Posterior interbody arthrodesis with a fibular strut graft in spondylolisthesis

Comparative Analysis of Three Posterior-Only Surgical Techniques for Isthmic L5-S1 Spondylolisthesis

OBJECTIVE

To compare adults with isthmic L5-S1 spondylolisthesis who were treated with three different surgical techniques: PS-only, TS, and transforaminal lumbar interbody fusion/posterior lumbar interbody fusion (TLIF/PLIF).

METHODS

This is a retrospective analysis of adults with L5-S1 isthmic spondylolisthesis (grade ≥2) who underwent primary all-posterior operations with pedicle screws. Patients were excluded if they had <1 year follow-up, anterior approaches, and trans-sacral fibular grafts. Patient demographics and surgical, radiographic, and clinical data were compared between groups based on the method of anterior column support: none (PS-only), TS, and TLIF/PLIF.

RESULTS

Sixty patients met inclusion criteria (male patients 21, female patients 39, average age 47 ± 15 years, PS-only 16; TS 20; TLIF/PLIF 24). TS patients more commonly had high-grade slips and markedly greater slip percentage, lumbosacral kyphosis, and pelvic incidence. The three groups were similar for smoking status, visual analog scores/Oswestry Disability Index scores (VAS/ODI), surgical data, and average follow-up (40.1 ± 31.2 months). All groups had similarly notable improvements in Meyerding grade and lumbosacral angle. Slip reduction percentage was similar between groups. While there was a markedly higher overall complication rate for PS-only constructs, all groups had similarly notable improvements in ODI and VAS back scores.

CONCLUSIONS

All-posterior techniques for L5-S1 isthmic spondylolisthesis resulted in excellent improvement in preoperative symptoms and HRQoL scores and similar radiographic alignment. Trans-sacral screws were more commonly used for high-grade slips. The use of anterior column support resulted in fewer overall complications than posterior-only instrumentation.

An Alternative Operative Approach to Lumbar Spondylolisthesis

Lumbosacral spondylolisthesis is a frequently encountered pathology with high-grade spondylolisthesis being the least common. A circumferential construct is usually the preferred treatment as these can resist the shearing forces present at L5-S1. However, the severity of the slip, sacral inclination, and the slip angle may make a traditional anterior approach difficult to achieve. In this case series, we present three patients with axial back pain that were treated with an anterior L5-S1 transvertebral cage. This technique is intended for both grade II spondylolisthesis and high sacral slope. The L5-S1 transvertebral cage may be sufficient to prevent further listhesis, fuse the patient, and alleviate axial back pain.

Reduction versus In Situ Fusion for Adult High-Grade Spondylolisthesis: A Systematic Review and Meta-Analysis

BACKGROUND

Surgical management of high-grade spondylolisthesis is controversial. Both reduction and in situ fusion are available options, but it remains unclear which approach provides better outcomes. We conducted a systematic review and meta-analysis of studies reporting outcomes following reduction or in situ fusion for adult high-grade spondylolisthesis.

METHODS

PubMed, Embase, Web of Science, and Cochrane databases were last searched on June 24, 2019. We identified 1236 studies after excluding duplicates. After screening, 15 studies were included in the meta-analysis. Random-effects models were used to pool effect estimates.

RESULTS

A total of 188 patients were analyzed. Compared with reduction, in situ fusion had a higher mean estimated blood loss (584 mL vs. 451 mL) and a clinically higher incidence of neurologic (48% vs. 15%), pseudarthrosis (13% vs. 8%), and infectious (20% vs. 10%) complications; however, these differences were not statistically significant. Reduction was associated with a clinically higher incidence of overall complications (32% vs. 25%) and dural tears (22% vs. 7%). Reduction provided better pain relief (mean difference [MD] = 5.24 vs. 4.77) and greater change in pelvic tilt (MD = 5.33 vs. 2.60); however, these differences were not statistically significant. Patients who underwent reduction had significantly greater decline in Oswestry Disability Index scores (MD = 55.7 vs. 11.5; P_interaction < 0.01) and greater change in slip angle (MD = 25.0 vs. 11.4; P_interaction = 0.01).

CONCLUSIONS

In management of adult high-grade spondylolisthesis, both approaches appeared to be safe and effective. Reduction appeared to offer better disability relief and spinopelvic parameter correction than in situ fusion.

Tibiotalocalcaneal Arthrodesis With Intramedullary Fibular Strut Graft With Adjuvant Hardware Fixation

Tibiotalocalcaneal arthrodesis (TTCA) is a well-established operative procedure for different severe pathologic conditions of the ankle and hindfoot joints. We present our results with a modified technique of TTCA using an intramedullary fibular strut graft in a series of complex cases of patients treated for multiple etiologies shown to have improved union rates. The technique involves inserting the fibular strut graft intramedullary after joint preparation and the use of either a Taylor spatial frame or plate and screws for definitive fixation. We reviewed the records of 16 patients who had undergone TTCA with this technique at our hospital from September 2013 to April 2015. Sixteen patients (10 males [62.5%] and 6 females [37.5%]) were included in the present study. These patients had complex cases and multiple risk factors, including diabetes, smoking, poor bone stock, and a history of previous surgeries. The mean follow-up time was 9.1 (range 9 to 18) months. Thirteen patients (81.2%) subsequently achieved union. The mean visual analog scale scores at the final follow-up examination had improved from 6.9 to 1.2. We suggest that our technique of TTCA with intramedullary fibular strut graft with fixation is a reasonable option to salvage complex cases with risk factors for operative complications.

High-grade spondylolisthesis treated using a modified Bohlman technique: results among multiple surgeons

OBJECT

The ideal surgical management of high-grade spondylolisthesis remains unclear. Concerns regarding the original Bohlman transsacral interbody fusion technique with stand-alone autologous fibular strut include late graft fracture and incomplete reduction of lumbosacral kyphosis. The authors' goal was to evaluate the radiographic and surgical outcomes of patients treated for high-grade spondylolisthesis with either transsacral S-1 screws or standard pedicle screw fixation augmenting the Bohlman posterior transsacral interbody fusion technique.

METHODS

A retrospective review of patients who underwent fusion for high-grade spondylolisthesis in which a Bohlman oblique posterior interbody fusion augmented with either transsacral or standard pedicle screw fixation was performed by 4 spine surgeons was completed. Estimated blood loss, operating time, perioperative complications, and need for revision surgery were evaluated. Upright pre- and postsurgical lumbar spine radiographs were compared for slip percent and slip angle.

RESULTS

Sixteen patients (12 female and 4 male) with an average age of 29 years (range 9-66 years) were evaluated. The average clinical follow-up was 78 months (range 5-137 months) and the average radiographic follow-up was 48 months (range 5-108 months). Ten L4-S1 and 6 L5-S1 fusions were performed. Five fibular struts and 11 titanium mesh cages were used for interbody fusion. Six patients had isolated transsacral screws placed, with 2 (33%) of the 6 requiring revision surgery for nonunion. No nonunions were observed in patients undergoing spanning pedicle screw fixation augmenting the interbody graft. Six patients experienced perioperative complications including 3 iliac crest site infections, 1 L-5 radiculopathy without motor involvement, 1 deep vein thrombosis, and 1 epidural hematoma requiring irrigation and debridement. The average estimated blood loss and operating times were 763 ml and 360 minutes, respectively. Slip percent improved from an average of 62% to 37% (n = 16; p < 0.01) and slip angle improved from an average of 18° to 8° (n = 16; p < 0.01). No patient experienced L-5 or other motor deficit postoperatively.

CONCLUSIONS

The modified Bohlman technique for treatment of high-grade spondylolisthesis has reproducible outcomes among multiple surgeons and results in significant improvements in slip percent and slip angle. Fusion rates were high (14 of 16; 88%), especially with spanning instrumentation augmenting the oblique interbody fusion. Rates of L-5 motor deficit were low in comparison with techniques involving reduction of the anterolisthesis.

Posterior Transpedicular Fibular Grafts and Interferential Screws for the Surgical Treatment of L5-S1 Spondyloptosis: Case Report of Four Patients With 8.5 Years' Follow-Up

STUDY DESIGN

Retrospective case series.

OBJECTIVE

To present long-term results using partial reduction and instrumented fusion adding an L5-S1 transpedicular fibular plus interferential screw construct to treat spondyloptosis.

SUMMARY OF BACKGROUND DATA

Several techniques have been described to treat high-grade spondylolisthesis. Reported complications include neurologic injuries, pseudarthrosis, slip progression, and instrumentation failure. We present a posterior-only approach with partial reduction and instrumentation to treat spondyloptosis. Interbody fusion is provided by fibular struts inserted through the S1 pedicles capturing L5, avoiding neural manipulation. Graft stress is supported using interferential screws placed through these same pedicles.

METHODS

Retrospective revision of 4 cases with grade V spondylolisthesis. Information analyzed was preoperative, postoperative, and final follow-up clinical and radiographic data, with final Scoliosis Research Society Questionnaire-22 outcomes. Pelvic incidence, sacral slope, pelvic tilt, L5 incidence, lumbar lordosis, L5 slip angle, lumbosacral angle, and sagittal vertical axis were measured. Fusion and complications were recorded.

RESULTS

Mean age was 25.7 ± 5.7 years. All men with isthmic spondyloptosis (Meyerding V; type 5/6, Spinal Deformity Study Group classification). There were 3 primary surgeries and 1 revision. Median fused levels were 2 (range, 2-2.75); mean operative time was 6.1 ± 0.8 hours and median transfusion units were 2 (percentile 2-5). Mean follow-up was 102 months (range, 24-157 months). Postoperative pain using Visual Analog Score decreased from 7.1 ± 2.4 to 1.3 ± 1.3. Pelvic tilt improved 9.7°, whereas L5 incidence improved 15° and lumbosacral angle and L5 slip angle improved over 30°, which was maintained over time. Sagittal vertical axis improved by 1.6 cm; however, the improvement was lost by the final follow-up. The Scoliosis Research Society global satisfaction scale was 4.6 ± 0.2. No major complications were observed.

CONCLUSIONS

This technique yielded satisfactory clinical results in the treatment of L5-S1 spondyloptosis, resulting in stable anterior support and complete radiographic fusion. It avoided the complications reported from the use of previous posterior techniques such as graft fractures, pseudarthrosis, slip progression, and neurologic injuries.

In situ posterolateral and fibular interbody fusion in high grade spondylolysthesis

OBJECTIVE

High-grade spondylolysthesis and spondyloptosis management have various options. There were no large series reported to support any particular treatment modality. The aim of surgery is to get solid bony fusion to get relief of instability and its symptoms as well as relief of neurological symptoms. There are many treatment options which are associated with technical difficulties and high incidence of complications and failures. In situ transsacral fibular graft with posterolateral fusion along with posterior decompression is a good surgical option. It offers anterior and posterolateral fusion for instability pain and relief of neurological symptoms in most of the patients. It is technically simple, with no major surgery-related complications.

MATERIALS AND METHODS

The cases of high-grade spondylolysthesis operated since 2008 with one year minimal follow up were included in this study. Six cases were operated during this period. All were females in their second and third decade of life. All of them had transsacral fibular grafting with posterolateral fusion and decompression. One of the cases had additional anterior procedure with sacral widening with bone graft. The clinical status and bony fusion has been assessed at the end of one year after surgery and also for assessing final outcome.

RESULTS

All the patients had solid bony fusion with no progression of slip and are pain free and relived of neurological symptoms. conclusions: In situ transsacral fibular graft with posterolateral fusion and posterior decompression is technically simple surgical option with minimal risks and reliable outcome.

Surgical treatment of low-grade isthmic spondylolisthesis with transsacral fibular strut grafts

BACKGROUND

The ideal surgical treatment for adult low-grade isthmic spondylolisthesis (ALIS) remains unknown. Isolated anterior and posterior procedures are popular but have resulted in equivocal outcomes, whereas combined anterior and posterior procedures are associated with higher complication rates despite improved outcome.

OBJECTIVE

To evaluate the clinical and radiographic outcomes following the treatment of ALIS using a 1-stage posterior approach with posterior decompression and posterolateral arthrodesis combined with an interbody fibular allograft strut.

METHODS

Fifteen patients underwent fusion by a single surgeon using our modified technique. Seven patients were female and 8 were male, with a mean age of 48 years. All patients were classified as Meyerding grade II slips and underwent a posterior approach only, a decompressive laminectomy, and a circumferential fusion with the use of a transsacral fibular allograft and a posterolateral instrumented fusion. Postoperative clinical and radiographic evaluations were performed at 3, 6, and 12 months, and then on an annual basis.

RESULTS

The average follow-up interval was 61 months. Three complications were seen: a single dural tear, an L5 radiculopathy secondary to a malpositioned pedicle screw, and one patient with urinary retention. The spines of all patients were determined to be fused by the 6-month postoperative visit. All patients returned to their normal activities of daily living. Significant improvements in the visual analog score were seen at all follow-up intervals.

CONCLUSION

Transsacral interbody fibular allograft can be used successfully to supplement a posterolateral instrumented fusion in selected patients with low-grade ALIS.

Lumbosacral spondyloptosis treated using partial reduction and pedicular transvertebral screw fixation in an osteoporotic elderly patient

Spondyloptosis is complete dislocation of the L-5 vertebral body on the sacrum anteriorly. Its optimal treatment is still controversial. In particular, choosing the optimal surgical technique is difficult in the osteoporotic elderly patient given the high incidence of instrumentation failure, pseudarthrosis, progressive slippage, and severe sagittal imbalance. The authors of this report used partial reduction and pedicular transvertebral screw fixation of the lumbosacral junction for the treatment of spondyloptosis in an osteoporotic elderly patient.

A new three-stage spinal shortening procedure for reduction of severe adolescent isthmic spondylolisthesis: a case series with medium- to long-term follow-up

STUDY DESIGN

A case series of eight consecutive patients with severe (Meyerding Grade ≥ 3) adolescent isthmic spondylolisthesis (SAIS) who underwent reduction and stabilization by using a new surgical technique.

OBJECTIVE

To report the results of a safe three-stage spinal shortening procedure in a single operative session in eight patients with SAIS.

SUMMARY OF BACKGROUND DATA

The treatment of SAIS is controversial and the opinion continues to remain divided between in situ fusion and reduction followed by stabilization. We reported a new surgical technique to facilitate safe reduction and stabilization of SAIS and the results in eight adolescents are presented.

METHODS

Eight patients with Meyerding Grade III (2), IV (5), and V(1) were operated between 2000 and 2006 for SAIS. The back/leg pain duration was 13.7 months and average age at surgery was 14.75 years. The slip angle (SA), percentage slip (%S), sacral inclination (SI), lumbar lordosis (LL), pelvic incidence (PI), and sagittal balance were measured and the Oswestry Disability Index (ODI) and visual analog scale pain score were used as outcome measures. All patients underwent posterior decompression with sacral dome osteotomy, anterior transperitoneal L5/S1 discectomy, and posterior reduction and instrumented circumferential fusion in a single operative session.

RESULTS

The average follow-up was 6 years. The mean preoperative degree of slip was 86%, which improved to 5% (r 1-17%, spondyloptosis case 32%) postoperatively. The mean L5 SA, SI, and LL preoperatively were 48°, 34°, and -72°, respectively, and postoperatively improved to 43° and -47°, respectively. The sagittal balance was 55 and 34 mm pre- and postoperatively, respectively. Near anatomical reduction was achieved in seven patients. No implant failures or revisions to date. The mean ODI improved to 6% from 56% and visual analog scale from 8 to 1, postoperatively.

CONCLUSION

This safe 3-stage procedure assists sudden reduction and circumferential fusion of SAIS without any neurologic deficit and excellent clinicoradiologic outcome restoring normal lumbosacral biomechanics.

A modified technique for dowel fibular strut graft placement and circumferential fusion in the setting of L5-S1 spondylolisthesis and multilevel degenerative disc disease

BACKGROUND

Traditional techniques for the treatment of isthmic spondylolisthesis pass a fibular dowel graft across the L5-S1 disc by using the anterior portion of the L5 body.

OBJECTIVE

To introduce a technique for the treatment of isthmic spondylolisthesis in the setting of multilevel degenerative disc disease in adults. Our modified technique allows us to traverse the L5-S1 disc via the L4-5 disc space thereby treating the degenerated disc at L4-5 simultaneously.

METHODS

A standard anterior discectomy was performed on L4-5. Using biplanar fluoroscopy, a Kirschner wire was placed beginning at the anterior third of the L5 superior endplate and ending at S1. An anterior cruciate ligament reamer was used to make a channel for the fibular allograft. Then, a femoral ring allograft was placed in the disc space at L4-5, and standard anterior lumbar interbody fusions were performed at any additional cephalad level(s). Afterward, posterior instrumented fusion was performed to complement the anterior fusion procedure (except at L5), and wide decompression followed.

RESULTS

All patients presented with isthmic spondylolisthesis and all had multilevel fusions. The mean slip angle was 32.6 degrees (37.8 degrees preoperatively), and mean lumbar index was 67%. After the procedure, the average endplate-to-dowel angle was 107.1 degrees compared with 134 degrees. All patients had clinical and radiographic evidence of solid fusion without the need for revisions.

CONCLUSION

The proposed advantage of our modified technique is twofold. The graft is placed nearly perpendicular to the L5-S1 interface, as it will behave more efficiently with respect to interfragmental compression. Also, surgeons gain access to fuse L4-5 anteriorly and posteriorly.

Transsacral screw fixation for high-grade spondylolisthesis

BACKGROUND CONTEXT

Symptomatic high-grade spondylolisthesis (Meyerding III-V) is usually treated by surgery. Recent literature shows that in situ fusion is better than reduction of the slip and fusion in high-grade spondylolisthesis. Furthermore, the outcome is improved if circumferential fusion is performed in severe spondylolisthesis. We have performed a new technique of circumferential fusion in high-grade spondylolisthesis using two transsacral hollow modular anchorage (HMA) screws supplemented with pedicle screw fixation and posterolateral fusion.

PURPOSE

The aim of the study is to analyze the results of circumferential fusion using transsacral HMA screws supplemented with posterolateral fusion and pedicle screw fixation.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

Twelve patients with high-grade spondylolisthesis were reviewed.

OUTCOME MEASURES

Outcome was measured using short form 36 (SF-36) and the ability to return to work at the most recent follow-up.

METHODS

All patients had interbody fusion using transsacral HMA screws filled with cancellous bone graft and supplemented with pedicle screw instrumentation and posterolateral fusion.

RESULTS

The male to female ratio was 2:1 with a mean age of 31 years (range 13-54 years). Eleven of 12 patients had disappearance of leg pain. There were no neurological complications in any of them. Circumferential fusion was achieved in all of them at a mean follow-up of 21 months. The average physical function score improved from 22.50+/-10.34 to 57.50+/-17.39 (p=.001, 95% confidence interval [CI] -44.48 to -25.52), whereas the average pain score improved from 22.22+/-13.40 to 61.11+/-15.35 (p=.001, 95% CI -51.12 to -26.66).

CONCLUSIONS

HMA screws avoid the complications associated with autologous cortical fibular strut graft and also are useful to promote interbody fusion, as the hollowness in the screw can be filled with cancellous bone graft that helps in better fusion. Supplementary pedicle screw fixation is necessary to protect the HMA screws, and they together give a stable construct that can achieve a circumferential fusion in high-grade spondylolisthesis.

Transvertebral Transsacral strut grafting for high-grade isthmic spondylolisthesis L5-S1 with fibular allograft

STUDY DESIGN

A clinical retrospective study was conducted.

OBJECTIVE

To evaluate the clinical and radiographic outcomes of 25 consecutive patients with symptomatic high-grade isthmic spondylolisthesis at L5-S1 treated by decompression and transvertebral, transsacral strut grafting with fibular allograft.

SUMMARY OF BACKGROUND DATA

Symptomatic high-grade isthmic spondylolisthesis serves as a challenging clinical problem. Traditional treatment by in situ posterolateral arthrodesis has been associated with pseudarthrosis rates up to 50%. Even with successful posterolateral fusion, the graft is in an unfavorable biomechanical environment, owing to it being under tension, which can allow for progression of lumbosacral kyphosis (slip angle) and sagittal translation (slip). Open reduction of spondylolisthesis improves the biomechanical situation by allowing a trapezoidal interbody graft at L5-S1, but is associated with neurologic deficits in up to 30% of patients. The technique used in this particular study achieves the biomechanical goal of a structural interbody construct without the necessity of anatomically reducing the translational slip. The fibular strut grafts were placed through an anterior approach as part of an anterior/posterior procedure, or via a posterior approach as part of a posterior-only procedure.

METHODS

A consecutive series of 25 symptomatic patients with high-grade isthmic spondylolisthesis at L5-S1 had an average age of 29.8 years. Six patients were 16 years or younger. Eight patients underwent a posterior-only approach with posterior transosseous fibular strut grafting across S1 into the L5 vertebral body combined with posterolateral arthrodesis L4-S1 using a pedicle screw-rod construct. Seventeen patients underwent a combined anterior/posterior approach with transosseous fibular allograft strut grafting at L5-S1 and L4-L5 interbody arthrodesis using a femoral ring allograft supplemented with L4-S1 posterior pedicle screw-rod instrumentation. No reduction attempts were performed, other than those occurring spontaneously by patient positioning and decompression. Patients were evaluated for clinical improvement and radiographically. Clinical outcomes were measured with the scoliosis research society outcome instrument. Radiographs were followed for arthrodesis, translation, and slip angle. Mean follow-up was 39 months (range, 30 to 71 mo). All patients preoperatively had a grade III to V slip using the Meyerding classification (mean 3.7). The slip angle averaged 37 degrees.

RESULTS

The postoperative mean slip grade was 3.5 compared with 3.7 preoperatively (no significant difference). The mean slip angle improved to 27 degrees (8 to 40 degrees) postoperatively from 37 degrees (13 to 51 degrees) preoperatively (P<0.05). All patients went on to a stable arthrodesis, with no progression in slip or slip angle. There were no permanent neurologic deficits among any of the subjects, and all patients demonstrated improvement in their preoperative gait disturbance. Scoliosis research society functional outcome score showed 24/25 extremely satisfied or somewhat satisfied at latest follow-up.

CONCLUSIONS

Treatment by this method showed improvement in lumbosacral kyphosis while avoiding the neurologic injury risk associated with open slip-reduction maneuvers. Despite no reduction in translational deformity, this technique offers excellent fusion results, good clinical outcomes, and prevents further sagittal translation and lumbosacral kyphosis progression.

Anterior transvertebral interbody cage with posterior transdiscal pedicle screw instrumentation for high-grade spondylolisthesis

✓Adult high-grade degenerative spondylolisthesis represents the extreme end of the spectrum for spondylolisthesis and is consequently rarely encountered. Surgical management of high-grade spondylolisthesis requires constructs capable of resisting the shear forces at the slipped L5–S1 interspace. The severity of the slip, sacral inclination, and slip angle may make conventional approaches to 360° fusion difficult or hazardous. Transdiscal pedicle screw fixation, transvertebral fibular graft fusion, and transvertebral cage fixation are techniques that have been developed to establish anterior column load sharing and to resist shear forces at the L5–S1 interspace, given the anatomical constraints accompanying high-grade spondylolisthesis. In this technical note the authors describe the procedure for implanting an in situ anterior L5–S1 transvertebral cage and performing L4–5 anterior lumbar interbody fusion, followed by placement of posterior S1–L5 vertebral body transdiscal pedicle screws for management of high-grade spondylolisthesis.

Reduction of severe adolescent isthmic spondylolisthesis: a new technique

STUDY DESIGN

The case of a 14-year-old boy with a severe-grade isthmic spondylolisthesis who underwent reduction and stabilization using this technique is described.

OBJECTIVE

To report a new sequential 3-stage procedure for reduction and stabilization of severe adolescent isthmic spondylolisthesis during 1 operative session.

SUMMARY OF BACKGROUND DATA

Conventional reduction techniques do not address the important regional anatomic restraints on the L5 nerve root during the reduction maneuver, thereby leading to a high risk of neurologic deficit. Using certain technical refinements could reduce the risk of neurologic deficit. A literature review of reduction of high-grade spondylolisthesis and details of the technique are presented.

METHODS

We describe a new 3-stage procedure in a 14-year-old boy who presented with persistent mechanical low back pain, bilateral buttock and leg pain secondary to a severe-grade L5/S1 isthmic spondylolisthesis. Radiologic investigations, including plain radiographs and computerized tomography confirmed the diagnosis. Magnetic resonance imaging showed reduction of signal intensity in the disc at the L5/S1 level. We describe the 3 stages of this technique, which can provide complete sagittal correction. The technical variations to allow a safe reduction of the spondylolisthesis are illustrated.

RESULTS

This new procedure can achieve almost complete reduction of severe grades of L5/S1 spondylolisthesis, leading to an excellent cosmetic result and also considerably reduces the risk of neurologic deficit.

CONCLUSIONS

In severe-grade lumbosacral spondylolisthesis, isolated posterior fusion, even when supplemented with internal fixation, is not sufficient to prevent deformity progression. Therefore, a combined anterior and posterior fusion is necessary. Reduction of the deformity leads to restoration of normal sagittal alignment with an excellent cosmetic result. Reduction without release of posterior structures may lead to neurologic deficit. This 3-stage shortening procedure can provide sudden reduction of deformity with minimal risk of neurologic deficit. The procedure is technically demanding, and should be performed by spinal surgeons who are familiar with the principles of anterior and posterior fusions.

Evaluation and management of high-grade spondylolisthesis in adults

STUDY DESIGN

A retrospective review was performed on 21 adult patients surgically treated with high-grade spondylolisthesis (Grade III, IV, or V). Additionally, the natural history, classification, and surgical alternatives for high-grade spondylolisthesis in the adult are discussed through literature review.

OBJECTIVES

The purpose of this article is to review the clinical and radiographic outcomes of surgical treatment of high-grade spondylolisthesis in the adult from a single institution. The natural history and treatment options for these adults are described in this review.

SUMMARY OF BACKGROUND DATA

High-grade spondylolisthesis is typically diagnosed and treated in the child or adolescent. Most patients with high-grade spondylolisthesis received surgical treatment during their adolescence. Some patients, however, remain minimally symptomatic for life without surgery. Little has been written on the natural history or treatment of adults with high grades of spondylolisthesis. Most of the published reports on the surgical treatment of high-grade spondylolisthesis pertain to skeletally immature patients and maybe include a few adults in their series. Nonetheless, the different techniques of surgical treatment for high-grade spondylolisthesis that have been described in these studies can help the spinal surgeon in treatment options for this rare but difficult spinal deformity.

METHODS

A literature review of the published manuscripts on the treatment of high-grade spondylolisthesis was performed with particular attention to the natural history and surgical treatment involving adult patients. Adult patients (older than 21 years) with high-grade spondylolisthesis treated surgically were retrospectively reviewed. Patients' clinical charts and radiographs were reviewed before and after surgery. Determination of fusion success, clinical outcome, and complications were performed.

RESULTS

Twenty-one consecutive adults with high-grade spondylolisthesis who underwent lumbar spinal surgery were review retrospectively between 1990 and 2004. There were 13 females and 8 males with an average age of 35 years (range, 21-68 years). The average follow-up was 6.6 years. There were 11 Grade III, 6 Grade IV, and 4 Grade V slips, including 4 acquired and 17 developmental spondylolistheses. There were no pseudarthroses or significant instrumentation failures. There was 1 case of a complete cauda equina syndrome on a patient with preoperative symptoms of an incomplete cauda equina syndrome.

CONCLUSIONS

Adult patients with high-grade spondylolisthesis not responding to nonoperative treatment can be stabilized in situ with posterior instrumentation from L4 to S1. The use of adjunctive fixation with iliac screws and/or transvertebral screws is recommended for the adult patient, particularly in revision or unstable cases. Reduction of the slipped vertebrae remains controversial for all grades of spondylolisthesis and more so for the adult patient. Partial reduction of the slip angle, decreasing the lumbosacral kyphosis, should be considered if significant sagittal malalignment is present or to improve arthrodesis success. Anterior column support should be performed, particularly when reduction has been obtained. Anterior column support can be performed, anteriorly or posteriorly, either by using inter vertebral body structural strut support or with a transsacral fibular dowel to improve stability and success of arthrodesis.

Low-back pain in athletes

While most occurrences of low-back pain in athletes are self-limited sprains or strains, persistent, chronic, or recurrent symptoms are frequently associated with degenerative lumbar disc disease or spondylolytic stress lesions. The prevalence of radiographic evidence of disc degeneration is higher in athletes than it is in nonathletes; however, it remains unclear whether this correlates with a higher rate of back pain. Although there is little peer-reviewed clinical information on the subject, it is possible that chronic pain from degenerative disc disease that is recalcitrant after intensive and continuous nonoperative care can be successfully treated with interbody fusion in selected athletes. In general, the prevalence of spondylolysis is not higher in athletes than it is in nonathletes, although participation in sports involving repetitive hyperextension maneuvers, such as gymnastics, wrestling, and diving, appears to be associated with disproportionately higher rates of spondylolysis. Nonoperative treatment of spondylolysis results in successful pain relief in approximately 80% of athletes, independent of radiographic evidence of defect healing. In recalcitrant cases, direct surgical repair of the pars interarticularis with internal fixation and bone-grafting can yield high rates of pain relief in competitive athletes and allow a high percentage to return to play. Sacral stress fractures occur almost exclusively in individuals participating in high-level running sports, such as track or marathon. Treatment includes a brief period of limited weight-bearing followed by progressive mobilization, physical therapy, and return to sports in one to two months, when the pain has resolved.

Transvertebral interbody cage and pedicle screw fixation for high-grade spondylolisthesis. Case report

Surgical stabilization of high-grade lumbosacral spondylolisthesis is clinically challenging, and the success of deformity reduction and fusion varies. The authors describe a patient with Grade III spondylolisthesis at L5-S1. Partial reduction was achieved and fusion involved pedicle screw fixation and a posterior transvertebral interbody cage. This patient had developed progressive spondylolisthesis after decompression and posterolateral fusion for L5-S1 spondylolisthesis failed. Clinical and early radiographic results were excellent. Transsacral cage fixation can be considered a viable option to buttress the region in which high-grade L5-S1 spondylolisthesis has been reduced. The cage provides substrate for interbody arthrodesis and acts as a biomechanical stabilizer that helps prevent pedicle screw failure.

Transdiscal L5-S1 screws for the fixation of isthmic spondylolisthesis: a biomechanical evaluation

The current study is a biomechanical study using a cadaveric model of L5-S1 spondylolisthesis. The purpose of the current study was to compare, in a cadaveric model of simulated L5-S1 spondylolisthesis, the biomechanical stiffness of transdiscal fixation with traditional pedicle screw fixation, and transdiscal fixation with combined interbody/pedicle screw fixation. The surgical management of L5-S1 spondylolisthesis is a challenge because of the difficulties in achieving a reliable arthrodesis in the face of high mechanical forces. A method of lumbosacral fixation that has been used successfully in moderate grades of spondylolisthesis at our institution involves the use of transdiscal S1 pedicle screws. With this technique, S1 pedicle screws are placed through the S1 pedicle, through the superior endplate of S1, through the inferior endplate of L5, to terminate in the L5 body. Eighteen fresh human cadaveric (age 59-88 years) L5-S1 motion segments were obtained. The end of each intact motion segment was potted up to its midbody in a 10-cm-diameter polyvinylchloride end-cap using dental cement. The intact specimen was then biomechanically tested as follows: 1) axial compression (500 N), 2) flexion (10 Nm), 3) extension (10 Nm), 4) right lateral bending (10 Nm), and 5) left lateral bending (10 Nm). Stiffness values were calculated from the load-deflection curves obtained. Spondylolisthesis was then simulated by displacing L5 on S1 (% slip average = 41.3%) after performing a radical L5-S1 discectomy, L5 laminectomy, and bilateral L5-S1 facetectomies. The 18 motion segments were divided into two groups. Group I (n = 10) was biomechanically tested (as above) after pedicle screw fixation and again after replacing the S1 pedicle screws with transdiscal screws. Group II (n = 8) was biomechanically tested (as above) after combined interbody/pedicle screw fixation and again after fixation with transdiscal screws. Load-deflection curves were obtained each time, and stiffness values were calculated from the curves. Transdiscal fixation was 1.6-1.8 times stiffer than pedicle screw fixation (p < 0.05) in all loading modes tested. There were no differences in stiffness between transdiscal fixation and combined interbody/pedicle screw fixation. In a cadaveric model of simulated L5-S1 spondylolisthesis, transdiscal L5-S1 fixation produced a 1.6-1.8 times stiffer construct than traditional pedicle screw fixation. Further, the stiffness of the transdiscal fixation was equal to that of a combined interbody/pedicle screw fixation.

Colonic perforation complicating posteroanterior fusion using fibular strut autograft for a high-grade spondylolisthesis

Posteroanterior fusion using a fibular strut autograft has been advocated for the surgical treatment of high-grade lumbosacral spondylolisthesis. We report here the treatment of a 14-year-old girl using an S2-L5 fibular autograft, which resulted in the postoperative complication of a sigmoid colon perforation. Techniques for recognizing, treating, and avoiding this complication are presented.

Dowel fibular strut grafts for high-grade dysplastic isthmic spondylolisthesis

STUDY DESIGN

This is a clinical study that examines the results of partial reduction and fibular dowel graft placement for high-grade isthmic spondylolisthesis.

OBJECTIVES

To demonstrate the efficacy of partial reduction and fibular dowel graft placement in the treatment of high-grade isthmic spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Previous literature has demonstrated difficulty in treating high-grade isthmic spondylolisthesis both with high rates of pseudarthrosis as well as neurologic complications if a complete reduction is attempted. There are no published data examining partial reduction with dowel graft placement.

METHODS

Seventeen consecutive patients (mean age 20.3 years) with high-grade isthmic spondylolisthesis who were treated with posterior fusion and fibular strut grafts were studied (mean follow-up 4.6 years). Radiographs were reviewed at preoperative, immediate (within 3 months) postoperative, and ultimate (>2 years) follow-up. Parameters measured included lumbar lordosis, slip angle, Meyerding-Newman scores, and pelvic incidence. The anterior and posterior fusions were graded on a I-IV scale, and the implants (if used) were examined for failure. Clinical outcomes were measured with Oswestry and Scoliosis Research Society outcomes tools.

RESULTS

There were 17 patients treated: 10 primary and 7 revision patients. All patients had posterior fusion with fibular dowel grafts (11 allograft, 6 autograft). Meyerding grade improved 1.3 grades and slip angle improved 14 degrees with no loss of correction at ultimate follow-up. Sixteen of 17 patients had solid fusions on ultimate follow-up. Clinical evaluation with Scoliosis Research Society and Oswestry tools showed high patient function and satisfaction. Complications included one case of a broken strut in a revision patient; this was then revised to an instrumented circumferential fusion. There were no cases of deep or superficial infection. There were no neurologic deficits at ultimate follow-up.

CONCLUSION

Fibular strut grafting is a useful surgical adjunct in high-grade spondylolisthesis that is partially reduced. Clinical and radiographic outcomes were satisfactory. Our experience shows that there is no significant difference between allograft and autograft. All struts healed and remodeled by the ultimate follow-up, and there was only one instance of fibula fracture.

Circumferential fusion for spondylolisthesis in the lumbar spine

There are many options for the surgical treatment of lumbar spondylolisthesis, including anterior and posterior techniques. Among the most versatile is a 360° fusion. In consideration of the added risk of morbidity of two procedures, circumferential fusion leads to the highest fusion rates. This is particularly useful for patients at high risk for pseudarthrosis, such as patients with diabetes, posttransplant recipients, and those in whom fusion procedures have failed. Likewise, a 360° fusion may also be useful in achieving fusion in biomechanically disadvantageous situations, such as at the L5–S1 level or with high-grade subluxation. The options for 360° fusion are many and are determined, among other factors, by surgical pathology and surgeon preference. Standard open techniques are still considered the gold standard, although newer less invasive methods of circumferential fusion are being used more frequently. The operating surgeon must have a thorough knowledge of all available maneuvers for critical and effective decision making.

Partial lumbosacral kyphosis reduction, decompression, and posterior lumbosacral transfixation in high-grade isthmic spondylolisthesis: clinical and radiographic results in six patients

BACKGROUND

In an attempt to increase fusion while decreasing the neurologic risk associated with complete reduction of high-grade spondylolisthesis, the authors have used a technique of partial lumbosacral kyphosis reduction, posterior decompression, and pedicle screw transfixation of the lumbosacral junction.

OBJECTIVE

To determine if this technique is effective in treatment of high-grade spondylolisthesis.

STUDY DESIGN

A retrospective review of six patients with high-grade spondylolisthesis treated by this technique was performed. There were four female patients (ages 16 years [n=2], 23 years [n=1], and 29 years [n=1]) and two male patients (both 13 years of age) with spondylolisthesis ranging from Grade IV to Grade V. All patients presented with pain and radiculopathy. After surgery the patients were evaluated for resolution of symptoms, sagittal alignment, fusion, and satisfaction. The radiographic measurements included the slip angle, the percentage slip, and the sacral inclination. An SRS outcome score was also obtained on all six patients to evaluate postoperative outcome, in terms of pain control, self-image perception, and return to function.

RESULTS

The average length of follow-up was 42.6 months (range 24-60 months). All patients evidenced solid fusion by the 6-month follow-up (based on oblique radiographs showing lateral bridging bone masses). The slip angle was improved from 62 degrees to 28 degrees (P < 0.5), whereas there was no significant improvement in the percentage slip or the sacral inclination (89-80% and 28-37 degrees, respectively). No progression of the slip angle or percentage slip was noted on the follow-up radiographs. Complications included two intraoperative dural tears that were identified and repaired. There were no neurologic complications. The SRS outcome instrument demonstrated good postoperative pain control, function, self-image, and satisfaction in all patients.

CONCLUSION

In high-grade spondylolisthesis, this posterior approach is safe and effective in obtaining a solid arthrodesis, restoring sagittal balance, and improving function. These results reinforce the impression that it is the partial reduction of the slip angle, not the percentage slip, in high-grade spondylolisthesis that is important in obtaining optimal results.

Clinical outcome of trans-sacral interbody fusion after partial reduction for high-grade l5-s1 spondylolisthesis

STUDY DESIGN

A clinical retrospective study was conducted.

OBJECTIVE

To evaluate the clinical and radiographic outcome of reduction followed by trans-sacral interbody fusion for high-grade spondylolisthesis.

SUMMARY OF BACKGROUND DATA

In situ posterior interbody fusion with fibula allograft has improved the fusion rates for patients with high-grade spondylolisthesis. The use of this technique in conjunction with partial reduction has not been reported.

METHODS

Nine consecutive patients underwent treatment of high-grade (Grade 3 or 4) spondylolisthesis with partial reduction followed by posterior interbody fusion using cortical allograft. The average age at the time of surgery was 27 years (range, 8-51 years), and the average follow-up period was 43 months (range, 24-72 months). Before surgery, eight patients had low back pain, seven patients had radiating leg pain, and five patients had hamstring tightness. The average grade of spondylolisthesis by Meyerding grading was 3.9 (range, 3-5). Charts and radiographs were evaluated, and outcomes were collected by use of the modified SRS outcomes instrument.

RESULTS

Radiographic indexes demonstrated significant improvement with partial reduction and fusion. The slip angle, as measured from the inferior endplate of L5, improved from 41.2 degrees (range, 24-82 degrees ) before surgery to 21 degrees (range, 5-40 degrees ) after surgery. All the patients were extremely or somewhat satisfied with surgery. The two patients who underwent this operation without initial instrumentation experienced fractures of their interbody grafts. Both of these patients underwent repair of the pseudarthrosis with placement of trans-sacral pedicle screw instrumentation and subsequent fusion.

CONCLUSIONS

Partial reduction followed by posterior interbody fusion is an effective technique for the management of high-grade spondylolisthesis in pediatric and adult patient populations, as assessed by radiographic and clinical criteria. Pedicle screw instrumentation with the sacral screws capturing L5 is recommended when this technique is used for the treatment of high-grade spondylolisthesis. According to the clinical and radiographic results from this study, partial reduction and posterior fibula interbody fusion supplemented with pedicle screw instrumentation is an effective technique for select patients with high-grade spondylolisthesis at L5-S1.

Salvage reconstruction with vascularized fibular strut graft fusion using posterior approach in the treatment of severe spondylolisthesis

STUDY DESIGN

One case is reported in which a failed anterior fusion for Grade 4 spondylolisthesis was treated with a vascularized fibular strut graft using a posterior approach.

OBJECTIVES

To demonstrate the applicability of this technique for salvage cases or patients with systemic conditions that may decrease the success of more standard techniques.

SUMMARY OF BACKGROUND DATA

Surgical stabilization of spondylolisthesis through posterior approach with a fibular strut graft has been previously described. A vascularized strut graft can be used in the treatment of spondylolisthesis and may have applicability in those patients with underlying disease that may impair the use of more standard techniques or in salvage reconstruction.

METHODS

With the patient under general anesthesia, through a posterior approach S1 and L4 were decompressed. The fibula with its vascularity intact was harvested and anastomosed with the superior gluteal artery and vein. The fibular strut was placed into the space formed by reaming between L5 and S1. Ilial autograft was used to augment the posterior fusion. After the procedure the patient was placed in a hip spica cast.

RESULTS

At the 2-year follow-up the patient has incorporation of the graft, with no evidence of fracture and no significant progression of anterior slip.

CONCLUSION

A vascularized fibular strut graft is a feasible alternative in the treatment of severe spondylolisthesis. No complications were encountered in the involved patient. Future application may include salvage reconstruction of failed arthrodesis or in individuals with systemic conditions that may impair graft incorporation using more standard techniques.

Transvertebral pedicle fixation in severe grade spondylolisthesis. Report of three cases

The ideal treatment for spinal stabilization of Myerding Grade III-IV spondylolisthesis remains controversial, with a variety of techniques having been described. The authors report on a consecutive series of three adult patients with high-grade slippage who were treated with transvertebral pedicle fixation and standard spinal instrumentation, as both primary and revision procedures. There were no complications from the procedure, and a good outcome was achieved in all patients. The results at 4- to 8-year follow-up review are presented. This is a relatively simple and safe method of achieving spinal stabilization, which bypasses some of the problems caused by the associated anatomical distortion in high-grade spondylolisthesis and has good results at midterm follow up.

The axial cage. a pilot study for interbody fusion in higher-grade spondylolisthesis

BACKGROUND CONTEXT

The surgical treatment of high-grade spondylolisthesis is challenging. Posterolateral fusion alone has a high rate of pseudarthrosis. Surgical stabilization of higher-grade lumbar spondylolisthesis with a fibula strut graft is an effective technique but is associated with harvest site morbidity and graft fractures.

PURPOSE

We hypothesized that a lumbar interbody fusion with a long, threaded titanium cage, packed with cancellous bone, inserted across the center of the spondylolisthesis, would provide the rigid immobilization necessary for successful arthrodesis. This would, therefore, eliminate the need for fibula harvest and possibly reduce the need for posterior instrumentation.

STUDY DESIGN/SETTING

Prospective, study cohort of 11 consecutive patients with a minimum follow-up of 1 year.

PATIENT SAMPLE

Patients with higher-grade spondylolisthesis (grade II-IV) were considered eligible.

OUTCOME MEASURES

Pain was measured with a 10-point Numerical Rating Score (NRS). The Oswestry Disability Index (OSI) was used to assess patient function. Patients also responded to a satisfaction scale to evaluate satisfaction with their outcome. Radiographs were reviewed 1, 3, 6, 12, and, when available, 24 months after surgery.

METHODS

We reviewed our clinical results and technical outcomes in 11 consecutive patients who underwent this unique form of anterior lumbar interbody fusion with a custom axial cage.

RESULTS

There were no surgical or postoperative complications. Serial x-rays revealed no implant subsidence or loosening. There have been no implant fractures or reoperation. Clinical results have been excellent with significant pain reduction and improved function. At 1 year after surgery the mean NRS was 3.5 (range, 0-7), a significant average reduction of 5.0 points. (p<.001) All patients have been satisfied with their results.

CONCLUSIONS

The axial cage technique appears to be a significant improvement over the fibular strut graft for the treatment of higher-grade spondylolisthesis. It provides significant reduction in pain, significant improvement in function, high patient satisfaction, and avoids the morbidity and fracture risks associated with fibular strut grafting.

One-stage decompression and posterolateral and interbody fusion for severe spondylolisthesis. An analysis of 14 patients

STUDY DESIGN

A retrospective study of 14 patients with high-grade L5-S1 spondylolisthesis surgically treated with one-stage decompression and posterolateral and interbody fusion (technique of Bohlman and Cook).

OBJECTIVE

To determine the efficacy of this technique in managing severe lumbosacral spondylolisthesis.

SUMMARY OF BACKGROUND DATA

Controversy exists over the most appropriate method for managing high-grade spondylolisthesis. Circumferential in situ fusion from a single-stage posterior approach was described in 1982, but to the current authors' knowledge, there are not many reports on clinical results in the literature. The current authors studied 14 patients (mean age, 21 years) with severe L5-S1 spondylolisthesis. The percentage of slipping averaged 77%; slip angle averaged 36 degrees. The average follow-up period was 30 months. All patients had severe back or radicular symptoms. Two patients had foot drop, and four had minor neurologic dysfunction. Four patients had extremely tight hamstrings.

METHODS

Pre- and postoperative radiographic films and computed tomography scans were reviewed. Magnetic resonance imaging was carried out in 11 patients before surgery and at follow-up examination. Patients were evaluated for fusion rate, clinical outcome, and complications.

RESULTS

All six patients with motor deficit of the nerve roots showed complete strength recovery at follow-up examination. None of the patients had tightness of hamstrings. Twelve patients demonstrated incorporation of the graft with solid fusion, one patient had a fracture of the fibular graft, and one had graft resorption. All patients but one rated the surgical result as excellent. One patient was not satisfied with the cosmetic result. Transient paresthesias in the leg of the donor graft were documented in two patients.

CONCLUSIONS

Posterior decompression of the spinal canal combined with anterior and posterior arthrodesis performed at one stage through a posterior approach is a safe and effective technique for managing severe spondylolisthesis.

Traumatic open anterior lumbosacral fracture dislocation. A report of two cases

STUDY DESIGN

Case presentation.

OBJECTIVES

To review the diagnosis and treatment of rare anterior lumbosacral fracture dislocations.

SUMMARY OF BACKGROUND DATA

The severity of closed anterior and open and closed posterior lumbosacral dislocations has been documented; however, there have been no reports of open anterior lumbosacral dislocations in the literature. Two patients are reported who experienced acute open anterior lumbosacral fracture dislocations.

METHODS

Review of the patient history and physical examination, radiologic review, operative techniques, and a review of the literature.

RESULTS

Fractures healed in both patients, with no major infections. Both patients had persistent neurologic deficits at last follow-up.

CONCLUSIONS

Open lumbosacral fracture dislocations are complex injuries that require diligence on the part of the surgeons involved the recognize the severity of the injury, to prevent or resolve any infectious process, to prevent further neurologic injury, and then to obtain and maintain alignment of the spine on the pelvis.

Thoracic and lumbar deformity: rationale for selecting the appropriate fusion technique (Anterior, posterior, and 360 degree)

The rationale of anterior versus posterior, or combined fusion is discussed with regards to different clinical diagnoses and situations. Factors involved in the decision-making process include stability, magnitude of deformity, rigidity of deformity, neurologic considerations, bone quality, and medical/metabolic factors. Careful preoperative assessment and planning are required as well as consideration for the patient's overall well being.

Lumbar fusion results related to diagnosis

STUDY DESIGN

Pain outcome and functional outcome after primary lumbar fusion surgery were determined by a self-assessment questionnaire. The responses were correlated with various clinical parameters.

OBJECTIVES

To determine the result of fusion surgery among patients in various diagnostic groups using semiquantitative outcome scales.

SUMMARY OF BACKGROUND DATA

Most previous studies on the results of primary lumbar fusion have reported the presence of pain, but few have addressed function outcomes. Results of a literature review were inconclusive as to whether a patient's diagnosis is a predictor of improved results.

METHODS

During the 3-year period from 1988 to 1990, 165 patients underwent a primary lumbar fusion procedure. They had a chart and radiograph review and were categorized into five major diagnostic groups: 1) pediatric, 2) grade I-II spondylolisthesis (low-slip), 3) grade III-IV spondylolisthesis (high-slip), 4) degenerative disc disease, and 5) postdiscectomy. At a follow-up period of 5 years (mean) after the fusion, patients were mailed a questionnaire in which they described their pain and functional status before and after their lumbar fusion surgery. Questionnaires were returned by 92% of the patients. The questionnaire scores, complications, and revision procedures were grouped by patient diagnosis and analyzed.

RESULTS

Patient satisfaction with the results of primary lumbar fusion ranged from 69% (for the postdiscectomy group) to 100% (for the pediatric and high-slip groups). For all diagnostic groups, lumbar fusion resulted in a significant decrease in back pain and leg pain (visual analog scale), which was maintained throughout the follow-up period. For back pain, the pediatric and high-slip groups showed significantly more improvement than the degenerative disc disease or postdiscectomy groups. Leg pain among patients in the pediatric and high-slip groups was significantly more improved than leg pain among patients in the low-slip, degenerative disc disease, or postdiscectomy groups. There was no deterioration of pain scores during the follow-up period. After fusion, all groups had a significant decrease in Oswestry disability scores; patients in the pediatric and high-slip group had significantly more improvement than patients in the degenerative disc disease or postdiscectomy groups. High- and low-slip groups had a significant improvement in their pain drawing score. Medication use was substantially reduced in all groups. After fusion, a lack of improvement in back pain score or disability score was significantly correlated with pseudarthrosis.

CONCLUSIONS

The outcome of primary lumbar fusion surgery was decreased pain and increased function for the majority of patients in all five diagnostic categories. The amount of improvement varied by diagnostic group. Patients with developmental conditions showed greater improvement than patients with degenerative conditions.