Search Results

You are looking at 1 - 8 of 8 items for

  • Author or Editor: Robert S. Pashman x
Clear All Modify Search
Restricted access

J. Patrick Johnson, Robert S. Pashman, Carl Lauryssen, Neel Anand, John J. Regan and Robert S. Bray

✓ Spinal deformity has classically and historically been studied by those in the discipline of orthopedic surgery. This may be attributable to the orthopedic interventionalists' experience with osseous fixation for long-bone and other skeletal fractures. Neurosurgeons have maintained a long-standing interest in complex cervical spinal disorders, and their interest in the larger field of complex spinal deformity has been expanding.

An understanding of spinal deformity disorders, biomechanics, bone biology, and metallurgy is necessary before clinical, teaching, and research activities can be undertaken within neurosurgery.

The authors describe basic and advanced concepts of spinal deformity management with cases to illustrate teaching points.

Free access

Terrence T. Kim, Doniel Drazin, Faris Shweikeh, Robert Pashman and J. Patrick Johnson

Object

Intraoperative CT image–guided navigation (IGN) has been increasingly incorporated into minimally invasive spine surgery (MIS). The vast improvement in image resolution and virtual real-time images with CT-IGN has proven superiority over traditional fluoroscopic techniques. The authors describe their perioperative MIS technique using the O-arm with navigation, and they report their postoperative experience, accuracy results, and technical aspects.

Methods

A retrospective review of 48 consecutive adult patients undergoing minimally invasive percutaneous posterior spinal fusion with intraoperative CT-IGN between July 2010 and August 2013 at Cedars-Sinai Medical Center was performed. Two surgeons assessed 290 screws in a blinded fashion on intraoperative O-arm images and postoperative CT scans for bony pedicle wall breach. Grade 1 breach was defined to be < 2 mm, Grade 2 breach to be between 2 and 4 mm, and a Grade 3 breach to be > 4 mm. Additionally, anterior vertebral body breach was recorded.

Results

Of 290 pedicle screws placed, 280 (96.6%) were in an acceptable position without cortical wall or anterior breach. Of the 10 breaches (3.4%) 5 were lateral (50%), 4 were medial, and 1 was anterior; 90% of breaches were Grade 1–2 and all medial breaches were Grade 1. The one Grade 3 breach was lateral. No vascular or neurological complications were observed intraoperatively, and no significant postoperative complications were noted. The mean clinical follow-up period was 18 months (range 3–39 months). The overall clinical outcomes, measured using the visual analog scale (back pain scores), were improved significantly postoperatively at 3 months compared with preoperatively (visual analog score 6.35 vs 3.57; p < 0.0001). No revision surgery was performed for screw misplacement or neurological deterioration.

Conclusions

New CT-IGN with the mobile O-arm scanner has increased the accuracy of pedicle screw/instrumentation placement using MIS techniques. The authors' high (96.6%) accuracy rate in MIS compares favorably with historical published accuracy rates for fluoroscopy-based techniques. Additional advantages of CT-IGN over fluoroscopic imaging methods are lower occupational radiation exposure for the surgical team, reduced need for postoperative imaging, and decreased rates of revision surgery. For now, the authors simply conclude that use of intraoperative CT-IGN is safe and accurate.

Full access

Doniel Drazin, Ali Shirzadi, Sunil Jeswani, Harry Ching, Jack Rosner, Alexandre Rasouli, Terrence Kim, Robert Pashman and J. Patrick Johnson

Object

Athletes present with back pain as a common symptom. Various sports involve repetitive hyperextension of the spine along with axial loading and appear to predispose athletes to the spinal pathology spondylolysis. Many athletes with acute back pain require nonsurgical treatment methods; however, persistent recurrent back pain may indicate degenerative disc disease or spondylolysis. Young athletes have a greater incidence of spondylolysis. Surgical solutions are many, and yet there are relatively few data in the literature on both the techniques and outcomes of spondylolytic repair in athletes. In this study, the authors undertook a review of the surgical techniques and outcomes in the treatment of symptomatic spondylolysis in athletes.

Methods

A systematic review of the MEDLINE and PubMed databases was performed using the following key words to identify articles published between 1950 and 2011: “spondylolysis,” “pars fracture,” “repair,” “athlete,” and/or “sport.” Papers on both athletes and nonathletes were included in the review. Articles were read for data on methodology (retrospective vs prospective), type of treatment, number of patients, mean patient age, and mean follow-up.

Results

Eighteen articles were included in the review. Eighty-four athletes and 279 nonathletes with a mean age of 20 and 21 years, respectively, composed the population under review. Most of the fractures occurred at L-5 in both patient groups, specifically 96% and 92%, respectively. The average follow-up period was 26 months for athletes and 86 months for nonathletes. According to the modified Henderson criteria, 84% (71 of 84) of the athletes returned to their sports activities. The time intervals until their return ranged from 5 to 12 months.

Conclusions

For a young athlete with a symptomatic pars defect, any of the described techniques of repair would probably produce acceptable results. An appropriate preoperative workup is important. The ideal candidate is younger than 20 years with minimal or no listhesis and no degenerative changes of the disc. Limited participation in sports can be expected from 5 to 12 months postoperatively.

Restricted access

Srinath Samudrala, Shoshanna Vaynman, Ty Thiayananthan, Samer Ghostine, Darren L. Bergey, Neel Anand, Robert S. Pashman and J. Patrick Johnson

Object

Sagittal plane deformities can be subdivided into kyphotic and lordotic forms and further characterized according to their global or regional (focal) presentation. Regional deformities of a significant magnitude constitute a gibbous deformity. Pedicle subtraction osteotomy (PSO) and interlaminar Smith-Petersen osteotomies have been used to correct sagittal plane deformities in the cervical, thoracic, and lumbar spine. By resecting a portion of the vertebral body and closing in the gap of this vertebra, the spine is placed in local lordosis and kyphosis is corrected. These osteotomies have generally been carried out in the lumbar or less frequently in the thoracic area. While PSO has been performed in the mid and lower thoracic spine, there have been no case series of patients undergoing PSO at the CTJ. Specifically, a PSO approach that addresses the challenges of the CTJ is needed. Here, the authors review their case series of PSOs performed in the CTJ. Their goal in the treatment of these patients was to correct the regional CTJ kyphosis, restore forward gaze, and reduce the pain associated with the deformity.

Methods

Eight patients (5 males and 3 females, mean age 63 years) underwent PSO for the correction of CTJ kyphosis. Pedicle subtraction osteotomy was performed at C-7 or the upper thoracic vertebrae and was facilitated by a computer-guided intraoperative monitoring system. Surgical indications included postlaminectomy kyphosis, spinal cord tumor resection, posttraumatic kyphosis, and degenerative cervical spondylosis.

Results

The mean follow-up was 15.3 months (range 12–20 months), and the mean preoperative CTJ kyphosis was 38.67° (range 25°–60°). Clinically satisfactory correction of the regional deformity was accomplished in all patients, achieving a mean correction of 35.63° (range 15°–66°) at the CTJ, with restoration of forward gaze and significant reduction in pain.

Conclusions

A CTJ deformity is a distinctive form of kyphosis that presents as a variable local deformity and requires complex spinal reconstructive techniques to restore sagittal balance and forward gaze. Pedicle subtraction osteotomy allows for significant correction through one spinal segment, and it can be used safely to correct the regional sagittal alignment of the cervical spine and head in relation to the pelvis. Pedicle subtraction osteotomy can be used alone or in combination with other techniques as some patients may require multistage procedures with anterior and posterior spinal reconstruction to obtain stable sagittal correction. All deformities in these patients were kyphotic in nature with only mild elements of scoliosis or coronal plane deformity. This is unlike lumbar and thoracic curves where the kyphosis is frequently associated with scoliosis.

Free access

Joseph C. Hsieh, Doniel Drazin, Alexander O. Firempong, Robert Pashman, J. Patrick Johnson and Terrence T. Kim

Object

Revision spine surgery, which is challenging due to disrupted anatomy, poor fluoroscopic imaging, and altered tactile feedback, may benefit from CT image-guided surgery (CT-IGS). This study evaluates accuracy of CT-IGS–navigated screws in primary versus revision spine surgery.

Methods

Pedicle and pelvic screws placed with the O-arm in 28 primary (313 screws) and 33 revision (429 screws) cases in which institutional postoperative CT scans were available were retrospectively reviewed for placement accuracy. Screw accuracy was categorized as 1) good (< 1-mm pedicle breach in any direction or “in-out-in” thoracic screws through the lateral thoracic pedicle wall and in the costovertebral joint); 2) fair (1- to 3-mm breach); or 3) poor (> 3-mm breach).

Results

Use of CT-IGS resulted in high rates of good or fair screws for both primary (98.7%) and revision (98.6%) cases. Rates of good or fair screws were comparable for the following regions: C7–T3 at 100% (good or fair) in primary versus 100% (good or fair) in revision; T4–9 at 96.8% versus 100%; T10–L2 at 98.2% versus 99.3%; L3–5 at 100% versus 99.2%; and pelvis at 98.7% versus 98.6%, respectively. On the other hand, revision sacral screws had statistically significantly lower rates of good placement compared with primary (100% primary vs 80.6% revision, p = 0.027). Of these revision sacral screws, 11.1% had poor placement, with bicortical screws extending > 3 mm beyond the anterior cortex. Revision pelvic screws demonstrated the highest rate of fair placement (28%), with the mode of medial breach in all cases directed into the sacral-iliac joint.

Conclusions

In the cervical, thoracic, and lumbar spine, CT-IGS demonstrated comparable accuracy rates for both primary and revision spine surgery. Use of 3D imaging of the bony pedicle anatomy appears to be sufficient for the spine surgeon to overcome the difficulties associated with instrumentation in revision cases. Although the bony structures of sacral pedicles and pelvis are relatively larger, the complexity of local anatomy was not overcome with CT-IGS, and an increased trend toward inaccurate screw placement was demonstrated.

Free access

Sunil Jeswani, Doniel Drazin, Joseph C. Hsieh, Faris Shweikeh, Eric Friedman, Robert Pashman, J. Patrick Johnson and Terrence T. Kim

Object

Traditionally, instrumentation of thoracic pedicles has been more difficult because of their relatively smaller size. Thoracic pedicles are at risk for violation during surgical instrumentation, as is commonly seen in patients with scoliosis and in women. The laterally based “in-out-in” approach, which technically results in a lateral breach, is sometimes used in small pedicles to decrease the comparative risk of a medial breach with neurological involvement. In this study the authors evaluated the role of CT image–guided surgery in navigating screws in small thoracic pedicles.

Methods

Thoracic (T1–12) pedicle screw placements using the O-arm imaging system (Medtronic Inc.) were evaluated for accuracy with preoperative and postoperative CT. “Small” pedicles were defined as those ≤ 3 mm in the narrowest diameter orthogonal to the long axis of the pedicle on a trajectory entering the vertebral body on preinstrumentation CT. A subset of “very small” pedicles (≤ 2 mm in the narrowest diameter, 13 pedicles) was also analyzed. Screw accuracy was categorized as good (< 1 mm of pedicle breach in any direction or in-out-in screws), fair (1–3 mm of breach), or poor (> 3 mm of breach).

Results

Twenty-one consecutive patients (age range 32–71 years) had large (45 screws) and small (52 screws) thoracic pedicles. The median pedicle diameter was 2.5 mm (range 0.9–3 mm) for small and 3.9 mm (3.1–6.7 mm) for large pedicles. Computed tomography–guided surgical navigation led to accurate screw placement in both small (good 100%, fair 0%, poor 0%) and large (good 96.6%, fair 0%, poor 3.4%) pedicles. Good screw placement in very small or small pedicles occurred with an in-out-in trajectory more often than in large pedicles (large 6.8% vs small 36.5%, p < 0.0005; vs very small 69.2%, p < 0.0001). There were no medial breaches even though 75 of the 97 screws were placed in postmenopausal women, traditionally at higher risk for osteoporosis.

Conclusions

Computed tomography–guided surgical navigation allows for safe, effective, and accurate instrumentation of small (≤ 3 mm) to very small (≤ 2 mm) thoracic pedicles.