Clinical utility of ultrasound to prospectively monitor distraction of magnetically controlled growing rods.

BACKGROUND CONTEXT: Growing rods are commonly used for surgical treatment of skeletally immature patients with scoliosis, but require repeated surgeries for distractions and are fraught with complications. As an alternative, the use of magnetically controlled growing rods (MCGR) allows for more frequent non-invasive distractions to mimic normal growth. However, more plain radiographs are needed to monitor increased distraction frequency, thereby increasing ionizing radiation exposure to the developing child. The use of ultrasound, which emits no radiation, has been found in a cross-sectional study to be reliable in measuring MCGR distractions. PURPOSE: The study aims to address the prospective clinical utility of ultrasound compared with plain radiographs for assessing MCGR distractions. STUDY DESIGN: This is a prospective study. PATIENT SAMPLE: The study includes patients with early-onset scoliosis undergoing distractions after MCGR implant. OUTCOME MEASURES: The distraction length on plain radiographs and ultrasound was measured. METHODS: This is a prospective study of patients treated with MCGR. Patients with both single- and dual-rod systems were included. Outpatient distractions were performed at monthly intervals, targeting 2 mm of distraction on each occasion. Assessment of distraction length was monitored by ultrasound at each visit; plain radiographs were taken every 6 months and were compared with ultrasound measurements. RESULTS: Nine patients (5 female, 4 male), with a mean of 29 distractions (standard deviation [SD] ±14.3), were recruited. The mean distracted length per 6 months was 5.7 mm (SD ±3.6 mm) on plain radiographs and 5.2 mm (SD ±3.9 mm) on ultrasound for the concave rod, and 6.1 mm (SD ±3.6 mm) on plain radiographs and 5.9 mm (SD ±3.8 mm) on ultrasound for the convex rod. Excellent inter- and intra-rater reliabilities were observed for radiographic and ultrasound measurements. An excellent correlation was noted between the two imaging modalities (r=0.93; p<.0001). CONCLUSIONS: This is the first prospective study to validate that ultrasound assessment of MCGR distraction lengths was highly comparable with that of plain radiographs. The present study has verified that ultrasound can be used to document length changes by distraction over time and that it had high clinical utility. Ultrasound can be a reliable alternative to plain radiographs, thereby avoiding radiation exposure and its potential detrimental sequelae in the developing child.

Disappearing bone disease of the humerus and the cervico-thoracic spine: a case report with 42-year follow-up.

BACKGROUND CONTEXT: Disappearing bone disease (DBD) is a rare idiopathic musculoskeletal disorder that is distinguished by bone resorption without bone formation, vascular or lymphatic vessel proliferation, and soft-tissue swelling. Long-term follow-up of a patient with DBD has rarely been reported in the literature. PURPOSE: The following is a case report of a female patient with DBD of the humerus and the spine who was followed for 42 years, documenting the progression of the disease and outcomes. STUDY DESIGN: Case report. METHODS: A review of the medical records since the time of initial hospital admission throughout follow-up was performed. RESULTS: A female patient was first seen at our institution at the age of 14. She later developed DBD of the humerus and the spine. The initial difficulty encountered was reaching the diagnosis, and later on with management of the patient as the disease progressed. The case was complicated by syrinx and arachnoid cyst formation, which caused neurologic changes leading to tetraplegia and shunt infection. The patient's inability to form a solid fusion mass led to repeated implant loosening and progressive deformity despite efforts made to stabilize both the humerus and the spine. The treatment modalities used were oral bisphosphonates, rhBMP, repeated surgeries, and instrumentation with adjunct bone graft and substitutes. At the age of 56 years, the patient died because of septicemia secondary to urinary tract infection from tetraplegia. CONCLUSIONS: To our knowledge, this is the first report documenting a 42-year follow-up of a patient with DBD of the humerus and the spine. Our report showed that DBD greatly affects the quality of life of the patient. Close follow-up, a multidisciplinary approach, and supportive care are stressed when managing patients with DBD.

Fundamentals of clinical outcomes assessment for spinal disorders: study designs, methodologies, and analyses.

Study Design A broad narrative review. Objective Management of spinal disorders is continuously evolving, with new technologies being constantly developed. Regardless, assessment of patient outcomes is key in understanding the safety and efficacy of various therapeutic interventions. As such, evidence-based spine care is an essential component to the armamentarium of the spine specialist in an effort to critically analyze the reported literature and execute studies in an effort to improve patient care and change clinical practice. The following article, part one of a two-part series, is meant to bring attention to the pros and cons of various study designs, their methodological issues, as well as statistical considerations. Methods An extensive review of the peer-reviewed literature was performed, irrespective of language of publication, addressing study designs and their methodologies as well as statistical concepts. Results Numerous articles and concepts addressing study designs and their methodological considerations as well as statistical analytical concepts have been reported. Their applications in the context of spine-related conditions and disorders were noted. Conclusion Understanding the fundamental principles of study designs and their methodological considerations as well as statistical analyses can further advance and improve future spine-related research.

Fundamentals of Clinical Outcomes Assessment for Spinal Disorders: Clinical Outcome Instruments and Applications.

Study Design A broad narrative review. Objectives Outcome assessment in spinal disorders is imperative to help monitor the safety and efficacy of the treatment in an effort to change the clinical practice and improve patient outcomes. The following article, part two of a two-part series, discusses the various outcome tools and instruments utilized to address spinal disorders and their management. Methods A thorough review of the peer-reviewed literature was performed, irrespective of language, addressing outcome research, instruments and tools, and applications. Results Numerous articles addressing the development and implementation of health-related quality-of-life, neck and low back pain, overall pain, spinal deformity, and other condition-specific outcome instruments have been reported. Their applications in the context of the clinical trial studies, the economic analyses, and overall evidence-based orthopedics have been noted. Additional issues regarding the problems and potential sources of bias utilizing outcomes scales and the concept of minimally clinically important difference were discussed. Conclusion Continuing research needs to assess the outcome instruments and tools used in the clinical outcome assessment for spinal disorders. Understanding the fundamental principles in spinal outcome assessment may also advance the field of "personalized spine care."