Prosthetic joint infections (PJI) occur in 0.8–1.9 % of arthroplasties, but the absolute number is increasing because of the frequency of procedures. Two stage exchange is the most effective strategy, but failures are often described. Culture of perioperative tissues during removal of arthroplasty is a standard procedure but culture during second step is equally important to define a success or a failure.

We retrospectively reviewed PJI treated with two stage-exchange from January 2011 and December 2012 at “Ospedale S. Maria Misericordia”, Albenga-Italy. The procedure calls for bacterial culture not only during first step but also during reimplantation. Antibiotic treatment is prolonged after reimplantation until the cultures availability. A failure was defined by persistence of infection for positive culture or reocurrence of infection during a follow up of at least 2 years in patients with negative cultures. Three positive cultures yielding phenotypically identical organisms, or a single specimen of a virulent microorganism (e.g. Staphylococcus aureus) were required to rule out false positive for contaminants. Patients with persistence of infection were treated for 3 months with antibiotics.

86 patients underwent the two stage treatment: 45 hip and 41 knee prosthesis. The average ESR before arthroplasty removal was 59 mm/ 1st h (range 5–120), the average CRP was 3.9 mg/dl (range 0.3 – 34). Coagulase-negative staphylococci were isolated in 31 cases, Staphylococcus aureus in 19, Streptococcus spp in 8 and enterococci in 4. Gram-negatives were isolated in 4 patients and polymicrobial infection in 6 patients. In 14 patients (16%) no pathogen was identified.

A positive culture during reimplantation was documented in 11 (13%) cases: 8 coagulase-negative staphylococci, 2 Staphylococcus aureus, 1 Candida sp. All patients received 3 months of therapy after surgery and 6 of them were free of infection at 2 years of follow up after the end of treatment. Among the 75 patients with negative cultures, a relapse was documented in 2 (3%), after 5 and 24 months, respectively. These cases were treated with arthrodesis and 6 weeks antibiotic treatment, with resolution of infection but poor functional results. Overall the success rate of our strategy was 92% (79/86).

In patients treated with two-stage exchange, the combination of cultures at reimplantation and antibiotic suppressive treatment for 3 months in presence of positive cultures, are associated with a high rate of success. Only a prolonged follow up can rule out a relapse and agree with a true resolution of infection.

In bone infections, it is of fundamental importance to wrap any orthopaedic surgical procedure in healthy vascularised soft tissue, in order to allow good healing and to prevent infection recurrence.

Vitality of soft tissues around the knee joint can be easily jeopardized in patients undergoing multiple surgical operations as in case of infected arthroprostheses. In addition, there are very few local options in the soft tissue reconstruction of this area, due to the fact that the vascularisation of skin and subcutaneous tissue is based on the genicular arteries’ axes which prohibits the use of random skin flaps.

Preoperative planning of cutaneous incisions and reconstructive procedures is mandatory for a correct surgical treatment.

We analyze retrospectively a series of 8 patients who underwent soft tissue reconstruction of the knee area with local flaps, considering criteria and indications in the choice of each surgical option.

Main variables considered in decision-making were size and location of soft tissue defect, planned orthopaedic surgical procedure, likeliness of the need for further surgery, age, local and general condition of the patient.

Flaps employed have been medial gastrocnemius muscular flap, reverse ALT fasciocutaneous flap and the “propeller” freestyle perforator flap.

Main complications observed have been partial flap necroses and recurrence of the underlying bone infection.

In this work, the authors want to emphasize the importance of a multidisciplinary treatment of bone and prosthetic infections, where the antimicrobial therapy chosen by the Infectious Diseases Specialist must be synergic with an “orthoplastic” surgical procedure, in the effort to reduce the risk of infection persistence or recurrence and to obtain the best possible functional result and quality of life for the patient.

Aims: Clinical use of BMP-7: actual situation The tibial pseudoarthrosis. The Friedlander paper can be considered the only golden standard about the clinical application. It is a prospective, randomized clinical trial comparing BMP-7 with fresh bone autograft. The results of the BMP-7 are similar under to use of fresh bone autograft. Some cases of very serious pseudoar-throsis treated with BMP-7 have demonstrated an high percentual of clinical recovery. In UOA of traumatology and in I Orthopaedic Clinic of Turin University the pseudoarthrosis are treated with the Ilizarov’s technique, not with the autologous transplantation, so Friedlander’s results are not discriminant for the our work.

Methods: In our department the guide lines for BMP-7 application are:

Delayed union of the docking point in pseudoarthrosis of long bones treated with the Ilizarov technique (resection and distractional osteogenesis) and traditional techniques (decortication and fresh bone autograft) not suitable for application. The treatment of a pseudoartrhosis is based on our classification in type: I, II, III, IV (septic).

Results: From 30/09/2002 till 28/02/2007 55 patients have been treated with BMP-7. In 5 cases it has been associated with autologus bone graft. The material is: 24 cases of traditional techniques failure, 17 cases in wich traditional techniques were unfeasible to be treated and 9 docking point nonunions, in 5 particular cases. Mean age is 38 years. Before last intervention, mean number of porevious operation is 6,5 with mean time before BMP procedures is 3 years. 43 patients healed, 9 are under treatment and 3 are failure. The mean time of healing was 4 months.

Conclusions: The series is strictly observational but results are effective in front of the complexity of cases. Late complications suggest that BMP-7 induces bone formation but mechanical function could need time to be achived.According to literature the BMP-7 should be usefull also in more simple cases but more prospective clinical double blind randomised series and cost decreasing are necessary to extend the indications for BMP-7 application.

1. Use of OP1: present situation

1.1 Tibial pseudoarthrosis. The work by Friedlander can be considered golden standard about the clinical application. It is a prospective, randomized clinical trial comparing OP-1 with fresh bone autograft. Results of the two techniques are similar under the clinical and radiographical point of view(1). Some cases of very serious pseudoarthrosis treated with OP1 have demonstrated an high percentual of clinical recovery(2). In the I Orthopaedic Clinic of Turin University pseudoarthrosis are treated with Ilizarov technique, not with the autologous transplantation, so Friedlander’s results are not discriminant for the our work.

1.2 Australian study of 163 patients with amputation risk was done an attempt with OP1 application, before of his commercialisation. In these cases the drug demonstrated to be very efficacious(3).

1.3 Concerning the fresh fractures, experience is limited to prospective, randomised, multicenter clinical trial. The conclusions are a reduction of consolidation delay and the number of reoperation in the OP1 treated group versus the not treated one(4).

2. In the I Orthopaedic Clinic of Turin University (UOSD Muscle-Skeletal Traumatology and External Fixation) guide lines for OP1 application are:

2.1 Delayed union of the docking point in pseudoar-throsis of long bones treated with the Ilizarov technique. OP1 is also used if traditional techniques are not suitable for application

2.2 Traditional techniques failure

2.3 First treatment in very difficult cases of limb reconstruction and bone nonunion

3. From 30/09/2002 till 27/09/2004, 19 patients have been treated with OP1. Middle age is 38 years (range 22–65). Before last intervention, middle number of operation is 6,5 (range 3–26) with middle time treatment of 4 years (range 1–31). 12 healed, 5 are under treatment and 2 are failure (osteomyelitis relapse). 10 tibias, 7 femurs, 1 humerus and 1 forearm were treated. The middle time of healing was 4 months (range 2–6).

Healing has been evaluated by clinical and radiographical point of view (handly evaluation of stability, function recuperation and image of bone consolidation). Radiographic images of bone consolidation are not strictly correlated with clinical stability and function recovery.

4. Conclusion:

4.1 The series is strictly observational. However results are satisfying, given the complexity of treated cases. More prospective randomised double blind clinical studies, and drug cost decrease are necessary to extend the indications for OP1 application.