Management of lumbar spondylolysis in the adolescent athlete: a review of over 200 cases

Anatomical Parameters of Percutaneous, Minimally Invasive, Direct Intralaminar Pars Screw Fixation of Spondylolysis

OBJECTIVE

To investigate the anatomical parameters of the ideal screw trajectory for percutaneous intralaminar screw fixation of a pars defect in lumbar spondylolysis using computed tomography scans.

METHODS

Using advanced radiological software, the ideal intralaminar screw trajectory was determined. The anatomical parameters of this trajectory were analyzed using a total of 80 single-level lumbar tomography scans in patients with spondylolysis at the lumbar 4 vertebrae and lumbar 5 vertebrae levels. The ideal intralaminar screw trajectory started from the inferolateral edge of the lamina and was between the intralaminar region, pars defect, and defective pars neck and pedicle. Along this trajectory, the skin-lamina distance, intralaminar screw length, isthmic lamina length and width, defective pars neck width, lateral entry distance of the screw to the center of the spinous process, and sagittal and coronal screw application angles were analyzed.

RESULTS

When comparing the lumbar 4 vertebrae and lumbar 5 vertebrae parameters, the mean skin-to-lamina distances were 11-9 cm (P = 0.000), intralaminar screw lengths 3.5-3.6 cm (P = 0.067), isthmic lamina lengths 2-2 cm (P = 0.698), mid-lamina widths 1-1 cm (P = 0.941), defective pars neck widths 1-1 cm (P = 0.674), screw lateral entry distances according to the spinous process 1-1.5 cm (P = 0.000), sagittal screw angles 45°-45° (P = 0.870), and coronal screw angles 10°-20° (P = 0.000), respectively. There were no differences based on age and gender (P < 0.05).

CONCLUSIONS

Percutaneous intralaminar rigid screw fixation of a pars defect in spondylolysis provides minimally invasive, low-profile instrumentation. In spondylolysis, a screw length of 3-4 cm and a screw diameter of 4-5 mm may be sufficient for pars fixation with intralaminar screws.

The Method of Portal Making in Lumbar Unilateral Biportal Endoscopic Surgery with Different Operative Approaches According to the Constant Anatomical Landmarks of the Lumbar Spine: A Review of the Literature

STUDY DESIGN

Review.

OBJECTIVE

Unilateral Biportal Endoscopy (UBE) is a minimally invasive surgery that is gaining recognition and being employed in clinical practice. Nevertheless, the precise method for determining UBE portals' location varies depending on the originator's preferences or the anatomical structure's proximity to the portal positions. Consequently, the relationship among UBE portals' locations is messy. This study aims to elaborate on the specific portal localization and explore the positional association and commonality among different UBE approaches' portals.

METHODS

The following keywords are used to search in the PubMed, Ovid, Web of Science, ScienceDirect, SpringerLink, Scopus, CNKI, and Wanfang database: "Biportal endoscopic spinal surgery", "Two portal endoscopic spinal surgery", "Percutaneous biportal endoscopic decompression", "Unilateral biportal endoscopy", "Irrigation endoscopic discectomy", "UBE" and "BESS".

RESULTS

After screening, 29 pieces of literature are included. The study summarizes different UBE approach portal localizations, categorized by fusion or non-fusion surgery and pathological classification. The study presents an inaugural method for categorizing the lumber into four surgical intervals based on bone landmarks and assigns different UBE approaches to the appropriate intervals based on their characteristics, making the selection of UBE surgical approaches' portal locations more flexible. Additionally, the study provides an overview of the indications, complications, and distinct benefits associated with each interval, further refining the novel UBE portal interval localization method.

CONCLUSION

The study clarifies the interrelationship and commonality between the portals of different UBE approaches and proposes a new UBE portal interval localization method to enhance surgeons' understanding and proficiency in UBE procedures.

Long-term results and surgical strategy development for degenerative disease treatment in athletes: a retrospective single-center study

PURPOSE

To analyze of the results of spine surgical treatment of athletes with lumbar degenerative disease and development of a surgical strategy based on the preoperative symptoms and radiological changes in the lumbar spine.

METHODS

For 114 athletes with lumbar degenerative disease were included in the present study. Four independent groups were studied: (1) microsurgical/endoscopic discectomy (n = 35); (2) PRP therapy in facet joints (n = 41); (3) total disc replacement (n = 11); (4) lumbar interbody fusion (n = 27). We evaluated postoperative clinical outcomes and preoperative radiological results. The average postoperative follow-up was 5 (3;6), 3.5 (3;5), 3 (2;4) and 4 (3;5) years, respectively. The analysis included an assessment of clinical outcomes (initial clinical symptoms, chronic pain syndrome level according to the VAS, quality of life according to the SF-36 questionnaire, degree of tolerance to physical activity according to the subjective Borg Rating of Perceived Exertion Scale) and radiological data (Dynamic Slip, Dynamic Segmental Angle, degenerative changes in the facet joint according to the Fujiwara classification and disc according to the Pfirrmann classification; changes in the diffusion coefficient using diffusion-weighted MRI).

RESULTS

The median and 25-75% quartiles timing of return to sports were 12.6 (10.2;14.1), 2.8 (2.4;3.7), 9 (6;12), and 14 (9;17) weeks, respectively. We examined the type of surgical treatment utilized, as well as the preoperative clinical symptoms, severity of degenerative changes in the intervertebral disc and facet joint, the timing of return to sports, the level of pain syndrome, the quality of life according to SF-36, and the degree of tolerance to physical activity. We then developed a surgical strategy based on individual preoperative neurological function and lumbar morphological changes.

CONCLUSIONS

In this retrospective study, we report clinical results of four treatment options of lumbar spine degenerative disease in athletes. The use of developed patient selection criteria for the analyzed surgical techniques is aimed at minimizing return-to-play times.

Development and biomechanical analysis of an axially controlled compression spinal rod for lumbar spondylolysis

BACKGROUND

To elucidate the differences in mechanical performance between a novel axially controlled compression spinal rod (ACCSR) for lumbar spondylolysis (LS) and the common spinal rod (CSR).

METHODS

A total of 36 ACCSRs and 36 CSRs from the same batch were used in this study, each with a diameter of 6.0 mm. Biomechanical tests were carried out on spinal rods for the ACCSR group and on pedicle screw-rod internal fixation systems for the CSR group. The spinal rod tests were conducted following the guidelines outlined in the American Society for Testing and Materials (ASTM) F 2193, while the pedicle screw-rod internal fixation system tests adhered to ASTM F 1798-97 standards.

RESULTS

The stiffness of ACCSR and CSR was 1559.15 ± 50.15 and 3788.86 ± 156.45 N/mm (P < .001). ACCSR's yield load was 1345.73 (1297.90-1359.97) N, whereas CSR's was 4046.83 (3805.8-4072.53) N (P = .002). ACCSR's load in the 2.5 millionth cycle of the fatigue four-point bending test was 320 N. The axial gripping capacity of ACCSR and CSR was 1632.53 ± 165.64 and 1273.62 ± 205.63 N (P = .004). ACCSR's torsional gripping capacity was 3.45 (3.23-3.47) Nm, while CSR's was 3.27 (3.07-3.59) Nm (P = .654). The stiffness of the pedicle screws of the ACCSR and CSR group was 783.83 (775.67-798.94) and 773.14 (758.70-783.62) N/mm (P = .085). The yield loads on the pedicle screws of the ACCSR and CSR group was 1345.73 (1297.90-1359.97) and 4046.83 (3805.8-4072.53) N (P = .099).

CONCLUSION

Although ACCSR exhibited lower yield load, stiffness, and fatigue resistance compared to CSR, it demonstrated significantly higher axial gripping capacity and met the stress requirement of the human isthmus. Consequently, ACCSR presents a promising alternative to CSR for LS remediation.

The Classification of Lumbar Spondylolisthesis X-Ray Images Using Convolutional Neural Networks

We aimed to develop and validate a deep convolutional neural network (DCNN) model capable of accurately identifying spondylolysis or spondylolisthesis on lateral or dynamic X-ray images. A total of 2449 lumbar lateral and dynamic X-ray images were collected from two tertiary hospitals. These images were categorized into lumbar spondylolysis (LS), degenerative lumbar spondylolisthesis (DLS), and normal lumbar in a proportional manner. Subsequently, the images were randomly divided into training, validation, and test sets to establish a classification recognition network. The model training and validation process utilized the EfficientNetV2-M network. The model's ability to generalize was assessed by conducting a rigorous evaluation on an entirely independent test set and comparing its performance with the diagnoses made by three orthopedists and three radiologists. The evaluation metrics employed to assess the model's performance included accuracy, sensitivity, specificity, and F1 score. Additionally, the weight distribution of the network was visualized using gradient-weighted class activation mapping (Grad-CAM). For the doctor group, accuracy ranged from 87.9 to 90.0% (mean, 89.0%), precision ranged from 87.2 to 90.5% (mean, 89.0%), sensitivity ranged from 87.1 to 91.0% (mean, 89.2%), specificity ranged from 93.7 to 94.7% (mean, 94.3%), and F1 score ranged from 88.2 to 89.9% (mean, 89.1%). The DCNN model had accuracy of 92.0%, precision of 91.9%, sensitivity of 92.2%, specificity of 95.7%, and F1 score of 92.0%. Grad-CAM exhibited concentrations of highlighted areas in the intervertebral foraminal region. We developed a DCNN model that intelligently distinguished spondylolysis or spondylolisthesis on lumbar lateral or lumbar dynamic radiographs.

T1-VIBE and STIR MRI of lumbar pars interarticularis injuries in elite athletes: fracture characterisation and potential prognostic indicators

OBJECTIVES

To assess how pars interarticularis fracture characteristics on T1-VIBE and STIR MRI relate to healing and identify anatomical parameters that may impact healing.

MATERIALS AND METHODS

A retrospective review of an MRI series of lumbar pars interarticularis injuries in elite athletes over a 3-year period. Fracture configurations, signal intensities and anatomical parameters were recorded by two radiologists. Statistical analysis employed multilevel mixed-effects linear regressions, adjusted for repeated measures and baseline covariates.

RESULTS

Forty-seven lumbar pars interarticularis injuries among 31 athletes were assessed. On final scans for each athlete, 15% (7/47) injuries had worsened, 23% (11/47) remained stable, 43% (20/47) partially healed and 19% (9/47) healed completely. Healing times varied, quickest was 49 days for a chronic fracture in a footballer. Bone marrow oedema signal was highest in worsened fractures, followed by improved, and lowest in stable fractures. As healing progressed, T1-VIBE signal at the fracture line decreased. Bone marrow oedema and fracture line signal peaked at 90-120 days before decreasing until 210-240 days. Fractures with smaller dimensions, more vertical orientation and a longer superior articular facet beneath were significantly associated with better healing (p < 0.05).

CONCLUSION

Most diagnosed athletic pars interarticularis injuries improve. Normalising T1-VIBE signal at the fracture line is a novel measurable indicator of bony healing. Contrastingly, bone marrow oedema signal is higher in active fractures irrespective of healing or deterioration. Injuries initially perceived as worsening may be exhibiting the normal osteoclastic phase of healing. Better outcomes favour smaller, vertical fractures with a longer superior articular facet beneath.

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.

Characteristics of lumbar spondylolysis: L5 versus non-L5

BACKGROUND

Fifth lumbar vertebra (L5) spondylolysis has a lower bone union rate than non-L5 spondylolysis, but the reason for this is unknown. This study aimed to evaluate the differences in patient and lesion characteristics between L5 and non-L5 spondylolysis.

METHODS

A total of 410 patients with lumbar spondylolysis aged 18 years or younger who were treated conservatively were enrolled. Patients and lesions were divided into L5 and non-L5 (L2-L4) spondylolysis. Factors, including sex, age, presence of spina bifida occulta, stage of the main side lesion, whether the lesion was unilateral or bilateral, presence and stage of the contralateral side lesion and treatment duration, were evaluated at the first visit and compared between the two groups.

RESULTS

A total of 250 patients with 349 lesions were included. The bone union rate of L5 lesions was lower than that of non-L5 lesions (75% vs. 86%, p = 0.015). Patients with L5 spondylolysis were more likely to be male (86% vs. 66%) and younger (14.0 vs. 14.6 years) than patients with non-L5 spondylolysis. Lesions of L5 spondylolysis were more likely to be in a progressive stage (28% vs. 15%), less likely to be in a pre-lysis stage (28% vs. 43%) and more likely to be in a contralateral terminal stage (14% vs. 5.3%, p = 0.013) compared with lesions of non-L5 spondylolysis.

CONCLUSIONS

L5 spondylolysis was characterised by a lower bone union rate, more males, younger age, more progressive stage and more contralateral pseudarthrosis than non-L5 spondylolysis.

New technique and case report: Robot-assisted intralaminar screw fixation of spondylolysis in an adolescent

Introduction

Management of spondylolysis in adolescents is generally successful with conservative management. Uncommonly, surgical fixation is necessary for refractory cases. Direct repair with intralaminar screws is one commonly utilized technique. Recently, less invasive spinal procedures are becoming viable with the enabling of technologies, including robotics.

Case description

A 14-year-old baseball player and surfer presented with low back pain, diagnosed by MRI as bony edema and stress fractures of the posterior spinal elements. After 18 months, the pain was unresponsive to rest, physical therapy, and bracing. There was no radicular pain or neurologic symptoms. Computed tomography (CT) revealed bilateral, chronic nonhealing pars defects at L5. He underwent outpatient, robot-assisted percutaneous intralaminar fixation with hydroxyapatite-coated screws through a 2 cm skin incision.

Outcome

On postoperative day 1, the patient reported relief of his preoperative pain and he was ambulating without difficulty. At 2 weeks follow-up, the patient was completely pain free and surfing. At 2 months follow-up, low-dose CT demonstrated partial incorporation of the hydroxyapatite-coated screws, and the patient returned to sports. At 6 months follow-up, the patient had no pain and was swinging his baseball bat with full force. Low-dose CT revealed complete healing of the defects with full incorporation of the hydroxyapatite-coated screws.

Conclusions

A novel minimally invasive robotic percutaneous approach for direct spondylolysis repair using hydroxyapatite-coated screws is a potential surgical treatment option for non-healing pars defects in adolescent patients.

Management of low back pain accompanying sagittal plane pathologies in children: Spondylolysis/spondylolisthesis and Scheuermann's disease

Background

Low back pain in childhood was underappreciated for a long time, but recent studies report higher prevalences, up to 70%. Two of the common causes are spondylolyis/spondylolisthesis and Scheuermann's disease. These disorders are relevant in a way they both cause significant back pain, and may disrupt the sagittal spinal balance.

Purpose

To present the current evidence on the diagnosis, natural history and treatment of these disorders with a special focus on sagittal spinal alignment.

Methods

This study is conducted as a literature review.

Results and Conclusions

Spondylolysis and low-grade spondylolisthesis have a benign course and are typically treated conservatively. When pars repair is indicated, pedicle screw-based techniques achieve more than 90% fusion with acceptable complication rates. High-grade spondylolisthesis, however, is frequently progressive. Surgical treatment involves fusion, which can be done in situ or after reduction. Reduction is useful for "unbalanced" patients to acquire sagittal spinopelvic balance, and it is important to distinguish these patients. Despite lowering the risk for pseudoarthrosis, reduction brings a risk for neurologic complications. With re-operation rates as high as 40%, these patients definitely require careful preoperative planning. Scheuermann's disease generally causes back pain in addition to cosmetic discomfort during adolescence. If the kyphosis is lower than 60°, symptoms typically resolve into adulthood with conservative measures only. However, it must be kept in mind that these patients may experience problems with physical performance and have a lower quality of life even when the problem seems to have "resolved". Severe kyphosis and intractable back pain are the most frequently referred surgical indications, and surgery typically involves fusion. Proper utilization of osteotomies and proper selection of the upper and lower fusion levels are of utmost importance to prevent complications in these patients.

Clinical Outcomes of Isobar TTL System with Isthmic Bone Grafting and Pedicle Screw-Vertebral Plate Hook with Direct Repair of Defect for Lumbar Spondylolysis: A Matched-Pair Case Control Study

OBJECTIVE

Although direct isthmic repair, such as PSVPH, did not affect the mobility of the fixed segment and adjacent segment, it has a relatively low rate of isthmic fusion compared with conventional fusion. The Isobar TTL dynamic internal fixation system has been widely used in clinical practice and has achieved satisfactory clinical results. However, the use of the Isobar TTL system in combination with direct isthmic repair for lumbar spondylolysis has rarely been reported. The aim of this study was to compare the clinical and radiologic outcomes between patients who underwent Isobar TTL system and PSVPH with direct repair of defect for lumbar spondylolysis.

METHODS

Stepwise propensity score matching (PSM) for age and sex were performed to keep comparable clinical data between groups in this retrospective and matched-pair case control study. A total of 50 patients diagnosed with lumbar spondylolysis underwent surgical implantation of the Isobar TTL group (n = 25) or PSVPH group (n = 25) from June 2009 to June 2016. Clinical outcomes were assessed using the Oswestry disability index (ODI), and visual analog score (VAS). Radiographic evaluations included range of motion (ROM) and the disc heights of stabilized segment and adjacent segment, adjacent segment degeneration (ASD) and bony fusion. Three-dimensional reconstruction of lumbar CT scan was obtained to evaluate bone fusion of the isthmic at final follow-up. The independent Student's t test and chi-square test were applied to compare the differences between groups.

RESULTS

A total of 25 patients from TTL group were matched to 25 patients in PSVPH group for age, sex, body mass index (BMI), defect side, spondylolisthesis meyerding, and follow-up duration. The intervertebral space height (IH) of stabilized segment at postoperative 1 week and final follow-up in the TTL group was higher than those in the PSVPH group, respectively (P = 0.030; P = 0.013). The ROM of stabilized segment at final follow-up in the TTL group was significantly lower than that in the PSVPH group (P < 0.001). The bony fusion rate at the final follow-up was 88.0% (22/25 cages) in the TTL group and 80.0% (20/25 cages) in the PSVPH group. The ODI score at final follow-up in the TTL group was significantly lower than that in the PSVPH group (P = 0.007).

CONCLUSION

Overall, our data suggest that the Isobar TTL system outcomes are comparable to those in the PSVPH, with a similar high bony fusion rate as PSVPH, especially its wider indications as a new surgery.

Main and contralateral side stages of lesion affected bone union in the conservative treatment of adolescent lumbar spondylolysis: a multivariable analysis of 217 patients and 298 lesions in a retrospective cohort study

BACKGROUND

Factors affecting bone union in the conservative treatment of adolescent lumbar spondylolysis remain controversial. We aimed to examine these factors along with advances in diagnostic imaging using multivariable analysis of a sufficient number of patients and lesions.

METHODS

In this retrospective study, high-school-aged patients or younger (n = 514) who were diagnosed with lumbar spondylolysis from 2014 to 2021 were investigated. We included patients with acute fractures who showed signal changes around the pedicle on magnetic resonance imaging and who completed conservative treatment. The following factors were investigated at the initial visit: age, sex, level of lesion, main side stage, presence and stage of contralateral side lesion, and presence of spina bifida occulta. The association of each factor with bone union was evaluated through a multivariable analysis.

RESULTS

Altogether, 298 lesions in 217 patients (174 boys and 43 girls; mean age: 14.3 years) were included in this study. Multivariable logistic regression analysis of all factors showed that the main side progressive stage was more likely associated with nonunion as compared to the pre-lysis (OR: 5.86; 95% confidence interval [CI]: 2.00-18.8; p = 0.0011) and early stages (OR: 3.77; 95% CI: 1.72-8.46; p = 0.0009). Regarding the contralateral side stage, the terminal stage was more likely to be associated with nonunion.

CONCLUSION

In the conservative treatment of lumbar spondylolysis, the factors affecting bone union were the main and contralateral side stages. Sex, age, level of lesion, or spina bifida occulta had no significant effects on bone union. The main, progressive, and contralateral side terminal stages were negative predictors of bone union. Trial registration This study was retrospectively registered.

Abnormal L5-S1 Facet Joint Orientation as a Harbinger of Degenerative Spondylolisthesis: A Case Report

Degenerative spondylolisthesis is a common cause of low back pain and resultant disability in the adult population. The causes of degenerative spondylolisthesis are not entirely understood, though a combination of anatomic and lifestyle factors likely contributes to the development of this pathology. Here, we report a case of a 38-year-old female presenting with low back pain and right lower extremity radiculopathy, found to have degenerative L5-S1 spondylolisthesis, which we postulate developed in part due to the sagittal orientation of her L5-S1 facet joints bilaterally.

Relationship between Isokinetic Trunk Muscle Strength and Return to Sports Competition after Conservative Therapy in Fresh Cases of Lumbar Spondylolysis: A Retrospective Observational Study

This study aimed to clarify the relationship between isokinetic trunk muscle strength and return to sporting activities in fresh cases of lumbar spondylolysis treated with conservative therapy. Patients included a total of ten men (age: 13.5 ± 1.7) who were instructed by their attending physicians to stop exercising and who met the eligibility criteria. Isokinetic trunk muscle strength was measured immediately after exercising for the first time (First) and one month (1M). Flexion and extension and maximum torque/body weight ratio were significantly lower First compared to 1M at all angular velocities (p < 0.05). Maximum torque generation time was significantly lower for First at 120°/s and 180°/s than at 1M (p < 0.05). Correlations with the number of days to return to sports competition were detected at 60°/s for maximum torque generation time (p < 0.05, r = 0.65). Following conservative treatment for lumbar spondylolysis, it was considered necessary to focus on trunk flexion and extension muscle strength and contraction speed of trunk flexors at the beginning of the exercise period. It was suggested that trunk extension muscle strength in the extension range might be one of the critical factors for returning to sports.