degree flexion.

METHODS

We analyzed the data of 23 patients who underwent OLIF. Spinal alignment was quantified using the coronal Cobb angle from L1 to S1, measured on anterior-posterior radiographs obtained preoperatively, after induction of anesthesia, with patients in the right lateral decubitus position, for the following 3 positions of the Jackson hinged operating table: neutral, right 20-degree flexion, and left 20-degree flexion. The Cobb angle at each position, the change in the Cobb angle, and the effective range of motion (%) were obtained from neutral to right and left 20-degree flexion. Alignment was compared between the 3 positions, and the range of motion was compared between men and women.

RESULTS

The Cobb angle was different in all 3 positions of the table (P < 0.0001): -7.0 ± 8.7°, neutral; 2.8 ± 7.6°, right 20-degree flexion; and -14.7 ± 7.8°, left 20-degree flexion. The change in Cobb angle and the effective range of motion were greater in women (10.9 ± 2.8° and 55%) than in men (6.7 ± 5.8° and 34%) from the neutral to right 20-degree flexion position (P = 0.0298).

CONCLUSIONS

The coronal alignment of the lumbar spine of patients in the right lateral decubitus position on a flat operating table (neutral position) was convex. The right 20-degree flexion position of the hinged operating table yielded less coronal plane lumbar spine deformity, with greater deformity in women.