Pregnancy complicated by severe osteogenesis imperfecta poses a challenge for the anaesthetist: A case report.

Pregnant women with severe osteogenesis imperfecta (OI) are uncommon, and there are limited data regarding anaesthesia for caesarean section in these high-risk individuals. The presence of anatomical and physiological abnormalities can pose technical challenges for the anaesthetist. This report describes the successful implementation of epidural anaesthesia in a parturient with severe OI. To our knowledge, this is the first documented use of ultrasound-assisted neuraxial anaesthesia and wrist blood pressure monitoring in such patients undergoing caesarean section. Understanding the pathophysiological changes associated with OI is crucial for ensuring safe administration of anaesthesia to these women.

Influence of zoledronic acid and pamidronate on tooth eruption in children with osteogenesis imperfecta.

INTRODUCTION: Osteogenesis imperfecta (OI) is a congenital disease comprising a heterogeneous group of inherited connective tissue disorders. The main treatment in children is bisphosphonate therapy. Previous animal studies have shown that bisphosphonates delay tooth eruption. The aim of this study is to determine whether patients with OI treated with pamidronate and/or zoledronic acid have a delayed eruption age compared to a control group of healthy children. METHODS: An ambispective longitudinal cohort study evaluating the age of eruption of the first stage mixed dentition in a group of children with OI (n = 37) all treated with intravenous bisphosphonates compared with a group of healthy children (n = 89). Within the study group, the correlation (Pearson correlation test) between the type of medication administered (pamidronate and/or zoledronic acid) and the chronology of tooth eruption is established, as well as the relationship between the amount of cumulative dose received and tooth eruption. RESULTS: The age of eruption of the study group was significantly delayed compared to the age of eruption of the control group for molars and lateral incisors (p < 0.05). Patients who received higher cumulative doses had a delayed eruption age compared to those with lower cumulative doses (p < 0.05). There is a high positive correlation between age of delayed tooth eruption and Zoledronic acid administration. CONCLUSION: Patients with OI have a delayed eruption of the 1st stage mixed dentition compared to a control group of healthy children. This delayed eruption is directly related to the cumulative dose of bisphosphonates and the administration of zoledronic ac.

The IMPACT survey: a mixed methods study to understand the experience of children, adolescents and adults with osteogenesis imperfecta and their caregivers.

BACKGROUND: Osteogenesis imperfecta (OI) is a rare, heritable connective tissue disorder associated with a variety of symptoms, that affect individuals' quality of life (QoL) and can be associated with increased healthcare resource use. While some aspects of OI are well studied, others remain poorly understood. Therefore, the IMPACT survey aimed to elucidate the humanistic, clinical and economic burden of OI on individuals with OI, their families, caregivers and wider society. METHODS: We developed an international mixed methods online survey in eight languages (fielded July-September 2021), aimed at adults (aged ≥ 18 years) or adolescents (aged ≥ 12-17 years) with OI, caregivers (with or without OI) of individuals with OI and other close relatives. All respondents provided data on themselves; caregivers additionally provided data on individuals in their care by proxy. Data were cleaned, coded, and analysed using the pandas Python software package and Excel. RESULTS: IMPACT collected 2208 eligible questionnaires (covering 2988 individuals of whom 2312 had OI) including 1290 non-caregiver adults with OI, 92 adolescents with OI, 150 caregiver adults with OI, 560 caregivers for individuals with OI, 116 close relatives and 780 proxy care-recipients with OI. Most individuals with OI (direct or proxy) described their OI as moderate (41-52% across populations) and reported OI type 1 (33-38%). Pain (72-82%) was the most reported clinical condition experienced in the past 12 months and was also most frequently rated as severely or moderately impactful. Further, among adults, 67% reported fatigue, 47% scoliosis, and 46% sleep disturbance; in adolescents, fatigue affected 65%, scoliosis and other bone problems 60%, and mental health problems 46%; in children, fractures were common in 67%, fatigue in 47%, and dental problems in 46%. CONCLUSION: IMPACT has generated an extensive dataset on the experience of individuals with OI, their caregivers and relatives. We found that, irrespective of age, individuals with OI experience numerous and evolving symptoms that affect their QoL; however, pain and fatigue are consistently present. Upcoming analyses will provide further insights into the economic impact, healthcare journey and caregiver wellbeing, aiming to contribute to improved treatment and care for the OI community.

Short-term effects of Mediterranean diet on nutritional status in adults affected by Osteogenesis Imperfecta: a pilot study.

BACKGROUND: Osteogenesis Imperfecta (OI) is a heterogeneous group of connective tissue disorders, characterized by varying degrees of skeletal fragility. Patients experience a range of comorbidities, such as obesity, cardiovascular, and gastrointestinal complications, especially in adulthood. All aspects that could benefit from dietary intervention. The aim of this study was to evaluate the effects of a 6-months restricted Mediterranean Diet (rMD) on nutritional status in adult patients affected by OI. We carried out a 6-months longitudinal pilot study. 14 adults (median age: 35 years; 7 women; 7 OI type III) where recruited in 2019 among the members of As.It.O.I., the Italian Association of Osteogenesis Imperfecta. As.It.O.I. All the evaluations were performed at the University of Milan, Italy. The rMD provided a reduction of 30% from daily total energy expenditure. 45% of calories derived from carbohydrates, 35% from fat and 0.7-1.0 g/kg of body weight from proteins. Comparisons of continuous variables after 6 months of intervention were performed by the paired t-test. All P-values were two-tailed, and p < 0.05 was considered significant. RESULTS: Patients showed significant improvement in anthropometric measurements (BMI = 30.5 vs 28.1 kg/cm2, p < 0.001; Body Fat % = 32.9 vs 29.9, p = 0.006; Waist circumferences = 83.6 vs 79.6 cm; p < 0.001; Arm Fat Area = 29.8 vs 23.07 cm2; p < 0.011) and energy expenditure (REE/kg = 27.2 vs 29.2 kcal/kg, p < 0.001). Glucose and lipid profiles improved (Δglycemia = - 8.6 ± 7.3 mg/dL, p = 0.003; ΔTC = - 14.6 ± 20.1 mg/dL, p = 0.036; ΔLDL = - 12.0 ± 12.1 mg/dL, p = 0.009). Adherence to the MD significantly increased, moving from a moderate to a strong adherence and reporting an increased consumption of white meat, legumes, fish, nuts, fruits and vegetables. CONCLUSION: A rMD was effective in improving nutritional status and dietary quality in adults with OI. These results underscores the need to raise awareness of nutrition as part of the multidisciplinary treatment of this disease.

The impact of osteogenesis imperfecta severity on oral health-related quality of life in Spain: a cross-sectional study.

BACKGROUND: Osteogenesis imperfecta (OI) affects dental and craniofacial development; therefore, it can influence oral health-related quality of life (OHRQoL). The objective of this study was to explore the influence of the severity of OI on OHRQoL in adults older than eighteen years residing in Spain. METHOD: Adults with OI were recruited from the Spanish Association of Crystal Bone (AHUCE) foundation. OHRQoL was evaluated using the Spanish version of the Oral Health Impact Profile questionnaire (OHIP-14sp), oral hygiene habits, and a dental care survey. Clinical and radiological dental examinations were performed to evaluate the patients' oral conditions. RESULTS: A total of 65 adults (n = 46 females) aged between nineteen and sixty-two years who were diagnosed with OI and classified as type I, III, and IV (n = 20, 14, and 31, respectively) participated in this research. The total OHIP-14sp scores were significantly greater (worse) for type III (23 [SD = 10]) and type IV (21.4 [SD = 12]) than for type I (13.8 [SD = 6]) (P < 0.05). The negative impact of OHRQoL was due to the association of type III OI with all domains except for the handicap domain, while type IV OI was associated with the physical disability, social disability, and handicap domains (P < 0.05 for all). CONCLUSION: The severity of OI negatively impacted OHRQoL in adults. This association was statistically significant.

Otic Capsule Demineralization and Hearing Outcome of Stapes Surgery for Osteogenesis Imperfecta in Comparison With Otosclerosis.

OBJECTIVE: To assess the location/number of otic capsule demineralization and hearing outcomes of stapes surgery (SS) for osteogenesis imperfecta (OI) compared with otosclerosis (OS). PATIENTS: This study included 11 and 181 consecutive ears from 6 and 152 patients with OI and OS, respectively. INTERVENTIONS: Demineralization loci observed as hypodense area of the otic capsule were examined using high-resolution computed tomography. All patients underwent SS. MAIN OUTCOME MEASURES: Locations of the hypodense areas were classified into the anterior oval window, anterior internal auditory canal, and pericochlear area. The location/number of hypodense areas and preoperative/postoperative hearing parameters were correlated. Postoperative hearing outcome was evaluated 12 months after surgery. RESULTS: Hypodense area was more frequently observed in OI (9 of 11 ears [81.8%]) than in OS (96 of 181 ears [53.0%]), with significant differences. Multiple sites were involved in 81.8% OI and 18.8% OS patients, showing significant differences. Preoperative air conduction (AC), bone conduction, and air-bone gap (ABG) were 48.9 ± 17.8, 28.0 ± 11.3, and 20.7 ± 8.4 dB, respectively, in OI and 56.2 ± 13.5, 30.5 ± 9.9, and 26.4 ± 9.7 dB, respectively, in OS, demonstrating greater AC and ABG in OS than in OI. Postoperative AC (31.3 ± 20.5 dB), ABG (10.6 ± 10.0 dB), and closure of ABG (12.1 ± 4.7 dB), that is, preoperative ABG minus postoperative ABG of OI, were comparable to those of OS (AC, 30.9 ± 13.3 dB; ABG, 7.0 ± 7.4 dB; closure of ABG, 20.1 ± 11.6 dB). CONCLUSION: OI ears showed more severe demineralization of otic capsule than OS ears. However, favorable hearing outcomes could be obtained through SS for OI and OS ears.

The impact of craniofacial and dental osteogenesis imperfecta manifestations on oral health-related quality of life of children and adolescents.

OBJECTIVE: Craniofacial and oral manifestations of Osteogenesis Imperfecta (OI) can affect the functioning of the stomatognathic system and impact the patient's quality of life. The objective of the study was to evaluate the relationship between craniofacial and oral manifestations and the Oral Health-related Quality of Life (OHRQoL) of OI children and adolescents. MATERIAL AND METHODS: A total of 30 OI patients aged eight to fourteen years old followed up at the Oral Care Center for Inherited Diseases were enrolled in the research. OHRQoL was assessed using the short form of the Child Perceptions Questionnaire (CPQ) for eight to ten-year-olds (CPQ8-10) and 11 to 14-year-olds (CPQ11-14). The relationship between the OHRQoL index and its assessment domains, OI types, and the presence of dentinogenesis imperfecta (DI), class III malocclusion, and dental agenesis were evaluated. RESULTS: The median CPQ score of patients was 5, and there was no significant difference in OHRQoL between children and adolescents, nor associated with the disease severity or the presence of DI. The oral manifestations evaluated did not directly impact the patients' OHRQoL. CONCLUSIONS: The study demonstrated that the perception of OHRQoL is similar for both adolescents and children. The oral symptom was the most relevant domain for the index among patients aged eight to fourteen years while the emotional well-being was the most impacted. CLINICAL RELEVANCE: this study makes contributions by indicating that addressing dental care for children and adolescents with OI is important in clinical management and better OHRQoL for this population.

Characteristics of femoral neck fractures in osteogenesis imperfecta: Series of four-teen consecutive hips in twelve patients.

INTRODUCTION: While long bone fractures are commonly seen in individuals with Osteogenesis Imperfecta (OI), femoral neck fractures (FNF) are exceedingly rare. There is a lack of comprehensive data regarding the etiology of FNFs, their characteristics, and the treatment protocols. Our aim was to determine the characteristics of femoral neck fractures in children with OI. MATERIALS AND METHODS: This study was conducted as retrospective series covering period of January 2011-December 2022. Total of 14 femoral neck fractures in 12 patients were included into final analysis. Age, gender, fracture location, ambulation level, injury mechanism, Sillence type, pre-fracture collo-diaphyseal angle, presence of previous implants and applied treatments were noted. RESULTS: The mean age was 9.3 (range: 3-16), 8 out of 12 patients were males. Sillence type 3 OI was most common (50 %) type. Among 12 patients, 2 (16.6 %) were restricted ambulatory while 5 (41.6 %) were non-ambulatory. Seven patients had prior femoral implants. Six fractures were managed non-operatively, while others underwent surgery, with cannulated screws (42.8 %) or plate osteosynthesis (7.1 %). All eight cases (100 %) with minor trauma or unknown origin were Sillence type 3-4, displaying varus deformity. FNFs that occured in mobile patients required higher-energy traumas. CONCLUSION: Femoral neck fractures in OI showed differing trauma mechanisms in ambulatory vs. non-ambulatory patients. Non-surgical treatment may be considered with in patients with high-risk anesthesia concerns, requiring higher level clinical studies.

Surgical treatment of osteogenesis imperfecta: a summary of the incidence of femoral implant-related complications in children with Sillence type I, III and IV.

PURPOSE: This study explored the incidence of IRCs used in the procedures of the femur in children with osteogenesis imperfecta (OI) and investigated the independent risk factors of IRCs. METHODS: Three hundred eight-eight cases of surgical data about children with OI were included, who were treated with plate, elastic nail, Kirschner wire and telescopic rod. The choice of different procedures depended on the age of children, the status of femur and the availability of devices. Patient demographics and major IRCs were recorded to compare the outcomes of the four procedures. Then, Cox proportional hazard regression was used to analyse the independent risk factors of IRC, and subgroup analysis was applied to further verify the above results. RESULTS: The total incidence of IRC in the four groups was 90.1% (191/212) for plate, 96.8% (30/31) for Kirschner wire, 87.7% (57/65) for elastic nail and 30.0% (24/80) for telescopic rod. The incidence of IRC in the telescopic rod was lower than that in plate, elastic nail and Kirschner wire (P < 0.001). Cox proportional hazard regression analysis confirmed that procedure was the independent risk factor of IRC (HR, 0.191; 95% CI, 0.126-0.288; P < 0.001), fracture (HR, 0.193; 95% CI, 0.109-0.344; P < 0.001) and deformity (HR, 0.086; 95% CI, 0.027-0.272; P < 0.001). In addition, age of surgery was the independent risk factor of fracture (HR, 0.916; 95% CI, 0.882-0.952; P < 0.001) and deformity (HR, 1.052; 95% CI, 1.008-1.098; P = 0.019). Subgroup analysis confirmed that age of surgery, gender, classification, preoperative state and angle did not affect the effect of telescopic rod on reducing the risk of IRCs. CONCLUSIONS: In our cohort, lower incidence of IRCs was observed in telescopic rod group compared with plate, Kirschner wire and elastic nail. Procedure and age of surgery were independent risk factors of fracture. Likewise, procedure and age of surgery were independent risk factors of deformity, and procedure was independent risk factors of IRC.

Bleeding assessment in a large cohort of patients with Osteogenesis Imperfecta.

BACKGROUND: Osteogenesis Imperfecta (OI) is characterised by bone fragility. Among several features, easy bruising and multiple case reports on haemorrhagic events have been reported. This paper describes the diverse manifestations of bleeding and bruising in a large cohort of 328 OI patients. The aim of this study is to provide insight in the diverse aspects and therapeutic considerations of bleedings in OI. METHODS: This descriptive cohort study was conducted at the National Expert Center for adults with OI in the Netherlands. Bleeding was assessed by the validated self-bleeding assessment tool (Self-BAT) The tool was distributed among 328 adults with different clinically confirmed types of OI. RESULTS: 195 of 328 invited patients (completion rate 60%) with OI type 1 (n = 144), OI type 3 (n = 17) and OI type 4 (n = 34), aged between 18 and 82 years, completed the tool. Self-BAT scores were above the normal range in 42% of all patients. For males Self-BAT scores were increased in 37% with a mean score of 3.7, ranged between 0 and 18. For females the Self-BAT scores were increased in 44% with a mean of 5.4 and a range of 0-24. No statistical differences in OI subtypes were found. CONCLUSIONS: Bleeding tendency appears to be a relevant complication in OI patients as this study confirms the presumption of bleeding tendency. There are specific recommendations to clinicians who treat OI patients to consider an assessment of bleeding tendency and use potential interventions to reduce haemorrhagic complications and improve quality of life.

Cranio-cervical abnormalities in moderate-to-severe osteogenesis imperfecta - Genotypic and phenotypic determinants.

INTRODUCTION: Cranio-cervical anomalies are significant complications of osteogenesis imperfecta (OI), a rare bone fragility disorder that is usually caused by mutations in collagen type I encoding genes. OBJECTIVE: To assess cranio-cervical anomalies and associated clinical findings in patients with moderate-to-severe OI using 3D cone beam computed tomography (CBCT) scans. METHODS: Cross-sectional analysis of CBCT scans in 52 individuals with OI (age 10-37 years; 32 females) and 40 healthy controls (age 10-32 years; 26 females). Individuals with a diagnosis of OI type III (severe, n = 11), type IV (moderate, n = 33) and non-collagen OI (n = 8) were recruited through the Brittle Bone Disorders Consortium. Controls were recruited through the orthodontic clinic of the University of Missouri-Kansas City (UMKC). RESULTS: OI and control groups were similar in mean age (OI: 18.4 [SD: 7.2] years, controls: 18.1 [SD: 6.3] years). The cranial base angle was increased in the OI group (OI: mean 148.6° [SD: 19.3], controls: mean 130.4° [SD: 5.7], P = .001), indicating a flatter cranial base. Protrusion of the odontoid process into the foramen magnum (n = 7, 14%) and abnormally located odontoid process (n = 19, 37%) were observed in the OI group but not in controls. Low stature, expressed as height z-score (P = .01), presence of DI (P = .04) and being male (P = .04) were strong predictors of platybasia, whereas height z-score (P = .049) alone was found as positive predictor for basilar impression as per the Chamberlain measurement. CONCLUSION: The severity of the phenotype in OI, as expressed by the height z-score, correlates with the severity of cranial base anomalies such as platybasia and basilar impression in moderate-to-severe OI. Screening for cranial base anomalies is advisable in individuals with moderate-to-severe OI, with special regards to the individuals with a shorter stature and DI.

Efficacy of Bisphosphonate for Urolithiasis Complicated by Osteogenesis Imperfecta.

A 44-year-old man with osteogenesis imperfecta presented with left renal colic. Non-contrast computed tomography revealed a stone (10×9 mm) in the left upper ureter. Ureteroscopic lithotripsy was performed twice and stone-free status was achieved. An analysis of the stone revealed a mixed composition including calcium oxalate and calcium phosphate. Postoperatively, we administered bisphosphonates to prevent recurrence of urolithiasis, as 24-hour urine collection revealed marked hypercalciuria. Eighteen months after surgery, the urinary calcium levels had normalized, and there was no recurrence of urolithiasis. Osteogenesis imperfecta can be complicated by urolithiasis, but bisphosphonates may be useful in preventing recurrence of this disease.

Reducing fracture incidence in children with osteogenesis imperfecta: contribution of orthotics to bisphosphonates treatment.

PURPOSE: To determine whether there was a reduction in fracture incidence amongst children with OI who were treated with both bisphosphonates and orthoses. OBJECTIVE: Was there an additional reduction in fracture incidence amongst children with Osteogenesis Imperfecta (OI) treated with both bisphosphonates and Hip-Knee-Ankle-Foot-Orthosis (HKAFO)? MATERIALS AND METHODS: Of the 129 OI patients treated from 1990 to 2017, retrospective data from 48 patients who participated in the bisphosphonates-orthosis regime were analyzed including the incidence of fractures and modalities of fracture treatment. RESULTS: Bisphosphonates usage was more frequent than bracing and there were more positive changes (smaller or equal number of fractures each year) than negative changes (more fractures each year); negative changes were scarce, explained by non-compliance with the use of bracing. Poisson regression models were significant for positive changes, whereas the interaction between them was borderline significant. The main finding is that the association between bisphosphonates usage and the number of positive changes was stronger among the patients who used braces more frequently and weaker among patients who used bracing less frequently. CONCLUSIONS: Bracing of OI patients has an additive effect on bisphosphonate treatment in fracture prevention which should lead to the reconsideration of a hybrid approach to OI management.

Two key goals of treatment of Osteogenesis Imperfecta (OI) patients include decreasing fracture incidence and improving function and independence as supported by a multi-disciplinary approach that combines medical, orthopaedic and rehabilitation treatments.Although the literature provides evidence that bisphosphonates reduce the frequency of fractures, there have not been reports of its effect when used with orthoses.Orthoses for OI patients have an additive effect on bisphosphonate treatment in fracture prevention.These results contribute to making an informed decision regarding this hybrid approach to OI management.

[Features and results of surgical rehabilitation of hearing loss in osteogenesis imperfecta]. / Osobennosti i rezul'taty khirurgicheskogo lecheniya tugoukhosti pri nesovershennom osteogeneze.

Osteogenesis imperfecta (OI) is a form of congenital osteoporosis. Depending on the type of OI, patients experience various types of hearing loss. Depending on the type and degree of hearing loss, various methods of hearing rehabilitation are used in this category of patients. OBJECTIVE: To evaluate the features and results of surgical rehabilitation of hearing loss in patients with osteogenesis imperfecta. MATERIAL AND METHODS: During the period from 2009 to 2022, 2221 primary stapedoplasty was performed in the department, of which 23 (1.04%) in 21 patients were performed in patients with OI. There were 14 women and 7 men. According to TPA, bilateral hearing loss was detected in 19 patients and unilateral in 2. Conductive hearing loss was observed in 9 cases and mixed - in 14. The average thresholds for bone conduction (BC) were 22.7±8.04 dB, and the bone-air interval (ABG) - 36.1±5.3 dB. According to CT of the temporal bones, all patients showed a bilateral and symmetrical decrease in the density of the auditory ossicles, and in 7 patients there were extensive areas of non-uniform decrease in the density of the bone labyrinth up to +500 - +1000 HU.21 patients underwent 23 operations: in 21 cases stapedoplasty with laser assistance and in 2 cases ossiculoplasty. RESULTS: BC thresholds 6 months after surgery averaged 24.6±8.2 dB, and ABG - 12.1±2.9 dB. Closing of ABG ≤10 dB at spoken frequencies was detected in 30.5%, ABG ≤20 dB - in 95%. After 12 months or more after the operation, no change in the audiological parameters was noted. CONCLUSIONS: Stapes surgery for conductive and mixed hearing loss in OI patients is functionally effective. The best results are achieved after therapy with bisphosphonates with preparations of sodium fluoride, calcium and vitamin D, performing the operation when the density of demineralization zones reaches 1000 HU and using laser assistance. Taking into account the demineralization of the bone structures of the temporal bone, it is recommended to use autocartilaginous stirrup prostheses to restore sound conduction or to cover the attachment area of other prostheses with autologous tissues to prevent necrosis of the long stalk of the incus and stabilize long-term functional results.

Monochorionic twin pregnancy in a patient with type III osteogenesis imperfecta: a multidisciplinary challenge.

A woman with severe type III osteogenesis imperfecta spontaneously conceived a monochorionic, diamniotic twin pregnancy. Due to the severity of her condition, her pregnancy required close follow-up involving a multidisciplinary team, including high-risk obstetricians, anaesthetists, pulmonologists and respiratory therapists. Eventually, the twins were delivered via caesarean section at 26 weeks' gestation.We discuss the challenges and considerations in managing her high-risk pregnancy, highlighting the importance of multidisciplinary care in achieving a safe outcome for mother and babies.

Protocol of a randomised trial of teriparatide followed by zoledronic acid to reduce fracture risk in adults with osteogenesis imperfecta.

INTRODUCTION: Osteogenesis imperfecta (OI) is a rare genetic disease associated with multiple fractures throughout life. It is often treated with osteoporosis medications but their effectiveness at preventing fractures is unknown. The Treatment of Osteogenesis Imperfecta with Parathyroid Hormone and Zoledronic Acid trial will determine if therapy with teriparatide (TPTD) followed by zoledronic acid (ZA) can reduce the risk of clinical fractures in OI. METHODS AND ANALYSIS: Individuals aged ≥18 years with a clinical diagnosis of OI are eligible to take part. At baseline, participants will undergo a spine X-ray, and have bone mineral density (BMD) measured by dual-energy X-ray absorptiometry (DXA) at the spine and hip. Information on previous fractures and previous bone targeted treatments will be collected. Questionnaires will be completed to assess pain and other aspects of health-related quality of life (HRQoL). Participants will be randomised to receive a 2-year course of TPTD injections 20 µg daily followed by a single intravenous infusion of 5 mg ZA, or to receive standard care, which will exclude the use of bone anabolic drugs. Participants will be followed up annually, have a repeat DXA at 2 years and at the end of study. Spine X-rays will be repeated at the end of study. The duration of follow-up will range between 2 and 8 years. The primary endpoint will be new clinical fractures confirmed by X-ray or other imaging. Secondary endpoints will include participant reported fractures, BMD and changes in pain and HRQoL. ETHICS AND DISSEMINATION: The study received ethical approval in December 2016. Following completion of the trial, a manuscript will be submitted to a peer-reviewed journal. The results will inform clinical practice by determining if TPTD/ZA can reduce the risk of fractures in OI compared with standard care. TRIAL REGISTRATION NUMBER: ISRCTN15313991.