Septic arthritis is a therapeutic emergency with a high mortality rate (about 11%)(1). Inadequate treatment can cause permanent joint damage. Management of the septic arthritis includes prompt antibiotic treatment as well as joint-decompression and removal of purulent material(2). It is still discussed controversially and there is little evidence which surgical concept is preferable: arthroscopy with lavage and debridement or open arthrotomy with synovectomy(3,4). The aim of the study was to compare efficacy of arthroscopy and arthrotomy in patients with septic gonarthritis.

We evaluated 70 consecutive patients who underwent arthroscopy or arthrotomy at our clinic, because of a bacterial monarthritis of the knee between 2002 and 2010. Our primary outcome was the early recurrence of infection (> 3 months after surgery), which made a second surgery necessary. We compared patients who suffered reinfection and those who did not, in regard to the surgery type as well as potential confounders like comorbidity (measured by Charlson comorbidity index), age, body mass index (BMI), Gächter's -, Kellgren and Lawrence - and Outerbridge classification, duration of symptoms and inflammatory parameters. Furthermore we evaluated differences of the confounders between the surgery groups.

From the 70 patients 41 were treated arthroscopic and 29 with arthrotomy. In total eight patients (11.4%) had to undergo a second surgery because of early reinfection. The rate was significantly higher in patients treated with arthrotomy (n=6; 20.7%) compared to those treated with arthroscopy (n=2; 4.9%) (p=0.041). Whereas we found no significant influence of potential confounders between the reinfection group and the group where primary eradication was achieved. Patients who underwent arthrotomy were significantly older, had more comorbidities (both p<0.001) and higher grades of osteoarthritis according to Kellgren and Lawrence classification (p=0.023). In order to adjust the study population towards confounders we performed a subgroup analysis on patients of the second and third age percentile. When we repeated our analysis we still found a significant higher reinfection rate in the arthrotomy group (p=0.036). At the same time there were no differences in prevalence of confounders, neither between the two surgery groups, nor between the reinfection and the primary eradication group.

Patients with bacterial monarthritis of the knee who were treated with arthroscopy had a significantly lower reinfection rate than those treated with arthrotomy. As arthroscopy is the less invasive and more sufficient method it should be considered the routine treatment according to our data.

Background: Endoprosthetic reconstruction has become the gold standard of treatment after the resection of tumors around the proximal femur, however, the rate of complications linked to megaprostheses is clearly higher than with standard implants. Aim of this study was to investigate the incidence and type of complications related to modular proximal femur prostheses.

Patients and Methods: By retrospective database analysis of the Vienna Tumor Registry, we evaluated the incidence of complications in 170 consecutive patients who have received a proximal femur KMFTR/GMRS at our institution between 1982 and 2007. 71 patients with an average age of 41.7 years (range 18.2–79.9 years) received the implant following the resection of a malignant bone tumor, 95 patients with an average age of 61.7 years (range 5.9–84.2 years) due to metastatic disease. The average time of follow-up was 3.5 years (SD ±4.9 years).

Results: Overall patient survival at five years was 32%. For patients with metastatic disease the overall survival was 10% at five years. Patients being treated for a primary bone tumor had an overall survival of 55% at 5 years. The overall survival of the prosthesis was 90% at two years and 72% at five years. Twenty-one patients (12.65%) suffered from dislocation after a mean time of 6.5 month (range 0.3–33 months) after surgery. Out of these, nine had to be treated by open reduction. Nine patients suffered recurrent dislocation after their first event. Patients who underwent extensive pelvic reconstruction had a significantly higher dislocation rate (33.3%) compared to patients with no or standard acetabular components (11.2%). Deep infection occurred in twelve patients (7.3%) after a mean of 39 months (range 1–166 months) after surgery. Treatment of infection was one-stage revision in eight and hip disarticulation in one patient. Two patients were successfully treated by local wound revision. One patient died of septic shock four days after surgery. Re-infection occurred in three patients. Aseptic loosing occurred in 13 patients (12.8%) after a mean time of 75.6 months (range 1–223 months) after surgery. Revision surgery was necessary in 27 patients (15.8%) with a mean time to first revision of 32 months (range 0.3–116 months). Prosthetic fracture was found in two patients. Local recurrence occurred in 14 patients (8.4%). In seven patients (4.2%) amputation was necessary.

Conclusion: Modular endoprosthesis allow excellent reconstruction of the proximal femur following tumor resection. However, the main complications, dislocation and infection, still remain considerable drawbacks.

Introduction: Little data are available about the incidence and the management of hip dislocation following the implantation of megaprosthesis of the proximal femur, which is one of the main complications following this procedure.

Material and Methods: 190 patients, who received a proximal femur KMFTR/GMRS at our institution between 1982 and 2007, were retrospectively reviewed with regard to the incidence of hip dislocation as well as the success rate of the subsequent surgical/non-surgical treatment. A proximal femur tumor endoprosthesis was used in 148 patients following the resection of a malignant tumor and in 43 patients in severe revision cases following total hip arthroplasty. The average age at the time of surgery was 48 [6a to 83a] in the tumor group and 57.3 [45a to 78a] in the revision group. All of the revision cases and 12 patients from the tumor group had additional revision cups, such as the Schoellner pedestal cup.

Results: 12.3 % (18/147) of the tumor patients and 13.9% (6/43) of the revision cases dislocated at least once. 66.7% (12/18) of the first dislocations from the tumor and 50 % (3/6) of the revision group were treated with closed reduction, the rest required surgery. All patients received an abduction cast for at least 8 weeks. 38% (7/18) of the dislocated hips of tumor group (4.8% [7/147] total) and 67% (4/6) of the revision group (9.3% [4/43] total) experienced a second dislocation. 57% (4/7) of the dislocations from the tumor and 100 % (4/4) of the revision group were treated with closed reduction. Three patients from the tumor group (2% [3/147] total) experienced a total of three dislocations and one patient four dislocations (< 1% [1/147] total). The first dislocation occurred in 88% of the cases within 5 months following surgery during activities of daily living. 82% of the second dislocations and all third dislocations occurred within 4 months of the previous dislocation. Interestingly, no significant difference was found in the rate of re-dislocation between surgical and non-surgical treatment in either group.

Discussion: Dislocation of a proximal femur tumor endoprosthesis is an early complication following surgery and continues to be a challenging condition to treat, especially in cases with extensive soft-tissue defects. Since 2000, a polyester ligament is successfully used in our institution as a reinforcement to reduce the risk of hip dislocation in proximal femur tumor endoprosthesis. Surgical and non-surgical methods to reduce the risk of hip dislocation are discussed.