Aims. This study uses prospective registry data to compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Methods. Data on adult patients who underwent arthroscopic labral debridement or repair between 1 January 2012 and 31 July 2019 were extracted from the UK Non-Arthroplasty Hip Registry. Patients who underwent microfracture, osteophyte excision, or a concurrent extra-articular procedure were excluded. The EuroQol five-dimension (EQ-5D) and International Hip Outcome Tool 12 (iHOT-12) questionnaires were collected preoperatively and at six and 12 months post-operatively. Due to concerns over differential questionnaire non-response between the two groups, a combination of random sampling, propensity score matching, and pooled multivariable linear regression models were employed to compare iHOT-12 improvement. Results. A total of 2,025 labral debridements (55%) and 1,659 labral repairs (45%) were identified. Both groups saw significant (p < 0.001) EQ-5D and iHOT-12 gain compared to preoperative scores at 12 months (iHOT-12 improvement: labral repair = +28.7 (95% confidence interval (CI) 26.4 to 30.9), labral debridement = +24.7 (95% CI 22.5 to 27.0)), however there was no significant difference between procedures after multivariable modelling. Overall, 66% of cases achieved the minimum clinically important difference (MCID) and 48% achieved substantial clinical benefit at 12 months. Conclusion. Both labral procedures were successful in significantly improving early functional outcome following hip arthroscopy, regardless of age or sex. Labral repair was associated with superior outcomes in univariable analysis, however there was no significant superiority demonstrated in the multivariable model. Level of evidence: III. Cite this article: Bone Jt Open 2022;3(4):291–301

Traditional mechanical debridement can only remove visibly infected tissue and is unable to completely clear all the biofilm that hides within muscle crevices and nerves. This study aims to determine the results of single-stage revision using noncontact low frequency ultrasonic debridement in treating chronic periprosthetic joint infections (PJI). A prospective study of consecutive patients requiring single-stage revision for chronic PJI was performed since August 2021. After mechanical debridement, an 8‑mm handheld non‑contact low‑frequency ultrasound probe was used for ultrasonic debridement at a frequency of (25±5) kHz and power of 90% for 5 minutes. Each ultrasound lasted 10 seconds with 3‑seconds intervals. The probe was repeatedly sonicated among all soft tissue and bsingle interface. The distal femoral canal and the posterior capsule of the knee were fully sonicated with a special right‑angle probe. Chemical debridement was then performed to irrigation the whole operative area. Recurrence of infection, culture results and number of colonies 24 hours after ultrasonic debridement were recorded. A total of 45 patients (25 hips and 20 knees) were included and 43 of them (95.6%) were free of infection at a mean follow-up time of 29 months (24 to 33). There were no intraoperative complications related to ultrasonic debridement (neurovascular and muscle injury, poor wound healing and fat liquefaction). The culture‑positive rate of wound liquid before ultrasonic debridement was 40.0% (18/45), which significantly increased to 75.6% (34/45) after ultrasonic debridement (P=0.001). The median number of colonies 24 hours after ultrasonic debridement was 2372 CFU/ml (310 to 4340 CFU/ml), which was significantly higher than that before debridement (307 CFU/ml; 10 to 980 CFU/ml) (P=0.000). Single-stage revision with non‑contact low‑frequency ultrasonic debridement can fully expose bacteria within biofilm, increase the efficacy of chemical debridement and lead to a favorable short‑term outcome without related complications

Aims. The duration of systemic antibiotic treatment following first-stage revision surgery for periprosthetic joint infection (PJI) after total hip arthroplasty (THA) is contentious. Our philosophy is to perform an aggressive debridement, and to use a high local concentration of targeted antibiotics in cement beads and systemic prophylactic antibiotics alone. The aim of this study was to assess the success of this philosophy in the management of PJI of the hip using our two-stage protocol. Methods. The study involved a retrospective review of our prospectively collected database from which we identified all patients who underwent an intended two-stage revision for PJI of the hip. All patients had a diagnosis of PJI according to the major criteria of the Musculoskeletal Infection Society (MSIS) 2013, a minimum five-year follow-up, and were assessed using the MSIS working group outcome-reporting tool. The outcomes were grouped into ‘successful’ or ‘unsuccessful’. Results. A total of 299 two-stage revision THAs in 289 patients met the inclusion criteria, of whom 258 (86%) proceeded to second-stage surgery. Their mean age was 68.1 years (28 to 92). The median follow-up was 10.7 years (interquartile range (IQR) 6.3 to 15.0). A 91% success rate was seen in those patients who underwent reimplantation, decreasing to 86% when including those who did not proceed to reimplantation. The median duration of postoperative systemic antibiotics following the first stage was five days (IQR 5 to 9). There was no significant difference in outcome between those patients who were treated with antibiotics for ≤ 48 hours (p = 0.961) or ≤ five days (p = 0.376) compared with those who were treated with longer courses. Greater success rates were seen for Gram-positive PJIs (87%) than for Gram-negative (84%) and mixed-Gram PJIs (72%; p = 0.098). Conclusion. Aggressive surgical debridement with a high local concentration of targeted antibiotics at the time of first-stage revision surgery for PJI of the hip, without prolonged systemic antibiotics, provides a high rate of success, responsible antibiotic stewardship, and reduced hospital costs. Cite this article: Bone Joint J 2023;105-B(5):511–517

Introduction. Open and arthroscopic hip debridement may be used for treatment of femoral acetabular impingement (FAI). There is a paucity of evidence regarding the efficacy of one over the other. Aim. To compare survivorship in terms of further surgical procedure at five years, in patients having undergone either arthroscopic or open hip debridement. Methods. Using our institutional database, we identified all post learning curve arthroscopic and open hip debridement cases with five years of follow up. Patients were matched based on age, gender and Tonnis grade. The primary outcome measure was 5 year survivorship to total hip arthroplasty (THA). Secondary outcome measures included 5 year survivorship to further (non THA) procedures on the joint. Radiological parameters were analysed including femoral neck version, sourcil, centre-edge and alpha angles. Results. A total of 390 arthroscopic and 1316 open operations were identified. Following exclusion and matching 102 (62 female, 39 male) cases were available for analysis in each group. Mean age was 36 years (range 17–51). At 5 years 14.8% of arthroscopic debridement patients and 5.9% of open debridement patients had undergone THA (p =0 .038). There was no statistical difference in secondary outcome measures. Discussion. A significantly higher percentage of patients undergoing arthroscopic debridement went on to THA when compared to matched patients receiving open debridement. We acknowledge the limitations of this study. However, despite the increasing prevalence of arthroscopic surgery to treat FAI, our results would suggest that open debridement may still remain the gold standard intervention. Further investigation, ideally in the form of an RCT, is warranted. Conclusion. In our case matched series, despite the longer rehabilitation and greater soft tissue insult, open surgery for FAI was associated with significantly less patients progressing to THA within 5 years compared to those undergoing arthroscopic debridement

Objectives. The aim of this study was to use registry data to report and compare early patient outcomes following arthroscopic repair or debridement of the acetabular labrum. Methods. Data on adult patients who underwent arthroscopic labral debridement or repair between January 2012 and March 2019 was extracted from the UK Non-Arthroplasty Hip Registry dataset. Patients who underwent microfracture, osteophyte excision or a concurrent extra-articular procedure were excluded. Outcomes comprised EuroQol-5 Dimensions (EQ-5D) index and the International Hip Outcome Tool 12 (iHOT-12), preoperatively and at 6 and 12 months. Results. A total of 3,553 arthroscopies comprising 1,986 labral debridement (56%) and 1,567 labral repairs (44%) were identified. Both groups saw significant (p <0.0001) EQ-5D and iHOT-12 gain compared to pre-operative baseline scores at 6 months (iHOT-12: repair = +27.4 (95%CI 25.2 to 29.5), debridement = +24.8 (95%CI 22.7 to 26.9)) which was maintained at 12 months (repair = +28.3 (95%CI 26.0 to 30.6), debridement = +24.3 (95%CI 22.0 to 26.5)) with improvement being significantly greater in the repair group by 12 months (p = 0.016) including after modelling for patient and surgical factors. Overall, 64% of cases achieved the minimum clinically important difference (MCID) and 47% achieved substantial clinical benefit (SCB: repair = 51%, debridement = 43%, p = 0.005) at 12 months. Significant functional improvement was seen for both genders and in younger and older (>40 years) cohorts. Conclusion. Both labral repair and debridement techniques were successful in significantly improving 12-month outcomes following hip arthroscopy regardless of age or gender. Labral repair was associated with superior outcomes in comparison to debridement. Whilst patient selection is crucial, our findings support the repair of an injured labrum where possible. A multi-centre randomised controlled trial would be the most appropriate next step to overcome bias inherent in the existing literature

Aims. The aims of the study were to review and analyse the reported series of debridement, antibiotics and implant retention (DAIR) in the management of infected total hip arthroplasties (THAs) to establish the overall success and the influencing factors. Patients and methods. Using a standardised recognised study protocol, meta-analysis of observational studies in epidemiology guidelines, a comprehensive review and analysis of the literature was performed. The primary outcome measure was the success of treatment. The search strategy and inclusion criteria which involved an assessment of quality yielded 39 articles for analysis, which included 1296 patients. Results. The proportion of success following DAIR in the management of an infected THA appeared to improve after 2004 with a pooled mean proportion of success of 72.2%. For all reported series, from 1977 onwards, there was improved success with early debridement (< 7 days; 75.7%) and exchange of modular components (77.5%). There was a statistically non-significant improvement if debridement was performed within four weeks of the initial procedure (73.0%). Conclusion. The reported success following DAIR has improved since 2004. The only determinants of outcome which we found were the timing of debridement after the onset of symptoms of infection and the exchange of modular components. Cite this article: Bone Joint J 2017;99-B:1488–66

Background. The acetabular labrum provides sealing function and a degree of hip joint stability. Previous early(16 month) and mid-term(mean 3.5 years) follow-up of this cohort reported better patient related outcome measures in the refixation group. Methods. We reported patients who underwent labral debridement/focal labral excision during a period before the development of labral repair techniques. Patients with labral tears thought to be repairable with our current arthroscopic technique were compared with patients who underwent labral refixation. In 46 hips, the labrum was focally excised/debrided (group 1); in 54 hips, the labrum was refixed (group 2). Outcomes were measured with modified-Harris-Hip-Score (mHHS), Short Form-12 (SF-12), and a visual-analog-scale(VAS) for pain preoperatively and postoperatively. Results. Mean age was 33 years in group 1 and 28 years in group 2 with mean follow-up of 7 years (range, 2–13.6 years). At mean follow-up, subjective outcomes were significantly improved (P<.01) for both groups compared with preoperative scores. The mHHS (P=.005), SF-12 (P=.025), and VAS pain scores (P<.001) were all significantly better for refixation group compared with debridement group. Although most recent outcomes for both groups fell at mean 7 years' follow-up in comparison to 16 month and 3.5 year follow-up, the disparity between groups was greater in favor of labral refixation. Good-to-excellent results were 47.7% in debridement and 86.3% in refixation (p<.001), and failure rates were 29.6% (debridement) and 13.7% (refixation group) (p =.059). There were 4 revisions in the debridement group and 2 revisions in the refixation group. Conclusion. Longer term follow-up comparing focal labral debridement/excision to refixation revealed a decrease in patient related outcome scoring and good/excellent results in both groups. Ultimately, there was a greater drop in outcome measures and good/excellent results in the debridement group and better maintenance of results in the refixation group at mean 7 years follow-up. For any tables or figures, please contact the authors directly

We have reviewed the current literature to compare the results of surgery aimed to repair or debride a damaged acetabular labrum. We identified 28 studies to be included in the review containing a total of 1631 hips in 1609 patients. Of these studies 12 reported a mean rate of good results of 82% (from 67% to 100%) for labral debridement. Of the 16 studies that reported a combination of debridement and re-attachment, five reported a comparative outcome for the two methods, four reported better results with re-attachment and one study did not find any significant difference in outcomes. Due to the heterogeneity of the studies it was not possible to perform a meta-analysis or draw accurate conclusions. Confounding factors in the studies include selection bias, use of historical controls and high rates of loss of follow-up. It seems logical to repair an unstable tear in a good quality labrum with good potential to heal in order potentially to preserve its physiological function. A degenerative labrum on the other hand may be the source of discomfort and its preservation may result in persistent pain and the added risk of failure of re-attachment. The results of the present study do not support routine refixation for all labral tears. Cite this article: Bone Joint J 2014;96-B:24–30

Aims. To analyse the effectiveness of debridement and implant retention (DAIR) in patients with hip periprosthetic joint infection (PJI) and the relationship to patient characteristics. The outcome was evaluated in hips with confirmed PJI and a follow-up of not less than two years. Patients and Methods. Patients in whom DAIR was performed were identified from our hip arthroplasty register (between 2004 and 2013). Adherence to criteria for DAIR was assessed according to a previously published algorithm. Results. DAIR was performed as part of a curative procedure in 46 hips in 42 patients. The mean age was 73.2 years (44.6 to 87.7), including 20 women and 22 men. In 34 hips in 32 patients (73.9%), PJI was confirmed. In 12 hips, the criteria for PJI were not fulfilled and antibiotics stopped. In 41 (89.1%) of all hips and in 32 (94.1%) of the confirmed PJIs, all criteria for DAIR were fulfilled. In patients with exogenous PJI, DAIR was performed not more than three days after referral. In haematogenous infections, the duration of symptoms did not exceed 21 days. In 28 hips, a single debridement and in six hips two surgical debridements were required. In 28 (87.5%) of 32 patients, the total treatment duration was three months. Failure was noted in three hips (9%). Long-term follow-up results (mean 4.0 years, 1.4 to 10) were available in 30 of 34 (88.2%) confirmed PJIs. The overall successful outcome rate was 91% in 34 hips, and 90% in 30 hips with long-term follow-up results. . Conclusion. Prompt surgical treatment with DAIR, following strict diagnostic and therapeutic criteria, in patients with suspected periprosthetic joint infection, can lead to high rates of success in eradicating the infection. Cite this article: Bone Joint J 2017;99-B:330–6

Aims. Failure of irrigation and debridement (I&D) for prosthetic joint infection (PJI) is influenced by numerous host, surgical, and pathogen-related factors. We aimed to develop and validate a practical, easy-to-use tool based on machine learning that may accurately predict outcome following I&D surgery taking into account the influence of numerous factors. Methods. This was an international, multicentre retrospective study of 1,174 revision total hip (THA) and knee arthroplasties (TKA) undergoing I&D for PJI between January 2005 and December 2017. PJI was defined using the Musculoskeletal Infection Society (MSIS) criteria. A total of 52 variables including demographics, comorbidities, and clinical and laboratory findings were evaluated using random forest machine learning analysis. The algorithm was then verified through cross-validation. Results. Of the 1,174 patients that were included in the study, 405 patients (34.5%) failed treatment. Using random forest analysis, an algorithm that provides the probability for failure for each specific patient was created. By order of importance, the ten most important variables associated with failure of I&D were serum CRP levels, positive blood cultures, indication for index arthroplasty other than osteoarthritis, not exchanging the modular components, use of immunosuppressive medication, late acute (haematogenous) infections, methicillin-resistant Staphylococcus aureus infection, overlying skin infection, polymicrobial infection, and older age. The algorithm had good discriminatory capability (area under the curve = 0.74). Cross-validation showed similar probabilities comparing predicted and observed failures indicating high accuracy of the model. Conclusion. This is the first study in the orthopaedic literature to use machine learning as a tool for predicting outcomes following I&D surgery. The developed algorithm provides the medical profession with a tool that can be employed in clinical decision-making and improve patient care. Future studies should aid in further validating this tool on additional cohorts. Cite this article: Bone Joint J 2020;102-B(7 Supple B):11–19

Introduction. Debridement, antibiotics, and implant retention (DAIR) for acute prosthetic hip infection is a popular low morbidity option despite less than optimal success rates. We theorized that the delay between DAIR and explantation in failed cases may complicate eradication due to biofilm maturation and entrenchment of bacteria in periprosthetic bone. We ask, what are the results of two-stage reimplantation after a failed DAIR versus an initial two-stage procedure?. Methods. 114 patients were treated with 2-stage exchange for periprosthetic hip infection. 65 were treated initially with a 2-stage exchange, while 49 underwent an antecedent DAIR prior to a 2-stage exchange. Patients were classified according to MSIS host criteria. Failure was defined as return to the OR for infection, a draining sinus, or systemic infection. Results. Treatment failure occurred in 42.9% (21 of 49) of patients treated with an antecedent DAIR. In contrast, treatment failure occurred in only 12.3% (8 of 65) of initial 2-stage procedures (p< 0.001). Relative Risk of return to the OR after a 2-stage reimplantation with an antecedent DAIR compared to initial resection was 4.52 (95% CI 1.71, 11.9). MSIS host grading was similar between groups and did not influence the rate of failure. The DAIR cohort had increased hospitalization length and greater number of operative procedures (p< 0.001). Conclusion. We have shown that if irrigation and debridement fails to treat acute prosthetic hip infection, subsequent attempts at two-stage reimplantation may be compromised. Additionally, in the antecedent DAIR group, the average number of infection-related procedures (5) was nearly twice that of those initially resected (2.7). This by nature implies a significantly greater burden to the patient and cost to the healthcare system

Introduction. Open hip debridement surgery has been used for treatment of femoral acetabular impingement pain for over ten years in our unit. While literature has reported promising short-term outcomes, longer term outcomes are more sparsely reported. Patients/Materials & Methods. Patients who had undergone this surgery were identified on our database. Electronic, radiographic and paper records were reviewed. Demographic data, radiological and operative findings were recorded. Patients underwent ten-year review with standardised AP hip radiographs, questionnaire, non-arthritic hip (NAHS), Oxford hip (OHS) and SF-12 scores. Results. A total of 1626 operations were identified of which 183 had reached the tenth anniversary of their surgery. There were 91 females and 92 males. The average age was 39. Kaplan-Meier analysis indicated an overall 78% survival at ten years. However, once the learning curve was accounted for, by excluding the first year's cohort of patients, the survival rate was 84% at 10 years. Those who underwent hip arthroplasty were older at initial surgery and had a higher Tonnis grade than those who survived. The majority failed within the first 2 years. Labral repair, restoration of a normal centre edge angle and adequate CAM correction were associated with better survival. In those whose hip survived, the average NAHS and OHS were 87 and 39 respectively. 15% required further non-arthroplasty surgery (scope/revision) and 51% underwent trochanteric screw removal. 89% of survivors deemed their surgery to have been worthwhile at ten year follow up. Discussion. These results represent the first cohorts of our patients to reach ten year follow up. The results represent a learning curve in patient selection. It is unsurprising that those with more arthritic change were more likely to fail. Conclusion. In patients with clearly defined CAM impingement without joint space narrowing and where successful resection of the CAM and restoration of a normal centre edge angle can be achieved open hip debridement remains an operation with worthwhile outcomes at ten years

The reported success rate after treatment with debridement, antibiotics and implant retention (DAIR) of hip prosthesis infections has been found variable. We evaluated all reoperations performed because of infection and reported to Swedish Hip Arthroplasty Register (SHAR) between 1999 and 2016. The analyses were separated into reoperations performed for the first time and those which had been preceded by at least one previous reoperation performed because of the same reason. The outcome was repeated reoperation performed because of infection. 1,882 were first-time procedures (Group I) and 2,275 had been preceded by at least one reoperation due to infection (Group II). Head and/or liner exchange had been performed in 47% of the cases in group I, and in 22% in Group II. The mean age varied between 70 and 71 years and there was a dominance of males in all groups (52–59%). Compared to all primary THR performed during this period (n=319,813) patients with inflammatory disease, idiopathic femoral head necrosis and sequel after childhood disease were overrepresented for this type of procedure. Between 1999 and 2016 the number of DAIR procedures increased from 29 to 383 per year corresponding to 21 and 72 % of all reoperations performed due to infection. In first time reoperations the survival was 74.5±3.1% if the head/liner had been exchanged and 46.2±3.2% if only irrigation and synovectomy had been performed. In patients reoperated at least one time previously due to infection the survival rates dropped to 68.6±4.6% and 34.5±2.4%. Compared to first time reoperation with exchange of femoral and/or liner, synovectomy and irrigation without exchange of any implant part(s) resulted in an almost tripled risk of a second reoperation due to same reason (Hazard Ratio: 2.8, 95% confidence interval: 2.4–3.3). In cases previously reoperated because of infection (Group II) exchange of head/liner and debridement had a 28% increased risk of failure compared to the corresponding first time reoperations (1.28 1.02–1.6). If none of the components were replaced in Group II, the risk ratio for a new failure increased almost 4 times (3.8 3.3–4.4). Presence of a cemented stem increased the risk for further reoperations due to infection (1.14 1.02–1.28), but not presence of a cemented cup (1.06 0.92–1.19). All hazard ratios were adjusted for age, gender, diagnosis and type of fixation. The comparatively good results observed after exchange of head and liner might indicate that this is necessary to perform a sufficiently radical debridement. This observation could also be biased by a surgeon related factor suggesting that component exchange mainly is performed by surgeons with long experience of revision surgery

Introduction. We aim to evaluate the outcome of debridement and implant retention (DAIR) procedures performed for primary total hip prosthetic joint infections (PJI) and to identify factors correlating with a successful outcome. Methods. Patients were identified from theatre records. Electronic and paper notes were reviewed. Results. Fifty-four DAIR procedures for infected, elective, primary total hip replacements were performed between 2010 and 2017. Complete records were available for 44 procedures. There were 22 males and 22 females. Mean age was 71 (38–89) years. Mean follow-up was 21.6 (2–52) months. Ninety-one percent of DAIRs were performed for exogenous infections. Procedures were performed on average 23 days from the primary procedure in exogenous infections and 11 days from onset of symptoms in haematogenous infections. Nine of 40 cases for exogenous infection were performed more than 28 days from the primary procedure. The procedure resulted in a successful outcome in 34 cases (77%). There was no significant difference in the time to DAIR from the primary procedure comparing successful and unsuccessful cases. A successful outcome was associated with changing the femoral head, the procedure being performed by a revision hip surgeon, not inserting gentamicin impregnated fleece, and positive identification of the infecting organism. Discussion. Prompt treatment with DAIR of suspected primary hip PJI can result in a high rate of successful outcome. The femoral head should always be exchanged and a delay to DAIR is preferable to the procedure being performed by a surgeon who does not routinely perform revision hip surgery

The aims of the study were primarily to establish the overall success of debridement, antibiotics and implant retention (DAIR) in the management of infected total hip replacements (THRs) and secondarily to identify risk factors for failure. Using a standardised and recognised study protocol (“Meta-analysis of observational studies in epidemiology (MOOSE) guidelines) a systematic review and meta-analysis of the literature was performed. The primary outcome measure of interest was treatment success. The search strategy and inclusion criteria plus quality assessment yielded 39 articles eligible for analysis. The proportion of success from the literature following DAIR in the management of infected THRs is improving over time – the pooled mean proportion of success is 84.5% in studies from 2011–15. There was improved success with early debridement (75.7%) compared with delayed debridement (48.1%) (p=0.006). The reported outcomes following DAIR appear to be improving with time. One of the most influential determinants of outcome is timing of debridement from onset of symptoms. Surgeons should have a low threshold for investigating deep infection when presented with an acutely symptomatic THR and be aware of the updated reported outcomes associated with DAIR when considering management options

Femoroacetabular impingement is recognised as being a cause of labral tears and chondral damage. We report a series of five patients who presented with persistent pain in the hip after arthroscopy for isolated labral debridement. All five had a bony abnormality consistent with cam-type femoroacetabular impingement. They had a further operation to correct the abnormality by chondro-osteoplasty of the femoral head-neck junction. At a mean follow-up of 16.3 months (12 to 24) all had symptomatic improvement

Aims

Advocates of debridement, antibiotics and implant retention (DAIR) in hip periprosthetic joint infection (PJI) argue that a procedure not disturbing a sound prosthesis-bone interface is likely to lead to better survival and functional outcome compared with revision. This case-control study aims were to compare outcome of DAIRs for infected primary total hip arthroplasty (THA) with outcomes following primary THA and two-stage revision of infected primary THAs.

Introduction

The value of Debridement-Antibiotics-and-Implant-Retention (DAIR) in prosthetic-joint-infection (PJI) is still a matter of debate as most studies to-date are underpowered with variable end-points. In our, tertiary referral, bone infection unit we consider DAIR to be a suitable option in all PJIs with soundly fixed prostheses, despite chronicity. The aims of this study were to define the long-term outcome following DAIR in hip PJI and identify factors that influence it.

Ceramic-on-ceramic (CoC) articulations in total hip arthroplasty (THA) have low wear, but the unique risk of fracture. After revision for CoC fracture, ceramic third bodies can lead to runaway wear of cobalt chrome (CoCr) causing extremely elevated blood cobalt. We present five cases of ceramic liner fractures revised to a CoCr head associated with the rapid development of severe cobalt toxicity. We identified 5 cases of fractured CoC THA treated with revision to CoCr on highly cross-linked polyethylene (HXLPE) – three to conventional bearings and two to modular dual mobility bearings (CoCr acetabular liner, CoCr femoral head, and HXLPE). Mean follow up was 2.5 years after CoCr/HXLPE re-revision. Symptoms of cobalt toxicity occurred at average 9.5 months after revision for ceramic fracture (range 6–12). All patients developed vision and hearing loss, balance difficulties, and peripheral neuropathy. Several had cardiomyopathy, endocrinopathy, and local skin discoloration. Two reported hip pain. Re-revision for cobalt toxicity occurred at an average of 22 months (range 10–36) after revision for ceramic fracture. Average serum cobalt level at re-revision was 991 μg/L (range 734–1302, normal <1 μg/L). All CoCr heads exhibited massive wear with asphericity; deep tissues exhibited prominent metallosis. Treatment consisted of debridement and revision to a ceramic head with HXLPE. Serum cobalt improved to an average of 25 μg/L at final follow up. All patients reported partial improvement in vision and hearing; peripheral neuropathy and balance did not recover. Systemic cobalt toxicity is a rare but devastating complication of ceramic fracture in THA treated with cobalt-alloy bearings. Cobalt alloy bearings should be avoided in this setting. The diagnosis of systemic cobalt toxicity requires a high index of suspicion and was typically delayed following systemic symptoms. Debridement and revision to a ceramic-on-HXLPE leads to improvement but not resolution of cobalt toxicity complications

Aims. Hip arthroscopy (HA) has become the treatment of choice for femoroacetabular impingement (FAI). However, less favourable outcomes following arthroscopic surgery are expected in patients with severe chondral lesions. The aim of this study was to assess the outcomes of HA in patients with FAI and associated chondral lesions, classified according to the Outerbridge system. Methods. A systematic search was performed on four databases. Studies which involved HA as the primary management of FAI and reported on chondral lesions as classified according to the Outerbridge classification were included. The study was registered on PROSPERO. Demographic data, patient-reported outcome measures (PROMs), complications, and rates of conversion to total hip arthroplasty (THA) were collected. Results. A total of 24 studies were included with a total of 3,198 patients (3,233 hips). Patients had significantly less improvement in PROMs if they had Outerbridge grade III and IV lesions (p = 0.012). Compared with microfracture, autologous matrix-induced chondrogenesis (AMIC) resulted in significantly reduced rates of conversion to THA (p = 0.042) and of revision arthroscopy (p = 0.038). Chondral repair procedures in these patients also did not significantly reduce the rates of conversion to THA (p = 0.931), or of revision arthroscopy (p = 0.218). However, compared with microfracture, AMIC significantly reduced the rates of conversion to THA (p = 0.001) and of revision arthroscopy (p = 0.011) in these patients. Those with Outerbridge grade III and IV lesions also had significantly increased rates of conversion to THA (p = 0.029) and of revision arthroscopy (p = 0.023) if they had associated lesions of the acetabulum and femoral head. Those who underwent labral debridement had a significantly increased rate of conversion to THA compared with those who underwent labral repair (p = 0.015). Conclusion. There is universal improvement in PROMs following HA in patients with FAI and associated chondral lesions. However, those with Outerbridge grade III and IV lesions had significantly less improvement in PROMs and a significantly increased rate of conversion to THA than those with Outerbridge grade I and II. This suggests that the outcome of HA in patients with FAI and severe articular cartilage damage may not be favourable. Cite this article: Bone Joint J 2023;105-B(7):751–759