For which patients is bone-defect-reconstruction with the Masquelet-technique suitable?

Between 11/2011 and 1/2015 we treated 27 Patients (4 female/ 23 male) with bone-defects up to 150mm after septic complications with the Masquelet-technique.

Reason of the bone defects were infected-non-unions of lower extremity, chronic osteomyelitis, infected knee-arthrodesis, chronic upper-ancle-empyema and infect-defect-non-union of the humerus. On average the patients were 47,5 (18–74) years old. The mean bone-defect-size was 62,6 mm (25–150). 26 of the 27 patients came from other hospitals, where they had up to 20 (mean 4,9) operations caused by the infection. The time before transfer to our hospital was on average 177days (6–720). 25 patients receaved flaps because of soft tissue-defects (7 free flaps, 18 local flaps).

13 patients suffered a polytrauma.

In 5 cases the femur, in 3 cases a knee-arthrodesis, in 18 cases the tibia and in 1 case the humerus was affected by infection resulting in bone defects.

Indication for the Masquelet-technique was low-/incompliance in 10 cases due to higher grade of traumatic brain injury and polytrauma and difficult soft-tissue conditions, in 6 times after problems with segment-transport and in 1 case as dead space management.

Positiv microbial detection succeeded in 19 patients at the first operation although most of the patients underwent long term antibiotic therapy. Mainly we found problematic bacteria. At the time of defect reconstruction with spongious graft we found persistant bacteria in 4 cases.

The first operation aimed treating the infection with radical sequestrectomy, removal of foreign bodies and filling the defect with an antibiotic loaded cementspacer as well as external fixation. 6–8 weeks later we removed the spacer and filled the defect with autologous bonegraft. In 2 cases we needed 2 bone grafts to fill the defect. In 9 cases we removed the fixateur and stabilized the defect with an internal anglestable plate.

All patients were examined clinically and radiologically every 4–6 weeks in our outpatient-department for osteitis until full weight bearing and later every 3months

In 22 of 27 cases the infection was clinically treated successfully. 5 patients are allowed for full weight bearing (all with secondary internal plates). No patient underwent amputation.

There were 4 recurrences of infection, 9 instabilities needing internal stabilization and further bonegraft.

For patients with low-/incompliance for various reasons and for those with difficult soft tissue conditions following flaps the Masquelet technique is a valuable alternative to the normal autologious spongegraft and to the segmenttransport. Internal fixation seems necessary.

Introduction: Arthroplasty plays a growing role in our society today. Due to scientific and medical progress there are an increasing number of viable candidates and the improvement of quality of life thereafter speaks for itself.

Even though the operations are largely successful, complications after joint replacement surgery occur frequently. Approximately 10% of lower limb arthroplasties need surgical revision, of which 70% are due to loosening. The purpose of this study was to assess the feasibility of 18-fluorodeoxyglucose positron emission tomography (18FFDG–PET) in detecting septic and aseptic endoprosthetic loosening of hip and knee endoprostheses.

Materials and Methods: Thirty-three patients (age range: 45–90y) with lower limb arthroplasty complaints (74 prostheses) were studied preoperatively with 18F-FDG-PET. All patients underwent surgery at a later stage with microbiological culturing to differentiate aseptic and septic loosening and to confirm the final diagnosis. Prostheses were tested intraoperatively for stability and microbiology.

Results: The sensitivity/specificity of 18F-FDG-PET towards implant loosening in the hip was 80%/87%, in the knee 56%/82%.

The sensitivity/specificity for infectious loosening in hip replacement arthroplasties was 67%/83%, in the knee 14%/89%.

Discussion: 18F-FDG-PET seems an excellent method for detecting hip endoprosthetic loosening and a moderate tool to diagnose hip implant infection. It should not be seen as the method of choice to diagnose knee endoprosthetic loosening and infection.

Introduction: Arthroplasty plays a growing role in our society today. Due to scientific and medical progress there are an increasing number of viable candidates and the improvement of quality of life thereafter speaks for itself.

Even though the operations are largely successful, complications after joint replacement surgery occur frequently. Approximately 10% of lower limb arthroplasties need surgical revision, of which 70% are due to loosening. The purpose of this study was to assess the feasibility of 18-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) in detecting septic and aseptic endoprosthetic loosening of hip and knee endoprostheses.

Materials and Methods: Thirty-three patients (age range: 45 – 90y) with lower limb arthroplasty complaints (74 prostheses) were studied preoperatively with 18F-FDG-PET. All patients underwent surgery at a later stage with microbiological culturing to differentiate aseptic and septic loosening and to confirm the final diagnosis. Prostheses were tested intraoperatively for stability and microbiology.

Results: The sensitivity/specificity of 18F-FDG-PET towards implant loosening in the hip was 80%/87%, in the knee 56%/82%.

The sensitivity/specificity for infectious loosening in hip replacement arthroplasties was 67%/83%, in the knee 14%/89%.

Discussion: 18F-FDG-PET seems an excellent method for detecting hip endoprosthetic loosening and a moderate tool to diagnose hip implant infection. It should not be seen as the method of choice to diagnose knee endoprosthetic loosening and infection.

Introduction: Trauma surgeons are often less exposed to large caseloads of primary osteoarthritis, compared to purely “elective”orthopaedic surgeons. The experience in total knee arthroplasty is thereby markedly On the other hand, posttraumatic knee arthrosis is often accompanied by severe deformity and axis deviation. In theory, navigated arthroplasty can overcome some of the problems in this setting.

Aim: Evaluation of the navigated technique of total knee arthroplasty (TKA), including the technical difficulties, the learning curve and the feasibility in severe bony deformity. Setting is a level I trauma center. Study setup was prospective, follow up period on average 14.5 months (11–25 months).

Patients: Between 7/04–6/05 we treated 36 patients with arthritis of the knee related to trauma. 18 patients were male. Average age at TKA was 59 (32–77) years. On average patients had 2.83 previous operations.

Methods: The navigational system used is manufactured by PRAXIM (La Tronche/France). It uses infrared-tracking and bone-morphing software. The implant was a mobile bearing LCS knee (DePuy/USA). Follow up included radiographs, clinical examination and the knee society scores.

Results: In three cases the procedure was finished in a conventional technique, reasons were suspicion of the surgeon about the cuts recommended by the system, a missing femoral cut block and a broken screw of the tracker-fixation. There was no failure of the navigational system. There was a clear learning curve regarding procedure time. Preop mean extension deficit was improved from av. 7.1° (0–30°) to 1.67° (0°–10°) postop., flexion contracture improved from av. 95° to 103°. The combined knee society score (max. 200 pts) improved from 77 pts preop to 156 pts at follow up.

Conclusions: Navigated knee endoprosthesis is reliable tool for the trauma surgeon with few technical problems. Especially for surgeons with less experience in TKA, planning of implant size and position is very helpful. With posttraumatic deformity the surgeon can gain valuable information and assistance to improve alignment and ligamentous balancing.