In Norway total joint replacement after hip dysplasia
is reported more commonly than in neighbouring countries, implying
a higher prevalence of the condition. We report on the prevalence
of radiological features associated with hip dysplasia in a population
of
2081 19-year-old Norwegians. The radiological measurements used
to define hip dysplasia were Wiberg’s centre-edge (CE) angle at
thresholds of <
20° and <
25°, femoral head extrusion index
<
75%, Sharp’s angle >
45°, an acetabular depth to width ratio
<
250 and the sourcil shape assessed subjectively. The whole
cohort underwent clinical examination of their range of hip movement,
body mass index (BMI), and Beighton hypermobility score, and were
asked to complete the EuroQol (EQ-5D) and Western Ontario and McMaster
Universities Osteoarthritis Index (WOMAC). The prevalence of hip
dysplasia in the cohort varied from 1.7% to 20% depending on the
radiological marker used. A Wiberg’s CE angle <
20° was seen
in 3.3% of the cohort: 4.3% in women and 2.4% in men. We found no
association between subjects with multiple radiological signs indicative
of dysplasia and BMI, Beighton score, EQ-5D or WOMAC. Although there
appears to be a high prevalence of hip dysplasia among 19-year-old
Norwegians, this is dependent on the radiological parameters applied. Cite this article:
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.
It has been noted that bony union of a pars defect can be achieved in children if they wear a trunk brace. Our aim was to evaluate how the stage of the defect on CT and the presence or absence of high signal change in the adjacent pedicle on T2-weighted MRI were related to bony healing. We treated 23 children conservatively for at least three months. There were 19 boys and four girls with a mean age of 13.5 years (7 to 17). They were asked to refrain from sporting activity and to wear a Damen soft thoracolumbosacral type brace. There were 41 pars defects in 23 patients. These were classified as an early, progressive or terminal stage on CT. The early-stage lesions had a hairline crack in the pars interarticularis, which became a gap in the progressive stage. A terminal-stage defect was equivalent to a pseudarthrosis. On the T2-weighted MR scan the presence or absence of high signal change in the adjacent pedicle was assessed and on this basis the defects were divided into high signal change-positive or -negative. Healing of the defect was assessed by CT. In all, 13 (87%) of the 15 early defects healed. Of 19 progressive defects, only six (32%) healed. None of the seven terminal defects healed. Of the 26 high signal change-positive defects 20 (77%) healed after conservative treatment whereas none of the high signal change-negative defects did so. We concluded that an early-stage defect on CT and high signal change in the adjacent pedicle on a T2-weighted MR scan are useful predictors of bony healing of a pars defect in children after conservative treatment.