The August 2012 Hip &
Pelvis Roundup360 looks at: whether cemented hip replacement might be bad for your health; highly cross-linked polyethylene; iHOT-33 - a new hip outcome measure; hamstring injuries; total hip replacement; stemmed metal-on-metal THR; bipolar hemiarthroplasty, neuromuscular disease and dislocation; the high risk of secondary hemiarthroplasty; and whether we have to repair the labrum after all?
The treatment of osteochondral lesions of the talus has evolved with the development of improved imaging and arthroscopic techniques. However, the outcome of treatment for large cystic type-V lesions is poor, using conventional grafting, debridement or microfracture techniques. This retrospective study examined the outcomes of 50 patients with a cystic talar defect who were treated with arthroscopically harvested, cored osteochondral graft taken from the ipsilateral knee. Of the 50 patients, 45 (90%) had a mean good to excellent score of 80.3 (52 to 90) in the Karlsson-Peterson Ankle Score, at a mean follow-up of 36 months (24 to 83). A malleolar osteotomy for exposure was needed in 26 patients and there were no malleolar mal- or nonunions. One patient had symptoms at the donor site three months after surgery; these resolved after arthroscopic release of scar tissue. This technique is demanding with or without a malleolar osteotomy, but if properly performed has a high likelihood of success.
The August 2012 Knee Roundup360 looks at: meniscal defects and a polyurethane scaffold; which is best between a single or double bundle; OA of the knee; how to resolve anterior knee pain; whether yoga can be bad for your menisci; metal ions in the serum; whether ACI is any good; the ACL; whether hyaluronic acid delays collagen degradation; and hyaluronan and patellar tendinopathy.
We reviewed 212 consecutive patients with adolescent
idiopathic scoliosis who underwent posterior spinal arthrodesis
using all pedicle screw instrumentation in terms of clinical, radiological
and Scoliosis Research Society (SRS)-22 outcomes. In Group 1 (51
patients), the correction was performed over two rods using bilateral
segmental pedicle screws. In Group 2 (161 patients), the correction
was performed over one rod using unilateral segmental pedicle screws
with the second rod providing stability of the construct
through two-level screw fixation at proximal and distal ends. The
mean age at surgery was
14.8 years in both groups. Comparison between groups showed no significant
differences with regard to age and Risser grade at surgery, pre-
and post-operative scoliosis angle, coronal Cobb correction, length
of hospital stay and SRS scores. Correction of upper thoracic curves
was significantly better in Group 1 (p = 0.02). Increased surgical time
and intra-operative blood loss was recorded in Group 1 (p <
0.001
and p = 0.04, respectively). The implant cost was reduced by mean
35% in Group 2 due to the lesser number of pedicle screws. Unilateral and bilateral pedicle screw techniques have both achieved
excellent deformity correction in adolescent patients with idiopathic
scoliosis, which was maintained at two-year follow-up. This has
been associated with high patient satisfaction and low complication
rates.
This review briefly summarises some of the definitive
studies of articular cartilage by microscopic MRI (µMRI) that were
conducted with the highest spatial resolutions. The article has
four major sections. The first section introduces the cartilage
tissue, MRI and µMRI, and the concept of image contrast in MRI.
The second section describes the characteristic profiles of three
relaxation times (T1, T2 and T1ρ)
and self-diffusion in healthy articular cartilage. The third section
discusses several factors that can influence the visualisation of
articular cartilage and the detection of cartilage lesion by MRI
and µMRI. These factors include image resolution, image analysis
strategies, visualisation of the total tissue, topographical variations
of the tissue properties, surface fibril ambiguity, deformation
of the articular cartilage, and cartilage lesion. The final section
justifies the values of multidisciplinary imaging that correlates
MRI with other technical modalities, such as optical imaging. Rather
than an exhaustive review to capture all activities in the literature,
the studies cited in this review are merely illustrative.
The identification of the extent of neural damage
in patients with acute or chronic spinal cord injury is imperative for
the accurate prediction of neurological recovery. The changes in
signal intensity shown on routine MRI sequences are of limited value
for predicting functional outcome. Diffusion tensor imaging (DTI)
is a novel radiological imaging technique which has the potential
to identify intact nerve fibre tracts, and has been used to image
the brain for a variety of conditions. DTI imaging of the spinal
cord is currently only a research tool, but preliminary studies
have shown that it holds considerable promise in predicting the
severity of spinal cord injury. This paper briefly reviews our current knowledge of this technique.
We performed a retrospective review of all patients
admitted to two large University Hospitals in the United Kingdom
over a 24-month period from January 2008 to January 2010 to identify
the incidence of atypical subtrochanteric and femoral shaft fractures
and their relationship to bisphosphonate treatment. Of the 3515 patients
with a fracture of the proximal femur, 156 fractures were in the
subtrochanteric region. There were 251 femoral shaft fractures.
The atypical fracture pattern was seen in 27 patients (7%) with
29 femoral shaft or subtrochanteric fractures. A total of 22 patients
with 24 atypical fractures were receiving bisphosphonate treatment at
the time of fracture. Prodromal pain was present in nine patients
(11 fractures); 11 (50%) of the patients on bisphosphonates suffered
12 spontaneous fractures, and healing of these fractures was delayed
in a number of patients. This large dual-centre review has established
the incidence of atypical femoral fractures at 7% of the study population,
81% of whom had been on bisphosphonate treatment for a mean of 4.6
years (0.04 to 12.1). This study does not advocate any change in the use of bisphosphonates
to prevent fragility fractures but attempts to raise awareness of
this possible problem so symptomatic patients will be appropriately
investigated. However, more work is required to identify the true
extent of this new and possibly increasing problem.
We report a prospective analysis of clinical
outcome in patients treated with medial patellofemoral ligament
(MPFL) reconstruction using an autologous semitendinosus graft.
The technique includes superolateral portal arthroscopic assessment
before and after graft placement to ensure correct graft tension
and patellar tracking before fixation. Between October 2005 and
October 2010, a total of 201 consecutive patients underwent 219 procedures.
Follow-up is presented for 211 procedures in 193 patients with a
mean age of 26 years (16 to 49), and mean follow-up of 16 months
(6 to 42). Indications were atraumatic recurrent patellar dislocation
in 141 patients, traumatic recurrent dislocation in 50, pain with
subluxation in 14 and a single dislocation with persistent instability
in six. There have been no recurrent dislocations/subluxations.
There was a statistically significant improvement between available pre-
and post-operative outcome scores for 193 patients (all p <
0.001).
Female patients with a history of atraumatic recurrent dislocation
and all patients with history of previous surgery had a significantly
worse outcome (all p <
0.05). The indication for surgery, degree
of dysplasia, associated patella alta, time from primary dislocation
to surgery and evidence of associated cartilage damage at operation
did not result in any significant difference in outcome. This series adds considerably to existing evidence that MPFL
reconstruction is an effective surgical procedure for selected patients
with patellofemoral instability.
It has been suggested that an increased posterior
tibial slope (PTS) and a narrow notch width index (NWI) increase
the risk of anterior cruciate ligament (ACL) injury. The aim of
this study was to establish why there are conflicting reports on
their significance. A total of fifty patients with a ruptured ACL
and 50 patients with an intact ACL were included in the study. The
group with ACL rupture had a statistically significantly increased
PTS (p <
0.001) and a smaller NWI (p <
0.001) than the control
group. When a high PTS and/or a narrow NWI were defined as risk
factors for an ACL rupture, 80% of patients had at least one risk
factor present; only 24% had both factors present. In both groups
the PTS was negatively correlated to the NWI (correlation coefficient
= -0.28, p = 0.0052). Using a univariate model, PTS and NWI appear
to be correlated to rupture of the ACL. Using a logistic regression
model, the PTS (p = 0.006) and the NWI (p <
0.0001) remain significant
risk factors. From these results, either a steep PTS or a narrow
NWI predisposes an individual to ACL injury. Future studies should
consider these factors in combination rather than in isolation.
Total hip replacement in patients with advanced osteonecrosis of the femoral head is often complicated by early loosening of the femoral component. Recent evidence has suggested that abnormal bone extending into the proximal femur may be responsible for the early failure of the femoral component. We aimed to identify which patients were at high risk of early failure by evaluating gadolinium-enhanced MR images of histologically-confirmed osteonecrotic lesions beyond the femoral head. Although the MR signal intensity has been shown to correlate well with osteonecrosis in the femoral head, it was found to be relatively insensitive at identifying lesions below the head, with a sensitivity of only 51% and a predictive value of a negative result of only 48%. However, the specificity was 90%, with the predictive value of a positive MRI finding being 86%. Only those patients with osteonecrosis of the femoral head secondary to sickle-cell disease, who are known to be at high risk of early loosening, had changes in the MR signal in the greater trochanter and the femoral shaft. This observation suggests that changes in the MR signal beyond the femoral head may represent osteonecrotic lesions in areas essential for the fixation of the femoral component. Pre-operative identification of such lesions in the neck of the femur may be important when considering hip resurfacing for osteonecrosis of the femoral head, following which early loosening of the femoral component and fracture of the neck are possible complications.
Osteoradionecrosis is a rare but recognised complication of radiotherapy. Cases have been described in the cervical spine following treatment for head and neck malignancies up to 25 years after administration of radiotherapy. We present a rare case of osteoradionecrosis affecting the L5 and S1 vertebral bodies in a 58-year-old woman who presented with low back pain 25 years after undergoing a hysterectomy with adjuvant radiotherapy for cancer of the cervix.
The purpose of this study was to assess N-acetyl aspartate changes
in the thalamus in patients with osteoarthritis of the hip using
proton magnetic resonance spectroscopy. Nine patients with osteoarthritis of the hip (symptomatic group,
nine women; mean age 61.4 years (48 to 78)) and nine healthy volunteers
(control group, six men, three women; mean age 30.0 years (26 to
38)) underwent proton magnetic resonance spectroscopy to assess
the changes of N-acetyl aspartate in the thalamus. Objectives
Methods
Pseudotumours (abnormal peri-prosthetic soft-tissue reactions)
following metal-on-metal hip resurfacing arthroplasty (MoMHRA) have
been associated with elevated metal ion levels, suggesting that
excessive wear may occur due to edge-loading of these MoM implants.
This study aimed to quantify The duration and magnitude of edge-loading Objectives
Methods
This pilot study analysed the outcome of open The mean age of the patients was 22.9 years (18 to 28) and the
mean follow-up was 28.7 months (24 to 36). There were no statistically
significant differences in regard to age of patients, cyst size
and the follow-up periods in the two groups. The operating time
and mean length of stay of group 2 patients was significantly shorter
than group 1 patients (p <
0.001). The time to healing was similar
in the two groups. The overall success rates for groups 1 and 2 were
92.3% (12 of 13) and 100% (13 of 13), respectively, and there were
no statistically significant differences regarding radiological
healing. This pilot study suggests that endoscopic curettage and
percutaneous grafting is a simple and safe form of treatment, with
similar results to those following open treatment.
Peri-articular soft-tissue masses or ‘pseudotumours’
can occur after large-diameter metal-on-metal (MoM) resurfacing
of the hip and conventional total hip replacement (THR). Our aim
was to assess the incidence of pseudotumour formation and to identify
risk factors for their formation in a prospective cohort study. A total of 119 patients who underwent 120 MoM THRs with large-diameter
femoral heads between January 2005 and November 2007 were included
in the study. Outcome scores, serum metal ion levels, radiographs
and CT scans were obtained. Patients with symptoms or an identified
pseudotumour were offered MRI and an ultrasound-guided biopsy. There were 108 patients (109 hips) eligible for evaluation by
CT scan at a mean follow-up of 3.6 years (2.5 to 4.5); 42 patients
(39%) were diagnosed with a pseudotumour. The hips of 13 patients
(12%) were revised to a polyethylene acetabular component with small-diameter
metal head. Patients with elevated serum metal ion levels had a
four times increased risk of developing a pseudotumour. This study shows a substantially higher incidence of pseudotumour
formation and subsequent revisions in patients with MoM THRs than
previously reported. Because most revision cases were identified
only after an intensive screening protocol, we recommend close monitoring
of patients with MoM THR.
We retrospectively examined the prevalence and
natural history of asymptomatic lumbar canal stenosis in patients treated
surgically for cervical compressive myelopathy in order to assess
the influence of latent lumbar canal stenosis on the recovery after
surgery. Of 214 patients who had undergone cervical laminoplasty
for cervical myelopathy, we identified 69 (32%) with myelographically
documented lumbar canal stenosis. Of these, 28 (13%) patients with
symptomatic lumbar canal stenosis underwent simultaneous cervical
and lumbar decompression. Of the remaining 41 (19%) patients with
asymptomatic lumbar canal stenosis who underwent only cervical surgery,
39 were followed up for ≥ 1 year (mean 4.9 years (1 to 12)) and
were included in the analysis (study group). Patients without myelographic
evidence of lumbar canal stenosis, who had been followed up for ≥ 1
year after the cervical surgery, served as controls (135 patients;
mean follow-up period 6.5 years (1 to 17)). Among the 39 patients
with asymptomatic lumbar canal stenosis, seven had lumbar-related
leg symptoms after the cervical surgery. Kaplan–Meier analysis showed that 89.6% (95% confidence interval
(CI) 75.3 to 96.0) and 76.7% (95% CI 53.7 to 90.3) of the patients
with asymptomatic lumbar canal stenosis were free from leg symptoms
for three and five years, respectively. There were no significant
differences between the study and control groups in the recovery
rate measured by the Japanese Orthopaedic Association score or improvement
in the Nurick score at one year after surgery or at the final follow-up. These results suggest that latent lumbar canal stenosis does
not influence recovery following surgery for cervical myelopathy;
moreover, prophylactic lumbar decompression does not appear to be
warranted as a routine procedure for coexistent asymptomatic lumbar
canal stenosis in patients with cervical myelopathy, when planning
cervical surgery.
The introduction of a trabecular tantalum rod
has been proposed for the management of early-stage osteonecrosis of
the femoral head but serves as a single-point of support of the
necrotic lesion. We describe a technique using two or three 4.2
mm (or later 4.7 mm) tantalum pegs for the prevention of collapse
of the necrotic lesion. We prospectively studied 21 patients (26
hips) with non-traumatic osteonecrosis of the femoral head treated
in this manner. Of these, 21 patients (24 hips) were available for
radiological and clinical evaluation at a mean follow-up of 46 months
(18 to 67). Radiological assessment showed that only eight hips
deteriorated according to the Association Research Circulation Osseous
classification, and four hips according to the Classification of
the Japanese Investigation Committee of Health and Welfare. Functional
improvement was obtained with an improvement in the mean Harris
hip score from 65.2 (33.67 to 95) to 88.1 (51.72 to 100), the mean
Merle D’Aubigné-Postel score from 13 (6 to 18) to 16 (11 to 18),
a mean visual analogue score for pain from 5.2 (0 to 9.5) to 2.6
(0 to 7), and the mean Short-Form 36 score from 80.4 (56.8 to 107.1)
to 92.4 (67.5 to 115.7). Of these 24 hips followed for a minimum
of 18 months, three were considered as failures at the final follow-up,
having required total hip replacement. One of the hips without full
follow-up was also considered to be a failure. In more than two-thirds
of the surviving hips a satisfactory clinical outcome was achieved
with promising radiological findings. The estimated mean implant
survival was 60 months (95% confidence interval 53.7 to 66.3).