Aims

It is not known whether preservation of the capsule of the hip positively affects patient-reported outcome measures (PROMs) in total hip arthroplasty using the direct anterior approach (DAA-THA). A recent randomized controlled trial found no clinically significant difference at one year postoperatively. This study aimed to determine whether preservation of the anterolateral capsule and anatomical closure improve the outcome and revision rate, when compared with resection of the anterolateral capsule, at two years postoperatively.

Aims. High body mass index (BMI) is associated with increased rates of complications in primary total hip arthroplasty (THA), but less is known about its impact on cost. The effects of low BMI on outcomes and cost are less understood. This study evaluated the relationship between BMI, inpatient costs, complications, readmissions, and utilization of post-acute services. Methods. A retrospective database analysis of 40,913 primary THAs performed between January 2013 and December 2017 in 29 hospitals was conducted. Operating time, length of stay (LOS), complication rate, 30-day readmission rate, inpatient cost, and utilization of post-acute services were measured and compared in relation to patient BMI. Results. Mean operating time increased with BMI and for BMI > 50 kg/m. 2. was approximately twice that of BMI 10 kg/m. 2. to 15 kg/m. 2. Mean inpatient cost did not vary significantly with BMI. Mean total reimbursement was lowest for the lowest BMI cohort and increased with BMI. Mean LOS was greatest at the extremes of BMI (4.0 days for BMI 10 kg/m. 2. to 15 kg/m. 2. ; 3.75 days for BMI > 50 kg/m. 2. ) and twice that of normal BMI. Mean complication rates were greatest in the lowest BMI cohort (16% for BMI 10 kg/m. 2. to 15 kg/m. 2. ) and five times the mean rate of complications in the normal BMI cohorts. Furthermore, 30-day readmissions were greatest in the highest BMI cohort (10% for BMI > 50 kg/m. 2. ) and five times the rate for normal BMI patients. Conclusion. LOS, complications, and 30-day readmissions all increase at the extremes of BMI and appear to be greater than those of patients with normal BMI. The lowest BMI patients had the lowest payment for inpatient stay yet were at considerable risk for complications and readmission. Patients with extreme BMI should be counselled about their increased risk of complications for THA and nutritional status/obesity optimized preoperatively if possible. Cite this article: Bone Joint J 2020;102-B(7 Supple B):62–70

Aims. The purpose of this study was to investigate the prevalence of sarcopenia and to examine its impact on patients with degenerative lumbar spinal stenosis (DLSS). Patients and Methods. This case-control study included two groups: one group consisting of patients with DLSS and a second group of control subjects without low back or neck pain and related leg pain. Five control cases were randomly selected and matched by age and gender (n = 77 cases and n = 385 controls) for each DLSS case. Appendicular muscle mass, hand-grip strength, sit-to-stand test, timed up and go (TUG) test, and clinical outcomes, including the Oswestry Disability Index (ODI) scores and the EuroQol EQ-5D were compared between the two groups. Results. The prevalence of sarcopenia, as defined by hand-grip strength, was significantly higher in the DLSS group (24%) when compared with the age- and gender-matched control group (12%) (p = 0.004). In the DLSS group, the sarcopenia subgroup demonstrated inferior results for the TUG test and ODI scores when compared with the non-sarcopenia subgroup (p = 0.006 and p = 0.039, respectively) after adjusting for age and gender. Conclusion. This study demonstrated a higher prevalence of sarcopenia in patients with DLSS and highlighted its negative effect on clinical outcomes. Cite this article: Bone Joint J 2016;98-B:1093–8

We present the results of 62 consecutive acetabular revisions using impaction bone grafting and a cemented polyethylene acetabular component in 58 patients (13 men and 45 women) after a mean follow-up of 27 years (25 to 30). All patients were prospectively followed. The mean age at revision was 59.2 years (23 to 82). . We performed Kaplan–Meier (KM) analysis and also a Competing Risk (CR) analysis because with long-term follow-up, the presence of a competing event (i.e. death) prevents the occurrence of the endpoint of re-revision. . A total of 48 patients (52 hips) had died or had been re-revised at final review in March 2011. None of the deaths were related to the surgery. The mean Harris hip score of the ten surviving hips in ten patients was 76 points (45 to 99). The KM survivorship at 25 years for the endpoint ‘re-revision for any reason’ was 58.0% (95% confidence interval (CI) 38 to 73) and for ‘re-revision for aseptic loosening’ 72.1% (95% CI 51 to 85). With the CR analysis we calculated the KM analysis overestimates the failure rate with respectively 74% and 93% for these endpoints. The current study shows that acetabular impaction bone grafting revisions provide good clinical results at over 25 years. Cite this article: Bone Joint J 2015;97-B:1338–44

Aims. Positive ulnar variance is an established risk factor for idiopathic ulnar impaction syndrome (UIS). However, not all patients with positive ulnar variance develop symptomatic UIS and other factors, including the morphology of the lunate, may be involved. The aim of this study was to clarify the relationship between lunate morphology and idiopathic UIS. Patients and Methods. A cohort of 95 patients with idiopathic UIS (UIS group) was compared with 95 asymptomatic controls with positive ulnar variance. The shape of the lunate was measured using the capitate-triquetrum distance (CTD), ulnar coverage ratio (UCR), radiolunate distance and radiolunate angle. The association of radiographic parameters and lunate types with the development of UIS was investigated in univariable and multivariable analyses. Receiver operating characteristic curves were used to estimate a cutoff for any statistically significant variables. Results. The proportion of type II lunates, which have a medial hamate facet, were significantly higher in the UIS group than in the control group in the univariable analysis (p = 0.001). CTD (odds ratio (OR) 1.52; 95% confidence interval (CI) 1.11 to 2.06; p = 0.008) and UCR (OR 44.78; 95% CI 5.35 to 374.90; p = 0.002) showed a positive association with UIS in the multivariable analysis. Estimated cutoff values were 2.5 mm for the CTD (area under the curve (AUC) = 0.65) and 0.4 for the UCR (AUC = 0.64). Conclusion. The proportion of type II lunates was greater in the UIS group than in the control group. A large UCR, which represents the broad base of the lunate, was positively associated with the development of idiopathic UIS. Cite this article: Bone Joint J 2017;99-B:1508–14

The role of bone-graft extenders in impaction revision surgery is becoming increasingly important. Tricalcium phosphate and hydroxyapatite have been shown to be both biocompatible and osteoconductive, yet many surgeons remain reluctant to use them. The difficulty in handling bone-graft extenders can be partly alleviated by using porous particles and adding clotted blood. In an in vitro model we measured the cohesive properties of various impaction graft mixes. Several factors were evaluated including the use of pure bone graft compared with mixes with extender, washing the bone and the addition of clotted blood. Our findings showed that pure allograft bone particles had significantly higher cohesion than when mixed with extender (p < 0.001). Washing had no effect on cohesion. The addition of clotted blood significantly increased the cohesion of both pure bone (p < 0.019) and mixes with pure bone and with porous graft extender (p < 0.044)

In order to investigate the osteoinductive properties of allograft used in impaction grafting and the effect of strain during impaction on these properties, we designed an in vitro experiment to measure strain-related release of bone morphogenetic protein-7 (BMP-7) from fresh-frozen femoral head allograft. A total of 40 10 mm cubes of cancellous bone were cut from ten samples of fresh-frozen femoral head. The marrow was removed from the cubes and the baseline concentrations of BMP-7 were measured. Specimens from each femoral head were allocated to four groups and subjected to different compressive strains with a material testing machine, after which BMP-7 activity was reassessed. It was present in all groups. There was a linear increase of 102.1 pg/g (95% confidence interval 68.6 to 135.6) BMP-7 for each 10% increase in strain. At 80% strain the mean concentration of BMP-7 released (830.3 pg/g bone) was approximately four times that released at 20% strain. Activity of BMP-7 in fresh-frozen allograft has not previously been demonstrated. This study shows that the freezing and storage of femoral heads allows some maintenance of biological activity, and that impaction grafting provides a source of osteoinductive bone for remodelling. We have shown that BMP-7 is released from fresh-frozen femoral head cancellous bone in proportion to the strain applied to the bone. This suggests that the impaction process itself may contribute to the biological process of remodelling and bony incorporation

Impacted morsellised allografts have been used successfully to address the problem of poor bone stock in revision surgery. However, there are concerns about the transmission of pathogens, the high cost and the shortage of supply of donor bone. Bone-graft extenders, such as tricalcium phosphate (TCP) and hydroxyapatite (HA), have been developed to minimise the use of donor bone. In a human cadaver model we have evaluated the surgical and mechanical feasibility of a TCP/HA bone-graft extender during impaction grafting revision surgery. A TCP/HA allograft mix increased the risk of producing a fissure in the femur during the impaction procedure, but provided a higher initial mechanical stability when compared with bone graft alone. The implications of the use of this type of graft extender in impaction grafting revision surgery are discussed

We identified 1305 femoral impaction bone grafting revisions using the Exeter stem performed between 1989 and 2002 in 30 hospitals throughout Sweden. There were 1188 patients with a mean age of 71 years (29 to 94) followed up for between five and 18 years. The participating departments reported 70 further revisions in total, of which 57 could also be identified on the Swedish National Arthroplasty Registry. Kaplan-Meier survivorship for all causes of failure was 94.0% (95% confidence interval (CI) 92 to 96) for women and 94.7% (95% CI, 92 to 96) for men at 15 years. Survivorship at 15 years for aseptic loosening was 99.1% (95% CI 98.4 to 99.5), for infection 98.6% (95% CI 97.6 to 99.2), for subsidence 99.0% (95% CI 98.2 to 99.4) and for fracture 98.7% (95% CI 97.9 to 99.2). Statistically significant predictors of failure were the year in which revision was conducted (p < 0.001). The number of previous revisions was slightly above the level of signifance (p = 0.056). Age, gender, the length of the stem and previous septic loosening were not predictors of failure (p = 0.213, p = 0.399, p = 0.337, p = 0.687, respectively). The difference in survivorship between high- and low-volume departments was only 3% at ten years. We conclude that impaction bone grafting with the Exeter stem has an excellent long-term survivorship following revision arthroplasty. The technique of impaction grafting appears to be reliable, can be learned rapidly and produces a predictably low incidence of aseptic loosening

Aims

A limited number of investigations with conflicting results have described perivascular lymphocytic infiltration (PVLI) in the setting of total knee arthroplasty (TKA). The purpose of this study was to determine if PVLI found in TKAs at the time of aseptic revision surgery was associated with worse clinical outcomes and survivorship.

Objectives. Pedicle-lengthening osteotomy is a novel surgery for lumbar spinal stenosis (LSS), which achieves substantial enlargement of the spinal canal by expansion of the bilateral pedicle osteotomy sites. Few studies have evaluated the impact of this new surgery on spinal canal volume (SCV) and neural foramen dimension (NFD) in three different types of LSS patients. Methods. CT scans were performed on 36 LSS patients (12 central canal stenosis (CCS), 12 lateral recess stenosis (LRS), and 12 foraminal stenosis (FS)) at L4-L5, and on 12 normal (control) subjects. Mimics 14.01 workstation was used to reconstruct 3D models of the L4-L5 vertebrae and discs. SCV and NFD were measured after 1 mm, 2 mm, 3 mm, 4 mm, or 5 mm pedicle-lengthening osteotomies at L4 and/or L5. One-way analysis of variance was used to examine between-group differences. Results. In the intact state, SVC and NFD were significantly larger in the control group compared with the LSS groups (P<0.05). After lengthening at L4, the percentage increase in SCV (per millimetre) was LRS>CCS>FS>Control. After lengthening at L5 and L4-L5, the percentage increase in SCV (per millimetre) was LRS>FS>CCS>Control. After lengthening at L4 and L4-L5, the percentage increase in NFD (per millimetre) was FS>CCS>LRS>Control. After lengthening at L5, the percentage increase in NFD (per millimetre) was CCS>LRS>control>FS. Conclusions. LRS patients are the most suitable candidates for treatment with pedicle-lengthening osteotomy. Lengthening L4 pedicles produced larger percentage increases in NFD than lengthening L5 pedicles (p < 0.05). Lengthening L4 pedicles may be the most effective option for relieving foraminal compression in LSS patients. Cite this article: P. Li, L. Qian, W. D. Wu, C. F. Wu, J. Ouyang. Impact of pedicle-lengthening osteotomy on spinal canal volume and neural foramen size in three types of lumbar spinal stenosis. Bone Joint Res 2016;5:239–246. DOI: 10.1302/2046-3758.56.2000469

We studied various aspects of graft impaction and penetration of cement in an experimental model. Cancellous bone was removed proximally and local diaphyseal lytic defects were simulated in six human cadaver femora. After impaction grafting the specimens were sectioned and prepared for histomorphometric analysis. The porosity of the graft was lowest in Gruen zone 4 (52%) and highest in Gruen zone 1 (76%). At the levels of Gruen zones 6 and 2 the entire cross-section was almost filled with cement. Cement sometimes reached the endosteal surface in other Gruen zones. The mean peak impaction forces exerted with the impactors were negatively correlated with the porosity of the graft

Aims

The aim of this study was to investigate the distribution of phenotypes in Asian patients with end-stage osteoarthritis (OA) and assess whether the phenotype affected the clinical outcome and survival of mechanically aligned total knee arthroplasty (TKA). We also compared the survival of the group in which the phenotype unintentionally remained unchanged with those in which it was corrected to neutral.

Aims

There are reports of a marked increase in perioperative mortality in patients admitted to hospital with a fractured hip during the COVID-19 pandemic in the UK, USA, Spain, and Italy. Our study aims to describe the risk of mortality among patients with a fractured neck of femur in England during the early stages of the COVID-19 pandemic.

The application and interpretation of the impact factor of a journal is fraught with problems, some of which are explored in this editorial

We report the initial results of an ongoing randomised, prospective study on migration of the Exeter and Elite Plus femoral stems after impaction allografting, as measured by radiostereometry. Clinically, the impaction technique gave good results for both stems. The mean subsidence in the first year was 1.30 mm and 0.20 mm for the Exeter and the Elite Plus stems, respectively. In the second year, the Exeter stem continued to subside further by a mean of 0.42 mm, while the Elite Plus stem did not do so. Subsidence of the Exeter stem correlated with deficiency of bone stock as graded on the Gustilo and Pasternak scale. This correlation was not found for the Elite Plus stem. None of the other parameters which were studied predisposed to subsidence. There was no significant association between the amount of subsidence and the radiological appearance of the graft for either stem. Our findings do not support the theory that radial compression, due to subsidence of the Exeter stem, is the essential stimulus for remodelling in impaction allografting

This review summarises the technique of impaction grafting with mesh augmentation for the treatment of uncontained acetabular defects in revision hip arthroplasty. The ideal acetabular revision should restore bone stock, use a small socket in the near-anatomic position, and provide durable fixation. Impaction bone grafting, which has been in use for over 40 years, offers the ability to achieve these goals in uncontained defects. The precepts of modern, revision impaction grafting are that the segmental or cavitary defects must be supported with a mesh; the contained cavity is filled with vigorously impacted morselised fresh-frozen allograft; and finally, acrylic cement is used to stabilise the graft and provide rigid, long-lasting fixation of the revised acetabular component. Favourable results have been published with this technique. While having its limitations, it is a viable option to address large acetabular defects in revision arthroplasty. Cite this article: Bone Joint J 2017;99-B(1 Supple A):25–30

We reviewed the results of 71 revisions of the acetabular component in total hip replacement, using impaction of bone allograft. The mean follow-up was 7.2 years (1.6 to 9.7). All patients were assessed according to the American Academy of Orthopedic Surgeons (AAOS) classification of bone loss, the amount of bone graft required, thickness of the graft layer, signs of graft incorporation and use of augmentation. A total of 20 acetabular components required re-revision for aseptic loosening, giving an overall survival of 72% (95% CI, 54.4 to 80.5). Of these failures, 14 (70%) had an AAOS type III or IV bone defect. In the failed group, poor radiological and histological graft incorporation was seen. These results suggest that impaction allografting in acetabular revision with severe bone defects may have poorer results than have previously been reported