Objective of this study was to analyse results of two stage revisions in infected megaprostheses in lower limb.

Material and Methods: Between April 1983 and December 2007, 1036 modular uncemented megaprostheses were implanted in 605 males and 431 females with mean age 33.5 yrs: 160 KMFTR®, 633 HMRS® prostheses, 68 HMRS® Rotating Hinge and 175 GMRS®. Sites: distal femur 659, proximal tibia 198, proximal femur 145, total femur 25, distal femur and proximal tibia 9. Histology showed 612 osteosarcomas, 113 chondrosarcomas, 72 Ewing’s sarcoma, 31 metastatic carcinomas, 89 GCT, 36 MFH, 68 other diagnoses.

Infection occurred in 80 cases (7.7%) at mean time of 4 yrs (min 1 month, max 19 yrs) in 18 KMFTR®, 47 HMRS®, 5 HMRS® Rotating Hinge, 10 GMRS®. Sites: 51 distal femurs, 21 proximal tibias, 6 proximal femurs, 1 total femur and 1 extrarticular knee resection. Most frequent bacteria causing infection were: Staphilococcus Epidermidis (39 cases), Staphilococcus Aureus (17) and Pseudomonas Aeruginosa (5). Infection occurred postoperatively within 4 weeks in 9 cases, early (within 6 months) in 12 cases, late (after 6 months) in 59 cases.

Usual surgical treatment was “two stage” (removal of implant, one or more cement spacers with antibiotics, new implant), with antibiotics according with coltures. One stage treatment was used for immediate postoperative infections, only since 1998.

Functional results after treatment of infection were assessed using the MSTS system.

Results: A two stage revision was attempted in 73 pts (91.2%): in 58 cases a new prostheses was implanted (with negative laboratory tests for infection) at mean time of 5 months (min 2, max 16 months), but in 3 pts infection recurred and they were amputated; 4 pts died before implanting a new prosthesis; 11 pts were amputated after several spacers since infection did not heal. One stage revision was performed in 4 of the 9 immediate postoperative infections, with successful results.

In 3 cases an amputation was primarily performed, to proceed with chemotherapy.

Revisions for infection were successful in 63 pts (79%), while 17 pts were amputated (21%).

Functional results evaluated in 53 revised cases were good or excellent in 43 (81.1%).

Conclusions: Two stage treatment of infected megaprostheses is successful in most cases. One stage has selected indications, mainly in postoperative immediate infections.

Introduction: Tumours of sacrum are rare. Treatment depends on malignancy or local aggressiveness: resection is indicated for malignant lesions, intralesional surgery for benign. Purpose of this study was to analyse risk of infection and its treatment after surgery for the two most common primary sacral tumours.

Material and Methods: Between 1976 and 2005, 82 patients with sacral chordoma or giant cell tumour were treated in our Institution. Demographic data, surgery and adjuvant treatments were analysed in the two histotypes. All patients were periodically checked with imaging studies. Special attention was given to the assessment of deep infections, their treatment and outcome.

Patients included 44 females and 38 males, ranging in age from 14 to 74 years. Mean follow-up was 9.5 years (min. 3, max. 27). Histopathological findings included chordomas in 55 cases and giant cell tumor (GCT) in 27. Most pts. had iv antibiotic therapy with amikacin and teicoplanin. Surgery of chordoma was resection, surgery of GCT was intralesional excision. In 6 sacral resections a miocutaneous transabdominal flap of rectus abdominis was used for posterior closure.

Results: No deep infections were observed in the GCT series. Three patients with sacral chordoma died for postoperative complications and were excluded from this analysis. Of the remaining 52 patients with chordoma, 23/52 had deep wound infection (44%), that required one or more additional operative procedures. In 16 pts. (70%) infection occurred within 4 weeks postoperatively, in 7 within 6 months. Most frequent bacteria causing infection were Enterococcus (23%), Escherichia Coli (20%), Pseudomonas Aeruginosa (18%). In 74% of cases a multiagent infection was detected. Surgical treatment consisted in 1 (52%) or more (48%) surgical debridements, combined with antibiotics therapy according to coltural results.

Mean surgical time was 14 hours for resections and 6 hours for excisions.

No significant difference was found comparing deep wound infections with levels of resection (15/33 resections proximal to S3-45% and 8/19 resections below or at S3-42%), previous intralesional surgery elsewhere (4/9 patients previous treated elsewhere-44% and 19/46 primarily treated patients-41%) and age at surgery.

Conclusions: Type of surgery was the prominent factor related with a major risk of infection. Operating procedure time correlated as well. Resection of sacral chordomas with wide margins improves survival although extensive soft-tissue resection in proximity to the rectum favours deep infections. Intralesional excision is the recommended surgical treatment for GCT of the sacrum and does not imply a significant risk of infection.

Objective: Aim of this study was to analyse the incidence of infections in primary prosthetic reconstructions of the humerus after resection for bone tumours and their treatment and results.

Material and Methods: Between 1974 and 2006 at Rizzoli 344 reconstructions of the humerus using prosthetic devices (alone or in association with allografts) were performed. Sites of reconstruction were: proximal humerus 311, distal humerus 19, diaphysis 5, total humerus 9. Histological diagnoses included 24 benign tumors, 253 malignant tumors and 67 metastatic carcinomas. Patients were followed periodically in the clinic. Informations were obtained from clinical charts and imaging studies with special attention to major complications requiring revision surgery. Univariate analysis through Kaplan-Meier actuarial curves was used in evaluating implant survival to major complications. Infections developing in the first 4 weeks were considered postoperative infections, those diagnosed in the first 6 months were judged early infections, while late infections those diagnosed after 6 months from surgery.

Results: In 20 patients (5.8%) a revision for deep infection was required. In 19 of these cases tumor was localized in the proximal humerus and in 1 in the distal humerus. There were 18 infections in prostheses and 2 in allograft prosthesis composites. Two infections were postoperatively diagnosed, seven were early infections and eleven late infections. Revision was required in 18 cemented prosthesis, 1 uncemented prostheses and 1 Coonrad-Morrey.

S. Epidermidis and S. Aureo were the most frequent bacteria causing infection (45%). Two stage treatment of infection was chosen: removal of the implant and temporary substitution with cement spacer with antibiotics (usually vancomycin) until infection healed. But a new prostheses was actually implanted in 3 cases only (at mean time of 5.7 mos), while in 17 the spacer was never removed by patients choice due to the acceptable result with the spacer. Systemic antibiotics were associated according to cultural results. Infection healed in all patients.

Conclusions: Infection is the most severe complication in prosthetic reconstructions for tumours of the humerus. Its incidence (5.8%) is lower than in lower limb. Treatment requires a team work: surgeon, microbiologist and infectious disease physician. One stage is indicated in postoperative infections, two stage is recommended in both early and late infections. Two stage surgery offered good results, although in most cases a new prosthesis was not implanted, since actually humeral megaprostheses act as a spacer and don’t provide a much better function.

Gorham-Stout disease (GSD) is rare, characterized by proliferation of vascular channels resulting in progressive distruction of bone. In the Rizzoli files we found 15 cases of GSD from 1968 to 2008. Two were excluded for insufficient documentation. For 13 cases clinical data, imaging and histology were analysed. Histopathologic features included benign vascular proliferation, vascular pattern of osteolytic angioma, fibro-connective tissue component and bony destruction. A final diagnosis was established based on clinical, radiological and histopathologic features.

Imaging included X-rays in 11 cases and CT or MRI in 5. All lesions were lytic, with associated sclerosis in two cases. There was one lesion only in 4 cases, multiple lesions in the same bone in 1 and multiple bones involved in 6. Primary sites were proximal femur in 7 cases, pelvis in 2, hip and knee, calcaneus, humerus and cervical spine in 1 case each. Two patients had no treatment, 2 conservative treatment (cast or brace), 5 surgery, 6 medical treatment (byphosphonates, calcitonin, zoledronic acid, interferon, steroids), 1 radiotherapy, 2 selective arterial embolization. Surgery consisted of internal fixation of pathologic fractures in 4 patients and reconstruction of the entire humerus with a double composite allograft in 1. Treatment was surgery only in 2 patients, medical treatment in 4 (1 also embolization), surgery and medical treatment in 2 (1 also embolization), radiotherapy only in 1, conservative treatment in 2. Four patients were lost at follow up. Mean follow up was 17 ys.(min 2, max 30) in 9 patients: 2 dead, 3 healed, 3 with stable disease, 1 alive with disease at 24 ys.

No conclusive treatment recommendations are possible; surgery is indicated in pathologic fractures or reconstruction of massively destroyed bones, medical treatment and selective embolization are helpful. In literature prosthetic reconstruction is preferred due to the risk of allografts resorption.

Between 1983 and 2006 at Rizzoli 669 knee modular uncemented prostheses were implanted after resection of the distal femur, total femur or proximal tibia. These prostheses include 126 KMFTR prostheses and 543 second generation HMRS prostheses. Patients were followed periodically in the clinic. Data was obtained from clinical charts and imaging studies with special attention to major complications requiring revision surgery. Revision for polyethylene wear was considered a minor complication, since it did not imply failure of the implant. Functional results were assessed according to the MSTS system. Since data could be misleading due to deaths in an oncologic population (although 2/3 of patients were cured or long survivors), to censore the implant unrelated events Kaplan-Meyer curves of implant survival were studied.

In 126 KMFTR group infection rated 13.5%, stem breakage 13%, aseptic loosening 9.5%; change of polyethylene rated 44%. In 543 HMRS prostheses infection rated 8.6%, stem breakage 3%, aseptic loosening 4.8%; revision for polyethylene wear rated 9.6%. Techniques of revisions and their outcome analysed showed about 2/3 of good results, but increased risk of further complications in revised implants. Functional results (MSTS system) were good or excellent in 80% of KMFTR prostheses and in 90% of HMRS.

Decrease of major complications in newer prosthetic design was statistically significant and possibly due to newer materials and modified stem design. Polyethylene wear also decreased significantly. Function was satisfactory in most patients without complications for both groups. Revision surgery is technically demanding and appropriate timing of revision is crucial, since early treatment can improve final outcome.

From October 2003 to September 2007 at Rizzoli 161 GMRS^® prostheses were implanted after resections of the lower limb. This is a modular system with a knee rotating hinge mechanism, cemented and uncemented stems, in titanium and chromium-cobalt-molybdenum, curved and straight-fluted, with or without hydroxyapatite coating. Adaptors are available to revise HMRS^® prostheses with hybrid implants. This study includes 88 males and 73 females ranging in age from 9 to 80 years. Sites of reconstruction were 109 distal femurs, 19 proximal femurs, 1 total femur and 32 proximal tibias. There were 149 oncologic and 12 non oncologic diagnoses, including 96 primary reconstructions and 65 revisions for failures of previous reconstructions. Analysis of imaging and complications was performed and function assessed according to MSTS system. Kaplan-Meier curves were used to statistically evaluate implant survival.

At a mean follow up of 2.5 yrs. 106 patients are continuously NED, 31 NED after treatment of relapse, 7 AWD, 5 DWD. There were 10 major complications: 8 infections (4.7%) (5 in primary and 3 in secondary implants) and 2 aseptic loosenings (1.2%) (1 each). There were 9 minor complications requiring minor revisions. Comparative statistical analysis of implant survival showed no statistically significant difference between primary and secondary implants. Functional results were good or excellent in 95% of patients, without any poor.

Middle term results are promising with no breakages of implant components. Besides oncological cases, there are selected indications in non oncological settings, such as revisions of prosthetic or allografts failures. While a higher complication rate was expected in secondary implants, statistical analysis shows similar survival.