The Western Ontario Shoulder Instability Index (WOSI): validity, reliability, and responsiveness retested with a Swedish translation

Background and purpose The WOSI score questionnaire is a tool designed for self-assessment of shoulder function for patients with instability problems. We made a translation into Swedish and retested the score by analyzing the psychometric properties validity, reliability, and responsiveness

The Oswestry Disability Index.

STUDY DESIGN: The Oswestry Disability Index (ODI) has become one of the principal condition-specific outcome measures used in the management of spinal disorders. This review is based on publications using the ODI identified from the authors' personal databases, the Science Citation Index, and hand searches of Spine and current textbooks of spinal disorders. OBJECTIVES: To review the versions of this instrument, document methods by which it has been validated, collate data from scores found in normal and back pain populations, provide curves for power calculations in studies using the ODI, and maintain the ODI as a gold standard outcome measure. SUMMARY OF BACKGROUND DATA: It has now been 20 years since its original publication. More than 200 citations exist in the Science Citation Index. The authors have a large correspondence file relating to the ODI, that is cited in most of the large textbooks related to spinal disorders. METHODS: All the published versions of the questionnaire were identified. A systematic review of this literature was made. The various reports of validation were collated and related to a version. RESULTS: Four versions of the ODI are available in English and nine in other languages. Some published versions contain misprints, and many omit the scoring system. At least 114 studies contain usable data. These data provide both validation and standards for other users and indicate the power of the instrument for detecting change in sample populations. CONCLUSIONS: The ODI remains a valid and vigorous measure and has been a worthwhile outcome measure. The process of using the ODI is reviewed and should be the subject of further research. The receiver operating characteristics should be explored in a population with higher self-report disabilities. The behavior of the instrument is incompletely understood, particularly in sensitivity to real change

Can blood metal ion levels be used to identify patients with bilateral Birmingham Hip Resurfacings who are at risk of adverse reactions to metal debris?

AIMS: We investigated whether blood metal ion levels could effectively identify patients with bilateral Birmingham Hip Resurfacing (BHR) implants who have adverse reactions to metal debris (ARMD). PATIENTS AND METHODS: Metal ion levels in whole blood were measured in 185 patients with bilateral BHRs. Patients were divided into those with ARMD who either had undergone a revision for ARMD or had ARMD on imaging (n = 30), and those without ARMD (n = 155). Receiver operating characteristic analysis was used to determine the optimal thresholds of blood metal ion levels for identifying patients with ARMD. RESULTS: The maximum level of cobalt or chromium ions in the blood was the parameter which produced the highest area under the curve (91.0%). The optimal threshold for distinguishing between patients with and without ARMD was 5.5 µg/l (83.3% sensitivity, 88.4% specificity, 58.1% positive and 96.5% negative predictive values). Similar results were obtained in a subgroup of 111 patients who all underwent cross-sectional imaging. Between 3.2% and 4.3% of patients with ARMD were missed if United Kingdom (7 µg/l) and United States (10 µg/l) authority thresholds were used respectively, compared with 2.7% if our implant specific threshold was used, though these differences did not reach statistical significance (p ≥ 0.248). CONCLUSION: Patients with bilateral BHRs who have blood metal ion levels below our implant specific threshold were at low-risk of having ARMD. Cite this article: Bone Joint J 2016;98-B:1455-62

The effectiveness of blood metal ions in identifying patients with unilateral Birmingham hip resurfacing and Corail-Pinnacle metal-on-metal hip implants at risk of adverse reactions to metal debris.

Background We investigated whether blood metal ions could effectively identify patients with metal-on-metal hip implants with two common designs (Birmingham Hip Resurfacing [BHR] and Corail-Pinnacle) who were at risk of adverse reactions to metal debris. Methods This single-center, prospective study involved 598 patients with unilateral hip implants (309 patients with the BHR implant and 289 patients with the Corail-Pinnacle implant) undergoing whole blood metal ion sampling at a mean time of 6.9 years. Patients were classified into two groups, one that had adverse reactions to metal debris (those who had to undergo revision for adverse reactions to metal debris or those with adverse reactions to metal debris on imaging; n=46) and one that did not (n=552). Three metal ion parameters (cobalt, chromium, and cobalt-chromium ratio) were compared between groups. Optimal metal ion thresholds for identifying patients with adverse reactions to metal debris were determined using receiver operating characteristic analysis. Results All ion parameters were significantly higher (p &lt; 0.0001) in the patients who had adverse reactions to metal debris compared with those who did not. Cobalt maximized the area under the curve for patients with the BHR implant (90.5%) and those with the Corail-Pinnacle implant (79.6%). For patients with the BHR implant, the area under the curve for cobalt was significantly greater than that for the cobalt-chromium ratio (p=0.0005), but it was not significantly greater than that for chromium (p=0.8483). For the patients with the Corail-Pinnacle implant, the area under the curve for cobalt was significantly greater than that for chromium (p=0.0004), but it was similar to that for the cobalt-chromium ratio (p=0.8139). Optimal blood metal ion thresholds for identifying adverse reactions to metal debris varied between the two different implants. When using cobalt, the optimal threshold for identifying adverse reactions to metal debris was 2.15mg/L for the BHR group and 3.57mg/L for the Corail-Pinnacle group. These thresholds had good sensitivities (88.5% for the BHR group and 80.0% for the Corail-Pinnacle group) and specificities (84.5% for the BHR group and 76.2% for the Corail-Pinnacle group), high negative predictive values (98.8% for the BHR group and 98.1% for the Corail-Pinnacle group), and low positive predictive values (34.3% for the BHR group and 20.0% for the Corail-Pinnacle group). The authority thresholds proposed by the United States (3mg/L and 10mg/L) and the United Kingdom (7mg/L) missed more patients with adverse reactions to metal debris at 2.0% to 4.7% (twelve to twenty-eight patients) compared with our implant-specific thresholds at 1.2% (seven patients missed). Conclusions Patients who underwent metal-on-metal hip arthroplasty performed with unilateral BHR or Corail-Pinnacle implants and who had blood metal ions below our implant-specific thresholds were at low risk of adverse reactions to metal debris. These thresholds could be used to rationalize follow-up resources in asymptomatic patients. Analysis of cobalt alone is acceptable. Implant-specific thresholds were more effective than currently recommendedfixed authority thresholds for identifying patients at risk of adverse reactions to metal debris requiring further investigation.</p

Predicting high blood metal ion concentrations following hip resurfacing.

To determine whether gender, femoral head size, acetabular inclination, and time since surgery predicted high blood metal ion concentrations following Birmingham Hip Resurfacing (BHR).BHR patients with unilateral bearings at one specialist centre with blood cobalt and chromium concentrations measured up to May 2013 were included. This comprised a mixed (at-risk) group including symptomatic patients and asymptomatic individuals with specific clinical and/or radiological findings. Blood sampling was at a mean of 7.5 years (range 1-15.4 years) postoperatively.Of 319 patients (mean age 49.3 years; 53% male), blood metal ions greater than 7 µg/l were observed in 9% (n = 28). Blood metal ions were significantly higher in females (pandlt;0.001), femoral head sizes ≤48 mm (pandlt;0.01), and cup inclinations andgt;55° (pandlt;0.001). Linear regression demonstrated femoral head size was responsible for the highest proportion of variance in blood metal ions (cobalt pandlt;0.001, R2 = 8%; chromium pandlt;0.001, R2 = 11%). Analysis of femoral head size and inclination together demonstrated 36% of BHRs with head sizes of 38-44 mm and inclination andgt;55° had blood metal ions andgt;7 µg/l. BHR 10-year survival for this at-risk group was 91% (95% confidence intervals 86.0%-95.0%) with 30 hips revised.If blood metal ions are used to screen hip resurfacing patients for adverse reactions to metal debris it is recommended those with small femoral head sizes (38-44 mm) and high acetabular inclinations (andgt;55°) are targeted. These findings require validation in other cohorts as they may not be applicable to all hip resurfacing devices given the differences in radial clearance, coverage arc, and metallurgy