The December 2012 Shoulder &
Elbow Roundup360 looks at: whether allograft is biomechanically superior in large Hill-Sachs defects; glenoid bone loss in shoulder dislocators; repairing irreparable cuff tears; acromioclavicular joint injuries; whether more radiographs equals more surgery; whether reverse TSR is cheaper than hemiarthroplasty; autologous chondrocyte implantation in the shoulder; and fracture of the clavicle.
This study reports the clinical and sonographic
outcome of arthroscopic rotator cuff repair in patients aged ≥ 70 years
and aimed to determine factors associated with re-tear. A total
of 69 consecutive repairs were performed in 68 patients with a mean
age of 77 years (70 to 86). Constant-Murley scores were collected
pre-operatively and at one year post-operatively. The integrity
of the repair was assessed using ultrasound. Re-tear was detected
in 20 of 62 patients (32%) assessed with ultrasound. Age at operation We conclude that arthroscopic rotator cuff repair in patients
aged ≥ 70 years is a successful procedure. The gender and age of
the patient are important factors to consider when planning management. Cite this article:
Bone surface strains were measured in cadaver femora during loading prior to and after resurfacing of the hip and total hip replacement using an uncemented, tapered femoral component. In vitro loading simulated the single-leg stance phase during walking. Strains were measured on the medial and the lateral sides of the proximal aspect and the mid-diaphysis of the femur. Bone surface strains following femoral resurfacing were similar to those in the native femur, except for proximal shear strains, which were significantly less than those in the native femur. Proximomedial strains following total hip replacement were significantly less than those in the native and the resurfaced femur. These results are consistent with previous clinical evidence of bone loss after total hip replacement, and provide support for claims of bone preservation after resurfacing arthroplasty of the hip.
Femoroacetabular impingement causes groin pain
and decreased athletic performance in active adults. This bony conflict
may result in femoroacetabular subluxation if of sufficient magnitude. The ligamentum teres has recently been reported to be capable
of withstanding tensile loads similar to that of the anterior cruciate
ligament, and patents with early subluxation of the hip may become
dependent on the secondary restraint that is potentially provided
by the ligamentum teres. Rupture of the ligamentum may thus cause
symptomatic hip instability during athletic activities. An arthroscopic reconstruction of the ligamentum teres using
iliotibial band autograft was performed in an attempt to restore
this static stabiliser in a series of four such patients. Early
clinical results have been promising. The indications, technique
and early outcomes of this procedure are discussed.
Several aspects of the management of an orthopaedic surgical patient are not directly related to the surgical technique but are nevertheless essential for a successful outcome. Blood management is one of these. This paper considers the various strategies available for the management of blood loss in patients undergoing orthopaedic and trauma surgery.
In this study we present our experience with
four generations of uncemented total knee arthroplasty (TKA) from Smith
&
Nephew: Tricon M, Tricon LS, Tricon II and Profix, focusing
on the failure rates correlating with each design change. Beginning
in 1984, 380 Tricon M, 435 Tricon LS, 305 Tricon 2 and 588 Profix
were implanted by the senior author. The rate of revision for loosening
was 1.1% for the Tricon M, 1.1% for the Tricon LS, 0.5% for the
Tricon 2 with a HA coated tibial component, and 1.3% for the Profix
TKA. No loosening of the femoral component was seen with the Tricon
M, Tricon LS or Tricon 2, with no loosening seen of the tibial component
with the Profix TKA. Regarding revision for wear, the incidence
was 13.1% for the Tricon M, 6.6% for the Tricon LS, 2.3% for the
Tricon 2, and 0% for the Profix. These results demonstrate that
improvements in the design of uncemented components, including increased
polyethylene thickness, improved polyethylene quality, and the introduction
of hydroxyapatite coating, has improved the outcomes of uncemented
TKA over time.
The aim of this study was to determine the association
between the Oxford knee score (OKS) and direct assessment of outcome,
and to examine how this relationship varied at different time-points
following total knee replacement (TKR). Prospective data consisting
of the OKS, numerical rating scales for ‘worst pain’ and ‘perceived
mean daily pain’, timed functional assessments (chair rising, stairs
and walking ability), goniometry and lower limb power were recorded
for 183 patients pre-operatively and at six, 26 and 52 weeks post-operatively.
The OKS was influenced primarily by the patient’s level of pain
rather than objective functional assessments. The relationship between report
of outcome and direct assessment changed over time: R2 =
35% pre-operatively, 44% at six weeks, 57% at 26 weeks and 62% at
52 weeks. The relationship between assessment of performance and report
of performance improved as the patient’s report of pain diminished,
suggesting that patients’ reporting of functional outcome after
TKR is influenced more by their pain level than their ability to
accomplish tasks.
Venous thromboembolism (VTE) remains an immediate
threat to patients following total hip and knee replacement. While
there is a strong consensus that steps should be taken to minimise
the risk to patients by utilising some forms of prophylaxis for
the vast majority of patients, the methods utilised have been extremely
variable. Clinical practice guidelines (CPGs) have been published
by various professional organisations for over 25 years to provide recommendations
to standardise VTE prophylaxis. Historically, these recommendations
have varied widely depending in underlying assumptions, goals, and
methodology of the various groups. This effort has previously been
exemplified by the American College of Chest Physicians (ACCP) and
the American Academy of Orthopaedic Surgeons (AAOS). The former
group of medical specialists targeted minimising venographically
proven deep vein thrombosis (DVT) (the vast majority of which are
asymptomatic) as their primary goal prior to 2012. The latter group of
surgeons targeted minimising symptomatic VTE. As a result prior
to 2012, the recommendations of the two groups were widely divergent.
In the past year, both groups have reassessed the current literature
with the principal goals of minimising symptomatic VTE events and
bleeding complications. As a result, for the first time the CPGs
of these two major subspecialty organisations are in close agreement.
The October 2012 Research Roundup360 looks at: whether you can escape your genes; oral prophylaxis for DVT; non-responders and the internet; metal-on-metal, mice and damaged livers; sleeping on the job; cartilage contact stress in the normal human hip; and a perfect reason to subscribe to
The October 2012 Shoulder &
Elbow Roundup360 looks at: fast-absorbing suture anchors for use in shoulder labral tears; double-row rotator cuff repair; degenerate massive rotator cuff tears addressed with partial repair; open and arthroscopic stabilisation of Bankart lesions; predicting the risk of revision humeral head replacement; arthroscopic treatment for frozen shoulder; and long-term follow-up of the Bristow-Latarjet procedure.
The Oxford knee score (OKS) is a validated and
widely accepted disease-specific patient-reported outcome measure,
but there is limited evidence regarding any long-term trends in
the score. We reviewed 5600 individual OKS questionnaires (1547
patients) from a prospectively-collected knee replacement database,
to determine the trends in OKS over a ten-year period following
total knee replacement. The mean OKS pre-operatively was 19.5 (95%
confidence interval (CI) 18.8 to 20.2). The maximum post-operative
OKS was observed at two years (mean score 34.4 (95% CI 33.7 to 35.2)),
following which a gradual but significant decline was observed through
to the ten-year assessment (mean score 30.1 (95% CI 29.1 to 31.1))
(p <
0.001). A similar trend was observed for most of the individual
OKS components (p <
0.001). Kneeling ability initially improved
in the first year but was then followed by rapid deterioration (p
<
0.001). Pain severity exhibited the greatest improvement, although
residual pain was reported in over two-thirds of patients post-operatively,
and peak improvement in the night pain component did not occur until
year four. Post-operative OKS was lower for women (p <
0.001),
those aged <
60 years (p <
0.003) and those with a body mass
index >
35 kg/m2 (p <
0.014), although similar changes
in scores were observed. This information may assist surgeons in
advising patients of their expected outcomes, as well as providing
a comparative benchmark for evaluating longer-term outcomes following
knee replacement. Cite this article:
We retrospectively analysed concentrations of chromium and cobalt ions in samples of synovial fluid and whole blood taken from a group of 92 patients with failed current-generation metal-on-metal hip replacements. We applied acid oxidative digestion to our trace metal analysis protocol, which found significantly higher levels of metal ion concentrations in blood and synovial fluid than a non-digestive method. Patients were subcategorised by mode of failure as either ‘unexplained pain’ or ‘defined causes’. Using this classification, chromium and cobalt ion levels were present over a wider range in synovial fluid and not as strongly correlated with blood ion levels as previously reported. There was no significant difference between metal ion concentrations and manufacturer of the implant, nor femoral head size below or above 50 mm. There was a moderately positive correlation between metal ion levels and acetabular component inclination angle as measured on three-dimensional CT imaging. Our results suggest that acid digestion of samples of synovial fluid samples is necessary to determine metal ion concentrations accurately so that meaningful comparisons can be made between studies.
The October 2012 Hip &
Pelvis Roundup360 looks at: diagnosing the infected hip replacement; whether tranexamic acid has a low complication rate; the relationship between poor cementing technique and early failure of resurfacing; debridement and retention for the infected replacement; triple-tapered stems and bone mineral density; how early discharge can be bad for your sleep; an updated QFracture algorithm to predict the risk of an osteoporotic fracture; and local infiltration analgesia and total hip replacement.
Compression and absolute stability are important in the management of intra-articular fractures. We compared tension band wiring with plate fixation for the treatment of fractures of the olecranon by measuring compression within the fracture. Identical transverse fractures were created in models of the ulna. Tension band wires were applied to ten fractures and ten were fixed with Acumed plates. Compression was measured using a Tekscan force transducer within the fracture gap. Dynamic testing was carried out by reproducing cyclical contraction of the triceps of 20 N and of the brachialis of 10 N. Both methods were tested on each sample. Paired The mean compression for plating was 819 N ( During simulated movements, the mean compression was reduced in both groups, with tension band wiring at −14 N ( Pre-contoured plates provide significantly greater compression than tension bands in the treatment of transverse fractures of the olecranon, both over the whole fracture and specifically at the articular side of the fracture. In tension band wiring the overall compression was reduced and articular compression remained negligible during simulated contraction of the triceps, challenging the tension band principle.
The fracture most commonly treated by orthopaedic surgeons is that of the distal radius. However, as yet there is no consensus on what constitutes an ‘acceptable’ radiological position before or after treatment. This should be defined as the position that will predict good function in the majority of cases. In this paper we review the radiological indices that can be measured in fractures of the distal radius and try to identify potential predictors of functional outcome. In patients likely to have high functional demands, we recommend that the articular reconstruction be achieved with less than 2 mm of gap or step-off, the radius be restored to within 2 mm of its normal length, and that carpal alignment be restored. The ultimate aim of treatment is a pain-free, mobile wrist joint without functional limitation.
Matrix-assisted autologous chondrocyte transplantation (MACT)
has been developed and applied in the clinical practice in the last
decade to overcome most of the disadvantages of the first generation
procedures. The purpose of this systematic review is to document
and analyse the available literature on the results of MACT in the
treatment of chondral and osteochondral lesions of the knee. All studies published in English addressing MACT procedures were
identified, including those that fulfilled the following criteria:
1) level I-IV evidence, 2) measures of functional or clinical outcome,
3) outcome related to cartilage lesions of the knee cartilage.Objectives
Methods
Bacterial infection in orthopaedic surgery can be devastating, and is associated with significant morbidity and poor functional outcomes, which may be improved if high concentrations of antibiotics can be delivered locally over a prolonged period of time. The two most widely used methods of doing this involve antibiotic-loaded polymethylmethacrylate or collagen fleece. The former is not biodegradable and is a surface upon which secondary bacterial infection may occur. Consequently, it has to be removed once treatment has finished. The latter has been used successfully as an adjunct to systemic antibiotics, but cannot effect a sustained release that would allow it to be used on its own, thereby avoiding systemic toxicity. This review explores the newer biodegradable carrier systems which are currently in the experimental phase of development and which may prove to be more effective in the treatment of osteomyelitis.
Wear of polyethylene is associated with aseptic loosening of orthopaedic implants and has been observed in hip and knee prostheses and anatomical implants for the shoulder. The reversed shoulder prostheses have not been assessed as yet. We investigated the volumetric polyethylene wear of the reversed and anatomical Aequalis shoulder prostheses using a mathematical musculoskeletal model. Movement and joint stability were achieved by EMG-controlled activation of the muscles. A non-constant wear factor was considered. Simulated activities of daily living were estimated from After one year of use, the volumetric wear was 8.4 mm3 for the anatomical prosthesis, but 44.6 mm3 for the reversed version. For the anatomical prosthesis the predictions for contact pressure and wear were consistent with biomechanical and clinical data. The abrasive wear of the polyethylene in reversed prostheses should not be underestimated, and further analysis, both experimental and clinical, is required.
This study was designed to test the hypothesis
that the sensory innervation of bone might play an important role
in sensing and responding to low-intensity pulsed ultrasound and
explain its effect in promoting fracture healing. In 112 rats a
standardised mid-shaft tibial fracture was created, supported with
an intramedullary needle and divided into four groups of 28. These
either had a sciatic neurectomy or a patellar tendon resection as
control, and received the ultrasound or not as a sham treatment.
Fracture union, callus mineralisation and remodelling were assessed using
plain radiography, peripheral quantitative computed tomography and
histomorphology. Daily ultrasound treatment significantly increased the rate of
union and the volumetric bone mineral density in the fracture callus
in the neurally intact rats (p = 0.025), but this stimulating effect
was absent in the rats with sciatic neurectomy. Histomorphology
demonstrated faster maturation of the callus in the group treated
with ultrasound when compared with the control group. The results
supported the hypothesis that intact innervation plays an important
role in allowing low-intensity pulsed ultrasound to promote fracture
healing.
Radiostereometric analysis (RSA) can detect early
micromovement in unstable implant designs which are likely subsequently
to have a high failure rate. In 2010, the Articular Surface Replacement
(ASR) was withdrawn because of a high failure rate. In 19 ASR femoral
components, the mean micromovement over the first two years after implantation
was 0.107 mm ( We conclude that the ASR femoral component achieves initial stability
and that early migration is not the mode of failure for this resurfacing
arthroplasty.