Spondylolisthesis caused by extreme pedicle elongation in osteogenesis imperfecta

Postoperative screw pullout of severe spondylolisthesis in osteogenesis imperfecta: a case report with 3-year follow-up

Introduction and importance

Osteogenesis imperfecta (OI) is a rare skeletal disorder characterized by bone fragility and deformities in both paediatric and adult populations. The occurrence of severe spondylolisthesis in OI patients is even more infrequent. However, there is no consensus regarding the optimal treatment approach for OI patients afflicted with severe spondylolisthesis. The selection of surgical procedures and the effective management of postoperative complications present significant challenges in this context.

Case presentation

A 30-year-old male patient diagnosed with OI type IV (Sillence classification) underwent the lumbar laminectomy and postero-lateral fusion due to severe spondylolisthesis (grade Ⅲ). Following the surgery, the patient experienced postoperative screw pullout while on bedrest. However, aside from experiencing back pain, there were no neurological symptoms present. To address this issue, the patient received salvage treatment in the form of cast immobilization combined with bisphosphonates. At the 3-year follow-up, the patient exhibited absence of sciatic nerve pain and reported mild numbness in the lower extremities. Moreover, the patient demonstrated the ability to ambulate a distance exceeding 1500 m. Nevertheless, the persistence of sexual dysfunction was observed.

Clinical discussion

This study presented the initial instance of surgical complications observed in patients with severe spondylolisthesis and OI. This highlights the importance to exercise meticulous caution and thoroughness when assessing surgical interventions.

Conclusion

In cases where the fixation fails to offer adequate biomechanical stability, the administration of bisphosphonates and robust immobilization remains crucial, even in the presence of complications.

Pain Phenotypes in Rare Musculoskeletal and Neuromuscular Diseases

For patients diagnosed with a rare musculoskeletal or neuromuscular disease, pain may transition from acute to chronic; the latter yielding additional challenges for both patients and care providers. We assessed the present understanding of pain across a set of ten rare, noninfectious, noncancerous disorders; Osteogenesis Imperfecta, Ehlers-Danlos Syndrome, Achondroplasia, Fibrodysplasia Ossificans Progressiva, Fibrous Dysplasia/McCune-Albright Syndrome, Complex Regional Pain Syndrome, Duchenne Muscular Dystrophy, Infantile- and Late-Onset Pompe disease, Charcot-Marie-Tooth Disease, and Amyotrophic Lateral Sclerosis. Through the integration of natural history, cross-sectional, retrospective, clinical trials, & case studies we described pathologic and genetic factors, pain sources, phenotypes, and lastly, existing therapeutic approaches. We highlight that while rare diseases possess distinct core pathologic features, there are a number of shared pain phenotypes and mechanisms that may be prospectively examined and therapeutically targeted in a parallel manner. Finally, we describe clinical and research approaches that may facilitate more accurate diagnosis, monitoring, and treatment of pain as well as elucidation of the evolving nature of pain phenotypes in rare musculoskeletal or neuromuscular illnesses.

Phenotypic characterization of Slc26a2 mutant mice reveals a multifactorial etiology of spondylolysis

Confusion persists over pathogenesis of spondylolysis. To confirm pathogenicity of the previously identified causative mutation of spondylolysis and investigate the genetic etiology, we generate a new mouse line harboring D673V mutation in the Slc26a2 gene. D673V mutation induces delayed endochondral ossification characterized by transiently reduced chondrocyte proliferation in mice at the early postnatal stage. Adult D673V homozygotes exhibit dysplastic isthmus and reduced bone volume of the dorsal vertebra resembling the detached vertebral bony structure when spondylolysis occurs, including the postzygopophysis, vertebral arch, and spinous process, which causes biomechanical alterations around the isthmic region of L4-5 vertebrae indicated by finite element analysis. Consistently, partial ablation of Slc26a2 in vertebral skeletal cells using Col1a1-Cre; Slc26a2 ^fl/fl mouse line recapitulates a similar but worsened vertebral phenotype featured by lamellar isthmus. In addition, when reaching late adulthood, D673V homozygotes develop an evident bone-loss phenotype and show impaired osteogenesis. These findings support a multifactorial etiology, involving congenitally predisposed isthmic conditions, altered biomechanics, and age-dependent bone loss, which leads to SLC26A2-related spondylolysis.

Complex spine deformities in young patients with severe osteogenesis imperfecta: current concepts review

The severity of osteogenesis imperfecta (OI), the associated reduced quality and quantity of collagen type I, the degree of bone fragility, ligamentous laxity, vertebral fractures and multilevel vertebral deformities all impair the mechanical integrity of the whole spinal architecture and relate to the high prevalence of progressive kyphoscoliotic deformities during growth. Bisphosphonate therapy may at best slow down curve progression but does not seem to lower the prevalence of deformities or the incidence of surgery. Brace treatment is problematic due to pre-existing chest wall deformities, stiffness of the curve and the brittleness of the ribs which limit transfer of corrective forces from the brace shell to the spine. Progressive curves entail loss of balance, chest deformities, pain and compromise of pulmonary function and eventually require surgical stabilization, usually around puberty. Severe vertebral deformities including deformed, small pedicles, highly brittle bones and chest deformities, short deformed trunks and associated issues like C-spine and cranial base abnormalities (basilar impressions, cervical kyphosis) as well as deformed lower and upper extremities are posing multiple peri- and intraoperative challenges. Hence, an early multidisciplinary approach (anaesthetist, pulmonologist, paediatric orthopaedic spine surgeon) is mandatory. This paper was written under the guidance of the Spine Study Group of the European Paediatric Orthopaedic Society. It highlights the most pertinent information given in the current literature and various practical aspects on surgical care of spine deformities in young OI patients based on the personal experience of the contributing authors.

The genetic implication of scoliosis in osteogenesis imperfecta: a review

Osteogenesis imperfecta (OI) is a kind of heritable connective tissue disorder, including blue sclerae, hearing loss, skeletal dysplasia causing bone fragility and deformities. It is typically caused by collagen related gene mutations, which could lead to bone formation abnormalities. Scoliosis is one of the most common and severe spinal phenotype which has been reported in approximately 26-74.5% of all OI patients. Recent breakthroughs have suggested that OI can be divided into more than 16 types based on genetic mutations with different degrees of scoliosis. In this review, we summarize the etiology of scoliosis in OI, especially the genetic studies of different types. We aim to provide a systematic review of the genetic etiology and clinical suggestions of scoliosis in OI.

Association between spondylolisthesis and L5 fracture in patients with Osteogenesis Imperfecta

PURPOSE

To investigate if an association between spondylolisthesis and L5 fracture occurs in patients affected by Osteogenesis Imperfecta (O.I.).

METHODS

Anteroposterior and lateral radiograms were performed on the sample (38 O.I. patients, of whom 19 presenting listhesis); on imaging studies spondylolisthesis was quantified according to the Meyerding classification. Genant's semiquantitative classification was applied on lateral view to evaluate the L5 fractures; skeleton spinal morphometry (MXA) was carried out on the same images to collect quantitative data comparable and superimposable to Genant's classification. The gathered information were analyzed through statistical tests (O.R., χ 2 test, Fisher's test, Pearson's correlation coefficient).

RESULTS

The prevalence of L5 fractures is 73.7 % in O.I. patients with spondylolisthesis and their risk of experiencing such a fracture is twice than O.I. patients without listhesis (OR 2.04). Pearson's χ 2 test demonstrates an association between L5 spondylolisthesis and L5 fracture, especially with moderate, posterior fractures (p = 0.017) and primarily in patients affected by type IV O.I.

CONCLUSIONS

Spondylolisthesis represents a risk factor for the development of more severe and biconcave/posterior type fractures of L5 in patients suffering from O.I., especially in type IV. This fits the hypothesis that the anterior sliding of the soma of L5 alters the dynamics of action of the load forces, localizing them on the central and posterior heights that become the focus of the stress due to movement of flexion-extension and twisting of the spine. As a result, there is greater probability of developing an important subsidence of the central and posterior walls of the soma.

Orthopaedic Considerations for the Adult With Osteogenesis Imperfecta

Osteogenesis imperfecta is a heritable group of collagen-related disorders that affects up to 50,000 people in the United States. Although the disease is most symptomatic in childhood, adults with osteogenesis imperfecta also are affected by the sequelae of the disease. Orthopaedic manifestations include posttraumatic and accelerated degenerative joint disease, kyphoscoliosis, and spondylolisthesis. Other manifestations of abnormal collagen include brittle dentition, hearing loss, cardiac valve abnormalities, and basilar invagination. In general, nonsurgical treatment is preferred for management of acute fractures. High rates of malunion, nonunion, and subsequent deformity have been reported with both closed and open treatment. When surgery is necessary, surgeons should opt for load-sharing intramedullary devices that span the entire length of the bone; locking plates and excessively rigid fixation generally should be avoided. Arthroplasty may be considered for active patients, but the procedure frequently is associated with complications in this patient population. Underlying deformities, such as malunion, bowing, rotational malalignment, coxa vara, and acetabular protrusio, pose specific surgical challenges and underscore the importance of preoperative planning.

Craniospinal abnormalities and neurologic complications of osteogenesis imperfecta: imaging overview

Osteogenesis imperfecta is a rare genetic disorder that leads to progressive skeletal deformities due to deficits in type I collagen, the main pathophysiologic effect of the disease. In addition, it may lead to a wide range of associated neurologic abnormalities: The central nervous system is usually involved because of softening of bone at the base of the skull, with resultant upward migration of the upper cervical spine and odontoid process into the skull base. Upward migration of the spine may cause compression of the brainstem, mechanical impingement of the spinal canal with restriction of cerebrospinal fluid circulation, and impingement of the cranial nerves. Osteogenesis imperfecta also may directly involve neurovascular structures, leading to cavernous fistulas of the carotid artery, dissection of the cervical arteries, and cerebral aneurysms. The brain parenchyma is frequently affected by the disease, with manifestations including cerebral atrophy, communicating hydrocephalus, and cerebellar hypoplasia. The imaging features of the disorder vary as widely as its clinical manifestations, depending on the severity of disease. Severe forms accompanied by debilitating skeletal fractures and progressive neurologic impairments may lead to perinatal death, whereas milder asymptomatic forms might cause only a modest reduction in life span. The most important advance in medical therapy for osteogenesis imperfecta has been the introduction of bisphosphonate therapy to slow the resorption of bone in patients with moderate to severe forms of the disease (ie, type III or IV). In some patients, neurosurgery may be necessary to correct the effects of severe basilar invagination by the odontoid process.

Radiographic features of osteogenesis imperfecta

Background

Osteogenesis imperfecta (OI), commonly called “brittle bone disease”, is a genetic disorder characterised by increased bone fragility and decreased bone density due to quantitative and/or qualitative abnormalities of type I collagen. Different types of OI exist, from mild to severe; they may lead to death, multiple bone fractures, skeletal deformity and short stature.

Methods

Severe cases are usually diagnosed before birth and may incite the parents to choose therapeutic abortion, whereas milder cases are much more difficult to diagnose and may be sometimes confused with non-accidental injury (NAI) (“child abuse”) in young children. Whatever the degree of severity, conventional radiography still remains the mainstay in diagnosing OI.

Results

The prognosis of this disorder has changed in the last few years thanks to biphosphonate therapy.

Conclusion

The aim of this pictorial review is to illustrate the radiographic manifestations of OI, including in children receiving biphosphonates, and to outline specific patterns that help differentiate OI from NAI when necessary.

Key Points

• The main radiographic features of OI are osteopenia, bone fractures and bone deformities.

• Some radiographic features depend on the type of OI or may be encountered with biphosphonates.

The incidence of spondylolysis and spondylolisthesis in children with osteogenesis imperfecta

BACKGROUND

Spondylolysis and spondylolisthesis are common abnormalities of the lumbar spine. The incidence of these diagnoses is recognized in the healthy population. However, their incidence in osteogenesis imperfecta (OI) patients is less well defined.

METHODS

This is a retrospective radiographic review of patients treated in the OI clinic from a single institution. Lateral radiographs were reviewed on all available patients to assess the incidence of spondylolysis and spondylolisthesis in this patient population. The morphology of the pedicle and pars interarticularis was also evaluated to identify any abnormalities or dysplasia of these structures.

RESULTS

One hundred ten of the 139 patients treated in the OI clinic met the inclusion criteria for this study. Of these patients, 79% (87 of 110) were ambulatory. The overall incidence of spondylolysis in this pediatric OI population was found to be 8.2% (9 of 110) at an average age of 7.5 years. The incidence of spondylolisthesis was 10.9% (12 of 110) at an average age of 6.5 years with 75% (3 of 12) being isthmic type and 25% (3 of 12) dysplastic. The combined incidence of spondylolysis and spondylolisthesis was 19.2%. Incidentally, the pedicle length was noted to be elongated in 40.0% (44 of 110) of this OI population.

CONCLUSIONS

This study found that the incidence of spondylolysis in a group of children with OI was much higher than in the normal pediatric population, which has been reported to be 2.6% to 4.0%. This incidence was also found to be higher than previously reported incidence of spondylolysis in OI patients (5.3%). The incidence of spondylolisthesis was also found to be much higher than that of the normal pediatric population (4.2%). It is important to recognize this higher incidence of these abnormalities and to anticipate future associated symptoms and potential worsening listhesis that can clinically affect the lifestyles of these children and potentially require surgical treatment. The clinical significance of these findings will necessitate long-term follow-up.

Prevalence of vertebral pars defects (spondylolysis) in a population with osteogenesis imperfecta

STUDY DESIGN

We performed a retrospective study of spinal roentgenograms of a large cohort of patients suffering from osteogenesis imperfecta.

OBJECTIVE

To determine the prevalence of vertebral pars defects (spondylolysis) in patients with osteogenesis imperfecta.

SUMMARY OF BACKGROUND DATA

Patients suffering from osteogenesis imperfecta are known to be prone to pathologic fractures. Pathologic fractures due to microtraumas, repetitive activities, and posture acting together on a congenitally weakened pars interarticularis may lead to vertebral pars defects. The prevalence of vertebral pars defects in patients with osteogenesis imperfecta has never been studied before to our knowledge.

METHODS

We performed a retrospective study of posterior-anterior and lateral, standing, roentgenograms of the spine of patients with osteogenesis imperfecta for the occurrence of vertebral pars interarticularis defects.

RESULTS

The patients (5.3%) in our series showed vertebral pars defects, this is not significantly different from the prevalence of vertebral pars defects in the general population.

CONCLUSION

5.3% of the patients with osteogenesis imperfecta showed vertebral pars defects, this does not differ significantly from the occurrence in the general population.