Bioresorbable orthopaedic devices with calcium phosphate (CaP) fillers are commercially available on the assumption that increased calcium (Ca) locally drives new bone formation, but the clinical benefits are unknown. Electron beam (EB) irradiation of polymer devices has been shown to enhance the release of Ca. The aims of this study were to: 1) establish the biological safety of EB surface-modified bioresorbable devices; 2) test the release kinetics of CaP from a polymer device; and 3) establish any subsequent beneficial effects on bone repair ActivaScrew Interference (Bioretec Ltd, Tampere, Finland) and poly(L-lactide-co-glycolide) (PLGA) orthopaedic screws containing 10 wt% β-tricalcium phosphate (β-TCP) underwent EB treatment. Objectives
Methods
The injured anterior cruciate ligament (ACL) is thought to exhibit an impaired healing response, and attempts at surgical repair have not been successful. Connective tissue growth factor (CTGF) is reported to be associated with wound healing, probably through transforming growth factor beta 1 (TGF-β1). A rabbit ACL injury model was used to study the effect of CTGF on ligament recovery. Quantitative real-time PCR (qRT-PCR) was performed for detection of changes in RNA levels of TGF-β1, type 1 collagen (COL1), type 2 collagen (COL2), SRY-related high mobility group-box gene9 (SOX9), tissue inhibitor of metalloproteinase-1 (TIMP-1) and matrix metallopeptidase 13 (MMP-13). Expression of related proteins was detected by Western blotting.Objectives
Methods
Tranexamic acid (TXA) is an anti-fibrinolytic medication commonly used to reduce perioperative bleeding. Increasingly, topical administration as an intra-articular injection or perioperative wash is being administered during surgery. Adult soft tissues have a poor regenerative capacity and therefore damage to these tissues can be harmful to the patient. This study investigated the effects of TXA on human periarticular tissues and primary cell cultures using clinically relevant concentrations. Tendon, synovium, and cartilage obtained from routine orthopaedic surgeries were used for Objectives
Methods
The objectives of this study were to compare postoperative pain, analgesia requirements, inpatient functional rehabilitation, time to hospital discharge, and complications in patients undergoing conventional jig-based unicompartmental knee arthroplasty (UKA) This prospective cohort study included 146 patients with symptomatic medial compartment knee osteoarthritis undergoing primary UKA performed by a single surgeon. This included 73 consecutive patients undergoing conventional jig-based mobile bearing UKA, followed by 73 consecutive patients receiving robotic-arm assisted fixed bearing UKA. All surgical procedures were performed using the standard medial parapatellar approach for UKA, and all patients underwent the same postoperative rehabilitation programme. Postoperative pain scores on the numerical rating scale and opiate analgesia consumption were recorded until discharge. Time to attainment of predefined functional rehabilitation outcomes, hospital discharge, and postoperative complications were recorded by independent observers.Aims
Patients and Methods
The aim of this study was to investigate the incidence, risk factors, and outcome of venous thromboembolism (VTE) following anterior cruciate ligament (ACL) reconstruction in a nationwide cohort. All ACL reconstructions, primary and revision, that were recorded in the Swedish Knee Ligament Register (SKLR) between 2006 and 2013 were linked with data from the Swedish National Board of Health and Welfare. The incidence of VTE was determined by entries between the day of surgery until 90 days postoperatively based on diagnosis codes and the prescription of anticoagulants. Risk factors, outcome, and the use of thromboprophylaxis were analyzed. Descriptive statistics with multivariate analysis were used to describe the findings.Aims
Patients and Methods
An evidence-based radiographic Decision Aid for meniscal-bearing
unicompartmental knee arthroplasty (UKA) has been developed and
this study investigates its performance at an independent centre. Pre-operative radiographs, including stress views, from a consecutive
cohort of 550 knees undergoing arthroplasty (UKA or total knee arthroplasty;
TKA) by a single-surgeon were assessed. Suitability for UKA was
determined using the Decision Aid, with the assessor blinded to
treatment received, and compared with actual treatment received, which
was determined by an experienced UKA surgeon based on history, examination,
radiographic assessment including stress radiographs, and intra-operative
assessment in line with the recommended indications as described
in the literature.Aims
Patients and Methods
While medial unicompartmental knee arthroplasty (UKA) is indicated
for patients with full-thickness cartilage loss, it is occasionally
used to treat those with partial-thickness loss. The aim of this
study was to investigate the five-year outcomes in a consecutive
series of UKAs used in patients with partial thickness cartilage
loss in the medial compartment of the knee. Between 2002 and 2014, 94 consecutive UKAs were undertaken in
90 patients with partial thickness cartilage loss and followed up
independently for a mean of six years (1 to 13). These patients
had partial thickness cartilage loss either on both femur and tibia
(13 knees), or on either the femur or the tibia, with full thickness
loss on the other surface of the joint (18 and 63 knees respectively).
Using propensity score analysis, these patients were matched 1:2 based
on age, gender and pre-operative Oxford Knee Score (OKS) with knees
with full thickness loss on both the femur and tibia. The functional
outcomes, implant survival and incidence of re-operations were assessed
at one, two and five years post-operatively. A subgroup of 36 knees
in 36 patients with partial thickness cartilage loss, who had pre-operative
MRI scans, was assessed to identify whether there were any factors
identified on MRI that predicted the outcome.Aims
Patients and Methods
Our aim was to perform a meta-analysis of the outcomes of revision
anterior cruciate ligament (ACL) reconstruction, comparing the use
of different types of graft. A search was performed of Medline and Pubmed using the terms
“Anterior Cruciate Ligament” and “ACL” combined with “revision”,
“re-operation” and “failure”. Only studies that reported the outcome
at a minimum follow-up of two years were included. Two authors reviewed
the papers, and outcomes were subdivided into autograft and allograft. Autograft
was subdivided into hamstring (HS) and bone-patellar tendon-bone
(BPTB). Subjective and objective outcome measures were analysed
and odds ratios with confidence intervals were calculated.Aims
Materials and Methods
Dislocation of the acromioclavicular joint is
a relatively common injury and a number of surgical interventions
have been described for its treatment. Recently, a synthetic ligament
device has become available and been successfully used, however,
like other non-native solutions, a compromise must be reached when
choosing non-anatomical locations for their placement. This cadaveric
study aimed to assess the effect of different clavicular anchorage points
for the Lockdown device on the reduction of acromioclavicular joint
dislocations, and suggest an optimal location. We also assessed
whether further stability is provided using a coracoacromial ligament
transfer (a modified Neviaser technique). The acromioclavicular
joint was exposed on seven fresh-frozen cadaveric shoulders. The
joint was reconstructed using the Lockdown implant using four different
clavicular anchorage points and reduction was measured. The coracoacromial
ligament was then transferred to the lateral end of the clavicle,
and the joint re-assessed. If the Lockdown ligament was secured
at the level of the conoid tubercle, the acromioclavicular joint
could be reduced anatomically in all cases. If placed medial or
2 cm lateral, the joint was irreducible. If the Lockdown was placed
1 cm lateral to the conoid tubercle, the joint could be reduced
with difficulty in four cases. Correct placement of the Lockdown
device is crucial to allow anatomical joint reduction. Even when the
Lockdown was placed over the conoid tubercle, anterior clavicle
displacement remained but this could be controlled using a coracoacromial
ligament transfer. Cite this article:
Graft-tunnel mismatch of the bone-patellar tendon-bone
(BPTB) graft is a major concern during anatomical anterior cruciate
ligament (ACL) reconstruction if the femoral tunnel is positioned
using a far medial portal technique, as the femoral tunnel tends
to be shorter compared with that positioned using a transtibial
portal technique. This study describes an accurate method of calculating
the ideal length of bone plugs of a BPTB graft required to avoid
graft–tunnel mismatch during anatomical ACL reconstruction using
a far medial portal technique of femoral tunnel positioning. Based on data obtained intra-operatively from 60 anatomical ACL
reconstruction procedures, we calculated the length of bone plugs
required in the BPTB graft to avoid graft–tunnel mismatch. When
this was prevented in all the 60 cases, we found that the mean length
of femoral bone plug that remained in contact with the interference
screw within the femoral tunnel was 14 mm (12 to 22) and the mean
length of tibial bone plug that remained in contact with the interference
screw within the tibial tunnel was 23 mm (18 to 28). These results
were used to validate theoretical formulae developed to predict
the required length of bone plugs in BPTB graft during anatomical
ACL reconstruction using a far medial portal technique. Cite this article:
Patient-specific (PS) implantation surgical technology has been introduced in recent years and a gradual increase in the associated number of surgical cases has been observed. PS technology uses a patient’s own geometry in designing a medical device to provide minimal bone resection with improvement in the prosthetic bone coverage. However, whether PS unicompartmental knee arthroplasty (UKA) provides a better biomechanical effect than standard off-the-shelf prostheses for UKA has not yet been determined, and still remains controversial in both biomechanical and clinical fields. Therefore, the aim of this study was to compare the biomechanical effect between PS and standard off-the-shelf prostheses for UKA. The contact stresses on the polyethylene (PE) insert, articular cartilage and lateral meniscus were evaluated in PS and standard off-the-shelf prostheses for UKA using a validated finite element model. Gait cycle loading was applied to evaluate the biomechanical effect in the PS and standard UKAs.Objectives
Methods
Posterior condylar offset (PCO) and posterior tibial slope (PTS) are critical factors in total knee arthroplasty (TKA). A computational simulation was performed to evaluate the biomechanical effect of PCO and PTS on cruciate retaining TKA. We generated a subject-specific computational model followed by the development of ± 1 mm, ± 2 mm and ± 3 mm PCO models in the posterior direction, and -3°, 0°, 3° and 6° PTS models with each of the PCO models. Using a validated finite element (FE) model, we investigated the influence of the changes in PCO and PTS on the contact stress in the patellar button and the forces on the posterior cruciate ligament (PCL), patellar tendon and quadriceps muscles under the deep knee-bend loading conditions.Objectives
Methods
We used immediate post-operative The bending angles in the sagittal and axial planes were significantly
greater but the coronal-bending angle was significantly less in
the transtibial group than in the anteromedial portal and outside-in
groups (p <
0.001 each). The mean length of the femoral tunnel
in all three planes was significantly greater in the transtibial
group than the anteromedial portal and outside-in groups (p <
0.001 each), but all mean tunnel lengths in the three groups exceeded
30 mm. The only significant difference was the coronal graft- bending
angle in the anteromedial portal and outside-in groups (23.5° Compared with the transtibial technique, the anteromedial portal
and outside-in techniques may reduce the graft-bending stress at
the opening of the femoral tunnel. Despite the femoral tunnel length
being shorter in the anteromedial portal and outside-in techniques
than in the transtibial technique, a femoral tunnel length of more than
30 mm in the anteromedial portal and outside-in techniques may be
sufficient for the graft to heal. Cite this article:
The June 2015 Research Roundup360 looks at: Tranexamic acid: just give it – it’s not important how!; The anterolateral ligament re-examined; Warfarin a poor post-operative agent; Passive exoskeleton the orthosis of the future?; Musculoskeletal medicine: a dark art to UK medical students?; Alendronic acid and bone density post arthroplasty; Apples with oranges? Knee functional scores revisited
We report on the long-term results of 163 bicruciate-retaining
Hermes 2C total knee replacements in 130 patients at a mean follow-up
of 22.4 years (20.3 to 23.5). Even when the anterior cruciate ligament
had a partially degenerative appearance it was preserved as long
as the knee had a normal anterior drawer and Lachman’s test pre-operatively. The
description and surgical technique of this minimally constrained
prosthesis were published in 1983 and the ten-year clinical results
in 1999. A total of 12% of the knees (20 of 163) in this study were revised
because of wear of the polyethylene tibial insert. Excellent stability
was achieved and the incidence of aseptic component loosening was
4.3% (seven of 163). The survival rate using revision for any reason
as the endpoint was 82% (95% confidence interval 76.2 to 88.0). Although this series included a relatively small number of replacements,
it demonstrated that the anterior cruciate ligament, even when partially
degenerated at the time of TKR, remained functional and provided
adequate stability at a long-term follow-up. Cite this article:
