When performing revision total hip arthroplasty using diaphyseal-engaging titanium tapered stems (TTS), the recommended 3 to 4 cm of stem-cortical diaphyseal contact may not be available. In challenging cases such as these with only 2 cm of contact, can sufficient axial stability be achieved and what is the benefit of a prophylactic cable? This study sought to determine, first, whether a prophylactic cable allows for sufficient axial stability when the contact length is 2 cm, and second, if differing TTS taper angles (2° vs 3.5°) impact these results. A biomechanical matched-pair cadaveric study was designed using six matched pairs of human fresh cadaveric femora prepared so that 2 cm of diaphyseal bone engaged with 2° (right femora) or 3.5° (left femora) TTS. Before impaction, three matched pairs received a single 100 lb-tensioned prophylactic beaded cable; the remaining three matched pairs received no cable adjuncts. Specimens underwent stepwise axial loading to 2600 N or until failure, defined as stem subsidence > 5 mm.Aims
Methods
Revision total hip arthroplasty in patients with Vancouver type B3 fractures with Paprosky type IIIA, IIIB, and IV femoral defects are difficult to treat. One option for Paprovsky type IIIB and IV defects involves modular cementless, tapered, revision femoral components in conjunction with distal interlocking screws. The aim of this study was to analyze the rate of reoperations and complications and union of the fracture, subsidence of the stem, mortality, and the clinical outcomes in these patients. A total of 46 femoral components in patients with Vancouver B3 fractures (23 with Paprosky type IIIA, 19 with type IIIB, and four with type IV defects) in 46 patients were revised with a transfemoral approach using a modular, tapered, cementless revision Revitan curved femoral component with distal cone-in-cone fixation and prospectively followed for a mean of 48.8 months (SD 23.9; 24 to 112). The mean age of the patients was 80.4 years (66 to 100). Additional distal interlocking was also used in 23 fractures in which distal cone-in-cone fixation in the isthmus was < 3 cm.Aims
Methods
Although the Fitmore Hip Stem has been on the market for almost 15 years, it is still not well documented in randomized controlled trials. This study compares the Fitmore stem with the CementLeSs (CLS) in several different clinical and radiological aspects. The hypothesis is that there will be no difference in outcome between stems. In total, 44 patients with bilateral hip osteoarthritis were recruited from the outpatient clinic at a single tertiary orthopaedic centre. The patients were operated with bilateral one-stage total hip arthroplasty. The most painful hip was randomized to either Fitmore or CLS femoral component; the second hip was operated with the femoral component not used on the first side. Patients were evaluated at three and six months and at one, two, and five years postoperatively with patient-reported outcome measures, radiostereometric analysis, dual-energy X-ray absorptiometry, and conventional radiography. A total of 39 patients attended the follow-up visit at two years (primary outcome) and 35 patients at five years. The primary outcome was which hip the patient considered to have the best function at two years.Aims
Methods
Eccentric reductions may become concentric through femoral head ‘docking’ (FHD) following closed reduction (CR) for developmental dysplasia of the hip (DDH). However, changes regarding position and morphology through FHD are not well understood. We aimed to assess these changes using serial MRI. We reviewed 103 patients with DDH successfully treated by CR and spica casting in a single institution between January 2016 and December 2020. MRI was routinely performed immediately after CR and at the end of each cast. Using MRI, we described the labrum-acetabular cartilage complex (LACC) morphology, and measured the femoral head to triradiate cartilage distance (FTD) on the midcoronal section. A total of 13 hips with initial complete reduction (i.e. FTD < 1 mm) and ten hips with incomplete MRI follow-up were excluded. A total of 86 patients (92 hips) with a FTD > 1 mm were included in the analysis.Aims
Methods
This study aimed to determine whether lateral femoral wall thickness (LWT) < 20.5 mm was associated with increased revision risk of intertrochanteric fracture (ITF) of the hip following sliding hip screw (SHS) fixation when the medial calcar was intact. Additionally, the study assessed the association between LWT and patient mortality. This retrospective study included ITF patients aged 50 years and over treated with SHS fixation between 2019 and 2021 at a major trauma centre. Demographic information, fracture type, delirium status, American Society of Anesthesiologists grade, and length of stay were collected. LWT and tip apex distance were measured. Revision surgery and mortality were recorded at a mean follow-up of 19.5 months (1.6 to 48). Cox regression was performed to evaluate independent risk factors associated with revision surgery and mortality.Aims
Methods
The aim of this study was to examine the implant accuracy of custom-made partial pelvis replacements (PPRs) in revision total hip arthroplasty (rTHA). Custom-made implants offer an option to achieve a reconstruction in cases with severe acetabular bone loss. By analyzing implant deviation in CT and radiograph imaging and correlating early clinical complications, we aimed to optimize the usage of custom-made implants. A consecutive series of 45 (2014 to 2019) PPRs for Paprosky III defects at rTHA were analyzed comparing the preoperative planning CT scans used to manufacture the implants with postoperative CT scans and radiographs. The anteversion (AV), inclination (IC), deviation from the preoperatively planned implant position, and deviation of the centre of rotation (COR) were explored. Early postoperative complications were recorded, and factors for malpositioning were sought. The mean follow-up was 30 months (SD 19; 6 to 74), with four patients lost to follow-up.Aims
Methods
Periprosthetic hip fractures (PPFs) after total hip arthroplasty are difficult to treat. Therefore, it is important to identify modifiable risk factors such as stem selection to reduce the occurrence of PPFs. This study aimed to clarify differences in fracture torque, surface strain, and fracture type analysis between three different types of cemented stems. We conducted biomechanical testing of bone analogues using six cemented stems of three different types: collarless polished tapered (CPT) stem, Versys Advocate (Versys) stem, and Charnley-Marcel-Kerboull (CMK) stem. Experienced surgeons implanted each of these types of stems into six bone analogues, and the analogues were compressed and internally rotated until failure. Torque to fracture and fracture type were recorded. We also measured surface strain distribution using triaxial rosettes.Aims
Methods
Hip arthroplasty aims to accurately recreate joint biomechanics. Considerable attention has been paid to vertical and horizontal offset, but femoral head centre in the anteroposterior (AP) plane has received little attention. This study investigates the accuracy of restoration of joint centre of rotation in the AP plane. Postoperative CT scans of 40 patients who underwent unilateral uncemented total hip arthroplasty were analyzed. Anteroposterior offset (APO) and femoral anteversion were measured on both the operated and non-operated sides. Sagittal tilt of the femoral stem was also measured. APO measured on axial slices was defined as the perpendicular distance between a line drawn from the anterior most point of the proximal femur (anterior reference line) to the centre of the femoral head. The anterior reference line was made parallel to the posterior condylar axis of the knee to correct for rotation.Aims
Methods
This study aimed to evaluate the accuracy of implant placement with robotic-arm assisted total hip arthroplasty (THA) in patients with developmental dysplasia of the hip (DDH). The study analyzed a consecutive series of 69 patients who underwent robotic-arm assisted THA between September 2018 and December 2019. Of these, 30 patients had DDH and were classified according to the Crowe type. Acetabular component alignment and 3D positions were measured using pre- and postoperative CT data. The absolute differences of cup alignment and 3D position were compared between DDH and non-DDH patients. Moreover, these differences were analyzed in relation to the severity of DDH. The discrepancy of leg length and combined offset compared with contralateral hip were measured.Aims
Methods
Various surgical techniques have been described for total hip arthroplasty (THA) in patients with Crowe type III dislocated hips, who have a large acetabular bone defect. The aim of this study was to evaluate the long-term clinical results of patients in whom anatomical reconstruction of the acetabulum was performed using a cemented acetabular component and autologous bone graft from the femoral neck. A total of 22 patients with Crowe type III dislocated hips underwent 28 THAs using bone graft from the femoral neck between 1979 and 2000. A Charnley cemented acetabular component was placed at the level of the true acetabulum after preparation with bone grafting. All patients were female with a mean age at the time of surgery of 54 years (35 to 68). A total of 18 patients (21 THAs) were followed for a mean of 27.2 years (20 to 33) after the operation.Aims
Methods
Surgical treatment of hip fracture is challenging; the bone is porotic and fixation failure can be catastrophic. Novel implants are available which may yield superior clinical outcomes. This study compared the clinical effectiveness of the novel X-Bolt Hip System (XHS) with the sliding hip screw (SHS) for the treatment of fragility hip fractures. We conducted a multicentre, superiority, randomized controlled trial. Patients aged 60 years and older with a trochanteric hip fracture were recruited in ten acute UK NHS hospitals. Participants were randomly allocated to fixation of their fracture with XHS or SHS. A total of 1,128 participants were randomized with 564 participants allocated to each group. Participants and outcome assessors were blind to treatment allocation. The primary outcome was the EuroQol five-dimension five-level health status (EQ-5D-5L) utility at four months. The minimum clinically important difference in utility was pre-specified at 0.075. Secondary outcomes were EQ-5D-5L utility at 12 months, mortality, residential status, mobility, revision surgery, and radiological measures.Aims
Methods
Fixation of osteoporotic proximal humerus fractures remains challenging even with state-of-the-art locking plates. Despite the demonstrated biomechanical benefit of screw tip augmentation with bone cement, the clinical findings have remained unclear, potentially as the optimal augmentation combinations are unknown. The aim of this study was to systematically evaluate the biomechanical benefits of the augmentation options in a humeral locking plate using finite element analysis (FEA). A total of 64 cement augmentation configurations were analyzed using six screws of a locking plate to virtually fix unstable three-part fractures in 24 low-density proximal humerus models under three physiological loading cases (4,608 simulations). The biomechanical benefit of augmentation was evaluated through an established FEA methodology using the average peri-screw bone strain as a validated predictor of cyclic cut-out failure.Aims
Methods
The direct anterior (DA) approach has been associated with rapid patient recovery after total hip arthroplasty (THA) but may be associated with more frequent femoral complications including implant loosening. The objective of this study was to determine whether the addition of a collar to the femoral stem affects implant migration, patient activity, and patient function following primary THA using the DA approach. Patients were randomized to either a collared (n = 23) or collarless (n = 26) cementless femoral stem implanted using the DA approach. Canal fill ratio (CFR) was measured on the first postoperative radiographs. Patients underwent a supine radiostereometric analysis (RSA) exam postoperatively on the day of surgery and at two, four, six, 12, 26, and 52 weeks postoperatively. Patient-reported outcome measures (Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index, the 12-item Short Form Health Survey Mental and Physical Score, and University of California, Los Angeles (UCLA) Activity Score) were measured preoperatively and at each post-surgery clinic visit. Activity and function were also measured as the weekly average step count recorded by an activity tracker, and an instrumented timed up-and-go (TUG) test in clinic, respectively.Aims
Methods
The aim of this study was to investigate whether the use of antibiotic-loaded bone cement influenced the risk of revision surgery after primary total hip arthroplasty (THA) for osteoarthritis. The study involved data collected by the National Joint Registry (NJR) for England and Wales, Northern Ireland and the Isle of Man between 1 September 2005 and 31 August 2017. Cox proportional hazards were used to investigate the association between use of antibiotic-loaded bone cement and the risk of revision due to prosthetic joint infection (PJI), with adjustments made for the year of the initial procedure, age at the time of surgery, sex, American Society of Anesthesiologists (ASA) grade, head size, and body mass index (BMI). We looked also at the association between use of antibiotic-loaded bone cement and the risk of revision due to aseptic loosening or osteolysis.Aims
Methods
The complete removal of the cement mantle at revision arthroplasty can be extremely difficult. Some authors advise a ‘cement-within-cement’ revision technique in which a new layer of cement is applied to the old before insertion of the femoral component. We could find no long-term clinical data regarding the success of this procedure. In a simple
Short, bone-conserving femoral components are increasingly used in total hip arthroplasty (THA). They are expected to allow tissue-conserving implantation and to render future revision surgery more straightforward but the long-term data on such components is limited. One such component is the global tissue-sparing (GTS) stem. Following the model for stepwise introduction of new orthopaedic implants, we evaluated early implant fixation and clinical outcome of this novel short-stem THA and compared it to that of a component with established good long-term clinical outcome. In total, 50 consecutive patients ≤ 70 years old with end-stage symptomatic osteo-arthritis were randomized to receive THA with the GTS stem or the conventional Taperloc stem using the anterior supine intermuscular approach by two experienced hip surgeons in two hospitals in the Netherlands. Primary outcome was implant migration. Patients were followed using routine clinical examination, patient reported outcome using Harris Hip Score (HHS), Hip Disability And Osteoarthritis Outcome Score (HOOS), EuroQol five-dimension questionnaire (EQ5D), and Roentgen Stereophotogrammetric Analysis (RSA) at three, six, 12, and 24 months. This study evaluated the two-year follow-up results.Aims
Methods
Vancouver type B periprosthetic femoral fractures (PFF) are challenging complications after total hip arthroplasty (THA), and some treatment controversies remain. The objectives of this study were: to evaluate the short-to-mid-term clinical outcomes after treatment of Vancouver type B PFF and to compare postoperative outcome in subgroups according to classifications and treatments; to report the clinical outcomes after conservative treatment; and to identify risk factors for postoperative complications in Vancouver type B PFF. A total of 97 consecutive PPFs (49 males and 48 females) were included with a mean age of 66 years (standard deviation (SD) 14.9). Of these, 86 patients were treated with surgery and 11 were treated conservatively. All living patients had a minimum two-year follow-up. Patient demographics details, fracture healing, functional scores, and complications were assessed. Clinical outcomes between internal fixation and revisions in patients with or without a stable femoral component were compared. Conservatively treated PPFs were evaluated in terms of mortality and healing status. A logistic regression analysis was performed to identify risk factors for complications.Aims
Methods
The paradoxical migration of the femoral neck element (FNE) superomedially against gravity, with respect to the intramedullary component of the cephalomedullary device, is a poorly understood phenomenon increasingly seen in the management of pertrochanteric hip fractures with the intramedullary nail. The aim of this study was to investigate the role of bidirectional loading on the medial migration phenomenon, based on unique wear patterns seen on scanning electron microscopy of retrieved implants suggestive of FNE toggling. A total of 18 synthetic femurs (Sawbones, Vashon Island, Washington) with comminuted pertrochanteric fractures were divided into three groups (n = 6 per group). Fracture fixation was performed using the Proximal Femoral Nail Antirotation (PFNA) implant (Synthes, Oberdorf, Switzerland; n = 6). Group 1 was subjected to unidirectional compression loading (600 N), with an elastomer (70A durometer) replacing loose fracture fragments to simulate surrounding soft-tissue tensioning. Group 2 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading), also with the elastomer replacing loose fracture fragments. Group 3 was subjected to bidirectional loading (600 N compression loading, 120 N tensile loading) without the elastomer. All constructs were tested at 2 Hz for 5000 cycles or until cut-out occurred. The medial migration distance (MMD) was recorded at the end of the testing cycles.Objectives
Methods
We investigated patient characteristics and outcomes of Vancouver type B periprosthetic fractures treated with femoral component revision and/or osteosynthesis. The study utilized data from the Swedish Hip Arthroplasty Register (SHAR) and information from patient records. We included all primary total hip arthroplasties (THAs) performed in Sweden since 1979, and undergoing further surgery due to Vancouver type B periprosthetic femoral fracture between 2001 and 2011. The primary outcome measure was any further reoperation between 2001 and 2013. Cross-referencing with the National Patient Register was performed in two stages, in order to identify all surgical procedures not recorded on the SHAR.Aims
Patients and Methods
The aim of this study was to assess the functional gain achieved following hip resurfacing arthroplasty (HRA). A total of 28 patients (23 male, five female; mean age, 56 years (25 to 73)) awaiting Birmingham HRA volunteered for this prospective gait study, with an age-matched control group of 26 healthy adults (16 male, ten female; mean age, 56 years (33 to 84)). The Oxford Hip Score (OHS) and gait analysis using an instrumented treadmill were used preoperatively and more than two years postoperatively to measure the functional change attributable to the intervention.Aims
Patients and Methods
Aims
Patients and Methods
Accurate placement of the acetabular component is essential in
total hip arthroplasty (THA). The purpose of this study was to determine
if the ability to achieve inclination of the acetabular component
within the ‘safe-zone’ of 30° to 50° could be improved with the
use of an inclinometer. We reviewed 167 primary THAs performed by a single surgeon over
a period of 14 months. Procedures were performed at two institutions:
an inpatient hospital, where an inclinometer was used (inclinometer
group); and an ambulatory centre, where an inclinometer was not
used as it could not be adequately sterilized (control group). We excluded
47 patients with a body mass index (BMI) of > 40 kg/m2,
age of > 68 years, or a surgical indication other than osteoarthritis
whose treatment could not be undertaken in the ambulatory centre.
There were thus 120 patients in the study, 68 in the inclinometer
group and 52 in the control group. The inclination angles of the acetabular
component were measured from de-identified plain radiographs by
two blinded investigators who were not involved in the surgery.
The effect of the use of the inclinometer on the inclination angle
was determined using multivariate regression analysis.Aims
Patients and Methods
It is important to consider sagittal pelvic rotation when introducing
the acetabular component at total hip arthroplasty (THA). The purpose
of this study was to identify patients who are at risk of unfavourable
pelvic mobility, which could result in poor outcomes after THA. A consecutive series of 4042 patients undergoing THA had lateral
functional radiographs and a low-dose CT scan to measure supine
pelvic tilt, pelvic incidence, standing pelvic tilt, flexed-seated
pelvic tilt, standing lumbar lordotic angle, flexed-seated lumbar
lordotic angle, and lumbar flexion. Changes in pelvic tilt from
supine-to-standing positions and supine-to-flexed-seated positions
were determined. A change in pelvic tilt of 13° between positions was
deemed unfavourable as it alters functional anteversion by 10° and
effectively places the acetabular component outside the safe zone
of orientation.Aims
Patients and Methods
In order to address acetabular defects, porous metal revision acetabular components and augments have been developed, which require fixation to each other. The fixation technique that results in the smallest relative movement between the components, as well as its influence on the primary stability with the host bone, have not previously been determined. A total of 18 composite hemipelvises with a Paprosky IIB defect were implanted using a porous titanium 56 mm multihole acetabular component and 1 cm augment. Each acetabular component and augment was affixed to the bone using two screws, while the method of fixation between the acetabular component and augment varied for the three groups of six hemipelvises: group S, screw fixation only; group SC, screw plus cement fixation; group C, cement fixation only. The implanted hemipelvises were cyclically loaded to three different loading maxima (0.5 kN, 0.9 kN, and 1.8 kN).Objectives
Methods
Favourable results for collarless polished tapered stems have been reported, and cement creep due to taper slip may be a contributing factor. However, the ideal cement thickness around polished stems remains unknown. We investigated the influence of cement thickness on stem subsidence and cement creep. We cemented six collarless polished tapered (CPT) stems (two stems each of small, medium and large sizes) into composite femurs that had been reamed with a large CPT rasp to achieve various thicknesses of the cement mantle. Two or three tantalum balls were implanted in the proximal cement in each femur. A cyclic loading test was then performed for each stem. The migration of the balls was measured three-dimensionally, using a micro-computed tomography (CT) scanner, before and after loading. A digital displacement gauge was positioned at the stem shoulder, and stem subsidence was measured continuously by the gauge. Final stem subsidence was measured at the balls at the end of each stem.Objectives
Methods
Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm3 (standard deviation (Objectives
Materials and Methods
The purpose of this study was to compare the thickness of the hip capsule in patients with surgical hip disease, either with cam-femoroacetabular impingement (FAI) or non-FAI hip pathology, with that of asymptomatic control hips. A total of 56 hips in 55 patients underwent a 3Tesla MRI of the hip. These included 40 patients with 41 hips with arthroscopically proven hip disease (16 with cam-FAI; nine men, seven women; mean age 39 years, 22 to 58) and 25 with non-FAI chondrolabral pathology (four men, 21 women; mean age 40 years, 18 to 63) as well as 15 asymptomatic volunteers, whose hips served as controls (ten men, five women; mean age 62 years, 33 to 77). The maximal capsule thickness was measured anteriorly and superiorly, and compared within and between the three groups with a gender subanalysis using student’s Objectives
Methods
The acetabular labrum is a soft-tissue structure
which lines the acetabular rim of the hip joint. Its role in hip
joint biomechanics and joint health has been of particular interest
over the past decade. In normal hip joint biomechanics, the labrum
is crucial in retaining a layer of pressurised intra-articular fluid
for joint lubrication and load support/distribution. Its seal around
the femoral head is further regarded as a contributing to hip stability through
its suction effect. The labrum itself is also important in increasing
contact area thereby reducing contact stress. Given the labrum’s
role in normal hip joint biomechanics, surgical techniques for managing
labral damage are continuously evolving as our understanding of
its anatomy and function continue to progress. The current paper
aims to review the anatomy and biomechanical function of the labrum
and how they are affected by differing surgical techniques. Take home message: The acetabular labrum plays a critical role
in hip function and maintaining and restoring its function during
surgical intervention remain an essential goal. Cite this article:
The purpose of this study was to identify factors
that predict implant cut-out after cephalomedullary nailing of intertrochanteric
and subtrochanteric hip fractures, and to test the significance
of calcar referenced tip-apex distance (CalTAD) as a predictor for
cut-out. We retrospectively reviewed 170 consecutive fractures that had
undergone cephalomedullary nailing. Of these, 77 met the inclusion
criteria of a non-pathological fracture with a minimum of 80 days
radiological follow-up (mean 408 days; 81 days to 4.9 years). The
overall cut-out rate was 13% (10/77). The significant parameters in the univariate analysis were tip-apex
distance (TAD) (p <
0.001), CalTAD (p = 0.001), cervical angle
difference (p = 0.004), and lag screw placement in the anteroposterior
(AP) view (Parker’s ratio index) (p = 0.003). Non-significant parameters
were age (p = 0.325), gender (p = 1.000), fracture side (p = 0.507),
fracture type (AO classification) (p = 0.381), Singh Osteoporosis
Index (p = 0.575), lag screw placement in the lateral view (p =
0.123), and reduction quality (modified Baumgaertner’s method) (p = 0.575).
In the multivariate analysis, CalTAD was the only significant measurement
(p = 0.001). CalTAD had almost perfect inter-observer reliability
(interclass correlation coefficient (ICC) 0.901). Our data provide the first reported clinical evidence that CalTAD
is a predictor of cut-out. The finding of CalTAD as the only significant
parameter in the multivariate analysis, along with the univariate
significance of Parker’s ratio index in the AP view, suggest that
inferior placement of the lag screw is preferable to reduce the
rate of cut-out. Cite this article:
Many different lengths of stem are available
for use in primary total hip replacement, and the morphology of
the proximal femur varies greatly. The more recently developed shortened
stems provide a distribution of stress which closely mimics that
of the native femur. Shortening the femoral component potentially
comes at the cost of decreased initial stability. Clinical studies
on the performance of shortened cemented and cementless stems are promising,
although long-term follow-up studies are lacking. We provide an
overview of the current literature on the anatomical features of
the proximal femur and the biomechanical aspects and clinical outcomes
associated with the length of the femoral component in primary hip
replacement, and suggest a classification system for the length
of femoral stems. Cite this article:
The use of ilioischial cage reconstruction for
pelvic discontinuity has been replaced by the Trabecular Metal (Zimmer,
Warsaw, Indiana) cup-cage technique in our institution, due to the
unsatisfactory outcome of using a cage alone in this situation.
We report the outcome of 26 pelvic discontinuities in 24 patients
(20 women and four men, mean age 65 years (44 to 84)) treated by
the cup-cage technique at a mean follow-up of 82 months (12 to 113)
and compared them with a series of 19 pelvic discontinuities in
19 patients (18 women and one man, mean age 70 years (42 to 86))
treated with a cage at a mean follow-up of 69 months (1 to 170).
The clinical and radiological outcomes as well as the survivorship
of the groups were compared. In all, four of the cup-cage group
(15%) and 13 (68%) of the cage group failed due to septic or aseptic
loosening. The seven-year survivorship was 87.2% (95% confidence interval
(CI) 71 to 103) for the cup-cage group and 49.9% (95% CI 15 to 84)
for the cage-alone group (p = 0.009). There were four major complications
in the cup-cage group and nine in the cage group. Radiological union
of the discontinuity was found in all successful cases in the cup-cage
group and three of the successful cage cases. Three hips in the
cup-cage group developed early radiological migration of the components,
which stabilised with a successful outcome. Cup-cage reconstruction is a reliable technique for treating
pelvic discontinuity in mid-term follow-up and is preferred to ilioischial
cage reconstruction. If the continuity of the bone graft at the
discontinuity site is not disrupted, early migration of the components
does not necessarily result in failure. Cite this article:
The technique of femoral cement-in-cement revision
is well established, but there are no previous series reporting its
use on the acetabular side at the time of revision total hip replacement.
We describe the technique and report the outcome of 60 consecutive
acetabular cement-in-cement revisions in 59 patients at a mean follow-up
of 8.5 years (5 to 12). All had a radiologically and clinically
well-fixed acetabular cement mantle at the time of revision. During
the follow-up 29 patients died, but no hips were lost to follow-up.
The two most common indications for acetabular revision were recurrent
dislocation (46, 77%) and to complement femoral revision (12, 20%). Of the 60 hips, there were two cases of aseptic loosening of
the acetabular component (3.3%) requiring re-revision. No other
hip was clinically or radiologically loose (96.7%) at the latest
follow-up. One hip was re-revised for infection, four for recurrent
dislocation and one for disarticulation of a constrained component.
At five years the Kaplan-Meier survival rate was 100% for aseptic
loosening and 92.2% (95% CI 84.8 to 99.6), with revision for any cause
as the endpoint. These results support the use of cement-in-cement revision on
the acetabular side in appropriate cases. Theoretical advantages
include preservation of bone stock, reduced operating time, reduced
risk of complications and durable fixation.
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 use of plate-and-cable constructs to treat periprosthetic fractures around a well-fixed femoral component in total hip replacements has been reported to have high rates of failure. Our aim was to evaluate the results of a surgical treatment algorithm to use these lateral constructs reliably in Vancouver type-B1 and type-C fractures. The joint was dislocated and the stability of the femoral component was meticulously evaluated in 45 type-B1 fractures. This led to the identification of nine (20%) unstable components. The fracture was considered to be suitable for single plate-and-cable fixation by a direct reduction technique if the integrity of the medial cortex could be restored. Union was achieved in 29 of 30 fractures (97%) at a mean of 6.4 months (3 to 30) in 29 type-B1 and five type-C fractures. Three patients developed an infection and one construct failed. Using this algorithm plate-and-cable constructs can be used safely, but indirect reduction with minimal soft-tissue damage could lead to shorter times to union and lower rates of complications.
The clinical and radiological results of 50 consecutive acetabular reconstructions in 48 patients using impaction grafting have been retrospectively reviewed. A 1:1 mixture of frozen, ground irradiated bone graft and Apapore 60, a synthetic bone graft substitute, was used in all cases. There were 13 complex primary and 37 revision procedures with a mean follow-up of five years (3.4 to 7.6). The clinical survival rate was 100%, with improvements in the mean Harris Hip Scores for pain and function. Radiologically, 30 acetabular grafts showed evidence of incorporation, ten had radiolucent lines and two acetabular components migrated initially before stabilising. Acetabular reconstruction in both primary and revision surgery using a 1:1 mixture of frozen, ground, irriadiated bone and Apapore 60 appears to be a reliable method of managing acetabular defects. Longer follow-up will be required to establish whether this technique is as effective as using fresh-frozen allograft.
Cementless acetabular fixation has demonstrated superior long-term durability in total hip replacement, but most series have studied implants with porous metal surfaces. We retrospectively evaluated the results of 100 consecutive patients undergoing total hip replacement where a non-porous Allofit component was used for primary press-fit fixation. This implant is titanium alloy, grit-blasted, with a macrostructure of forged teeth and has a biradial shape. A total of 81 patients (82 hips) were evaluated at final follow-up at a mean of 10.1 years (8.9 to 11.9). The Harris Hip Score improved from a mean 53 points (23 to 73) pre-operatively to a mean of 96 points (78 to 100) at final review. The osseointegration of all acetabular components was radiologically evaluated with no evidence of loosening. The survival rate with revision of the component as the endpoint was 97.5% (95% confidence interval 94 to 100) after 11.9 years. Radiolucency was found in one DeLee-Charnley zone in four acetabular components. None of the implants required revision for aseptic loosening. Two patients were treated for infection, one requiring a two-stage revision of the implant. One femoral stem was revised for osteolysis due to the production of metal wear debris, but the acetabular shell did not require revision. This study demonstrates that a non-porous titanium acetabular component with adjunct surface fixation offers an alternative to standard porous-coated implants.
The removal of well-fixed bone cement from the femoral canal during revision of a total hip replacement (THR) can be difficult and risks the loss of excessive bone stock and perforation or fracture of the femoral shaft. Retaining the cement mantle is attractive, yet the technique of cement-in-cement revision is not widely practised. We have used this procedure at our hospital since 1989. The stems were removed to gain a better exposure for acetabular revision, to alter version or leg length, or for component incompatibility. We studied 136 hips in 134 patients and followed them up for a mean of eight years (5 to 15). A further revision was required in 35 hips (25.7%), for acetabular loosening in 26 (19.1%), sepsis in four, instability in three, femoral fracture in one and stem fracture in one. No femoral stem needed to be re-revised for aseptic loosening. A cement-in-cement revision of the femoral stem is a reliable technique in the medium term. It also reduces the risk of perforation or fracture of the femoral shaft.
Peri- and sub-prosthetic fractures, or pathological fractures below an existing well-fixed femoral component, with or without an ipsilateral knee replacement, present a difficult surgical challenge. We describe a simple solution, in which a custom-made prosthesis with a cylindrical design is cemented proximally to the stem of an existing, well-fixed femoral component. This effectively treats the fracture without sacrificing the good hip. We describe five patients with a mean age of 73 years (60 to 81) and a mean follow-up of 47 months (6 to 108). The mean overlap of the prosthesis over the femoral component was 7.5 cm (5.5 to 10). There have been no mechanical failures, no new infections and no re-operations. We suggest that in highly selected cases, in which conventional fixation is not feasible, this technique offers a durable option and avoids the morbidity of a total femoral replacement.
We assessed the outcome of patients with Vancouver type B2 and B3 periprosthetic fractures treated with femoral revision using an uncemented extensively porous-coated implant. A retrospective clinical and radiographic assessment of 22 patients with a mean follow-up of 33.7 months was performed. The mean time from the index procedure to fracture was 10.8 years. There were 17 patients with a satisfactory result. Complications in four patients included subsidence in two, deep sepsis in one, and delayed union in one. Concomitant acetabular revision was required in 19 patients. Uncemented extensively porous-coated femoral stems incorporate distally allowing stable fixation. We found good early survival rates and a low incidence of nonunion using this implant.