Aims. Reimers migration percentage (MP) is a key measure to inform decision-making around the management of hip displacement in cerebral palsy (CP). The aim of this study is to assess validity and inter- and intra-rater reliability of a novel method of measuring MP using a smart phone app (HipScreen (HS) app). Methods. A total of 20 pelvis radiographs (40 hips) were used to measure MP by using the HS app. Measurements were performed by five different members of the multidisciplinary team, with varying levels of expertise in MP measurement. The same measurements were repeated two weeks later. A senior orthopaedic surgeon measured the MP on picture archiving and communication system (PACS) as the gold standard and repeated the measurements using HS app. Pearson’s correlation coefficient (r) was used to compare PACS measurements and all HS app measurements and assess validity. Intraclass correlation coefficient (ICC) was used to assess intra- and inter-rater reliability. Results. All HS app measurements (from 5 raters at week 0 and week 2 and PACS rater) showed highly significant correlation with the PACS measurements (p < 0.001). Pearson’s correlation coefficient (r) was constantly over 0.9, suggesting high validity. Correlation of all HS app measures from different raters to each other was significant with r > 0.874 and p < 0.001, which also confirms high validity. Both inter- and intra-rater reliability were excellent with ICC > 0.9. In a 95% confidence interval for repeated measurements, the deviation of each specific measurement was less than 4% MP for single measurer and 5% for different measurers. Conclusion. The HS app provides a valid method to measure hip MP in CP, with excellent inter- and intra-rater reliability across different medical and allied health specialties. This can be used in hip surveillance programmes by interdisciplinary measurers. Cite this article: Bone Jt Open 2023;4(5):363–369

Aims. The liner design is a key determinant of the constraint of a reverse total shoulder arthroplasty (rTSA). The aim of this study was to compare the degree of constraint of rTSA liners between different implant systems. Methods. An implant company’s independent 3D shoulder arthroplasty planning software (mediCAD 3D shoulder v. 7.0, module v. 2.1.84.173.43) was used to determine the jump height of standard and constrained liners of different sizes (radius of curvature) of all available companies. The obtained parameters were used to calculate the stability ratio (degree of constraint) and angle of coverage (degree of glenosphere coverage by liner) of the different systems. Measurements were independently performed by two raters, and intraclass correlation coefficients were calculated to perform a reliability analysis. Additionally, measurements were compared with parameters provided by the companies themselves, when available, to ensure validity of the software-derived measurements. Results. There were variations in jump height between rTSA systems at a given size, resulting in large differences in stability ratio between systems. Standard liners exhibited a stability ratio range from 126% to 214% (mean 158% (SD 23%)) and constrained liners a range from 151% to 479% (mean 245% (SD 76%)). The angle of coverage showed a range from 103° to 130° (mean 115° (SD 7°)) for standard and a range from 113° to 156° (mean 133° (SD 11°)) for constrained liners. Four arthroplasty systems kept the stability ratio of standard liners constant (within 5%) across different sizes, while one system showed slight inconsistencies (within 10%), and ten arthroplasty systems showed large inconsistencies (range 11% to 28%). The stability ratio of constrained liners was consistent across different sizes in two arthroplasty systems and inconsistent in seven systems (range 18% to 106%). Conclusion. Large differences in jump height and resulting degree of constraint of rTSA liners were observed between different implant systems, and in many cases even within the same implant systems. While the immediate clinical effect remains unclear, in theory the degree of constraint of the liner plays an important role for the dislocation and notching risk of a rTSA system. Cite this article: Bone Jt Open 2024;5(10):818–824

Aims. The Exeter short stem was designed for patients with Dorr type A femora and short-term results are promising. The aim of this study was to evaluate the minimum five-year stem migration pattern of Exeter short stems in comparison with Exeter standard stems. Methods. In this case-control study, 25 patients (22 female) at mean age of 78 years (70 to 89) received cemented Exeter short stem (case group). Cases were selected based on Dorr type A femora and matched first by Dorr type A and then age to a control cohort of 21 patients (11 female) at mean age of 74 years (70 to 89) who received with cemented Exeter standard stems (control group). Preoperatively, all patients had primary hip osteoarthritis and no osteoporosis as confirmed by dual X-ray absorptiometry scanning. Patients were followed with radiostereometry for evaluation of stem migration (primary endpoint), evaluation of cement quality, and Oxford Hip Score. Measurements were taken preoperatively, and at three, 12, and 24 months and a minimum five-year follow-up. Results. At three months, subsidence of the short stem -0.87 mm (95% confidence interval (CI) -1.07 to -0.67) was lower compared to the standard stem -1.59 mm (95% CI -1.82 to -1.36; p < 0.001). Both stems continued a similar pattern of subsidence until five-year follow-up. At five-year follow-up, the short stem had subsided mean -1.67 mm (95% CI -1.98 to -1.36) compared to mean -2.67 mm (95% CI -3.03 to -2.32) for the standard stem (p < 0.001). Subsidence was not influenced by preoperative bone quality (osteopenia vs normal) or cement mantle thickness. Conclusion. The standard Exeter stem had more early subsidence compared with the short Exeter stem in patients with Dorr type A femora, but thereafter a similar migration pattern of subsidence until minimum five years follow-up. Both the standard and the short Exeter stems subside. The standard stem subsides more compared to the short stem in Dorr type A femurs. Subsidence of the Exeter stems was not affected by cement mantle thickness. Cite this article: Bone Jt Open 2023;4(7):507–515

Aims. The Patient-Reported Outcomes Measurement Information System (PROMIS) has demonstrated faster administration, lower burden of data capture and reduced floor and ceiling effects compared to traditional Patient Reported Outcomes Measurements (PROMs). We investigated the suitability of PROMIS Mobility score in assessing physical function in the sequelae of childhood hip disease. Methods. In all, 266 adolscents (aged ≥ 12 years) and adults were identified with a prior diagnosis of childhood hip disease (either Perthes’ disease (n = 232 (87.2%)) or Slipped Capital Femoral Epiphysis (n = 34 (12.8%)) with a mean age of 27.73 years (SD 12.24). Participants completed the PROMIS Mobility Computer Adaptive Test, the Non-Arthritic Hip Score (NAHS), EuroQol five-dimension five-level questionnaire, and the Numeric Pain Rating Scale. We investigated the correlation between the PROMIS Mobility and other tools to assess use in this population and any clustering of outcome scores. Results. There was a strong correlation between the PROMIS Mobility and other established PROMs; NAHS (rs = 0.79; p < 0.001). There was notable clustering in PROMIS at the upper end of the distribution score (42.5%), with less seen in the NAHS (20.3%). However, the clustering was broadly similar between PROMIS Mobility and the comparable domains of the NAHS; function (53.6%), and activity (35.0%). Conclusion. PROMIS Mobility strongly correlated with other tools demonstrating convergent construct validity. There was clustering of physical function scores at the upper end of the distributions, which may reflect truncation of the data caused by participants having excellent outcomes. There were elements of disease not captured within PROMIS Mobility alone, and difficulties in differentiating those with the highest levels of function. Cite this article: Bone Jt Open 2021;2(12):1089–1095

Objectives. It has been hypothesized that patellofemoral pain, a common knee condition in adolescents and young adults, may be a precursor of degenerative joint changes and may ultimately lead to patellofemoral osteoarthritis. Since both conditions share several mechanical disease characteristics, such as altered contact area between the femur and patella and increased joint stress, we investigated whether these conditions share similar and different shape characteristics of the patella compared with normal controls. Methods. This cross-sectional study compared three different study populations: 32 patellofemoral pain subjects (mean age, 32 years (22 to 45); 72% female); 56 isolated radiological patellofemoral osteoarthritis subjects (mean age, 54 years (44 to 58); 89% female); and 80 healthy control subjects (mean age, 52 years (44 to 58); 74% female). Measurements included questionnaires, and lateral and skyline radiographs of the knee. Two separate 30-point 2D statistical shape models of the patella were created from the lateral and skyline radiographs. A general linear model was used to test for differences in standardized shape modes (a specific shape variant of the patella) between patellofemoral osteoarthritis, patellofemoral pain, and controls, using Bonferroni correction and adjustment for body mass index and gender. Results. Five shape modes showed statistically significant differences between groups: skyline modes 1 (p < 0.001), 8 (p = 0.004), and 10 (p < 0.001); and lateral modes 5 (p = 0.002) and 7 (p = 0.002). Skyline mode 8 and lateral mode 5 were similar for patellofemoral osteoarthritis and patellofemoral pain populations, while being statistically significant different from the control group. Conclusion. Our results indicate that patellofemoral pain and patellofemoral osteoarthritis share similar shape characteristics, which are different from control subjects. These findings support the proposed continuum disease model of patellofemoral pain predisposing to the development of patellofemoral osteoarthritis. Cite this article: J. F. A. Eijkenboom, J. H. Waarsing, E. H. G. Oei, S. M. A. Bierma-Zeinstra, M. van Middelkoop. Is patellofemoral pain a precursor to osteoarthritis? Patellofemoral osteoarthritis and patellofemoral pain patients share aberrant patellar shape compared with healthy controls. Bone Joint Res 2018;7:541–547. DOI: 10.1302/2046-3758.79.BJR-2018-0112.R1

Aims

Hip disease is common in children with cerebral palsy (CP) and can decrease quality of life and function. Surveillance programmes exist to improve outcomes by treating hip disease at an early stage using radiological surveillance. However, studies and surveillance programmes report different radiological outcomes, making it difficult to compare. We aimed to identify the most important radiological measurements and develop a core measurement set (CMS) for clinical practice, research, and surveillance programmes.

Objectives. Meropenem may be an important drug in the treatment of open tibial fractures and chronic osteomyelitis. Therefore, the objective of this study was to describe meropenem pharmacokinetics in plasma, subcutaneous adipose tissue (SCT), and cancellous bone using microdialysis in a porcine model. Methods. Six female pigs were assigned to receive 1000 mg of meropenem intravenously over five minutes. Measurements of meropenem were obtained from plasma, SCT, and cancellous bone for eight hours thereafter. Microdialysis was applied for sampling in solid tissues. The meropenem concentrations were determined using ultra-high-performance liquid chromatography. Results. The penetration of meropenem into cancellous bone, expressed as the ratio of plasma to cancellous bone area under the concentration-curve from zero to the last measured value, was incomplete and delayed. The time with concentration above the minimal inhibitory concentration (T. >MIC. ), for an MIC of 0.5 μg/ml, was shorter for cancellous bone in comparison with both plasma and SCT. For MICs above 0.5 μg/ml, T. >MIC. in cancellous bone was only shorter than SCT. Considering an MIC of 4 μg/ml, no animals achieved the target of 40% T. >MIC. in plasma and cancellous bone, while less than 20% achieved it in SCT. Conclusion. The main finding of this study was short T. >MIC. in cancellous bone after intravenous administration of 1000 mg meropenem. Consequently, in order to achieve sufficient tissue concentration in the cases of open tibial fractures and chronic osteomyelitis, supplemental application of meropenem may be necessary. Cite this article: P. Hanberg, A. Lund, K. Søballe, M. Bue. Single-dose pharmacokinetics of meropenem in porcine cancellous bone determined by microdialysis: An animal study. Bone Joint Res 2019;8:342–348. DOI: 10.1302/2046-3758.87.BJR-2018-0308.R1

Aims

This study aimed to investigate the incidence of ≥ 5 mm asymmetry in lower and whole leg lengths (LLs) in patients with unilateral osteoarthritis (OA) secondary to developmental dysplasia of the hip (DDH-OA) and primary hip osteoarthritis (PHOA), and the relationship between lower and whole LL asymmetries and femoral length asymmetry.

Aims

The aim of this study was to investigate the association between fracture displacement and survivorship of the native hip joint without conversion to a total hip arthroplasty (THA), and to determine predictors for conversion to THA in patients treated nonoperatively for acetabular fractures.

Aims

The impact of a diaphyseal femoral deformity on knee alignment varies according to its severity and localization. The aims of this study were to determine a method of assessing the impact of diaphyseal femoral deformities on knee alignment for the varus knee, and to evaluate the reliability and the reproducibility of this method in a large cohort of osteoarthritic patients.

Aims

Optimal glenoid positioning in reverse shoulder arthroplasty (RSA) is crucial to provide impingement-free range of motion (ROM). Lateralization and inclination correction are not yet systematically used. Using planning software, we simulated the most used glenoid implant positions. The primary goal was to determine the configuration that delivers the best theoretical impingement-free ROM.

Aims

Leg length discrepancy (LLD) is a common pre- and postoperative issue in total hip arthroplasty (THA) patients. The conventional technique for measuring LLD has historically been on a non-weightbearing anteroposterior pelvic radiograph; however, this does not capture many potential sources of LLD. The aim of this study was to determine if long-limb EOS radiology can provide a more reproducible and holistic measurement of LLD.

Aims

Classifying trochlear dysplasia (TD) is useful to determine the treatment options for patients suffering from patellofemoral instability (PFI). There is no consensus on which classification system is more reliable and reproducible for the purpose of guiding clinicians’ management of PFI. There are also concerns about the validity of the Dejour Classification (DJC), which is the most widely used classification for TD, having only a fair reliability score. The Oswestry-Bristol Classification (OBC) is a recently proposed system of classification of TD, and the authors report a fair-to-good interobserver agreement and good-to-excellent intraobserver agreement in the assessment of TD. The aim of this study was to compare the reliability and reproducibility of these two classifications.

Aims

The objective of this study was to compare simulated range of motion (ROM) for reverse total shoulder arthroplasty (rTSA) with and without adjustment for scapulothoracic orientation in a global reference system. We hypothesized that values for simulated ROM in preoperative planning software with and without adjustment for scapulothoracic orientation would be significantly different.

Aims

Orthopaedic surgery uses many varied instruments with high-speed, high-impact, thermal energy and sometimes heavy instruments, all of which potentially result in aerosolization of contaminated blood, tissue, and bone, raising concerns for clinicians’ health. This study quantifies the aerosol exposure by measuring the number and size distribution of the particles reaching the lead surgeon during key orthopaedic operations.

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The aim of this study was to evaluate the suitability of the tapered cone stem in total hip arthroplasty (THA) in patients with excessive femoral anteversion and after femoral osteotomy.

Aims

In order to release the contracture band completely without damaging normal tissues (such as the sciatic nerve) in the surgical treatment of gluteal muscle contracture (GMC), we tried to display the relationship between normal tissue and contracture bands by magnetic resonance neurography (MRN) images, and to predesign a minimally invasive surgery based on the MRN images in advance.

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The management of periprosthetic joint infection (PJI) remains a major challenge in orthopaedic surgery. In this study, we aimed to characterize the local bone microstructure and metabolism in a clinical cohort of patients with chronic PJI.

Aims

The survival of humeral hemiarthroplasties in patients with relatively intact glenoid cartilage could theoretically be extended by minimizing the associated postoperative glenoid erosion. Ceramic has gained attention as an alternative to metal as a material for hemiarthroplasties because of its superior tribological properties. The aim of this study was to assess the in vitro wear performance of ceramic and metal humeral hemiarthroplasties on natural glenoids.