A retrospective study on flap complications after pressure ulcer surgery in spinal cord-injured patients.

STUDY DESIGN: A retrospective study reporting specific complications of certain skin flaps for treating pressure ulcers. OBJECTIVES: To describe the rate and type of complications after pressure ulcer surgery in patients with spinal cord injury. SETTING: Germany, Rheinland Pfalz. METHODS: We collected data from 352 patients treated with 421 skin flaps to determine the rate and type of complications of each skin flap used. RESULTS: In this study, we analyzed the results of 421 skin flaps in 352 patients with a total of 657 pressure ulcers from January 2006 to December 2010. Our patients had ischial, pelvic, sacral, trochanteric and lower extremity ulcers. Ischial ulcers were most common, followed by sacral and trochanteric ulcers. There were 87 complications in 421 flaps, which was an overall rate of 21%. Suture line dehiscence was the most common complication with 27 cases (31%), followed by 22 cases of infection (25.2%), 17 cases of hematoma (19.5%), 12 cases of partial necrosis (13.7%) and 9 cases of total flap necrosis (10.3%). CONCLUSION: Pressure ulcers in spinal cord-injured patients are very common and difficult and expensive to treat. The high rate of complications and the associated costs suggest the importance of evaluating the efficacy of treatment options. Conservative procedures have been standardized, but there still has been limited success in establishing guidelines on how to manage complications arising from flap surgery. Our extensive documentation of flap plastics will be useful managing complications after the surgical treatment of pressure ulcers in spinal cord-injured patients.

[Outpatient surgery in hospital. An instrument for resource optimization?]. / Ambulante Chirurgie am Krankenhaus. Ein Instrument zur Belegungssteuerung?

The societies of western countries are facing enormous economic and social challenges. Despite a declining population size the number of elderly patients is growing and will lead to an increase in cases of trauma in the near future. In addition, the health care system will have to be financed by a reduced labor force. To realize the ambitious political goal of providing comprehensive medical care an economization of hospital treatment must be achieved. The bottleneck within the surgical specialties in case of efficient scheduling will be the capacity utilization of the operating theatres. Additional separate outpatient operating theatres adjacent to hospitals could be an efficient instrument for using resources and economizing medical procedures. Considering the socio-demographic alterations of our society an adequate discussion regarding the general medical conditions is essential.

[The cemented MS-30 stem. A multi-surgeon series of 333 consecutive cases]. / Der zementierte MS-30-Schaft : Ergebnisse einer Multi-surgeon-Serie von 333 konsekutiven Fällen.

INTRODUCTION: So far there is only one peer-reviewed long-term publication from the inventors' clinic for the MS-30 stem. MATERIAL AND METHODS: In a retrospective study we followed the first 333 consecutive MS-30 stems. All patients with 5- to 11-year follow-up were clinically and radiographically evaluated. At the time of implantation the criteria of modern cementing techniques were not implemented. Clinical evaluation was done using the scores of Harris and Merle d'Aubigné and Postel. Radiographic evaluation included quality of the cement mantle (true lateral radiographs taken under fluoroscopy), stem subsidence, loosening signs, and the risk for pending failure. RESULTS: At follow-up 12 hips had undergone femoral revision: 3 for aseptic loosening, 6 for infection, 1 for periprosthetic fracture, and 2 for recurrent dislocation. The overall survival for all reasons at 10 years was 96.1%; survival with aseptic loosening as an end point was 99.0%. The median Harris Hip Score at follow-up was 80 (26-100) points. Radiological evaluation revealed a thin cement mantle (<2 mm) in approximately 2/3, predominantly on the lateral views (Gruen zones 8/9). One-third of all reviewed prostheses were considered at risk for pending failure, which strongly correlated with the initial quality of the cement mantle. CONCLUSION: Midterm results with the MS-30 stem are encouraging and an even better long-term outcome can be expected with a better cement technique.

[Effect of femoral cementing technique on results. Comparison between retrograde technique and vacuum application]. / Einfluss der femoralen Zementiertechnik auf das Zementierergebnis. Vergleich von retrograder Technik und Vakuumapplikation.

METHODS: To evaluate the penetration depth of cement into trabecular femoral bone, femora of 14 sheep were subjected to simultaneous bilateral cementing. After femoral neck osteotomy, preparation of the bone cavities and jet lavage, cement was applied simultaneously using the conventional retrograde method for one side and vacuum application for the contralateral limb. Bilateral simultaneous pressurisation was then applied. All femoral specimens were X-rayed, sawed into standardised, horizontal, stereometric, identical slices and microradiographed. Cement penetration was assessed using a morphometric software system. RESULTS: No significant differences in depth of cement penetration between sheep femora cemented with the vacuum application method and the standard retrograde method could be found or between the ratio of cement-consolidated and non-cement-consolidated cancellous bone. CONCLUSION: The more complicated and technically challenging method of cement application under vacuum had no advantage in terms of cement interdigitation over the standard retrograde method.

[Integration of periosteum covered autogenous bone grafts with and without autologous chondrocytes. An animal experiment using the Göttinger minipig]. / Einwachsverhalten von periostgedeckten Knochendübeln mit und ohne autologe Knorpelzellen. Eine tierexperimentelle Untersuchung am Göttinger Minipig.

Autologous osteochondral transplantation has the major disadvantage of significant damage to a healthy joint surface at the donor site. The purpose of this study was to examine the effect of autogenous chondrocytes injected into the periosteum of autologous bone grafts in order to provide an alternative method for cartilage repair. A total of 22 Göttinger minipigs were operated twice on both knees. The first operation served for cartilage biopsy for the chondrocyte culture. During the second operation an osteochondral defect was created in the medial facet of the trochlear groove. The defect was treated differently with an autologous cortico-cancellous bone cylinder,harvested from the proximal tibia.Group A: untreated defect (control);B: bone-graft;C: bone-graft covered with periosteum; D: bone-graft with periosteum and injected autologous chondrocytes. The animals were killed after 6, 12, 26 and 52 weeks. The regenerated areas were evaluated macroscopically, tested biomechanically (long-term specimens; indentation-test) and a histological, blind evaluation was carried out according to a semi-quantitative scoring system. The periosteum covered bone cylinders in Groups C and D showed good repair of the bone and cartilage defect. The repaired tissue consisted predominantly of fibrocartilage with the partial formation of hyalin like tissue. The regenerated areas were integrated with the adjacent cartilage and were biomechanically superior when compared with the other groups. The additional injection of chondrocytes did not produce significantly better results. Our findings suggest that the transplantation of periosteum-covered bone cylinders may provide an alternative method for treating chondral and osteochondral defects and can be recommended for filling large donor site defects in joint surgery. The additional transplantation of chondrocytes does not seem to be justified.

[Significance of jet lavage for in vitro and in vivo cement penetration]. / Die Bedeutung der Jet-Lavage für das In-vitro- und In-vivo-Zementierergebnis.

AIM: The purpose of this study was to determine the efficacy of pulsatile jet lavage and manual syringe lavage with regard to their cleansing capabilities as measured by cement penetration into cancellous bone both in vivo and in vitro. METHODS: Three separate experiments were performed. Study A: In a cadaver study 36 left human cadaver femora were used for implantation of cemented femoral components. Conventional broaches were used for femoral preparation. Bone lavage was carried out either using jet lavage or manual syringe lavage of equal volume. The allocation to two different lavage groups was randomised. In both groups high-pressurising cementing techniques were implemented with the use of a proximal seal and additional finger packing. Study B: To guarantee standardised cement pressurisation and equal bone quality, the influence of jet lavage (1000 ml) versus syringe lavage (1000 ml) was studied in 11 paired human cadaver femora in an additional study without prosthesis implantation. The specimens were imbedded in specially designed pots. Bone cement was applied in a retrograde manner and subjected to a standard pressure protocol with a constant force of 3000 N. Study C: To directly compare the effectiveness of both pulsatile jet and syringe lavage with regard to cement penetration in vivo, a new sheep model allowing for standardised bilateral, simultaneous cement pressurisation was used. After femoral neck osteotomies both femoral cavities of 10 sheep were prepared for retrograde cement application. After randomisation one side was lavaged with 250 ml irrigation using a bladder syringe, the contralateral femur with the identical volume but using a pulsatile lavage. A specially designed apparatus was used to allow for bilateral simultaneous cement pressurisation. ANALYSIS: In all studies horizontal sections were obtained from the femoral specimens at predefined levels using a diamond saw. Microradiographs were taken and analysed using image analysis to assess cement penetration into cancellous bone. RESULTS: Study A: Compared with syringe lavage the use of jet lavage significantly improved the penetration of cement into cancellous bone (p = 0.027). In the presence of strong, dense cancellous bone the findings were more pronounced. Study B: Our results show that in equal quality bone, the use of jet lavage yields significantly (p < 0.001) improved cement penetration compared to syringe lavage specimens. Study C: The results of the in vivo study confirmed the superiority of jet lavage bone surface preparation (p = 0.002). CONCLUSIONS: The use of jet lavage yields significantly improved interdigitation between cancellous bone and cement both in vitro and in vivo and should be regarded as mandatory in cemented total hip arthroplasty. High pressurising techniques are effective means to improve cement penetration, but should only be administered with jet lavage to reduce the risk of fat embolism.

Lavage technique in total hip arthroplasty: jet lavage produces better cement penetration than syringe lavage in the proximal femur.

Sixteen paired human cadaver femora were prepared using conventional broaches. Cancellous bone was irrigated with 1 L pulsed lavage in one femur and 1 L syringe lavage in the contralateral femur. The specimens were embedded in specially designed pots, and vacuum-mixed bone-cements were applied in a retrograde manner. After application of a standard pressure to the pots, the femora were removed and radiographed, and horizontal sections were obtained and analyzed to assess cement penetration into cancellous bone and the ratio of the area of supported to unsupported cancellous bone (Rcb). Our results show that in equal quality bone, the use of jet lavage yields significantly (P < .0001) improved cement penetration and Rcb compared with syringe lavage specimens. Jet lavage should be considered routine to achieve interdigitation with cancellous bone in cemented total hip arthroplasty.

[Cemented hip prosthesis implantation--decreasing the rate of fat embolism with pulsed pressure lavage]. / Zementierte Hüftendoprothetik--Verminderung des Fettembolierisikos mittels gepulster Druckspülung.

Intraoperative fat embolism associated with cemented total hip arthroplasty is a well recognized complication. In a new sheep model allowing for standardized bilateral, simultaneous cement pressurization we studied the effectiveness of both pulsatile and syringe lavage of equal volume with regard to their cleansing capabilities as measured by fat and bone marrow intravasation. The operative procedure involved bilateral placement of intravenous catheters into the external iliac veins via retroperitoneal approach. After femoral neck osteotomies both femoral cavities were prepared for retrograde cement application. After randomization one side was lavaged with 250 ml irrigation using a bladder syringe, the contralateral femur with the identical volume but using a pulsatile lavage. A specially designed apparatus was used to allow for bilateral simultaneous cement pressurization. Venous blood from both iliac catheters was then collected, anticoagulated and a quantitative and qualitative fat analysis was performed. Despite equal volume manual lavage produced significantly higher fat and bone marrow intravasation (P < 0.001) than pulsatile lavage thus suggesting that not only the volume but also the quality of bone lavage is an essential factor influencing the risk of fat embolism and adverse cardiorespiratory effects. Our findings further emphasize the important role of pulsatile lavage in preventing fat and bone marrow embolisation during cemented total hip arthroplasty.