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.
The April 2015 Shoulder &
Elbow Roundup360 looks at: Distal clavicular resection not indicated in cuff repair?; Platelet-rich plasma in rotator cuff repair; Radial head geometry: time to change?; Heterotopic ossification in elbow trauma; Another look at heterotopic ossification in the humerus; Triceps on for total elbow arthroplasty?; Predicting outcomes in rotator cuff repair; Deltoid fatty infiltration and reverse shoulder arthroplasty
Talonavicular and subtalar joint fusion through
a medial incision (modified triple arthrodesis) has become an increasingly
popular technique for treating symptomatic flatfoot deformity caused
by posterior tibial tendon dysfunction. The purpose of this study was to look at its clinical and radiological
mid- to long-term outcomes, including the rates of recurrent flatfoot
deformity, nonunion and avascular necrosis of the dome of the talus. A total of 84 patients (96 feet) with a symptomatic rigid flatfoot
deformity caused by posterior tibial tendon dysfunction were treated
using a modified triple arthrodesis. The mean age of the patients
was 66 years (35 to 85) and the mean follow-up was 4.7 years (1 to 8.3).
Both clinical and radiological outcomes were analysed retrospectively. In 86 of the 95 feet (90.5%) for which radiographs were available,
there was no loss of correction at final follow-up. In all, 14 feet
(14.7%) needed secondary surgery, six for nonunion, two for avascular
necrosis, five for progression of the flatfoot deformity and tibiotalar
arthritis and one because of symptomatic overcorrection. The mean
American Orthopaedic Foot and Ankle Society Hindfoot score (AOFAS
score) at final follow-up was 67 (between 16 and 100) and the mean
visual analogue score for pain 2.4 points (between 0 and 10). In conclusion, modified triple arthrodesis provides reliable
correction of deformity and a good clinical outcome at mid- to long-term
follow-up, with nonunion as the most frequent complication. Avascular
necrosis of the talus is a rare but serious complication of this
technique. Cite this article:
The April 2015 Wrist &
Hand Roundup360 looks at: Non-operative hand fracture management; From the sublime to the ridiculous?; A novel approach to carpal tunnel decompression; Osteoporosis and functional scores in the distal radius; Ulnar variance and force distribution; Tourniquets in carpal tunnel under the spotlight; Scaphoid fractures reclassified; Osteoporosis and distal radial fracture fixation; PROMISing results in the upper limb
The aim of this study was to compare the maximum
laxity conferred by the cruciate-retaining (CR) and posterior-stabilised
(PS) Triathlon single-radius total knee arthroplasty (TKA) for anterior
drawer, varus–valgus opening and rotation in eight cadaver knees
through a defined arc of flexion (0º to 110º). The null hypothesis
was that the limits of laxity of CR- and PS-TKAs are not significantly
different. The investigation was undertaken in eight loaded cadaver knees
undergoing subjective stress testing using a measurement rig. Firstly
the native knee was tested prior to preparation for CR-TKA and subsequently
for PS-TKA implantation. Surgical navigation was used to track maximal
displacements/rotations at 0º, 30º, 60º, 90º and 110° of flexion.
Mixed-effects modelling was used to define the behaviour of the
TKAs. The laxity measured for the CR- and PS-TKAs revealed no statistically
significant differences over the studied flexion arc for the two
versions of TKA. Compared with the native knee both TKAs exhibited
slightly increased anterior drawer and decreased varus-valgus and
internal-external roational laxities. We believe further study is required
to define the clinical states for which the additional constraint
offered by a PS-TKA implant may be beneficial. Cite this article:
The April 2014 Wrist &
Hand Roundup360 looks at: diagnosis of compressive neuropathy; relevant reviews; the biomechanics of dorsal PIP fracture dislocation; the more strands the better; and state of mind the best predictor of outcome.
A high radiographic inclination angle (RI) contributes
to accelerated wear and has been associated with dislocation after
total hip arthroplasty (THA). With freehand positioning of the acetabular
component there is a lack of accuracy, with a trend towards a high
radiographic inclination angle. The aim of this study was to investigate
whether the use of a digital protractor to measure the operative
inclination angle (OI) could improve the positioning of the acetabular
component in relation to a ‘safe zone’. We measured the radiographic inclination angles of 200 consecutive
uncemented primary THAs. In the first 100 the component was introduced
freehand and in the second 100 a digital protractor was used to
measure the operative inclination angle. The mean difference between the operative and the radiographic
inclination angles
(∆RI–OI) in the second cohort was 12.3° (3.8° to 19.8°). There was
a strong correlation between the circumference of the hip and ∆RI–OI.
The number of RI outliers was significantly reduced in the protractor
group (p = 0.002). Adjusting the OI, using a digital protractor and taking into
account the circumference of the patient’s hip, improves the RI
significantly (p <
0.001) and does not require additional operating
time. Cite this article:
Initial stability of tibial trays is crucial for long-term success of total knee arthroplasty (TKA) in both primary and revision settings. Rotating platform (RP) designs reduce torque transfer at the tibiofemoral interface. We asked if this reduced torque transfer in RP designs resulted in subsequently reduced micromotion at the cemented fixation interface between the prosthesis component and the adjacent bone. Composite tibias were implanted with fixed and RP primary and revision tibial trays and biomechanically tested under up to 2.5 kN of axial compression and 10° of external femoral component rotation. Relative micromotion between the implanted tibial tray and the neighbouring bone was quantified using high-precision digital image correlation techniques.Objectives
Methods
Reported rates of dislocation in hip hemiarthroplasty
(HA) for the treatment of intra-capsular fractures of the hip, range
between 1% and 10%. HA is frequently performed through a direct
lateral surgical approach. The aim of this study is to determine
the contribution of the anterior capsule to the stability of a cemented
HA through a direct lateral approach. A total of five whole-body cadavers were thawed at room temperature,
providing ten hip joints for investigation. A Thompson HA was cemented
in place via a direct lateral approach. The cadavers were then positioned
supine, both knee joints were disarticulated and a digital torque
wrench was attached to the femur using a circular frame with three
half pins. The wrench applied an external rotation force with the
hip in extension to allow the hip to dislocate anteriorly. Each
hip was dislocated twice; once with a capsular repair and once without
repairing the capsule. Stratified sampling ensured the order in
which this was performed was alternated for the paired hips on each
cadaver. Comparing peak torque force in hips with the capsule repaired
and peak torque force in hips without repair of the capsule, revealed
a significant difference between the ‘capsule repaired’ (mean 22.96
Nm, standard deviation ( Cite this article:
The December 2014 Foot &
Ankle Roundup360 looks at: Charcot feet, biomarkers and diabetes; weight bearing following Achilles tendon rupture; endobuttons and mal-reduced diastasis; evidence for stem cell therapies in osteochondral lesions of the talus; syndesmosis fixation in SER ankle fractures; and self-reporting for foot and ankle outcomes.
We have reviewed the current literature to compare
the results of surgery aimed to repair or debride a damaged acetabular
labrum. We identified 28 studies to be included in the review containing
a total of 1631 hips in 1609 patients. Of these studies 12 reported
a mean rate of good results of 82% (from 67% to 100%) for labral debridement.
Of the 16 studies that reported a combination of debridement and
re-attachment, five reported a comparative outcome for the two methods,
four reported better results with re-attachment and one study did
not find any significant difference in outcomes. Due to the heterogeneity
of the studies it was not possible to perform a meta-analysis or
draw accurate conclusions. Confounding factors in the studies include
selection bias, use of historical controls and high rates of loss
of follow-up. It seems logical to repair an unstable tear in a good quality
labrum with good potential to heal in order potentially to preserve
its physiological function. A degenerative labrum on the other hand
may be the source of discomfort and its preservation may result
in persistent pain and the added risk of failure of re-attachment.
The results of the present study do not support routine refixation
for all labral tears. Cite this article:
The October 2014 Foot &
Ankle Roundup360 looks at: multilayer compression bandaging superior for post-traumatic ankle oedema; compression stockings for ankle fractures; weight bearing ok in Achilles tendon ruptures; MRI findings can predict ankle sprain symptoms; salvage for malreduced ankle fractures; locking fibular plates are more expensive; is fixation better early or late in pilon fractures?; and calcaneal fracture fixation not for subtalar arthropathy
Latissimus dorsi tendon transfer (LDTT) is technically
challenging. In order to clarify the local structural anatomy, we undertook
a morphometric study using six complete cadavers (12 shoulders).
Measurements were made from the tendon to the nearby neurovascular
structures with the arm in two positions: flexed and internally
rotated, and adducted in neutral rotation. The tendon was then transferred
and measurements were taken from the edge of the tendon to a reference
point on the humeral head in order to assess the effect of a novel
two-stage release on the excursion of the tendon. With the shoulder flexed and internally rotated, the mean distances
between the superior tendon edge and the radial nerve, brachial
artery, axillary nerve and posterior circumflex artery were 30 mm
(26 to 34), 28 mm (17 to 39), 21 mm (12 to 28) and 15 mm (10 to
21), respectively. The mean distance between the inferior tendon
edge and the radial nerve, brachial artery and profunda brachii
artery was 18 mm (8 to 27), 22 mm (15 to 32) and 14 mm (7 to 21), respectively.
Moving the arm to a neutral position reduced these distances. A
mean of 15 mm (8 to 21) was gained from a standard soft-tissue release,
and 32 mm (20 to 45) from an extensile release. These figures help to define further the structural anatomy of
this region and the potential for transfer of the latissimus dorsi
tendon. Cite this article:
It is becoming increasingly common for a patient
to have ipsilateral hip and knee replacements. The inter-prosthetic (IP)
distance, the distance between the tips of hip and knee prostheses,
has been thought to be associated with an increased risk of IP fracture.
Small gap distances are generally assumed to act as stress risers,
although there is no real biomechanical evidence to support this. The purpose of this study was to evaluate the influence of IP
distance, cortical thickness and bone mineral density on the likelihood
of an IP femoral fracture. A total of 18 human femur specimens were randomised into three
groups by bone density and cortical thickness. For each group, a
defined IP distance of 35 mm, 80 mm or 160 mm was created by choosing
the appropriate lengths of component. The maximum fracture strength
was determined using a four-point bending test. The fracture force of all three groups was similar (p = 0.498).
There was a highly significant correlation between the cortical
area and the fracture strength (r = 0.804, p <
0.001), whereas
bone density showed no influence. This study suggests that the IP distance has little influence
on fracture strength in IP femoral fractures: the thickness of the
cortex seems to be the decisive factor. Cite this article:
The August 2014 Shoulder &
Elbow Roundup360 looks at: Myofibroblasts perhaps not implicated in post-traumatic elbow stiffness; olecranon tip biomechanically sound for coranoid reconstruction; obesity and elbow replacement don’t mix; single column plating successful for extra-articular distal humeral fractures; satisfaction not predictable in frozen shoulder; tenodesis and repair both acceptable in Grade II SLAP tears; glenoid bone grafting is effective and glenohumeral articular lesions best seen with an arthroscope.
The August 2014 Wrist &
Hand Roundup360 looks at: Trapeziectomy superior to arthrodesis;
The October 2013 Wrist &
Hand Roundup360 looks at: Cost effectiveness of Dupuytren’s surgery; A 'new horizon' in distal radius imaging; Undisplaced means undisplaced; The mystery of the distal radial fracture continues; How thick is thick enough?: articular cartilage step off revisited; Is the midcarpal joint more important than we think?; Plates and Kirschner wires; Better early results with an IM nail?
The August 2014 Trauma Roundup360 looks at: On-table CT for calcaneal fractures; timing of femoral fracture surgery and outcomes; salvage arthroplasty for failed internal fixation of the femoral neck; screw insertion in osteoporotic bone; fibular intramedullary nailing on the ascendant; posterior wall acetabular fractures not all that innocent; bugs, plating and resistance and improving outcomes in olecranon tension band wiring.
Malpositioning of the trochanteric entry point
during the introduction of an intramedullary nail may cause iatrogenic
fracture or malreduction. Although the optimal point of insertion
in the coronal plane has been well described, positioning in the
sagittal plane is poorly defined. The paired femora from 374 cadavers were placed both in the anatomical
position and in internal rotation to neutralise femoral anteversion.
A marker was placed at the apparent apex of the greater trochanter,
and the lateral and anterior offsets from the axis of the femoral
shaft were measured on anteroposterior and lateral photographs. Greater
trochanteric morphology and trochanteric overhang were graded. The mean anterior offset of the apex of the trochanter relative
to the axis of the femoral shaft was 5.1 mm ( Placement of the entry position at the apex of the greater trochanter
in the anteroposterior view does not reliably centre an intramedullary
nail in the sagittal plane. Based on our findings, the site of insertion
should be about 5 mm posterior to the apex of the trochanter to
allow for its anterior offset. Cite this article:
We conducted an anatomical study to determine
the best technique for transfer of the anterior interosseous nerve (AIN)
for the treatment of proximal ulnar nerve injuries. The AIN, ulnar
nerve, and associated branches were dissected in 24 cadaver arms.
The number of branches of the AIN and length available for transfer
were measured. The nerve was divided just proximal to its termination
in pronator quadratus and transferred to the ulnar nerve through
the shortest available route. Separation of the deep and superficial
branches of the ulnar nerve by blunt dissection alone, was also
assessed. The mean number of AIN branches was 4.8 (3 to 8) and the
mean length of the nerve available for transfer was 72 mm (41 to
106). The transferred nerve reached the ulnar nerve most distally
when placed dorsal to flexor digitorum profundus (FDP). We therefore
conclude that the AIN should be passed dorsal to FDP, and that the
deep and superficial branches of the ulnar nerve require approximately
30 mm of blunt dissection and 20 mm of sharp dissection from the
point of bifurcation to the site of the anastomosis. The use of this technique for transfer of the AIN should improve
the outcome for patients with proximal ulnar nerve injuries. Cite this article: