It is accepted that resurfacing hip replacement
preserves the bone mineral density (BMD) of the femur better than total
hip replacement (THR). However, no studies have investigated any
possible difference on the acetabular side. Between April 2007 and March 2009, 39 patients were randomised
into two groups to receive either a resurfacing or a THR and were
followed for two years. One patient’s resurfacing subsequently failed,
leaving 19 patients in each group. Resurfaced replacements maintained proximal femoral BMD and,
compared with THR, had an increased bone mineral density in Gruen
zones 2, 3, 6, and particularly zone 7, with a gain of 7.5% (95%
confidence interval (CI) 2.6 to 12.5) compared with a loss of 14.6%
(95% CI 7.6 to 21.6). Resurfacing replacements maintained the BMD
of the medial femoral neck and increased that in the lateral zones
between 12.8% (95% CI 4.3 to 21.4) and 25.9% (95% CI 7.1 to 44.6). On the acetabular side, BMD was similar in every zone at each
point in time. The mean BMD of all acetabular regions in the resurfaced
group was reduced to 96.2% (95% CI 93.7 to 98.6) and for the total
hip replacement group to 97.6% (95% CI 93.7 to 101.5) (p = 0.4863).
A mean total loss of 3.7% (95% CI 1.0 to 6.5) and 4.9% (95% CI 0.8
to 9.0) of BMD was found above the acetabular component in W1 and
10.2% (95% CI 0.9 to 19.4) and 9.1% (95% CI 3.8 to 14.4) medial
to the implant in W2 for resurfaced replacements and THRs respectively.
Resurfacing resulted in a mean loss of BMD of 6.7% (95% CI 0.7 to
12.7) in W3 but the BMD inferior to the acetabular component was
maintained in both groups. These results suggest that the ability of a resurfacing hip replacement
to preserve BMD only applies to the femoral side.
We undertook a cemental unipolar proximal femoral endoprosthetic replacement in 131 patients with a mean age of 50 years (2 to 84). Primary malignant tumours were present in 54 patients and 67 had metastatic disease. In addition, eight patients had either lymphoma or myeloma and two had non-oncological disorders. The mean follow-up was 27 months (0 to 180). An acetabular revision was required later in 14 patients, 12 of whom had been under the age of 21 years at the time of insertion of their original prosthesis. The risk of acetabular revision in patients over 21 years of age was 8% at five years compared with 36% in those aged under 21 years. All the unipolar hips in this younger age group required revision within 11 years of the initial operation. We conclude that unipolar replacement should not be used in younger patients and should be avoided in patients with a life expectancy of more than five years.
Many tumors metastasise to bone, therefore, pathologic
fracture and impending pathologic fractures are common reasons for
orthopedic consultation. Having effective treatment strategies is
important to avoid complications, and relieve pain and preserve
function. Thorough pre-operative evaluation is recommended for medical
optimization and to ensure that the lesion is in fact a metastasis
and not a primary bone malignancy. For impending fractures, various scoring
systems have been proposed to determine the risk of fracture, and
therefore the need for prophylactic stabilisation. Lower score lesions
can often be treated with radiation, while more problematic lesions
may require internal fixation. Intramedullary fixation is generally
preferred due to favorable biomechanics. Arthroplasty may be required
for lesions with massive bony destruction where internal fixation
attempts are likely to fail. Radiation may also be useful postoperatively
to minimise construct failure due to tumor progression.
Revision after failed femoral components may
be technically demanding due to loss of peri-prosthetic bone. This retrospective
study evaluated the long-term results of femoral revision using
the cementless Wagner Self-Locking stem. Between 1992 and 1998,
68 consecutive hips in 66 patients underwent femoral revision using
this implant. A total of 25 patients died from unrelated causes
without further revision; the remaining 41 hips in 41 patients (12 men
and 29 women) with a mean age of 61 years (29 to 80) were reviewed
at a mean follow-up of 13.9 years (10.4 to 15.8). A transfemoral
approach was used in 32 hips. A total of five stems required further
revision because of infection in two, progressive subsidence in
two and recurrent dislocation in one. Four hips had dislocated and
eight stems had subsided ≥ 10 mm. The mean Harris hip score improved
from 33 points pre-operatively to 75 points at final follow-up (p
<
0.001). In all, 33 stems (91.7%) showed radiological signs
of stable bone fixation. The cumulative survival rates at 15.8 years
with femoral revision for any reason and for stem failure as the
endpoints were 92.0% (95% confidence interval (CI) 86.0% to 98.4%)
and 96.6% (95% CI 92.2% to 100%), respectively. The survivorship
with revision and ≥ 10 mm migration of the stem as the endpoint
was 83.6% (95% CI 76.6% to 91.4%). This study shows quite good survival and moderate clinical outcome
when using a monoblock tapered titanium stem for supporting the
regeneration of bone in complex revision hip surgery.
We determined the midterm survival, incidence
of peri-prosthetic fracture and the enhancement of the width of
the femur when combining struts and impacted bone allografts in
24 patients (25 hips) with severe femoral bone loss who underwent
revision hip surgery. The pre-operative diagnosis was aseptic loosening
in 16 hips, second-stage reconstruction in seven, peri-prosthetic
fracture in one and stem fracture in one hip. A total of 14 hips
presented with an Endoklinik grade 4 defect and 11 hips a grade
3 defect. The mean pre-operative Merle D’Aubigné and Postel score
was 5.5 points (1 to 8). The survivorship was 96% (95% confidence interval 72 to 98) at
a mean of 54.5 months (36 to 109). The mean functional score was
17.3 points (16 to 18). One patient in which the strut did not completely
bypass the femoral defect was further revised using a long cemented
stem due to peri-prosthetic fracture at six months post-operatively.
The mean subsidence of the stem was 1.6 mm (1 to 3). There was no
evidence of osteolysis, resorption or radiolucencies during follow-up
in any hip. Femoral width was enhanced by a mean of 41% (19% to
82%). A total of 24 hips had partial or complete bridging of the
strut allografts. This combined biological method was associated with a favourable
survivorship, a low incidence of peri-prosthetic fracture and enhancement
of the width of the femur in revision total hip replacement in patients
with severe proximal femoral bone loss.
Femoroacetabular impingement causes groin pain
and decreased athletic performance in active adults. This bony conflict
may result in femoroacetabular subluxation if of sufficient magnitude. The ligamentum teres has recently been reported to be capable
of withstanding tensile loads similar to that of the anterior cruciate
ligament, and patents with early subluxation of the hip may become
dependent on the secondary restraint that is potentially provided
by the ligamentum teres. Rupture of the ligamentum may thus cause
symptomatic hip instability during athletic activities. An arthroscopic reconstruction of the ligamentum teres using
iliotibial band autograft was performed in an attempt to restore
this static stabiliser in a series of four such patients. Early
clinical results have been promising. The indications, technique
and early outcomes of this procedure are discussed.
The pre-operative differentiation between enchondroma,
low-grade chondrosarcoma and high-grade chondrosarcoma remains a
diagnostic challenge. We reviewed the accuracy and safety of the
radiological grading of cartilaginous tumours through the assessment
of, first, pre-operative radiological and post-operative histological agreement,
and second the rate of recurrence in lesions confirmed as high-grade
on histology. We performed a retrospective review of major long
bone cartilaginous tumours managed by curettage as low grade between
2001 and 2012. A total of 53 patients with a mean age of 47.6 years
(8 to 71) were included. There were 23 men and 30 women. The tumours
involved the femur (n = 20), humerus (n = 18), tibia (n = 9), fibula
(n = 3), radius (n = 2) and ulna (n = 1). Pre-operative diagnoses
resulted from multidisciplinary consensus following radiological
review alone for 35 tumours, or with the addition of pre-operative
image guided needle biopsy for 18. The histologically confirmed diagnosis
was enchondroma for two (3.7%), low-grade chondrosarcoma for 49
(92.6%) and high-grade chondrosarcoma for two (3.7%). Three patients
with a low-grade tumour developed a local recurrence at a mean of 15
months (12 to 17) post-operatively. A single high-grade recurrence
(grade II) was treated with tibial diaphyseal replacement. The overall
recurrence rate was 7.5% at a mean follow-up of 4.7 years (1.2 to
12.3). Cartilaginous tumours identified as low-grade on pre-operative
imaging with or without additional image-guided needle biopsy can
safely be managed as low-grade without pre-operative histological
diagnosis. A few tumours may demonstrate high-grade features histologically,
but the rates of recurrence are not affected. Cite this article:
In 2005, we demonstrated that the polished triple-tapered
C-stem at two years had migrated distally and rotated internally.
From that series, 33 patients have now been followed radiologically,
clinically and by radiostereometric analysis (RSA) for up to ten
years. The distal migration within the cement mantle had continued
and reached a mean of 2 mm (0.5 to 4.0) at ten years. Internal rotation,
also within the cement mantle, was a mean 3.8° (external 1.6° to
internal 6.6°) The cement mantle did not show any sign of migration
or loosening in relation to the femoral bone. There were no clinical
or radiological signs indicating that the migration or rotation
within the cement mantle had had any adverse effects for the patients. Cite this article:
Metal-on-metal hip resurfacing (MOMHR) is available as an alternative
option for younger, more active patients. There are failure modes
that are unique to MOMHR, which include loosening of the femoral
head and fractures of the femoral neck. Previous studies have speculated
that changes in the vascularity of the femoral head may contribute
to these failure modes. This study compares the survivorship between
the standard posterior approach (SPA) and modified posterior approach
(MPA) in MOMHR. A retrospective clinical outcomes study was performed examining
351 hips (279 male, 72 female) replaced with Birmingham Hip Resurfacing
(BHR, Smith and Nephew, Memphis, Tennessee) in 313 patients with
a pre-operative diagnosis of osteoarthritis. The mean follow-up
period for the SPA group was 2.8 years (0.1 to 6.1) and for the
MPA, 2.2 years (0.03 to 5.2); this difference in follow-up period
was statistically significant (p <
0.01). Survival analysis was
completed using the Kaplan–Meier method. Objectives
Methods
Iontophoresis is a novel technique which may be used to facilitate the movement of antibiotics into the substance of bone using an electrical potential applied externally. We have examined the rate of early infection in allografts following application of this technique in clinical practice. A total of 31 patients undergoing revision arthroplasty or surgery for limb salvage received 34 iontophoresed sequential allografts, of which 26 survived for a minimum of two years. The mean serum antibiotic levels after operation were low (gentamicin 0.37 mg/l (0.2 to 0.5); flucloxacillin 1 mg/l (0 to 1) and the levels in the drains were high (gentamicin 40 mg/l (2.5 to 131); flucloxacillin 17 mg/l (1 to 43). There were no early deep infections. Two late infections were presumed to be haemotogenous; 28 of the 34 allografts were retained. In 12 patients with pre-existing proven infection further infection has not occurred at a mean follow-up of 51 months (24 to 82).
Internal lengthening devices in the femur lengthen
along the anatomical axis, potentially creating lateral shift of
the mechanical axis. We aimed to determine whether femoral lengthening
along the anatomical axis has an inadvertent effect on lower limb
alignment. Isolated femoral lengthening using the Intramedullary
Skeletal Kinetic Distractor was performed in 27 femora in 24 patients
(mean age 32 years (16 to 57)). Patients who underwent simultaneous realignment
procedures or concurrent tibial lengthening, or who developed mal-
or nonunion, were excluded. Pre-operative and six-month post-operative
radiographs were used to measure lower limb alignment. The mean lengthening
achieved was 4.4 cm (1.5 to 8.0). In 26 of 27 limbs, the mechanical
axis shifted laterally by a mean of 1.0 mm/cm of lengthening (0
to 3.5). In one femur that was initially in varus, a 3 mm medial
shift occurred during a lengthening of 2.2 cm. In a normally aligned limb, intramedullary lengthening along
the anatomical axis of the femur results in a lateral shift of the
mechanical axis by approximately 1 mm for each 1 cm of lengthening.
Eighteen hip fusions were converted to total
hip replacements. A constrained acetabular liner was used in three hips.
Mean follow up was five years (two to 15). Two (11%) hips failed,
requiring revision surgery and two patients (11%) had injury to
the peroneal nerve. Heterotopic ossification developed in seven
(39%) hips, in one case resulting in joint ankylosis. No hips dislocated. Conversion of hip fusion to hip replacement carries an increased
risk of heterotopic ossification and neurological injury. We advise
prophylaxis against heterotropic ossification. When there is concern
about hip stability we suggest that the use of a constrained acetabular
liner is considered. Despite the potential for complications, this procedure
had a high success rate and was effective in restoring hip function.
Conventional methods of treating ankle fractures
in the elderly are associated with high rates of complication. We describe
the results of treating these injuries in 48 frail elderly patients
with a long calcaneotalotibial nail. The mean age of the group was 82 years (61 to 96) and 41 (85%)
were women. All were frail, with multiple medical comorbidities
and their mean American Society of Anaesthesiologists score was
3 (3 to 4). None could walk independently before their operation.
All the fractures were displaced and unstable; the majority (94%,
45 of 48) were low-energy injuries and 40% (19 of 48) were open. The overall mortality at six months was 35%. Of the surviving
patients, 90% returned to their pre-injury level of function. The
mean pre- and post-operative Olerud and Molander questionnaire scores
were 62 and 57 respectively. Complications included superficial
infection (4%, two of 48); deep infection (2%, one of 48); a broken
or loose distal locking screw (6%, three of 48); valgus malunion
(4%, two of 48); and one below-knee amputation following an unsuccessful
vascular operation. There were no cases of nonunion, nail breakage
or peri-prosthetic fracture. A calcaneotalotibial nail is an excellent device for treating
an unstable fracture of the ankle in the frail elderly patient.
It allows the patient to mobilise immediately and minimises the
risk of bone or wound problems. A long nail which crosses the isthmus
of the tibia avoids the risk of peri-prosthetic fracture associated
with shorter devices. Cite this article:
The lack of a consensus for core health outcomes
that should be reported in clinical research has hampered study design
and evidence synthesis. We report a United Kingdom consensus for
a core outcome set (COS) for clinical trials of patients with a
hip fracture. We adopted a modified nominal group technique to derive consensus
on 1) which outcome domains should be measured, and 2) methods of
assessment. Participants reflected a diversity of perspectives and
experience. They received an evidence synthesis and postal questionnaire
in advance of the consensus meeting, and ranked the importance of
candidate domains and the relevance and suitability of short-listed
measures. During the meeting, pre-meeting source data and questionnaire
responses were summarised, followed by facilitated discussion and
a final plenary session. A COS was determined using a closed voting
system: a 70% consensus was required. Consensus supported a five-domain COS: mortality, pain, activities
of daily living, mobility, and health-related quality of life (HRQL).
Single-item measures of mortality and mobility (indoor/outdoor walking
status) and a generic multi-item measure of HRQL - the EuroQoL EQ-5D
- were recommended. These measures should be included as a minimum
in all hip fracture trials. Other outcome measures should be added
depending on the particular interventions being studied. Cite this article:
Total hip replacement for high dislocation of the hip joint remains technically difficult in terms of preparation of the true acetabulum and restoration of leg length. We describe our experience of cementless total hip replacement combined with a subtrochanteric femoral shortening osteotomy in 20 hips with Crowe grade IV dislocation with a mean follow-up of 8.1 years (4 to 11.5). There was one man and 17 women with a mean age of 55 years (44 to 69) at the time of the operation. After placment of the acetabular component at the site of the natural acetabulum, a cementless porous-coated cylindrical femoral component was implanted following a subtrochanteric femoral shortening osteotomy. The mean Japanese Orthopedic Association hip score improved from a mean of 38 (22 to 62) to a mean of 83 points (55 to 98) at the final follow-up. The mean lengthening of the leg was 14.8 mm (−9 to 34) in patients with iliofemoral osteoarthritis and 35.3 mm (15 to 51) in patients with no arthritic changes. No nerve palsy was observed. Total hip replacement combined with subtrochanteric shortening femoral osteotomy in this situation is beneficial in avoiding nerve injury and still permits valuable improvement in inequality of leg length.
The June 2012 Oncology Roundup360 looks at: avoiding pelvic hemipelvectomy; proximal femoral metastasis; extendible prostheses; rotationplasty; soft-tissue sarcomas; osteosarcoma of the pelvis; recurrent chondrosarcoma ; MRI and the differentiation between benign and malignant lesions; and malignant fibrous histiocytoma.
In Japan, osteoarthritis (OA) of the hip secondary
to acetabular dysplasia is very common, and there are few data concerning
the pathogeneses and incidence of femoroacetabular impingement (FAI).
We have attempted to clarify the radiological prevalence of painful
FAI in a cohort of Japanese patients and to investigate the radiological findings.
We identified 176 symptomatic patients (202 hips) with Tönnis grade
0 or 1 osteoarthritis, whom we prospectively studied between August
2011 and July 2012. There were 61 men (65 hips) and 115 women (137
hips) with a mean age of 51.8 years (11 to 83). Radiological analyses
included the α-angle, centre–edge angle, cross-over sign, pistol
grip deformity and femoral head neck ratio. Of the 202 hips, 79
(39.1%) had acetabular dysplasia, while 80 hips (39.6%) had no known
aetiology. We found evidence of FAI in 60 hips (29.7%). Radiological
FAI findings associated with cam deformity were the most common.
There was a significant relationship between the pistol grip deformity
and both the α-angle (p <
0.001) and femoral head–neck ratio
(p = 0.024). Radiological evidence of symptomatic FAI was not uncommon
in these Japanese patients. Cite this article:
If a surgeon is faced with altered lesser trochanter
anatomy when revising the femoral component in revision total hip
replacement, a peri-prosthetic fracture, or Paprosky type IIIb or
type IV femoral bone loss, a modular tapered stem offers the advantages
of accurately controlling femoral version and length. The splines
of the taper allow rotational control, and improve the fit in femoral
canals with diaphyseal bone loss. In general, two centimetres of diaphyseal
contact is all that is needed to gain stability with modular tapered
stems. By allowing the proximal body trial to rotate on a well-fixed
distal segment during trial reduction, appropriate anteversion can
be obtained in order to improve intra-operative stability, and decrease
the dislocation risk. However, modular stems should not be used for
all femoral revisions, as implant fracture and corrosion at modular
junctions can still occur. Cite this article:
The purpose of this prospective study was to
evaluate the long-term clinical and radiological outcomes of revision of
the femoral component of a total hip replacement using impaction
bone grafting. Femoral revision with an impacted allograft was performed
on 29 patients (31 hips). In all, 21 hips (68%) had grade III or
IV femoral defects according to the Endo-Klinik classification.
A total of 11 patients (12 hips) died before the ten-year follow-up
period. Of the remaining patients, 18 patients (19 hips) were followed
for 10 to 15 years; three further patients died during this time.
None of the 31 stems underwent further revision of their stem. However,
four stems showed extensive subsidence (>
15 mm). One of these patients
had a femoral fracture that required fixation. Three other patients
had a femoral fracture, two of which required fixation and the other
was treated conservatively. Patients with a femoral fracture and/or
severe subsidence had significantly more grade IV defects (six of
seven hips; p = 0.004). One patient needed a closed reduction for
dislocation. Impaction allografting in revision hip surgery gives good long-term
results for femora with grades I, II and III Endo-Klinik-classified
defects. Extensive subsidence and femoral fractures were seen mainly
in patients with grade IV damaged femora.
Cementless femoral stems are currently preferred
for total hip replacement (THR) in the United States. Improvements
in stem design, instrumentation and surgical technique have made
this technology highly successful, reproducible, and applicable
to the vast majority of patients requiring a THR. However, there
are ongoing developments in some aspects of stem design that influence
clinical results, the incidence of complications and their inherent adaptability
in accommodating the needs of individual patients. Here we examine
some of these design features. Cite this article: