Diffuse-type Tenosynovial Giant-Cell Tumour (d-TGCT) of large joints is a rare, locally aggressive, soft tissue tumour affecting predominantly the knee. Previously classified as Pigmented Villonodular Synovitis (PVNS), this monoarticular disease arises from the synovial lining and is more common in younger adults. Given the diffuse and aggressive nature of this tumour, local control is often difficult and recurrence rates are high. Current literature is comprised primarily of small, and a few larger but heterogeneous, observational studies. Both arthroscopic and open synovectomy techniques, or combinations thereof, have been described for the treatment of d-TGCT of the knee. There is, however, no consensus on the best approach to minimize recurrence of d-TGCT of the knee. Some limited evidence would suggest that a staged, open anterior and posterior synovectomy might be of benefit in reducing recurrence. To our knowledge, no case series has specifically looked at the recurrence rate of d-TGCT of the knee following a staged, open, posterior and anterior approach. We hypothesized that this approach may provide better recurrence rates as suggested by larger more heterogeneous series. A retrospective review of the local pathology database was performed to identify all cases of d-TGCT or PVNS of the knee treated surgically at our institution over the past 15 years. All cases were treated by a single fellowship-trained orthopaedic oncology surgeon, using a consistent, staged, open, posterior and anterior approach for synovectomy. All cases were confirmed by histopathology and followed-up with regular repeat MRI to monitor for recurrence. Medical records of these patients were reviewed to extract demographic information, as well as outcomes data, specifically recurrence rate and complications. Any adjuvant treatments or subsequent surgical interventions were noted. Twenty-three patients with a minimum follow-up of two years were identified. Mean age was 36.3 at the time of treatment. There were 10 females and 13 males. Mean follow-up was seven and a half years. Fourteen of 23 (60.9%) had no previous treatment. Five of 23 had a previous arthroscopic synovectomy, one of 23 had a previous combined anterior arthroscopic and posterior open synovectomy, and three of 23 had a previous open synovectomy. Mean time between stages was 87 days (2.9 months). Seven of 23 (30.4%) patients had a recurrence. Of these, three of seven (42.9%) were treated with Imatinib, and four of seven (57.1%) were treated with repeat surgery (three of four arthroscopic and one of four open). Recurrence rates of d-TGCT in the literature vary widely but tend to be high. In our retrospective study, a staged, open, anterior and posterior synovectomy provides recurrence rates that are lower than rates previously reported in the literature. These findings support prior data suggesting this approach may result in better rates of recurrence for this highly recurrent difficult to treat tumour.
Diffuse-type Tenosynovial Giant-Cell Tumour (d-TGCT) of large joints is a rare, locally aggressive, soft tissue tumour affecting predominantly the knee. Previously classified as Pigmented Villonodular Synovitis (PVNS), this monoarticular disease arises from the synovial lining and is more common in younger adults. Given the diffuse and aggressive nature of this tumour, local control is often difficult and recurrence rates are high. Current literature is comprised primarily of small, and a few larger but heterogeneous, observational studies. Both arthroscopic and open synovectomy techniques, or combinations thereof, have been described for the treatment of d-TGCT of the knee. There is, however, no consensus on the best approach to minimize recurrence of d-TGCT of the knee. Some limited evidence would suggest that a staged, open anterior and posterior synovectomy might be of benefit in reducing recurrence. To our knowledge, no case series has specifically looked at the recurrence rate of d-TGCT of the knee following a staged, open, posterior and anterior approach. We hypothesized that this approach may provide better recurrence rates as suggested by larger more heterogeneous series. A retrospective review of the local pathology database was performed to identify all cases of d-TGCT or PVNS of the knee treated surgically at our institution over the past 15 years. All cases were treated by a single fellowship-trained orthopaedic oncology surgeon, using a consistent, staged, open, posterior and anterior approach for synovectomy. All cases were confirmed by histopathology and followed-up with regular repeat MRI to monitor for recurrence. Medical records of these patients were reviewed to extract demographic information, as well as outcomes data, specifically recurrence rate and complications. Any adjuvant treatments or subsequent surgical interventions were noted. Twenty-three patients with a minimum follow-up of two years were identified. Mean age was 36.3 at the time of treatment. There were 10 females and 13 males. Mean follow-up was seven and a half years. Fourteen of 23 (60.9%) had no previous treatment. Five of 23 had a previous arthroscopic synovectomy, one of 23 had a previous combined anterior arthroscopic and posterior open synovectomy, and three of 23 had a previous open synovectomy. Mean time between stages was 87 days (2.9 months). Seven of 23 (30.4%) patients had a recurrence. Of these, three of seven (42.9%) were treated with Imatinib, and four of seven (57.1%) were treated with repeat surgery (three of four arthroscopic and one of four open). Recurrence rates of d-TGCT in the literature vary widely but tend to be high. In our retrospective study, a staged, open, anterior and posterior synovectomy provides recurrence rates that are lower than rates previously reported in the literature. These findings support prior data suggesting this approach may result in better rates of recurrence for this highly recurrent difficult to treat tumour.
Stripe wear, observed on retrieved ceramic hip replacements, has only been replicated The aim of this study was to compare the edge loading mechanisms observed under microseparation conditions due to translational mal-positioning conditions simulated on two different hip joint simulators. The components used in this study were zirconia-toughened-alumina ceramic-on-ceramic bearings (36 mm) inserted into titanium alloy acetabular cups (BIOLOX® delta and Pinnacle® respectively, DePuy Synthes Joint Reconstruction, Leeds, UK). Six couples were tested for two million cycles under 0.5 mm dynamic microseparation conditions on the Leeds II hip joint simulator as described by Nevelos et al2 and Stewart et al3 (Figure 1). Ten bearing couples were tested for two million cycles under microseparation conditions achieved in two different ways on the ProSim pneumatic hip joint simulator (SimSol, Stockport, UK). Two conditions were tested; condition (1)- the femoral head was left to completely separate (the vertical motion was controlled at 1 mm) causing it to contact the inferior rim of the acetabular cup before edge loading on the superior rim at heel strike (n = 5) and condition (2)- springs were placed below the plate holding the femoral head to control the tilt of the head laterally towards the rim of the acetabular cup as the negative pressure was applied (n = 5; Figure 1). Wear was assessed gravimetrically every million cycles using a microbalance (Mettler AT201, UK). Three-dimensional reconstructions of the wear area on the heads were obtained using a coordinate measuring machine (Legex 322, Mitutoyo, UK) and SR3D software (Tribosol, UK).Introduction
Materials and Methods
Many authors believe that size, histological grade and depth are the best predictors of outcome in soft tissue sarcoma. Enneking’s surgical staging system included compartmental status, and was intended to guide surgical intervention as well as provide prognostic information. Advances in surgical and radiotherapy techniques may mean that extracompartmental status is no longer a poor prognostic factor. We compared a group of popliteal fossa sarcomas with a group from the posterior thigh, and found that although the former group required more extensive surgery to obtain wide margins, their functional and survival outcomes were similar. No single staging system has been generally accepted for extremity soft tissue sarcoma, although histologic grade, size and depth are widely accepted as prognostic indicators. Enneking outlined a surgical staging system which used compartmental status as a predictor of outcome. However, surgical reconstruction and adjuvant radiotherapy have advanced considerably. We wanted to know if a tumour arising in the popliteal fossa still had poorer survival or functional outcome in the light of these advances. We identified twenty-three patients who had sarcomas of the popliteal fossa and forty-six patients who had sarcomas of the nearby posterior thigh compartment. Popliteal sarcomas were not of a different size or more likely to present with metastasis. Popliteal tumours more frequently required reconstructive techniques such as local or free tissue transfer and skin grafting than posterior thigh tumours (39.1% v 4.3% respectively). Popliteal tumours were also more likely to undergo a dissection or reconstruction of the major neurovascular structures of the lower limb (30.4% v 0% respectively). There was no difference in local or systemic recurrence rates between the groups. TESS and MSTS 1987 functional scores also showed no difference between the groups. We conclude that popliteal fossa sarcomas require a greater level of surgical intervention to follow sound principles of sarcoma resection and achieve reconstruction of the ensuing soft tissue defect. However, if these principles are followed in a planned multidisciplinary setting, then survival and functional results similar to the posterior thigh can be expected.