Radiographic morphology of normal ring apophyses in the immature cervical spine.

BACKGROUND: The ring apophyses of the cervical spine have a variable appearance that changes with age. The times at which they appear and fuse at each level are not fixed. In this study, we aim to detail normal ranges of appearance of these ossification centers for each age group. MATERIALS AND METHODS: One hundred and eighty patients under the age of 21 attending the Royal Stoke University Hospital for cervical spine radiographs were retrospectively identified. The presence or absence of ring apophyses at each cervical level and whether these had undergone fusion was reported, as were the thickness, length, and craniocaudal and anteroposterior distance of the apophysis from the vertebral body. The angulation of the apophysis relative to the endplate was also noted. RESULTS: The youngest patient in which apophyses were seen was aged 3, but apophyses were otherwise rarely seen before the age of 6. All apophyses were present from age 14, and the superior apophyses fused by the age of 18, although unfused inferior apophyses were still seen in the 20-year age group. It was observed that apophyses were rarely separated from the vertebral body by greater than 1 mm in craniocaudal distance (1%) or 2.5 mm in anteroposterior distance (2.6%) and the anterior apophysis was angulated towards the endplate in only 1% of cases. CONCLUSIONS: We have detailed the range of normal appearances of the ring apophyses of the developing cervical spine. Cervical spine apophyseal injury is thought to be rare, but knowledge of normative morphological features should help in this diagnosis.

Complete resolution and remodeling of chronic recurrent multifocal osteomyelitis on MRI and radiographs.

Chronic recurrent multifocal osteomyelitis (CRMO) is a rare condition thought to be under-diagnosed, with a true prevalence of more than the 1 in 10,000 estimated. It is a condition that is classically described as polyostotic with a relapsing and remitting course, preferentially affecting the metaphyses of tubular bones in the pediatric population. Lesions have characteristic appearances of cortical hyperostosis and mixed lytic/sclerotic medullary appearances radiographically, with active osteitis and periostitis best seen with fluid-sensitive sequences on magnetic resonance imaging (MRI). There are reports of lesions resolving on follow-up radiographs and MRI scans, but no supporting images. In particular, although the marrow appearances and degree of osteitis have been shown to improve on MRI, complete resolution and remodeling back to normal has never been demonstrated. We present a case of a lesion that has completely healed and remodeled back to normal appearances on both radiographs and MRI, and consider this the standard for the often loosely used terms "normalization" and "resolution". We discuss the implications of this for our understanding of the natural history of CRMO, and how this adds weight to the condition being significantly under-diagnosed. It provides a "gold standard" to be aimed for when assessing treatments for CRMO, and the optimal outcomes that are possible. It also provides further insight into the potential of pediatric bone to recover and remodel when affected by inflammatory conditions.

A new method for measurement of subcoracoid outlet and its relationship to rotator cuff pathology at MR arthrography.

OBJECTIVE: Orthopaedic surgical studies have shown that variations in the vertical distance between the tip of the coracoid process and the supra-glenoid tubercle alter the shape of the subcoracoid outlet. Our objective was to measure the vertical distance between the coracoid tip and the supra-glenoid tubercle (CTGT) on MR and to assess whether this showed better correlation with rotator cuff pathology compared with the axial coraco-humeral distance. MATERIALS AND METHODS: A retrospective review was performed of 100 consecutive shoulder MR arthrograms. Vertical distance between the coracoid tip and the supraglenoid tubercle was measured in the sagittal oblique plane. Separate assessment was then made of tendon pathology of the subscapularis, supraspinatus and long head of biceps tendons. Axial coraco-humeral distance was then measured. Correlation between tendon abnormalities and the two measurements was then made. RESULTS: Of the 100 cases, 42 had subscapularis tendon lesions, 21 had lesions of the long head of biceps and 53 had supraspinatus tendon lesions. Mean vertical distance from the coracoid tip to supraglenoid tubercle was greater in those with lesions of any of these tendons and was statistically significant for the supraspinatus group (P = 0.005). Reduced axial coraco-humeral distance was also seen in patients with tendinopathy, although with less statistically significant difference (p = 0.059). CONCLUSION: Our results support orthopaedic studies that have shown that the vertical distance between the coracoid tip and the supraglenoid tubercle increases the incidence and risk of rotator cuff disease by altering the shape of the subcoracoid outlet.

MRI of inflammatory spondyloarthropathy following traumatic cauda equina syndrome.

BACKGROUND CONTEXT: Spondyloarthropathy has been described radiographically in patients following paralysis from spinal cord trauma. Onset of these findings after cauda equina syndrome have not been reported previously. Furthermore, the magnetic resonance documentation of its early evolution has not been recorded. PURPOSE: We report a case of early-onset spondyloarthropathy shown by magnetic resonance imaging (MRI) in a patient with cauda equina syndrome due to bilateral sacral insufficiency fractures. STUDY DESIGN: Unique case study review, one case. METHODS: Review of the clinical case notes and imaging including initial and subsequent MR imaging. RESULTS: The initial MRI of the lumbosacral spine showed bilateral sacral insufficiency fractures with a kyphotic deformity. The vertebral bodies were normal on the initial computed tomography and MRI studies, which did not reveal pre-existing features of sacroiliitis. The second MRI performed 5 months later clearly showed spondylitis at multiple vertebral levels with partial resolution 18 months post injury. CONCLUSION: Spondyloarthropathy in patients with paralysis due to spinal cord injury is well documented in the English language literature, but until now this has not been demonstrated by MRI. It is a rare complication of traumatic cauda equina syndrome that commences soon after the traumatic event and can resolve spontaneously.

Subcutaneous and lung metastases from chondrosarcoma of the thumb.

We present a rare case of metacarpal chondrosarcoma with cutaneous metastases in the ipsilateral upper arm. Chondrosarcomas of the small bones of the hand rarely metastasise unlike chondrosarcomas elsewhere in the body. Excision/ray amputation rather than curettage may be preferable in the treatment of high-grade chondrosarcomas in the hand.

Intra-epiphyseal stress injury of the proximal tibial epiphysis: preliminary experience of magnetic resonance imaging findings.

Stress induced injuries affecting the physeal plate or cortical bone in children and adolescents, especially young athletes, have been well described. However, there are no reports in the current English language literature of stress injury affecting the incompletely ossified epiphyseal cartilage. We present four cases of stress related change to the proximal tibial epiphysis (PTE) along with their respective magnetic resonance imaging (MRI) appearances ranging from subtle oedema signal to a pseudo-tumour like appearance within the epiphyseal cartilage. The site and pattern of intra-epiphyseal injury is determined by the type of tissue that is affected, the maturity of the skeleton and the type of forces that are transmitted through the tissue. We demonstrate how an awareness of the morphological spectrum of MRI appearances in intra-epiphyseal stress injury and the ability to identify concomitant signs of stress in other nearby structures can help reduce misdiagnosis, avoid invasive diagnostic procedures like bone biopsy and reassure patients and their families.

Adiposis dolorosa (Dercum's disease): MRI and ultrasound appearances.

AIM: To describe ultrasound and magnetic resonance imaging (MRI) features of adiposis dolorosa, Dercum's disease, and to evaluate the MRI features prospectively against a large number of MRI examinations. MATERIALS AND METHODS: Institutional review board approval for this study was obtained. The imaging features at MRI and ultrasound of 13 cases of adiposis dolorosa (nine female, four male; age range 32-72 years) were reviewed. MRI findings typical for adiposis dolorosa were proposed and prospectively evaluated on 6247 MRI examinations performed over a period of 8 months. RESULTS: Adiposis dolorosa demonstrates multiple, oblong, fatty lesions in the superficial subcutaneous fatty tissue. They are mostly <2 cm in long axis diameter. They demonstrate nodular ("blush-like") increased fluid signal at unenhanced MRI and are markedly hyperechoic at ultrasound. There is no contrast medium enhancement at MRI and no increased Doppler signal at ultrasound. Most lesions were clinically asymptomatic, some were painful/tender. There was no imaging evidence of oedema or inflammation. During prospective validation of these MRI features on 6247 MRI examinations, two cases with typical imaging features were encountered; both were diagnosed as adiposis dolorosa on clinical review. All cases of adiposis dolorosa showed these imaging findings. This results in a very low likelihood that a nodular, blush-like appearance of subcutaneous fat on MRI is not due to adiposis dolorosa. DISCUSSION: Adiposis dolorosa, Dercum's disease, should be suggested in the presence of multiple (many) small, oblong, fatty lesions in the subcutaneous fatty tissue in adult patients if they are hyperechoic on ultrasound imaging or blush-like at unenhanced MRI; typically a small number of these lesions are tender/painful. Imaging does not demonstrate inflammation or oedema in relation to these lesions. These MRI features should suggest the diagnosis and are likely to be pathognomonic. The radiologist is often the first to suggest the diagnosis based on the imaging features.

Destructive discovertebral degenerative disease of the lumbar spine.

The uncommon variant of degenerative hip joint disease, termed rapidly progressive osteoarthritis, and highlighted by severe joint space loss and osteochondral disintegration, is well established. We present a similar unusual subset in the lumbar spine termed destructive discovertebral degenerative disease (DDDD) with radiological features of vertebral malalignment, severe disc resorption, and "bone sand" formation secondary to vertebral fragmentation. Co-existing metabolic bone disease is likely to promote the development of DDDD of the lumbar spine, which presents with back pain and sciatica due to nerve root compression by the "bone sand" in the epidural space. MRI and CT play a complimentary role in making the diagnosis.

Role of MRI in hip fractures, including stress fractures, occult fractures, avulsion fractures.

MR imaging plays a vital role in the diagnosis and management of hip fractures in all age groups, in a large spectrum of patient groups spanning the elderly and sporting population. It allows a confident exclusion of fracture, differentiation of bony from soft tissue injury and an early confident detection of fractures. There is a spectrum of MR findings which in part is dictated by the type and cause of the fracture which the radiologist needs to be familiar with. Judicious but prompt utilisation of MR in patients with suspected hip fractures has a positive therapeutic impact with healthcare cost benefits as well as social care benefits.

SAPHO: What radiologists should know.

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) is an umbrella acronym for inflammatory clinical conditions whose common denominator is aseptic osteoarticular involvement with characteristic skin lesions. It involves all ages, can involve any skeletal site, and has variable imaging appearances depending on the stage/age of the lesion and imaging method. It mimics important differentials including infection and neoplasia. Awareness of the imaging features, especially in the spine, facilitates early diagnosis, prevents repeated biopsies, and avoids unnecessary surgery, while initiating appropriate treatment.

Successful treatment of refractory tibial nonunion using calcium sulphate and bone marrow stromal cell implantation.

Successful healing of a nine-year tibial nonunion resistant to six previous surgical procedures was achieved by tissue engineering. We used autologous bone marrow stromal cells (BMSCs) expanded to 5 x 10(6) cells after three weeks' tissue culture. Calcium sulphate (CaSO4) in pellet form was combined with these cells at operation. The nonunion was clinically and radiologically healed two months after implantation. This is the description of on healing of a long-standing tibial nonunion by tissue engineering. The successful combination of BMSCs and CaSO4 has not to our knowledge been reported in a clinical setting.

Observations on the natural history of massive lumbar disc herniation.

We have treated 15 patients with massive lumbar disc herniations non-operatively. Repeat MR scanning after a mean 24 months (5 to 56) showed a dramatic resolution of the herniation in 14 patients. No patient developed a cauda equina syndrome. We suggest that this condition may be more benign than previously thought.

The spine in Paget's disease.

Paget's disease (PD) is a chronic metabolically active bone disease, characterized by a disturbance in bone modelling and remodelling due to an increase in osteoblastic and osteoclastic activity. The vertebra is the second most commonly affected site. This article reviews the various spinal pathomechanisms and osseous dynamics involved in producing the varied imaging appearances and their clinical relevance. Advanced imaging of osseous, articular and bone marrow manifestations of PD in all the vertebral components are presented. Pagetic changes often result in clinical symptoms including back pain, spinal stenosis and neural dysfunction. Various pathological complications due to PD involvement result in these clinical symptoms. Recognition of the imaging manifestations of spinal PD and the potential complications that cause the clinical symptoms enables accurate assessment of patients prior to appropriate management.

Cauda equina syndrome presentation of sacral insufficiency fractures.

INTRODUCTION: Sacral insufficiency fractures are a well recognised cause for low back, buttock and groin pain in the elderly. However, over a 4 year period, four patients have presented with symptoms of cauda equina syndrome, who were found on investigation to have acute sacral insufficiency fracture without any other aetiological spinal abnormality. PATIENTS AND METHOD: Four patients who presented to the spinal surgeons of our institution with symptoms of cauda equina syndrome were referred for spinal MR. Sagittal and axial T1 and T2 weighted turbo spin echo sequences of the lower thoracic and lumbar spine were performed on all patients. Subsequent studies included MR of the sacrum supplemented where appropriate by CT and technetium MDP bone scintigraphy. RESULTS: No evidence of a compressive lesion of the lower thoracic or lumbar spine was present in any of the four patients. Dedicated MR examination of the sacrum in these patients revealed unilateral acute insufficiency fractures involving zone 1 from S1 to S3 extending from the sacro-iliac joint to the lateral margin of the sacral foramen. There was no evidence of compression of the sacral nerve roots. The possible mechanism for the symptomatic presentation is discussed. CONCLUSION: Sacral insufficiency fractures should be excluded in elderly or osteoporotic patients presenting with cauda equina syndrome who have no evidence of compression in the thoraco-lumbar MR studies.

Coccygectomy for coccydynia: case series and review of literature.

STUDY DESIGN: This is a case series in which case notes review and telephone interview update were used to assess the outcome following coccygectomy. OBJECTIVE: To correlate the clinical results of coccygectomy with histology and discography of the sacrococcygeal and intercoccygeal segments. SUMMARY OF BACKGROUND DATA: Clinicians regard chronic disabling pain in the sacrococcygeal region with much dismay because of the reputed unpredictability of the treatment outcome. METHODS: A total of 38 patients had coccygectomy for intractable coccydynia, and 31 were available for follow-up. The excised specimen with intact sacrococcygeal joint was sent for histologic examination in 22 patients. There were 6 patients investigated using sacrococcygeal and intercoccygeal discography. RESULTS: Mean postoperative follow-up was 6.75 years (range 2-16). There were 16 patients who benefited highly from the surgery, and 6 benefited to some extent, giving an overall beneficial result of 71%. Of all specimens, 86.3% had histologic changes of degeneration. Moderate-to-severe degenerate changes in sacrococcygeal and intercoccygeal joints on histology were found in 54.5% of patients. Of these patients, 83.3% did well with surgery. Only 57.1% of those patients with mild changes did well. There were 2 patients who had positive discography, and both did well with surgery. Three patients had negative diskographies, and 2 of them had a poor result, and 1 had only some relief. CONCLUSIONS: It is possible that degenerate changes in sacrococcygeal discs and/or intercoccygeal discs are associated with pain. Surgical results are better in those with a severe degree of degenerative change. Coccygectomy remains a successful treatment for a majority of severely disabled patients with coccydynia.

Primary synovial osteochondromatosis presenting as constrictive capsulitis.

Primary synovial chondromatosis of the joints can present as capsular constriction with peri-articular osteopenia. This rare presentation is highlighted in three cases (two hips and one shoulder). The diagnosis in all the patients was made on arthrography and/or MRI/CT and was confirmed histologically. Synovial chondromatosis should be considered in patients with this presentation. Arthrography is the best imaging modality to confirm the cause (synovial chondromatosis) and effect (constrictive capsulitis).

Percutaneous radiofrequency thermocoagulation of osteoid osteomas: factors affecting therapeutic outcome.

OBJECTIVE: To examine factors which affect local recurrence of osteoid osteomas treated with percutaneous CT-guided radiofrequency thermocoagulation. DESIGN AND PATIENTS: A prospective study was carried out on 45 patients with osteoid osteoma who underwent percutaneous radiofrequency thermocoagulation with a minimum follow-up of 12 months. RESULTS: There were seven local recurrences (16%); all occurred within the first year. Local recurrence was significantly related to a non-diaphyseal location (P<0.01). There was no significant relationship (P=0.05) between local recurrence and age of the patient, duration of symptoms, previous treatment, size of the lesion, positive biopsy, radiofrequency generator used or the number of needle positions. There were no complications. CONCLUSIONS: Osteoid osteomas in a non-diaphyseal location are statistically more likely to recur than those in a diaphyseal location when treated with CT-guided percutaneous radiofrequency thermocoagulation. This relationship between local recurrence and location has not been previously reported.

Stress-induced Salter-Harris I growth plate injury of the proximal tibia: first report.

We describe a case of chronic Salter-Harris I injury of the proximal tibial epiphysis. To our knowledge such an injury has not been described in the English language literature. The radiological appearance can mimic chronic infection. The possibility of chronic athletic stress-related change should be considered in such scenarios to avoid a misdiagnosis.

Subperiosteal ganglion associated with Paget's disease of bone.

Tumoral lesions related to Paget's disease may be classified as malignant, benign or pseudotumoral. While sarcomatous degeneration is the most feared complication, awareness of benign and pseudotumoral lesions is essential for assisting in accurate histological interpretation of the biopsy sample, which may avoid unnecessary repeat biopsies. We present the first case of a juxta-articular subperiosteal ganglion associated with Paget's disease, with classic imaging characteristics, especially on CT examination. The well-defined soft tissue mass at the medial aspect of the obturator rim, adjacent to a small fracture in pagetic quadrilateral plate, showed an ossified rim and internal gas lucencies, these being the hallmarks of a juxta-articular subperiosteal ganglion. On MRI, the lesion was of intermediate signal intensity on T1-weighted sequences, increased signal intensity on T2-weighted sequences, with rim enhancement after gadolinium contrast injection and preservation of fatty marrow signal of the underlying pagetic bone. Identification of the entity avoided an unnecessary biopsy or surgical intervention.

A corrective osteotomy for post-traumatic malrotation and shortening of the femur.

Malrotation following femoral nailing is problematic. We describe a new one-stage technique which utilises three components; a cortico-periosteal sleeve, a "dialled-in"correction of rotation and a peg-shaped osteotomy. Seven patients were treated. The mean correction of malrotation was within 5 degrees of the normal side and the mean correction of length was within 8 mm of the normal side. Clinical union was achieved on average by 6 months (range 4-8 months). The only complication was locking screw breakage in one case. The cortico-periosteal sleeve avoids the need for bone graft, surgery is facilitated by the use of "dialled-in" correction of rotation and a peg to correct length.