The use of megaprostheses for knee reconstruction after distal femur resection in young bone sarcoma patients has become popular since early ′80. The authors reviewed their experience with different distal femur megaprostheses in children. Clinico-radiographic evolution in a consecutive series of 113 children, that had implanted below age 15 (range 6-14) a distal femur megaprosthesis in the period 1984-2007, was analized. A modular implant was used in 97 cases with uncemented femoral stem (three different models along the period). The implant presented fixed-hinge joint in 78 cases while rotating-hinge knee was utilized in 19 cases. In 39 cases the fixed-hinge joint had a tibial component with a polished stem to allow the residual growth of proximal tibia; in two cases a mechanically extendable prosthesis was used. A custom-made noninvasive extendable prosthesis with cemented femoral stem and smooth uncemented tibial stem was used in 15 cases since 2002. Radiological and functional results were analysed and a statistical comparison of implant outcome according different stems was obtained.Aim
Method
Reconstruction following internal hemipelvectomy for bone tumors remains a major surgical challenge. Most of the cases are considered not suitable for reconstruction because of high complication occurrence. Allografts coupled with standard prosthesis is a reliable method of reconstruction. 26 patients received a McMinn stemmed cup (Link, Germany) after periacetabular tumor resection from February 1999 to 2006. In 18 patients the reconstruction followed resection of the acetabular area while in other 8 an extrarticular resection of the proximal femur was performed. In 21 cases a stemmed acetabular cup were associated with massive bone allograft. There were 13 female and 13 male with a mean age of 41 years (13 to 70). Average follow-up was 45 months (7 to 105). Six patients were affected by local recurrence of the tumour and five underwent hindquarter amputation. In 4 of them the index surgery followed a previous recurrence of the tumour. Finally 6 patients died for related causes within 2 years. All the other 20 have been followed clinically and radiographically for a minimum of 24 months. Deep infection occurred in one case, there were no cases of dislocation. Radiolucency at the prosthesis-bone interface was observed in 3 cases, 2 patients had proximal migration <
of 20 mm. Only one patient was treated for aseptic loosening because of incorrect initial position of the implant. The iliac osteotomy was consolidated in all cases, while a delayed union was frequently observed in the pubic osteotomy, however without compromise the stability of implant. Functional result were evaluated according to the MSTS system and this showed 65% of excellent or good clinical results. The procedure requires appropriate patient selection, accurate preoperative planning, meticulous selection and preparation of allograft. Usually artificial ligaments are applied to reduce hip instability, however, this type of reconstruction do not require complex fixation, thus reducing surgical time and early complications.
Long-term clinical study to explore the curative effect and mechanism of the treatment of adult chronic osteomyelitis by implant Osteoset T. The study object were 65 case adult chronic osteomyelitis patient from November 1977 to April 2003 in a University-based hospital. Age ranged from 18 to 69 years old. 40 cases were treated by general debridement (Method I); 25 cases were treated by general debridement and implant Osteoset T in dead space (Methods II). Stage IA(The UTMB Staging System) osteomyelitis 39 cases; The Organism was Staphylococcus Aureus 28 cases. In all cases (group A), 40 cases were treated with Method I (group AI), 25 cases were treated with Method II (group AII). The majority of the patients, 39 resulted as Stage IA (group B); 22 were treated with Method I (group BI) and 17 cases were treated with Method II (groupBII). Finally, 28 patients were chronic Staph Aureus osteomyelitis (Group C); 13 were treated with Method I (group CI) and 15 cases with Method II (group CII); Followed from 36 to 334 months, mean 75.0 months. Then respectively evaluate and analysis analyze the success rate of different method with standard. The success rate of group BI was 59.09%, group BII was 94.12%, contrast the success rate there was significant difference (p<
0.05). The success rate of group AI was 60.00%, group AII was 80.00%. The success rate of group CI was 46.15%, group CII was 80.00%. The use of Osteoset T has demostrated better healing rate than left the empty cavity there after debridement and irrigation. Osteoset T can local delivery antibiotic, filler of the dead space, It can be mixed with different antibiotics, reduces the hospitalization time, reduces the number of operation. Unfortunately, Osteoset dos not help with the bone growth.
Infection was reported in 15 patients (24.2%): 2 early infections (healed with surgical debridment), 1 femoral stem septic loosening (treated with early revision with cemented stem); in 8 cases removal of the infected APC was required followed by implant of a new prosthetic device after cement spacer; two infections did not healed and patient underwent amputation; in two cases a good functional result was achieved removing the infected graft and covering the proximal tibia with cement and no other surgery was required. Non union of the graft was observed in 8 patients (12.9%): in 4 patients autologous bone grafting was necessary to heal the osteotomy line. In other 3 cases non union was associated with graft fracture. In one case non union was associated with tibial stem loosening and revision of the whole implant was done. Polyethylene wear was assessed in 5 patients (8%) and revision of the polyethylene components was always required. Nine patellar tendon rupture (14.5%) were assessed and repaired was performed in seven cases. The functional outcome of 42 patients with more than two years of follow up was excellent in 25 cases, good in 13, fair in 2 and poor in 2.