Background: Since Sir John Charnley introduced bio-clean air operating techniques such as the “body exhausting” system and a bio-clean air operating theatre to reduce the risk of infection 3), total hip replacement has become one of the safest and most successful procedures in orthopaedic surgery and has benefited numerous people suffering from arthritis all over the world. However, deep infection is still undoubtedly one of the most serious complications after total hip arthroplasty (THA). It is still controversial whether one or two stage revision should be indicated for deeply infected hip replacement.

Purpose: The aim of this study was to identify the influential factors in one stage revision THA for deep infection with a long-term follow-up.

Methods: One stage revision THA for deep infection was carried out in 273 joints on 262 patients by the senior author between 1974 and 2000. All infected hip replacements were primarily treated with one stage revision THA regardless of micro organisms at the authors’ unit as far as sufficient bone stock for socket fixation was available in the acetabulum. This study included 162 revisions in 154 patients for which a minimum follow-up of five years (range 5 to 28 years; average 12.3 years) had been done. Fifty-two cases (32.1 %) had had discharging sinus by the time of revision surgery for infection.

Results: One hundred and thirty eight (85.2 %) hips were free of infection at the time of the latest follow-up. Twenty cases (12.3 %) had reoperation for recurrent infection. Four hips (2.5 %) maintained their implants with the evidence of infection. Twenty-two cases (13.6 %) showed radiological loosening. Thirteen cases (8.0 %) were revised again for reasons other than infection (12 for aseptic loosening and one for dislocation). Bone stock did not have significant influence on infection control while it did affect mechanical outcome. The cement-bone interface was an affecting factor for not only the mechanical survival of implants but also the cure of infection. Neither discharging sinus nor gram-negative microorganism was considered as a contraindication.

Conclusion: This study presented the longest follow-up with a large number of cases in revision THA for deep infection. The results suggested that shielding medullary space with antibiotic-loaded cement was important for treatment of infected THA.

Purpose Coagulase negative staphylococci (CNS) have been one of the major pathogens responsible for prosthetic joint infections, and are showing increasing multiple-antibiotics resistance. Intact cell mass spectrometry (ICMS), based on the analysis of bacterial surface proteins, has been recognised as a new technique for identification of micro-organisms. The aim of this study was to evaluate the ability of ICMS for species level identification of clinical CNS isolates.

Method A total of 50 CNS strains from revision joint replacement operations were studied. ICMS and commercial identification kits were used for identification of those CNS. The commercial kits were used following the manufacturer’s recommendations. For ICMS, single colonies were smeared onto five spots on a sample slide. After drying, a 1 μl of aliquot of matrix solution was added to each spot. Analysis of strains was performed using a Kompact MALDI 2 linear, time of flight mass spectrometer and 3-ns pulse width nitrogen laser light. Combined spectra were constructed from 100 shots at each spot on the sample slide.

Results In this study, the commercial kit did not require any special equipment, but required overnight incubation and could not identify at least seven strains. On the other hand, the ICMS method was rapid, accurate and highly reproducible. The mass: charge spectra produced by ICMS contained potential biomarker peaks that could be used for species level identification.

Conclusions ICMS has the potential as a powerful tool for species level identification of clinical CNS isolates in terms of rapidity, accuracy and cost effectiveness. This study suggested that ICMS is a possible new method of identifying causative organism in infected joint replacements.

Introduction. Preoperative bone stock and cement-bone interface in revision total hip replacement (THR) for deep infection have never been investigated while they are both well known to be important for mechanical outcome after revision THR for aseptic loosening.

Purpose. The purpose of this study was to assess pre-operative bone stock and immediate postoperative cement-bone interface as factors affecting infection control after one stage revision THR for deep infection.

Material and methods. This study included 115 cases which satisfied following conditions; a) One stage revision THRs for deep infection were carried out by a single surgeon. b) Follow-up of more than five years was done. Preoperative bone stock was classified into four grades (Grade 0: No bone loss, Grade 1: Demarcation, Grade 2: Localized cavitation, Grade 3: Extensive bone loss). Immediate postoperative cement-bone interface was also graded into four categories (Grade A: White-out, obscure interface, Grade B: Clear line, no measurable gap, Grade C: Gap within 1mm, Grade D: Gap more than 1mm). These two factors were analyzed in view of infection control after surgery.

Results. Preoperative bone stock did not show significant influence on infection control. Immediate postoperative cement-bone interface was an affecting factor for cure of infection.

Conclusion. There was a good chance of cure of infection even in cases with significant bone loss. Good cement fixation appeared to be important in view of infection control. The results suggested the importance of shielding of medullary space with antibiotic-loaded cement from infected joint space in revision THR for infection.

Introduction and Aims: The aim of this study was to evaluate the efficacy of one stage revision THA for deep infection with a long-term follow-up.

Method: One stage revision THA for deep infection was carried out in 273 joints on 262 patients by the senior author between 1974 and 2000. All infected hip replacements were primarily treated with one stage revision THA, regardless of microorganisms at the authors’ unit unless bone stock in the hips was too poor for implant fixation. This study included 162 revisions in 154 patients for which a minimum follow-up of five years (range 5.1 to 27.6 years; average 12.3 years) had been done. Fifty-two cases (32.1 %) had had discharging sinus by the time of revision surgery for infection.

Results: One hundred and thirty eight (85.2 %) hips were free of infection at the time of the latest follow-up. Twenty cases (12.3 %) had reoperation for recurrent infection. Four hips (2.5%) maintained their implants with the evidence of infection. Twenty-two cases (13.6 %) showed radiological loosening. Thirteen cases (8.0 %) were revised again for reasons other than infection (12 for aseptic loosening and one for dislocation).

Conclusion: Deep infection is one of the most serious complications after total hip arthroplasty (THA). This study presented the longest follow-up, with a large number of cases in revision THA for deep infection. The results suggested that one stage revision was an effective treatment for deep infection of hip arthroplasty.

Background: Dislocation after total hip replacement (THR) is a significant concern with the increased number of THR carried out all over the world, although there has been a substantial lack of information regarding revision THR for instability in literature.

Purpose: The purpose of this study was to evaluate the effectiveness of operative treatment for recurrent dislocation after THR.

Material and methods: One hundred and eleven cases were treated operatively for recurrent dislocation after THR by a senior author (BMW). Group A; 104 cases were operated with change of either or both of components, a socket and a stem. Twenty-two mm head was used in 90 cases (A-1), 32 mm head in twelve (A-2), and 36 mm head in two (A-3). Group B; only modular head was changed in one case. Group C; augmentation device was applied on a cup in six cases. The average follow-up period was 6.2 years (range, 1 to 21 years).

Results: Group A-1; twelve cases (13%) required further operations for instability (N=90). Group A-2; one case (8.3%) was converted to Girdle-Stone for recurrent dislocation (N=12). Group A-3; one of them was revised for periprosthetic fracture (N=2). Group B; the case survived at the follow-up of 3.3 years (N=1). Group C; two cases (33%) were revised for dislocation (N=6).

Conclusion: We reported the largest series of revision THR for recurrent dislocation by a single surgeon with a considerable length of follow-up periods. Revision THR with change of components was an effective treatment for recurrent dislocation after THR.