To report mid-term results of PJI treated with uncemented stems.

: 80 hips of PJI after THA were treated with uncemented stems from 01/1993 to 12/2012 and followed prospectively. Selection occurred for one- (n=27) or two-stage (n=53) exchange according to the Liestal algorithm. Surgical approaches were transfemoral (n=58), transgluteal (n=9) or transtrochanteric (n=13). A monoblock (Wagner SL, n=58) or modular (Revitan, n=22) revision stem was implanted. On the acetabular side 44 Müller rings, 33 Burch-Schneider cages (combined with a cemented PE-cup) and 3 press-fit cups were used. Kaplan-Meier survival was calculated for endpoints (a) persistence of infection, (b) septic/aseptic stem loosening. Radiographs were analysed for (a) subsidence, (b) distal stem integration, (c) changes in cortical thickness, (d) proximal femur restoration, (e) radiolucency around stem/cup.

Mean FU was 5.2 (2–15) years. PJI was eradicated in 77 of 80 hips (96%). 3 patients (all two-stage) had a treatment failure. 2 were treated successfully with an additional two-stage exchange. In the 3rd patient we were not able to control infection and exarticulation was performed. Furthermore, one stem was revised for aseptic loosening (5 years), 1 for a broken Wagner stem (7 years) and 1 for subsidence (8 months). Stem survival after 5 years was 93% (SD ±2.5 years). 2 cups were revised for aseptic loosening and 1 for recurrent dislocations. Subsidence ≥5mm was found in 6 hips and occurred always within 3 months after surgery independent of stem type (p=0.947) and approach (p=0.691). Proximal femoral remodelling after transfemoral approach was excellent or good in 71% (32 excellent, 9 good) with no difference between one-/two-stage exchanges (p=0.288). Initial distal stem integration was 65mm medial and 66mm lateral and increased to 8mm medial (p=0.716) and 10mm lateral (p<0.001). Cortical thickness was unchanged over the entire FU period (p=0.493). Radiolucencies were seen around 26 stems, only the stem revised after 5years was rated loose.

Eradication of PJI was high using our established protocol even with uncemented revision stems. Mid-term survival was independent from one-/two-stage revision and comparable to results for aseptic loosening revision.

Summary

Staphylococcus aureus isolates from Fracture fixation device related infections contained fewer isolates that form a strong biofilm in comparison with isolates from Prosthetic joint infections. Both orthopaedic implant related infection groups possessed fnbB and sdrE more frequently than the non-implant related infection groups.

Introduction: In treatment for prosthetic hip joint infection (PHJI), the advantages of a 1-stage exchange over the classic 2-stage approach are the lower morbidity and earlier rehabilitation. Secondly, a recently published treatment algorithm for PHJI using well-defined selection criteria for 1-stage exchange had a 85–100% rate of cure for infection. Patient satisfaction after hip surgery is highly influenced by the functional result. We hypothesized that in our used algorithm the functional and radiological outcomes after a 1-stage exchange due to an implant-associated infection would be similar to a matched control group of 1-stage exchange due to aseptic loosening.

Material and Methods: Twenty-two cases (21 patients), with PHJI according to a well-defined definition, after 1-stage exchange of the prosthesis strictly according to the algorithm, with index-surgery between april 1996 and october 2004, were included in the studygroup. Case-matching was performed with aseptic revised cases for previous surgery, type of implant, use of transfemoral osteotomy, Charnley score, duration of follow-up, age, and sex. Outcome measures were perioperatively complications, functional results (Harris hip score, limping, and use of walking support) at two years, and the occurrence of revision for any reason and radiological loosening at latest follow-up. All outcomes were compared between both groups and with the results of the two stage revisions in our cohort. Finally, the eradication of infection was scored.

Results: In 86% of the 1-stage group (n = 19) there was an event-free follow-up for ≥ 2 years. The mean Harris hip score was 84, the incidence of limping 20% and 10% required two crutches. Two stems were revised due to aseptic loosening. Both functional and radiological outcomes were not different from the matched control group.

In the 2-stage group (n = 50) results were lower but not significantly, with 80, 30% and 28% respectively, and 2 stems and 1 cup were revised due to aseptic loosening.

One case (after one stage) developed an infection with a different pathogen and one case (after two stage exchange) had a relaps of infection.

Conclusion: By using the identical surgical technique in both septic and aseptic revision hip surgery, functional results are comparable between groups. These results indicate that 1-stage exchange according to a strict algorithm leads to a successful outcome in both maintaining functional mobility and eradicating infection.

Based on the analysis of Rittmann and Matter the AO advocated to leave stable implants after osteosynthesis in place and to remove them only when a sufficient bridging of the fractured would have happened. In opposition it generally became accepted to remove instable implants to be replaced by an external fixateur. Using local antiseptics such as Lavasept (Willlenegger) and intravenous antibiotics efficient against the proven bacteria one was able to cure the infection. Additional measures of osteoinduction (mainly cancellous autograft and decortication) favoured bridging of the non-union area. With the help of callus distraction after segmental resection of dead bone areas using more sophisticated external fixateurs marvellous reconstructions of big bone areas became possible.

On the other hand we have to realize, that in the upper extremities external fixation is frequently a clumsy installation inhibiting function. Because of delay of union not unfrequently secondary stabilazation of non-union or refracture areas had to be stabilized with secondary internal fixation. This was possible because the infection was already cured.

The knowledge of implant related infection did learn us, that the elimination of bacteria linked to a biofilm, which are at rest, frequently are resistant against antibiotics otherwise successful against planctonic bacteria of the same species. Be it by higher concentrations, be it by the use of antibiotics efficient against resting bacteria such as Rifampin ant once other possibilities are developed to be able to treat infections even in presence of internal osteosyntheses. When the success rate of intramedullary nails as they were used by Klemm was distinctly lower compared with external fixateurs at that time, today it becomes possible to us internal fixation in infections with bacteria with a known antibiotic treatment in presence of implants. This opens important doors for the combination of internal fixation, vascular bone grafts and antibiotic treatment accelerating the treatment of infected non-union in adequate cases.Stepwise it became possible to get to better functional results within a shorter time in adequate cases.

The Liestal algorithmus for the treatment of infected total joint arthroplasties proposes the abovementioned three groups for revisions with exchange.

One stage exchange is executed in the presence of a adequate soft tissue situation and in absence of bacteria difficult to treat.

Two stage revision with spacer and a interval of 2–3 weeks until re-implantation is indicated in bad soft tissue situations

Two stage revision without spacer, a curative intravenous antibiotic treatment period of 6 weeks, a break of 2 weeks followed by reimplantation is indicated in the presence of bacteria difficult to treat.

All patients of group 1 and 2 were treated with antibiotics for 3 months – the first two weeks intravenous.

The ones of group 3 only, if during reimplantation positive tissue cultures were harvested.

We analysed 72 episodes of ITHA, 22 with 1-stage exchange, 29 with 2-stage exchange with spacer, 21 with 2-stage exchange without spacer. All 16 cases but 1 with bacteria difficult to treat were included in the last group. In this presentation only cases are included following the algorithm completely as published. All patient had an overall treatment with antibioticsIn all patients the index operation was done more than two years prior to the latest control. Two patients died shortly after the operation, the result remaining unknown. Another 3 died between 1 and two years after the operation. They were regarded as probably cured. Only one case of group 2 suffered of a relapse being caused by a coagulase negative staphylococcus being resistant against Rifampin. 2-stage exchange without spacer was then successful. One case of reinfection with another bacterium happened in the group 1.

Conclusion: This analysis is indicating, that the presented algorithm allows positive results regarding elimination in around 95% of the cases. Better results may be provable when basing on a larger number of patients. It seems, that the selection of so called “easier cases” for 1-stage exchange does not lead to a higher number of relapses and helps for an overall more economic way of treatment.

Introduction: The original Müller straight stem (MSS, Zimmer^®; Winterthur, Switzerland) is made out of CoNiCr and showed excellent 20 year results but later modifications of the stem proved to be inferior. Aim of this study was to analyse the effect of shape, material and surface roughness on aseptic loosening of cemented Müller type straight stems.

Materials and patients: Between 1984 and 1996 a total of 926 THR were operated with four different versions of cemented Müller type straight stems and followed prospectively in the in-house register at our institution. Two different shapes of cemented Müller type straight stems (MSS and SL), both made out of two different alloys (CoNiCr and TiAl), were included in this study. All four versions differed in surface roughness (MSS CoNiCr Ra 1.0μm (satin); SL CoNiCr Ra 1.2μm (satin); MSS TiAl Ra 2.0μm (rough); SL TiAl Ra > 2.0μm (rough)). Survival analysis was done using Kaplan-Meier curves with aseptic loosening as endpoint, risk factors were tested with regression analysis.

Results: The 4 groups did not differ in age, gender and diagnosis, the mean follow up was 11.4 (0.1 to 23.0) years. Survival with aseptic loosening as endpoint was 97.7% (MSS CoNiCr), 96.4% (SL CoNiCr), 82.5% (MSS TiAl) and 67.4% (SL TiAl), respectively, at ten years. At final follow up all four groups differed significantly (p=0.044 Log rank test). Increasing roughness increased the risk for aseptic loosening and the harder CoCr had better survival than TiAl. results were significantly worse for the combination of the soft TiAl with a rough surface (SL TiAL, Ra > 2.0μm). For both stem designs the MSS shape had better survival than the SL shape (p=0.001)

Discussion: Wear modalities (abrasion vs. fretting) in the cement-stem interface are directly correlated with surface roughness, the amount of the released particles correlates with loosening. All examined stems had a roughness exceeding the limit of Ra =0.4 μm, producing abrasive wear with a higher volume of wear particles as compared to established polished stems which show fretting wear. Stem roughness and hardness are more important for long-term survival than some modifications in the shape.

Conclusion: Cemented Müller type straight stems should have a polished surface (Ra < 0.4 μm) and be made out of a hard material (CoNiCr) to minimize surface wear. This might be true for all types of cemented stems.

Introduction: Changes of the proximal femur like oste-olysis, stress shielding and osteopenia are frequently observed after total hip arthroplasty (THA). Such find-ings might be considered as risk factors for aseptic loosening and later revision. Cortical thinning is observed of healthy femora too and it is questioned whether the effect of the implant can be discriminated from age-related changes.

Aim of our study was to analyze cortical bone changes in prosthetic hips with time and compare those changes with the contra lateral non operated femur.

Materials and Methods:From 1984–87 165 hips were operated with a cemented Muller straight stem. Regular clinical and radiological follow up was scheduled after 1, 2, 5, 10, 15 years. We included only patients operated for osteoarthritis without revision and complete follow-up of more than 10 years. 37 THA hips in 35 patients remained for inclusion in the study. The mean follow-up was 16±4,6 years. Thickness of cortices was measured medially and laterally in 6 locations according to the 2nd to 6th Gruen zones and mean cortical thinning was calculated. The measurements were taken on standardized anterior-posterior x-rays of the pelvis. All measurements were analyzed with Image Access 4 Software calibrated with the reference to 32 mm femoral head.

10 patients were not operated on the contralateral hip and were measured in standardized manner in the same locations as in THA femurs.

Results: All included patients had pain free hips and did not require revision surgery at the last follow-up. Mean cortical thinning was 0,17±0,15 mm/year and it was mostly expressed in mid part of the stem (Gruen 2 and 6 zones). Most thinning occurred within the first 5 years (0,32±0,34 mm/year), later thinning was slower (0.09±0,37 mm/year). For the group with non operated contralateral hip mean thickness loss in THA hip was 0,2±0,17 mm/year and there was thickness loss of the contralateral femur too (0,03±0,12 mm/year), being much less as compared to the operated side (p< 0.001).

Conclusions: Loss of cortical thickness in THA hip with the Muller straight stem is frequently observed in long term and is not associated to expression of clinical symptoms and subsequent revision surgery. The effect is pronounced in the first postoperative years, mainly being explained by stress shielding. Additionally there is cortical thinning due to ageing, being much less than the influence of the implant. Thinning of the cortical bone must not be interpreted a sign of aseptic loosening.

Introduction: The Wagner SL Stem is a well established implant to bridge proximal femoral defects in hip revision surgery. The tapered shape offers the possibility of press-fit anchorage distal to the bone defect. There are missing long term results with absolute follow-up over ten years. The goal of the study was to observe the subsidence and the restoration of the proximal bony stock within ten years.

Patients and Methods: From 1988 until 2005 198 Wagner Stems were implanted in our hospital. 50% of the indications were due to aseptic loosening, 25 % due to septic loosening and 10% due to periprosthetic fracture and 15% other indications. Clinical function was measured with an adapted Harris Hip Score; subsidence was measured in the way that was previously described by Callaghan. The bony restoration was controlled with Böhm’s technique. The length and the thickness of the area of integration were measured in mm on the ap radiographs of the femur.

Results: The over all survival of the 198 Wagner stems after 17 years was 87%, for aseptic loosening. There were 57 implanted stems with ≥10 years follow-up. 31 of the patients died before the ten year control, four stems had to be exchanged because of aseptic loosening, three patients referred the clinical control so that a total number of 19 stems could be followed for at least 10 years. In two of those 19 stems there was significant subsidence (12 and 33mm), the subsidence occurred within the first year after implantation. The area of integration showed no change of length or thickness. The bony restoration was good or excellent in 70%. The adapted Harris Hip Score declined only little from 80 postoperatively to 75 after ten years.

Conclusion: No significant subsidence after Osteointegration occurred. The principle of the tapered stem is as good that the Wagner SL Stem can be widely indicated.

Introduction: Since its introduction in 1977 the Müller straight stem and its various copies have become one of the most often used cemented stems worldwide (about 1.1 million stems, figure quoted by manufacturer). Though, there is still a lack of long-term follow-up data.

Material/Methods: A consecutive series of 165 primary hip replacements (161 patients) with the original forged Müller straight stem (CoNiCr) was operated between July 1984 and June 1987 and followed prospectively. Mean age at operation was 68.9 years (25.6 to 86.3 years). 70 stems were implanted in female patients. Operation was done in supine position through a transgluteal approach with no trochanteric osteotomy. All stems were cemented with a second-generation technique (distal plug, cement syringe). The head diameter was 32 mm diameter, 134 heads were out of metal, 31 out of ceramic. 151 hips had a cemented polyethylene cup (52 with armament screws). 13 were combined with an acetabular reinforcement ring (Müller ring) and one with an anti-protrusion cage (Burch-Schneider).

Clinical and radiological follow-up was planned at 4 months 1, 2, 5, 10, 15 and 20 years. Clinical follow-up included a standardised examination and the completion of an IDES form. Cumulative survival rates were calculated by Kaplan-Meier analysis. Radiographs were analysed for osteolysis according to Gruen et al. (zones 1–7) and radiolucent lines.

Results: 3 patients (3 stems) were lost to follow-up (two postoperative and one after 16.8 years), 103 patients (with 106 hips) had died without revision and 55 patients (56 hips) remained for follow-up. 15 stems were revised, 11 for aseptic loosening (9 in combination with the cup), two for infection and two for other reasons. 13 further patients had isolated cup revision. Survival with aseptic loosening of the stem as endpoint was 86% (95%-CI: 82 to 90%) at 20 years.

The median HHS at the last follow-up was 80 points (range 30–98 points).

31% of the non-revised 41 stems showed osteolysis, most of them in zone 7 (21.9%). Two stems with isolated cup revision had a continuous radiolucent line. Incomplete radiolucent lines appeared most frequently in zone 1. Cup revision was associated with increased radiological changes on the femoral side (p=0.094, Mann-Whitney U-test).

Conclusion: The Müller straight stem shows excellent clinical and radiological results in the long-term, comparable to those achieved with other well established cemented and non-cemented stems. From our data further clinical use of the Muller straight stem can highly be recommended.

Introduction: The Acetabular Reinforcement Ring (ARR) (ME Müller®) was introduced in 1977 as successor of the Endler ring, especially to allow total hip replacement (THR) in patients with congenital hip dislocation, serious dysplasia and revision of loose cups. The Polyethylen (PE)-inlay can be freely oriented in the fixed ARR. It is the first implant with screws having angular stability as the screw-heads are blocked when cementing the inlay in the ring.

Patients and Methods: Out of 2251 primary THR performed between 1984 and 2005 at our hospital the ARR was used in 399 hips (363 patients). The indication for a THR with ARR was mainly a deficient acetabular bone stock as judged by the operating surgeon. 51 % of the patients had osteoarthritis, 22% dysplasia, 7% fractures, 6,5% osteonecrosis, 5% protrusion acetabuli, 4% rheumatoid arthritis and 4,5% other diagnosis. The mean age at operation was 66.4 years, 64% were females.

Intraoperatively, the ARR was placed with its medial border adjacent to the tear drop figure. The weight bearing area was fixed with 3–4 cancellous screws in the acetabular bone stock. Regular clinical and radiological follow-up 3months, 1, 2, 5, 10,15 and 20 years was planned. The radiographs were assessed for osteolysis, radiolucent lines and screw breakage after 15 years. Survival for revision due to aseptic loosening was calculated by Kaplan Meier.

Results: The overall survival regarding aseptic loosening of the cup was 100% after 10 years, 97,2% after 15 and 93,2% after 20 years.

Of the 96 patients (104 rings) operated at least 15 years ago, one was lost for follow-up. Three rings were revised due to aseptic loosening (11, 12, 16 years after implantation) and one was removed due to infection (1,8 years after implantation). 54 patients (with 56 rings) died before they reached the 15 years control. None of them was revised for aseptic loosening of the ring. 37 patients (43 hips) remained for 15-years control, six of them refused to come and were contacted by questionnaire or phone. Two cups were radiologically loose with broken screws but not symptomatic. The mean HHS after 15 years was 80.1.

Conclusion: The ARR shows a very good long term survival even in patients with difficult acetabular situations such as deficient bone stock. The design allows an application in a variety of positions. Even at a teaching hospital good long term results could be reached with this implant.

Introduction: The acetabular component in primary THA is placed on pathologic bone stock. Little is known about histology and its impact on aseptic cup loosening. We therefore investigated undecalcified acetabular bone biopsies taken prior to primary THA and at the time of revision surgery. Study design: In a prospective study, starting 01/1993, a bone biopsy of the acetabulum out of zone 1 according to De Lee and Charnley is taken in each primary THA in a standardized manner. In case of revision surgery of the cup, another biopsy is taken again. Between 01/1993 and 08/1997 351 cementless titanium shells with screws cups have been implanted at our institution. The average age at operation was 68 years (range 29–90 years). In 88% osteoarthritis was the primary diagnosis. Biopsies were classified as normal bone (type I), increased sclerosis (type II), restless bone (type III) or dead bone (type IV) according to a classification developed in our institution. Biopsies with a special entity such as rheumatoid arthritis are grouped «others». The initial diagnosis on the pre-operative X-ray was correlated to the results of the biopsies. Signs for aseptic loosening of the cup were defined on the complete x-ray series. All explanted cups were analysed for signs of impingement or increased wear.

Results: 8 cups (8 patients) had to be revised until August 2004 (average age at revision 63.6years, range 49.6–77.8 years). The initial diagnosis was osteoarthritis in 5 cases, twice avascular necrosis of the femoral head and 1 rheumatoid arthritis. 5 times we found metal-on-metal, 3 times PE-ceramic bearings. We found one of each biopsies in type I and type IV, 2 in type II and type III. 2 biopsies had to be grouped «others». At time of revision one biopsy initially grouped as type III had to be reclassified as «others». 2 cups were revised due to late haematogenous infection. 3 cases showed a direct relation between the result of the biopsy and failure of the cup. In 1 case we found surgical failure, though impingement and a type IV biopsy as combined reasons for failure. 2 cups (2 patients) revised after 1.2 years, immunhistological reaction due to metal-on-metal could have been the reason for failure (still under investigation).

Discussion: Surgical failures and implant related factors are accused as major reasons for loosening of the cup in THA, patient related factors often neglected. The acetabular bone quality, as one patient related factor, showed in almost half of the cases analysed a correlation with later acetabular loosening. One should therefore be aware of acetabular bone quality as one factor for loosening of the cup when monitoring acetabular implants, especially when newly introduced.

Introduction: The debris of standard Polyethylene in Total Hip Arthroplasty (THA) has been responsible for aseptic loosing and osteolysis in many patients. Wear rates for Polyethylene-Ceramic are analysed around 10 to 20 mm3 per year, those of PE-metal even 5 times more. Dislocation of primary THA is also common and problematic. Using a PE insert with a dorsal rim lowers the risk of dislocation but could be a potential risk for impingement if not correctly placed. Aim of this study was to value of reduced risk for dislocation in terms of increased risk for impingements. Study design: Between 1989 and 2003, 1107 non-cemented SL cups with Polyethylene on Ceramic were implanted in 953 patients, 422 (44%) implanted in women. All PE inserts were with dorsal rim. Average age at implantation was 69.9 years (range 39 to 90). In all cases, a cemented stem was implanted. Of those 1107 primary THA, 100 were revised for aseptic loosening. In 11 cases both components were revised, 7 times only the cup was replaced and for the 82 revisions remaining, only the stem was revised. In all cases the PE insert was removed and replaced. All inserts were analysed macroscopically for impingement and the volume worn off was calculated. Dislocation risk of PE couplings with rim was compared to standard PE couplings without rim. Results: In 18 PE inserts of 100 with rim, signs of impingement were found, ranging from slight (considered as creep not wear) to massive. An average yearly wear rate of 43 mm^3 (range 7 to 119) was calculated. Median survival time of the inserts without impingement was 5.2 years (range 0.7 to 11.4) of those with impingement it was reduced to 4.5 years (range 1.1 to 13.8). No statistical difference calculated (Mann-Whitney-U test, p=0.28) . In 2 of all 1107 cases (0.2%) operative revision of dislocation was performed whereas in 6 of the 598 cases (1%) with PE cups without rim, operative intervention was performed. Discussion: The use of a PE insert with dislocation protection rim holds a potential danger if not correctly placed. Though an earlier failing of THA with PE impingement was found, it was not significant and overpowered by the fact that most loosenings were due to cemented titanium stems with their great potential for early loosening.

Introduction: Polyethylene wear is an important factor for the longevity of total knee arthroplasty (TKA). One would expect that TKA lasting till death shows no or minimal wear compared to TKA undergoing revision surgery.

Material and Method: The present study retrospectively looks at the amount of front side wear on tibial retrievals and correlates clinical and radiological data sampled from these patients’ medical records. All Prostheses are of the same type and company (Stryker Howmedica, Allendale) with the following distribution: PCA 16, PCA modular 19 and Duracon 5. All inserts were gamma sterilized on air. Mean implantation time and mean age at implantation was 100.1 ±55.8 month and 70.7 ±7.4 years respectively. A modified visual score first described by Hood et al. 1983 served as measure for total damage on the polyethylene surface. Statistical Analysis was done by univariate analysis of variance.

Results: A highly significant influence on wear was found for the following factors: time of implantation (p< 0.001), kind of TKA design (p< 0.001), TKA belonging to the group of revision (0.016) and age at implantation (p< 0.021). A marginal influence was found for the factors: daily activity (p< 0.076) und kind of patella replacement (p< 0.085). Bodymass index and femorotibial axis had no measurable influence on wear.

Discussion: TKA retrieved at autopsy had and astonishingly high amount of wear. As a matter of fact none of the investigated implants was free of delamination, which is the most severe damage mode. In the present sample TKA design and time of implantation had a more important influence on wear than any other factor.

Introduction: Intramedullary reaming has its selected indication in osteomyelitis of long bones when remnants of dead infected bone are intramedullary embedded in a endostal new bone formation. The validity of this method has not yet been proven in long-term follow-ups. We reevaluated our patients in a 10 to 15 years follow-up to look at the recurrence rate of osteomyelitis after intramedullary reaming. We were also interested in the level of activity and the ability of working in our patients today.

Study design: From 1984 till 1992 forty-three patients with forty-four locations of chronic osteomyelitits of long bones were treated by intramedullary reaming. The collective consisted of 38 men and 5 women. The mean duration of the infection was 13.2 years. The causes of osteomyelitis were in 37 cases posttraumatic, in 6 cases haematogenous and one patient suffered from chronic osteomyelitis after removal of a total hip. Main locations of the focus were the diaphysis of the tibia and the femur. Intramedullary reaming was performed in patients with a infection centrally located in the bone protected by a thick periosteal new bone formation. In important endosteal bone formation a window was needed in order to pass with the guide wire for medullary reaming. Reaming went up to 18mm leaving a important cortical thickness of 6 to 10mm. Thorough irrigation focused a total removal of reaming mill. The treatment included a antibiotic therapy from 6 to 12 weeks. Staph. aureus was the most frequent micro-organism. The follow-up data was based on a continously documented clinical observation. Next to visits in our outpatient clinic we received informations by having designed a questionnaire booklet which was answered by the patients.

Results: In the 10 year follow-up in 37 cases (83%) osteomyelitis had never reoccurred. 5 patients needed a revision. 23 patients worked full-time, 3 had a reduced ability of work and 8 had been retired. 27 patients were pain-free, in 7 cases mild pain was found and 1 patient had moderate pain during working or walking. We have reevaluted 21 patients in a 15years follow-up, 7 patients will be followed up by 10/2004. Fifteen patients had died.

Discussion: Intramedullary reaming of the diaphysis of long bones after posttraumatic or haematogenous osteomyelitis proves to be a valuable treatment. The constitution of the bone, the reaming technique and the antibiotic therapy are influencing factors for a positive outcome.

Aims: Long-term quality assessment of intramedullary reaming of chronic osteomyelitis in long bones. Methods: Forty-three patients with forty-four chronic, consecutive, diaphysal osteomyelitis in long bones where treated by intramedullary reaming. Charts where retrospectively evaluated and a follow-up investigation took place. Results: The mean follow-up for thirty-four surviving patients was 117 months (84–178 months). At the follow-up, twenty-three patients work full-time, three have a reduced ability to work, and eight have retired. Twenty-seven patients have no pain, seven have mild pain, and one case has moderate pain during working or walking. Nine patients died during the follow-up. In thirty-seven cases (83%) osteomyelitis never reoccurred at the time of death or follow-up. Five patients needed revisions. One þstula closed spontaneously and one patient didnñt want a revision. Conclusions: The reaming technique as well as an interdisciplinary antibiotic therapy seems to inßuence the outcome. In attendance to the described technique, intramedullar reaming after post-traumatic or haematogenous osteomyelitis of the diaphysis of long bones proves to be a valuable treatment procedure with a local recurrence of 7% within þve years and 23% within fourteen years.

Aims: We have been alerted due to a high and early failure rate in total hip arthroplasties using metal-on-metal (Metasul?) bearings. Investigation on retrieved bearings at revision surgery should lead us to causes for early failures. Methods: 135 primary total hip arthroplasties in 118 patients (28 women and 90 men) with Metasul¨ bearing were implanted between 1992 and 1998. The mean age at implantation was 55 years (range, 29 to 84). In 105 cases a cementless MŸller SL cup and in 30 cases a MŸller Reinforcement Ring was used. Twelve out of 105 cases with a þne blasted SL cup needed a revision surgery after 34.9 months (range, 13 to 59). Qualitative histology was performed in all cases, quantitative metal analysis took place in two cases. The wear rate of the heads and their insert was measured and compared to former studies. Bony cylinders taken from the acetabular roof prior to primary implantation were histologically analyzed and compared to cup migration studies (EBRA). Results: Four cups and seven cemented titanium stems with tight cups were loose. In one case with polyarthritis both components had to be replaced. In one patient with cup loosening an impingement between neck and cup was found. In two patients histology showed diminution of bone-stock and in two cases no bony integration was observed. Conclusions: From twelve revision cases, we found only one where the metal-metal bearing is clearly responsible for the revision surgery. Metal-on-metal articulation seems to be promising if the component orientation is correct.