To determine the effect of a change in design of a cementless
ceramic acetabular component in fixation and clinical outcome after
total hip arthroplasty We compared 342 hips (302 patients) operated between 1999 and
2005 with a relatively smooth hydroxyapatite coated acetabular component
(group 1), and 337 hips (310 patients) operated between 2006 and
2011 using a similar acetabular component with a macrotexture on
the entire outer surface of the component (group 2). The mean age of
the patients was 53.5 (14 to 70) in group 1 and 53.0 (15 to 70)
in group 2. The mean follow-up was 12.7 years (10 to 17) for group
1 and 7.2 years (4 to 10) for group 2.Aims
Patients and Methods
Slipped capital femoral epiphysis (SCFE) may
lead to symptomatic femoroacetabular impingement (FAI). We report our
experience of arthroscopic treatment, including osteochondroplasty,
for the sequelae of SCFE. Data were prospectively collected on patients undergoing arthroscopy
of the hip for the sequelae of SCFE between March 2007 and February
2013, including demographic data, radiological assessment of the
deformity and other factors that may influence outcome, such as
the presence of established avascular necrosis. Patients completed
the modified Harris hip score (mHHS) and the non-arthritic hip score
(NAHS) before and after surgery. In total, 18 patients with a mean age of 19 years (13 to 42),
were included in the study. All patients presented with pain in
the hip and mechanical symptoms, and had evidence of FAI (cam or
mixed impingement) on plain radiographs. The patients underwent arthroscopic osteoplasty of the femoral
neck. The mean follow-up was 29 months (23 to 56). The mean mHHS and NAHS scores improved from 56.2 (27.5 to 100.1)
and 52.1 (12.5 to 97.5) pre-operatively to 75.1 (33.8 to 96.8, p
= 0.01) and 73.6 (18.8 to 100, p = 0.02) at final follow-up, respectively.
Linear regression analysis demonstrated a significant association
between poorer outcome scores and increased time to surgery following SCFE
(p <
0.05 for all parameters except baseline MHHS). Symptomatic FAI following (SCFE) may be addressed using arthroscopic
techniques, and should be treated promptly to minimise progressive
functional impairment and chondrolabral degeneration. Take home message: Arthroscopy of the hip can be used to treat
femoroacetabular impingement successfully following SCFE. However,
this should be performed promptly after presentation in order to
prevent irreversible progression and poorer clinical outcomes. Cite this article:
We report the clinical and radiological outcome
of subcapital osteotomy of the femoral neck in the management of symptomatic
femoroacetabular impingement (FAI) resulting from a healed slipped
capital femoral epiphysis (SCFE). We believe this is only the second
such study in the literature. We studied eight patients (eight hips) with symptomatic FAI after
a moderate to severe healed SCFE. There were six male and two female
patients, with a mean age of 17.8 years (13 to 29). All patients underwent a subcapital intracapsular osteotomy of
the femoral neck after surgical hip dislocation and creation of
an extended retinacular soft-tissue flap. The mean follow-up was
41 months (20 to 84). Clinical assessment included measurement of
range of movement, Harris Hip Score (HHS) and Western Ontario and McMaster
Universities Osteoarthritis score (WOMAC). Radiological assessment
included pre- and post-operative calculation of the anterior slip
angle (ASA) and lateral slip angle (LSA), the anterior offset angle
(AOA) and centre head–trochanteric distance (CTD). The mean HHS
at final follow-up was 92.5 (85 to 100), and the mean WOMAC scores
for pain, stiffness and function were 1.3 (0 to 4), 1.4 (0 to 6)
and 3.6 (0 to 19) respectively. There was a statistically significant
improvement in all the radiological measurements post-operatively.
The mean ASA improved from 36.6° (29° to 44°) to 10.3° (5° to 17°)
(p <
0.01). The mean LSA improved from 36.6° (31° to 43°) to 15.4°
(8° to 21°) (p <
0.01). The mean AOA decreased from 64.4° (50°
to 78°) 32.0° (25° to 39°) post-operatively (p <
0.01). The mean
CTD improved from -8.2 mm (-13.8 to +3.1) to +2.8 mm (-7.6 to +11.0)
(p <
0.01). Two patients underwent further surgery for nonunion.
No patient suffered avascular necrosis of the femoral head. Subcapital osteotomy for patients with a healed SCFE is more
challenging than subcapital re-orientation in those with an acute
or sub-acute SCFE and an open physis. An effective correction of
the deformity, however, can be achieved with relief of symptoms
related to impingement. Cite this article:
The radiological evaluation of the anterolateral femoral head is an essential tool for the assessment of the cam type of femoroacetabular impingement. CT, MRI and frog lateral plain radiographs have all been suggested as imaging options for this type of lesion. The alpha angle is accepted as a reliable indicator of the cam type of impingement and may also be used as an assessment for the successful operative correction of the cam lesion. We studied the alpha angles of 32 consecutive patients with femoroacetabular impingement. The angle measured on frog lateral radiographs using templating tools was compared with that measured on CT scans in order to assess the reliability of the frog lateral view in analysing the alpha angle in cam impingement. A high interobserver reliability was noted for the assessment of the alpha angle on the frog lateral view with an intraclass correlation coefficient of 0.83. The mean alpha angle measured on the frog lateral view was 58.71° (32° to 83.3°) and that by CT was 65.11° (30° to 102°). A poor intraclass correlation coefficient (0.08) was noted between the measurements using the two systems. The frog lateral plain radiograph is not reliable for measuring the alpha angle. Various factors may be responsible for this such as the projection of the radiograph, the positioning of the patient and the quality of the image. CT may be necessary for accurate measurement of the alpha angle.
We report on gender-specific reference intervals
of the alpha angle and its association with other qualitative cam-type
findings in femoroacetabular impingement at the hip, according to
a population-based cohort of 2038 19-year-olds, 1186 of which were
women (58%). The alpha angle was measured on standardised frog-leg
lateral and anteroposterior (AP) views using digital measurement
software, and qualitative cam-type findings were assessed subjectively
on both views by independent observers. In all, 2005 participants
(837 men, 1168 women, mean age 18.6 years (17.2 to 20.1) were included
in the analysis. For the frog-leg view, the mean alpha angle (right
hip) was 47° (26 to 79) in men and 42° (29 to 76) in women, with
97.5 percentiles of 68° and 56°, respectively. For the AP view,
the mean values were 62° (40 to 105) and 52° (36 to 103) for men
and women, respectively, with 97.5 percentiles of 93° and 94°. Associations
between higher alpha angles and all qualitative cam-type findings
were seen for both genders on both views. The reference intervals
presented for the alpha angle in this cross-sectional study are
wide, especially for the AP view, with higher mean values for men
than women on both views. Cite this article:
