Aims

Intraoperative pressure sensors allow surgeons to quantify soft-tissue balance during total knee arthroplasty (TKA). The aim of this study was to determine whether using sensors to achieve soft-tissue balance was more effective than manual balancing in improving outcomes in TKA.

Artificial intelligence (AI) is, in essence, the concept of ‘computer thinking’, encompassing methods that train computers to perform and learn from executing certain tasks, called machine learning, and methods to build intricate computer models that both learn and adapt, called complex neural networks. Computer vision is a function of AI by which machine learning and complex neural networks can be applied to enable computers to capture, analyze, and interpret information from clinical images and visual inputs. This annotation summarizes key considerations and future perspectives concerning computer vision, questioning the need for this technology (the ‘why’), the current applications (the ‘what’), and the approach to unlocking its full potential (the ‘how’).

Cite this article: Bone Joint J 2022;104-B(8):911–914.

The complications of impaction bone grafting in revision hip replacement includes fracture of the femur and subsidence of the prosthesis. In this in vitro study we aimed to investigate whether the use of vibration, combined with a perforated tamp during the compaction of morsellised allograft would reduce peak loads and hoop strains in the femur as a surrogate marker of the risk of fracture and whether it would also improve graft compaction and prosthetic stability. We found that the peak loads and hoop strains transmitted to the femoral cortex during graft compaction and subsidence of the stem in subsequent mechanical testing were reduced. This innovative technique has the potential to reduce the risk of intra-operative fracture and to improve graft compaction and therefore prosthetic stability

The August 2015 Oncology Roundup. 360 . looks at: Glasgow prognostic score in soft-tissue sarcoma; Denosumab in giant cell tumour; Timing, complications and radiotherapy; Pigmented villonodular synovitis and arthroscopy; PATHFx: estimating survival in pathological cancer; Prosthetic lengthening of short stumps; Chondrosarcoma and pathological fracture

Aims. The aim of this paper was to present the clinical features of patients with musculoskeletal sources of methicillin-sensitive Staphylococcus aureus (MSSA) septicaemia. Patients and Methods. A total of 137 patients presented with MSSA septicaemia between 2012 and 2015. The primary source of infection was musculoskeletal in 48 patients (35%). Musculoskeletal infection was considered the primary source of septicaemia when endocarditis and other obvious sources were excluded. All patients with an arthroplasty at the time were evaluated for any prosthetic involvement. . Results. The most common site of infection was the spine, which occurred in 28 patients (58%), and was associated with abscess formation in 16. Back pain was the presenting symptom in these patients, with a positive predictive value of 100%. A total of 24 patients had a total of 42 arthroplasties of the hip or knee in situ. Prosthetic joint infection occurred in six of these patients (25%). In five patients, the infection originated outside the musculoskeletal system. Three patients (6%) with MSSA septicaemia from a musculoskeletal sources died. . Conclusion. Amongst the musculoskeletal sources of MSSA septicaemia, the spine was the most commonly involved. We recommend an MRI scan of the whole spine and pelvis in patients with MSSA septicaemia with back pain, when the primary source of infection has not been identified or clinical examination is unreliable. Cite this article: Bone Joint J 2017;99-B:1545–51

The treatment of substantial proximal femoral bone loss in young patients with developmental dysplasia of the hip (DDH) is challenging. We retrospectively analysed the outcome of 28 patients (30 hips) with DDH who underwent revision total hip replacement (THR) in the presence of a deficient proximal femur, which was reconstructed with an allograft prosthetic composite. The mean follow-up was 15 years (8.5 to 25.5). The mean number of previous THRs was three (1 to 8). The mean age at primary THR and at the index reconstruction was 41 years (18 to 61) and 58.1 years (32 to 72), respectively. The indication for revision included mechanical loosening in 24 hips, infection in three and peri-prosthetic fracture in three. Six patients required removal and replacement of the allograft prosthetic composite, five for mechanical loosening and one for infection. The survivorship at ten, 15 and 20 years was 93% (95% confidence interval (CI) 91 to 100), 75.5% (95% CI 60 to 95) and 75.5% (95% CI 60 to 95), respectively, with 25, eight, and four patients at risk, respectively. Additionally, two junctional nonunions between the allograft and host femur required bone grafting and plating. An allograft prosthetic composite affords a good long-term outcome in the management of proximal femoral bone loss in revision THR in patients with DDH, while preserving distal host bone

Excision of the proximal femur for tumour with prosthetic reconstruction using a bipolar femoral head places a considerable load on the unreplaced acetabulum. . We retrospectively reviewed the changes which occur around the affected hip joint by evaluating the post-operative radiographs of 65 consecutive patients who underwent proximal prosthetic arthroplasty of the femur, and in whom an acetabular component had not been used. There were 37 men and 28 women with a mean age of 57.3 years (17 to 93). Radiological assessment included the extent of degenerative change in the acetabulum, heterotopic ossification, and protrusio acetabuli. . The mean follow-up was 9.1 years (2 to 11.8). Degenerative changes in the acetabulum were seen in three patients (4.6%), Brooker grade 1 or 2 heterotopic ossification in 17 (26%) and protrusion of the prosthetic head in nine (13.8%). . A total of eight patients (12.3%) needed a revision. Five were revised to the same type of prosthesis and three (4.6%) were converted to a total hip arthroplasty. . We conclude that radiological evidence of degenerative change, heterotopic ossification and protrusion occur in a few patients who undergo prosthetic arthroplasty of the proximal femur for tumour. The limited extent of these changes and the lack of associated symptoms do not justify the routine arthroplasty of the acetabulum in these patients. . Cite this article: Bone Joint J 2015;97-B:1704–9

Many aspects of total knee arthroplasty have changed since its inception. Modern prosthetic design, better fixation techniques, improved polyethylene wear characteristics and rehabilitation, have all contributed to a large change in revision rates. Arthroplasty patients now expect longevity of their prostheses and demand functional improvement to match. This has led to a re-examination of the long-held belief that mechanical alignment is instrumental to a successful outcome and a focus on restoring healthy joint kinematics. A combination of kinematic restoration and uncemented, adaptable fixation may hold the key to future advances. Cite this article: Bone Joint J 2015;97-B(10 Suppl A):16–19

Periprosthetic joint infection (PJI) is a difficult complication requiring a comprehensive eradication protocol. Cure rates have essentially stalled in the last two decades, using methods of antimicrobial cement joint spacers and parenteral antimicrobial agents. Functional spacers with higher-dose antimicrobial-loaded cement and antimicrobial-loaded calcium sulphate beads have emphasized local antimicrobial delivery on the premise that high-dose local antimicrobial delivery will enhance eradication. However, with increasing antimicrobial pressures, microbiota have responded with adaptive mechanisms beyond traditional antimicrobial resistance genes. In this review we describe adaptive resistance mechanisms that are relevant to the treatment of PJI. Some mechanisms are well known, but others are new. The objective of this review is to inform clinicians of the known adaptive resistance mechanisms of microbes relevant to PJI. We also discuss the implications of these adaptive mechanisms in the future treatment of PJI.

Cite this article: Bone Joint J 2022;104-B(5):575–580.

Aims. To evaluate the effectiveness of an institutionally developed algorithm for evaluation and diagnosis of prosthetic joint injection and to determine the impact of this protocol on overall hospital re-admissions.p. Patients and Methods. We retrospectively evaluated 2685 total hip arthroplasty (THA) and total knee arthroplasty (TKA) patients prior to (1263) and following (1422) the introduction of an infection detection protocol. The protocol used conservative thresholds for C-reactive protein to direct the medical attendant to aspirate the joint. The protocol incorporated a clear set of laboratory and clinical criteria that allowed a patient to be discharged home if all were met. Patients were included if they presented to our emergency department within 120 days post-operatively with concerns for swelling, pain or infection and were excluded if they had an unambiguous infection or if their chief complaint was non-orthopaedic in nature. Results. Concern for infection was the single most common (32%) reason for presentation. A total of 296 patients made an emergency visit and were included following THA or TKA. In the pre-protocol cohort, 11 of 27 patients were formally re-admitted to the hospital with concern for infection but only five (45%) patients had actual infections and received additional treatment. In comparison, in the post-protocol cohort, 11 patients were admitted for suspected infection, nine (82%) of whom were truly infected (p = 0.04). Sensitivity increased from 83% to 100% and specificity increased from 71% to 96%. Implementation of this protocol did not miss any infections. Conclusion. A standardised protocol for evaluation of THA and TKA infections significantly reduced unnecessary hospital re-admissions. The protocol was both sensitive and specific and did not compromise quality of care. Cite this article: Bone Joint J 2017;99-B:1603–10

Aims

Adverse spinal motion or balance (spine mobility) and adverse pelvic mobility, in combination, are often referred to as adverse spinopelvic mobility (SPM). A stiff lumbar spine, large posterior standing pelvic tilt, and severe sagittal spinal deformity have been identified as risk factors for increased hip instability. Adverse SPM can create functional malposition of the acetabular components and hence is an instability risk. Adverse pelvic mobility is often, but not always, associated with abnormal spinal motion parameters. Dislocation rates for dual-mobility articulations (DMAs) have been reported to be between 0% and 1.1%. The aim of this study was to determine the early survivorship from the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) of patients with adverse SPM who received a DMA.

Aims. The aim of this consensus was to develop a definition of post-operative fibrosis of the knee. Patients and Methods. An international panel of experts took part in a formal consensus process composed of a discussion phase and three Delphi rounds. Results. Post-operative fibrosis of the knee was defined as a limited range of movement (ROM) in flexion and/or extension, that is not attributable to an osseous or prosthetic block to movement from malaligned, malpositioned or incorrectly sized components, metal hardware, ligament reconstruction, infection (septic arthritis), pain, chronic regional pain syndrome (CRPS) or other specific causes, but due to soft-tissue fibrosis that was not present pre-operatively. Limitation of movement was graded as mild, moderate or severe according to the range of flexion (90° to 100°, 70° to 89°, < 70°) or extension deficit (5° to 10°, 11° to 20°, > 20°). Recommended investigations to support the diagnosis and a strategy for its management were also agreed. Conclusion. The development of standardised, accepted criteria for the diagnosis, classification and grading of the severity of post-operative fibrosis of the knee will facilitate the identification of patients for inclusion in clinical trials, the development of clinical guidelines, and eventually help to inform the management of this difficult condition. Cite this article: Bone Joint J 2016;98-B:1479–88

We report the kinematic and early clinical results of a patient- and observer-blinded randomised controlled trial in which CT scans were used to compare potential impingement-free range of movement (ROM) and acetabular component cover between patients treated with either the navigated ‘femur-first’ total hip arthroplasty (THA) method (n = 66; male/female 29/37, mean age 62.5 years; 50 to 74) or conventional THA (n = 69; male/female 35/34, mean age 62.9 years; 50 to 75). The Hip Osteoarthritis Outcome Score, the Harris hip score, the Euro-Qol-5D and the Mancuso THA patient expectations score were assessed at six weeks, six months and one year after surgery. A total of 48 of the patients (84%) in the navigated ‘femur-first’ group and 43 (65%) in the conventional group reached all the desirable potential ROM boundaries without prosthetic impingement for activities of daily living (ADL) in flexion, extension, abduction, adduction and rotation (p = 0.016). Acetabular component cover and surface contact with the host bone were > 87% in both groups. There was a significant difference between the navigated and the conventional groups’ Harris hip scores six weeks after surgery (p = 0.010). There were no significant differences with respect to any clinical outcome at six months and one year of follow-up. The navigated ‘femur-first’ technique improves the potential ROM for ADL without prosthetic impingement, although there was no observed clinical difference between the two treatment groups. Cite this article: Bone Joint J 2015; 97-B:890–8

Aims

Total knee arthroplasty (TKA) is a common and safe orthopaedic procedure. Zimmer Biomet's NexGen is the second most popular brand of implant used in the UK. The primary cause of revision after the first year is aseptic loosening. We present our experience of using this implant, with significant concerns around its performance with regards early aseptic loosening of the tibial component.

Objectives. Computed tomography (CT) plays an important role in evaluating wear and periacetabular osteolysis (PAO) in total hip replacements. One concern with CT is the high radiation exposure since standard pelvic CT provides approximately 3.5 millisieverts (mSv) of radiation exposure, whereas a planar radiographic examination with three projections totals approximately 0.5 mSv. The objective of this study was to evaluate the lowest acceptable radiation dose for dual-energy CT (DECT) images when measuring wear and periacetabular osteolysis in uncemented metal components. Materials and Methods. A porcine pelvis with bilateral uncemented hip prostheses and with known linear wear and acetabular bone defects was examined in a third-generation multidetector DECT scanner. The examinations were performed with four different radiation levels both with and without iterative reconstruction techniques. From the high and low peak kilo voltage acquisitions, polychrmoatic images were created together with virtual monochromatic images of energies 100 kiloelectron volts (keV) and 150 keV. Results. We could assess wear and PAO while substantially lowering the effective radiation dose to 0.7 mSv for a total pelvic view with an accuracy of around 0.5 mm for linear wear and 2 mm to 3 mm for PAO. Conclusion. CT for detection of prosthetic wear and PAO could be used with clinically acceptable accuracy at a radiation exposure level equal to plain radiographic exposures. Cite this article: B. Sandgren, M. Skorpil, P. Nowik, H. Olivecrona, J. Crafoord, L. Weidenhielm, A. Persson. Assessment of wear and periacetabular osteolysis using dual energy computed tomography on a pig cadaver to identify the lowest acceptable radiation dose. Bone Joint Res 2016;5:307–313. DOI: 10.1302/2046-3758.57.2000566

Aims

Giant cell tumour of bone (GCTB) treatment changed since the introduction of denosumab from purely surgical towards a multidisciplinary approach, with recent concerns of higher recurrence rates after denosumab. We evaluated oncological, surgical, and functional outcomes for distal radius GCTB, with a critically appraised systematic literature review.

The purpose of this paper has been to stimulate interest in amputation surgery, prosthetics and orthotics, and to illustrate the excellent work done in only some of the centres within the British Isles and to enlist the assistance of all orthopaedic surgeons in improving the orthotic equipment of their patients. We also need the interest and the practical involvement of one orthopaedic surgeon in amputation work and prosthetics in almost every large hospital, particularly in the centres where it is to be expected that limb-fitting units will be installed and fully integrated within the hospital service. It is necessary to say "almost every large hospital", because in some the vascular surgeon will lead the amputation and prosthetic team. This is a worthwhile special interest for the orthopaedic surgeon. The need presents itself not only for the geriatric patient with limb ischaemia and for those who lose a limb from trauma, but also for the quite considerable number of children who are congenitally without a limb or part of a limb. Orthopaedic surgery embraces a wide field, and in the larger centres the best work will result from a voluntary restriction in the field of operation of individual surgeons, many being involved in trauma and fractures, all being involved in adult orthopaedic surgery, some with a special interest and considerable time in children's orthopaedic surgery, or hand surgery, or the surgery of rheumatoid arthritis patient; and to this list one would hope might be added amputation surgery and the prosthetic rehabilitation of these patients. I will be well satisfied if I have succeeded in stimulating a renewed interest in this oldest branch of orthopaedic surgery