Loss of motion following spine segment fusion results in increased strain in the adjacent motion segments. However, to date, studies on the biomechanics of the cervical spine have not assessed the role of coupled motions in the lumbar spine. Accordingly, we investigated the biomechanics of the cervical spine following cervical fusion and lumbar fusion during simulated whiplash using a whole-human finite element (FE) model to simulate coupled motions of the spine. A previously validated FE model of the human body in the driver-occupant position was used to investigate cervical hyperextension injury. The cervical spine was subjected to simulated whiplash exposure in accordance with Euro NCAP (the European New Car Assessment Programme) testing using the whole human FE model. The coupled motions between the cervical spine and lumbar spine were assessed by evaluating the biomechanical effects of simulated cervical fusion and lumbar fusion.Objectives
Methods
We assessed the long-term (more than ten-year) outcomes of the
Kudo type-5 elbow prosthesis in patients with rheumatoid arthritis
(RA). We reviewed 41 elbows (Larsen Grade IV, n = 21; Grade V, n =
20) in 31 patients with RA who had undergone a Kudo type-5 total
elbow arthroplasty (TEA) between 1994 and 2003, and had been followed
up for more than ten years. The humeral component was cementless
and the all-polyethylene ulnar component cemented in every patient. Clinical
outcome was assessed using the Mayo elbow performance score. We
calculated the revision rate and evaluated potential risk factors
for revision. The duration of follow-up was a mean 141 months (120
to 203).Aims
Materials and Methods
The aim of this study was to report a retrospective, consecutive
series of patients with adolescent idiopathic scoliosis (AIS) who
were treated with posterior minimally invasive surgery (MIS) with
a mean follow-up of two years ( We prospectively collected the data of 70 consecutive patients
with AIS treated with MIS using three incisions and a muscle-splitting
approach by a single surgeon between June 2013 and February 2016
and these were retrospectively reviewed. There were eight male and
62 female patients with a mean age of 15 years (Aims
Patients and Methods
The role of high tibial osteotomy (HTO) is being questioned by
the use of unicompartmental knee arthroplasty (UKA) in the treatment
of medial compartment femorotibial osteoarthritis. Our aim was to
compare the outcomes of revision HTO or UKA to a total knee arthroplasty
(TKA) using computer-assisted surgery in matched groups of patients. We conducted a retrospective study to compare the clinical and
radiological outcome of patients who underwent revision of a HTO
to a TKA (group 1) with those who underwent revision of a medial
UKA to a TKA (group 2). All revision procedures were performed using
computer-assisted surgery. We extracted these groups of patients
from our database. They were matched by age, gender, body mass index,
follow-up and pre-operative functional score. The outcomes included
the Knee Society Scores (KSS), radiological outcomes and the rate
of further revision.Aims
Patients and Methods
Favourable results for collarless polished tapered stems have been reported, and cement creep due to taper slip may be a contributing factor. However, the ideal cement thickness around polished stems remains unknown. We investigated the influence of cement thickness on stem subsidence and cement creep. We cemented six collarless polished tapered (CPT) stems (two stems each of small, medium and large sizes) into composite femurs that had been reamed with a large CPT rasp to achieve various thicknesses of the cement mantle. Two or three tantalum balls were implanted in the proximal cement in each femur. A cyclic loading test was then performed for each stem. The migration of the balls was measured three-dimensionally, using a micro-computed tomography (CT) scanner, before and after loading. A digital displacement gauge was positioned at the stem shoulder, and stem subsidence was measured continuously by the gauge. Final stem subsidence was measured at the balls at the end of each stem.Objectives
Methods
One method of femoral head preservation following avascular necrosis
(AVN) is core decompression and insertion of a tantalum rod. However,
there may be a high failure rate associated with this procedure.
The purpose of this study was to document the clinical and radiological
outcomes following total hip arthroplasty (THA) subsequent to failed
tantalum rod insertion. A total of 37 failed tantalum rods requiring total hip arthroplasty
were identified from a prospective database. There were 21 hips
in 21 patients (12 men and nine women, mean age 37 years, 18 to
53) meeting minimum two year clinical and radiographic follow-up
whose THAs were carried out between November 2002 and April 2013
(mean time between tantalum rod implantation and conversion to a
THA was 26 months, 6 to 72). These were matched by age and gender
to individuals (12 men, nine women, mean age 40 years, 18 to 58)
receiving THA for AVN without prior tantalum rod insertion.Aims
Patients and Methods
The last decade has seen a considerable increase
in the use of in total ankle arthroplasty (TAA) to treat patients
with end-stage arthritis of the ankle. However, the longevity of
the implants is still far from that of total knee and hip arthroplasties. The aim of this review is to outline a diagnostic and treatment
algorithm for the painful TAA to be used when considering revision
surgery. Cite this article:
The purpose of this study was to clarify the appearance of the reparative tissue on the articular surface and to analyse the properties of the reparative tissue after hemicallotasis osteotomy (HCO) using MRI T1ρ and T2 mapping. Coronal T1ρ and T2 mapping and three-dimensional gradient-echo images were obtained from 20 subjects with medial knee osteoarthritis. We set the regions of interest (ROIs) on the full-thickness cartilage of the medial femoral condyle (MFC) and medial tibial plateau (MTP) of the knee and measured the cartilage thickness (mm) and T1ρ and T2 relaxation times (ms). Statistical analysis of time-dependent changes in the cartilage thickness and the T1ρ and T2 relaxation times was performed using one-way analysis of variance, and Scheffe’s test was employed for Objectives
Methods
There is a paucity of information on the pre-operative coronal
imbalance in patients with degenerative lumbar scoliosis (DLS) and
its influence on surgical outcomes. A total of 284 DLS patients were recruited into this study, among
whom 69 patients were treated surgically and the remaining 215 patients
conservatively Patients were classified based on the coronal balance
distance (CBD): Type A, CBD <
3 cm; Type B, CBD >
3 cm and C7
Plumb Line (C7PL) shifted to the concave side of the curve; Type
C, CBD >
3 cm and C7PL shifted to the convex side.Aims
Patients and Methods
To address the natural history of severe post-tuberculous (TB)
kyphosis, with focus upon the long-term neurological outcome, occurrence
of restrictive lung disease, and the effect on life expectancy. This is a retrospective clinical review of prospectively collected
imaging data based at a single institute. A total of 24 patients
of Southern Chinese origin who presented with spinal TB with a mean
of 113° of kyphosis (65° to 159°) who fulfilled inclusion criteria
were reviewed. Plain radiographs were used to assess the degree
of spinal deformity. Myelography, CT and MRI were used when available
to assess the integrity of the spinal cord and canal. Patient demographics,
age of onset of spinal TB and interventions, types of surgical procedure,
intra- and post-operative complications, and neurological status
were assessed. Aims
Patients and Methods
Since redesign of the Oxford phase III mobile-bearing unicompartmental
knee arthroplasty (UKA) femoral component to a twin-peg design,
there has not been a direct comparison to total knee arthroplasty
(TKA). Thus, we explored differences between the two cohorts. A total of 168 patients (201 knees) underwent medial UKA with
the Oxford Partial Knee Twin-Peg. These patients were compared with
a randomly selected group of 177 patients (189 knees) with primary
Vanguard TKA. Patient demographics, Knee Society (KS) scores and
range of movement (ROM) were compared between the two cohorts. Additionally,
revision, re-operation and manipulation under anaesthesia rates
were analysed.Aims
Patients and Methods
Episodic, or bundled payments, is a concept now
familiar to most in the healthcare arena, but the models are often
misunderstood. Under a traditional fee-for-service model, each provider
bills separately for their services which creates financial incentives
to maximise volumes. Under a bundled payment, a single entity, often
referred to as a convener (maybe the hospital, the physician group,
or a third party) assumes the risk through a payer contract for
all services provided within a defined episode of care, and receives
a single (bundled) payment for all services provided for that episode.
The time frame around the intervention is variable, but defined
in advance, as are included and excluded costs. Timing of the actual payment
in a bundle may either be before the episode occurs (prospective
payment model), or after the end of the episode through a reconciliation
(retrospective payment model). In either case, the defined costs
over the defined time frame are borne by the convener. Cite this article:
We wished to compare the clinical outcome, as assessed by questionnaires
and the rate of complications, in total knee arthroplasty (TKA)
undertaken with patient-matched positioning guides (PMPGs) or conventional
instruments. A total of 180 patients (74 men, 106 women; mean age 67 years)
were included in a multicentre, adequately powered, double-blind,
randomised controlled trial. The mean follow-up was 44 months (24
to 57).Aims
Patients and Methods
Preservation of posterior condylar offset (PCO) has been shown to correlate with improved functional results after primary total knee arthroplasty (TKA). Whether this is also the case for revision TKA, remains unknown. The aim of this study was to assess the independent effect of PCO on early functional outcome after revision TKA. A total of 107 consecutive aseptic revision TKAs were performed by a single surgeon during an eight-year period. The mean age was 69.4 years (39 to 85) and there were 59 female patients and 48 male patients. The Oxford Knee Score (OKS) and Short-form (SF)-12 score were assessed pre-operatively and one year post-operatively. Patient satisfaction was also assessed at one year. Joint line and PCO were assessed radiographically at one year.Objectives
Methods
Due to the complex anatomy of the pelvis, limb-sparing resections
of pelvic tumours achieving adequate surgical margins, can often
be difficult. The advent of computer navigation has improved the
precision of resection of these lesions, though there is little
evidence comparing resection with or without the assistance of navigation. Our aim was to evaluate the efficacy of navigation-assisted surgery
for the resection of pelvic bone tumours involving the posterior
ilium and sacrum. Using our prospectively updated institutional database, we conducted
a retrospective case control study of 21 patients who underwent
resection of the posterior ilium and sacrum, for the treatment of
a primary sarcoma of bone, between 1987 and 2015. The resection
was performed with the assistance of navigation in nine patients
and without navigation in 12. We assessed the accuracy of navigation-assisted
surgery, as defined by the surgical margin and how this affects
the rate of local recurrence, the disease-free survival and the
effects on peri-and post-operative morbidity. Aims
Patients and Methods
