Repair Of Spondylolysis Research Articles

Direct Repair of Symptomatic Lumbar Spondylolysis Using Rod-Screw-Cable System

To assess the efficacy of a new direct lysis repair technique using internal fixation with rod, screws, and Songer cable in symptomatic lumbar spondylolysis. Between December 2015 and January 2020, patients who were diagnosed with symptomatic lumbar spondylolysis and surgically treated with a rod-screw-cable system were recruited. Pedicle screwing by the Magerl technique was performed in all included patients, followed by direct lysis repair with bone allograft and demineralized bone matrix by stabilizing the posterior lamina and spinous process using a rod-screw-cable system. Clinical outcome was measured using the visual analog scale and Oswestry disability index preoperatively and 6weeks, 3months, 6months, 1year, and 2years postoperatively. Sixteen patients were included in this study-11 men and 5 women (mean age: 47years; range, 26-67years). The lytic defects were at L4 and L5 in 6 and 10 patients, respectively. The mean follow-up period was 41months (24-62months). The visual analog scale values were 7.3, 6.1, 4.3, 3.3, 2.1, and 1.9 preoperatively and 6weeks, 3months, 6months, 1year, and 2years postoperatively, respectively. The Oswestry disability index values were 59.8%, 55.4%, 41.7%, 32.4%, 21.1%, and 16.9% for the same periods, respectively. No patient had an increase in the slip after surgery. There were no significant complications such as implant failure. Our technique provides rigid intra-segmental repair of spondylolysis without intersegmental motion interference, even if the patient is older or has disc degeneration.

Biomechanical evaluation of lumbar spondylolysis repair with various fixation options: A finite element analysis.

Objective: This study was designed to compare the biomechanical properties of lumbar spondylolysis repairs using different fixation methods by using three-dimensional finite element analysis. Methods: Five finite element models (A, B, C, D, and E) of L4-S1 vertebral body were reconstructed by CT images of a male patient (A: intact model; B: spondylolysis model; C: spondylolysis model with intrasegmental direct fixation by Buck screw; D: spondylolysis model with intersegmental indirect fixation by pedicle screw system; E: spondylolysis model with hybrid internal fixation). L5-S1 level was defined as the operative level. After the intact model was verified, six physiological motion states were simulated by applying 500N concentrated force and 10Nm torque on the upper surface of L4. The biomechanical properties of the three different internal fixation methods were evaluated by comparing the range of motion (ROM), maximum stress, and maximum displacement. Results: Compared with Model B, the ROM and maximum displacement of Model C, D, and E decreased. The maximum stress on L5/S1 disc in models A, B, and C was much higher than that in Model D and E under extension and lateral bending conditions. Under axial rotation and lateral bending conditions, the maximum stress of interarticular muscle and internal fixation system in Model B and Model C was significantly higher than that in Model D and Model E. In contrast to Model D, the stress in Model E was distributed in two internal fixation systems. Conclusion: In several mechanical comparisons, hybrid fixation had better biomechanical properties than other fixation methods. The experimental results show that hybrid fixation can stabilize the isthmus and reduce intervertebral disc stress, which making it the preferred treatment for lumbar spondylolysis.

Surgical repair of lumbar stress fractures in professional cricketers .

Professional cricket fast bowlers sustain high rates of lumbar stress fractures (spondylolysis). Limited research exists around the success of surgical repair when these injuries fail conservative treatment. We present an ambispective cohort study of spondylolysis surgical repair in a consecutive group of multi-national professional cricket fast bowler using a technique not previously reported in this unique sporting group. Between 2004 and 2019, a consecutive series of male professional fast bowlers with lumbar spondylolysis who had repeatedly failed conservative treatment and subsequently received surgical repair using a cable-screw construct were reviewed. Analysis comprised of ambispective outcome and radiological data collection and a survey at final follow-up. The cohort included 13 elite (7 state and 6 international) cricket fast bowlers from 3 countries (New Zealand, Australian and India) with an average age of 26 years (range, 20.3-29.5 years). All returned to play professional cricket at a median time of 8 months (IQR, 7-11 months) post surgery. All ten players surveyed at final follow-up [median, 38 (IQR, 31-103) months, range, 15-197 months] rated their bowling performance as the 'same or better' compared with prior to surgery. At final follow-up, 10 players continue to play cricket professionally ranging from 15 to 107 months post-surgery [median 35 (IQR, 24-43) months]. Our cohort demonstrated favorable return to play rates and career longevity following surgical repair of spondylolysis. To our knowledge it is the largest published surgical series of spondylolysis repair in cricketers, and the first to document the success of a cable-screw surgical technique in this sporting group.

Spondylolysis Repair Using a Minimally Invasive Modified Buck Technique with Neuronavigation and Neuromonitoring in High School and Professional Athletes: Technical Notes, Case Series, and Literature Review

Spondylolysis is a defect in the pars interarticularis of the vertebra that occurs frequently in high-performance young athletes. Although nonsurgical management is the mainstay of treatment, surgery is an option for patients with persistent symptoms despite multiple cycles of nonsurgical treatment. Performing a minimally invasive technique reduces complications, postsurgery pain, and hospitalization time and leads to a quick recovery. The aim of this study was to report the clinical results of a series of 3 patients treated with a modification of the Buck technique with a minimally invasive approach. Three high-performance athletes between 17 and 18 years old who were managed nonsurgically for at least 6 months underwent a modified Buck technique repair with a minimally invasive approach using cannulated compression screws, with neuronavigation and neuromonitoring. Patients were followed at least 6 months with computed tomography scans to assess consolidation and fixation status. Following rehabilitation and in the absence of pain, all 3 athletes returned to their respective sports. No complications were reported. All patients presented with bilateral spondylolysis, at L3 in 1 case and at L5 in 2 cases. Patients received conservative management for 12-36 months before surgery. After surgery, consolidation was obtained at 4 months in all patients, who returned to their sports activities in <6 months. The proposed technique shows the advantages of performing minimally invasive surgery in young high-performance athletes, ensuring consolidation and early return to sports activity without complications.

Repair of symptomatic bilateral L5 spondylolysis with autogenous iliac crest graft and temporary intersegmental pedicle screw fixation in youth

BackgroundWhen symptomatic spondylolysis fail to respond to nonoperative treatment, surgical management may be required. A number of techniques have been described for repair by intrasegmental fixation with good results; however, there are still some problems. We reported a repair technique with temporary intersegmental pedicle screw fixation and autogenous iliac crest graft. The aim of present study is to assess the clinical outcomes of L5 symptomatic spondylolysis with this technique.MethodsA retrospective analysis of 128 patients with L5 spondylolysis treated with this method was performed. According to CT scan, the spondylolysis were classified into 3 categories: line, intermediate, and sclerosis type. The diagnostic block test of L5 bilateral pars defect was done in all patients preoperatively. The sagittal and axial CT images were used to determine the bone union. The healing time, complications, number of spina bifida occulta, Japanese Orthopedic Association (JOA) score, and VAS for back pain were recorded. After fixation removal, the rate of ROM preservation at L5S1 was calculated.ResultsThere were 97 patients (194 pars) followed with mean follow-up of 23 months (range, 12–36 months). The union rate of pars was 82.0% at 12 months and 94.3% at 24 months postoperatively. Low back pain VAS significantly (P < 0.05) improved from preoperative mean value of 7.2 to 1.3 at the final follow-up postoperatively (P < 0.05). JOA score increased significantly postoperatively (P < 0.05) with average improvement rate of 79.3%. The rates of L5S1 ROM preservation were 79.8% and 64.0% after fixation removal at 1 and 2 years postoperatively. There were 3 patients of delayed incision healing without other complications.ConclusionsAlthough sacrificing L5S1 segment motion temporarily, more stability was obtained with intersegmental fixation. This technique is reliable for spondylolysis repair which has satisfactory symptom relief, high healing rate, low incidence of complications, and preserve a large part of ROM for fixed segment.

Direct reduction and repair of spondylolysis with grade 1 slip using the smiley face rod: a case report.

Objective: Lumbar spondylolysis, caused by stress fracture of the pars interarticularis may lead to a bony defect or spondylolisthesis. In adolescents, its surgical treatment employs the smiley face rod method for direct reduction of pseudoarthrotic spondylolysis and spondylolisthesis. Clinical outcomes of this treatment have been occasionally described; however, implant removal has not been discussed previously. We present a patient with lumbar spondylolysis with grade 1 slip at the 5th lumbar vertebra (L5) per the Meyerding classification.Patient: A 14-year-old boy presented with chronic severe lower back pain. Since conservative therapy did not resolve pain or enable resuming sports activities, the smiley face rod repair was performed 7 months after the initial treatment.Result: Anterior slippage of the L5 was surgically reduced. The patient wore a brace for 3 months postoperatively, and partial bone fusion was noted 6 months postoperatively. He resumed his sports activity 8 months postoperatively, and absolute bone fusion was confirmed 18 months postoperatively. Implant removal was performed 3 years postoperatively. Grade 1 slip was corrected with absolute bone fusion, and long-term follow-up revealed good results in terms of healing and rehabilitation.Conclusion: Smiley face rod method that allows for implant removal after bone fusion is suitable for adolescents.

Repair of spondylolysis using a pedicle screw U-shaped rod construct: A preliminary study of 25 young patients with a mean follow-up of 24 months.

Study Design:Prospective case series, therapeutic Level IV.Objectives:Functional and radiographic outcome evaluation of patients with spondylolysis treated with pars interarticularis defect repair with iliac bone grafting and application of a construct consisting of a pair of polyaxial pedicle screws connected by a U-shaped rod passing beneath the spinous process.Methods:Twenty-five patients (27 operated lumbar levels) with an average of 20 months of follow-up (range 12–24 m) with spondylolysis who met our inclusion criteria were treated with the above-mentioned technique. Functional assessment was by the Visual Analog Score (VAS) for low back pain (LBP) and Oswestry Disability Index (ODI). Fusion was confirmed with plain x-rays and when indicated with computed tomography scan. Return to activities of daily living (ADL) was also assessed.Results:There were 16 males (64%) and 9 females (36%), with a mean age of 18 ± 3 years at surgery, with a mean operating time of 79 ± 13 min and a mean blood loss of 186 ± 57 ml. ODI significantly improved from a mean of 63 ± 7 preoperatively to 10 ± 4 at 12 months postoperatively (P < 0.001). The mean preoperative LBP VAS score 8 ± 1 showed also a statistically significant decrease of values to 1 ± 1 at 12 months, (P < 0.001). At 12 m, all patients returned to unrestricted ADL. Pars healing was present in 19 patients (76%) at 6 months and in all patients at 12 months.Conclusions:Polyaxial pedicular screws with a U-shaped rod offer an effective and reproducible treatment for spondylolysis with an appropriate fusion rate, predictable return to daily activities, and good pain relief in young adults.

分離部修復にsmiley face rod変法が有用であったソフトボール選手の1例―術後の治癒過程の報告―

分離部修復にsmiley face rod変法が有用であったソフトボール選手の1例―術後の治癒過程の報告―

Spondylolysis repair using a pedicle screw hook or claw-hook system. -a comparison of bone fusion rates-

Introduction To assess the bone fusion rates and clinical results of two surgical methods (pedicle screw claw-hook fixation and pedicle screw hook fixation) of lumbar spondylolysis repair. Methods A multicenter database of surgical patients with lumbar spondylolysis was reviewed. All patients < 20 years old with a minimum of 6 months of follow-up and computed tomography images were included. Operation time and blood loss amount were investigated. Visual analogue scale (VAS; 0-10) scores for lower back pain were evaluated to assess clinical results. Results A total of 17 patients met the inclusion criteria. Pedicle screw hook fixation was performed in five patients (the hook group), and pedicle screw claw-hook fixation was performed in 13 patients (the claw-hook group). One patient was included in both groups because each method was performed at different lumbar levels (L4 and L5). The bone fusion rates at 3, 6, and 9 months after surgery were significantly higher in the claw-hook group than those in the hook group. Operation time and blood loss amount were not significantly different between the groups. VAS scores improved in the claw-hook group but not in the hook group because of a small number of patients. Conclusions Pedicle screw claw-hook fixation was more effective than pedicle screw hook fixation in terms of bone fusion rates.

Minimally-Invasive versus Conventional Repair of Spondylolysis in Athletes: A Review of Outcomes and Return to Play.

Spondylolysis from pars fracture is a common injury among young athletes, which can limit activity and cause chronic back pain. While current literature has examined the relative benefits of surgical and conservative management of these injuries, no study has yet compared outcomes between conventional direct repair of pars defects and modern minimally invasive procedures. The goals of surgery are pain resolution, return to play at previous levels of activity, and a shorter course of recovery. In this review, the authors have attempted to quantify any differences in outcome between patients treated with conventional or minimally invasive techniques. A literature search was performed of the PubMed database for relevant articles, excluding articles describing conservative management, traumatic injury, or high-grade spondylolisthesis. Articles included for review involved young athletes treated for symptomatic spondylolysis with either conventional or minimally invasive surgery. Two independent reviewers conducted the literature search and judged articles for inclusion. All studies were classified according to the North American Spine Society standards. Of the 116 results of our initial search, 16 articles were included with a total of 150 patients. Due to a paucity of operative details in older studies and inconsistencies in both clinical methods and reporting among most articles, little quantitative analysis was possible. However, patients in the minimally invasive group did have significantly higher rates of pain resolution (p<0.001). Short recovery times were also noted in this group. Both groups experienced low complication rates, and the majority of patients returned to previous levels of activity. Surgical repair of spondylolysis in young athletes is a safe and practical therapy. Current literature suggests that while conventional repair remains effective, minimally invasive procedures better clinical outcomes. We await further data to conduct a more thorough quantitative analysis of these techniques.

A minimal soft tissue damage approach of spondylolysis repair in athletes: preliminary report

Purpose and hypothesisBoth spondylolysis and spondylolisthesis come in second place in the causes of pain among athletes. Treatment options include both conservative management and different operative methods. Athletes and adolescents are groups where the priority is to protect tissues from perioperative damage.ObjectiveWe present our modification of the Buck’s, direct pars repair method, which we believe offers maximum protection of tissues. We used the modified surgical method in young, competitive athletes, in whom non-surgical treatment was not effective.MethodEight pars defects in five patients were treated using suggested method. All of them were young males (aged between 13 and 18 years), who practice soccer professionally. We use modified method of direct repair pars through the cannulated screw fixation, first proposed by Buck. Preoperative preparation consists of proper analysis of computer tomography images in multiplanar reconstruction mode: measuring screw length, measurement of inclination angle of the optimal screw trajectory in the frontal and sagittal plane. During the operation, the wire proper direction is performed by usage of the predetermined angles. Starting point for guide wire was also changed to the lower end of the facet. The fusion takes place with a screw of 3 mm diameter. After the operation patient need to use thoracolumbar spinal orthosis as a primary immobilization for 6 weeks and appropriate rehabilitation for another 6 weeks. We used these methods in eight pars fixations.ResultsAll of the patients were painless in first week after surgery. All of them underwent total rehabilitation programme and returned to sport.ConclusionsDirect pars repair using Buck’s method with proposed modification, including adequate radiographic preparation, the use of a thin cannulated screw and changing the point of screw entry, allows precise and safe screw placement, regardless of the size of the bone at the defect site.

Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

Prospective analysis. Our objective was to analyze clinical and functional results of patients with spondylolysis treated via direct intralaminar screw fixation and autograft, a minimally invasive and motion-preserving surgery. Spondylolysis is usually treated nonoperatively; multiple surgical techniques are available when nonoperative measures fail. No studies evaluate the clinical and functional outcomes and their correlation with pars defect size and disc morphology on magnetic resonance imaging. We reviewed patients with spondylolysis treated with intralaminar screw fixation and bone grafting from 2000 through 2010. Of the 31 patients (mean age, 16 yr; range, 10-37 yr), 25 (81%) were competitive athletes. Preoperative computed tomographic scans were used to measure the pars defect size, and preoperative magnetic resonance images were graded using Pfirrmann classification for correlation with postoperative outcomes. Student t test was used for analysis (significance, P < 0.05). At a mean follow-up of 60 months (range, 24-135 mo), pain (visual analogue scale score) significantly (P < 0.01) improved: preoperative mean, 7 points (range, 1-10 points); postoperative mean, 2 points (range, 0-10 points). Of the 25 athletes, 19 (76%) returned to competitive sports with a mean postoperative visual analogue scale score of 1 point (range, 0-4 points) at a mean of 6 months (range, 3-10 mo) after surgery. One patient required L6-S2 posterior spinal fusion after spondylolysis repair for persistent pain starting 18 months after intralaminar screw fixation, 2 patients sustained unilateral intralaminar screw fractures at L5, and 1 patient required irrigation and debridement for a superficial postoperative infection. There was no correlation among preoperative magnetic resonance imaging disc morphology, defect size on computed tomography, patient age, and clinical outcomes. Direct repair of spondylolysis with intralaminar screws offers a low profile, reliable treatment with good functional outcome and a low complication rate in active patients. 4.

Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

A biomechanical comparison of three spondylolysis repair techniques in a calf spine model

Previous work has demonstrated the efficacy of lumbar pedicle screw hook rod (PSHR) techniques and the Buck screw in the stabilization of spondylolysis. The mechanical behavior of lower profile cervical implants used to create PSHR, hybrid cable plate constructs, and titanium miniplating has not previously been described. Calf lumbar spines (L2-L6) were utilized for testing (n=27). Intervertebral rotation was measured in the intact spines across the L4-5 segment before and after creation of bilateral pars interarticularis defects. Defects were then stabilized with one of three repair techniques, PSHR, miniplate, or cable plate (CP) constructs. (n=9). A 5-Nm load was applied in flexion-extension, lateral bending and axial rotation. Fracture displacement was measured under flexion-extension and lateral bending modes. Osteotomy of the pars interarticularis increased intervertebral rotation from 4.6° to 9.2° (P<.05). The three techniques of repair reduced intervertebral rotation without statistical superiority of one method. In lateral bending the miniplate was most effective in reducing pars defect displacement (0.6mm, P<0.05). Although, the miniplate provided lower defect displacement in flexion-extension and axial rotation, these differences were not statistically significant. Bilateral miniplate fixation demonstrates superiority in restoring stability in lateral bending as compared to pedicle screw hook rod techniques and cable plate constructs. In flexion-extension and axial rotation, it was as effective as a PSHR method. Consideration of anatomic plate designs warrants consideration. IV.

Minimal access direct spondylolysis repair using a pedicle screw-rod system: a case series

IntroductionSymptomatic spondylolysis is always challenging to treat because the pars defect causing the instability needs to be stabilized while segmental fusion needs to be avoided. Direct repair of the pars defect is ideal in cases of spondylolysis in which posterior decompression is not necessary. We report clinical results using segmental pedicle-screw-rod fixation with bone grafting in patients with symptomatic spondylolysis, a modification of a technique first reported by Tokuhashi and Matsuzaki in 1996. We also describe the surgical technique, assess the fusion and analyze the outcomes of patients.Case presentationAt Cairo University Hospital, eight out of twelve Egyptian patients’ acute pars fractures healed after conservative management. Of those, two young male patients underwent an operative procedure for chronic low back pain secondary to pars defect. Case one was a 25-year-old Egyptian man who presented with a one-year history of axial low back pain, not radiating to the lower limbs, after falling from height. Case two was a 29-year-old Egyptian man who presented with a one-year history of axial low back pain and a one-year history of mild claudication and infrequent radiation to the leg, never below the knee. Utilizing a standardized mini-access fluoroscopically-guided surgical protocol, fixation was established with two titanium pedicle screws place into both pedicles, at the same level as the pars defect, without violating the facet joint. The cleaned pars defect was grafted; a curved titanium rod was then passed under the base of the spinous process of the affected vertebra, bridging the loose fragment, and attached to the pedicle screw heads, to uplift the spinal process, followed by compression of the defect. The patients were discharged three days after the procedure, with successful fusion at one-year follow-up. No rod breakage or implant-related complications were reported.ConclusionsWhere there is no evidence of frank spondylolisthesis or displacement and pain does not radiate below the knee, we recommend direct repair of the pars interarticularis fracture, especially in young active adults. We describe a modified form of the Buck screw procedure with a minimally invasive, image-guided method of pars interarticularis fixation. The use of image guidance simplifies the otherwise difficult visualization required for pars interarticularis screw placement and allows minimal skin and muscle dissection, which may translate into a more rapid postoperative recovery.

Clinical Results and Functional Outcomes After Direct Intralaminar Screw Repair of Spondylolysis

Spondylolysis is most often treated nonoperatively, but multiple surgical techniques have been described when nonoperative measures fail. Direct intralaminar screw fixation offers a minimally invasive and motion-preserving surgery.

Repair of Pars Defects by Segmental Transverse Wiring for Athletes With Symptomatic Spondylolysis

Retrospective study of surgery for spondylolysis patients. To assess clinical outcome of bony union using multislice computed tomography after segmental wiring fixation. How bony union affects surgical outcome of spondylolysis repair is unclear. Forty-four athletes with symptomatic spondylolysis (33 men and 11 women; mean age, 24.2 ± 5.4 years) who underwent segmental wiring fixation were evaluated retrospectively at a mean follow-up of 85 ± 17 months. The level of spondylolysis was L5 in 42 cases, and both L4 and L5 in 2 cases, giving a total of 46 operative levels of vertebrae. Bony union using axial and sagittal reconstruction images of computed tomography, the Japanese Orthopaedic Association (JOA) score for back pain, and complications were reviewed. State of bony union was classified as bilateral union, unilateral union, or nonunion. The total score and the improvement ratio of the JOA score were compared among the 3 groups. Bilateral bony union was obtained in 29 cases (31 of 46 vertebrae, 67.4%). Six cases (13%) showed unilateral union, and 9 cases (19.6%) showed nonunion. JOA score increased significantly after surgery in all groups, average improvement rate was 78.9% in the bilateral group, 63.6% in the unilateral group, and 29.8% in the nonunion group; differences among the 3 groups were significant (P < 0.05). JOA score was significantly higher in the bilateral group than in the other 2 groups. Although symptoms were significantly ameliorated in all groups, the bilateral group showed the greatest improvement ratio in JOA score showing bony union to be an important factor in clinical outcome. However, there were a few exceptional cases with contradictory clinical and radiological outcomes. Thus, further studies are required to gain a better understanding of the other multiple factors affecting clinical outcome after spondylolysis repair.

Direct surgical repair of spondylolysis in athletes: indications, techniques, and outcomes

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. 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. 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. 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.

2011 Showa Ika award Technique and results of “meshplating”, a method of spondylolysis repair for spondylolysis and spondylolytic spondylolisthesis

2011 Showa Ika award Technique and results of “meshplating”, a method of spondylolysis repair for spondylolysis and spondylolytic spondylolisthesis

Motion segment–sparing repair of symptomatic chronic pars defects

The current standard of care for symptomatic chronic spondylolysis (SP) is a one-level posterior spinal fusion for defects at L-5 or direct pars repair (motion segment sparing) for more rostral SP in younger patients and if no disc degeneration or listhesis is present. Since many patients with SP undergoing operative repair are young, a procedure with the lowest biomechanical profile is desirable, and direct pars repair is recommended. The authors here explore the limits of direct pars repair. A retrospective review of all patients who underwent direct repair of SP between 2002 and 2009 was performed. Data were analyzed for predictors of symptom relief and radiographic fusion failure. Of 49 patients, only 7 required a reoperation to treat clinical symptoms, and 6 of them were female (p = 0.049). In all cases of treatment failure, the patient had bilateral L-5 SP. Patients with a slip percentage as high as 30% experienced radiographic fusion and symptom relief. Disc degeneration (measured using the Modified Pfirrmann Scale) did not predict symptom persistence or radiographic fusion failure. Patients with high-grade disc disease experienced symptom relief. The authors found no predictors of treatment failure. The number of patients undergoing motion segment-sparing fusions of symptomatic chronic SP can be safely increased to include patients with Grade I spondylolisthesis as well as high-grade disc disease. Female patients with bilateral L-5 SP and low lordotic angles may be better served by a posterior spinal fusion from L-5 to S-1.