When performing limb salvage operations for malignant bone tumours in skeletally immature patients, it is desirable to reconstruct the limb with a prosthesis that can be lengthened without surgery at appropriate intervals to keep pace with growth of the contra-lateral side. We have developed a prosthesis that can be lengthened non-invasively. The lengthening is achieved on the principle of electromagnetic induction.

The purpose of this study was to look at our early experience with the use of the Non Invasive Distal Femoral Expandable Endoprosthesis. A prospective study of 17 skeletally immature patients with osteosarcoma of the distal femur, implanted with the prosthesis, was performed at the Royal National Orthopaedic Hospital, Stanmore. The patients were aged between 9 and 15 years (mean 12.1 years) at the time of surgery. Patients were lengthened at appropriate intervals in outpatient clinics. Patients were functionally evaluated using the Musculoskeletal Tumour Society (MSTS) Scoring System and the Toronto Extremity Severity Score (TESS). Average time from the implantation to the last follow-up was 18.2 months (range 14-30 months). The patients have been lengthened by an average of 25mm (4.25-55mm). The mean amount of knee flexion is 125 degrees. The mean MSTS score is 77% (23/30; range 11-29) and the mean TESS score is 72%. There have been two complications: one patient developed a flexion deformity of 25 degrees at the knee joint and one patient died of disseminated metastatic malignancy.

The early results from patients treated using this device have been encouraging. Using this implant avoids multiple surgical procedures and general anaesthesia. This results in low morbidity, cost savings and reduced psychological trauma. We do need additional data regarding the long-term structural integrity of the prosthesis.

Background

Endoprosthetic reconstruction is an established method of treatment for primary bone tumours in children. Traditionally these were implanted with cemented intramedullary fixation. Hydroxyapatite collars at the shoulder of the implant are now standard on all extremity endoprostheses, but older cases were implanted without collars. Uncemented intramedullary fixation with hydroxyapatite collars has also been used in an attempt to reduce the incidence of problems such as aseptic loosening. Currently there are various indications that dictate which method is used.

Aim: The purpose of this study was to evaluate the extent of neurological deficit following excision of spinal neurofibromas.

Methods: Retrospective case series, combined with contemporary neurological examination and outcome questionnaires.

Results: 46 patients (26 males, 20 females) with a mean age of 46 between the years of 1985 – 2005. The incidence of neurological deficit subsequent to nerve sectioning to remove the tumour was 28/46 (60.9%) in the acute period. In the long term this reduced to 28%.

Conclusions: Despite the sectioning of nerves during surgery motor or sensory deficit was surprisingly rare. It was mainly sensory and recovered with time. This is presumably due to neural plasticity and dermatomal overlap. These results provide useful information for surgeons to counsel their patients preoperatively.

Purpose: We report a series of 58 patients with metastatic bone disease treated with resection and endoprosthetic reconstruction over a 5 year period at our institution.

Introduction: The recent advances in adjuvant and neo-adjuvant therapy in cancer treatment has resulted in improved prognosis of patients with bone metastases. Most patients who have an actual or impending pathological fracture should have operative stabilisation or reconstruction. According to BOA guidelines patients should undergo a single procedure which allows early full weight bearing and lasts the expected lifespan of the patient. The use of modern modular endoprostheses allows these criteria to be met.

Methods and Results: We retrospectively identified all patients diagnosed with metastatic disease to bone between 1999 to 2003. 171 patients were diagnosed with bone metastases. Metastatic breast and renal cancer accounted for 47% of the lesions. 58 patients with bone metastasis to the appendicular skeleton had an endo-prosthetic reconstruction. There were 28 males and 30 females. 11 patients had lesions in the upper extremity and 47 patients had lesions in the lower extremity. Mean age at presentation was 62 years (24 to 88 years). 19 patients are still alive, 34 patients had died and 5 were lost to follow-up. Patients died of disease at a mean of 22 months (2 to 51 months) from surgery. Mean follow-up was 55 months (24 to 78 months). There were 5 wound infections, 1 aseptic loosening, 3 dislocations, 1 subluxation and 1 prosthesis rotated requiring open repositioning. Patients were followed up and evaluated using the Musculoskeletal Society Tumour Score (MSTS) and the Toronto Extremity Salvage Score. The mean MSTS score was 73% (57 to 90%) and TESS was 71% (84 to 95%).

Conclusions: We conclude that endoprosthetic replacement for the treatment of bone metastases in selected cases achieves the aims of restoring function, allowing early weight bearing and alleviating pain. The complication rate is low.

Introduction: Since 1975, 6 types of extendable endo-prostheses have been developed at Biomedical Engineering, UCL, and Stanmore Implants Worldwide in conjunction with the surgeons at this centre.

Aims: To establish whether developments in design have had the desired effect of improving both implant survivorship and functional outcome.

Methods: This was a retrospective study using case notes, hospital databases and a radiological review, combined with contemporary functional outcome assessments (MSTS, TESS, SF36).

Results: 161 consecutive prostheses in 138 paediatric patients, between the years of 1983 – 2005, were implanted for primary bone tumours. Mean age was 10.3 (3 – 18), 81 were males and 57 females. There were 136 primary procedures and 25 revisions.

6 prostheses that used ball bearings to achieve length (designed in 1981) were implanted, 3 (50 %) were revised due to mechanical failure.

19 prostheses that utilised external C-washes (1998) to achieve length were implanted, 6 (32 %) were revised, half of these for mechanical failure.

Of the 98 minimally invasive prostheses (1992) that utilized an Allan key and screw-jack mechanism to lengthen, 14 (14 %) were revised, half of these for infection.

17 non-invasive extendable endoprostheses (2001) that are lengthened by electromagnetic coupling have been implanted so far. There has only been 1 (6 %) revision. This was due to full extension being reached.

Conclusions: Design improvements in growing endoprostheses since 1983 have led to improved survivorship. Initially this led to a reduction in mechanical failure and latterly to a reduction in infection, as indications for revision.

Key Words: Bone tumour, children, endoprosthesis, survivorship.

Purpose: We report a series of patients with malignant tumours of the pelvis that had a tissue expander inserted in the pelvis to facilitate radical radiotherapy, and report functional outcomes following treatment.

Introduction: Surgery for malignant tumours affecting the pelvis is challenging. Some tumours are suitable for internal hemipelvectomy and reconstruction, some require hindquarter amputation and some are inoperable. Overall prognosis is poor with high morbidity and mortality rates. There may be a place for alternative treatment with the insertion of pelvic spacers to facilitate radical radiotherapy. This is indicated in patients who have an inoperable tumour, who decline amputation, or who had an internal hemipelvectomy with close margins and high risk of local recurrence.

Methods & Results: We performed a retrospective review of all patients who presented with a malignant tumour of the pelvis and who underwent an insertion of a pelvic spacer followed by local high dose radiotherapy. Available patients were followed up and evaluated using the Musculoskeletal Society Tumour Score (MSTS) and the Toronto Extremity Salvage Score (TESS). There were ten patients; 5 had Ewing’s sarcoma, 3 had osteosarcoma, 1 had spindle cell sarcoma and 1 had alveolar soft part sarcoma. 4 patients had metastases on presentation. The average age was 30 years (14 to 56 years), and average follow-up was 15 months (12 to 24 months). 4 patients died and 6 are still alive. There were no surgical complications. The average length of hospital stay was 6 days (2 to 10 days). Patients averaged an MSTS score of 63% and a TESS of 67%.

Conclusion: Radical radiotherapy after spacer insertion offers an alternative to morbid surgery and is associated with good functional outcomes.

Background: Extra-compartmental limb soft tissue sarcomas are notoriously difficult to treat. These tumours can exhibit macro or microscopic spread beyond the confines of normal anatomical barriers and require radical resection, often necessitating excision of bone as well as soft tissue. This will inevitably affect the patient’s functional outcome. The primary operations for these aggressive sarcomas include wide local excision of soft tissue and adjacent involved bone, radical resection with endoprosthetic reconstruction and amputation.

Methods: 85 patients who underwent such an operation between 1995 to 2000 were reviewed and categorised according to whether they received wide local excision, endoprosthesis reconstruction or amputation. Patient demographics, sarcoma details, recurrence and survival rates were identified and compared between the three groups. Functional outcomes in the 45 patients still alive were assessed using TESS and MSTS scores.

Results: Mean age was 61 years (range 8 to 92). There were 51 males and 34 females. Anatomical distribution was as follows: arm 26, leg 47, pelvis 8 and other 4. The commonest histology subtypes were MFH, leiomyosarcoma and undifferentiated soft tissue sarcoma. 17 had wide local excision of bone and soft tissue, 32 underwent endoprosthesis reconstruction and 36 underwent primary amputation. Recurrence rates were highest in the endoprosthesis group at 19%. Five year survival was worst in the amputation group at 49%. Functional outcomes were highest in the wide local excision group, and similar in the other two surgical groups.

Conclusions: Unsurprisingly survival is poorest in the primary amputee group because of the highly aggressive nature of these sarcomas, despite having the most radical treatment. The similar functional outcomes shown between endoprosthesis reconstruction and primary amputation may be influential when considering cases in which this decision is unclear and function is the main issue at stake.

Purpose: We report the clinical and functional outcome of limb salvage surgery and endoprosthetic reconstruction of the distal tibia and ankle joint in 5 patients.

Introduction: The distal tibia is an uncommon site for primary malignant bone tumours and the treatment of choice for most patients is a below knee amputation. Patients who decline an amputation may be offered an endoprosthetic replacement. This is a technically challenging operation and may be associated with high morbidity.

Methods and Results: Over 25 years at our centre, 5 patients underwent distal tibial replacements for bone or soft tissue sarcomas. Two had osteosarcoma, one had a recurrence of Ewing’s sarcoma, one had malignant fibrous histiocytoma, and one had an adamantinoma. The mean age was 37 years (13 to 69 years). There were no tumour recurrences. Four patients developed complications with wound infection. Two of these resulted in below knee amputations. Average follow-up was 31 months (19 to 55 months) with 1 patient lost to follow-up. Patients were evaluated using the Toronto Extremity Salvage Score (TESS) and the Musculoskeletal Tumour Society (MSTS) score. The mean MSTS score was 88% and the mean TESS was 88.5%. Two patients who later had a below knee amputation and who were using a prosthesis averaged an MSTS score of 86.3% and a TESS of 89.3%.

Conclusion: For those patients who are unwilling to undergo an amputation for malignant tumours of the distal tibia, endoprosthetic reconstruction is an alternative, but at the cost of increased risk of significant complications, functional deterioration and morbidity. There was little difference between functional scores for patients who proceeded to have a below knee amputation compared to patients who still had their endoprosthesis