The Joe-Lin Operative Classification System for Pediatric Lumbosacral Spondylolysis and Spondylolisthesis.

OBJECTIVE: To propose and validate a novel and comprehensive classification of lumbosacral spondylolysis and spondylolisthesis in the pediatric population according to surgical managements. METHODS: Cases of pediatric lumbosacral (L5/S1 level) spondylolysis and spondylolisthesis were reviewed. Lumbar Japanese Orthopedics Association score, health-related quality of life, spondylolisthesis, lumbosacral disc degeneration, and dysplastic features were included for evaluation of outcomes after surgery. We also conducted a reliability study to assess the classification. RESULTS: A classification containing 4 types and a tentative treatment algorithm were proposed: type 1, direct pars repair without segmented fusion, for which the pedicle screw-U rod system is suitable; type 2, simple L5-S1 fusion; type 3, simple L4-S1 fusion; and type 4, simple L5-S2 fusion. All types of spondylolisthesis were suggested to achieve complete reduction and decompression. A total of 162 patients were included and we also reviewed the outcomes of patients in each type. All patients achieved satisfied outcomes. The reliability study showed that the average interobserver agreement was 89.5% (range, 85.2%-92.6%), with κ value of 0.862 (range, 0.802-0.901). Intraobserver agreement ranged from 88.9% to 92.6%, with an average κ value of 0.868 (range, 0.835-0.901). CONCLUSIONS: In our study, we proposed and validated a novel comprehensive classification of pediatric lumbosacral spondylolysis and spondylolisthesis. The pedicle screw-U rod system provided more benefits in the treatment of simple lumbosacral spondylolysis, and fusion from L5 to S2 combined with S2 screw would also benefit patients with high-degree spondylolisthesis.

Current evaluation and management of spondylolysis and spondylolisthesis.

Spondylolysis occurs with a prevalence of 4% to 6% in the general population. Although the etiology of this lesion is still unclear, it has been shown to have both hereditary and acquired risk factors, with an increased prevalence in men and athletes participating in certain high-risk sports. Spondylolisthesis occurs in a significant proportion of individuals with bilateral spondylolysis. Predicting risk factors for progression of the slip in spondylolisthesis has proven difficult. Multiple imaging techniques are helpful in the diagnosis of spondylolysis and spondylolisthesis, with recent research addressing the utility of magnetic resonance imaging in the diagnosis and management of pars lesions. The management guidelines have remained largely unchanged since early recommendations. Recently, the addition of a bone growth stimulator to the management of difficult cases has shown promise.

"Perfect health" versus "disease free": the impact of anchor point choice on the measurement of preferences and the calculation of disease-specific disutilities.

BACKGROUND: During preference testing, some investigators use "perfect health" as the upper anchor point of their measurement scale ("Q scale"), whereas others use "disease free" ("q scale"), which can confound the interpretation and comparison of study results. METHODS: We measured current health preferences among 74 patients with cervical spondylotic myelopathy (CSM) on both the Q and q scales using the visual analogue scale (VAS), standard gamble (SG), time tradeoff (TTO), and willingness to pay (WTP). RESULTS: There were significant differences in mean Q and q scale values for the VAS, SG, and WTP (for all, P < 0.011); there were no significant differences for mean TTO values (P = 0.592). CSM accounted for 63% to 82% of total disutility, whereas other comorbidities accounted for 28% to 37%. CONCLUSIONS: Preferences for CSM differ when measured on the Q and q scales. Caution should be used when comparing and interpreting health values measured on scales with different upper anchors.

Spondylolysis and spondylolisthesis in the pediatric and adolescent population.

This article is a review of spondylolysis and spondylolisthesis in younger age groups. Since Herbinaux first described the pathology (1782), many classifications and theories of etiopathogenesis have been proposed. The congenital and isthmic types, as classified by Wiltse, are the most frequent in younger age groups, but the postsurgical progressive forms (3-5%) have been described as increasing in frequency secondary to neoplastic surgery in children. The general incidence is 4-5% at the age of 6 years, and in 30-50% of cases these types do not progress to spondylolisthesis. Most cases are asymptomatic (80%). Standard radiographic examinations (A-P, L, Oblique) are helpful in diagnosis and can suggest what the prognosis will be in terms of the evolution, and also what treatment is indicated (degree of slippage, slip angle, lumbar and lumbosacral index, SPTI). A bone scan (PBS and SPECT) is useful in the early stages of spondylolysis (pre-spondylosis). Although the CT scan is the most accurate examination, MRI is becoming important for diagnosis because of the frequency with which it is used as a primary investigation method. Depending on patient age, progression, degree of slippage, and symptoms, different therapeutic approaches have been proposed and are described in this paper.

Does the iliolumbar ligament prevent anterior displacement of the fifth lumbar vertebra with defects of the pars?

We studied 23 patients with spondylolysis of the fifth lumbar vertebra (L5) and 20 with spondylolytic spondylolisthesis at this level. All were more than 40 years of age. The transverse processes at L5 were significantly wider in the former group than in the latter. We also dissected 56 cadavers to study the morphological relationship between the transverse process of L5 and the iliolumbar ligament, and found that the wider transverse process is associated with increased width of the posterior band of the iliolumbar ligament. If a patient with pars defects has wide transverse processes at L5, the lumbosacral junction may be stabilised by wide posterior bands of the iliolumbar ligament and the fifth lumbar vertebra by the ligament, preventing anterior displacement.

Orientation of lumbar pars defects: implications for radiological detection and surgical management.

Lateral oblique radiographs are considered important for the identification of spondylolytic lesions, but these projections will give a clear view only when the radiological beam is in the plane of the defect. We studied the variation in orientation of spondylolytic lesions on CT scans of 34 patients with 69 defects. There was a wide variation of angle: only 32% of defects were orientated within 15 degrees of the 45 degrees lateral oblique plane. Lateral oblique radiographs should not be considered as the definitive investigation for spondylolysis. We suggest that CT scans with reverse gantry angle are now more appropriate than oblique radiography for the assessment of spondylolysis. Variation in the angle of the defect may also need consideration when direct repair is being planned.

Treatment of spondylolysis and spondylolisthesis in children and adolescents.

The treatment of spondylolysis and spondylolisthesis in children depends on the severity of clinical symptoms, pathologic anatomy, and prognosis. Simple spondylolysis can be cured by immobilization alone in selected cases, or by surgery when it remains symptomatic and resistant to nonoperative treatment. The majority of cases are asymptomatic and require no treatment. Spondylolisthesis is classified into 2 types based on the magnitude of the lumbosacral angle: spondylolisthesis with a horizontal sacrum (lumbosacral angle > or = 100 degrees), which seldom requires surgical treatment, usually responds to orthotic management, and generally shows little progression; spondylolisthesis with a vertical sacrum (lumbosacral angle < 100 degrees) which is always progressive, can produce neurologic impairment and cosmetic and functional disability, and requires surgical treatment. In 17 cases the author has reduced the latter deformity by gradual traction in hyperextension followed by cast immobilization, then stabilized the reduction by posterolateral fusion performed through the cast without instrumentation and without opening the spinal canal. When the lumbosacral angle is not improved to 100 degrees or more by hyperextension and traction, an anterior console interbody fusion is added before the posterolateral fusion.

Lumbar spondylolysis in children and adolescents.

We investigated 185 adolescents under the age of 19 years with spondylolysis. All but five were active in sport. The pars defect was classified into early, progressive and terminal stages. Of the 346 pars defects in 185 patients, 39.6% were early, 29.5% progressive and 30.9% in the terminal stages. Conservative management produced healing in 73.0% of the early, 38.5% of the progressive and none of the terminal defects. These results suggest that spondylolysis is caused by repetitive microtrauma during growth and can be successfully treated conservatively if treatment is started in the early stage. There was elongation of the pars interarticularis as the pars defect progressed, and this is likely to be a consequence of the defect rather than a contributing cause.

Classification of spondylolisis and spondylolisthesis.

A working classification of spondylolysis and spondylolisthesis which encompasses the salient features of the disorder, has been presented. It is based on both etiological and anatomical factors.