A chordoma which occurs as a primary tumour outside the axial skeleton is known as an extra-axial chordoma, parachordoma or chordoma periphericum. It is extremely rare and therefore survival, recurrence and the rates of metastasis are not known. Whilst few recurrences have been described, the extra-axial chordoma has the potential for late recurrence at up to 12 years. Metastases are even less frequent.

We report the case of a 56-year-old woman who developed an extra-axial chordoma of the right thoracic wall in close relationship with the tenth rib. The tumour was completely removed and the prognosis is excellent.

We have treated 175 patients with a chordoma over a ten-year period. Only two had a family history of the condition and we describe these in this paper. In one patient the tumour was at the craniocervical junction and in the other the lesion affected the sacrum. We have undertaken a literature review of familial chordoma and have identified chromosomal abnormalities associated with the condition.

A total of 38 patients with leprosy and localised nerve damage (11 median at the wrist and 37 posterior tibial at the ankle) were treated by 48 freeze-thawed skeletal muscle autografts ranging between 2.5 cm and 14 cm in length. Sensory recovery was noted in 34 patients (89%) and was maintained during a mean period of follow-up of 12.6 years (4 to 14). After grafting the median nerve all patients remained free of ulcers and blisters, ten demonstrated perception of texture and eight recognised weighted pins. In the posterior tibial nerve group, 24 of 30 repairs (80%) resulted in improved healing of the ulcers and 26 (87%) demonstrated discrimination of texture. Quality of life and hand and foot questionnaires showed improvement; the activities of daily living scores improved in six of seven after operations on the hand, and in 14 of 22 after procedures on the foot. Another benefit was subjective improvement in the opposite limb, probably because of the protective effect of better function in the operated side. This study demonstrates that nerve/muscle interposition grafting in leprosy results in consistent sensory recovery and high levels of patient satisfaction. Ten of 11 patients with hand operations and 22 of 25 with procedures to the foot showed sensory recovery in at least one modality.

Implantation of autologous chondrocytes and matrix autologous chondrocytes are techniques of cartilage repair used in the young adult knee which require harvesting of healthy cartilage and which may cause iatrogenic damage to the joint. This study explores alternative sources of autologous cells.

Chondrocytes obtained from autologous bone-marrow-derived cells and those from the damaged cartilage within the lesion itself are shown to be viable alternatives to harvest-derived cells. A sufficient number and quality of cells were obtained by the new techniques and may be suitable for autologous chondrocyte and matrix autologous chondrocyte implantation.

The anatomical studies, basic to our understanding of lumbar spine innervation through the sinu-vertebral nerves, are reviewed. Research in the 1980s suggested that pain sensation was conducted in part via the sympathetic system. These sensory pathways have now been clarified using sophisticated experimental and histochemical techniques confirming a dual pattern. One route enters the adjacent dorsal root segmentally, whereas the other supply is non-segmental ascending through the paravertebral sympathetic chain with re-entry through the thoracolumbar white rami communicantes.

Sensory nerve endings in the degenerative lumbar disc penetrate deep into the disrupted nucleus pulposus, insensitive in the normal lumbar spine. Complex as well as free nerve endings would appear to contribute to pain transmission.

The nature and mechanism of discogenic pain is still speculative but there is growing evidence to support a ‘visceral pain’ hypothesis, unique in the muscloskeletal system. This mechanism is open to ‘peripheral sensitisation’ and possibly ‘central sensitisation’ as a potential cause of chronic back pain.

The most appropriate protocol for the biopsy of musculoskeletal tumours is controversial, with some authors advocating CT-guided core biopsy. At our hospital the initial biopsies of most musculoskeletal tumours has been by operative core biopsy with evaluation by frozen section which determines whether diagnostic tissue has been obtained and, if possible, gives the definitive diagnosis. In order to determine the accuracy and cost-effectiveness of this protocol we have undertaken a retrospective audit of biopsies of musculoskeletal tumours performed over a period of two years.

A total of 104 patients had biopsies according to this regime. All gave the diagnosis apart from one minor error which did not alter the management of the patient. There was no requirement for re-biopsy. This protocol was more labour-intensive and 38% more costly than CT-guided core biopsy (AU$1804 vs AU$1308). However, the accuracy and avoidance of the anxiety associated with repeat biopsy outweighed these disadvantages.

We attempted to repair full-thickness defects in the articular cartilage of the trochlear groove of the femur in 30 rabbit knee joints using allogenic cultured chondrocytes embedded in a collagen gel. The repaired tissues were examined at 2, 4, 8, 12 and 24 weeks after operation using histological and histochemical methods. The articular defect filling index measurement was derived from safranin-O stained sections. Apoptotic cellular fractions were derived from analysis of apoptosis in situ using TUNEL staining, and was confirmed using caspase-3 staining along with quantification of the total cellularity. The mean articular defect filling index decreased with time. After 24 weeks it was 0.7 (sd 0.10), which was significantly lower than the measurements obtained earlier (p < 0.01). The highest mean percentage of apoptotic cells were observed at 12 weeks, although the total cellularity decreased with time. Because apoptotic cell death may play a role in delamination after chondrocyte transplantation, anti-apoptotic gene therapy may protect transplanted chondrocytes from apoptosis.

Sex hormones play important roles in the regulation of the proliferation, maturation and death of chondrocytes in the epiphyseal growth plate. We have investigated the effects of male castration on the cell kinetics of chondrocytes as defined by the numbers of proliferating and dying cells. The growth plates of normal rabbits and animals castrated at eight weeks of age were obtained at 10, 15, 20 and 25 weeks of age.

Our study suggested that castration led to an increase in apoptosis and a decrease in the proliferation of chondrocytes in the growth plate. In addition, the number of chondrocytes in the castrated rabbits was less than that of normal animals of the same age.

Osteofibrous dysplasia is an unusual developmental condition of childhood, which almost exclusively affects the tibia. It is thought to follow a slowly progressive course and to stabilise after skeletal maturity. The possible link with adamantinoma is controversial and some authors believe that they are part of one histological process.

We retrospectively reviewed 16 patients who were diagnosed as having osteofibrous dysplasia initially or on the final histological examination. Their management was diverse, depending on the severity of symptoms and the extent of the lesion. Definitive (extraperiosteal) surgery was localised ‘shark-bite’ excision for small lesions in five patients. Extensive lesions were treated by segmental excision and fibular autograft in six patients, external fixation and bone transport in four and proximal tibial replacement in one. One patient who had a fibular autograft required further excision and bone transport for recurrence. Six initially underwent curettage and all had recurrence. There were no recurrences after localised extraperiosteal excision or bone transport. There were three confirmed cases of adamantinoma.

The relevant literature is reviewed. We recommend extraperiosteal excision in all cases of osteofibrous dysplasia, with segmental excision and reconstruction in more extensive lesions.

We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.

We have investigated in vitro the release kinetics and bioactivity of fibroblast growth factor-2 (FGF-2) released from a carrier of fibrin sealant. In order to evaluate the effects of the FGF-2 delivery mechanism on the repair of articular cartilage, full-thickness cylindrical defects, 5 mm in diameter and 4 mm in depth, which were too large to undergo spontaneous repair, were created in the femoral trochlea of rabbit knees. These defects were then filled with the sealant.

Approximately 50% of the FGF-2 was released from the sealant within 24 hours while its original bioactivity was maintained. The implantation of the fibrin sealant incorporating FGF-2 successfully induced healing of the surface with hyaline cartilage and concomitant repair of the subchondral bone at eight weeks after the creation of the defect.

Our findings suggest that this delivery method for FGF-2 may be useful for promoting regenerative repair of full-thickness defects of articular cartilage in humans.