Monostotic fibrous dysplasia of the spine: report of a case involving the lumbar transverse process and review of the literature

Monostotic fibrous dysplasia of the spine is rare. We report its clinical, radiologic and histologic features affecting a 47-year-old housewife. She presented with low-back pain of 1-year's duration, and radiographs showed a diffuse expansile lesion in the left transverse process of the fourth lumbar vertebra. The lesion was excised and histologically confirmed to be fibrous dysplasia. The patient remained well 8 years after operation. Including the present case, a total of 22 cases of monostotic fibrous dysplasia of the spine were found in the literature. Combining these reported cases, we found that the condition affects either sex with equal frequency and presents at any age, the mean being 32 years. There is no predilection for any part of the spinal column, though sacral or coccygeal involvement is distinctly rare. It most commonly involves the body and adjacent pedicle, although no part of the vertebra is spared. It is worth noting that a propensity for progressive enlargement, even to the extent of causing graft destruction, exists if the lesion is left untreated or incompletely treated. Complete removal of all involved bone, together with stabilization, should therefore be the treatment of choice for this condition.

Gene expression of vascular endothelial growth factor in giant cell tumors of bone

The production of vascular endothelial growth factors (VEGF), a major cause of neoangiogenesis, is a prerequisite for tumor growth and invasion. VEGF have also been shown to be important for the formation of osteoclasts. Because giant cell tumors of bone (GCT) are frequently hypervascular and have the ability to recruit macrophages and multinucleated osteoclast-like giant cells, we evaluated the levels of VEGF gene transcript in several of these tumors using Northern blot analyses, semiquantitative reverse transcription polymerase chain reaction (RT-PCR), fluorescence in situ hybridization (FISH), and immunohistochemistry. Our results showed that three major isoforms of VEGF (121, 165, and 189) were expressed in all cases of GCT investigated, with isoform 121 transcripts the most abundant. By both FISH and immunohistochemistry, we have shown that VEGF was present in spindle-shaped stromal-like tumor cells, round macrophage-like cells, and osteoclast-like multinucleate giant cells. Moreover, we have shown that the levels of VEGF gene expression but not microvessel density correlated with Enneking's clinical stage of GCT. There were higher levels of VEGF gene expression in stage III GCT than in stage I/II GCT (P < .0357). In conclusion, our results indicate that overexpression of VEGF may be associated with the advanced stage of the neoplasm.

Repair of muscle and musculotendinous junction injuries with an autogenous fascial patch

We have used an autogenous fascia lata patch to repair muscle and musculotendinous junction injuries affecting 99 individual muscles in 23 patients with multiple incised wounds to the upper limbs. All patients were followed up for at least 2 years. Two patients with severe dystrophic changes following nerve injuries were excluded from the final analysis. Satisfactory grip strength was restored 6 months following the repair in 19 of the 21 patients we evaluated. Complete active and passive range of wrist and digital motion was seen in 18 of these 21 patients. Tightness of the flexor pollicis longus was seen in 2 patients, one of whom had a deformity of the interphalangeal joint of the thumb that was passively stretched and subsequently reduced. Scar adhesions were noted in 4 other patients, but this did not affect wrist or finger motion, except in one. The autogenous fascial patch repair technique provides strong and good apposition of muscle fibres simply by distributing the force and tension over a large area of the muscle, thereby allowing early mobilization and functional restoration of the extremity.

Vascularised bone grafting for fibrous dysplasia of the upper limb

We describe our experience with vascularised bone grafting for the treatment of fibrous dysplasia of the upper limb in eight patients, five men and three women, aged between 17 and 36 years. The site was in the humerus in six and the radius in two. Persistent pain, progression of the lesion and pathological fracture with delayed union were the indications for surgical intervention.

We used a vascularised fibular graft after curettage of the lesion. Function and radiological progress were serially monitored. Early radiological union of the graft occurred at periods ranging from 8 to 14 weeks. The mean period for reconstitution of the diameter of the bone was 14 months (12 to 18) predominantly through inductive formation of bone around the vascularised graft, which was a prominent feature in all patients. There were no recurrences and none of the grafts sustained a fracture or failed to unite. After operation function was excellent in three patients and good in five. Vascularised bone grafts provide a safe and reliable means of ensuring good continuity of bone with little risk of recurrence and failure.

Vascularised bone grafting for fibrous dysplasia of the upper limb

We describe our experience with vascularised bone grafting for the treatment of fibrous dysplasia of the upper limb in eight patients, five men and three women, aged between 17 and 36 years. The site was in the humerus in six and the radius in two. Persistent pain, progression of the lesion and pathological fracture with delayed union were the indications for surgical intervention. We used a vascularised fibular graft after curettage of the lesion. Function and radiological progress were serially monitored. Early radiological union of the graft occurred at periods ranging from 8 to 14 weeks. The mean period for reconstitution of the diameter of the bone was 14 months (12 to 18) predominantly through inductive formation of bone around the vascularised graft, which was a prominent feature in all patients. There were no recurrences and none of the grafts sustained a fracture or failed to unite. After operation function was excellent in three patients and good in five. Vascularised bone grafts provide a safe and reliable means of ensuring good continuity of bone with little risk of recurrence and failure.

Imaging following allograft reconstruction in children with malignant bone tumours

PURPOSE

To determine the nature of the imaging findings following reconstructive surgery using massive allografts in children with malignant bone tumours.

MATERIALS AND METHODS

A retrospective review of the imaging studies and medical charts of 25 consecutive children who received an allograft as part of the management of a malignant bone tumour.

RESULTS

Uncomplicated allografts were sclerotic relative to native bone on radiographs and showed a typical 'tramline' appearance on bone scintigraphy. On MR, the medullary canal of the allograft showed low signal, similar to or greater than skeletal muscle, but less than subcutaneous fat, on 91 % of T1-weighted images. On short-tau inversion recovery images, the medullary canal was inhomogeneous and hyperintense to subcutaneous fat in 70 % and hyperintense to muscle in the remainder. Complications occurred in 68 % of patients and included allograft fractures (36 %), recurrent tumour (20 %), infection (8 %), and non-union or delayed union (8 %). The radiographic findings alone permitted accurate diagnosis of most serious complications. Infection and rejection were difficult to distinguish with any technique. All complications were suspected on clinical and/or radiological grounds before being shown by MR or scintigraphy.

CONCLUSIONS

Allografts, whether normal or complicated, have characteristic imaging findings, except that infection and bone resorption related to rejection and revascularisation are difficult to distinguish. Routine MR and bone scintigraphy appear to contribute little to the management of these patients.

Classifying the location of osteosarcoma with reference to the epiphyseal plate helps determine the optimal skeletal resection in limb salvage procedures

Between 1989 and 1996, 21 skeletally immature patients were treated for osteosarcoma of the extremity. Their average age was 12.6 years (range 9-16 years). We classified the location and extent of the lesion in bone on magnetic resonance imaging (MRI) with reference to the growth plate and joint margin into five subtypes. This classification served as a guide for the level of resection and the type of reconstruction required for a limb salvage procedure. All patients received neoadjuvant chemotherapy using a modified T10 protocol before the definitive operation. These patients were followed up for periods ranging from 11-86 months, with a mean of 35. 5 months. Patients were assessed for (1) local tumour recurrence, (2) metastatic disease, (3) allograft complications and (4) extremity function and joint stability. Excellent function was retained in 2, good in 13 and fair function in 6 patients. The MRI classification proved useful for the resection and provides an insight into the possible functional outcomes.

Chronic recurrent multifocal osteomyelitis: a great clinical and radiologic mimic in need of recognition by the pathologist

The spectrum of histopathologic changes in four cases of chronic recurrent multifocal osteomyelitis encountered in our orthopedic outpatient clinic in the past 3 years was studied in conjunction with clinical and radiologic findings. All presented with pain with or without swelling in the affected region. Radiographically, the appearance of the lesions varied from a mixed picture of bone lysis and sclerosis with expansion to sclerosis alone to bone collapse. Bone scintigraphy demonstrated asymptomatic and separate foci of activity in all cases. Prior to biopsy, the clinical and radiologic differential diagnoses included Ewing's sarcoma, metastatic neuroblastoma, hematolymphoid malignancy, Langerhans cell histiocytosis and chronic infection, notably tuberculosis. The spectrum of histopathologic changes ranged from acute (acute inflammatory infiltration, active bone resorption and necrosis, reactive bone formation) to subacute (predominantly lymphocytic and plasma cell infiltration) to chronic inflammation (fibroblastic organization and bony sclerosis). Histologic changes correlated poorly with clinical features, but relatively well with radiologic findings. Lesional excision was performed in one case, cortical saucerization in another, while the final two cases received supportive treatment. All remained well 18-21 months post-therapy. Chronic recurrent multifocal osteomyelitis is a great clinical and radiologic mimic, which merits recognition by the pathologist. Awareness of the spectrum of histologic features encountered enables a correct diagnosis to be made in the appropriate clinical setting. The patient can thus be reassured of a favorable prognosis.

A technique for enhancing union of allograft to host bone

The aim of limb-salvage surgery in malignant bone tumours in children is to restore function and eradicate local disease with as little morbidity as possible. Allografts are associated with a high rate of complications, particularly malunion at the allograft-host junction. We describe a simple technique which enhances union of allograft to host bone taking advantage of the discrepancy in size between the adult allograft and the child's bone. This involves lifting a flap of periosteum before resection from the host bone, which is then telescoped into the allograft medullary canal, which may require internal burring or splitting, for a distance of 1.5 to 2 cm and covering the bone junction with the periosteal flap. This is more stable than conventional end-to-end opposition. For each centimetre of telescoping the surface area available for bony union is increased more than three times. The periosteal flap also augments union. Additional surface fixation with a plate and screws is not necessary. We have used this technique in nine children, in eight of whom there was complete union at a mean of 16 weeks. Delayed union, associated with generalised limb osteoporosis, occurred in one. Early mobilisation, with weight-bearing by three weeks, was possible. There was only one fracture of the allograft.

A technique for enhancing union of allograft to host bone

The aim of limb-salvage surgery in malignant bone tumours in children is to restore function and eradicate local disease with as little morbidity as possible. Allografts are associated with a high rate of complications, particularly malunion at the allograft-host junction. We describe a simple technique which enhances union of allograft to host bone taking advantage of the discrepancy in size between the adult allograft and the child’s bone. This involves lifting a flap of periosteum before resection from the host bone, which is then telescoped into the allograft medullary canal, which may require internal burring or splitting, for a distance of 1.5 to 2 cm and covering the bone junction with the periosteal flap. This is more stable than conventional end-to-end opposition. For each centimetre of telescoping the surface area available for bony union is increased more than three times. The periosteal flap also augments union. Additional surface fixation with a plate and screws is not necessary.

We have used this technique in nine children, in eight of whom there was complete union at a mean of 16 weeks. Delayed union, associated with generalised limb osteoporosis, occurred in one. Early mobilisation, with weight-bearing by three weeks, was possible. There was only one fracture of the allograft.

Primary juxtacortical chondrosarcoma dedifferentiating after 20 years

We present the clinical, radiographic and pathological features of a juxtacortical chondrosarcoma which underwent dedifferentiation to an osteosarcoma in a 47-year-old woman. The tumour, abutting the femoral diaphysis, had initially presented 20 years earlier. Local excision was performed at presentation and again 10 years later, but the tumour recurred on each occasion. Serial radiographs showed cortical saucerisation evolving to cortical buttressing and mounding. After 20 years a dramatic radiographic change heralded tumour dedifferentiation.

Assessment of chemosensitivity in patients with osteogenic sarcoma using the doxorubicin binding assay

BACKGROUND AND OBJECTIVES

Assessment of chemosensitivity in patients with osteosarcoma may help identify those with resistance to chemotherapy. In this study, we investigated the clinical value of the doxorubicin binding assay in its ability to identify patients with drug resistance.

METHODS

We tested tumor tissue samples obtained at biopsy of 24 patients with high-grade osteosarcoma aged 9-61 years (mean 19.2) for sensitivity to doxorubicin, using the doxorubicin binding assay. Tumor excision was performed in these patients after neoadjuvant chemotherapy. Chemotherapy response was judged on the basis of tumor necrosis achieved and was compared with doxorubicin sensitivity in each of these patients.

RESULTS

Doxorubicin sensitivity was good in 15 and poor in 9 of 24 patients studied. In patients with good sensitivity (n = 15), 9 (60%) exhibited a good response to chemotherapy while response was poor in 6. In patients with poor sensitivity (n = 9), response to chemotherapy was poor in all 9 (100%) patients and 7 (77.8%) of these patients developed metastatic disease within a mean period of 5.2 months, resulting in two deaths. The results were statistically significant at P = 0.0193.

CONCLUSIONS

Doxorubicin binding assay may be useful in identifying patients with inherent resistance to chemotherapy. As the outcome of patients showing resistance to doxorubicin is poor, innovative strategies may need to be developed for this group of patients.

Angiomatoid malignant fibrous histiocytoma: report of an unusual case with highly aggressive clinical course

The authors report a case of angiomatoid malignant fibrous histiocytoma (AMFH), affecting a 9-year-old girl, with a highly aggressive clinical course. The tumor, noticed by the patient as a painless nodule in the dorsum of her left foot for 12 months, recurred 8 months after initial excision, and despite wide local reexcision, metastasized 4 months later to the liver and lung, where it grew at an alarming rate, to the extent of occupying the entire left hemithorax in a period of 10 weeks and killed the patient 14 months after initial excision. Review of the literature showed that the culminated rates of recurrence, metastasis, and mortality for AMFH were 23.2%, 8.7%, and 4.3%, respectively, indicating that it is definitely a malignant neoplasm with a potentially fatal outcome.

Vascularized bone grafts in the treatment of juxta-articular giant-cell tumors of the bone

The clinical results of vascularized bone grafts in 39 patients with giant-cell tumor affecting the extremity were evaluated. The sites involved were the proximal tibia (8), proximal femur (4), calcaneus (1), proximal humerus (8), and distal radius (18). Osteoarticular replacement was performed in patients with giant-cell tumor involving the radius; in 15 of these, a suitably tailored vascularized iliac crest graft was used, and in the remaining three, the fibula was used. Follow-up ranged from 2 to 7 years, with an average of 3.3 years. Clinical results were judged on the basis of functional and radiologic evaluations. Reconstructions involving the distal radius were evaluated separately from the rest of the juxta-articular grafts. Excellent results in 17 and good results in three of the juxta-articular grafts were observed. Eighteen patients with the distal radius affected were followed-up for periods ranging from 2 to 12 years. Non-union was seen in one, carpal subluxation in five, and spontaneous radiocarpal fusion in one patient. A pain-free functional wrist was retained in 17 of these 18 patients. Three local recurrences were observed (2.5 percent). The vascularized bone graft provided a good biological and mechanical support to the subchondral bone and overlying articular cartilage. Satisfactory reconstruction was thus possible following wide resection, without sacrificing joint function and with gratifying oncologic results. The use of a suitably tailored block of vascularized iliac crest is an acceptable method to preserve wrist and radio-ulnar joint motion, following excision of the distal radius affected by a giant-cell neoplasm.

Intracortical osteosarcoma

Intracortical osteosarcomas originate in the bone cortex and represent the rarest type of osteosarcoma. We describe the clinical, radiological and histological features of an intracortical osteosarcoma occurring in the femur of a young man and discuss the pertinent features of this tumour compared to those previously reported.

Extra-articular pigmented villonodular synovitis of the temporomandibular joint

Pigmented villonodular synovitis, a benign but locally destructive fibrohistiocytic proliferative lesion involving tendon sheaths, bursae and diarthrodial joints, is distinctly rare in the temporomandibular joint. We report one such case occurring in a 42-year-old housewife who presented with a progressively enlarging right zygomatic mass for six months. On exploration, an orange-brown firm mass, 5 x 3 x 2 cm, was seen adherent to the lateral aspect of the capsule of the right temporomandibular joint, and eroding into the inferior aspect of the right temporal bone and part of the mandibular condyle. The mass was completely excised. Pathological examination showed features typical of those of pigmented villonodular synovitis and the lesion was entirely extra-articular in location. The patient remained well with no evidence of local recurrence two years after operation. Review of the literature and careful analysis of the clinicopathological features showed that the vast majority of the reported cases of pigmented villonodular synovitis of the temporomandibular joint belonged to the extra-articular variant, which is associated with a more aggressive local infiltrative behaviour and higher rate of local recurrence than the localized type. The recommended treatment for this condition is therefore wide local excision, aiming to remove the lesion as completely as possible without producing severe disability for the patient.

Stabilization of osteochondral fractures: an experimental study comparing polyglycollic acid degradable pin with K-wire stabilization in rabbits

Conventional metal implants may be unsuitable for the stabilization of osteochondral fractures as they may interfere with joint function and eventually require implant removal. We therefore compared the use of biodegradable implants with conventional metal ones in an animal experimental study conducted in skeletally mature rabbits. Biodegradable polyglycollic acids pins (PGA) 1.5 mm in diameter were used to stabilize an osteochondral fragment surgically created in the distal femur of rabbits. In another group of 36 animals, conventional metal K-wire of the same diameter was used for stabilization. The animals were killed at intervals of 3 to 24 weeks. Satisfactory union of the fragments was noted in 92% of the PGA implants as compared with 50% with the metal implants group. No implant migration was seen in the PGA group, while migration was noted in all animals with the metal implants. Histological studies showed that in 80% of the cases fixed with PGA implants, the fragment was viable. In the metal group 33% of the fragments underwent fragmentation and necrosis.

Bacterial colonization of bone allografts related to increased interval between death and procurement: an experimental study in rats

Whereas organs from donors must be removed almost immediately after death to maximize organ viability in the recipient, there is a slightly longer window for tissue allograft recovery. To determine the maximum safe interval after death within which bone allografts may be harvested for clinical use, an experimental model was devised using adult Sprague-Dawley (SD) rats and duplicating cadaveric storage techniques. Allografts were procured at increasing time intervals after death. The grafts were then transplanted to 80 living SD rats, and the animals killed at 7 weeks to evaluate any increase in the risk of infection and bacterial colonization. None of the allografts procured within 48 h after death were colonized with bacteria, while 12% of grafts procured at 96 h and 50% of allografts procured at 1 week were colonized. The results suggest that it may be possible to extend the safe period within which cadaveric tissue may be procured for transplantation to up to 96 h following death, provided scrupulous measures to prevent and detect microorganism contamination are followed.

Clinics in diagnostic imaging (25). Aggressive vertebral haemangioma

A 30-year-old female presented with a three month history of back pain. Radiographs and computed tomography indicated an aggressive haemangioma of T12 which was confirmed on red cell scintigraphy. The varying imaging appearances of non-aggressive and aggressive vertebral haemangiomas are described, emphasizing the ability of aggressive haemangiomas to mimic metastases on magnetic resonance imaging. The therapeutic role of embolisation as an adjunct ro surgery is stressed.

Revascularization of the testis following inadvertent division of the testicular vessels during hernia repair

This case report describes the revascularization of the testis in a 21-year-old man after his testicular vessels were inadvertently divided during primary repair of an inguinal hernia. The circumstances in which this occurred and the possible complications are discussed and the need to attempt repair of the divided vessels in such cases is emphasized.

Resurfacing of thumb-pulp loss with a heterodigital neurovascular island flap using a nerve disconnection/reconnection technique

The problems of late deterioration of sensation and a "double sensibility" phenomenon, either in the thumb or donor finger, are a known deficiency of the conventional heterodigital neurovascular island flap. This is probably related to unsatisfactory cortical reorientation following flap transfer. To obviate this problem, the authors have used a disconnection/reconnection technique for heterodigital island flaps in 17 patients, to resurface defects in the skin of the thumb. All patients were followed-up for 1 year, while 15 were followed-up for 2 years or more. There were no flap complications or failures, and the length of the thumb tip was preserved in all cases. The classic two-point discrimination was less than 6 mm in eight of these patients, and the remaining nine patients had two-point discrimination of between 6 and 8 mm. This technique was found to provide sensitive, supple, and well-vascularized skin with proper cortical representation, to replace the loss of the tactile pump of the thumb tip in one operative stage.