Conventional Hip Arthroplasty Research Articles

Metal Ion Release in Cancer Patients Following Megaprosthesis Salvage Surgery

BackgroundMegaprostheses contain many more modular components than conventional total hip and knee arthroplasty, which may lead to higher serum levels of metal ions. The aim of this study was to determine serum concentrations of titanium, chromium, and cobalt ions in cancer patients after limb salvage surgery with a megaprosthesis. MethodsA retrospective, descriptive cohort analysis consisting of patients who underwent cancer-related limb salvage surgery with a megaprosthesis at our hospital between 2010 and 2020 was conducted. Baseline and follow-up data were extracted from clinical and surgical records. Blood samples were prospectively obtained. Descriptive statistics were used for the analysis. ResultsA total of 71 patients underwent limb salvage surgery during the study period. Of these, 22 (10 women, 12 men) were included in the study. The mean age was 52 years (range, 21 to 80). Most cases (n = 16; 72.7%) involved the femur. Most patients (n = 14, 63.6%) underwent total knee megaprosthesis surgery. Implant revision surgery was required in 45% of cases (n = 10), with a mean interval of 4.32 years between the initial and revision surgeries. The mean follow-up time after revision surgery was 4.05 years. High levels of chromium were observed in 22.7% of patients (n = 5). High cobalt levels were found in 68.2% (n = 15) of patients, with toxic levels in 9.1% (n = 2). Titanium levels were high in 77.3% (n = 17) of cases and toxic in 22.7% (n = 5). Postoperative chemotherapy was significantly associated with titanium levels (P = .017). No correlation was observed between metal ion levels and time from primary or revision surgery or time from the first to revision surgery. ConclusionsThis study shows that cancer-related limb salvage surgery with megaprosthesis is associated with metal ion levels that exceed established safe thresholds. Compared to conventional hip arthroplasty, a higher proportion of the patients in this cohort presented elevated levels of metal ions. Level of evidenceIII.

Robotic-assisted versus conventional hip arthroplasty: a comparative analysis of perioperative blood management and early outcomes

Purpose: This study aimed to evaluate the impact of Robotic-Assisted Total Hip Arthroplasty (RATHA) versus Conventional Total Hip Arthroplasty (CTHA) on perioperative blood loss and blood transfusion requirements in patients with hip arthritis. Methods: This was a prospective cohort study, conducted at a high-volume tertiary care center from January 2021 to January 2023. Two hundred patients undergoing primary THA, were equally divided between RATHA (using the MAKO SmartRobotics system) and CTHA cohorts. Primary outcomes measured were perioperative hemoglobin changes, estimated blood loss (EBL), and transfusion rates. Secondary outcomes included operative times, hospital stays, and transfusion-related adverse events. Results: The mean pre-operative hemoglobin levels were comparable between the cohorts. However, the RATHA group demonstrated significantly lower post-operative day 1 hemoglobin drops, reduced EBL (1212.7 mL vs. 1565.24 mL in CTHA; p < 0.0001), and fewer transfusions (7 vs. 29 in CTHA; p < 0.0001). Operative times were shorter in the RATHA group (68.01 min vs. 77.1 min in CTHA; p < 0.0001). All robotic cohort patients were discharged within 3 days, while 14% (N = 7) of the CTHA group required extended hospital stay. Conclusion: This study demonstrates that RATHA significantly reduces perioperative blood loss, hemoglobin drop, and blood transfusion rates compared to CTHA. The observed decrease in operative time and hospital stay in the RATHA group further suggests that robotic assistance may enhance procedural efficiency and support faster patient recovery.

The association of dual-mobility total hip arthroplasty with dislocation compared to conventional hip arthroplasty for neck of femur fracture

<abstract><sec> <title>Introduction</title> <p>Neck of femur fractures are extremely common worldwide and have a mortality rate of 15% at 1 year. Dual-mobility cups (DMCs) have demonstrated a reduction in dislocation and revision rates for elective total hip arthroplasty (THA) but the benefits of DMC use in neck of femur fractures are less clear. The aim of this study was to compare the rate of dislocation between conventional and DMC THA following neck of femur fracture.</p> </sec><sec> <title>Materials and methods</title> <p>Data was retrospectively collected for patients who received either DMCs or standard acetabular components for neck of femur fractures at our institution. Patients were excluded if they had less than 2 years follow-up. Dislocation and revision rates were collected for all patients in addition to radiographic analysis to assess for loosening.</p> </sec><sec> <title>Results</title> <p>Data was collected for 39 patients with DMCs and 95 patients with conventional THA. Two patients with DMCs suffered a dislocation (5.1%) compared to 7 patients (7.3%) who underwent a conventional THA (p = 0.49). Both patients in the DMC group had additional risk factors for dislocation. One DMC patient required revision surgery for dislocation and one conventional THA patient underwent a revision for aspetic loosening. There were no cases of radiographic loosening in the DMC group.</p> </sec><sec> <title>Conclusions</title> <p>Our study showed a trend towards lower dislocation rates in patients treated with a DMC compared to conventional THA. Although there are potential issues associated with DMC implants and cost implications, this study suggests they may be advantageous in patients at high risk for dislocation.</p> </sec></abstract>

Patient-reported outcomes after hip and knee arthroplasty : results from a large national registry.

AimsThis study aims to describe the pre- and postoperative self-reported health and quality of life from a national cohort of patients undergoing elective total conventional hip arthroplasty (THA) and total knee arthroplasty (TKA) in Australia. For context, these data will be compared with patient-reported outcome measures (PROMs) data from other international nation-wide registries.MethodsBetween 2018 to 2020, and nested within a nationwide arthroplasty registry, preoperative and six-month postoperative PROMs were electronically collected from patients before and after elective THA and TKA. There were 5,228 THA and 8,299 TKA preoperative procedures as well as 3,215 THA and 4,982 TKA postoperative procedures available for analysis. Validated PROMs included the EuroQol five-dimension five-level questionnaire (EQ-5D-5L; range 0 to 100; scored worst-best health), Oxford Hip/Knee Scores (OHS/OKS; range 0 to 48; scored worst-best hip/knee function) and the 12-item Hip/Knee disability and Osteoarthritis Outcome Score (HOOS-12/KOOS-12; range 0 to 100; scored best-worst hip/knee health). Additional items included preoperative expectations, patient-perceived improvement, and postoperative satisfaction. Descriptive analyses were undertaken.ResultsFor THA and TKA patients respectively, the patient profile was 2,850 (54.5%) and 4,684 (56.4%) female, mean age 66.8 years (SD 10.6) and 67.5 (SD 8.8), and mean BMI 29.9 kg/m2 (SD 7.7) and 32.5 kg/m2 (SD 7.0). The proportion of THA and TKA patients who reported their joint as ‘much better’ was 2,946 (92.6%) and 4,020 (81.6%) respectively, and the majority of patients were ‘satisfied’ or ‘very satisfied’ with their procedure (2,754 (86.5%) and 3,981 (80.8%)). There were 311 (9.7%) of THA patients and 516 (10.5%) of TKA patients who reported ‘dissatisfied’ or ‘very dissatisfied’ with their surgery.ConclusionLarge improvements in pain, function, and overall health were evident following primary THA and TKA. Approximately 10% of patients reported dissatisfaction with their surgery. Future analyses will focus on factors contributing to dissatisfaction after arthroplasty.Cite this article: Bone Jt Open 2021;2(6):422–432.

CORR Insights®: Is the Survivorship of Birmingham Hip Resurfacing Better Than Selected Conventional Hip Arthroplasties in Men Younger Than 65 Years of Age? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

CORR Insights®: Is the Survivorship of Birmingham Hip Resurfacing Better Than Selected Conventional Hip Arthroplasties in Men Younger Than 65 Years of Age? A Study from the Australian Orthopaedic Association National Joint Replacement Registry.

Hip Spacers with a Metal-on-Cement Articulation Did Not Show Significant Surface Alterations of the Metal Femoral Head in Two-Stage Revision for Periprosthetic Joint Infection.

Two-stage revision is considered the gold standard treatment for chronic periprosthetic joint infection (PJI). During the interim period, between explantation of the infected hip endoprosthesis and revision arthroplasty, individually formed articulating hip spacers made of polymethylmethacrylate (PMMA) bone cement can be used to provide better soft tissue preservation, local antibiotic release, and improved postoperative mobilization. If effective prevention from luxation is achieved, hip function and hence overall patient satisfaction is improved. Zirconium oxide particles inside conventional PMMA bone cement, however, are known to enhance third-body wear, which may cause alterations of the metal head in the articulating spacer and hence become a serious risk for the patient. Therefore, the aim of our study was to analyze whether the articular surface of cobalt-chrome (CoCr) femoral heads is significantly altered in the setting of a metal-on-cement articulation during the interim period of two-stage revision for PJI. We analyzed a consecutive series of 23 spacer cases and compared them with femoral heads from two series of conventional hip arthroplasty revisions with metal-on-polyethylene articulations and different time intervals in situ. To investigate metallic wear, the femoral heads were thoroughly examined, and their surface roughness was measured and analyzed. We found no significant differences between the two conventional hip arthroplasty groups, despite their very different times in situ. Furthermore, the individually different times in situ within the spacer group had no significant impact on surface roughness, either. Compared with the spacer group, the surface roughness of the metal femoral heads from both conventional hip arthroplasty groups were even higher. Within the spacer group, roughness parameters did not show significant differences regarding the five predefined locations on the metal head. We conclude that metal-on-cement articulations do not cause enhanced surface alterations of the metal femoral head and hence do not limit the application in articulating hip spacers in the setting of two-stage revision for PJI.

A discrete element model to predict anatomy of the psoas muscle and path of the tendon: Design implications for total hip arthroplasty

BackgroundThe accurate estimation of a muscle's line of action is a fundamental requirement in computational modelling. We present a novel anatomical muscle wrapping technique and demonstrate its clinical use on the evaluation of the Psoas muscle mechanics in hip arthroplasty. MethodsA volume preserving, spring model to parameterize muscle anatomy changes during motion is presented. Validation was performed by a CT scan of a cadaver model in multiple positions. The predicted psoas musculotendinous path was compared with the actual imaging findings. In a second stage, psoas kinetics were compared between a conventional versus a resurfacing hip arthroplasty during gait. FindingsAnatomy prediction error was found to be 2.12 mm on average (SD 1.34 mm). When applied to psoas mechanics during walking, the muscle was found to wrap predominantly around the femoral head providing a biomechanically efficient and nearly constant moment arm for flexion during the entire gait cycle. However, this advantage was found to be lost in small diameter hip arthroplasty designs resulting in an important mechanical disadvantage. The moment arm for flexion, was on average 36% (SD 0.03%) lower in the small diameter conventional hip arthroplasty as compared to the large diameter head of the hip resurfacing and this difference was highly significant. (p < 0.001). InterpretationDespite the shortcomings of an “in silico” and cadaveric study, our findings are in accordance with previous clinical and gait studies. Furthermore, the findings are strongly in favour of large diameter implant designs, warranting their further development and optimisation.

Super PATH minimally invasive hip arthroplasty for treatment of femoral neck fractures in the elderly

Objective To evaluate the clinical efficacy of super PATH minimally invasive hip arthroplasty for the treatment of femoral neck fractures in the elderly patients. Methods From January 2014 through June 2015, 64 elderly patients with femoral neck fracture underwent hip joint replacement. Of them, 32 (15 men and 17 women with an age of 76.3±8.9 years) were treated by super PATH minimally invasive hip arthroplasty and 32 (14 men and 18 women with an age of 74.3±9.7 years) by conventional hip arthroplasty. All of them were treated through the conventional posterolateral approach. The 2 groups were compared in terms of hospital stay, operation time, change in hemoglobin on the 4th postoperative day, ambulation time, hospitalization costs, visual analogue scale (VAS) and hip Harris scores at different time points postoperatively. Results The minimally invasive group incurred significantly shorter hospital stay (8.4±1.0 d) and postoperative ambulation time (23.4±1.5 h), significantly lower hospitalization costs (48,544.9±12,336.0 yuan), and significantly higher hip Harris scores at 24 hours and one month postoperatively (75.0±5.7 points and 79.4±4.1 points) than the conventional group (10.7±1.1 d, 25.7±2.7 h, 55, 318.9±10, 896.6 yuan, 65.6±6.4 points and 75.5±3.1 points, respectively) (P 0.05). No prosthesis loosening, postoperative dislocation, periprosthetic infection or deep vein thrombosis occurred in either group during follow-up. Conclusion In the treatment of femoral neck fractures in the elderly patients, super PATH minimally invasive hip arthroplasty may be obviously advantageous over conventional replacement surgery in decreased ambulation time and hospital stay, improved short-term hip function, and reduced hospitalization costs. Key words: Arthroplasty, replacement, hip; Femoral neck fractures; Surgical procedures, minimally invasive

3D printing technology used in severe hip deformity.

This study was designed to assess the use of a 3D printing technique in total hip arthroplasty (THA) for severe hip deformities, where new and improved approaches are needed. THAs were performed from January 2015 to December 2016. Bioprosthesis artificial hip joints were used in both conventional and 3D printing hip arthroplasties. A total of 74 patients (57 cases undergoing conventional hip replacements and 17 undergoing 3D printing hip replacements) were followed-up for an average of 24 months. The average age of the patients was 62.7 years. Clinical data between the patients treated with different approaches were compared. Results showed that the time to postoperative weight bearing and the Harris scores of the patients in the 3D printing group were better than those for patients in the conventional hip replacement group. Unfortunately, the postoperative infection and loosening rates were higher in the 3D printing group. However, there were no significant differences in femoral neck anteversion, neck shaft, acetabular or sharp angles between ipsilateral and contralateral sides in the 3D printing group (P>0.05). The femoral neck anteversion angle was significantly different between the two sides in the conventional hip replacement group (P<0.05). Based on these results, we suggest that the 3D printing approach provides a better short-term curative effect that is more consistent with the physiological structure and anatomical characteristics of the patient, and we anticipate that its use will help improve the lives of many patients.

10-year results of the Birmingham Hip Resurfacing: a non-designer case series.

Recent controversies surrounding metal-on-metal (MoM) hip resurfacing has led to a substantial decline in its use. Despite this, there is good evidence to support the use of specific implants in select patients. A retrospective analysis of Birmingham Hip Resurfacing (BHR) patients with a minimum of 10 years follow-up was performed. Functional scoring was performed with the Oxford Hip Score (OHS) and failure was defined as revision for any cause. 111 patients underwent 121 BHR procedures. All patients had a minimum follow-up of 10 years. 70 patients (63%) were male. Mean patient age at surgery was 52.5 years (male 53.9 years, female 48.8 years). Overall survival at 10 years was 91% (97% male, 80% female). There was a statistically significant improvement in OHS postoperatively which remains at 10-year follow-up (p = <0.05). There was no significant difference in scores between the male and female groups. Revisions were most often in patients with smaller component sizes but this was not found to be statistically significant. Our results reflect that of the wider literature in that good outcomes can be obtained with this implant in a select group of patients and results are comparable to that of conventional hip arthroplasty in patients of a similar age.

CORR Insights(®): frequent femoral neck osteolysis with Birmingham mid-head resection resurfacing arthroplasty in young patients.

Where Are We Now? Mid-head resection resurfacing arthroplasty is considered a viable hip-preserving procedure that allows bone preservation to patients with an abnormal femoral head morphology and/or poor bone quality. These bone issues are generally found in younger patients (typically younger than 55 years of age) with hip osteonecrosis. The mid-head resection resurfacing may offer an alternative to conventional hip arthroplasty implants. However, there are only a few small studies with short-term followup (mean, 2 years to 3.5 years) using this particular implant that have shown high survivorship rates of 97% or greater [1-3]. To the best of my knowledge, the study by Assad and colleagues presents the longest mean followup for these prostheses. The authors found an increased risk of osteolysis of the remaining femoral neck in these patients despite 100% survivorship at a mean 6-year followup (range, 3 years to 8 years). It appears that many of these hips (at least 16%) will ultimately fail due to osteolysis based on the findings of the present study. Patients who have not been followed closely should receive careful scrutiny. Where Do We Need to Go? Such a finding raises specific concerns about the safety of this hip-preserving operation. We must ensure that we maximize the survivorship of these prostheses, by following the correct indications. Assuming that these prostheses will continue being used, we must also identify risk factors that could potentially lead to failure. The authors did an exhaustive search for osteolysis or failure. Unfortunately, they were unable to identify any factors that would portend a poor result (having evaluated gender, age, height, preoperative Oxford Hip Scores, preoperative UCLA activity scores; size of implant head, cup, or stem; and radiographic parameters such as cup inclination, stem-shaft angle, or spot welding). Since this problem appears sporadic, but common, they no longer recommend using this device. Even though this is a small study (n = 47 patients), one cannot assume that a larger study would have been more useful to identify this prosthesis as a problem and more patients at risk might pose an undue risk for this larger population. However, larger retrospective series of patients may help identify risk factor that contribute to failure. Until more risk factors for increased osteolysis of these prostheses can be established, this alarming risk of osteolysis without symptoms necessitates a carefully constructed followup plan for all patients who have received these devices. Failure to do so may put these patients at risk. In fact, by the time their hips become symptomatic, these patients may have more severe osteolysis, making subsequent reconstructions more difficult and jeopardizing the functional results following reconstructions. How Do We Get There? Finding the specific risk factors of osteolysis will require several types of studies. If there are other centers with large patient cohorts, it would behoove them to analyze their data to determine who might be a “safe” population and who is at high risk and needs to be evaluated more frequently. Any retrospective study must be large in order to (1) appropriately analyze those patients with osteolysis and (2) determine if there are any patient- or surgery-related factors that may be associated with increased risk. This may require the collaboration of multiple high-volume institutions with surgeons who still perform these procedures, or analysis of a national registry where these procedures are being performed. All patients should be followed on a frequent basis with: (1) Histories and physicals, (2) metal ion analyses, and (3) multiple imaging modalities including MRI or ultrasound.

The use of the Gait Deviation Index for the evaluation of participants following total hip arthroplasty: An explorative randomized trial

IntroductionIn this paper, the Gait Deviation Index (GDI) was used as a convenient method to evaluate pre-to-postoperative gait pattern changes after total hip arthroplasty and identify factors which might be predictive of outcome. DesignThree-dimensional gait data from a randomized clinical trial was used to determine changes in gait quality in participants walking at self-selected speed. Upon completion of the first assessment, the participants were randomly assigned to either resurfacing hip arthroplasty or conventional hip arthroplasty. The outcome was changes in overall gait ‘quality’ measured with GDI during the 6-month post-surgery follow-up period. Results38 participants with severe unilateral primary hip osteoarthritis took part in the trial. We found no difference in change scores between the two treatment groups; 1.9 [95%CI: −0.3 to 4.0] or between change scores for the non-operated and the operated limbs; 0.3 [95%CI: −2.3 to 1.7]. However, the score for the two groups (pooled data) improved after surgery by 4.4 [95%CI: 1.8–7.0]. The single level regression analysis identified the preoperative GDI score as a strong predictor of outcome (p<0.001). ConclusionSix months after surgery, there was no additional effect of resurfacing hip arthroplasty on GDI scores compared with conventional hip arthroplasty. Participants with the most pathological preoperative gait pattern improved the most. The GDI increased, which indicates an overall improvement in gait pathology after surgery.Trial registration: NCT01229293

Low infection rate after tumor hip arthroplasty for metastatic bone disease in a cohort treated with extended antibiotic prophylaxis.

Background. Compared to conventional hip arthroplasty, endoprosthetic reconstruction after tumor resection is associated with a substantially increased risk of periprosthetic joint infection (PJI), with reported rates of around 10% in a recent systematic review. The optimal duration of antibiotic prophylaxis for this patient population remains unknown. Material and Methods. To establish the infection rate associated with prolonged antibiotic prophylaxis in our department, we performed a retrospective review of all adult patients who underwent endoprosthetic reconstruction of the proximal femur after tumor resection for metastatic bone disease during a 4-year period from 2010 to 2013 (n = 105 patients). Results. Intravenous antibiotic prophylaxis was administrated for an extended duration of a mean of 7.4 days. The overall infection rate was 3.6% (4/111 implants), infection free survival was 96% at 2 years, and the risk of amputation associated with infection was 25% (1/4 patients). Discussion. Preemptive eradication of bacterial contamination may be of value in certain clinical situations, where the risk level and consequences of implant-associated infection are unacceptable. Our findings suggest that extended postoperative antibiotic prophylaxis may reduce the risk of PJI in patients undergoing tumor resection and endoprosthetic replacement for metastatic bone disease associated impending or de facto pathologic fractures of the proximal femur.

Persistent wound drainage after tumor resection and endoprosthetic reconstruction of the proximal femur.

Purpose: To examine the prevalence of prolonged wound drainage (PWD) after tumor resection and endoprosthetic reconstruction of the hip. Methods: Retrospective review of 86 consecutive patients with metastatic bone disease, malignant hematologic bone disease or bone sarcoma, treated with tumor resection and subsequent endoprosthetic reconstruction of the proximal femur, between 2010 and 2012, in a single center. Results: PWD for 7 days or more was observed in 41 cases (48%). The wounds only ceased oozing after a mean of 8.4 days, leading to prolonged administration of prophylactic antibiotics (mean 8.7 days) and length of hospital stay (mean 10.2 days). Total femur replacement, bone sarcoma and additional pelvic reconstruction were identified as significant independent risk factors for an even longer duration of PWD. Conclusion: Compared to conventional hip arthroplasty, PWD appears to be significantly more prevalent in patients undergoing tumor arthroplasty procedures of the hip. Given the potentially increased risk for periprosthetic joint infection (PJI), increased awareness, identification and implementation of adequate strategies for prevention and treatment of this avoidable complication are warranted.

Accuracy of an adjustable patient-specific guide for acetabular alignment in hip replacement surgery (Optihip).

Implant malalignment in hip arthroplasty increases the risk of revision surgery due to problems such as hip instability, wear, and impingement. Traditional instrumentation lacks accuracy and does not individualize the goal. Computer-assisted surgery (CAS) and patient-specific solutions improve accuracy but add considerably to the cost, amongst other drawbacks. We developed an adjustable mechanical device, called Optihip, which is set to a patient-specific goal preoperatively and is independent of pelvis position intraoperatively. The purpose of the present study was to evaluate Optihip's accuracy ex vivo. Acetabular components were implanted into six cadaveric specimens, 12 hips, by two surgeons, with the device individually adjusted according to preoperative templating on computed tomography (CT) images relative to defined acetabular rim landmarks; options also exist for templating on single or biplanar X-rays. Intraoperatively, the device was positioned on the corresponding anatomical landmarks allowing the insertion of a guide pin, which then defined the desired orientation of the acetabular cup during impaction. Mean absolute difference between the preoperatively planned cup alignment and final acetabular cup orientation, measured from postoperative CT images, was 2.5±1.2° for inclination and 2.5±2.2° for version with maximum values of 4.7° and 6.8°, respectively. Compared with previous in vivo reports, Optihip guided the acetabular cup orientation more accurately than conventional hip arthroplasty, and comparably to CAS or patient-specific systems, while fitting into the normal surgical workflow. Although clinical testing is required to confirm these experimental results, the positive ex vivo accuracy suggests good potential for improving revision rates and patient functional outcome.

Self-reported neurological clinical manifestations of metal toxicity in metal-on-metal hip arthroplasty.

Adverse reactions to metal particle debris have been increasingly reported as a complication following large head metal-on-metal (MoM) hip arthroplasty. Elevated metal ion levels are a cause for concern. The aim of this study is to evaluate whether exposure to cobalt is associated with patient characteristics and symptoms of neuropathy, representing nervous system dysfunction. A cross-sectional study was conducted comparing patients with a MoM total hip arthroplasty and patients with a conventional hip arthroplasty. They received three questionnaires, one to assess neurotoxic complaints and two standardised self-administered questionnaires to identify symptoms that are suggestive of peripheral neuropathy. Current and historical data were available for whole blood cobalt levels in all patients. We analysed potential predictive factors for cobalt based on five different cut-off levels (0-2, 2-4, 4-10, 10-20, >20 µg/L). We performed 723 MoM total hip arthroplasties in 643 patients in our clinic. The response rate was 89%. Male-female ratio was 236/280, median age 63.6 years (30-72) with a mean follow-up of 50.6 months (20-86). We also sent the questionnaires to 98 patients in the control group. An increase in the incidence of reported symptoms was not consistent with higher serum cobalt levels. Female gender was the only consistent predictive factor for serum cobalt at different cobalt cut-off levels in the multivariate analysis. The study population did not show an increase in reported symptoms with elevated cobalt levels. Neurotoxic symptoms and whole blood cobalt levels did not show a consistent relationship with different dichotomised levels of cobalt exposure.

The argument for threaded pins with a Harrington pelvic reconstruction: a case report

Metastatic bone disease is not uncommon and most orthopaedic surgeons, despite their subspecialty, will have some experience of its treatment. It is difficult to determine the incidence of metastatic bone disease; however it is estimated for all tumours at approximately 20,000 cases per year in the UK [1]. The British Orthopaedic Association have published “Metastatic Bone Disease: A Guide to Good Practice” to advise on the appropriate management of metastatic malignancy [1]. The aim of surgery in the context of metastatic disease is to palliate pain and restore function. These cases should ideally be managed within a multidisciplinary environment. Pelvic metastatic disease is not uncommon but may be managed by radiotherapy alone [1]. Peri-acetabular lesions differ, however, as they have the potential to lead to central dislocation of the hip, and therefore surgical treatment may be necessary [1]. The reconstructive options for peri-articular lesions are more involved than for other areas in the appendicular skeleton and should be discussed with the regional tumour unit and are best performed by those experienced in acetabular reconstruction. Harrington described a technique for acetabular insufficiency in 1981 which involved retrograde pins from the ilium into the acetabulumwhich were cemented with an acetabulum support with a polyethylene socket [2, 3]. Harrington described using 4.8-mm threaded Steinman pins inserted into the superior part of the ilium into healthy bone in a retrograde fashion via the same incision and in most cases across the sacroiliac joint [2]. The results of this technique have been replicated in other centres [4–7]. Tillman et al. described a modified Harrington technique using three threaded pins to provide a scaffold for the cementation of a conventional hip arthroplasty acetabular component [3]. We report a case of a modified Harrington technique using nonthreaded pins which was complicated by migration of one of the nonthreaded pins.

Outcome of hip resurfacing arthroplasty in patients with coxarthrosis secondary to Crowe′s types I and II developmental hip dysplasia

BackgroundArthritis secondary to developmental hip dysplasia is a surgical challenge because of the anatomic abnormalities, which increase the complexity of any hip arthroplasty. Hip resurfacing has many theoretical advantages compared with conventional hip arthroplasty, especially for young and active patients. These advantages include minimal bone resection, normal femoral loading, avoidance of stress shielding, maximum proprioceptive feedback, reduced risk of dislocation, easy revision, and reconstruction of normal anatomy.Patients and methodsTwenty-six consecutive patients (33 hips) with osteoarthritis secondary to developmental dysplasia of the hip of Crowe types I and II underwent metal-on-metal hip resurfacing through a modified lateral approach of Hardinge, taking care to protect the medial femoral circumflex artery and its retinacular branches over the femoral neck. The average age of the patients at the time of surgery was 62.8 years (range 30-73 years). Five (19%) patients were men and 21 (81%) were women. The mean follow-up was 4.8 years, range 1.8-10.3 years.ResultsFour patients developed heterotrophic ossification, which required excision because of persistent pain in one patient. Three patients had painful trochanteric bursitis; all responded well to local steroid injections. The Harris hip score improved from a mean of 52.2-97.4. There were no major complications, for example, dislocation, fractured neck of femur, loosening, infection, or symptomatic deep venous thrombosis.ConclusionDespite safety warnings, hip resurfacing remains an effective option in certain subgroups of hip dysplasia when it is performed with special precautions.

Is it Time for Cementless Hip Resurfacing?

Metal-on-metal bearing with cemented femoral component and cementless acetabular fixation is the current standard in surface replacement arthroplasty (RSA) of the hip. Because of concerns about the long-term survivorship of cemented stems in conventional hip arthroplasty, it seems logical to achieve cementless fixation on the femoral side with RSA. The goals of this review were to evaluate clinical and radiological data reported from previously published cementless RSA series. In addition, we intend to review author's preliminary experience with Conserve Plus cementless devices specifically assessing the clinical outcomes, the complications rate, the survivorship, and the metallic ions levels measured in follow-up. A references search was done with PubMed using the key words "cementless hip resurfacing", "cementless hip resurfacing prosthesis", and "femoral cementless hip resurfacing". Additionally, the clinical outcomes, the complications rate, the survivorship, and the metallic ions levels were measured in 94 cementless Conserve Plus(©) devices in 90 patients (68 males and 22 females) with a mean age of 41.1years (18-59). Mean follow-up was 13.1months (8-16). No revision was performed during the observed follow-up. Neither radiological signs of loosening nor neck narrowing >10% were evident. Chromium and cobalt levels in whole blood samples rose respectively from 0.53μg/l (0.1-1.7) to 1.7μg/l (0.6-2.9) and from 0.54μg/l (0.1-1.4) to 1.98μg/l (0.1-2.8). Cementless "fit and fill" femoral-side fixation, which seems to be potentially evolved and design-related, should be considered for future hip-resurfacing device generations.

Concomitant Traumatic Spinal Cord and Brachial Plexus Injuries in Adult Patients

Combined injuries to the spinal cord and brachial plexus present challenges in the detection of both injuries as well as to subsequent treatment. The purpose of this study is to describe the epidemiology and clinical factors of concomitant spinal cord injuries in patients with a known brachial plexus injury. A retrospective review was performed on all patients who were evaluated for a brachial plexus injury in a tertiary, multidisciplinary brachial plexus clinic from January 2000 to December 2008. Patients with clinical and/or imaging findings for a coexistent spinal cord injury were identified and underwent further analysis. A total of 255 adult patients were evaluated for a traumatic traction injury to the brachial plexus. We identified thirty-one patients with a combined brachial plexus and spinal cord injury, for a prevalence of 12.2%. A preganglionic brachial plexus injury had been sustained in all cases. The combined injury group had a statistically greater likelihood of having a supraclavicular vascular injury (odds ratio [OR] = 22.5; 95% confidence interval [CI] = 1.9, 271.9) and a cervical spine fracture (OR = 3.44; 95% CI = 1.6, 7.5). These patients were also more likely to exhibit a Horner sign (OR = 3.2; 95% CI = 1.5, 7.2) and phrenic nerve dysfunction (OR = 2.5; 95% CI = 1.0, 5.8) compared with the group with only a brachial plexus injury. Heightened awareness for a combined spinal cord and brachial plexus injury and the presence of various associated clinical and imaging findings may aid in the early recognition of these relatively uncommon injuries.