Investigation of the Actual Causes of Hip Joint Implant Loosening Classified as Aseptic--Analysis of Microbiological Culture Results and Levels of Inflammatory Markers.

Loosening of the hip joint prosthesis is considered as one of the most significant postoperative complications in recent years. The laboratory diagnostic procedure used to differentiate periprosthetic infection from aseptic loosening is very difficult because of the biofilm which microorganisms form on the implant surface. The purpose of this research was to evaluate the level of concordance between clinical classification of implant loosening among 50 patients subjected to reimplantation procedure and laboratory investigation of PJI including microbiological culture results and the levels of inflammatory markers assessed in the patients' synovial fluid samples, serum, and full blood. The synovial fluid was collected for leukocyte count, differential cell count, and culture on standard media. The levels of systemic inflammation markers such as the ESR and CRP concentration were determined in serum and full blood. Tissue samples were collected for microbiological studies. Components from endoprostheses were exposed to ultrasound in a process called sonication. Among the parameters measured in serum and full blood the levels of ESR and CRP were higher in the septic group of patients. Cytologic analysis of synovial fluid was in correlation with microbiologic identification. The most frequent isolated bacteria was Staphylococcus epidermidis. Culture results from materials such as synovial fluid, sonicate and tissues are crucial to establish the infectious aetiology of the loosening. Microscopic analysis of synovial fluid represents a simple, rapid and accurate method for differentiating PJI from aseptic failure. Sonication increases detection of the infectious process, and culture results are in correlation with the cytologic analysis of synovial fluid.

Sonication as a diagnostic approach used to investigate the infectious etiology of prosthetic hip joint loosening.

The purpose of the study was to evaluate the usefulness of sonication for the diagnosis of prosthetic joint infections (PJIs) by its comparison with periprosthetic tissues (PTs) and synovial fluid (SV-F) cultures. The study groups included 54 patients undergoing exchange of total hip prostheses for so called "aseptic" loosening occurring without clinical manifestations of an accompanying PJI and 22 patients who developed a sinus tract communicating with the prosthesis which was indicative of an ongoing infectious process. Significant positive culture results were obtained among 10 (18.5%) patients with "aseptic" implant failure and in 18 (81.8%) patients who developed a sinus tract. Sonicate-fluid (S-F) yielded bacterial growth in all culture-positive patients with "aseptic" loosening vs. 15 patients with presumed PJIs. There was a concordance in terms of bacterial species isolated from S-F and conventional cultures from individual patients. Coagulase-negative staphylococci were isolated most frequently. Sensitivity of sonication (75%) exceeded that estimated for PTs (69%) and SV-F (45%) cultures. We conclude that identification of causative agents of PJIs which is critical to further therapeutic decisions is aided by the combination of sonication and conventional culture.

Infectious prosthetic hip joint loosening: bacterial species involved in its aetiology and their antibiotic resistance profiles against antibiotics recommended for the therapy of implant-associated infections.

Reliable microbiological diagnosis along with surgery and prolonged antibiotic therapy are key elements in the management of prosthetic-joint infections (PJIs). The purpose of this study was to characterize antibiotic resistance profiles of bacteria involved in the aetiology of PJIs. A total of 33 bacterial isolates cultured from 31 patients undergoing exchange of total hip prostheses were analyzed. The diagnostic approach toward isolation of prosthesis- associated microorganisms included sonication of retrieved implants and conventional cultures of periprosthetic tissues and synovial fluid. The in vitro resistance profiles of bacterial isolates were determined in relation to antibiotics recommended for the therapy of PJIs using the disc diffusion method, E-tests(®) and broth microdilution system. Coagulase-negative staphylococci (CNS) were predominant microorganisms followed by Staphylococcus aureus, Enterobacter cloacae, Streptococcus mitis, and Propionibacterium acnes. Twenty out of 30 and 12 out of 30 staphylococcal isolates were methicillin- and multi-drug resistant, respectively. Only two isolates were rifampicinresistant. All staphylococci were susceptible to glycopeptides and linezolid. This paper stresses the pathogenic role of staphylococci in patients suffering from implant loosening and reports high methicillin- and multidrug-resistance rates in these bacteria. Hence, antimicrobial susceptibility tests of individual bacterial isolates must always be performed to guide selection of the optimal therapeutic option.

Characterization of Staphylococcus epidermidis and Staphyloccocus warneri small-colony variants associated with prosthetic-joint infections.

We determined the frequency of isolation of staphylococcal small-colony variants (SCVs) from 31 culture-positive patients undergoing revision of total hip prosthesis for aseptic loosening or presumed prosthetic-joint infection (PJI). We analysed auxotrophy of cultured SCVs, their antimicrobial susceptibility profiles and their biofilm-forming capacity. Eight SCV strains were cultivated from six (19 %) patients. All SCVs were coagulase-negative staphylococci (CNS) with Staphylococcus epidermidis as the predominant species; there was also one Staphylococcus warneri SCV. The SCVs were auxotrophic for haemin, with one strain additionally auxotrophic for menadione. We noted the presence of two phenotypically (differences concerning antimicrobial susceptibility) and genetically distinct SCV strains in one patient, as well as the growth of two genetically related SCVs that differed in terms of their morphology and the type of auxotrophy in another. Seven out of eight SCVs were resistant to meticillin and gentamicin. In addition, antibiotic sensitivity testing revealed three multidrug-resistant SCV-normal-morphology isolate pairs. One S. epidermidis SCV harboured icaADBC genes and was found to be a proficient biofilm producer. This paper highlights the involvement of CNS SCVs in the aetiology of PJIs, including what is believed to be the first report of a S. warneri SCV. These subpopulations must be actively sought in the routine diagnosis of implant-associated infections. Moreover, in view of the phenotypic and genetic diversity of some SCV pairs, particular attention should be paid to the investigation of all types of observed colony morphologies, and isolates should be subjected to antimicrobial susceptibility testing.

The mechanical and histological estimation of calcaneal tendon callus in rats after PRP injection.

BACKGROUND: The study investigated the potential impact of platelet-rich plasma on tendon healing. MATERIAL/METHODS: The study was conducted in 88 young, sexually mature rats, Wistar strain. The animals were randomly divided into two groups. The animals from the examined group (n=44) with an operated calcaneal tendon were given subcutaneously allogeneic PRP. The animals from the control group (n=44) were given 0.9% NaCl solution within the area of calcaneal tendon damage. After 7, 14, 21, and 42 days, the tendons were tested mechanically using the universal testing machines (UTM, Lloyd LRX), and were subjected to histological evaluation. RESULTS: The study evaluated the maximum breaking force (Fmax), the force at the end of the proportional range (Fs) and stiffness of the tendons (H). After 7 days of the experiment, there were significant differences in H (P=0.021), between the examined and control groups. There were no significant differences in Fmax (P=0.53) and Fs (P=0.48) after 7 days. Mean values of Fmax, Fs and H after 14, 21, and 42 days in the study group were significantly higher compared to the control group (P<0.05). In the histological evaluation, the tendons of the examined groups were characterized by higher cellular and vascular density and a more orderly arrangement of collagen fibers compared to the control groups. CONCLUSIONS: Growth factors in allogeneic PRP increased the mechanical strength of regenerating calcaneal tendons after 14, 21, and 42 days from injury. PRP resulted in the increased histological maturity of the tendon callus in examined groups, at each stage of the experiment.

[Results of operative treatment thoraco-lumbar fractures by posterior lumbar interbody fusion, Daniaux reconstruction or combination of both methods]. / Wyniki operacyjnego leczenia zlaman kregoslupa piersiowego i ledzwiowego tylna spondylodeza miedzytrzonowa, rekonstrukcja trzonu wedlug Daniaux oraz obiema metodami równoczesnie.

The aim of the study was to compare clinical and radiological results of treatment thoraco-lumbar spine fractures by short segment transpedicular stabilization accompanied by three techniques of reconstruction: posterior lumbar interbody fusion, vertebral body Daniaux reconstruction and combination of both methods. AO system was used to classify the fractures. Frankel's grade system was used for assessment of neurological deficit on admission and subsequently in the postoperative and follow-up period. The height of the fractured vertebral body and angle of segmental kyphotic deformation was measured on lateral X-ray pre- and post-operatively and at last follow-up. To the retrospective analysis we included 167 patients operated in the Orthopaedic and Traumatology Department, Medical University of Lublin in years 1998-2007. Posterior lumbar interbody fusion was performed in 69 patients (41%), isolated vertebral body Daniaux reconstruction in 82 patients (49%) and combination of both methods was performed in 16 patients (10%). The follow-up period has ranged from 3 to 13 years (mean 6.9 years). The most common type of the fracture was a B type (104 patients -62%), followed by type A (43 patients--26%), and type C (20--patients 12%). The neurological deficit was present in 80 patients. The postoperative neurological improvement was noticed in 37 patients (46%), whereas in 46 patients (54%) neurological status has not changed after the treatment. From 87 patients without neurological symptoms, we observed postoperatively contemporary neurological complications in 11 (12.6%) cases. The biggest correction of fractured vertebral height (mean 0.15) and correction of segmental kyphotic deformity (mean 6.3 degrees) we have noticed in the group of isolated vertebralbody Daniaux reconstruction with use of bone grafts. However in every group of patients we observed significant loss of correction during follow-up period. At the latest follow-up assessment there were no differences in vertebral body height of segmental kyphotic deformation between the analyzed groups of patients. None of analyzed methods of treatment: posterior lumbar interbody fusion, vertebral body Daniaux reconstruction or combination of these methods did not protect from recurrence of kyphotic deformity.

Bipolar cemented hip hemiarthroplasty in patients with femoral neck fracture who are on hemodialysis is associated with risk of stem migration.

BACKGROUND AND PURPOSE: Femoral neck fractures are considerably more common in patients on hemodialysis than in the general population. We determined the outcome of bipolar hemiarthroplasty for hip fracture in patients with long-term hemodialysis and compared it with that of a matched-paired group of patients with intact renal function. METHODS: We analyzed 26 bipolar hemiarthroplasties in 23 hemodialysed patients with a mean age of 56 (41-78) years who were followed for mean 3.6 (1-8) years. These cases were matched for age, sex, and BMI with 26 patients with femoral neck fractures and normal renal function. The mean follow-up time in the control group was 7 (5-10) years. As primary surgery for their femoral neck fracture, all patients had a bipolar hemiarthroplasty with a 28-mm metal-polyethylene internal articulation and a cemented stem. RESULTS: The mortality rate was 21% in the hemodialysed group and 4% in the control group (p = 0.005). The bipolar head migrated in 1 patient in the hemodialysed group but in none of the patients in the case-matched group. In the hemodialysed group, 8 stems migrated and 3 of these were revised, whereas in the control group 3 stems migrated and 2 were revised. The stem migration in the hemodialysed group was not preceded by the development of osteolysis or radiolucent lines at the bone-cement interface. The cumulative survival for prosthesis migration as endpoint was 44% at 5 years in the hemodialysed group and 96% in the control group (p = 0.03). INTERPRETATION: The main mode of failure of cemented bipolar hemiarthroplasties in hemodialysed patients is stem migration, due to failure of the bone-cement interface.

[Chiari pelvic osteotomy in the treatment of hip dysplasia in adults]. / Osteotomia nadpanewkowa kosci biodrowej wedlug Chiariego w leczeniu nastepstw dysplazji biodra u osób doroslych.

INTRODUCTION: [corrected] The aim of the study is early results evaluation of Chiari pelvic osteotomy. MATERIALS AND METHODS: In the years 1997-2003 36 patients (26 women and 10 men) in the age from 16 to 50 years old were operated on because of hip joint dysplasia. The indications for operative treatment were: pain, age less than 50 years, insufficient femoral head coverage without evidence of arthritic changes on X-ray. RESULTS: There were no intraoperative and postoperative complications. Harris Hip Score improved from 85 points before operation (from 82 to 90 pts.) to 95 points (from 92 to 100 pts.) after operative treatment. There was pain relief in most of the patients after osteotomy. Osteotomy healing was seen on X-ray examination usually after 6-12 weeks in 33 patients. Delayed osteotomy union till 6th postoperative month without influence on clinical hip improvement was seen in 3 patients. The increase in Wiberg CE angle from average 17.2 degrees (from 3 to 33 degrees) before operation to 44.9 degrees (from 19 to 78 degrees) after operation was statistically significant p< 0.00045. There was no loss in osteotomy correction. CONCLUSION: Supraacetabular osteotomy decreases pain, and increases hip function. Improvement in hip biomechanics and increase in femoral head coverage may lead to decrease in development of hip joint arthritic changes and time preserve before total hip arthroplasty.

[Wear and periprosthetic osteolysis of modular, hemispheric acetabular cups]. / Zuzycie i osteoliza wokól modularnych, pólkulistych panewek stawu biodrowego.

Osteolysis associated with polyethylene wear has become one of the most prevalent complications associated with uncemented modular, hemispherical cups. Sixty-five consecutive total hip arthroplasties (ABG i, Howmedica, Stryker) were followed 6-12 years. Cumulative survivorship for the cup was 55.7% after 10 years. There were 20 cups revisions because of polyethylene wear and periprosthetic osteolysis (14 cups) or cup loosening (6 cups). Stability was assessed intraoperatively, 14 cups were revised, whereas 6 new polyethylene cups were cemented into stable metal-back of acetabular component. The average annual wear of revised cups was 0.32 mm. The annual wear of not revised cups was 0.12 mm. The differences were statistically significant (p = 0.002). The mean area of osteolysis was 472 mm2 (SD 257 mm2). There was no significant correlation between wear and area of osteolysis. There was significant correlation R = 0.54, p = 0.014) between time to revision and area of osteolysis. There were no significant differences of wear of polyethylene inlay or area of osteolysis between stable and unstable acetabular cups.

[Intramedullary locked nailing in the treatment of proximal femoral fractures]. / Leczenie zlaman blizszej czesci kosci udowej przy pomocy ryglowanych pretów sródszpikowych.

INTRODUCTION: The aim of the study is evaluation of results of operative treatment the proximal femoral fractures with intramedullary locked nailing. MATERIAL AND METHOD: In years 1996-2004 44 patients were treated because of proximal femoral fractures with closed reduction and stabilization with intramedullary locked nailing. There were 15 women and 29 men in average age 60 years (18-95 years). There were 2 femoral neck fractures and 42 peritrochanteric fractures. The fracture of femoral shaft in 2 patients accompanied the fracture of proximal part of femur. The morphology of fractures was estimated according to AO classification. Clinical results were evaluated with Harris hip score (HHS). RESULTS: The average follow up is 8 months (from 6 to 24 months). There was good reduction of 27 fractures on postoperative radiograms. The average 15 degrees of varus lack of reduction was noted in 17 peritrochanteric fractures (from l0 to 35 degrees). There were mainly 31.A.3 unstable fractures according to AO classification. 3 patients died during three postoperative months from causes not connected with operative treatment. 39 fractures united in the period from 10 to 16 weeks. Delayed union--after 6 months occurred in 2 persons. Fatigue fracture of intramedullary rods occurred to both of this patients. The average Harris Hip Score was 86 points (from 70 to 100 points) after union of fractures. CONCLUSIONS: (1) The use of intramedullary locked nailing in the treatment of fractures of proximal part of femur leads to union without additional immobilization. (2) Closed intramedullary locked nailing in the treatment of unstable intertrochanteric fractures is connected with the risk of varus malalignment of fragments, which does not delay union, but decreases functional outcome. (3) Proper operative technique decreases the number of intra- and postoperative complications.

Long-term outcome of scaphoid nonunion treated by the Matti-Russe operation.

Background. This article presents the results of scaphoid non-union treatment using the Matti-Russe operation. The long-term outcome was compared in patients with bone union and patients with persistent nonunion. Materials and methods. We analyzed 81 cases (80 men, 1 woman) retrospectively. The end point was bone union or persistence of non-union. A long-term follow-up examination was done in 21 patients, with a follow-up ranging from 2 to 27 years (mean 8.8 years). Grip strength was measured with a dynamometer, range of movement was assessed, and the PRWE and DASH scales were used. Radiograms were evaluated for bone union, presence of osteoarthritis and radiolunate angle. Results. Bone union was achieved in 53 patients, persistent nonunion was observed in 23 patients (5 patients presented inadequate data for valid analysis). The long-term outcome was analyzed in 21 patients (14 with bone union and 7 with persistent nonunion). Better results based on subjective patient-rated scales were noticed in the group of bone union (PRWE 14.8, DASH 43.1) than in the non-union group (PRWE 30, DASH 61.8). Grip strength and range of movement were similar. The mean radiolunate angle was 9.6 in the bone union group, and 17.9 in the non-union group. Conclusions. The non-union ratio after Matti-Russe surgery was 28%. Grip strength and range of movement were similar in both groups. The results of the PRWE and DASH scales suggest better clinical outcome in patients with bone union.

[Treatment of tibial shaft fractures by intramedullary locking nailing]. / Leczenie zlaman trzonów kosci goleni za pomoca sródszpikowych gwozdzi ryglowanych.

Authors analyzed consecutive series of 56 tibial shaft fractures (43 men and 13 women) treated by intramedullary locking nails in years 1993-2004. Age of patients ranged from 17 to 83 years (mean 38 years). The final result was analyzed in 51 patients (91%). The bone union was observed in 50 patients. Fractures united within 6 months in 45 patients (88%), between 8 and 15 months in 5 patients. Operative treatment of non-union was necessary in one patient. The fractures united in anatomical axis in 45 cases, small (less than 10 degrees) valgus deviation was noticed in four patients, whereas five patients with fractures localized in distal part of the tibia had 11-30 degrees valgus deviation. The limb length inequality more than 1 cm was noticed in one case. There was neither infection nor compartment syndrome. One patient died because of fatal pulmonary embolism.

[Dislocation-disassembly of bipolar hip arthroplasty--case report]. / Zwichniecie z rozlaczeniem elementów protezy bipolarnej stawu biodrowego--opis przypadku.

Bipolar hip arthroplasty dislocation is rare. A case of bipolar hip arthroplasty dislocation in patient treated because of femoral neck fracture was described. Patient had neurological problems. The arthroplasty was made with posterolateral approach. Disassembly of bipolar prosthesis occurred during closed reduction. Open reduction with bipolar head exchange was necessary. To avoid this complication reduction should be made in anesthesia with muscles relaxation.

Hip arthroplasty after treatment failure in intertrochanteric femoral fractures.

Background. Treatment failure in intertrochanteric fractures of the femur leads to pain and limitations of limb function. Methods of treatment allowing for union in order to preserve the proximal femur are undertaken in younger patients. Older patients who have poor quality bone stock and bone loss in the proximal femur are treated with hip arthroplasty. The aim of our study was to perform a long-range follow-up on patients treated with hip arthroplasty after failure of peritrochanteric fracture treatment. Material and methods. We studied 10 patients (6 men and 4 women, average age 61 years) seen after treatment failure in peritrochanteric fractures during the period 1998 - 2003 in the Orthopedics and Traumatology Departament at the Skubiszewski Medical University of Lublin. Seven patients were treated with hemiarthroplasty, and three with total hip replacement. Three long femoral stems were used. Results. One patent died in the early postoperative period. There were two dislocations of hip replacements. An increase in Harris Hip Score was noted, from an average 25 points preoperatively to an average 85 points in long-term follow-up. There was one revision arthroplasty due to breakage of the ceramic cup and head of a Mittelmeier prosthesis. Conclusions. Patients treated with hip arthroplasty after treatment failures in peritrochanteric fractures of the femur can achieve a pain-free hip and good limb function.

High osteolysis and revision rate with the hydroxyapatite-coated ABG hip prostheses: 65 hips in 56 young patients followed for 5-9 years.

BACKGROUND: There are few reports on the outcome of uncemented HA-coated cups in young patients. PATIENTS: I evaluated the 7-year (5-9) results of HA-coated hip prosthesis (ABG, Stryker) in a consecutive series of 65 primary arthroplasties on 56 patients (mean age 44 years). 2 patients were lost to follow-up and 3 died. RESULTS: The cumulative survival rate with revision for any reason as endpoint at 9 years was 98% (95% CI, 96-100) for the stem, 69% (61-77) for the acetabular metal backing, and 59% (50-67) for the polyethylene liner. 15 of 65 cups were revised on average 6 years after the primary operation and 3 more are planned. Revisions were done in 3 hips because of loosening and migration of the cup, and in 12 hips because of wear and progressive osteolysis around stable components. Only hips with migration had clinical symptoms. Visual inspection of polyethylene liners revealed wear of the articulation in all cases, loosening of the locking mechanism in 10 cases and nonarticular surface deformity in 7 hips. All original stems are in situ although femoral osteolysis was seen in 12 cases and 1 hip was reoperated because of periprosthetic traumatic fracture. Despite the high revision rate, the clinical improvement was good: the average pre- and postoperative Harris Hip Scores at the most recent follow-up were 41 and 90, respectively. INTERPRETATION: While the results on the femoral side were good, the survival rates of the acetabular cups were poor and we stopped using ABG I hip prostheses.

Periprosthetic fractures of the femur after total hip arthroplasty: etiology and outcome.

Background. This article reports on our experience in the management of periprosthetic fractures of the femur. Materials and methods. We studied 44 patients (39 women and 5 men) with periprosthetic fractures of the femur after total hip replacement (THR). The average age of the patients at the time of surgery was 68 (range 33-82). Femoral fractures had occurred 1-20 years after THR in 27 hips. Revision hip arthroplasty was associated with periprosthetic fracture in 14 hips. Three patients had primary THR complicated by intraoperative femoral periprosthetic fracture. The outcome measures were bone union, delayed union or any revision intervention. Results. Bone union was achieved in 42 cases (95%). Thirty-five patients were satisfied with the surgical results, seven were moderately satisfied. Two patients had non-union of the femoral shaft, necessitating another intervention. The mean Harris Hip Score after bone union was 84 points (range 58-97). Deviation of the femoral axis was observed in 4 cases, due to subsiding of polished cemented stems. There were no deep infections. Conclusions. Internal stabilization with plate and cables is the best option in the treatment of fractured femur around a stable stem. Ineffective stabilization due to the use of a plate that was not long enough resulted in union with angulation. Long polished stems tended to subside within the cement mantle.

The Burch-Schneider antiprotrusio cage in revision hip arthroplasty with acetabular bone defect.

Background. This article presents early outcome of revision hip arthroplasties with massive defects of acetabular bone stock using the Burch-Schneider (B-S) antiprotrusio cage. Materials and methods. We prospectively followed 28 hips in 27 patients (17 women and 10 men). The average age of the patients was 68 years (range 40-82). Follow-up ranged from 12 to 53 months (ave. 25 months). Combined bone loss (type III according to the AAOS classification) was the most common (75% of the patients). Bone grafts (morselized and solid) were used to reconstruct deficient acetabula in 25 hips. Results. The patients were satisfied with the surgical result. The mean Harris Hip Score increased 36 points one year after operation and reached 80 points (range 56-93). The antiprotrusio cages were stable in all hips, even in 4 cases of inferior flange malposition. We found no measurable implant migration or graft resorption in any patient. Postoperative dislocation occurred in 3 hips (11%), two of them developed recurrent dislocations. There were no deep infections. Conclusions. Acetabular reconstruction using the Burch-Schneider antiprotrusio cage can be successfully used in managing massive acetabular defects in revision hip arthroplasty. The cage provides the basis for bone repair and protects grafts from excessive stress. Postoperative dislocation is the most common complication.

[Polished stem displacement from a cement mantle--a case report]. / Wysuwanie polerowanego trzpienia protezy typu Exeter z mankietu cementowego--opis przypadku.

Dislocation is a possible complication after primary and revision hip arthroplasty. Closed reduction is the first treatment option. Displacement of polished Exeter stem from a cement mantle during closed reduction of dislocated hip after revision hip arthroplasty is described. The patient was re-operated, new non-polished stem was cemented without any further complications. Placement of the cement mantle over superior and lateral part of the stem may prevent such complication.

[Hip metallosis caused by wear of a TT-1 stem on a ceramic modular head hip prosthesis --case report]. / Metaloza biodra wskutek zuzycia metalowego stozka trzpienia protezy TT-1 przez ceramiczna glowe--opis przypadku.

The author presents a case of metal stem cone wear caused by a ceramic head. During revision hip arthroplasty procedure a new modular ceramic head was implanted in combination with a stable cemented TT-1 stem. 13 months after surgery the hip became symptomatic and 20 months after the procedure total loosening of the cup was observed. Wear of the stem cone was visible. During the next revision procedure all hip prosthesis elements were removed, soft tissue debridement was performed and a new cemented prosthesis was implanted. One year post-op the hip is pain free.