Aims. Femoral cement-in-cement revision is a well described technique to reduce morbidity and complications in hip revision surgery. Traditional techniques for septic revision of hip arthroplasty necessitate removal of all bone cement from the femur. In our two centres, we have been using a cement-in-cement technique, leaving the distal femoral bone cement in selected patients for septic hip revision surgery, both for single and the first of two-stage revision procedures. A prerequisite for adoption of this technique is that the surgeon considers the cement mantle to be intimately fixed to bone without an intervening membrane between cement and host bone. We aim to report our experience for this technique. Methods. We have analyzed patients undergoing this cement-in-cement technique for femoral revision in infection, and present a consecutive series of 89 patients. Follow-up was undertaken at a mean of 56.5 months (24.0 to 134.7) for the surviving cases. Results. Seven patients (7.9%) required further revision for infection. Ten patients died of causes unrelated to their infection before their two-year review (mean 5.9 months; 0.9 to 18.6). One patient was lost to follow-up at five months after surgery, and two patients died of causes unrelated to their hip shortly after their two-year review was due without attending. Of the remaining patients, 69 remained infection-free at final review. Radiological review confirms the mechanical success of the procedure as previously described in aseptic revision, and postoperative Oxford Hip Scores suggest satisfactory functional outcomes. Conclusion. In conclusion, we found that retaining a well-fixed femoral cement mantle in the presence of infection and undertaking a cement-in-cement revision was successful in 82 of the patients (92.1%) in our series of 89, both in terms of eradication of infection and component fixation. These results are comparable to other more invasive techniques and offer significant potential benefits to the patient. Cite this article: Bone Joint J 2022;104-B(2):212–220

Aims. Access to total knee arthroplasty (TKA) is sometimes restricted for patients with severe obesity (BMI ≥ 40 kg/m. 2. ). This study compares the cost per quality-adjusted life year (QALY) associated with TKA in patients with a BMI above and below 40 kg/m. 2. to examine whether this is supported. Methods. This single-centre study compared 169 consecutive patients with severe obesity (BMI ≥ 40 kg/m. 2. ) (mean age 65.2 years (40 to 87); mean BMI 44.2 kg/m. 2. (40 to 66); 129/169 female) undergoing unilateral TKA to a propensity score matched (age, sex, preoperative Oxford Knee Score (OKS)) cohort with a BMI < 40 kg/m. 2. in a 1:1 ratio. Demographic data, comorbidities, and complications to one year were recorded. Preoperative and one-year patient-reported outcome measures (PROMs) were completed: EuroQol five-dimension three-level questionnaire (EQ-5D-3L), OKS, pain, and satisfaction. Using national life expectancy data with obesity correction and the 2020 NHS National Tariff, QALYs (discounted at 3.5%), and direct medical costs accrued over a patient’s lifetime, were calculated. Probabilistic sensitivity analysis (PSA) was used to model variation in cost/QALY for each cohort across 1,000 simulations. Results. All PROMs improved significantly (p < 0.05) in both groups without differences between groups. Early complications were higher in BMI ≥ 40 kg/m. 2. : 34/169 versus 52/169 (p = 0.050). A total of 16 (9.5%) patients with a BMI ≥ 40 kg/m. 2. were readmitted within one year with six reoperations (3.6%) including three (1.2%) revisions for infection. Assuming reduced life expectancy in severe obesity and revision costs, TKA in patients with a BMI ≥ 40 kg/m. 2. costs a mean of £1,013/QALY (95% confidence interval £678 to 1,409) more over a lifetime than TKA in patients with BMI < 40 kg/m. 2. In PSA replicates, the maximum cost/QALY was £3,921 in patients with a BMI < 40 kg/m. 2. and £5,275 in patients with a BMI ≥ 40 kg/m. 2. . Conclusion. Higher complication rates following TKA in severely obese patients result in a lifetime cost/QALY that is £1,013 greater than that for patients with BMI < 40 kg/m. 2. , suggesting that TKA remains a cost-effective use of healthcare resources in severely obese patients where the surgeon considers it appropriate. Cite this article: Bone Joint J 2022;104-B(4):452–463

Aims. The aim of this study was to assess and compare active rotation of the forearm in normal subjects after the application of a short-arm cast (SAC) in the semisupination position and a long-arm cast (LAC) in the neutral position. A clinical study was also conducted to compare the functional outcomes of using a SAC in the semisupination position with those of using a LAC in the neutral position in patients who underwent arthroscopic triangular fibrocartilage complex (TFCC) foveal repair. Methods. A total of 40 healthy right-handed volunteers were recruited. Active pronation and supination of the forearm were measured in each subject using a goniometer. In the retrospective clinical study, 40 patients who underwent arthroscopic foveal repair were included. The wrist was immobilized postoperatively using a SAC in the semisupination position (approximately 45°) in 16 patients and a LAC in 24. Clinical outcomes were assessed using grip strength and patient-reported outcomes. The degree of disability caused by cast immobilization was also evaluated when the cast was removed. Results. Supination was significantly more restricted with LACs than with SACs in the semisupination position in male and female patients (p < 0.001 for both). However, pronation was significantly more restricted with SACs in the semisupination position than with LACs in female patients (p = 0.003) and was not significantly different in male patients (p = 0.090). In the clinical study, both groups showed improvement in all parameters with significant differences in grip strength, visual analogue scale scores for pain, modified Mayo Wrist Score, the Disability of the Arm, Shoulder, and Hand (DASH) score, and the Patient-Rated Wrist Evaluation (PRWE) score. No significant postoperative differences were noted between LACs and SACs in the semisupination position. However, the disability caused by immobilization in a cast was significantly higher in patients who had a LAC on the dominant hand (p < 0.001). Conclusion. We found that a SAC in the semisupination position is as effective as a LAC in restricting pronation of the forearm. In addition, postoperative immobilization with a SAC in the semisupination position resulted in comparable pain scores and functional outcomes to immobilization with a LAC after TFCC foveal repair, with less restriction of daily activities. Therefore, we recommend that surgeons consider using a SAC in the semisupination position for postoperative immobilization following TFCC foveal repair for dorsal instability of the distal radioulnar joint. Cite this article: Bone Joint J 2022;104-B(2):249–256

Aims. Our objective was to conduct a systematic review and meta-analysis, to establish whether differences arise in clinical outcomes between autologous and synthetic bone grafts in the operative management of tibial plateau fractures. Methods. A structured search of MEDLINE, EMBASE, the online archives of Bone & Joint Publishing, and CENTRAL databases from inception until 28 July 2021 was performed. Randomized, controlled, clinical trials that compared autologous and synthetic bone grafts in tibial plateau fractures were included. Preclinical studies, clinical studies in paediatric patients, pathological fractures, fracture nonunion, or chondral defects were excluded. Outcome data were assessed using the Risk of Bias 2 (ROB2) framework and synthesized in random-effect meta-analysis. The Preferred Reported Items for Systematic Review and Meta-Analyses guidance was followed throughout. Results. Six studies involving 353 fractures were identified from 3,078 records. Following ROB2 assessment, five studies (representing 338 fractures) were appropriate for meta-analysis. Primary outcomes showed non-significant reductions in articular depression at immediate postoperative (mean difference -0.45 mm, p = 0.25, 95%confidence interval (CI) -1.21 to 0.31, I. 2. = 0%) and long-term (> six months, standard mean difference -0.56, p = 0.09, 95% CI -1.20 to 0.08, I. 2. = 73%) follow-up in synthetic bone grafts. Secondary outcomes included mechanical alignment, limb functionality, and defect site pain at long-term follow-up, perioperative blood loss, duration of surgery, occurrence of surgical site infections, and secondary surgery. Mean blood loss was lower (90.08 ml, p < 0.001, 95% CI 41.49 to 138.67) and surgery was shorter (16.17 minutes, p = 0.04, 95% CI 0.39 to 31.94) in synthetic treatment groups. All other secondary measures were statistically comparable. Conclusion. All studies reported similar methodologies and patient populations; however, imprecision may have arisen through performance variation. These findings supersede previous literature and indicate that, despite perceived biological advantages, autologous bone grafting does not demonstrate superiority to synthetic grafts. When selecting a void filler, surgeons should consider patient comorbidity, environmental and societal factors in provision, and perioperative and postoperative care provision. Cite this article: Bone Jt Open 2022;3(3):218–228

Aims. There is evidence that morbidly obese patients have more intra- and postoperative complications and poorer outcomes when undergoing total hip arthroplasty (THA) with the direct anterior approach (DAA). The aim of this study was to determine the efficacy of DAA for THA, and compare the complications and outcomes of morbidly obese patients with nonobese patients. Methods. Morbidly obese patients (n = 86), with BMI ≥ 40 kg/m. 2. who underwent DAA THA at our institution between September 2010 and December 2017, were matched to 172 patients with BMI < 30 kg/m. 2. Data regarding demographics, set-up and operating time, blood loss, radiological assessment, Harris Hip Score (HHS), International Hip Outcome Tool (12-items), reoperation rate, and complications at two years postoperatively were retrospectively analyzed. Results. No significant differences in blood loss, intra- and postoperative complications, or implant position were observed between the two groups. Superficial wound infection rate was higher in the obese group (8.1%) compared to the nonobese group (1.2%) (p = 0.007) and relative risk of reoperation was 2.59 (95% confidence interval 0.68 to 9.91). One periprosthetic joint infection was reported in the obese group. Set-up time in the operating table and mean operating time were higher in morbidly obese patients. Functional outcomes and patient-related outcome measurements were superior in the obese group (mean increase of HHS was 52.19 (SD 5.95) vs 45.1 (SD 4.42); p < 0.001), and mean increase of International Hip Outcome Tool (12-items) was 56.8 (SD 8.88) versus 55.2 (SD 5.85); p = 0.041). Conclusion. Our results suggest that THA in morbidly obese patients can be safely and effectively performed via the DAA by experienced surgeons. Cite this article: Bone Jt Open 2022;3(1):4–11

Aims. Studies on long-term patient-reported outcomes after open surgery for triangular fibrocartilage complex (TFCC) are scarce. Surgeons and patients would benefit from self-reported outcome data on pain, function, complications, and satisfaction after this surgery to enhance shared decision-making. The aim of this study is to determine the long-term outcome of adults who had open surgery for the TFCC. Methods. A prospective cohort study that included patients with open surgery for the TFCC between December 2011 and September 2015. In September 2020, we sent these patients an additional follow-up questionnaire, including the Patient-Rated Wrist Evaluation (PRWE), to score satisfaction, complications, pain, and function. Results. A total of 113 patients were included in the analysis. At ≥ 60 months after an open TFCC reinsertion, we found a mean PRWE total score of 19 (SD 21), a mean PRWE pain score of 11 (SD 11), and a PRWE function score of 9 (SD 10). The percentage of patients obtaining minimum clinically important difference rose from 77% at 12 months to 83% at more than 60 months (p < 0.001). Patients reported fewer complications than surgeons, and overall complication rate was low. Conclusion. Outcomes of patient-reported pain, function scores, and satisfaction are improved five years after open surgery for the TFCC. Cite this article: Bone Jt Open 2021;2(11):981–987

Orthopaedics has been left behind in the worldwide drive towards diversity and inclusion. In the UK, only 7% of orthopaedic consultants are female. There is growing evidence that diversity increases innovation as well as patient outcomes. This paper has reviewed the literature to identify some of the common issues affecting female surgeons in orthopaedics, and ways in which we can address them: there is a wealth of evidence documenting the differences in the journey of men and women towards a consultant role. We also look at lessons learned from research in the business sector and the military. The ‘Hidden Curriculum’ is out of date and needs to enter the 21st century: microaggressions in the workplace must be challenged; we need to consider more flexible training options and support trainees who wish to become pregnant; mentors, both male and female, are imperative to provide support for trainees. The world has changed, and we need to consider how we can improve diversity to stay relevant and effective. Cite this article: Bone Jt Open 2021;2-10:893–899

Aims. Inadvertent soft tissue damage caused by the oscillating saw during total knee arthroplasty (TKA) occurs when the sawblade passes beyond the bony boundaries into the soft tissue. The primary objective of this study is to assess the risk of inadvertent soft tissue damage during jig-based TKA by evaluating the excursion of the oscillating saw past the bony boundaries. The second objective is the investigation of the relation between this excursion and the surgeon’s experience level. Methods. A conventional jig-based TKA procedure with medial parapatellar approach was performed on 12 cadaveric knees by three experienced surgeons and three residents. During the proximal tibial resection, the motion of the oscillating saw with respect to the tibia was recorded. The distance of the outer point of this cutting portion to the edge of the bone was defined as the excursion of the oscillating saw. The excursion of the sawblade was evaluated in six zones containing the following structures: medial collateral ligament (MCL), posteromedial corner (PMC), iliotibial band (ITB), lateral collateral ligament (LCL), popliteus tendon (PopT), and neurovascular bundle (NVB). Results. The mean 75. th. percentile value of the excursion of all cases was mean 2.8 mm (SD 2.9) for the MCL zone, mean 4.8 mm (SD 5.9) for the PMC zone, mean 3.4 mm (SD 2.0) for the ITB zone, mean 6.3 mm (SD 4.8) for the LCL zone, mean 4.9 mm (SD 5.7) for the PopT zone, and mean 6.1 mm (SD 3.9) for the NVB zone. Experienced surgeons had a significantly lower excursion than residents. Conclusion. This study showed that the oscillating saw significantly passes the edge of the bone during the tibial resection in TKA, even in experienced hands. While reported neurovascular complications in TKA are rare, direct injury to the capsule and stabilizing structures around the knee is a consequence of the use of a hand-held oscillating saw when making the tibial cut. Cite this article: Bone Joint J 2020;102-B(10):1324–1330

Aims. The purpose of this study was to compare the clinical, radiological, and patient-reported outcome measures (PROMs) in the first 100 consecutive patients undergoing total hip arthroplasty (THA) via a direct superior approach (DSA) with a matched group of patients undergoing THA by the same surgeon, using a posterolateral approach (PLA). Methods. This was a retrospective single surgeon study comparing the first 100 consecutive DSA THA patients with a matched group of patients using a standard PLA. Case notes were examined for patient demographics, length of hospital stay, operating time, intra- and postoperative complications, pain score, satisfaction score, and Oxford Hip Score (OHS). Leg length discrepancy and component positioning were measured from postoperative plain radiographs. Results. The DSA patients had a shorter length of hospital stay (mean 2.09 days (SD 1.20) DSA vs 2.74 days (SD 1.17) PLA; p < 0.001) and shorter time to discharge from the inpatient physiotherapy teams (mean 1.44 days (SD 1.17) DSA vs 1.93 days (SD 0.96) PLA; p < 0.001). There were no differences in operating time (p = 0.505), pain levels up to postoperative day 1 (p = 0.106 to p =0.242), OHS (p = 0.594 to p = 0.815), satisfaction levels (p = 0.066 to p = 0.299), stem alignment (p = 0.240), acetabular component inclination (p < 0.001) and anteversion (p < 0.001), or leg length discrepancy (p = 0.134). Conclusion. While the DSA appears safe and was not associated with a significant difference in PROMs, radiological findings, or intraoperative or postoperative complications, a randomized controlled trial with functional outcomes in the postoperative phase is needed to evaluate this surgical approach formally. Cite this article: Bone Joint J 2021;103-B(3):500–506

Aims. The aims of this study were to compare clinically relevant measurements of hip dysplasia on radiographs taken in the supine and standing position, and to compare Hip2Norm software and Picture Archiving and Communication System (PACS)-derived digital radiological measurements. Methods. Preoperative supine and standing radiographs of 36 consecutive patients (43 hips) who underwent periacetabular osteotomy surgery were retrospectively analyzed from a single-centre, two-surgeon cohort. Anterior coverage (AC), posterior coverage (PC), lateral centre-edge angle (LCEA), acetabular inclination (AI), sharp angle (SA), pelvic tilt (PT), retroversion index (RI), femoroepiphyseal acetabular roof (FEAR) index, femoroepiphyseal horizontal angle (FEHA), leg length discrepancy (LLD), and pelvic obliquity (PO) were analyzed using both Hip2Norm software and PACS-derived measurements where applicable. Results. Analysis of supine and standing radiographs resulted in significant variation for measurements of PT (p < 0.001) and AC (p = 0.005). The variation in PT correlated with the variation in AC in a limited number of patients (R. 2. = 0.378; p = 0.012). Conclusion. The significant variation in PT and AC between supine and standing radiographs suggests that it may benefit surgeons to have both radiographs when planning surgical correction of hip dysplasia. We also recommend using PACS-derived measurements of AI and SA due to the poor interobserver error on Hip2Norm. Cite this article: Bone Joint J 2021;103-B(11):1662–1668

Aims. The aim of this study was to determine if uncemented acetabular polyethylene (PE) liner geometry, and lip size, influenced the risk of revision for instability or loosening. Methods. A total of 202,511 primary total hip arthroplasties (THAs) with uncemented acetabular components were identified from the National Joint Registry (NJR) dataset between 2003 and 2017. The effect of liner geometry on the risk of revision for instability or loosening was investigated using competing risk regression analyses adjusting for age, sex, American Society of Anesthesiologists grade, indication, side, institution type, surgeon grade, surgical approach, head size, and polyethylene crosslinking. Stratified analyses by surgical approach were performed, including pairwise comparisons of liner geometries. Results. The distribution of liner geometries were neutral (39.4%; 79,822), 10° (34.5%; 69,894), 15° (21.6%; 43,722), offset reorientating (2.8%; 5705), offset neutral (0.9%; 1,767), and 20° (0.8%; 1,601). There were 690 (0.34%) revisions for instability. Compared to neutral liners, the adjusted subhazard ratios of revision for instability were: 10°, 0.64 (p < 0.001); 15°, 0.48 (p < 0.001); and offset reorientating, 1.6 (p = 0.010). No association was found with other geometries. 10° and 15° liners had a time-dependent lower risk of revision for instability within the first 1.2 years. In posterior approaches, 10° and 15° liners had a lower risk of revision for instability, with no significant difference between them. The protective effect of lipped over neutral liners was not observed in laterally approached THAs. There were 604 (0.3%) revisions for loosening, but no association between liner geometry and revision for loosening was found. Conclusion. This registry-based study confirms a lower risk of revision for instability in posterior approach THAs with 10° or 15° lipped liners compared to neutral liners, but no significant difference between these lip sizes. A higher revision risk is seen with offset reorientating liners. The benefit of lipped geometries against revision for instability was not seen in laterally approached THAs. Liner geometry does not seem to influence the risk of revision for loosening. Cite this article: Bone Joint J 2021;103-B(12):1774–1782

Aims. To determine if primary cemented acetabular component geometry (long posterior wall (LPW), hooded, or offset reorientating) influences the risk of revision total hip arthroplasty (THA) for instability or loosening. Methods. The National Joint Registry (NJR) dataset was analyzed for primary THAs performed between 2003 and 2017. A cohort of 224,874 cemented acetabular components were included. The effect of acetabular component geometry on the risk of revision for instability or for loosening was investigated using log-binomial regression adjusting for age, sex, American Society of Anesthesiologists grade, indication, side, institution type, operating surgeon grade, surgical approach, polyethylene crosslinking, and prosthetic head size. A competing risk survival analysis was performed with the competing risks being revision for other indications or death. Results. The distribution of acetabular component geometries was: LPW 81.2%; hooded 18.7%; and offset reorientating 0.1%. There were 3,313 (1.5%) revision THAs performed, of which 815 (0.4%) were for instability and 838 (0.4%) were for loosening. Compared to the LPW group, the adjusted subhazard ratio of revision for instability in the hooded group was 2.31 (p < 0.001) and 4.12 (p = 0.047) in the offset reorientating group. Likewise, the subhazard ratio of revision for loosening was 2.65 (p < 0.001) in the hooded group and 13.61 (p < 0.001) in the offset reorientating group. A time-varying subhazard ratio of revision for instability (hooded vs LPW) was found, being greatest within the first three months. Conclusion. This registry-based study confirms a significantly higher risk of revision after cemented THA for instability and for loosening when a hooded or offset reorientating acetabular component is used, compared to a LPW component. Further research is required to clarify if certain patients benefit from the use of hooded or offset reorientating components, but we recommend caution when using such components in routine clinical practice. Cite this article: Bone Joint J 2021;103-B(11):1669–1677

Aims. The use of technology to assess balance and alignment during total knee surgery can provide an overload of numerical data to the surgeon. Meanwhile, this quantification holds the potential to clarify and guide the surgeon through the surgical decision process when selecting the appropriate bone recut or soft tissue adjustment when balancing a total knee. Therefore, this paper evaluates the potential of deploying supervised machine learning (ML) models to select a surgical correction based on patient-specific intra-operative assessments. Methods. Based on a clinical series of 479 primary total knees and 1,305 associated surgical decisions, various ML models were developed. These models identified the indicated surgical decision based on available, intra-operative alignment, and tibiofemoral load data. Results. With an associated area under the receiver-operator curve ranging between 0.75 and 0.98, the optimized ML models resulted in good to excellent predictions. The best performing model used a random forest approach while considering both alignment and intra-articular load readings. Conclusion. The presented model has the potential to make experience available to surgeons adopting new technology, bringing expert opinion in their operating theatre, but also provides insight in the surgical decision process. More specifically, these promising outcomes indicated the relevance of considering the overall limb alignment in the coronal and sagittal plane to identify the appropriate surgical decision

Aims. The modified Radiological Union Scale for Tibia (mRUST) fractures score was developed in order to assess progress to union and define a numerical assessment of fracture healing of metadiaphyseal fractures. This score has been shown to be valuable in predicting radiological union; however, there is no information on the sensitivity, specificity, and accuracy of this index for various cut-off scores. The aim of this study is to evaluate sensitivity, specificity, accuracy, and cut-off points of the mRUST score for the diagnosis of metadiaphyseal fractures healing. Methods. A cohort of 146 distal femur fractures were retrospectively identified at our institution. After excluding AO/OTA type B fractures, nonunions, follow-up less than 12 weeks, and patients aged less than 16 years, 104 sets of radiographs were included for analysis. Anteroposterior and lateral femur radiographs at six weeks, 12 weeks, 24 weeks, and final follow-up were separately scored by three surgeons using the mRUST score. The sensitivity and specificity of mean mRUST score were calculated using clinical and further radiological findings as a gold standard for ultimate fracture healing. A receiver operating characteristic curve was also performed to determine the cut-off points at each time point. Results. The mean mRUST score of ten at 24 weeks revealed a 91.9% sensitivity, 100% specificity, and 92.6% accuracy of predicting ultimate fracture healing. A cut-off point of 13 points revealed 41.9% sensitivity, 100% specificity, and 46.9% accuracy at the same time point. Conclusion. The mRUST score of ten points at 24 weeks can be used as a viable screening method with the highest sensitivity, specificity, and accuracy for healing of metadiaphyseal femur fractures. However, the cut-off point of 13 increases the specificity to 100%, but decreases sensitivity. Furthermore, the mRUST score should not be used at six weeks, as results show an inability to accurately predict eventual fracture healing at this time point. Cite this article: Bone Jt Open 2021;2(10):796–805

Aims. This combined clinical and in vitro study aimed to determine the incidence of liner malseating in modular dual mobility (MDM) constructs in primary total hip arthroplasties (THAs) from a large volume arthroplasty centre, and determine whether malseating increases the potential for fretting and corrosion at the modular metal interface in malseated MDM constructs using a simulated corrosion chamber. Methods. For the clinical arm of the study, observers independently reviewed postoperative radiographs of 551 primary THAs using MDM constructs from a single manufacturer over a three-year period, to identify the incidence of MDM liner-shell malseating. Multivariable logistic regression analysis was performed to identify risk factors including age, sex, body mass index (BMI), cup design, cup size, and the MDM case volume of the surgeon. For the in vitro arm, six pristine MDM implants with cobalt-chrome liners were tested in a simulated corrosion chamber. Three were well-seated and three were malseated with 6° of canting. The liner-shell couples underwent cyclic loading of increasing magnitudes. Fretting current was measured throughout testing and the onset of fretting load was determined by analyzing the increase in average current. Results. The radiological review identified that 32 of 551 MDM liners (5.8%) were malseated. Malseating was noted in all of the three different cup designs. The incidence of malseating was significantly higher in low-volume MDM surgeons than high-volume MDM surgeons (p < 0.001). Pristine well-seated liners showed significantly lower fretting current values at all peak loads greater than 800 N (p < 0.044). Malseated liner-shell couples had lower fretting onset loads at 2,400 N. Conclusion. MDM malseating remains an issue that can occur in at least one in 20 patients at a high-volume arthroplasty centre. The onset of fretting and increased fretting current throughout loading cycles suggests susceptibility to corrosion when this occurs. These results support the hypothesis that malseated liners may be at risk for fretting corrosion. Clinicians should be aware of this phenomenon. Cite this article: Bone Joint J 2020;102-B(7 Supple B):20–26