Our aim was to evaluate the radiographic characteristics of patients
undergoing total hip arthroplasty (THA) for the potential of posterior
bony impingement using CT simulations. Virtual CT data from 112 patients who underwent THA were analysed.
There were 40 men and 72 women. Their mean age was 59.1 years (41
to 76). Associations between radiographic characteristics and posterior
bony impingement and the range of external rotation of the hip were
evaluated. In addition, we investigated the effects of pelvic tilt
and the neck/shaft angle and femoral offset on posterior bony impingement.Aims
Patients and Methods
Microindentation has the potential to measure the stiffness of an individual patient’s bone. Bone stiffness plays a crucial role in the press-fit stability of orthopaedic implants. Arming surgeons with accurate bone stiffness information may reduce surgical complications including periprosthetic fractures. The question addressed with this systematic review is whether microindentation can accurately measure cortical bone stiffness. A systematic review of all English language articles using a keyword search was undertaken using Medline, Embase, PubMed, Scopus and Cochrane databases. Studies that only used nanoindentation, cancellous bone or animal tissue were excluded.Objectives
Methods
To validate the precision of digitally reconstructed radiograph (DRR) radiostereometric analysis (RSA) and the model-based method (MBM) RSA with respect to benchmark marker-based (MM) RSA for evaluation of kinematics in the native hip joint. Seven human cadaveric hemipelves were CT scanned and bone models were segmented. Tantalum beads were placed in the pelvis and proximal femoral bone. RSA recordings of the hips were performed during flexion, adduction and internal rotation. Stereoradiographic recordings were all analyzed with DRR, MBM and MM. Migration results for the MBM and DRR with respect to MM were compared. Precision was assessed as systematic bias (mean difference) and random variation (Pitman’s test for equal variance).Objectives
Methods
The aim of this study was to examine the real time A total of 50 patients (83 hips) underwent 4D dynamic CT scanning
of the hip, producing real time osseous models of the pelvis and
femur being moved through flexion, adduction, and internal rotation.
The location and size of the cam deformity and its relationship
to the angle of flexion of the hip and pelvic tilt, and the position
of impingement were recorded.Aims
Patients and Methods
To compare the effect of femoral bone tunnel configuration on tendon-bone healing in an anterior cruciate ligament (ACL) reconstruction animal model. Anterior cruciate ligament reconstruction using the plantaris tendon as graft material was performed on both knees of 24 rabbits (48 knees) to mimic ACL reconstruction by two different suspensory fixation devices for graft fixation. For the adjustable fixation device model (Socket group; group S), a 5 mm deep socket was created in the lateral femoral condyle (LFC) of the right knee. For the fixed-loop model (Tunnel group; group T), a femoral tunnel penetrating the LFC was created in the left knee. Animals were sacrificed at four and eight weeks after surgery for histological evaluation and biomechanical testing.Objectives
Methods
Preserving growth following limb-salvage surgery of the upper
limb in children remains a challenge. Vascularized autografts may
provide rapid biological incorporation with the potential for growth
and longevity. In this study, we aimed to describe the outcomes
following proximal humeral reconstruction with a vascularized fibular
epiphyseal transfer in children with a primary sarcoma of bone.
We also aimed to quantify the hypertrophy of the graft and the annual
growth, and to determine the functional outcomes of the neoglenofibular
joint. We retrospectively analyzed 11 patients who underwent this procedure
for a primary bone tumour of the proximal humerus between 2004 and
2015. Six had Ewing’s sarcoma and five had osteosarcoma. Their mean
age at the time of surgery was five years (two to eight). The mean
follow-up was 5.2 years (1 to 12.2).Aims
Patients and Methods
The aim of this study was to investigate the changes in femoral
trochlear morphology following surgical correction of recurrent
patellar dislocation associated with trochlear dysplasia in children. A total of 23 patients with a mean age of 9.6 years (7 to 11)
were included All had bilateral recurrent patellar dislocation associated
with femoral trochlear dysplasia. The knee with traumatic dislocation
at the time of presentation or that had dislocated most frequently
was treated with medial patellar retinacular plasty (Group S). The
contralateral knee served as a control and was treated conservatively
(Group C). All patients were treated between October 2008 and August
2013. The mean follow-up was 48.7 months (43 to 56). Axial CT scans
were undertaken in all patients to assess the trochlear morphological
characteristics on a particular axial image which was established
at the point with the greatest epicondylar width based on measurements
preoperatively and at the final follow-up.Aims
Patients and Methods
Controversy about the use of an anatomical total shoulder arthroplasty
(aTSA) in young arthritic patients relates to which is the ideal
form of fixation for the glenoid component: cemented or cementless.
This study aimed to evaluate implant survival of aTSA when used
in patients aged < 60 years with primary glenohumeral osteoarthritis (OA),
and to compare the survival of cemented all-polyethylene and cementless
metal-backed glenoid components. A total of 69 consecutive aTSAs were performed in 67 patients
aged < 60 years with primary glenohumeral OA. Their mean age
at the time of surgery was 54 years (35 to 60). Of these aTSAs,
46 were undertaken using a cemented polyethylene component and 23
were undertaken using a cementless metal-backed component. The age, gender,
preoperative function, mobility, premorbid glenoid erosion, and
length of follow-up were comparable in the two groups. The patients
were reviewed clinically and radiographically at a mean of 10.3
years (5 to 12, Aims
Materials and Methods
The aim of this study was to investigate the clinical and radiographic
outcomes of microendoscopic laminotomy in patients with lumbar stenosis
and concurrent degenerative spondylolisthesis (DS), and to determine
the effect of this procedure on spinal stability. A total of 304 consecutive patients with single-level lumbar
DS with concomitant stenosis underwent microendoscopic laminotomy
without fusion between January 2004 and December 2010. Patients
were divided into two groups, those with and without advanced DS
based on the degree of spondylolisthesis and dynamic instability. A
total of 242 patients met the inclusion criteria. There were 101
men and 141 women. Their mean age was 68.1 years (46 to 85). Outcome
was assessed using the Japanese Orthopaedic Association and Roland
Morris Disability Questionnaire scores, a visual analogue score
for pain and the Short Form Health-36 score. The radiographic outcome
was assessed by measuring the slip and the disc height. The clinical
and radiographic parameters were evaluated at a mean follow-up of
4.6 years (3 to 7.5).Aims
Patients and Methods
After an injury, the biological reattachment of tendon to bone is a challenge because healing takes place between a soft (tendon) and a hard (bone) tissue. Even after healing, the transition zone in the enthesis is not completely regenerated, making it susceptible to re-injury. In this study, we aimed to regenerate Achilles tendon entheses (ATEs) in wounded rats using a combination of kartogenin (KGN) and platelet-rich plasma (PRP). Wounds created in rat ATEs were given three different treatments: kartogenin platelet-rich plasma (KGN-PRP); PRP; or saline (control), followed by histological and immunochemical analyses, and mechanical testing of the rat ATEs after three months of healing.Objectives
Methods
The morphometry of the distal femur was largely studied to improve
bone-implant fit in total knee arthroplasty (TKA), but little is
known about the asymmetry of the posterior condyles. This study
aimed to investigate the dimensions of the posterior condyles and
the influence of externally rotating the femoral component on potential prosthetic
overhang or under-coverage. We analysed the shape of 110 arthritic knees at the time of primary
TKA using pre-operative CT scans. The height and width of each condyle
were measured at the posterior femoral cut in neutral position,
and in 3º and 5º of external rotation, using both central and medial
referencing systems. We compared the morphological characteristics
with those of 14 TKA models.Aims
Patients and Methods
Pathological assessment of periprosthetic tissues is important, not only for diagnosis, but also for understanding the pathobiology of implant failure. The host response to wear particle deposition in periprosthetic tissues is characterised by cell and tissue injury, and a reparative and inflammatory response in which there is an innate and adaptive immune response to the material components of implant wear. Physical and chemical characteristics of implant wear influence the nature of the response in periprosthetic tissues and account for the development of particular complications that lead to implant failure, such as osteolysis which leads to aseptic loosening, and soft-tissue necrosis/inflammation, which can result in pseudotumour formation. The innate response involves phagocytosis of implant-derived wear particles by macrophages; this is determined by pattern recognition receptors and results in expression of cytokines, chemokines and growth factors promoting inflammation and osteoclastogenesis; phagocytosed particles can also be cytotoxic and cause cell and tissue necrosis. The adaptive immune response to wear debris is characterised by the presence of lymphoid cells and most likely occurs as a result of a cell-mediated hypersensitivity reaction to cell and tissue components altered by interaction with the material components of particulate wear, particularly metal ions released from cobalt-chrome wear particles. Cite this article: Professor N. A. Athanasou. The pathobiology and pathology of aseptic implant failure.
All-suture anchors are increasingly used in rotator cuff repair procedures. Potential benefits include decreased bone damage. However, there is limited published evidence for the relative strength of fixation for all-suture anchors compared with traditional anchors. A total of four commercially available all-suture anchors, the ‘Y-Knot’ (ConMed), Q-FIX (Smith & Nephew), ICONIX (Stryker) and JuggerKnot (Zimmer Biomet) and a traditional anchor control TWINFIX Ultra PK Suture Anchor (Smith & Nephew) were tested in cadaveric human humeral head rotator cuff repair models (n = 24). This construct underwent cyclic loading applied by a mechanical testing rig (Zwick/Roell). Ultimate load to failure, gap formation at 50, 100, 150 and 200 cycles, and failure mechanism were recorded. Significance was set at p < 0.05.Objectives
Materials and Methods
Adjuvant treatment after intralesional curettage for atypical
cartilaginous tumours (ACTs) of long bones is widely accepted for
extending surgical margins. However, evaluating the isolated effect
of adjuvant treatment is difficult, and it is unclear whether not
using such adjuvants provides poor oncological outcomes. Hence,
we analyzed whether intralesional curettage without cryosurgery
or chemical adjuvants provides poor oncological outcomes in patients
with an ACT. A total of 24 patients (nine men, 15 women) (mean age 45 years;
18 to 62) were treated for ACTs of long bones and followed up for
a median of 66 months (interquartile range 50 to 84). All patients
were treated with extensive manual curettage and limited burring.
Bone cement and grafts were used to fill bone defects in 16 and eight
patients, respectively. No chemical adjuvants or cryosurgery were
used.Aims
Patients and Methods
The purpose of this study was to develop an accurate, reliable and easily applicable method for determining the anatomical location of the joint line during revision knee arthroplasty. The transepicondylar width (TEW), the perpendicular distance between the medial and lateral epicondyles and the distal articular surfaces (DMAD, DLAD) and the distance between the medial and lateral epicondyles and the posterior articular surfaces (PMAD, DLAD) were measured in 40 knees from 20 formalin-fixed adult cadavers (11 male and nine female; mean age at death 56.9 years, Objectives
Methods
The aim of this study was to compare the effectiveness of a femoral
nerve block and a periarticular infiltration in the management of
early post-operative pain after total knee arthroplasty (TKA). A pragmatic, single centre, two arm parallel group, patient blinded,
randomised controlled trial was undertaken. All patients due for
TKA were eligible. Exclusion criteria included contraindications
to the medications involved in the study and patients with a neurological
abnormality of the lower limb. Patients received either a femoral
nerve block with 75 mg of 0.25% levobupivacaine hydrochloride around
the nerve, or periarticular infiltration with 150 mg of 0.25% levobupivacaine
hydrochloride, 10 mg morphine sulphate, 30 mg ketorolac trometamol
and 0.25 mg of adrenaline all diluted with 0.9% saline to make a
volume of 150 ml.Aims
Patients and Methods
Large bone defects remain a tremendous clinical challenge. There is growing evidence in support of treatment strategies that direct defect repair through an endochondral route, involving a cartilage intermediate. While culture-expanded stem/progenitor cells are being evaluated for this purpose, these cells would compete with endogenous repair cells for limited oxygen and nutrients within ischaemic defects. Alternatively, it may be possible to employ extracellular vesicles (EVs) secreted by culture-expanded cells for overcoming key bottlenecks to endochondral repair, such as defect vascularization, chondrogenesis, and osseous remodelling. While mesenchymal stromal/stem cells are a promising source of therapeutic EVs, other donor cells should also be considered. The efficacy of an EV-based therapeutic will likely depend on the design of companion scaffolds for controlled delivery to specific target cells. Ultimately, the knowledge gained from studies of EVs could one day inform the long-term development of synthetic, engineered nanovesicles. In the meantime, EVs harnessed from
