Hyaline articular cartilage has been known to
be a troublesome tissue to repair once damaged. Since the introduction
of autologous chondrocyte implantation (ACI) in 1994, a renewed
interest in the field of cartilage repair with new repair techniques
and the hope for products that are regenerative have blossomed.
This article reviews the basic science structure and function of
articular cartilage, and techniques that are presently available
to effect repair and their expected outcomes.
Achieving deep flexion after total knee replacement remains a challenge. In this study we compared the soft-tissue tension and tibiofemoral force in a mobile-bearing posterior cruciate ligament-sacrificing total knee replacement, using equal flexion and extension gaps, and with the gaps increased by 2 mm each. The tests were conducted during passive movement in five cadaver knees, and measurements of strain were made simultaneously in the collateral ligaments. The tibiofemoral force was measured using a customised mini-force plate in the tibial tray. Measurements of collateral ligament strain were not very sensitive to changes in the gap ratio, but tibiofemoral force measurements were. Tibiofemoral force was decreased by a mean of 40% (
The August 2012 Wrist &
Hand Roundup360 looks at: the Herbert ulnar head prosthesis; the five-year outcome for wrist arthroscopic surgery; four-corner arthrodesis with headless screws; balloon kyphoplasty for Kienböck's disease; Mason Type 2 radial head fractures; local infiltration and intravenous regional anaesthesia for endoscopic carpal tunnel release; perilunate injuries; and replanting the amputated fingertip.
We prospectively assessed the benefits of using either a range-of-movement technique or an anatomical landmark method to determine the rotational alignment of the tibial component during total knee replacement. We analysed the cut proximal tibia intraoperatively, determining anteroposterior axes by the range-of-movement technique and comparing them with the anatomical anteroposterior axis. We found that the range-of-movement technique tended to leave the tibial component more internally rotated than when anatomical landmarks were used. In addition, it gave widely variable results (mean 7.5°; 2° to 17°), determined to some extent by which posterior reference point was used. Because of the wide variability and the possibilities for error, we consider that it is inappropriate to use the range-of-movement technique as the sole method of determining alignment of the tibial component during total knee replacement.
The purpose of this study was to evaluate chronological changes
in the collagen-type composition at tendon–bone interface during
tendon–bone healing and to clarify the continuity between Sharpey-like
fibres and inner fibres of the tendon. Male white rabbits were used to create an extra-articular bone–tendon
graft model by grafting the extensor digitorum longus into a bone
tunnel. Three rabbits were killed at two, four, eight, 12 and 26
weeks post-operatively. Elastica van Gieson staining was used to colour
5 µm coronal sections, which were examined under optical and polarised
light microscopy. Immunostaining for type I, II and III collagen
was also performed.Objectives
Methods
We report the clinical and radiological results of a two- to three-year prospective randomised study which was designed to compare a minimally-invasive technique with a standard technique in total knee replacement and was undertaken between January 2004 and May 2007. The mini-midvastus approach was used on 50 patients (group A) and a standard approach on 50 patients (group B). The mean follow-up in both groups was 23 months (24 to 35). The functional outcome was better in group A up to nine months after operation, as shown by statistically significant differences in the mean function score, mean total score and the mean Oxford knee score (all, p = 0.05). Patients in group A had statistically significant greater early flexion (p = 0.04) and reached their greatest mean knee flexion of 126.5° (95° to 135°) 21 days after operation. However, at final follow-up there was no significant difference in the mean maximum flexion between the groups (p = 0.08). Technical errors were identified in six patients from group A (12%) on radiological evaluation. Based on these results, the authors currently use minimally-invasive techniques in total knee replacement in selected cases only.
A total of 445 consecutive primary total knee
replacements (TKRs) were followed up prospectively at six and 18 months
and three, six and nine years. Patients were divided into two groups:
non-obese (body mass index (BMI) <
30 kg/m2) and obese
(BMI ≥ 30 kg/m2). The obese group was subdivided into
mildly obese (BMI 30 to 35 kg/m2) and highly obese (BMI ≥ 35
kg/m2) in order to determine the effects of increasing
obesity on outcome. The clinical data analysed included the Knee
Society score, peri-operative complications and implant survival.
There was no difference in the overall complication rates or implant
survival between the two groups. Obesity appears to have a small but significant adverse effect
on clinical outcome, with highly obese patients showing lower function
scores than non-obese patients. However, significant improvements
in outcome are sustained in all groups nine years after TKR. Given
the substantial, sustainable relief of symptoms after TKR and the low
peri-operative complication and revision rates in these two groups,
we have found no reason to limit access to TKR in obese patients.
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
Seven stiff total knee arthroplasties are presented
to illustrate the roles of: 1) manipulation under general anesthesia;
2) multiple concurrent diagnoses in addition to stiffness; 3) extra-articular
pathology; 4) pain as part of the stiffness triad (pain and limits
to flexion or extension); 5) component internal rotation; 6) multifactorial
etiology; and 7) surgical exposure in this challenging clinical
problem.
The lateral compartment is predominantly affected
in approximately 10% of patients with osteoarthritis of the knee. The
anatomy, kinematics and loading during movement differ considerably
between medial and lateral compartments of the knee. This in the
main explains the relative protection of the lateral compartment
compared with the medial compartment in the development of osteoarthritis.
The aetiology of lateral compartment osteoarthritis can be idiopathic,
usually affecting the femur, or secondary to trauma commonly affecting
the tibia. Surgical management of lateral compartment osteoarthritis
can include osteotomy, unicompartmental knee replacement and total
knee replacement. This review discusses the biomechanics, pathogenesis
and development of lateral compartment osteoarthritis and its management. Cite this article:
Radiological assessment of total and unicompartmental
knee replacement remains an essential part of routine care and follow-up.
Appreciation of the various measurements that can be identified
radiologically is important. It is likely that routine plain radiographs
will continue to be used, although there has been a trend towards
using newer technologies such as CT, especially in a failing knee,
where it provides more detailed information, albeit with a higher
radiation exposure. The purpose of this paper is to outline the radiological parameters
used to evaluate knee replacements, describe how these are measured
or classified, and review the current literature to determine their
efficacy where possible.
The menisci of the knee have an important role in load-bearing and shock absorption within the joint. They may also function as secondary stabilisers, have a proprioceptive role, and aid the lubrication and nutrition of the articular cartilage. Complete or partial loss of a meniscus can have damaging effects on a knee, leading to serious long-term sequelae. This paper reviews the consequences of meniscectomy and summarises the body of evidence in the literature regarding those factors most relevant to long-term outcome.
This review considers the surgical treatment
of displaced fractures involving the knee in elderly, osteoporotic patients.
The goals of treatment include pain control, early mobilisation,
avoidance of complications and minimising the need for further surgery.
Open reduction and internal fixation (ORIF) frequently results in
loss of reduction, which can result in post-traumatic arthritis
and the occasional conversion to total knee replacement (TKR). TKR
after failed internal fixation is challenging, with modest functional
outcomes and high complication rates. TKR undertaken as treatment
of the initial fracture has better results to late TKR, but does
not match the outcome of primary TKR without complications. Given
the relatively infrequent need for late TKR following failed fixation,
ORIF is the preferred management for most cases. Early TKR can be
considered for those patients with pre-existing arthritis, bicondylar
femoral fractures, those who would be unable to comply with weight-bearing restrictions,
or where a single definitive procedure is required.
Autologous chondrocyte implantation (ACI) and
mosaicplasty are methods of treating symptomatic articular cartilage
defects in the knee. This study represents the first long-term randomised
comparison of the two techniques in 100 patients at a minimum follow-up
of ten years. The mean age of the patients at the time of surgery was
31.3 years (16 to 49); the mean duration of symptoms pre-operatively
was 7.2 years (9 months to 20 years). The lesions were large with
the mean size for the ACI group being 440.9 mm2 (100
to 1050) and the mosaicplasty group being 399.6 mm2 (100
to 2000). Patients had a mean of 1.5 previous operations (0 to 4)
to the articular cartilage defect. Patients were assessed using
the modified Cincinnati knee score and the Stanmore-Bentley Functional Rating
system. The number of patients whose repair had failed at ten years
was ten of 58 (17%) in the ACI group and 23 of 42 (55%) in the mosaicplasty
group (p <
0.001). The functional outcome of those patients with a surviving graft
was significantly better in patients who underwent ACI compared
with mosaicplasty (p = 0.02).
This review describes the development of arthroscopy of the hip over the past 15 years with reference to patient assessment and selection, the technique, the conditions for which it is likely to prove useful, the contraindications and complications related to the procedure and, finally, to discuss possible developments in the future.
The aim of this prospective single-centre study
was to assess the difference in clinical outcome between total knee replacement
(TKR) using computerised navigation and that of conventional TKR.
We hypothesised that navigation would give a better result at every
stage within the first five years. A total of 195 patients (195
knees) with a mean age of 70.0 years (39 to 89) were allocated alternately
into two treatment groups, which used either conventional instrumentation
(group A, 97 knees) or a navigation system (group B, 98 knees).
After five years, complete clinical scores were available for 121
patients (62%). A total of 18 patients were lost to follow-up. Compared
with conventional surgery, navigated TKR resulted in a better mean
Knee Society score (p = 0.008). The difference in mean Knee Society
scores over time between the two groups was not constant (p = 0.006),
which suggests that these groups differed in their response to surgery
with time. No significant difference in the frequency of malalignment
was seen between the two groups. In summary, computerised navigation resulted in a better functional
outcome at five years than conventional techniques. Given the similarity
in mechanical alignment between the two groups, rotational alignment
may prove to be a better method of identifying differences in clinical
outcome after navigated surgery.
We retrospectively reviewed the records of 1150
computer-assisted total knee replacements and analysed the clinical
and radiological outcomes of 45 knees that had arthritis with a
pre-operative recurvatum deformity. The mean pre-operative hyperextension
deformity of 11° (6° to 15°), as measured by navigation at the start
of the operation, improved to a mean flexion deformity of 3.1° (0°
to 7°) post-operatively. A total of 41 knees (91%) were managed
using inserts ≤ 12.5 mm thick, and none had mediolateral laxity
>
2 mm from a mechanical axis of 0° at the end of the surgery. At
a mean follow-up of 26.4 months (13 to 48) there was significant
improvement in the mean Knee Society, Oxford knee and Western Ontario
and McMaster Universities Osteoarthritis Index scores compared with
the pre-operative values. The mean knee flexion improved from 105°
(80° to 125°) pre-operatively to 131° (120° to 145°), and none of
the limbs had recurrent recurvatum. These early results show that total knee replacement using computer
navigation and an algorithmic approach for arthritic knees with
a recurvatum deformity can give excellent radiological and functional
outcomes without recurrent deformity.
Injury to the sciatic nerve following closed manipulation of a dislocated total hip replacement is rare. We present such a case in an elderly patient with partial recovery following exploration and release of the nerve.
A displaced fracture of the scaphoid is one in
which the fragments have moved from their anatomical position or there
is movement between them when stressed by physiological loads. Displacement
is seen in about 20% of fractures of the waist of the scaphoid,
as shown by translation, a gap, angulation or rotation. A CT scan
in the true longitudinal axis of the scaphoid demonstrates the shape
of the bone and displacement of the fracture more accurately than
do plain radiographs. Displaced fractures can be treated in a plaster
cast, accepting the risk of malunion and nonunion. Surgically the
displacement can be reduced, checked radiologically, arthroscopically
or visually, and stabilised with headless screws or wires. However,
rates of union and deformity are unknown. Mild malunion is well
tolerated, but the long-term outcome of a displaced fracture that
healed in malalignment has not been established. This paper summarises aspects of the assessment, treatment and
outcome of displaced fractures of the waist of the scaphoid.
This study compared the outcome of total knee
replacement (TKR) in adult patients with fixed- and mobile-bearing prostheses
during the first post-operative year and at five years’ follow-up,
using gait parameters as a new objective measure. This double-blind
randomised controlled clinical trial included 55 patients with mobile-bearing (n
= 26) and fixed-bearing (n = 29) prostheses of the same design,
evaluated pre-operatively and post-operatively at six weeks, three
months, six months, one year and five years. Each participant undertook
two walking trials of 30 m and completed the EuroQol questionnaire,
Western Ontario and McMaster Universities osteoarthritis index,
Knee Society score, and visual analogue scales for pain and stiffness.
Gait analysis was performed using five miniature angular rate sensors
mounted on the trunk (sacrum), each thigh and calf. The study population
was divided into two groups according to age (≤ 70 years Improvements in most gait parameters at five years’ follow-up
were greater for fixed-bearing TKRs in older patients (>
70 years),
and greater for mobile-bearing TKRs in younger patients (≤ 70 years).
These findings should be confirmed by an extended age controlled
study, as the ideal choice of prosthesis might depend on the age
of the patient at the time of surgery.