Biomechanical analysis of load distribution in porcine hip joints at different acetabular coverages.

BACKGROUND: Developmental dysplasia of the hip causes secondary osteoarthritis. Finite element analysis suggests high hip joint contact pressure in patients with hip dysplasia and a reduction in contact pressure after periacetabular osteotomy. However, few biomechanical studies have examined the load distribution in the hip joint. This study aimed to investigate the biomechanical properties of load distribution in porcine hip joints at different acetabular coverages. METHODS: Six porcine hip joints were analyzed using three models: 1) neutral coverage, 2) 15° under-coverage (defined as dysplasia model), and 3) 15° over-coverage created by varying the acetabular coverage. The load distribution was assessed using a pressure-mapping sensor system after applying a loading force of 100 N to the hip joint. RESULTS: In the dysplasia model, the load was concentrated at the acetabular rim; in the neutral and over-coverage models, it was dispersed. The average contact pressure was significantly higher in the dysplasia model than in the neutral coverage model ([0.42 vs. 0.3 MPa]; p = 0.004). The contact area was significantly smaller in the dysplasia model than in the neutral coverage model ([250.7 vs. 345.0 mm2]; p = 0.004). No significant differences were observed in contact pressure or area between the neutral and over-coverage models. CONCLUSIONS: Insufficient acetabular coverage in the dysplasia model demonstrated higher contact pressure and smaller contact area than the neutral model. Conversely, the contact pressure and area in the over-coverage model did not differ significantly from those in the normal model. Therefore, surgeons should note that acetabular coverage overcorrection has limited effect; normalization is crucial during periacetabular osteotomy.

[Analysis of kinematic changes of hip joint after total hip arthroplasty].

Objective: To analyze the kinematic changes of the hip joint after total hip arthroplasty (THA) through three-dimensional gait analysis. Methods: Patients with hip joint diseases admitted between October 2022 and June 2023 were selected as the subjects. The patients who met the selective criteria were finally included in the THA group. The healthy volunteers matched with the THA group in the same age were included as the control group. Baseline data including age, gender, body mass index (BMI), and laterality were compared between the two groups. The Harris hip score (HHS) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score were recorded preoperatively and at last follow-up in the THA group. Three-dimensional motion capture system was utilized to collect spatiotemporal parameters and kinematic data during walking, including stride length, cadence, and maximum/minimum values, range of motion (ROM) in hip joint abduction/adduction, external/internal rotation, and flexion/extension, as well as gait scores. Differences between the two groups were analyzed. Additionally, the correlation between gait scores and postoperative HHS and WOMAC scores were analyzed in the THA group. Finally, the kinematic data of each degree of freedom (DOF) were fitted into a gait diagram, and the dynamic changes of the 3-DOF of the hip joint during the gait cycle were quantitatively analyzed. Results: There was no significant difference in gender, age, laterality, and BMI between the two groups ( n=20, P>0.05). The mean follow-up time in the THA group was 9.9 months (range, 6-12 months). The HHS and WOMAC scores at last follow-up in the THA group showed significant improvement when compared with preoperative scores ( P<0.05). Gait scores were positively correlated with postoperative HHS score ( r=0.585, P=0.007) and negatively correlated with WOMAC score ( r=-0.619, P=0.004). There was no significant difference in stride length and cadence between the THA and control groups ( P>0.05), but gait score was significantly lower in the THA group than in the control group ( P<0.05). There was no significant difference in maximum and minimum values of flexion/extension, external/internal rotation, and abduction/adduction between the two groups ( P>0.05); however, ROM in the THA group was significantly lower than that in the control group ( P<0.05). There were significant differences between the two groups of flexion/extension in multiple phases of the gait cycle ( P<0.05). Conclusion: Early post-THA hip joint kinematics exhibit relative adduction, external rotation, and flexion during the gait cycle compared to normal individuals, with incomplete recovery of kinematic parameters in three degrees of freedom. Significant differences in flexion are observed at multiple phases of the gait cycle compared to normal individuals.

[Medium- and long-term effectiveness of hip revision with SL-PLUS MIA stem in patients with Paprosky type â - â ¢ femoral bone defect].

Objective: To investigate the medium- and long-term effectiveness of hip revision with SL-PLUS MIA stem in patients with Paprosky typeⅠ-Ⅲ femoral bone defect. Methods: Between June 2012 and December 2018, 44 patients with Paprosky typeⅠ-Ⅲ femoral bone defect received hip revision using SL-PLUS MIA stem. There were 28 males and 16 females, with an average age of 57.7 years (range, 31-76 years). Indications for revision comprised aseptic loosening (27 cases) and periprosthetic joint infection (17 cases). The Harris hip scores were 54 (48, 60) and 43 (37, 52) in patients with aseptic loosening and periprosthetic joint infection, respectively. The preoperative femoral bone defects were identified as Paprosky type Ⅰ in 32 cases, type Ⅱ in 9 cases, type ⅢA in 2 cases, and type ⅢB in 1 case. Operation time and intraoperative blood transfusion volume were recorded. During follow-up after operation, the hip joint function were evaluated by Harris hip score and X-ray films, the femoral stem survival was analyzed, and the surgical related complications were recorded. Results: The operation time of infected patients was 95-215 minutes, with an average of 125.0 minutes. The intraoperative blood transfusion volume was 400-1 800 mL, with an average of 790.0 mL. The operation time of patients with aseptic loosening was 70-200 minutes, with an average of 121.0 minutes. The intraoperative blood transfusion volume was 400-1 400 mL, with an average of 721.7 mL. All patients were followed up 5.3-10.0 years (mean, 7.4 years). At last follow-up, the Harris hip scores were 88 (85, 90) and 85 (80, 88) in patients with aseptic loosening and periprosthetic joint infection, respectively, both of which were significantly higher than those before operation ( P<0.05). Radiological examination results showed that the distal end of the newly implanted femoral stem did not cross the distal end of the original prosthesis in 25 cases, and all femoral stems obtained bone fixation. Two cases experienced femoral stem subsidence and 1 case had a translucent line on the lateral side of the proximal femoral stem. When aseptic loosening was defined as the end event, the 10-year survival rate of the SL-PLUS MIA stem was 100%. When treatment failure due to any reason was defined as the end event, the survival time of the prosthesis was (111.70±3.66) months, and the 7-year survival rate was 95.5%. The 7-year survival rates were 94.1% and 96.3% in patients with aseptic loosening and periprosthetic joint infection, respectively. The incidence of postoperative complications was 9.1% (4/44), among which the prosthesis related complications were 4.5% (2/44), 1 case of dislocation and 1 case of infection recurrence. Conclusion: Hip revision with SL-PLUS MIA stem has the advantages of simple operation and few postoperative complications in the patients with Paprosky type Ⅰ-Ⅲ femoral bone defect, and the medium- and long-term effectiveness is reliable.

Clinical application of LARS tumor tube in joint function reconstruction of tumor type artificial hip replacement. / LARSè‚¿ç˜¤ç®¡åœ¨è‚¿ç˜¤åž‹äººå·¥é«‹å ³èŠ‚ç½®æ¢æœ¯å ³èŠ‚åŠŸèƒ½é‡å»ºä¸­çš„ä¸´åºŠåº”ç”¨.

OBJECTIVES: Proximal femur tumor resection often leads to hip joint instability and functional loss. Various methods have been clinically applied to repair hip joint soft tissue function, but deficiencies remain. This study aims to evaluate the advantages and disadvantages of the ligament advanced reinforcement system (LARS) tumor tube in assisting soft tissue function reconstruction in patients undergoing tumor type artificial hip replacement surgery. METHODS: This study included 85 patients (41 males, 44 females) with proximal femoral tumors treated at the Xiangya Bone Tumor Treatment Center from January 2012 to January 2022, aged 10 to 79 (38.5±18.2) years. Among them, 13 cases had benign aggressive tumors, 45 had primary malignant bone tumors, and 27 had bone metastases. Clinical data, imaging data, and intraoperative photos were collected. Patients were followed up and postoperative functional evaluations were conducted using the Musculoskeletal Tumor Society (MSTS) scoring system and Harris hip joint scoring system to assess limb function and hip joint function. RESULTS: Preoperative pathological fractures were present in 37 cases (43.5%), with a lesion length of (9.4±2.9) cm. Among non-metastatic tumor patients, 7 experienced postoperative recurrence, including 6 cases of osteosarcoma and 1 case of fibrosarcoma. Pulmonary metastases occurred in 9 osteosarcoma patients. Five patients required reoperation due to postoperative complications, including 3 cases of deep vein thrombosis, 1 case of giant cell granuloma, and 1 case of prosthesis infection. Postoperatively, 5 patients exhibited Trendelenburg gait, and 6 had leg length discrepancies. The postoperative MSTS score was 26.7±1.4, and the Harris score was 89.6±5.3. CONCLUSIONS: The LARS tumor tube can effectively assist in reconstructing the soft tissue function of the hip joint and greatly reduce postoperative complications, making it an effective technical improvement in joint function reconstruction in tumor type artificial hip replacement surgery.

Determination of rotation center and diameter of femoral heads using off-the-shelf augmented reality hardware for navigation.

In total hip arthroplasty (THA), determining the center of rotation (COR) and diameter of the hip joint (acetabulum and femoral head) is essential to restore patient biomechanics. This study investigates on-the-fly determination of hip COR and size, using off-the-shelf augmented reality (AR) hardware. An AR head-mounted device (HMD) was configured with inside-out infrared tracking enabling the determination of surface coordinates using a handheld stylus. Two investigators examined 10 prosthetic femoral heads and cups, and 10 human femurs. The HMD calculated the diameter and COR through sphere fitting. Results were compared to data obtained from either verified prosthetic geometry or post-hoc CT analysis. Repeated single-observer measurements showed a mean diameter error of 0.63 mm ± 0.48 mm for the prosthetic heads and 0.54 mm ± 0.39 mm for the cups. Inter-observer comparison yielded mean diameter errors of 0.28 mm ± 0.71 mm and 1.82 mm ± 1.42 mm for the heads and cups, respectively. Cadaver testing found a mean COR error of 3.09 mm ± 1.18 mm and a diameter error of 1.10 mm ± 0.90 mm. Intra- and inter-observer reliability averaged below 2 mm. AR-based surface mapping using HMD proved accurate and reliable in determining the diameter of THA components with promise in identifying COR and diameter of osteoarthritic femoral heads.

The Principles of Hip Joint Preservation.

The 3 primary factors involved with preservation of the hip joint are femoroacetabular impingement (FAI), hip dysplasia, and femoral torsion abnormalities. Each of these factors affects the health of the acetabular labrum and femoroacetabular cartilage. The appropriate surgical treatments for each of these factors include arthroscopic or open femoroplasty or acetabuloplasty for FAI, periacetabular osteotomy (PAO) for acetabular dysplasia, and de-rotational femoral osteotomy for femoral torsion abnormalities. When evaluating patients with prearthritic hip conditions, orthopaedic surgeons should be aware of the various factors involved in hip joint preservation and, if surgery is indicated, surgeons should be sure to address all factors that need surgical treatment rather than focusing on the most obvious issue or injury (e.g., a labral tear). The purpose of this infographic is to illustrate the importance of the factors involved in hip joint preservation and the appropriate treatments for pathology in any of these factors.

Effects of different slopes on hip and ankle biomechanics of replaced and non-replaced limbs of patients with total knee arthroplasty during incline ramp walking.

Although knee biomechanics has been examined, hip and ankle biomechanics in incline ramp walking has not been explored for patients with total knee arthroplasty (TKA). The purpose of this study was to investigate the hip and ankle joint kinematic and kinetic biomechanics of different incline slopes for replaced limbs and non-replaced limbs in individuals with TKA compared to healthy controls. Twenty-five patients with TKR and ten healthy controls performed walking trials on four slope conditions of level (0°), 5°, 10° and 15° on a customized instrumented ramp system. A 3x4 (limb x slope) repeated analysis of variance was used to evaluate selected variables. The results showed a greater peak ankle dorsiflexion angle in the replaced limbs compared to healthy limbs. No significant interactions or limb main effect for other ankle and hip variables. The peak dorsiflexion angle, eversion angle and dorsiflexion moment were progressively higher in each comparison from level to 15°. The peak plantarflexion moment was also increased with each increase of slopes. Both the replaced and non-replaced limbs of patients with TKA had lower hip flexion moments than the healthy control limbs. Hip angle at contact and hip extension range of motion increased with each increase of slopes. Peak hip loading-response internal extension moment increased with each increase in slope and peak hip push-off internal flexion moment decreased with each increase of slope. Our results showed increased dorsiflexion in replaced limbs but no other compensations of hip and ankle joints of replaced limbs compared to non-replaced limbs and their healthy controls during incline walking, providing further support of using incline walking in rehabilitation for patients with TKA.

Impact of graft width and chondrolabral junction preservation on labral suction seal integrity in bovine hip models.

OBJECTIVE: This study investigates the biomechanical effects of graft width and chondrolabral junction (CLJ) preservation on the labral suction seal in a bovine hip model and aims to validate this model as a practical alternative for hip biomechanical research by comparing it with human cadaver studies. MATERIALS AND METHODS: Twenty hips from two-year-old male bovines were divided into two main groups: CLJ preserved (CLJ+) and CLJ excised (CLJ-). These groups were further divided into eight subgroups: Group 1 with an intact labrum; Group 2 with labrum excision preserving CLJ; Groups 3 and 4 with labral reconstruction on preserved CLJ using 4.5 mm and 9 mm grafts, respectively; Group 5 with a labral tear at 12 to 3 o'clock position without CLJ preservation; Group 6 with complete labrum excision without CLJ preservation; and Groups 7 and 8 with labral reconstruction on excised CLJ using 4.5 mm and 9 mm grafts. Mechanical tests measuring compression and distraction forces were conducted, recording force-displacement values. RESULTS: Both CLJ+ and CLJ- groups showed that labrum excision resulted in the lowest distraction forces, emphasizing labral integrity. Notably, reconstruction with 9 mm grafts improved distraction forces more than 4.5 mm grafts (p<0.001). The change in distraction forces from intact to excised stages was nearly significant between CLJ+ and CLJ- groups (Δ Intact-excised: CLJ+ vs. CLJ-: 92 N vs. 105 N, p=0.08). Distraction forces were measured at 206±27 Newtons in the CLJ preserved group and 186±24 Newtons in the resected group. CONCLUSIONS: This study demonstrates that increasing the width of the graft, despite being approximately half and a quarter of the native labrum's size, significantly enhances the distraction force in labral reconstruction within a bovine hip model. This improvement is more pronounced than the effects of preserving the CLJ, highlighting the critical role of graft size in maintaining the biomechanical integrity of the labral suction seal.

Use of a fluoroscopy-based robotic-assisted total hip arthroplasty system resulted in greater improvements in hip-specific outcome measures at one-year compared to a CT-based robotic-assisted system.

BACKGROUND: The purpose of this study was to compare one-year patient reported outcome measures between a novel fluoroscopy-based robotic-assisted (FL-RTHA) system and an existing computerised tomography-based robotic assisted (CT-RTHA) system. METHODS: A review of 85 consecutive FL-RTHA and 125 consecutive CT-RTHA was conducted. Outcomes included one-year post-operative Veterans RAND-12 (VR-12) Physical (PCS)/Mental (MCS), Hip Disability and Osteoarthritis Outcome (HOOS) Pain/Physical Function (PS)/Joint replacement, and University of California Los Angeles (UCLA) Activity scores. RESULTS: The FL-RTHA cohort had lower pre-operative VR-12 PCS, HOOS Pain, HOOS-PS, HOOS-JR, and UCLA Activity scores compared with patients in the CT-RTHA cohort. The FL-RTHA cohort reported greater improvements in HOOS-PS scores (-41.54 vs. -36.55; p = 0.028) than the CT-RTHA cohort. Both cohorts experienced similar rates of major post-operative complications, and had similar radiographic outcomes. CONCLUSIONS: Use of the fluoroscopy-based robotic system resulted in greater improvements in HOOS-PS in one-year relative to the CT-based robotic technique.

Application of AI-assisted MRI for the identification of surgical target areas in pediatric hip and periarticular infections.

OBJECTIVE: To develop an AI-assisted MRI model to identify surgical target areas in pediatric hip and periarticular infections. METHODS: A retrospective study was conducted on the pediatric patients with hip and periarticular infections who underwent Magnetic Resonance Imaging(MRI)examinations from January 2010 to January 2023 in three hospitals in China. A total of 7970 axial Short Tau Inversion Recovery (STIR) images were selected, and the corresponding regions of osteomyelitis (label 1) and abscess (label 2) were labeled using the Labelme software. The images were randomly divided into training group, validation group, and test group at a ratio of 7:2:1. A Mask R-CNN model was constructed and optimized, and the performance of identifying label 1 and label 2 was evaluated using receiver operating characteristic (ROC) curves. Calculation of the average time it took for the model and specialists to process an image in the test group. Comparison of the accuracy of the model in the interpretation of MRI images with four orthopaedic surgeons, with statistical significance set at P < 0.05. RESULTS: A total of 275 patients were enrolled, comprising 197 males and 78 females, with an average age of 7.10 ± 3.59 years, ranging from 0.00 to 14.00 years. The area under curve (AUC), accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 1 were 0.810, 0.976, 0.995, 0.969, 0.922, and 0.957, respectively. The AUC, accuracy, sensitivity, specificity, precision, and F1 score for the model to identify label 2 were 0.890, 0.957, 0.969, 0.915, 0.976, and 0.972, respectively. The model demonstrated a significant speed advantage, taking only 0.2 s to process an image compared to average 10 s required by the specialists. The model identified osteomyelitis with an accuracy of 0.976 and abscess with an accuracy of 0.957, both statistically better than the four orthopaedic surgeons, P < 0.05. CONCLUSION: The Mask R-CNN model is reliable for identifying surgical target areas in pediatric hip and periarticular infections, offering a more convenient and rapid option. It can assist unexperienced physicians in pre-treatment assessments, reducing the risk of missed and misdiagnosis.

Long-term Survivorship and Outcomes of Patients Without Dysplasia Undergoing Capsular Repair During Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

BACKGROUND: There is a paucity of literature evaluating long-term outcomes and survivorship of patients undergoing primary hip arthroscopy with capsular repair for femoroacetabular impingement syndrome (FAIS). PURPOSE: To report 10-year survivorship and patient-reported outcomes (PROs) after primary hip arthroscopy with capsular repair for FAIS and evaluate the effect of capsular repair in patients at the highest risk for conversion to arthroplasty. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Data were prospectively collected and retrospectively reviewed on all patients undergoing primary hip arthroscopy with capsular repair between October 2008 and February 2011. Patients with a minimum 10-year follow-up on the modified Harris Hip Score (mHHS), Nonarthritic Hip Score (NAHS), and visual analog scale for pain (VAS) scores were selected. The preoperative and minimum 10-year follow-up Hip Outcome Score-Sports Specific Subscale (HOS-SSS) scores were also reported, if available. Patients with ipsilateral hip surgery, worker's compensation, Tönnis osteoarthritis grade >1, and hip dysplasia (lateral center-edge angle <25°) were excluded. Survivorship, PROS, and clinical benefit-minimal clinically important difference (MCID) and Patient Acceptable Symptom State (PASS)-were reported. An additional propensity-matched subanalysis was performed on patients at the highest risk for conversion to arthroplasty, comparing patients undergoing capsular repair to patients with unrepaired capsules. RESULTS: A total of 145 (n = 130 patients) out of 180 eligible hips (n = 165 patients) had a minimum 10-year follow-up (80.6%). Also, 126 hips (86.9%) belonged to women, and 19 hips (13.1%) belonged to men. The mean patient age was 30.3 ± 12.9 years. The survivorship rate was 91% at the 10-year follow-up. The cohort experienced significant improvements (P < .001) in the mHHS, NAHS, HOS-SSS, and VAS for pain scores. Moreover, the cohort achieved high rates of the PASS for the mHHS (89.8%), high rates of the MCID for the mHHS (82.4%), and high rates of the MCID for VAS for pain (80.6%) scores. In the propensity-matched subanalysis performed on patients with the highest risk for arthroplasty, 29 hips with capsular repair were matched to 81 hips with unrepaired capsules. While both groups experienced significant improvements in all PROs (P < .05), the group without capsule repair trended toward a higher conversion to arthroplasty rate when compared with the repair group. In addition, an odds ratio was calculated for the likelihood of converting to arthroplasty after having an unrepaired capsule compared with capsular repair (2.54 [95% CI, 0.873-7.37]; P = .087). CONCLUSION: Patients undergoing primary hip arthroscopy with capsular repair experienced a high survivorship rate of 91% at a minimum 10-year follow-up. Patients who did not convert to arthroplasty saw favorable improvements in PROs and achieved high clinical benefit rates. In addition, among those patients at the highest risk for conversion to arthroplasty, a trend toward greater survivorship was observed with capsular repair.

Predictors of Clinical Outcomes After Hip Arthroscopy: 10-Year Follow-up Analysis of 1038 Patients.

BACKGROUND: Although hip arthroscopy has been shown to have beneficial outcomes, there is a paucity of literature examining predictive factors of 10-year clinical outcomes. PURPOSE: (1) To identify predictive factors of 10-year outcomes of hip arthroscopy and (2) to compare these factors with those found in 2-year and 5-year studies. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Data were prospectively collected and retrospectively reviewed on all patients undergoing hip arthroscopy between February 2008 and June 2012. Patients were included if they had a minimum 10-year follow-up on 2 patient-reported outcome measures: Nonarthritic Hip Score (NAHS) and modified Harris Hip Score. Exclusion criteria included previous ipsilateral hip conditions. Using bivariate and multivariate analyses, that authors analyzed the effects of 37 pre- and intraoperative variables on the NAHS, modified Harris Hip Score, and conversion to total hip arthroplasty. RESULTS: Of the 883 patients who met the inclusion criteria, 734 (83.1%) had follow-up data. The mean follow-up time was 124.4 months (range, 120.0-153.1 months). Six variables were significant predictors of NAHS in both multivariate and bivariate analyses: revision status, body mass index (BMI), duration of symptoms, preoperative NAHS, age at onset of symptoms, and need for acetabular microfracture. Positive predictors of 10-year survivorship included acute injury and gluteus medius repair, while negative predictors included revision arthroscopy, Tönnis grade, acetabular inclination, iliopsoas fractional lengthening, and notchplasty. CONCLUSION: Multiple predictive factors including age, BMI, revision status, and preoperative outcome scores were identified for long-term survivorship and functional outcomes. These may prove useful to clinicians in refining indications and guiding patients on expected outcomes of hip arthroscopy.

Mixed Reality Navigation in Hip Fusion Conversion: A Novel Utilization of Advanced Technology: A Case Report.

CASE: A 32-year-old woman with a history of hip fusion presented with significant lower back, hip, and knee pain as well as severely limited hip mobility and function. Single-stage fusion takedown and conversion to total hip arthroplasty (THA) was performed using augmented reality navigation. At 1 year, the patient was pain free with improved function. This study is the first to report the technique and outcomes of surgical fusion conversion to THA, using mixed reality navigation. CONCLUSION: Mixed reality navigation in complex conversion THA can be useful for identifying the patient's true acetabulum and for patient-specific acetabular component placement to maximize outcomes.

Exploring the clinical value of direct anterior approach THA for short-term hip function improvement: A single-center retrospective analysis of short-term outcomes.

To investigate the outcomes of the direct anterior approach (DAA) in total hip arthroplasty (THA) and its impact on improving hip joint function. This retrospective analysis included 94 patients who underwent THA between December 2017 and December 2020 at Dongguan Hospital, Guangzhou University of Chinese Medicine. The study group comprised 50 patients who received the DAA, while the control group comprised 44 patients who received the postero-lateral approach (PA). The follow-up period was 12 months. A comparison was made between the 2 groups based on perioperative indicators (operation time, intraoperative blood loss, hospitalization time, bed rest time, incision length, pain score), duration of walker use, incidence of postoperative complications, hip joint function (Harris score), quality of life (SF-36), and activities of daily living (ADL). The treatment effectiveness rate was higher in the study group (P < .05). The study group had a longer operation time, lower intraoperative blood loss, shorter hospitalization and bed rest time, smaller incision length, and lower visual analog scale (VAS) score after treatment, with statistically significant differences (P < .05). The study group also had a shorter duration of walker use after surgery (P < .05). The Harris score after treatment was higher in the study group compared to the control group (P < .05). Additionally, the study group had higher SF-36 scores and ADL scores after treatment (P < .05). There was no significant difference in the incidence of postoperative complications between the 2 groups (P > .05). The DAA in THA resulted in reduced pain and intraoperative blood loss, contributing to the promotion of postoperative recovery in patients with good short-term outcomes. This procedure warrants further promotion.

Total Hip Arthroplasty After Peri-Acetabular Osteotomy Results in Significant Improvement in Hip Function With Low Revision Rates at Mid-Term Follow-Up.

Background: Bernese periacetabular osteotomy (PAO) improves symptoms and delays degenerative changes in patients with acetabular dysplasia. Yet, eventual total hip arthroplasty (THA) is needed in many of these patients. The impact of PAO on subsequent THA outcomes is not well defined. The purpose of this study is to define: 1) clinical outcomes, 2) post-operative complications and 3) implant survivorship for patients undergoing THA after prior ipsilateral PAO. Methods: A retrospective review was conducted at three institutions to identify individuals undergoing THA after ipsilateral PAO surgery with minimum 1 year follow up. Patient reported outcome measures (PROMs) were collected preoperatively and at final follow-up. Surgical details, radiographic and clinical outcomes, and major complications according to the modified Dindo-Clavien classification system were identified through review of the medical record. Regression analysis and student's t-test were used to compare pre- and post-operative outcome scores. Kaplan-Meier analysis was performed to estimate reoperation-free survivorship. Results: A total of 113 THA in 112 patients were identified with initial review. 103 hips had a minimum of 1-year follow-up and an average follow of 5 ± 4 years (range, 1 to 20). 10 hips (9%) were lost to follow-up leaving 103 (91%) hips available for review with a minimum of 1-year follow-up (mean = 5 years). Mean interval from PAO to THA was 7.7 years (range, 2-15). The average post-operative mHHS improved 37 points (50 to 87, P < 0.001) when compared to pre-operative scores. Eight patients (7.1%) experienced a major grades III-V) surgical complication. These included 2 cases of instability, 2 cases of acetabular loosening, and one case each of periprosthetic fracture, wound dehiscence, periprosthetic infection, acetabular loosening and pneumonia. Failures occurred early at average 3.2 years and survivorship analysis for all-cause revision demonstrated 96% survivorship at both 5 and 10 years. Conclusion: THA after PAO achieves significant clinical improvement and satisfactory survivorship (96%) at mid-term follow-up, with a major complication rate of 7.1%. Level of Evidence: III.

Squatting biomechanics following physiotherapist-led care or hip arthroscopy for femoroacetabular impingement syndrome: a secondary analysis from a randomised controlled trial.

Background: Femoroacetabular impingement syndrome (FAIS) can cause hip pain and chondrolabral damage that may be managed non-operatively or surgically. Squatting motions require large degrees of hip flexion and underpin many daily and sporting tasks but may cause hip impingement and provoke pain. Differential effects of physiotherapist-led care and arthroscopy on biomechanics during squatting have not been examined previously. This study explored differences in 12-month changes in kinematics and moments during squatting between patients with FAIS treated with a physiotherapist-led intervention (Personalised Hip Therapy, PHT) and arthroscopy. Methods: A subsample (n = 36) of participants with FAIS enrolled in a multi-centre, pragmatic, two-arm superiority randomised controlled trial underwent three-dimensional motion analysis during squatting at baseline and 12-months following random allocation to PHT (n = 17) or arthroscopy (n = 19). Changes in time-series and peak trunk, pelvis, and hip biomechanics, and squat velocity and maximum depth were explored between treatment groups. Results: No significant differences in 12-month changes were detected between PHT and arthroscopy groups. Compared to baseline, the arthroscopy group squatted slower at follow-up (descent: mean difference -0.04 m∙s-1 (95%CI [-0.09 to 0.01]); ascent: -0.05 m∙s-1 [-0.11 to 0.01]%). No differences in squat depth were detected between or within groups. After adjusting for speed, trunk flexion was greater in both treatment groups at follow-up compared to baseline (descent: PHT 7.50° [-14.02 to -0.98]%; ascent: PHT 7.29° [-14.69 to 0.12]%, arthroscopy 16.32° [-32.95 to 0.30]%). Compared to baseline, both treatment groups exhibited reduced anterior pelvic tilt (descent: PHT 8.30° [0.21-16.39]%, arthroscopy -10.95° [-5.54 to 16.34]%; ascent: PHT -7.98° [-0.38 to 16.35]%, arthroscopy -10.82° [3.82-17.81]%), hip flexion (descent: PHT -11.86° [1.67-22.05]%, arthroscopy -16.78° [8.55-22.01]%; ascent: PHT -12.86° [1.30-24.42]%, arthroscopy -16.53° [6.72-26.35]%), and knee flexion (descent: PHT -6.62° [0.56- 12.67]%; ascent: PHT -8.24° [2.38-14.10]%, arthroscopy -8.00° [-0.02 to 16.03]%). Compared to baseline, the PHT group exhibited more plantarflexion during squat ascent at follow-up (-3.58° [-0.12 to 7.29]%). Compared to baseline, both groups exhibited lower external hip flexion moments at follow-up (descent: PHT -0.55 N∙m/BW∙HT[%] [0.05-1.05]%, arthroscopy -0.84 N∙m/BW∙HT[%] [0.06-1.61]%; ascent: PHT -0.464 N∙m/BW∙HT[%] [-0.002 to 0.93]%, arthroscopy -0.90 N∙m/BW∙HT[%] [0.13-1.67]%). Conclusion: Exploratory data suggest at 12-months follow-up, neither PHT or hip arthroscopy are superior at eliciting changes in trunk, pelvis, or lower-limb biomechanics. Both treatments may induce changes in kinematics and moments, however the implications of these changes are unknown. Trial registration details: Australia New Zealand Clinical Trials Registry reference: ACTRN12615001177549. Trial registered 2/11/2015.

A Prospective Randomized Controlled Trial Assessing the Impact of Preoperative Combined with Postoperative Progressive Resistance Training on Muscle Strength, Gait, Balance and Function in Patients Undergoing Total Hip Arthroplasty.

Purpose: The aim of this study is to investigate the effects of a preoperative combined with postoperative moderate-intensity progressive resistance training (PRT) of the operative side in patients with hip osteoarthritis (HOA) who are undergoing total hip arthroplasty (THA). The study seeks to evaluate the impact of this combined intervention on muscle strength, gait, balance, and hip joint function in a controlled, measurable, and objective manner. Additionally, the study aims to compare the outcomes of this combined intervention with those of preoperative or postoperative muscle strength training conducted in isolation. Methods: A total of 90 patients with HOA scheduled for unilateral primary THA were randomly assigned to three groups: Pre group (preoperative PRT), Post group (postoperative PRT), and Pre& Post group (preoperative combined with postoperative PRT) focusing on hip flexion, extension, adduction, and abduction of operated side. Muscle strength, gait parameters, balance, and hip function were assessed at specific time points during a 12-month follow-up period. Results: All three groups showed significant improvements in muscle strength, with the Pre& Post group demonstrating the most pronounced and sustained gains. Gait velocity and cadence were significantly improved in the Pre& Post group at 1-month and 3-month postoperative follow-ups compared to the other groups. Similarly, the Pre& Post group exhibited superior balance performance at 3-month and 12-month postoperative follow-ups. The Harris Hip Score also showed better outcomes in the Pre& Post group at all follow-up intervals. Conclusion: Preoperative combined with postoperative moderate-intensity PRT in HOA patients undergoing THA led to superior improvements in muscle strength, gait, balance, and hip joint function compared to preoperative or postoperative PRT alone. This intervention shows significant promise in optimizing postoperative rehabilitation and enhancing patient outcomes following THA.

Indirect Head of the Rectus Femoris Tendon as a Graft for Segmental Hip Labral Reconstruction: An Anatomic, Radiographical, and Biomechanical Study in Comparison With Iliotibial Labral Reconstruction.

BACKGROUND: The indirect head of the rectus femoris (IHRF) tendon has been used as an autograft for segmental labral reconstruction. However, the biomechanical properties and anatomic characteristics of the IHRF, as they relate to surgical applications, have yet to be investigated. PURPOSE: To (1) quantitatively and qualitatively describe the anatomy of IHRF and its relationship with surrounding arthroscopically relevant landmarks; (2) detail radiographic findings pertinent to IHRF; (3) biomechanically assess segmental labral reconstruction with IHRF, including restoration of the suction seal and contact pressures in comparison with iliotibial band (ITB) reconstruction; and (4) assess potential donor-site morbidity caused by graft harvesting. STUDY DESIGN: Descriptive laboratory study. METHODS: A cadaveric study was performed using 8 fresh-frozen human cadaveric full pelvises and 7 hemipelvises. Three-dimensional anatomic measurements were collected using a 3-dimensional coordinate digitizer. Radiographic analysis was accomplished by securing radiopaque markers of different sizes to the evaluated anatomic structures of the assigned hip.Suction seal and contact pressure testing were performed over 3 trials on 6 pelvises under 4 different testing conditions for each specimen: intact, labral tear, segmental labral reconstruction with ITB, and segmental labral reconstruction with IHRF. After IHRF tendon harvest, each full pelvis had both the intact and contralateral hip tested under tension along its anatomic direction to assess potential site morbidity, such as tendon failure or bony avulsion. RESULTS: The centroid and posterior apex of the indirect rectus femoris attachment are respectively located 10.3 ± 2.6 mm and 21.0 ± 6.5 mm posteriorly, 2.5 ± 7.8 mm and 0.7 ± 8.0 mm superiorly, and 5.0 ± 2.8 mm and 22.2 ± 4.4 mm laterally to the 12:30 labral position. Radiographically, the mean distance of the IHRF to the following landmarks was determined as follows: anterior inferior iliac spine (8.8 ± 2.5 mm), direct head of the rectus femoris (8.0 ± 3.9 mm), 12-o'clock labral position (14.1 ± 2.8 mm), and 3-o'clock labral position (36.5 ± 4.4 mm). During suction seal testing, both the ITB and the IHRF reconstruction groups had significantly lower peak loads and lower energy to peak loads compared with both intact and tear groups (P = .01 to .02 for all comparisons). There were no significant differences between the reconstruction groups for peak loads, energy, and displacement at peak load. In 60° of flexion, there were no differences in normalized contact pressure and contact area between ITB or IHRF reconstruction groups (P > .99). There were no significant differences between intact and harvested specimen groups in donor-site morbidity testing. CONCLUSION: The IHRF tendon is within close anatomic proximity to arthroscopic acetabular landmarks. In the cadaveric model, harvesting of the IHRF tendon as an autograft does not lead to significant donor-site morbidity in the remaining tendon. Segmental labral reconstruction performed with the IHRF tendon exhibits similar biomechanical outcomes compared with that performed with ITB. CLINICAL RELEVANCE: This study demonstrates the viability of segmental labral reconstruction with an IHRF tendon and provides a detailed anatomic description of the tendon in the context of an arthroscopic labral reconstruction. Clinicians can use this information during the selection of a graft and as a guide during an arthroscopic graft harvest.

Effect of Spinopelvic Parameters on Outcomes After Hip Arthroscopy for Femoroacetabular Impingement Syndrome.

BACKGROUND: Spinopelvic parameters, including pelvic tilt (PT), sacral slope (SS), and pelvic incidence, have been developed to characterize the relationship between lumbar spine and hip motion, but a paucity of literature is available characterizing differences in spinopelvic parameters among patients with femoroacetabular impingement syndrome (FAIS) versus patients without FAIS, as well as the effect of these parameters on outcomes of arthroscopic treatment of FAIS. PURPOSE: To (1) identify differences in spinopelvic parameters between patients with FAIS versus controls without FAIS; (2) identify associations between spinopelvic parameters and preoperative patient-reported outcomes (PROs); and (3) identify differences in PROs between patients with stiff spines (standing-sitting ΔSS ≤10°) versus those without. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: The study enrolled patients ≥18 years of age who underwent primary hip arthroscopy for treatment of FAIS with cam, pincer, or mixed (cam and pincer) morphology. Participants underwent preoperative standing-sitting imaging with a low-dose 3-dimensional radiography system and were matched on age and body mass index (BMI) to controls without FAIS who also underwent EOS imaging. Spinopelvic parameters measured on EOS films were compared between the FAIS and control groups. Patients with FAIS completed the modified Harris Hip Score (mHHS) and Non-Arthritic Hip Score (NAHS) before surgery and at 1-year follow-up. Outcome scores were compared between patients with stiff spines versus those without. Associations between spinopelvic parameters and baseline outcome scores were assessed with Pearson correlations. Continuous variables were compared with Student t test and/or Mann-Whitney U test, and categorical variables were compared with Fisher exact test. RESULTS: A total of 50 patients with FAIS (26 men; 24 women; mean age, 36.1 ± 10.7 years; mean BMI, 25.6 ± 4.2) were matched to 30 controls without FAIS (13 men; 17 women; mean age, 36.6 ± 9.5 years; mean BMI, 26.7 ± 3.6). Age, sex, and BMI were not significantly different between the FAIS and control groups (P > .05). Standing PT was not significantly different between stiff and non-stiff cohorts (P = .73), but sitting PT in the FAIS group was more than double that of the control group (36.5° vs 15.0°; P < .001). Incidence of stiff spine was significantly higher in the FAIS group (62.0% vs 3.3%; P < .001). Among FAIS patients, those with stiff spines had a significantly higher prevalence of cam impingement, whereas those with non-stiff spines had a higher prevalence of mixed impingement (P = .04). No significant differences were seen in preoperative mHHS or NAHS scores or pre- to postoperative improvement in scores between FAIS patients with stiff spines versus those without (P > .05), but a greater sitting SS was found to be positively correlated with a higher baseline mHHS (r = 0.36; P = .02). CONCLUSION: Patients with FAIS were more likely to have a stiff spine (standing-sitting ΔSS ≤10°) compared with control participants without FAIS. FAIS patients with stiff spines were more likely to have isolated cam morphology than patient without stiff spines. Although sitting SS was positively correlated with baseline mHHS, no significant differences were seen in 1-year postoperative outcomes between FAIS patients with versus without stiff spine.