Imaging of Metabolic Bone Diseases: The Spine View, Part I.

Metabolic bone diseases comprise a wide spectrum. Of them, osteoporosis is the most frequent and the most commonly found in the spine, with a high impact on health care systems and on morbidity due to vertebral fractures (VFs).This article discusses state-of-the-art techniques on the imaging of metabolic bone diseases in the spine, from the well-established methods to the latest improvements, recent developments, and future perspectives.We review the classical features of involvement of metabolic conditions involving the spine. Then we analyze the different imaging techniques for the diagnosis, characterization, and monitoring of metabolic bone disease: dual-energy X-ray absorptiometry (DXA) and DXA-based fracture risk assessment applications or indexes, such as the geometric parameters, Bone Strain Index, and Trabecular Bone Score; quantitative computed tomography; and magnetic resonance and ultrasonography-based techniques, such as radiofrequency echographic multi spectrometry. We also describe the current possibilities of imaging to guide the treatment of VFs secondary to metabolic bone disease.

Imaging of Metabolic Bone Diseases: The Spine View, Part II.

Metabolic bone diseases comprise a wide spectrum. Osteoporosis, the most frequent, characteristically involves the spine, with a high impact on health care systems and on the morbidity of patients due to the occurrence of vertebral fractures (VFs).Part II of this review completes an overview of state-of-the-art techniques on the imaging of metabolic bone diseases of the spine, focusing on specific populations and future perspectives. We address the relevance of diagnosis and current status on VF assessment and quantification. We also analyze the diagnostic techniques in the pediatric population and then review the assessment of body composition around the spine and its potential application. We conclude with a discussion of the future of osteoporosis screening, through opportunistic diagnosis and the application of artificial intelligence.

What happens to the lower lumbar spine after marathon running: a 3.0 T MRI study of 21 first-time marathoners.

OBJECTIVE: To better understand the impact of long-distance running on runners' lumbar spines by assessing changes before and after their first marathon run. MATERIALS AND METHODS: The lumbar spines of 28 asymptomatic adults (14 males, 14 females, mean age: 30 years old), who registered for their first marathon, the 2019 London Richmond Marathon, were examined 16 weeks before (time point 1) and 2 weeks after (time point 2) the marathon. Participants undertook a pre-race 16-week training programme. Magnetic resonance imaging (MRI) of high-resolution 3.0 Tesla was used at each time point. Senior musculoskeletal radiologists assessed the lower lumbar spine condition. RESULTS: Out of 28 participants, 21 completed both the training and the race and 7 neither completed the training nor started the marathon but not due to spine-related issues. At time point 1, disc degeneration was detected in 17/28 (61%), most predominantly at spinal segments L4-L5 and L5-S1. No back pain/other symptoms were reported. When compared to time point 2, there was no progression in the extent of disc degeneration, including intervertebral disc (IVD) height (p = 0.234), width (p = 0.359), and intervertebral distance (p = 0.641). There was a regression in 2 out of 8 (25%) participants who had pre-marathon sacroiliac joint bone marrow oedema, and a small increase in the size of a pre-marathon subchondral cyst in one participant, all asymptomatic. CONCLUSION: Running 500 miles over 4 months plus a marathon for the first time had no adverse effects on the lumbar spine, even when early degenerative changes were present. Additionally, there was evidence of regression of sacroiliac joint abnormalities.

Automated multi-atlas segmentation of gluteus maximus from Dixon and T1-weighted magnetic resonance images.

OBJECTIVE: To design, develop and evaluate an automated multi-atlas method for segmentation and volume quantification of gluteus maximus from Dixon and T1-weighted images. MATERIALS AND METHODS: The multi-atlas segmentation method uses an atlas library constructed from 15 Dixon MRI scans of healthy subjects. A non-rigid registration between each atlas and the target, followed by majority voting label fusion, is used in the segmentation. We propose a region of interest (ROI) to standardize the measurement of muscle bulk. The method was evaluated using the dice similarity coefficient (DSC) and the relative volume difference (RVD) as metrics, for Dixon and T1-weighted target images. RESULTS: The mean(± SD) DSC was 0.94 ± 0.01 for Dixon images, while 0.93 ± 0.02 for T1-weighted. The RVD between the automated and manual segmentation had a mean(± SD) value of 1.5 ± 4.3% for Dixon and 1.5 ± 4.8% for T1-weighted images. In the muscle bulk ROI, the DSC was 0.95 ± 0.01 and the RVD was 0.6 ± 3.8%. CONCLUSION: The method allows an accurate fully automated segmentation of gluteus maximus for Dixon and T1-weighted images and provides a relatively accurate volume measurement in shorter times (~ 20 min) than the current gold-standard manual segmentations (2 h). Visual inspection of the segmentation would be required when higher accuracy is needed.

Prevalence of abnormal findings in 230 knees of asymptomatic adults using 3.0 T MRI.

OBJECTIVE: To identify abnormalities in asymptomatic sedentary individuals using 3.0 Tesla high-resolution MRI. MATERIALS AND METHODS: The cohort comprised of 230 knees of 115 uninjured sedentary adults (51 males, 64 females; median age: 44 years). All participants had bilateral knee 3.0 T MRIs. Two senior musculoskeletal radiologists graded all intraarticular knee structures using validated scoring systems. Participants completed Knee Injury and Osteoarthritis Outcome Score questionnaires at the time of the MRI scan. RESULTS: MRI showed abnormalities in the majority (97%) of knees. Thirty percent knees had meniscal tears: horizontal (23%), complex (3%), vertical (2%), radial (2%) and bucket handle (1%). Cartilage and bone marrow abnormalities were prevalent at the patellofemoral joint (57% knees and 48% knees, respectively). Moderate and severe cartilage lesions were common, in 19% and 31% knees, respectively, while moderate and severe bone marrow oedema in 19% and 31% knees, respectively. Moderate-intensity lesion in tendons was found in 21% knees and high-grade tendonitis in 6% knees-the patellar (11% and 2%, respectively) and quadriceps (7% and 2%, respectively) tendons being most affected. Three percent partial ligamentous ruptures were found, especially of the anterior cruciate ligament (2%). CONCLUSION: Nearly all knees of asymptomatic adults showed abnormalities in at least one knee structure on MRI. Meniscal tears, cartilage and bone marrow lesions of the patellofemoral joint were the most common pathological findings. Bucket handle and complex meniscal tears were reported for the first time in asymptomatic knees.

Is the immediate effect of marathon running on novice runners' knee joints sustained within 6 months after the run? A follow-up 3.0 T MRI study.

OBJECTIVE: To evaluate changes in the knee joints of asymptomatic first-time marathon runners, using 3.0 T MRI, 6 months after finishing marathon training and run. MATERIALS AND METHODS: Six months after their participation in a baseline study regarding their knee joints, 44 asymptomatic novice marathoners (17 males, 27 females, mean age 46 years old) agreed to participate in a repeat MRI investigation: 37 completed both a standardized 4-month-long training programme and the marathon (marathon runners); and 7 dropped out during training (pre-race dropouts). The participants already underwent bilateral 3.0 T MRIs: 6 months before and 2 weeks after their first marathon, the London Marathon 2017. This study was a follow-up assessment of their knee joints. Each knee structure was assessed using validated scoring/grading systems at all time points. RESULTS: Two weeks after the marathon, 3 pre-marathon bone marrow lesions and 2 cartilage lesions showed decrease in radiological score on MRI, and the improvement was sustained at the 6-month follow-up. New improvements were observed on MRI at follow-up: 5 pre-existing bone marrow lesions and 3 cartilage lesions that remained unchanged immediately after the marathon reduced in their extent 6 months later. No further lesions appeared at follow-up, and the 2-week post-marathon lesions showed signs of reversibility: 10 of 18 bone marrow oedema-like signals and 3 of 21 cartilage lesions decreased on MRI. CONCLUSION: The knees of novice runners achieved sustained improvement, for at least 6 months post-marathon, in the condition of their bone marrow and articular cartilage.

Quantitative 3D analysis of bone in hip osteoarthritis using clinical computed tomography.

OBJECTIVE: To assess the relationship between proximal femoral cortical bone thickness and radiological hip osteoarthritis using quantitative 3D analysis of clinical computed tomography (CT) data. METHODS: Image analysis was performed on clinical CT imaging data from 203 female volunteers with a technique called cortical bone mapping (CBM). Colour thickness maps were created for each proximal femur. Statistical parametric mapping was performed to identify statistically significant differences in cortical bone thickness that corresponded with the severity of radiological hip osteoarthritis. Kellgren and Lawrence (K&L) grade, minimum joint space width (JSW) and a novel CT-based osteophyte score were also blindly assessed from the CT data. RESULTS: For each increase in K&L grade, cortical thickness increased by up to 25 % in distinct areas of the superolateral femoral head-neck junction and superior subchondral bone plate. For increasing severity of CT osteophytes, the increase in cortical thickness was more circumferential, involving a wider portion of the head-neck junction, with up to a 7 % increase in cortical thickness per increment in score. Results were not significant for minimum JSW. CONCLUSIONS: These findings indicate that quantitative 3D analysis of the proximal femur can identify changes in cortical bone thickness relevant to structural hip osteoarthritis. KEY POINTS: • CT is being increasingly used to assess bony involvement in osteoarthritis • CBM provides accurate and reliable quantitative analysis of cortical bone thickness • Cortical bone is thicker at the superior femoral head-neck with worse osteoarthritis • Regions of increased thickness co-locate with impingement and osteophyte formation • Quantitative 3D bone analysis could enable clinical disease prediction and therapy development.

Skeletal Manifestations of Osteogenesis Imperfecta.

The skeletal manifestations of osteogenesis imperfecta are investigated. The antenatal and postnatal diagnosis of the disease is briefly mentioned and the characteristic appearances of bone deformities are analyzed in detail. The distinctive bony manifestations of osteogenesis imperfecta are illustrated using typical examples. Finally, we comment on the differential diagnosis.

Imaging of the Painful Hip Arthroplasty.

The incidence of complications following total hip arthroplasty is low, but due to the frequency of the procedure, they are quite commonly encountered and require appropriate investigation. Complications include aseptic loosening, infection, foreign body granulomatosis (osteolysis), adverse reactions to metal debris, periprosthetic fracture, heterotopic ossification, hardware failure, and a range of soft tissue complications, all of which may result in pain. Relevant imaging findings are illustrated and the role of various imaging modalities is reviewed. A suggested approach for the radiological investigation of each potential complication is outlined, based on our experience at a specialist referral unit.

Pancreatic cancer with synchronous peritoneal and hepatic metastases: A case report.

Introduction and importance: There is evidence that patients with limited peritoneal carcinomatosis of pancreatic cancer or those with low burden of hepatic metastases are amenable to surgical resection. A case report of a patient with cancer of the pancreatic tail and synchronous peritoneal and hepatic metastases is presented. CASE PRESENTATION: A male patient, 66 years old, underwent cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) and radio-frequency ablation (RFA) for synchronous hepatic metastases simultaneously to distal pancreatectomy for adenocarcinoma of the pancreas. Adjuvant chemotherapy followed the R0 surgery. The patient remained disease free for 18 months, developed liver recurrence and died 28 months after the initial operation. DISCUSSION: CRS plus HIPEC with synchronous ablation or resection of hepatic metastases may be used for the treatment of pancreatic cancer with synchronous peritoneal and hepatic metastases in highly selected patients. CONCLUSION: Further studies are needed to confirm whether patients with synchronous peritoneal and hepatic metastases are offered survival benefit from complex surgical intervention (CRS plus HIPEC combined with hepatic resection or RFA).

Subchondral impaction fractures of the non-weight-bearing portion of the lateral femoral condyle.

OBJECTIVE: To document the first report of intra-articular, non-weight-bearing, impaction fractures of the lateral femoral condyle. MATERIALS & METHODS: Institutional Review Board and Regional Ethics Committee approval for this study was obtained and patient informed consent deemed unnecessary. We prospectively documented all potential cases of non-weight-bearing posterior subchondral impaction fractures of the femoral condyles diagnosed on magnetic resonance imaging (MRI) of the knee performed at our institution between January 2006 and December 2011. The cases were reviewed and discussed by three experienced musculoskeletal radiologists and only cases satisfying pre-defined MRI criteria were included. RESULTS: Sixteen cases of intra-articular impaction fractures in a posterior, non-weight-bearing area of the lateral femoral condyle were diagnosed in patients with a mean age of 40. Eight were associated with recreational sports activities and 4 with repeated kneeling. There were no fractures documented in the non-weight-bearing aspect of the medial femoral condyles. Proposed underlying mechanisms for development of this type of fracture are presented. CONCLUSION: Awareness, along with a high level of suspicion, that non-specific knee pain, especially in patients involved in athletic activities, could be due to intra-articular impaction fractures of the non-weight-bearing posterior aspect of the lateral femoral condyle is essential and MRI is the mainstay of diagnosis.

Management of low back pain with facet joint injections and nerve root blocks under computed tomography guidance. A prospective study.

OBJECTIVES: The aim of this work was to assess the performance of facet joint and nerve root infiltrations under computed tomography guidance for the management of low back pain and to investigate the complications and patient tolerance. MATERIALS AND METHODS: The study was board-certified and informed consent was obtained from all patients. In 1 year, 86 consecutive patients (47 male, 39 female, age range 47-87 years, mean age 63) with low back pain for more than 2 years were included. All patients were clinically examined and had cross-sectional imaging performed before the procedure. Fifty-five facet joint infiltrations and 31 nerve blocks were performed under computed tomography guidance. All patients completed two valid pain questionnaires before and 3 months after the procedures. At the same time, they were clinically examined by the referring Orthopaedic Surgeon. The pain response was assessed by comparing the scores of the questionnaires. The improvement in clinical examination findings was assessed as well. RESULTS: In patients who underwent facet joint infiltrations, long-term pain improvement was achieved in 79% and in those with nerve blocks in 85%. Immediate pain relief was demonstrated in 83% of patients with nerve infiltrations. No complications were observed. All procedures were very well tolerated by patients. CONCLUSIONS: Facet joint and nerve infiltrations under computed tomography guidance constitute an accurate and safe method that could be used to relieve low back pain and minimize the risk of disability.

Ossicles of lumbar articular facets: normal variant or spondylolytic variant?

PURPOSE: The objective of this study was to establish the prevalence and significance of ossicles of lumbar articular facets (OLAF) in young athletes with backache diagnosed by multi-detector computed tomography (MDCT). MATERIALS AND METHODS: The MDCT examinations of the lumbar spine carried out for suspected spondylolysis on 46 consecutive symptomatic young athletes presenting to a sports injury clinic over a 1-year period were retrospectively reviewed. OLAF study included detailed correlation with the structural and morphological stress features of the posterior neural arches. This was then compared with a control group composed of 39 patients. RESULTS: Twenty-three OLAF were identified in 15 patients. Eleven of the 15 patients with ossicles had posterior element stress changes (PEST)/pars defects. In the control group, two OLAF were identified in two patients, one demonstrating PEST changes. CONCLUSION: The high prevalence of OLAF in young symptomatic athletes compared with the asymptomatic control group is indicative of stress fractures. The non-united articular process fractures should be regarded as part of the spectrum of stress-induced changes in the posterior neural arch in the same way as spondylolysis. MDCT with volumetric acquisition and multi-planar reformation is the most reliable investigation in the diagnosis of OLAF. KEY POINTS: 1) This CT study supports a traumatic aetiology for lumbar articular facets ossicles. 2) OLAF represent part of a spectrum of stress-induced changes in the posterior neural arch. 3) OLAF are associated with typical spondylolysis. 4) OLAF can be overlooked on reverse gantry angle computed tomography (RG-CT). 5) OLAF may account for some of the discrepancy between radionuclide and RG-CT studies.

Functional outcome and structural integrity following mini-open repair of large and massive rotator cuff tears: a 3-5 year follow-up study.

BACKGROUND: Mini-open approach has been considered for years the gold standard for rotator cuff repairs. Nevertheless, the rate of tendon-to-bone healing, and that of cuff re-tear, still remains unclear. METHODS: Between 2001 and 2004, 37 shoulders (32 patients) with a mean age of 54.8 years (range, 34-72) and a large or massive cuff tear were repaired with a mini-open procedure. At a minimum of 3 years postoperatively (range, 36-60 months), 27 shoulders (23 patients) underwent functional evaluation and US investigation of cuff integrity. RESULTS: The rotator cuff was completely healed and watertight in 13 cases (48.1%), while recurrent defects were detected in the remaining 14 shoulders (51.9%). In 12 cases (92.5%), the recurrent tears were smaller and in 2 (7.5%) larger than the initial tear. Despite the high re-tear rate, the overall Constant and UCLA scores improved from of 38.4 to 72.1 and 11.2 to 29.4, respectively. However, only "large" re-tears were correlated with a worse functional outcome (P < .005). The preoperative tear size was negatively associated with tendon healing. Patients with an intact rotator cuff repair were, on average, 15 years younger (49.9) than those who sustained a tear recurrence (64.14) (P < .005). DISCUSSION: Our results suggest that large and massive rotator cuff tears treated with mini-open technique using a tendon-grasping suture have a very satisfactory clinical outcome, despite a significant re-tear rate. Patient age, the size of the initial tear, as well as the size of a potential re-tear are factors affecting the final clinical outcome.

3.0 T MRI findings of 104 hips of asymptomatic adults: from non-runners to ultra-distance runners.

OBJECTIVES: To determine and compare the health status of hip joints of individuals undertaking various lengths of long-distance running and of those who are not running. METHODS: Fifty-two asymptomatic volunteers underwent bilateral hip 3.0 Tesla MRI: (1) 8 inactive non-runners; (2) 28 moderately active runners (average half a marathon (21 km)/week) and (3) 16 highly active runners (≥ marathon (42 km)/week). Two musculoskeletal radiologists reported the hip MRI findings using validated scoring systems. Study participants completed a Hip disability and Osteoarthritis Outcome Score (HOOS) questionnaire to indicate their perceived hip function. RESULTS: The MRI findings show that there were no significant differences among inactive non-runners, moderately active runners and highly active runners in the amount of labral abnormalities (p=0.327), articular cartilage lesions (p=0.270), tendon abnormalities (p=0.141), ligament abnormalities (p=0.519). Bone marrow oedema was significantly more common in moderately active runners than in non-runners and highly active runners (p=0.025), while small subchondral cysts were more common in runners than in non-runners (p=0.017), but these were minor/of small size, asymptomatic and did not indicate specific exercise-related strain. Articular cartilage lesions and bone marrow oedema were not found in highly active runners. HOOS scores indicate no hip symptoms or functional problems among the three groups. CONCLUSION: The imaging findings were not significantly different among inactive non-runners, moderately active runners and highly active runners, in most hip structures, suggesting that long-distance running may not add further damage to the hip joints.

Magnetic Resonance Imaging of the Hips of Runners Before and After Their First Marathon Run: Effect of Training for and Completing a Marathon.

BACKGROUND: No studies have focused on magnetic resonance imaging (MRI) of the hips of marathoners, despite the popularity and injury risks of marathon running. PURPOSE: To understand the effect of preparing for and completing a marathon run (42 km) on runners' hip joints by comparing MRI findings before and after their first marathon. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 28 healthy adults (14 males, 14 females; mean age, 32.4 years) were recruited after registering for their first marathon. They underwent 3-T MRI of both hips at 16 weeks before (time point 1) and 2 weeks after the marathon (time point 2). After the first MRI, 21 runners completed the standardized, 4 month--long training program and the marathon; 7 runners did not complete the training or the marathon. Specialist musculoskeletal radiologists reported and graded the hip joint structures using validated scoring systems. Participants completed the Hip disability and Osteoarthritis Outcome Score (HOOS) at both imaging time points. RESULTS: At time point 1, MRI abnormalities of the hip joint were seen in 90% of participants and were located in at least 1 of these areas: labrum (29%), articular cartilage (7%), subchondral bone marrow (14%), tendons (17%), ligaments (14%), and muscles (31% had moderate muscle atrophy). At time point 2, only 2 of the 42 hips showed new findings: a small area of mild bone marrow edema appearance (nonweightbearing area of the hip and not attributable to running). There was no significant difference in HOOS between the 2 time points. Only 1 participant did not finish the training because of hip symptoms and thus did not run the marathon; however, symptoms resolved before the MRI at time point 2. Six other participants discontinued their training because of non-hip related issues: a knee injury, skin disease, a family bereavement, Achilles tendon injury, illness unrelated to training, and a foot injury unrelated to training. CONCLUSION: Runners who completed a 4-month beginner training program before their first marathon run, plus the race itself, showed no hip damage on 3-T MRI scans.

Accessory flexor carpi ulnaris: case report and review of the literature.

Most of the accessory muscles of the forearm described in the radiology literature are located either in the radial aspect of the forearm or towards the hypothenar eminence. We present an unusual case of an ulnar-sided distal forearm accessory flexor carpi ulnaris muscle presenting as a "pseudotumour" demonstrated with both ultrasound and MRI, rarely reported in the current surgical and anatomical literature. Given the location and relation to the ulnar nerve towards Guyon's canal, the accessory muscle may also predispose to distal ulnar nerve entrapment.

Automated measurement of fat infiltration in the hip abductors from Dixon magnetic resonance imaging.

PURPOSE: Intramuscular fat infiltration is a dynamic process, in response to exercise and muscle health, which can be quantified by estimating fat fraction (FF) from Dixon MRI. Healthy hip abductor muscles are a good indicator of a healthy hip and an active lifestyle as they have a fundamental role in walking. The automated measurement of the abductors' FF requires the challenging task of segmenting them. We aimed to design, develop and evaluate a multi-atlas based method for automated measurement of fat fraction in the main hip abductor muscles: gluteus maximus (GMAX), gluteus medius (GMED), gluteus minimus (GMIN) and tensor fasciae latae (TFL). METHOD: We collected and manually segmented Dixon MR images of 10 healthy individuals and 7 patients who underwent MRI for hip problems. Twelve of them were selected to build an atlas library used to implement the automated multi-atlas segmentation method. We compared the FF in the hip abductor muscles for the automated and manual segmentations for both healthy and patients groups. Measures of average and spread were reported for FF for both methods. We used the root mean square error (RMSE) to quantify the method accuracy. A linear regression model was used to explain the relationship between FF for automated and manual segmentations. RESULTS: The automated median (IQR) FF was 20.0(16.0-26.4) %, 14.3(10.9-16.5) %, 15.5(13.9-18.6) % and 16.2(13.5-25.6) % for GMAX, GMED, GMIN and TFL respectively, with a FF RMSE of 1.6%, 0.8%, 2.1%, 2.7%. A strong linear correlation (R2 = 0.93, p < .001, m = 0.99) was found between the FF from automated and manual segmentations. The mean FF was higher in patients than in healthy subjects. CONCLUSION: The automated measurement of FF of hip abductor muscles from Dixon MRI had good agreement with FF measurements from manually segmented images. The method was accurate for both healthy and patients groups.

Sport injuries in the paediatric and adolescent patient: a growing problem.

With an increasing number of paediatric and adolescent athletes presenting with injuries due to overuse, a greater demand is put on clinicians and radiologists to assess the specific type of injury. Repetitive forces applied to the immature skeleton cause a different type of injury than those seen in adults due to the differences in vulnerability of the musculoskeletal system, especially at the site of the growth cartilage. Intrinsic and extrinsic risk factors all play a role in the development of overuse injuries. MRI plays a key role in imaging overuse injuries due to its high potential for depicting cartilaginous and soft-tissue structures. Sport-specific biomechanics are described, since this knowledge is essential for adequate MRI assessment. An overview of several sport-related injuries is presented, based on anatomical location.

Type II autosomal dominant osteopetrosis: radiological features in two families containing five members with asymptomatic and uncomplicated disease.

In this study we analysed the imaging patterns in two families containing five members with asymptomatic and uncomplicated autosomal dominant osteopetrosis (ADO II), and we report new and uncommon radiological manifestations. These findings might be useful in the context of reducing the incidence of fractures and other orthopaedic complications. Diffuse pelvic sclerosis on radiographs was observed incidentally in two patients. Both cases were asymptomatic, and the patients had never suffered a fracture. The suggestion of ADO II was raised. A detailed medical history, an imaging survey, and a haematological study were obtained so that other rare causes of osteosclerosis could be ruled out. No genetic study was conducted. All their first-degree relatives were also examined. Bony sclerosis was observed in five patients, and the radiological findings were analysed. A not previously reported thickening of the skull base without cranial nerve palsy or optic nerve atrophy was revealed in all patients. Scoliosis was present in three of them. This has been reported previously only once in ADO II. No lower limb deformity was detected. This study provided information on the pattern of radiological features in familial asymptomatic ADO II. These data on new and rare imaging findings will increase the diagnostic awareness of physicians and will guide a thorough investigation of the entire family. This might result in a consequent decrease in the incidence of fractures and other orthopaedic complications.