scholarly journals A case series of eight scoliosis patients undergone pedicle screw placement with freehand technique: study for safety and accuracy

2020 ◽  
Vol 29 (2) ◽  
pp. 222-7
Author(s):  
Komang Agung Irianto ◽  
Marquee Kenny Tumbelaka

BACKGROUND Pedicle screws and rods are routinely inserted in the vertebrae thoracic to lumbar in scoliosis reconstruction surgery to gain deformity correction and fusion. Intraoperative imaging is often needed to ensure accuracy, but surgical time will be longer and there will be more radiation exposure. Meanwhile, freehand technique is accepted as safe. This study was aimed to evaluate the accuracy of screw insertion in the freehand technique used in adolescent scoliosis surgery. METHODS This case series evaluated a total of 127 pedicle screws inserted using the freehand technique in 8 out of 28 adolescent scoliosis patients from 2011 to 2016 whom agreed for computed tomography (CT) scan follow-up from 2011 to 2016 in Dr. Seotomo Hospital, Surabaya. The accuracy and safety of the freehand technique were evaluated postoperatively in each patient using a CT scan. A successful screw was considered accurate if it was within the vertebral body and inside the safety zone within the limit of 2–4 mm to the medial or lateral side of the vertebral body. RESULTS Of the 127 screws inserted, 106 (83.5%) were accurately placed, and 110 (86.6%) were within the safe zone. According to the level of the spine, in the upper and middle thoracic spine, the inserted screws were accurate in 69.4% and 74.9% within the safety zone, whereas in the lower thoracic and lumbar spine, 94.0% and 95.0% within the safety zone. CONCLUSIONS The freehand technique in scoliosis reconstructive surgery performed by experienced surgeons is accurate and safe. 

Author(s):  
Cesare Faldini ◽  
Francesca Barile ◽  
Fabrizio Perna ◽  
Stefano Pasini ◽  
Michele Fiore ◽  
...  

Abstract Purpose The aim of this article is to present an original surgical technique for the treatment of rigid Adult Idiopathic Scoliosis (AdIS) and the results at minimum 2 years follow-up in a cohort of 40 patients. Methods We retrospectively reviewed 40 patients affected by rigid AdIS, older than 40 years and operated with a posterior one stage surgical technique summarized with the acronym Hi-PoAD, (high-density pedicle screws, Ponte osteotomies, asymmetric rods contouring, direct vertebral rotation). The demographic and surgical data were collected, and the improvement of clinical scores and radiologic parameters was obtained after surgery, at 1 and 2 years and at final follow-up, to assess deformity correction, coronal and sagittal balance and clinical outcome. Results The average follow-up was 2.9 years (range 2–3.5). Average coronal Cobb angle decreased from 65.0° ± 8.4 to 18.9° ± 3.9 (p < 0.01). Rotation sagittal angle decreased from 26.2° ± 4.4° to 12.4° ± 2.8° (p < 0.01). Mean thoracic kyphosis improved from 23.1° ± 3.6° to 36.0° ± 3.9°. SRS-22 improved form 2.9 ± 0.4 to 3.7 ± 0.6 (p < 0.01). Four early post-operative deep wound infections were observed, all healed after debridement and implant retention. No mechanical complication, junctional kyphosis, deformity progression or non-union were recorded at the last follow-up. Conclusions Hi-PoAD technique proved to be safe and effective in the treatment of rigid Adult Idiopathic Scoliosis. The reason for the success is related to the combined strategies adopted, that dissipates corrective forces over several levels, reducing mechanical stress at the screw–bone interface and optimizing corrective potential.


1995 ◽  
Vol 82 (1) ◽  
pp. 11-16 ◽  
Author(s):  
Edward C. Benzel ◽  
Nevan G. Baldwin

✓ An ideal spinal construct should immobilize only the unstable spinal segments, and thus only the segments fused. Pedicle fixation techniques have provided operative stabilization with the instrumentation of a minimal number of spinal segments; however, some failures have been observed with pedicle instrumentation. These failures are primarily related to excessive preload forces and limitations caused by the size and orientation of the pedicles. To circumvent these problems, a new technique, the crossed-screw fixation method, was developed and is described in this report. This technique facilitates short-segment spinal fixation and uses a lateral extracavitary approach, which provides generous exposure for spinal decompression and interbody fusion. The technique employs two large transverse vertebral body screws (6.5 to 8.5 mm in diameter) to bear axial loads, and two unilateral pedicle screws (placed on the side of the exposure) to restrict flexion and extension deformation around the transverse screws and to provide three-dimensional deformity correction. The horizontal vertebral body and the pedicle screws are connected to rods and then to each other via rigid crosslinking. The transverse vertebral body screws are unloaded during insertion by placing the construct in a compression mode after the interbody bone graft is placed, thus optimizing the advantage gained by the significant “toe-in” configuration provided and further decreasing the chance for instrumentation failure. The initial results of this technique are reported in a series of 10 consecutively treated patients, in whom correction of the deformity was facilitated. Follow-up examination (average 10.1 months after surgery) demonstrated negligible angulation. Chronic pain was minimal. The crossed-screw fixation technique is biomechanically sound and offers a rapid and safe form of short-segment three-dimensional deformity correction and solid fixation when utilized in conjunction with the lateral extracavitary approach to the unstable thoracic and lumbar spine. This approach also facilitates the secure placement of an interbody bone graft.


2020 ◽  
pp. 219256822095697
Author(s):  
Benjamin D. Crawford ◽  
Corbyn M. Nchako ◽  
Kelsey A. Rebehn ◽  
Heidi Israel ◽  
Howard M. Place

Study Design: Retrospective cohort. Objective: The objective of this study was to assess the effectiveness of the O-arm as an intraoperative imaging tool by comparing accuracy of pedicle screw placement to freehand technique. Methods: The study comprised a total of 1161 screws placed within the cervical (n = 187) thoracic (n = 657), or lumbar (n = 317) spinal level. A pedicle breach was determined by any measurable displacement of the screw outside of the pedicle cortex in any plane on postoperative images. Each pedicle screw was subsequently classified by its placement relative to the targeted pedicle. Statistical analysis was then performed to determine the frequency and type of pedicle screw mispositioning that occurred using the O-arm versus freehand technique. Results: A total of 155 cases (O-arm 84, freehand 71) involved the placement of 454 pedicle screws in the O-arm group and 707 pedicle screws in the freehand group. A pedicle breach occurred in 89 (12.6%) screws in the freehand group and 55 (12.1%) in the O-arm group ( P = .811). Spinal level operated upon did not influence pedicle screw accuracy between groups ( P > .05). Three screws required revision surgery between the 2 groups (O-arm 1, freehand 2, P > .05). The most frequent breach type was a lateral pedicle breach (O-arm 22/454, 4.8%; freehand 54/707, 7.6%), without a significant difference between groups ( P > .05). Conclusions: The use of the O-arm coupled with navigation does not assure improved transpedicular screw placement accuracy when compared with the freehand technique.


2019 ◽  
Vol 30 (6) ◽  
pp. 807-813
Author(s):  
Vibhu K. Viswanathan ◽  
Amy J. Minnema ◽  
Stephanus Viljoen ◽  
H. Francis Farhadi

Sublaminar implants that encircle cortical bone are well-established adjuncts to pedicle screw-rod constructs in pediatric deformity surgery. Sublaminar bands (SLBs) in particular carry the advantage of relatively greater bone contact surface area as compared to wires and pullout loads that are independent of bone mineral density, in contrast to pedicle screws. Whereas the relevant technical considerations have been reported for pediatric deformity correction, an understanding of the relative procedural specifics of these techniques is missing for adult spinal deformity (ASD), despite several case series that have used distinct posterior tethering techniques for proximal junctional kyphosis prevention. In this paper, the authors summarize the relevant literature and describe a novel technique wherein bilateral tensioned SLBs are introduced at the nonfused proximal junctional level of long-segment ASD constructs.


2011 ◽  
Vol 31 (4) ◽  
pp. E11 ◽  
Author(s):  
Melvin D. Helgeson ◽  
Ronald A. Lehman ◽  
Anton E. Dmitriev ◽  
Daniel G. Kang ◽  
Rick C. Sasso ◽  
...  

Object Intraoperative imaging often does not provide adequate visualization to ensure safe placement of screws. Therefore, the authors investigated the accuracy of a freehand technique for placement of pars, pedicle, and intralaminar screws in C-2. Methods Sixteen cadaveric specimens were instrumented freehand by 2 experienced cervical spine surgeons with either a pars or pedicle screw, and bilateral intralaminar screws. The technique was based on anatomical starting points and published screw trajectories. A pedicle finder was used to establish the trajectory, followed by tapping, palpation, and screw placement. After placement of all screws (16 pars screws, 16 pedicle screws, and 32 intralaminar screws), the C-2 segments were disarticulated, radiographed in anteroposterior, lateral, and axial planes, and meticulously inspected by another spine surgeon to determine the nature and presence of any defects. Results A total of 64 screws were evaluated in this study. Pars screws exhibited 2 critical defects (1 in the foramen transversarium and 1 in the C2–3 facet) and an insignificant dorsal cortex breech, for an overall accuracy rate of 81.3%. Pedicle screws demonstrated only 1 insignificant violation (inferior facet/medial cortex intrusion of 1 mm) with an accuracy rate of 93.8%, and intralaminar screws demonstrated 3 insignificant violations (2 in the ventral canal, 1 in the caudad lamina breech) for an accuracy rate of 90.6%. Pars screws had significantly more critical violations than intralaminar screws (p = 0.041). Conclusions Instrumentation of the C-2 vertebrae using the freehand technique for insertion of pedicle and intralaminar screws showed a high success rate with no critical violations. Pars screw insertion was not as reliable, with 2 critical violations from a total of 16 placements. The freehand technique appears to be a safe and reliable method for insertion of C-2 pedicle and intralaminar screws.


2018 ◽  
Vol 1 (2) ◽  
pp. 2
Author(s):  
Chiung Chyi Shen

Use of pedicle screws is widespread in spinal surgery for degenerative, traumatic, and oncological diseases. The conventional technique is based on the recognition of anatomic landmarks, preparation and palpation of cortices of the pedicle under control of an intraoperative C-arm (iC-arm) fluoroscopy. With these conventional methods, the median pedicle screw accuracy ranges from 86.7% to 93.8%, even if perforation rates range from 21.1% to 39.8%.The development of novel intraoperative navigational techniques, commonly referred to as image-guided surgery (IGS), provide simultaneous and multiplanar views of spinal anatomy. IGS technology can increase the accuracy of spinal instrumentation procedures and improve patient safety. These systems, such as fluoroscopy-based image guidance ("virtual fluoroscopy") and computed tomography (CT)-based computer-guidance systems, have sensibly minimized risk of pedicle screw misplacement, with overall perforation rates ranging from between 14.3% and 9.3%, respectively."Virtual fluoroscopy" allows simultaneous two-dimensional (2D) guidance in multiple planes, but does not provide any axial images; quality of images is directly dependent on the resolution of the acquired fluoroscopic projections. Furthermore, computer-assisted surgical navigation systems decrease the reliance on intraoperative imaging, thus reducing the use of intraprocedure ionizing radiation. The major limitation of this technique is related to the variation of the position of the patient from the preoperative CT scan, usually obtained before surgery in a supine position, and the operative position (prone). The next technological evolution is the use of an intraoperative CT (iCT) scan, which would allow us to solve the position-dependent changes, granting a higher accuracy in the navigation system. 


2021 ◽  
pp. 107110072110345
Author(s):  
Chien-Shun Wang ◽  
Yun-Hsuan Tzeng ◽  
Tzu-Cheng Yang ◽  
Chun-Cheng Lin ◽  
Ming-Chau Chang ◽  
...  

Background: Adult acquired flatfoot deformity (AAFD) and hallux valgus (HV) are common foot and ankle deformities. Few studies have reported the changes in radiographic parameters of HV after reconstructive surgery for AAFD. This study aimed to evaluate the changes in radiographic parameters of HV and analyze the risk factors for increased HV after correction of AAFD. Methods: Adult patients with flexible AAFD who underwent similar bony procedures including medializing calcaneal osteotomy and Cotton osteotomy were included. Radiographic parameters were measured on weightbearing radiographs preoperatively, postoperatively, and at the final follow-up. Patients were divided into hallux valgus angle (HVA) increased and HVA nonincreased groups; logistic regression analysis was performed to identify risk factors affecting increased HV. Results: Forty-six feet of 43 patients were included. After AAFD reconstructive surgery, the tibial sesamoid position improved by 1 grade, but the HVA increased 4 degrees in average. Further, 21 of 46 feet (46%) showed an HVA increase ≥5 degrees immediately after AAFD correction surgery. Preoperative talonavicular coverage angle <21.6 degrees was a risk factor associated with HV increase immediately after the surgery. Conclusion: In this case series, using plain radiographs to measure standard parameters of foot alignment, we found the association between AAFD correction and HV deformity measures somewhat paradoxical. Correction of overpronation of the hindfoot and midfoot appears to improve the first metatarsal rotational deformity but may also increase HVA. A lower preoperative talonavicular coverage angle was associated with an increase of the HVA after surgery. Level of Evidence: Level IV, case series study.


Author(s):  
Gabriele Colo’ ◽  
Mattia Alessio Mazzola ◽  
Giulio Pilone ◽  
Giacomo Dagnino ◽  
Lamberto Felli

Abstract The aim of this study is to evaluate the results of patients underwent lateral open wedge calcaneus osteotomy with bony allograft augmentation combined with tibialis posterior and tibialis anterior tenodesis. Twenty-two patients underwent adult-acquired flatfoot deformity were retrospectively evaluated with a minimum 2-year follow-up. Radiographic preoperative and final comparison of tibio-calcaneal angle, talo–first metatarsal and calcaneal pitch angles have been performed. The Visual Analog Scale, American Orthopedic Foot and Ankle Score, the Foot and Ankle Disability Index and the Foot and Ankle Ability Measure were used for subjective and functional assessment. The instrumental range of motion has been also assessed at latest follow-up evaluation and compared with preoperative value. There was a significant improvement of final mean values of clinical scores (p < 0.001). Nineteen out of 22 (86.4%) patients resulted very satisfied or satisfied for the clinical result. There was a significant improvement of the radiographic parameters (p < 0.001). There were no differences between preoperative and final values of range of motion. One failure occurred 7 years after surgery. Adult-acquired flatfoot deformity correction demonstrated good mid-term results and low recurrence and complications rate. Level of evidence Level 4, retrospective case series.


Sign in / Sign up

Export Citation Format

Share Document