Success and Failure of Percutaneous Minimally Invasive Direct Pars Repair: Analysis of Fracture Morphology

Pars Interarticularis Fractures Treated with Minimally Invasive Surgery: A Literature Review

Recurrent stress on the isthmic pars interarticularis often leads to profound injury and symptom burden. When conservative and medical management fail, there are various operative interventions that can be used. The current review details the common clinical presentation and treatment of pars injury, with a special focus on the emerging minimally invasive procedures used in isthmic pars interarticularis repair. PubMed and Google Scholar database literature reviews were conducted. The keywords and phrases that were searched include but were not limited to; "history of spondylolysis", "pars interarticularis", "pars defect", "conventional surgical repair of pars", and "minimally invasive repair of pars". The natural history, conventional presentation, etiology, risk factors, and management of pars interarticularis injury are discussed by the authors. The surgical interventions described include the Buck's repair, Morscher Screw-Hook repair, Scott's Wiring technique, and additional pedicle screw-based repairs. Minimally invasive techniques are also reviewed, including the Levi technique. Surgical intervention has been proven to be safe and effective in managing pars interarticularis fractures. However, minimally invasive techniques often provide additional benefit to patients such as reducing damage of surrounding structures, decreasing postoperative pain, and limiting the time away from sports and other activities.

Direct Pars Repair with Cannulated Screws in Adults: A Case Series and Systematic Literature Review

OBJECTIVE

Lumbar spondylolysis occurs in 5%-8% of adults. This study aimed to report clinical and radiographic outcomes of direct pars repair in adults with lumbar spondylolysis.

METHODS

We conducted a retrospective review of all patients treated for lumbar spondylolysis via open fracture reduction and direct pars repair with cannulated screws using a lag technique. Demographics, clinical presentation, perioperative and intraoperative imaging, and postoperative data were collected. We subsequently performed a systematic review to describe radiographic and clinical outcomes following direct pars repair.

RESULTS

Three patients were identified (mean age 40.3 years; range, 21-72 years; 2 male). All patients had bilateral L5 pars fractures treated via open, direct repair with cannulated screws. There were no intraoperative complications. Length of stay was <24 hours for each patient. All patients reported back/radicular symptom relief and returned to full-time manual labor by latest follow-up. Noncontrast lumbar computed tomography performed 14-20 months postoperatively confirmed that all patients had good bilateral screw placement without fracture. Two patients (21 and 28 years old at surgery) had evidence of fusion across fracture sites, while 1 patient exhibited radiolucency around the screws and no progression of spondylolisthesis. Additionally, we reviewed 8210 articles and included 15 in a systematic review of direct pars repair. Fusion rates were 67%-100%, with improved average Oswestry Disability Index and visual analog scale back pain scores by latest follow-up.

CONCLUSIONS

Lumbar spondylolysis treatment with open fracture reduction and direct pars repair with cannulated screws in adults is safe and may result in mechanical back/radicular pain relief, even in the absence of radiographic fusion.

Lumbar spondylolysis - Current concepts review

Lumbar pars interarticularis (PI) injury or spondylolysis occurs only in humans. This represents a stress fracture of the PI. Excessive loading in repetitive hyperextension is a significant risk factor and occurs most commonly at L5 followed by L4. It is bilateral in 80% of symptomatic cases but can be unilateral defect as well which runs a more benign course. Symptoms of low back pain relating to this lesion are more common in young athletes involved in trunk twisting sports. Like other stress fractures, the pain may come on abruptly or more insidiously over time and only related to certain activities. The pathologic progression starts with a stress reaction in the pars, progressing to an incomplete stress fracture, and then a complete pars fracture. Diagnosis is dependent on clinical examination and radiological imaging studies (plain radiography, computed tomography (CT) scans and magnetic resonance imaging (MRI) scans). Treatment is dependent on symptoms as well as radiographic stage of the lesion. Conservative management is the mainstay of treating early lesions. A comprehensive rehabilitation program incorporates core spinal stabilization exercises. Athletes should not return to sports until pain free. Professional sporting individuals are at increased risk of failure of resolution of symptoms that may require early surgical repair of the PI defect. Modified Buck's technique & pedicle screw-hook constructs for direct repair has a high success rate in patients who have persistent low back pain. Minimally invasive lumbar pars defect repair has given similar successful outcome with added advantage of minimizing muscle injury, preserving the adjacent joint and reduced hospital stay. Functional outcome is evaluated using the Visual Analogue Scale (VAS) for back pain, Oswestry Disability Index (ODI) and 36-Item Short-Form Health Survey (SF-36). Preoperative ODI and SF-36 physical component scores (PCS) are significant predictor of a good functional outcome.

Lumbar Spondylolysis Reconstruction-Stabilization Using a Motion-Preserving Technique

BACKGROUND

Conservative methods are the traditional options in the management of lumber spondylolysis whereas surgery is indicated for symptomatic patients not responding to medical treatment and cases with a multilevel pars defect. The aim of this prospective study was to evaluate the clinical, functional, and radiologic results of using bone graft and fixation with pedicular screw-rod-laminar hook construct in treatment of lumber spondylolysis.

PATIENTS AND METHODS

Between October 2017 and January 2020, 20 patients with symptomatic lumbar spondylolysis not responding to conservative treatment for more than 6 months were treated by defect reconstruction fixation using bone block autografting and pedicular screw laminar hook construct. The mean follow-up time was 12.5 ± 03.5 months. All patients were examined pre- and postoperatively and followed up clinically (pain [visual analog scale]), functionally (Oswestry Disability Index, Modified Prolo Functional Economic Scales, and Macnab criteria), and radiologically (pars defect healing). Perioperative outcomes and complications were documented.

RESULTS

Clinical, radiologic, and functional outcomes were significantly improved. Bony union was evident in all patients (100%). Blood loss, operative time, and hospital stay increased in cases with a multilevel pars defect and cases with associated injuries. Two cases reported complications in this study as misplaced pedicular screw and superficial wound infection.

CONCLUSIONS

Reconstruction fixation of pars defect using this construct is an effective, feasible procedure in the treatment of lumber spondylosis regarding the preservation of lumbar motion and avoidance of adjacent-segment problems after fusion.

Is there a place for surgical repair in adults with spondylolysis or grade-I spondylolisthesis-a systematic review and treatment algorithm

OBJECTIVES

Pars repair is less explored in adults due to associated disc degeneration with advancing age. The aim of our systematic review was to define optimal characteristics of adults with spondylolysis/grade-I spondylolisthesis suitable for pars repair and evaluate the feasibility, effectiveness, and safety of standard repair techniques in these adults.

METHODS

This systematic review is reported in line with PRISMA-P and protocol is registered with PROSPERO (CRD42020189208). Electronic searches were conducted in PubMed, Embase, Scopus, and Web of Science in June 2020 using systematic search strategy. Studies involving adults aged ≥18-years with spondylolysis/grade-1 isthmic spondylolisthesis treated with standard pars repair techniques were considered eligible. A two-staged (titles/abstracts and full-text) screening was conducted independently by three authors followed by quality assessment using the Joanna Briggs Institute critical appraisal checklist for selection of final articles for narrative synthesis.

RESULTS

A total of 5,813-articles were retrieved using systematic search strategy. First screening followed by removal of duplicates resulted in 111-articles. Second (full-text) screening resulted in exclusion of 64-articles. A final 47-articles were considered for data extraction after quality assessment. A total of 590-adults were enrolled across 47-studies; 93% were 'young adults' (18-35 years); 82% were males. Persistent low back pain was the common presenting complaint. Lysis defect was primarily bilateral (96.4%) and L5 was the most involved level (68.5%). Majority had no disc degeneration (83.5%) and had spondylolysis as the primary diagnosis (86%); only 14% had grade-I spondylolisthesis. Pars infiltration test was conducted in 22-studies and discography in 8-studies. Duration of prior conservative therapy was 3 to 72-months. Buck's repair was the commonest technique (27-studies, 372-adults). Successful repair was reported in 86% of patients treated with Buck's and ≥90% treated with Scott's, Morscher's and pedicle-screw-based techniques. Improvement in pain/functional outcomes, union rate and rate-of-return to sports/activity was high and comparable across all techniques. Intraoperative blood loss was low with minimally invasive versus traditional repair. The overall complication rate was 11.9%, with implant failure being the major complication.

CONCLUSIONS

Our systematic review establishes a definite place for lysis repair in carefully selected adults with spondylolysis/grade-I spondylolisthesis. We propose a treatment algorithm for optimizing patient selection and outcomes. We conclude that adults with age 18 to 45 years, no/mild disc or facet degenerative changes, positive diagnostic infiltration test, and normal preoperative discography will have successful outcomes with pars repair, regardless of the technique.

Minimally Invasive Approach Toward Percutaneous Direct Pars Repair: An Observational Study

BACKGROUND

Spondylolysis refers to a defect of the vertebral pars interarticularis. Percutaneous direct pars repair using a minimally invasive technique was performed in a group of young patients to maintain their spinal segment movement and to restore their normal anatomy. The aim of this study was to present the clinical, functional, and radiologic outcomes of pars defects that were repaired percutaneously via the minimally invasive technique.

METHODS

This was a single-center, nonrandomized, prospective study of the demographic, clinical, functional, and radiographic outcomes of 18 patients (age range, 18-32 years). The visual analog scale for back pain and the Oswestry Disability Index were used to evaluate the functional outcomes. The Macnab criteria were applied to evaluate patient satisfaction after surgery.

RESULTS

All patients were admitted with bilateral pars fracture at the level of L4 (n = 4) or L5 (n = 14). The average duration of clinical follow-up was 16.04 months (range, 12-28 months). With reference to the Macnab criteria, 17 patients (94%) showed perfect or good outcomes. Fusion or bridging of bones was observed on computed tomography in 14 patients (77%) at the last radiological examination.

CONCLUSIONS

Minimally invasive surgery to treat symptomatic spondylolysis is a safe option that minimizes muscle and soft tissue dissection. In this study, good clinical and functional outcomes were achieved in young patients with low complications and high fusion rates using completely percutaneous treatment.

Alleviation of Chronic Low Back Pain due to Bilateral Traumatic L4 Pars Interarticularis Fractures Relieved With Steroid Injections

Chronic back pain affects 20% of the adult population in the United States and is a significant source of disability and healthcare expenditure. One of the most common causes of chronic back pain is spondylosis. These changes result from age-related degeneration of the lumbar spine. As a result of this degeneration, spondylolisthesis can develop. Spondylolysis is a fracture of the pars interarticularis. It affects younger patients and is more prevalent in adolescents and elite athletes. It can be a debilitating condition that may force athletes into retirement as well as impair them with chronic pain and disability. Traditional treatment options include conservative management such as medications, rest, physical therapy, and rehabilitation. Surgery is reserved for patients who do not respond to conservative measures. Here we present the case of a 39-year-old mixed martial arts fighter with bilateral L4 pars interarticularis fractures and chronic low back pain. After failing conservative treatment options, this patient finally obtained significant relief with steroid injections at the level of the defect. The patient continues to do well with occasional injections and is able to maintain his mixed martial arts career. This case report provides evidence that injection therapy is a feasible alternative to surgery in patients who fail conservative therapy.