Background. It is unclear whether the approach of hemiarthroplasty influence the outcomes in elderly patients with displaced femoral neck fractures. We conducted a randomized controlled trial to compare the direct lateral approach (DL approach) and posterolateral approach (PL approach) for hemiarthroplasty. Methods. This study included patients presenting to our hospital with displaced femoral neck fractures (Garden stage 3 or 4) from August 2010 to August 2011. 59 patients agreed the prospective study. They were randomized between the hemiarthroplasty using DL approach or PL approach. We evaluated and compared the operative time, perioperative blood loss, peri- and post-operative complications, and 5-year survival rates. Results. Thirty-two patients underwent the hemiarthroplasty using DL approach and 27 patients underwent hemiarthroplasty using PL approach. The mean operative time was 91 min in DL group and 77 min in PL group. A significant difference was observed for the mean operative times(p<0.005). The bleeding during surgery was 194 g in DL group and 180 g in PL group. The postoperative blood loss was 268 g in DL group and 264 g in PL group, no significant difference was observed postoperatively. Perioperative and postoperative complications were observed in 8 patients of DL group and 5 patients of the PL group. In DL group, perioperative complications included fracture in 1 patient, whereas postoperative complications included deep vein thrombosis in 7 patients. In PL group, postoperative complications included deep vein thrombosis in 3 patients, deep infection in 1 patient and subluxation of the outerhead in 1 patient. Two patients of DL group and 3patients of PL group suffered second hip fractures within the follow-up period, and 1 patient of PL group suffered periprosthetic fracture and treated conservatively. We identified 28 patients as dead in the follow-up period. The 5-year survival rate of DL group was 51.3% and that of PL group was 44.2%; there were not significantly different between the groups (log-rank test, p = 0.324). Conclusion. The mean operative time was significantly longer in DL groups, but peri- and post-operative complications and the surbival rate were not significantly different between the two groups. Surgical approach might not affect the outcomes of hemiarthroplasty in patients with femoral neck fractures

Background

Proper positioning of the acetabular component is critical for prevention of dislocation and excessive wear for total hip arthroplasty (THA) and hip resurfacing. Consideration of preoperative pelvic tilt (PT) may aid in acetabular component placement. The purpose of this study was to investigate how PT changes after hip resurfacing, via pre and post-operative radiographic analysis of anterior pelvic plane (APP), and whether radiographic analysis of the APP is a reproducible method for evaluating PT in resurfaced hips.

The direct lateral (or anterolateral) approaches to the hip for revision THA involve detachment of the anterior aspect of the gluteus medius from the trochanter along with a contiguous sleeve of the vastus lateralis. Anterior retraction of this flap of gluteus medius and vastus lateralis and simultaneous posterior retraction of the femur creates an interval for division of gluteus minimus and deeper capsular tissues and exposure of the joint. To enhance reattachment of this flap of the anterior portion of the gluteus medius and vastus lateralis back to the trochanter, an oblique wafer of bone can be elevated along with the muscle off of the anterolateral portion of the trochanter. This bony wafer prevents suture pull out when large nonabsorbable sutures are used around or through the fragment and passed into the bone of the trochanteric bed for reattachment during closure. To prevent excessive splitting proximally into the gluteus medius muscle (and resulting damage to the superior gluteal nerve), it is often helpful to extend the muscle split further distally down into the vastus lateralis. This combined with careful elevation of the gluteal muscles off of the ilium (instead of splitting them) helps provide excellent and safe exposure of the entire rim of the acetabulum and access to the supracetabular region for bone grafting, acetabular augment placement and even fixation of the flanges of a cage.

A simple method for posterior column plating via the anterolateral approach involves contouring of the distal end of the plate around the base of the ischium at the inferior edge of the socket.

When an extended osteotomy of the femur is needed to correct deformity, remove a well-fixed implant or cement, the “extensile” variation of this same surgical approach involves a Wagner style (lateral to medial) osteotomy of the greater trochanter and proximal femur. The anterior portion of the femur after it is osteotomised is elevated as a separate segment while maintaining the soft tissue attachments to the bone as much as possible to aid osteotomy healing. After implant or cement removal, this approach gives excellent direct access to the distal femur for placement of a long stem revision femoral component without bone-implant conflict proximally because of the bow of the femur.

The anterolateral approach (and extensile variants detailed above) can be used routinely and safely in the full range of revision THA procedures, or it can be employed selectively, if desired, in cases at increased risk for dislocation.

Introduction. Many authors have described component position and leg length discrepancy (LLD) after total hip arthroplasty (THA) as the most important factors for good postoperative outcomes. However, regarding the relationships between component position and different approaches for THA, the optimal approach for component position and LLD remains unknown. The aims of this study were to compare these factors among the direct anterior, posterolateral, and direct lateral approaches on postoperative radiographs retrospectively, and determine which approach leads to good orientation in THA. Methods. We retrospectively evaluated 150 patients who underwent unilateral primary THA in our department between January 2009 and December 2014, with the direct anterior, posterolateral, or direct lateral approach used in 50 patients each. Patients with significant hip dysplasia (Crowe 3 or 4), advanced erosive arthritis, prevented osteotomy of the contralateral hip, and body mass index (BMI) of more than 30 were excluded. The mean age, sex, and preoperative diagnosis of the affected hip were equally distributed in patients who underwent THA with the different approaches. The mean BMI did not differ significantly among the groups. The radiographic measurements included cup inclination angle, dispersion of cup inclination from 40°, and LLD on an anteroposterior pelvic radiograph, and cup anteversion angle and dispersion of cup anteversion from 20° on a cross-table lateral radiograph postoperatively. We also measured the ratios of patients with both cup inclination of 30–50° and cup anteversion of 10–30° (target zone in our department), femoral stem varus/valgus, and LLD of 10 mm or less. Statistical analyses used an unpaired t-test and Fisher's exact test, with significance set at p<0.05. Results. The mean cup inclination was 36.9±5.1° for direct anterior approach, 40.8±7.5° for posterolateral approach, and 38.5±7.5° for direct lateral approach. Dispersion of cup inclination from 40° was almost identical in the three groups, with no significant differences. The mean cup anteversion was 23.4±5.5° for direct anterior approach, 25.9±9.2° for posterolateral approach, and 24.3±8.6° for direct lateral approach. Dispersion of cup anteversion from 20° differed between direct anterior approach and posterolateral or direct lateral approach (P<0.05 for each). The mean LLD was 1.3±6.6mm for direct anterior approach, 3.0±8.6mm for posterolateral approach, and 2.6±7.4mm for direct lateral approach. The mean LLD did not differ significantly among the three groups. The ratio of patients with both cup inclination of 30–50° and cup anteversion of 10–30° was significantly better for direct anterior approach than for posterolateral or direct lateral approach (78% vs. 52% and 52%, respectively; p<0.05). The ratios of femoral stem varus/valgus and LLD of 10 mm or less did not differ among the groups. Conclusions. The direct anterior approach in THA appeared to have small dispersion of cup anteversion angle and high ratio of cup component position in our target zone compared with the posterolateral and direct lateral approaches. However, the LLD and femoral stem varus/valgus after THA did not differ significantly among the three approaches postoperatively

Anterior surgical approaches for total hip arthroplasty (THA) have increased popularity due to expected faster recovery and less pain. However, the direct anterior approach (Heuter approach which has been popularised by Matta) has been associated with a higher rate of early revisions than other approaches due to femoral component loosening and fractures. It is also noted to have a long learning curve and other unique complications like anterior femoral cutaneous and femoral nerve injuries. Most surgeons performing this approach will require the use of an expensive special operating table. An alternative to the direct anterior approach is the anterior-based muscle-sparing approach. It is also known as the modified Watson-Jones approach, anterolateral muscle-sparing approach, minimally invasive anterolateral approach and the Röttinger approach. With this technique, the hip joint is approached through the muscle interval between the tensor fascia lata and the gluteal muscles, as opposed to the direct anterior approach which is between the sartorius and rectus femoris and the tensor fascia lata. This approach places the femoral nerve at less risk for injury. I perform this technique in the lateral decubitus position, but it can also be performed in the supine position. An inexpensive home-made laminated L-shaped board is clamped on end of table allowing the ipsilateral leg to extend, adduct, and externally rotate during the femoral preparation. This approach for THA has been reported to produce excellent results. One study reports a complication rate of 0.6% femoral fracture rate and 0.4% revision rate for femoral stem loosening. In a prospective randomised trial looking at the learning curve with new approach, the anterior-based muscle-sparing anterior approach had lower complications than a direct anterior approach. The complications and mean operative time with this approach are reported to be no different than a direct lateral approach. Since this surgical approach is not through an internervous interval, a concern is that this may result in a permanent functional defect as result of injury to the superior gluteal nerve. At a median follow-up of 9.3 months, a MRI study showed 42% of patients with this approach had fat replacement of the tensor fascia lata, which is thought to be irreversible. The clinical significance remains unclear, and inconsequential in my experience. A comparison MRI study showed that there was more damage and atrophy to the gluteus medius muscle with a direct lateral approach at 3 and 12 months. My anecdotal experience is that there is faster recovery and less early pain with this approach. A study of the first 57 patients I performed showed significantly less pain and faster recovery in the first six weeks in patients performed with the anterior-based muscle-sparing approach when compared to a matched cohort of THA patients performed with a direct lateral approach. From 2004 to 2017, I have performed 1308 total hip replacements with the anterior-based muscle sparing approach. Alternatively, I will use the direct lateral approach for patients with stiff hips with significant flexion and/or external rotation contractures where I anticipate difficulty with femoral exposure, osteoporotic femurs due to increased risk of intraoperative trochanteric fractures, previously operated hips with scarring or retained hardware, and Crowe III-IV dysplastic hips when there may be a need for a femoral shortening or derotational osteotomy. Complications have been very infrequent. This approach is a viable alternative to the direct anterior approach for patients desiring a fast recovery. The anterior-based muscle-sparing approach is the approach that I currently use for all outpatient total hip surgeries

Traditional risk factors for post-operative neuropathy include learning curve of surgical approach, DDH, and significant leg lengthening (>1 inch). Despite these risk factors, the most common scenario of a neuropathy is in a routine THA, by an experienced surgeon, for osteoarthritis, with no leg lengthening. Post-operative hematoma can lead to nerve compression, albeit rarely. The usual clinical presentation is of an acute event, with a previously intact nerve, sometime within the first days of surgery. Once diagnosed, immediate surgical decompression should be performed. Sciatic neuropathy is the most common, regardless of surgical approach, but the posterior approach poses the highest risk. Routine gluteus maximus tendon release may help to reduce the risk. When seen in the PACU, our approach is to immediately perform CT imaging to evaluate nerve integrity or to check on acetabular screw position. If no underlying cause is identified, the patient will be managed conservatively with foot orthotics and monitored for recovery. Femoral nerve palsy (FNP) can result in significant initial disability. Fortunately most patients recover function (although it can take over 18 months). In the early post-operative period it is often diagnosed after a patient complains of the leg giving away while attempting to walk. A knee brace will assist the patient with mobilization while the nerve recovers. The highest incidence of FNP is described for the direct lateral approach. Superior gluteal nerve (SGN) palsy is related to the direct lateral approach and may be avoided if the gluteus medius split is made within the safe zone (<5 centimeters from the tip of the greater trochanter). While early post-operative limp is common after the direct lateral approach, the true reported incidence of SGN palsy is low. Few studies showed that the persistent positive Trendelenburg test and limp is not exclusively related to the SGN damage and therefore the clinical effect of the SGN damage remains controversial. Lateral femoral cutaneous nerve can be affected during the direct anterior hip approach. One study suggests the presence of peri-incisional numbness in over 80% of patients. This is akin to numbness seen lateral to the incision after TKA. The incidence of meralgia paresthetica is extremely low (<1%)

Purpose. The purpose of this study was to compare and evaluate the cost-effectiveness of the MIS Anterolateral Approach to that of the MIS Posterolateral and MIS Direct Lateral Approach. Method. A prospective randomized control trial was designed and conducted to compare the MIS Anterolateral Approach to that of the MIS Posterolateral and MIS Direct Lateral Approach. Contemporary methods for economic evaluation were used to ascertain direct and indirect costs (in Canadian dollars) along with clinical effectiveness outcomes (SF6D and Pat5D utility measures). University and hospital ethics was obtained and patients were recruited and consented to participate in the RCT resulting in the assignment of 130 patients MIS hip arthroplasty procedures. Baseline patient demographics, comorbidity, quality of life, and utility were obtained for all patients. In-hospital costing data was obtained including operating room and patient room costs as well as medication, rehab and complications. Post-discharge costs were calculated from direct and indirect costs of medication, rehab, medical costs and complications until one year post-operatively. Clinical effectiveness measures were administered at intervals until one year post-operatively. Results. Patient groupings were similar pre-operatively with regards to demographic variables and quality of life measures (WOMAC, SF36, Pat5D). Post-operatively comparison of costs and complications were not different across the different surgical approaches (p>.05). Cost-effectiveness analyses (cost/QALY) were not statistically different (p>.05) when comparing the three MIS hip arthroplasty procedures. Conclusion. Primary total hip arthroplasty is a cost-effective surgical procedure and compares favorably with other health interventions. Our study is among the first to compare the cost-effectiveness of different MIS surgical approaches using contemporary methods of cost-effectiveness analyses. Our data suggests that the MIS Anterolateral approach is not superior to the MIS Posterolateral or MIS Direct Lateral approach with regards to cost-effectiveness of the intervention. Our economic evaluation was sensitive to early post-op complications including dislocation and re-operation. Surgeons should select an MIS approach based on criteria including technical preference, reliable implant placement, patient safety and complication minimization

Purpose. To determine if minimally invasive surgery (MIS) for primary hip replacement surgery increases the risk of long term aseptic loosening as predicted by implant micromotion measured with radiostereometric analysis (RSA). Method. Ninety patients undergoing primary THA for osteoarthritis (exclusion criteria: post-traumatic arthritis, rheumatoid arthritis, hip dysplasia, previous hip infection) were randomized to undergo THR surgery utilizing the standard direct lateral approach (n=45; 24 male; age=58 yrs; BMI=27) or MIS via a one-incision direct lateral approach using specific instrumentation (n=45; 23 male; age=55; BMI=29). Uncemented acetabular and femoral (ProfemurZ) components were used with ceramic on ceramic bearings. The femur was marked with 9 tantalum beads placed in the greater trochanter, lesser trochanter, and femoral shaft distal to the tip of the prosthesis. Post-operative care was be standardized according to the care maps at our institution. Primary outcome measure was femoral stem MTPM (maximum total point motion) measured using Model-based RSA. Stereo supine X-rays were taken before weight bearing and 3, 6, and 12 months postoperatively. At the same time intervals Harris Hip Score, Oxford-12, WOMAC, and SF36 questionnaires were administered. Rates of infection, dislocation and revision were recorded. Results. Nine patients were lost to follow-up (4 due to missing post-op exams; 5 did not have enough beads placed during surgery). Ten patients were revised (2 due to failure of the ceramic femoral head; 8 due to long (38.5 mm) neck fractures at 17–30 months postop). There were no differences between groups for all outcome measures. Mean MTPM at 24 months was 3.0mm (SD=2.0mm) for the MIS group and 2.9mm (SD=2.1mm) for the standard group. Conclusion. No difference between groups at one year indicates MIS for uncemented primary THR through a direct lateral approach does not appear to negatively affect stability of the femoral stem. However, there was a high rate of femoral neck fracture in the study cohort that was not related to micromotion or treatment group that indicates a problem with the design of the titanium alloy modular femoral neck

Background. The direct anterior approach (DAA) for total hip arthroplasty (THA) is marketed with claims of superiority over other approaches. Femoral exposure can be technically challenging and potentially lead to early failure. We examined whether surgical approach is associated with early THA failure. Methods. A retrospective review of 478 consecutive early revision THAs within five years of primary THA at three academic centers from 2011 through 2014 was performed. Exclusion criteria resulted in a final analysis sample of 341 early failure THAs. Primary surgical approach was documented for each revision, along with time to revision, and failure etiology. Results. Early femoral component failure was more common with the DAA (49.6%) than the direct lateral (36.6%) and posterior (13.8%) approaches (p = 0.001). In multivariate regression controlling for age, sex, laterality, Dorr bone type, BMI at revision, bilateral procedure (yes/no), and femoral stem type, the DAA remained a significant predictor of early femoral failure (p = 0.001). The majority of early revisions for instability were associated with the posterior approach (47.5%) and the DAA (37.5%) compared to the direct lateral approach (15.9%, p = 0.0002). Conclusions. Despite claims of early recovery and improved outcomes with the DAA, our findings indicate the DAA likely confers greater risk for early femoral failure and, along with the posterior approach, a greater risk of early instability compared to the direct lateral approach following THA

The dual mobility design concept for acetabular components is intended to reduce the risk of dislocation and increase range of motion, but the wear pattern of this design is unclear and may have implications in implant fixation. Additionally, the solid back cups do not have the option for supplementary screw fixation, providing an additional smooth articulating surface for the liner to move against. The objective of this study was to assess cup fixation by measuring implant migration as well as proximal femoral head penetration to evaluate wear performance. Thirty subjects were recruited in a consecutive series prospective study and received dual mobility uncemented acetabular components with mobile bearing polyethylene liners through a direct lateral approach. Femoral stems were cemented or uncemented. All subjects had 28 mm femoral heads. The femur, acetabulum, and non-articulating surface of the mobile polyethylene liner were marked with tantalum beads. Radiostereometric analysis (RSA) exams were performed post-operatively and at 6 weeks, 3 months, 6 months, 1 year, 2 years, and 3 years. Oxford 12 Hip and Satisfaction questionnaire responses were recorded. Mobile bearing motion was assessed under fluoroscopy for a single case under loaded and unloaded conditions. Twenty-nine subjects (17 female) proceeded to surgery. Subjects were 63±11 years of age with BMIs of 28±4.7 kg/m2. Cup migration reached 0.16 ± 0.31 mm of proximal translation and 0.29±1.03 degrees of sagittal rotation at three years. A single individual had more than 3 degrees of cup rotation, occurring by 6 months and not substantially increasing after this time. Proximal translation was low for this subject. Wear of the highly cross-linked mobile bearings was 0.18 ± 0.30 mm of proximal femoral head penetration from 0 to 3 years. The mean wear rate from 1 to 3 years was 0.02 mm/year. One subject was an outlier for wear, with more than 1 mm of femoral head penetration at 1 year. However, wear did not increase after 1 year for this subject and cup migrations were below average for this individual. Similarly, the outlier for cup rotation had below average wear. Satisfaction (out of 100%) improved from 25±27% to 96±7% pre-operatively to 3 years post-operatively. Oxford 12 scores (best possible score of 48) improved from 21±7 to 43±7 over the same period. The fluoroscopic case study demonstrated visible motion of the mobile bearing during hip rotation tasks. The overall migration of the cup was low and demonstrated favorable patterns suggesting low risk of aseptic loosening. Wear rates are also within the expected range of 0 to 0.06 mm/year for highly cross-linked polyethylene. The combination of low subsidence and low sagittal rotations of the cup, and low wear of the polyethylene are favorable predictors of good long-term performance

Introduction. The global rapid growth of the aging population has some likelihood to create a serious crisis on health-care and economy at an unprecedented pace. To extend Healthy Life Expectancy (HALE) in a number of countries, it is desired more than ever to investigate characteristic and prognosis of numerous diseases. This enlightenment and recent studies on patient-reported outcome measures (PROMs) will drive the increasing interest in the quality of life among the world. The demand for primary THAs by 2030 would rise up to 174% in USA. It is expected that the number of the elderly will surge significantly in the future, thus more septuagenarian and octogenarian are undergoing THA. Moreover, HALE of Japanese female near the age of 75 years, followed to Singapore, is still increasing. Therefore, concerns exist about the PROMs of performing THA in this age-group worldwide. Nevertheless almost the well-established procedure, little agreement has been reached to the elderly. We aimed to clarify the mid-term PROMs after THA over 75-year old. Methods. Between 2005 and 2013, we performed 720 consecutive primary cemented THAs through a direct lateral approach. Of these, 503 female patients (655 hips) underwent THA for treatment of osteoarthritis, with a minimum follow-up of 5 years, were retrospectively enrolled into the study. We excluded 191 patients (252 hips) aged less than 65-year at the time of surgery and 58 patients (60) because of post-traumatic arthritis or previous surgery (37), or lack of data (23). Thus, 343 hips remained eligible for our study, contributed by 254 patients. We investigated Quality-adjusted life year (QALY), EuroQol 5-Dimension 5-Level scale (EQ-5D) and the Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ, which was a disease-specific and self-administered questionnaire, reflecting the specificity of the Japanese cultural lifestyle) in patients aged 75 years or older (154 hips, Group-E) compared with those aged 65 to 74 years (189 hips, Group-C) retrospectively. We evaluated the association between patients aged 75 years or older and the following potential risk factors, using logistic regression analysis: age, number of vertebral fractures (VFs), American Society of Anesthesiologists physical status (ASA-PS) and Charlson Comorbidity Index (CCI). A p value of < 0.05 was considered significant for the Mann-Whitney U test. Results. At a mean follow-up duration of 7.2 years, QALY, EQ-5D and JHEQ for the domain of patient satisfaction were significantly greater for Group-E than Group-C; however, there were no significant differences in JHEQ for pain, movement and mental-health between groups. On multivariate analysis, the age (odds ratio [OR] 2.48, p < .01 for EQ-5D; OR .32, p < .01 for JHEQ satisfaction), VFs (OR 1.63, p < .01 for satisfaction) and ASA-PS (OR .64, p = .31 for EQ-5D) were independent predictive risk factors for patients aged 75-year or older. Conclusions. Based on mid-term follow-up of PROMs study, we suggest that cemented THA can lead to the extension of HALE towards the super aged society and our results can be applied to a systematic analysis for the Global Burden of Disease Study related frailty

The purpose of our study was to prospectively examine early functional differences in gait between the direct anterior and direct lateral surgical approaches for total hip arthroplasty over the first three months postoperatively. Forty participants were prospectively enrolled to either the direct anterior (20 patients) or direct lateral group (20 patients) based on their surgeon's expertise. Outcome measures were collected preoperatively at their preadmission appointment and postoperatively at discharge from the hospital, two weeks, six weeks and three months. We used the GAITRite® system to measure gait velocity, stride length, single-limb support and single-limb support symmetry. We also had participants complete the Timed Up and Go test and a series of questionnaires at each visit: WOMAC, SF-12, Harris Hip Score, and pain VAS. Our primary outcome, gait velocity, was significantly greater in the direct anterior group at discharge and six weeks postoperatively with adjusted mean differences of 0.12m/s and 0.17m/s respectively. Single-limb support symmetry was also significantly better in the direct anterior group at two weeks, six weeks and three months with adjusted mean differences of 0.10, 0.09 and 0.04 respectively. The direct anterior group also had significantly shorter times to complete the Timed Up and Go test at two and six weeks with adjusted mean differences of −9.02s and −2.64s. There were no differences between the groups at any time point for the WOMAC, SF-12, Harris Hip Score, or pain VAS. Preliminary results of our expertise-based study have found the direct anterior approach to total hip arthroplasty offers better early functional outcomes than the direct lateral approach

Introduction. Failure of intertrochanteric fracture fixation often occurs in patients, who have poor bone quality, severe osteoporosis, or unstable fracture patterns. Hip arthroplasty is a good replacement procedure even though it involves technical issues such as implant removal, bone loss, poor bone quality, trochanteric nonunion and difficulty of surgical exposure. The purpose of this study is to evaluate the outcomes of total hip arthroplasty (THA) as the replacement for failed fixation of intertrochanteric fractures of the femur. Patients and Methods. 203 patients of failed intertrochanteric fractures between April 2009 and October 2014 were included in the study. All of them underwent total hip arthroplasty through direct lateral approach. 150 patients were male (73.8%) and 53 patients (26.1%) were female and the mean of age was 59.02±10.34 years old (range: 56–90 years). The indications of the failure were nail cut out in 174 (85.7%), non-union in 15 (7.3%), plate failure in 14 cases (6.8%). One patient underwent two-stage protocol due to infection. We evaluated the possible clinical and radiological complications and measured functional outcome with modified Harris hip score (MHHS). We used cementless cup in nearly all of patients (95.2%), cementless long stem in 88.1% of patients. Results. We followed patients for the mean time of 4.43±1.11 years (range 3–5 years). The mean (MHHS) was improved from 45.32±12.41 (range 40–49) to 89.37±7.41 (range 85–98) significantly (P=0.002). There was no infection, no reoperation, no dislocation, no nerve palsy, no avascular necrosis, no pulmonary embolism (PTE) and deep vein thrombosis (DVT). There was only one intra-operative fracture which was treated. All patients were ambulatory at the final follow up. There were no significant differences in hospital stay, operating time, and transfusion volume between the 2 groups (P>0.05). Conclusions. We showed in a large population study that functional outcome can be achieved by hip arthroplasty excellently in elderly patients with failed intertrochanteric fractures. Though technically demanding, properly performed hip arthroplasty can be a good replacement option for this patient group

Direct anterior approach (DAA) using the Hueter interval for total hip replacement (THA) provides an inter-nervous and inter-muscular access to the hip joint. Although it is technically demanding, the learning curve has been shown to be around 40 cases and 6 months in a high-volume joint surgeon's practice. A level-one study has demonstrated that DAA provides equal or better results and an equivalent rate of complications when compared to the highly utilized direct lateral approach. Using the available evidence to perform a multi-criteria decision analysis we demonstrated that DAA can be the most efficient approach to perform THA. From our standpoint, there is no reason to speculate a surgical approach with such advantages will be abandoned in the future. The DAA is here to stay, and may become the gold standard for THA

Mini-incision total hip arthroplasty seeks to eliminate some complications of traditional extensile exposure and also facilitates more rapid post-operative rehabilitation. Posterior approach has been associated with increased risk of posterior dislocation. Thus, a modified mini-incision lateral approach of Hardinge was described not only to overcome this problem by preserving the posterior capsule, but also allows adequate access for orientation of the implant. The author has modified the Hardinge approach by a V-shaped incision where the apex is centered over the tip of the greater trochanter with the one limb extending proximally along the fibers of the gluteus medius muscle and the distal limb extending across the proximal part of vastus lateralis. This innovative surgical approach is described in this article. Conclusion. Larger incisions and surgical approaches have been associated with larger blood loss, greater need for perioperative transfusion, use of more postoperative analgesics, a longer hospital stay, and a slower recovery. In this modified approach, the gluteus medius is left intact. The postoperative strength of the abductors of the operated side was the same as that on the non-operated side and functionally, the direct lateral approach was a safe alternative to other approaches in decreasing the trendelenburg gait and incidence of heterotrophic ossification

Introduction. The dual mobility design concept for acetabular liners is intended to reduce the risk of dislocation and increase range of motion, but the wear pattern of this design is unclear and may have implications in implant fixation. Additionally, the solid back cups do not have the option for supplementary screw fixation, providing an additional smooth articulating surface for the liner to move against. The objective of this study was to assess cup fixation by measuring implant migration. A secondary objective was to evaluate the mobile bearing motion after rotating the hip. Methods. Thirty subjects were recruited in a consecutive series prospective study and received Anatomic Dual Mobility (Stryker Orthopedics) uncemented acetabular components with mobile bearing polyethylene liners through a direct lateral approach. Femoral stems were cemented (Exeter) or uncemented (Accolade, Stryker Orthopedics). The femur, acetabulum, and non-articulating surface of the polyethylene liner were marked with tantalum beads. Radiostereometric analysis (RSA) exams were performed post-operatively and at 6 weeks, 3, 6, months, and at 1 year. At the 1 year exam, a frog leg RSA exam was performed to assess the mobility of the cup compared to its position during a supine exam. Results. Proximal translation of the cup was 0.16 ± 0.28 mm (range −0.18 to 0.92 mm) and sagittal rotation was 0.08 ± 0.86 degrees (range −1.81 to 2.18 degrees) at 1 year. Analysis of the motion of the mobile bearing liner during the frog leg RSA exam showed total motions of between 0.10 to 5.58 mm (maximum total point motion). Discussion & Conclusions. The migration of the cup has a low group average and is on track to be in the “acceptable” range as defined by Pijls et al. [1] of less than 0.2 mm of subsidence at 2 years. The combination of low subsidence and low sagittal rotations of the cup are favorable predictors of good long-term performance [2]. The wide range of motions of the mobile bearing suggest that in some patients the liner is moving freely, while in a subset of subjects there is no motion. The implications of this in terms of the generation of wear particles and affect on implant migration will be monitored to 3 years

Background. Composite screws of uncalcined and unsintered hydroxyapatite (HA) particles and poly-l-lactide (PLLA) were developed as completely absorbable bone fixation devices. So far the durability of HA-PLLA composite screws is unclear when used for the fixation of acetabular bone graft in total hip arthroplasty under full-weight conditions. We have used this type of screw for the fixation of acetabular bone graft in cemented or reverse-hybrid total hip arthroplasty since 2003. Hence, we conducted a follow-up study to assess the safety and efficacy of these screws when used for cemented socket fixation. Methods. During 2003–2009, HA-PLLA composite screws were used for fixation of acetabular bone graft in cemented or reverse-hybrid primary THA in 106 patients (114 cases). All the THAs were performed through direct lateral approaches, and postoperative gait exercise with full weight bearing usually started two days after surgery. One patient died of an unrelated disease and seven patients were lost to follow-up within 5 years. Finally, 98 patients (106 cases) were followed up for over 5 years and were reviewed retrospectively (follow-up rate, 93%). Radiographic loosening of the acetabular component was assessed according to the criteria of Hodgkinson et al., and the radiolucent line around the socket was evaluated in all zones, as described by DeLee and Charnley. Results. The patient population comprised 10 men and 88 women with a mean age of 60.3 years (range, 41–81 years) at the time of surgery. The mean follow-up period was 7.6 years (range, 5–11 years). The original diagnosis for primary THA was secondary osteoarthritis in 97 cases and high hip dislocation in nine cases. No patient in this series required revision surgery, and no radiographical loosening occurred during the follow-up period. Grafted bone union was confirmed in all cases, and no apparent osteolysis around the cemented socket or composite screws was detected. Configurations of the HA-PLLA composite screws appeared obscure on radiographs at 5 years after surgery, and only osteosclerotic traces remained in the screw positions at the final follow-up. This finding was consistent in this series. The screw heads sometimes appeared to be broken with absorption within 3 years of surgery, and the remnants were identified in situ at the final follow up. Kaplan–Meier survival analyses with socket revision surgery for any reason, socket loosening, and appearance of a radiolucent line >1 mm in any zone as the endpoints yielded survival rates of 100%, 100%, and 86.8% at 5 years, and 100%, 100%, and 85.8% at 10 years, respectively. Conclusion. This absorbable screw seems to have no negative effects on the mid-term clinical results of cemented socket fixation

Introduction. The long-term wear performance of highly cross-linked polyethylene (HXLPE) in cemented total hip arthroplasty (THA) has rarely been reported. Here we report a prospective randomized comparative analysis of radiographic wear after a minimum follow-up of 10 years in cemented THAs with either HXLPE or conventional polyethylene (CPE), and assess its clinical relevance. Patients and Methods. From 1999 to 2001, we conducted 94 primary cemented THAs with a 22.225-mm head at our hospital as part of a prospective randomized trial. All surgeries were performed using a direct lateral approach with a trochanteric osteotomy (Dall's approach). The patients were divided into 4 groups. Twenty-six hips in group A were implanted with CPE sockets against zirconia heads and Charnley-type stems. HXLPE sockets (Aeonian, Kyocera Medical Corp) were implanted in all hips in the other 3 groups. Twenty-five hips in group B were implanted with zirconia heads and KC stems (Kyocera Medical Corp), 23 hips in group C with zirconia heads and distal cylindrical stems, and 20 hips in group D with stainless steel heads and C-stem (DePuy Inc). The sockets were highly cross-linked by gamma irradiation at a dose of 35 kGy, heat annealed at 110ºC, and sterilized with 25 kGy of gamma irradiation in nitrogen. For radiographic evaluation, anteroposterior radiograms were taken for each patient annually, and every two years postoperatively for wear analyses. Two-dimensional head penetration was measured on each postoperative radiogram using a computer-aided technique. Results. Wear measurements were performed for 59 cases followed up over 10 years. Linear wear rates were 0.138±0.074 (mm/year±SD) for group A, 0.010±0.015 for group B, 0.013±0.020 for group C, and 0.012±0.027 for group D. Linear wear rates differed significantly between group A and other groups, and no significant difference was found among groups B, C, and D. There were four revision cases. Among them, two sockets of group A were revised for aseptic loosening at 7 and 14 years postoperatively with linear wear rates of 0.749 and 0.153 mm, respectively. Two stems of group B and C were revised for aseptic loosening at 10 and 9 years postoperatively with linear wear rates of 0.007 and 0.041 mm, respectively. There were no other cases with aseptic loosening in any group. Osteolysis was found in 10 cases (group A: 7, group B: 1, group C: 1, group D: 1), and there was a significant difference in linear wear rates between the cases with and without osteolysis (0.157±0.083 and 0.030±0.053 mm/year±SD respectively). Discussion. The two revision cases of HXLPE did not have aggressive socket wear, and possibly cement fracture caused osteolysis and stem instability. The results of this study indicate that there is a significant difference in wear rate between CPE and HXLPE, and it was evident that PE wear was associated with osteolysis and aseptic loosening of the socket

Heterotopic ossification (HO) is the formation of bone at extra-skeletal sites. Genetic diseases, traumatic injuries, or severe burns can induce this pathological condition and can lead to severe immobility. While the mechanisms by which the bony lesions arise are not completely understood, intense inflammation associated with musculoskeletal injury and/or highly invasive orthopaedic surgery is thought to induce HO. The incidence of HO has been reported between 3% and 90% following total hip arthroplasty. While the vast majority of these cases are asymptomatic, some patients will present decreased range of motion and painful swelling around the affected joints leading to severe immobility. In severe cases, ectopic bone formation may be involved in implant failure, leading to costly and painful revision surgery. The effects of surgical-related intraoperative risk factors for the formation of HO can also play a role. Prophylactic radiation therapy, and anti-inflammatory and biphosphonates agents have shown some promise in preventing HO, but their effects are mild to moderate at best and can be complicated with adverse effects. Irradiation around surgery could decrease the incidence of HO. However, high costs and the risk of soft tissue sarcoma inhibit the use of irradiation. Increased trials have demonstrated that nonsteroidal anti-inflammatory drugs (NSAID) are effective for the prevention of HO. However, the risk of gastrointestinal side effects caused by NSAID has drawn the attention of surgeons. The effect of the selective COX-2 inhibitor, celecoxib, is associated with a significant reduction in the incidence of HO in patients undergoing THA. Bone morphogenetic proteins (BMP) such as BMP2 identified another novel druggable target, i.e., the remote application of apyrase (ATP hydrolyzing agent) in the burn site decreased HO formation and mitigated functional impairment later. The question is if apyrase can be safely administered through other, such as systematical, routes. While the systemic treatments have shown general efficacy and are used clinically, there may be great benefit obtained from more localised treatment or from more targeted inhibitors of osteogenesis or chondrogenesis. In the surgical setting, prophylaxis for HO is regularly indicated due to the considerable risk of functional impairment. Heterotopic ossification is a well-known complication of total hip arthroplasty, especially when the direct lateral approach is used. Possible intraoperative risks are the size of incision, approach, duration of surgery and gender that can be associated with higher rates of HO or increase of the severity of HO. Like inflammation and tissue damage/ischemia are likely to be the key in the formation of HO, kindness to the soft tissues, tissue preserving surgery, pulse lavage to remove bone inducing factors and avoiding damage to all tissues should be erased as a comorbidity. Incision length, tissue dissection and subsequent localised trauma and ischemia, blood loss, anesthetic type and length of surgery may all contribute to the local inflammatory response. Data suggest that the surgeon may control the extent and nature of HO formation by limiting the incision length and if possible the length of the operation. Currently resection of HO is generally suggested after complete maturation (between 14–18 months), since earlier intervention is thought to predispose to recurrence. Reliable indicators of maturation of HO are diminishing activity on serial bone scans and/or decreasing levels of alkaline phosphatase. Although usually asymptomatic, heterotopic bone formation can cause major disability consisting of pain and a decreased range of motion in up to 7% of patients undergoing THA. Patients benefit from early resection of the heterotopic ossification with a proper and reliable postoperative strategy to prevent recurrence of HO with clinical implications

The number one reason to consider large heads in total hip arthroplasty (THA) is for increased stability. Large diameter femoral heads substantially increase stability by virtue of increased range of motion and increased jump distance, which is the amount of displacement required to sublux the head out of the socket. Prevention is the best means for reducing dislocation, with requisites for stability being appropriate component position, restoration of leg length, and restoration of offset. In a review from our center studying the frequency of dislocation with small diameter femoral heads (≤32 mm) in 1262 patients (1518 hips) who underwent primary THA performed via a direct lateral approach, we observed a dislocation rate of 0.8% (12 of 1518). In a subsequent study of 1748 patients (2020 hips) who underwent primary THA at our center with large diameter heads (mean 43 mm, range 36–60 mm), we observed a substantially lower 0.04% frequency of dislocation (one of 2010) at a mean followup of 2.6 years. Our findings have been echoed in studies from several other centers. Howie et al. reported a prospective controlled trial of 644 low risk patients undergoing primary or revision THA randomised to receive either a 36 mm or 28 mm metal head articulated on highly crosslinked polyethylene. They observed significantly lower frequency of frequency of dislocation with 36 mm heads both overall (1.3%, 4 of 299 versus 5.4%, 17 of 216 with 28 mm heads, p=0.012) and in primary use (0.8%, 2 of 258 versus 4.4%, 12 of 275 with 28 mm heads, p=0.024), and a similar trend in their smaller groups of revision patients (5%, 2 of 41, versus 12%, 5 of 41 with 28 mm heads, p=0.273). Lachiewicz and Soileau reported on early and late dislocation with 36- and 40 mm heads in 112 patients (122 hips) at presumed high risk for dislocation who underwent primary THA. Risk factors were age >75 for 80 hips, proximal femur fracture for 18, history of contralateral dislocation for 2, history of alcohol abuse in 2, large acetabulum (>60 mm) in 6, and other reasons in 14. Early dislocation (<1 year) occurred in 4% (5 of 122), all with 36 mm heads. Late dislocation (>5 years) did not occur in any of the 74 patients with followup beyond 5 years. Stroh et al. compared 225 patients (248 hips) treated with THA using small diameter heads (<36 mm) to 501 patients (559 hips) treated with THA using large diameter heads (≥36 mm). There were no dislocations with large diameter heads compared with 1.8% (10 of 559) with small diameter heads. Allen et al. studied whether or not large femoral heads improve functional outcome after primary THA via the posterior approach in 726 patients. There were 399 done with small heads (<36 mm), 254 with medium heads (36 mm), and 73 with large heads (>36 mm), analyzed pre-operatively, at 6 months, and at 12 months. The authors could not find a correlation between increasing head size and improved function at one year, but observed that dislocation was reduced with large diameter heads. Optimization of hip biomechanics via proper surgical technique, component position, and restoration of leg length and offset are mandatory in total hip arthroplasty. Large heads enhance stability by increasing range of motion prior to impingement and enhancing jump stability