Spondylolytic spondylolisthesis: various imaging features and natural courses

Pars Interarticularis and Pedicle Stress Injuries in Young Athletes With Low Back Pain: A Retrospective Cohort Study of 902 Patients Evaluated With Magnetic Resonance Imaging

BACKGROUND

Previous studies have reported that spondylolysis occurs predominantly at the L5 and L4 levels, with defects at higher levels occurring in <5% of cases. However, computed tomography and radiography were the primary imaging modalities in these studies. Current evidence regarding diagnostic imaging for pediatric lumbar spondylolysis suggests that magnetic resonance imaging (MRI) is as accurate as computed tomography in detecting early stress reactions of the pars interarticularis or pedicles without fractures while avoiding radiation exposure. The early detection of spondylolysis results in a higher likelihood of bony union and a decreased likelihood of spondylolisthesis.

HYPOTHESIS

The increased use of MRI may reveal a larger proportion of spondylolysis in patients who experience an injury at a higher spinal level than previously reported.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

The medical records of 902 pediatric and adolescent athletes (364 female, 538 male) diagnosed with symptomatic pars interarticularis and pedicle stress injuries at 2 academic medical centers between 2016 and 2021 were retrospectively reviewed. All patients had MRI scans taken at the time of diagnosis. Only patients with pars/pedicle edema on MRI were included. Data regarding spondylolysis stage, spinal level of injury, unilateral versus bilateral injury, sport participation, and MRI protocol over the 5-year study period were analyzed.

RESULTS

Male patients presented at older ages than female patients (P < .001). Soccer was the most common sport at symptom onset and the second most common single-sport activity among those who specialized (participating in 1 sport year-round at the exclusion of others), behind gymnastics. The mean symptom duration was 4.0 months. Although most patients (83.5%) had exclusively lower lumbar stress injuries, 9.1% of injuries occurred at or above the L3 level. Over half of the patients had active single-level pars/pedicle fractures on MRI, with a mean symptom duration before presentation in this subgroup of 4.0 months. Even when pars/pedicle stress reactions were excluded from analysis, 7.1% of patients were injured at or above the L3 level.

CONCLUSION

Among male and female athletes aged 8 to 21 years presenting with symptomatic pars interarticularis and pedicle stress injuries evaluated by MRI at the time of initial diagnosis, there was a higher incidence of upper lumbar stress injuries than previously reported.

A radiological parametric comparison of low-grade lytic spondylolisthesis to degenerative spondylolisthesis - A retrospective approach to establish its dysplastic origin

Objectives

This study aims to compare low-grade lytic spondylolisthesis (LS) and degenerative spondylolisthesis (DS) radiologically. In addition, it seeks to identify underlying similarities between LS and DS.

Methods

This study included patients with low-grade single-level spondylolisthesis at L4-L5 or L5-S1. They were categorized into LS and DS. Radiological features, including pedicle height, width, transverse, and sagittal angle, as well as anterior vertebral heights (AVH) and posterior vertebral heights (PVH), were measured using T1-weighted magnetic resonance imaging.

Results

The study involved 88 patients: 46 in the DS group and 42 in the LS group. In the LS group, the AVH was significantly higher than the posterior height at L4 and L5 (L4 PVH/AVH ratio 0.93 in LS vs. 0.96 in DS; L5 PVH/AVH ratio 0.84 in LS vs. 0.92 in DS), and pedicles were more medially oriented (L4: 19.62° in LS vs. 17.7° in DS; L5: 28.92° in LS vs. 26.47° in DS). In addition, at L5, the pedicle height (10.67 mm in LS vs. 11.48 mm in DS) and width (13.56 mm in LS vs. 14.37 mm in DS) were smaller compared to the DS group.

Conclusions

Low-grade LS shows distinct radiological vertebral and pedicle anatomy compared to DS. Short and thin pedicles and wedge-shaped vertebrae in LS resemble DS, indicating its dysplastic origin.

Utility of ultrasonography in the diagnosis of lumbar spondylolysis in adolescent patients

BACKGROUND

This study aims to investigate the utility of the Doppler effect on ultrasonography for the diagnosis of very early- and early-stage lumbar spondylolysis in adolescent patients.

METHODS

In total, 76 adolescent patients with acute and subacute low back pain were prospectively enrolled, with 46 having lumbar spondylolysis and the remaining 30 having low back pain without spondylolysis. MRI and/or computed tomograms scans revealed very early- and early-stage lumbar spondylolysis. Furthermore, positive Doppler findings in ultrasonography around the area from the facet joint to the laminae were investigated.

RESULTS

There were no significant differences in age (p > 0.99) and body mass index (p = 0.11) between cases with and without spondylolysis. Very early- and early-stage spondylolysis were observed in 27.6% and 72.4% of patients, respectively. Positive power Doppler was 91.3% and 33.3% in cases with and without spondylolysis, respectively, which was significantly higher in spondylolysis (p < 0.001). The sensitivity and specificity of this positive power Doppler were 91.4% and 66.7%, respectively. Furthermore, the rate of positive power Doppler was significantly higher in early-stage spondylolysis (p = 0.02), with 75.0% and 97.6% sensitivity in very early- and early-stage spondylolysis, respectively.

CONCLUSIONS

A positive Doppler effect on ultrasonography is effective for screening very early- and early-stage spondylolysis in adolescent patients in an outpatient clinic.

Diagnostic Performance of the Darth Vader Sign for the Diagnosis of Lumbar Spondylolysis in Routinely Acquired Abdominal CT

Spondylolysis is underdiagnosed and often missed in non-musculoskeletal abdominal CT imaging. Our aim was to assess the inter-reader agreement and diagnostic performance of a novel "Darth Vader sign" for the detection of spondylolysis in routine axial images. We performed a retrospective search in the institutional report archives through keyword strings for lumbar spondylolysis and spondylolisthesis. Abdominal CTs from 53 spondylolysis cases (41% female) and from controls (n = 6) without spine abnormalities were identified. A total of 139 single axial slices covering the lumbar spine (86 normal images, 40 with spondylolysis, 13 with degenerative spondylolisthesis without spondylolysis) were exported. Two radiology residents rated all images for the presence or absence of the "Darth Vader sign". The diagnostic accuracy for both readers, as well as the inter-reader agreement, was calculated. The "Darth Vader sign" showed an inter-reader agreement of 0.77. Using the "Darth Vader sign", spondylolysis was detected with a sensitivity and specificity of 65.0-88.2% and 96.2-99.0%, respectively. The "Darth Vader sign" shows excellent diagnostic performance at a substantial inter-reader agreement for the detection of spondylolysis. Using the "Darth Vader sign" in the CT reading routine may be an easy yet effective tool to improve the detection rate of spondylolysis in non-musculoskeletal cases and hence improve patient care.

Curve Characteristics and Response of Sciatic and Olisthesis Scoliosis Following L5/S1 Transforaminal Lumbar Interbody Fusion in Adolescent Lumbar Spondylolisthesis

BACKGROUND

Lumbosacral spondylolisthesis-induced scoliosis is a rare clinical entity. Sagittal reconstruction and the coronal curve evolution after surgery for spondylolisthesis have not been investigated in depth.

OBJECTIVE

To compare the curve characteristics between sciatic scoliosis and olisthetic scoliosis and to further investigate the effects of lumbosacral transforaminal lumbar interbody fusion (TLIF) on scoliosis evolution.

METHODS

Adolescents with sciatic scoliosis group (SS group) or olisthetic scoliosis group (OS group) who underwent L5/S1 TLIF from 2010 to 2017 and were followed up for at least 2 yr were retrospectively reviewed. Radiographic parameters and patient-reported outcomes were evaluated.

RESULTS

There were 20 patients in the SS group (M/F: 8/12; age: 15.6 ± 2.2 yr) and 16 in the OS group (M/F: 6/10; age: 16.8 ± 2.5 yr). Both groups had similar preoperative Cobb angles, but more patients with coronal imbalance were observed in the SS group. Moreover, the OS group showed significantly larger L5 tilt and rotation. After surgery, the slip reduction rate of the SS group and OS group were 76.1% ± 12.4% and 79.4% ± 9.6%, respectively. Scoliosis resolution was observed in all patients in the SS group but only in 9 patients (56.2%) in the OS group. Patients with failed scoliosis resolution in the OS group were older and had a larger Cobb angle and L5 rotation compared with those with successful scoliosis resolution.

CONCLUSION

Lumbosacral TLIF can achieve satisfactory slip reduction and scoliosis resolution. Sciatic scoliosis often presents with coronal imbalance but also a preferable curve prognosis. A large Cobb angle and L5 rotation may hinder the resolution of olisthetic scoliosis.

Minimally Invasive Reconstruction of Vertebral Arch in Spondylolisthesis in Children and Adolescents

The aim of the study was to assess the effectiveness of the minimally invasive technique used to reconstruct the vertebral arch with a pedicle screw hook system in grade I isthmic spondylolisthesis in comparison with the traditional technique of segment stabilization with interbody fusion.

The Incidence of Pars Interarticularis Defects in Athletes

STUDY DESIGN

Literature review.

OBJECTIVE

To conduct a literature review of studies reporting the incidence of pars interarticularis defects in athletes of specific sports, in order to allow more targeted prevention and treatment strategies to be implemented for the groups at highest risk.

METHODS

Electronic searches were performed using PubMed, Ovid Medline, EMBASE, Google Scholar, Cochrane Database of Systematic Reviews, and Cochrane Database of Controlled Trials from their dates of inception to September 2017, with the following keywords: "spondylolysis," "sports," "low back pain," and "pars defects."

RESULTS

A total of 509 total articles were retrieved, of which 114 were used in the final review. The incidence of pars interarticularis defects was found to be highest in diving (35.38%), cricket (31.97%), baseball/softball (26.91%), rugby (22.22%), weightlifting (19.49%), sailing (17.18%), table tennis (15.63%), and wrestling (14.74%). Only 5 studies reported the management instituted for their participants, and these were all case reports. Of 74 players with spondylolysis in these studies, 70 (94.59%) underwent conservative treatment and 4 (5.41%) underwent surgical treatment. 61 (82.43%) returned to their previous level of play, 6 (8.11%) retired, and the disposition of the final 7 was not reported.

CONCLUSION

The current medical literature provides good evidence that the incidence of pars interarticularis defects is higher in the athletic population, with the highest incidence in diving. There remains no gold standard protocol for the management of pars interarticularis defects. Further research is required to compare conservative therapy to surgical therapy and to compare the various surgical techniques to each other.

Sagittal reconstruction of lumbosacral contiguous double-level spondylolytic spondylolisthesis: a comparison of double-level and single-level transforaminal lumbar interbody fusion

Background

Contiguous double-level lumbar spondylolytic spondylolisthesis is an extremely rare condition. There is a paucity of data of lumbosacral deformity and sagittal spino-pelvic malalignment among these patients. Moreover, the effect of transforaminal lumbar interbody fusion (TLIF) on sagittal realignment still remains largely unknown. The aim of the study is to investigate the reconstruction of sagittal alignment and the improvement of clinical outcomes after posterior instrumented double-level or single-level TLIF.

Methods

From January 2010 to September 2018, the records of patients with contiguous L4/5 and L5/S1 double-level spondylolytic spondylolisthesis were retrospectively reviewed. Patients who had undergone double-level or single-level TLIF and a minimum of 2 years’ follow-up were included. The slippage parameters and spino-pelvic parameters were measured preoperatively, postoperatively, and at the latest follow-up.

Results

A total of 58 patients (21 males and 37 females, mean age of 57.1 ± 6.9 years) were enrolled. Thirty-eight patients were treated with double-level TLIF and the remaining 20 with single-level TLIF (L4/5 in 14; L5/S1 in 6). After surgery, the spondylolisthesis was significantly reduced at both L4/5 and L5/S1 level (all P < 0.001). There was a significant reduction in pelvic tilt (P < 0.001) and a significant increase in sacral slope (P < 0.001). Significant increase in L4–S1 height (P < 0.001) and L4–S1 lordosis (P = 0.012) and decrease in L5 slope (P = 0.004) and L5 incidence (P = 0.001) were also observed. Compared to single-level TLIF, double-level TLIF increased L4–S1 height (P < 0.001) and L4–S1 lordosis (P < 0.001) and reduced L4-SVA (P = 0.007) and L5 incidence (P = 0.013) more obviously, and the sagittal balance was better corrected in double-level TLIF group (P = 0.006). Double-level TLIF group showed larger increase in VAS scores for low back pain. The incidence of implant-related complications was lower in the double-level group.

Conclusion

Posterior short-segment instrumented TLIF can bring favorable radiographic and clinical outcomes in patients with lumbosacral contiguous double-level spondylolytic spondylolisthesis. Double-level TLIF is more efficient to improve L4–S1 height, regional lumbar lordosis, and global sagittal balance.

Facet Joints of the Spine: Structure–Function Relationships, Problems and Treatments, and the Potential for Regeneration

The zygapophysial joint, a diarthrodial joint commonly referred to as the facet joint, plays a pivotal role in back pain, a condition that has been a leading cause of global disability since 1990. Along with the intervertebral disc, the facet joint supports spinal motion and aids in spinal stability. Highly susceptible to early development of osteoarthritis, the facet is responsible for a significant amount of pain in the low-back, mid-back, and neck regions. Current noninvasive treatments cannot offer long-term pain relief, while invasive treatments can relieve pain but fail to preserve joint functionality. This review presents an overview of the facet in terms of its anatomy, functional properties, problems, and current management strategies. Furthermore, this review introduces the potential for regeneration of the facet and particular engineering strategies that could be employed as a long-term treatment.

The effect of transforaminal epidural steroid injections in patients with spondylolisthesis

BACKGROUND

Transforaminal epidural steroid injection (TFE) is a widely accepted non-surgical treatment for pain in patients with spondylolisthesis. However, the effectiveness of TFE has not been compared in patients with degenerative (DS) and isthmic spondylolisthesis (IS).

OBJECTIVE

To compare the effectiveness of bilateral TFEs in DS and IS.

METHODS

Patients who underwent bilateral TFEs for spondylolisthesis at University of California San Francisco Orthopaedic Institute from 2009 to 2014 were evaluated retrospectively.

RESULTS

DS patients (120 female, 51 male) were significantly older and had higher comorbidity than those with IS (18 female, 14 male). They had better pain relief after TFE than patients with IS (72.11 ± 27.46% vs 54.39 ± 34.31%; p = 0.009). The number of TFEs, the mean duration of pain relief after TFE, follow-up periods, translation and facet joint widening were similar in DS and IS groups (p > 0.05). DS group had higher successful treatment rate (66.1% vs 46.9%, p = 0.009) and longer duration of pain relief (181.29 ± 241.37 vs 140.07 ± 183.62 days, p = 0.065) compared to IS group.

CONCLUSIONS

Bilateral TFEs at the level of spondylolisthesis effectively decreased pain in patients. TFEs provided better pain relief for longer duration in patients with DS than for those with IS.

Characterization of radiographic features of consecutive lumbar spondylolisthesis

Radiographic features of consecutive lumbar spondylolisthesis were retrospectively analyzed in a total of 17 patients treated for this condition at the Third Hospital of Hebei Medical University from June 2005 to March 2012.To investigate the radiographic features, pelvic compensatory mechanisms, and possible underlying etiologies of consecutive lumbar spondylolisthesis.To the best of our knowledge, there is no previous report concerning the characteristics of consecutive lumbar spondylolisthesis.The Taillard index and the lumbar lordosis (LL), pelvic incidence (PI), sacrum slope (SS), and pelvic tilt (PT) were determined on lateral X-ray images, and the angular displacement was analyzed on flexion-extension X-ray images. Correlation between LL and various pelvic parameters and correlation between Taillard index and angular displacement were assessed by Pearson correlation analysis.A total of 20 cases of isthmic spondylolisthesis and 14 of degenerative spondylolisthesis were retrospectively studied in 17 patients. The Taillard index and the angular displacement in the lower vertebrae were both larger than those in the upper vertebrae. Statistical analysis revealed that LL was correlated with PI and PT, whereas PI was correlated with PT and SS. However, no correlation was identified between Taillard index and angular displacement.In consecutive lumbar spondylolisthesis, the degree of vertebral slip and the angular displacement of the lower vertebrae were both greater than those of the upper vertebrae, indicating that the compensatory mechanism of the pelvis plays an important role in maintaining sagittal balance.

Atypical, unusual, and misleading imaging presentations of spondylolysis

Although lumbar spondylolysis is a widely known and easily recognizable condition in its typical presentation, there are some less well-known forms that may occasionally be challenging and/or demand special attention on imaging. Examples include: acute and/or incomplete lesions; unilateral defects; lesions at unusual levels (cervical, upper lumbar, and multi-level spondylolyses); iatrogenic lesions; non-isthmic spondylolysis; and spondylolysis related to underlying diseases. In addition to their atypical, uncommon or confusing imaging presentations, these forms of spondylolysis are far rarer than the classic type and have been described, to a great extent, in the surgical literature, thus reducing the awareness of radiologists about them and raising the potential for misdiagnosis and inadequate treatment. In this review the authors address these special manifestations of spondylolysis, stressing the more important features to be considered in the differential diagnosis and the impact of a precise diagnosis of spondylolysis on the patient's care.