Multicenter, prospective cohort study: immediate postoperative gains in active range of motion following robotic-assisted total knee replacement compared to a propensity-matched control using manual instrumentation.

BACKGROUND: Range of motion (ROM) following total knee replacement (TKR) has been associated with patient satisfaction and knee function, and is also an early indicator of a successful procedure. Robotic-assisted TKR (raTKR) is considered to reproduce more precise resections, and, as a result, may be associated with improved early patient satisfaction compared to manual TKR (mTKR). The purpose of this study was to evaluate the early postoperative active ROM (aROM) between raTKR and mTKR. METHODS: A total of 216 mTKR patients were propensity-matched, in terms of age, gender, comorbidities, and BMI, to 216 raTKR cases. Intraoperative and immediate postoperative adverse events were collected. Knee flexion and extension aROM were measured preoperatively and at one- and three months after operation. RESULTS: Changes in flexion aROM were significantly greater in raTKR vs. mTKR at one- (6.9°, 95% CI: 3.5, 10.4°) and three months (4.9°, 95% CI: 2.1, 7.7°). Flexion aROM was greater at three postoperative months compared to preoperative aROM only in the raTKR group, and raTKR patients had higher odds of achieving ≥ 90° of flexion at one month after operation (OR: 2.15, 95% CI: 1.16, 3.99). There were no significant differences between groups in intraoperative (P > 0.999) or postoperative adverse events. CONCLUSIONS: Compared with mTKR, raTKR resulted  in less loss of aROM immediately after operation and a faster recovery of aROM within three months after operation. TRIAL REGISTRATION: Clinicaltrials.gov (NCT# 03737149).

Stepping Beyond Counts in Recovery of Total Hip Arthroplasty: A Prospective Study on Passively Collected Gait Metrics.

Gait quality parameters have been used to measure recovery from total hip arthroplasty (THA) but are time-intensive and previously could only be performed in a lab. Smartphone sensor data and algorithmic advances presently allow for the passive collection of qualitative gait metrics. The purpose of this prospective study was to observe the recovery of physical function following THA by assessing passively collected pre- and post-operative gait quality metrics. This was a multicenter, prospective cohort study. From six weeks pre-operative through to a minimum 24 weeks post-operative, 612 patients used a digital care management application that collected gait metrics. Average weekly walking speed, step length, timing asymmetry, and double limb support percentage pre- and post-operative values were compared with a paired-sample t-test. Recovery was defined as the post-operative week when the respective gait metric was no longer statistically inferior to the pre-operative value. To control for multiple comparison error, significance was set at p < 0.002. Walking speeds and step length were lowest, and timing asymmetry and double support percentage were greatest at week two post-post-operative (p < 0.001). Walking speed (1.00 ± 0.14 m/s, p = 0.04), step length (0.58 ± 0.06 m/s, p = 0.02), asymmetry (14.5 ± 19.4%, p = 0.046), and double support percentage (31.6 ± 1.5%, p = 0.0089) recovered at 9, 8, 7, and 10 weeks post-operative, respectively. Walking speed, step length, asymmetry, and double support all recovered beyond pre-operative values at 13, 17, 10, and 18 weeks, respectively (p < 0.002). Functional recovery following THA can be measured via passively collected gait quality metrics using a digital care management platform. The data suggest that metrics of gait quality are most negatively affected two weeks post-operative; recovery to pre-operative levels occurs at approximately 10 weeks following primary THA, and follows a slower trajectory compared to previously reported step count recovery trajectories.

Which hip morphology measures and patient factors are associated with age of onset and symptom severity in femoroacetabular impingement syndrome?

BACKGROUND: Bony morphology is central to the pathomechanism of femoroacetabular impingement syndrome (FAIS), however isolated radiographic measures poorly predict symptom onset and severity. More comprehensive morphology measurement considered together with patient factors may better predict symptom presentation. This study aimed to determine the morphological parameter(s) and patient factor(s) associated with symptom age of onset and severity in FAIS. METHODS: 99 participants (age 32.9 ± 10.5 years; body mass index (BMI 24.3 ± 3.1 kg/m2; 42% females) diagnosed with FAIS received standardised plain radiographs and magnetic resonance scans. Alpha angle in four radial planes (superior to anterior), acetabular version (AV), femoral torsion, lateral centre-edge, anterior centre-edge (ACEA) and femoral neck-shaft angles were measured. Age of symptom onset (age at presentation minus duration of symptoms), international Hip Outcome Tool-33 (iHOT-33) and modified UCLA activity scores were recorded. Backward stepwise regression assessed morphological parameters and patient factors (age, sex, BMI, symptom duration, annual income, private/public healthcare system accessed) to determine variables independently associated with onset age and iHOT-33 score. RESULTS: Earlier symptom onset was associated with larger superoanterior alpha angle (p = 0.007), smaller AV (p = 0.023), lower BMI (p = 0.010) and public healthcare system access (p = 0.041) (r2 = 0.320). Worse iHOT-33 score was associated with smaller ACEA (p = 0.034), female sex (p = 0.040), worse modified UCLA activity score (p = 0.010) and public healthcare system access (p < 0.001) (r2 = 0.340). CONCLUSIONS: Age of symptom onset was chiefly predicted by femoral and acetabular bony morphology measures, whereas symptom severity predominantly by patient factors. Factors measured explained a small amount of variance in the data; additional unmeasured factors may be more influential.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial.

BACKGROUND: Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life. PURPOSE: To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change. RESULTS: A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (ß = -0.82; P = .034), access to private health care (ß = 12.91; P = .013), and worse baseline iHOT-33 score (ß = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (ß = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively). CONCLUSION: No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.

Hip Contact Force Magnitude and Regional Loading Patterns Are Altered in Those with Femoroacetabular Impingement Syndrome.

PURPOSE: The magnitude and location of hip contact force influence the local mechanical environment of the articular tissue, driving remodeling. We used a neuromusculoskeletal model to investigate hip contact force magnitudes and their regional loading patterns on the articular surfaces in those with femoroacetabular impingement (FAI) syndrome and controls during walking. METHODS: An EMG-assisted neuromusculoskeletal model was used to estimate hip contact forces in eligible participants with FAI syndrome ( n = 41) and controls ( n = 24), walking at self-selected speed. Hip contact forces were used to determine the average and spread of regional loading for femoral and acetabular articular surfaces. Hip contact force magnitude and region of loading were compared between groups using statistical parametric mapping and independent t -tests, respectively ( P < 0.05). RESULTS: All of the following findings are reported compared with controls. Those with FAI syndrome walked with lower-magnitude hip contact forces (mean difference, -0.7 N·BW -1 ; P < 0.001) during first and second halves of stance, and with lower anteroposterior, vertical, and mediolateral contact force vector components. Participants with FAI syndrome also had less between-participant variation in average regional loading, which was located more anteriorly (3.8°, P = 0.035) and laterally (2.2°, P = 0.01) on the acetabulum but more posteriorly (-4.8°, P = 0.01) on the femoral head. Participants with FAI syndrome had a smaller spread of regional loading across both the acetabulum (-1.9 mm, P = 0.049) and femoral head (1 mm, P < 0.001) during stance. CONCLUSIONS: Compared with controls, participants with FAI syndrome walked with lower-magnitude hip contact forces that were constrained to smaller regions on the acetabulum and femoral head. Differences in regional loading patterns might contribute to the mechanobiological processes driving cartilage maladaptation in those with FAI syndrome.

Similar kinematic patterns between revision total stabilized (TS) and primary posterior stabilized (PS) knee prostheses: a prospective case-controlled study with gait assessment.

PURPOSE: There are increased surgical considerations when revising total knee arthroplasty (TKA) in active patients. Few studies have assessed if a semi-constrained [Total Stabilized (TS)] prostheses has similar knee biomechanics to a primary posterior stabilized (PS) prosthesis. The aim was to compare the gait parameters in patients with PS or TS TKA and normal controls. METHODS: 32 patients with TKA were prospectively included with either a primary PS (n = 15) or a revision TS (n = 17) prosthesis. Gait analysis was performed at 6 months postoperatively for each patient, with an optoelectronic knee assessment device (KneeKG®) assessing the displacement of the tibia relative to the femur during the different gait phases (flexion/extension, anterior/posterior translation, adduction/abduction, internal/external rotation). A control group (n = 12) of healthy knees was compared with the TKA groups. RESULTS: There were no significant kinematic differences between PS and TS groups. The maximum knee flexion during gait was 53° ± 8.1° in the PS group vs 52° ± 8.7° in the TS group. The antero-posterior translation was similar in both group (2.3 ± 0.5 mm vs 2.6 ± 0.9 mm, respectively). Peak varus angle during loading and swing phase was slightly higher in the TS group (2.7° ± 0.7° and 5.2° ± 0.9°) than in the PS group (2.9° ± 0.6° and 5.6° ± 1.2°), without significant difference. The ranges in internal/external rotation were similar between PS and TS TKA (3.7° ± 0.5° vs 3.3° ± 0.6°, respectively). Both designs approached closely the normal gait patterns of the control group except in the frontal plane. CONCLUSION: Single radius TS TKA has gait parameters similar to single radius PS TKA. Use of a single radius TS TKA in revision TKA is not detrimental to a patient's gait pattern. Both designs approached closely the normal gait patterns of the control group. LEVEL OF EVIDENCE: Prospective, case-control study; Level III.

Reproducibility of an Intraoperative Pressure Sensor in Total Knee Replacement.

Appropriate soft tissue tension in total knee replacement (TKR) is an important factor for a successful outcome. The purpose of our study was to assess both the reproducibility of a modern intraoperative pressure sensor (IOP) and if a surgeon could unconsciously influence measurement. A consecutive series of 80 TKRs were assessed with an IOP between January 2018 and December 2020. In the first scenario, two blinded sequential measurements in 48 patients were taken; in a second scenario, an initial blinded measurement and a subsequent unblinded measurement in 32 patients were taken while looking at the sensor monitor screen. Reproducibility was assessed by intraclass correlation coefficients (ICCs). In the first scenario, the ICC ranged from 0.83 to 0.90, and in the second scenario it ranged from 0.80 to 0.90. All ICCs were 0.80 or higher, indicating reproducibility using a IOP and that a surgeon may not unconsciously influence the measurement. The use of a modern IOP to measure soft tissue tension in TKRs is a reproducible technique. A surgeon observing the measurements while performing IOP may not significantly influence the result. An IOP gives additional information that the surgeon can use to optimize outcomes in TKR.

Multi-centre randomised controlled trial comparing arthroscopic hip surgery to physiotherapist-led care for femoroacetabular impingement (FAI) syndrome on hip cartilage metabolism: the Australian FASHIoN trial.

BACKGROUND: Arthroscopic surgery for femoroacetabular impingement syndrome (FAI) is known to lead to self-reported symptom improvement. In the context of surgical interventions with known contextual effects and no true sham comparator trials, it is important to ascertain outcomes that are less susceptible to placebo effects. The primary aim of this trial was to determine if study participants with FAI who have hip arthroscopy demonstrate greater improvements in delayed gadolinium-enhanced magnetic resonance imaging (MRI) of cartilage (dGEMRIC) index between baseline and 12 months, compared to participants who undergo physiotherapist-led management. METHODS: Multi-centre, pragmatic, two-arm superiority randomised controlled trial comparing physiotherapist-led management to hip arthroscopy for FAI. FAI participants were recruited from participating orthopaedic surgeons clinics, and randomly allocated to receive either physiotherapist-led conservative care or surgery. The surgical intervention was arthroscopic FAI surgery. The physiotherapist-led conservative management was an individualised physiotherapy program, named Personalised Hip Therapy (PHT). The primary outcome measure was change in dGEMRIC score between baseline and 12 months. Secondary outcomes included a range of patient-reported outcomes and structural measures relevant to FAI pathoanatomy and hip osteoarthritis development. Interventions were compared by intention-to-treat analysis. RESULTS: Ninety-nine participants were recruited, of mean age 33 years and 58% male. Primary outcome data were available for 53 participants (27 in surgical group, 26 in PHT). The adjusted group difference in change at 12 months in dGEMRIC was -59 ms (95%CI - 137.9 to - 19.6) (p = 0.14) favouring PHT. Hip-related quality of life (iHOT-33) showed improvements in both groups with the adjusted between-group difference at 12 months showing a statistically and clinically important improvement in arthroscopy of 14 units (95% CI 5.6 to 23.9) (p = 0.003). CONCLUSION: The primary outcome of dGEMRIC showed no statistically significant difference between PHT and arthroscopic hip surgery at 12 months of follow-up. Patients treated with surgery reported greater benefits in symptoms at 12 months compared to PHT, but these benefits are not explained by better hip cartilage metabolism. TRIAL REGISTRATION DETAILS: Australia New Zealand Clinical Trials Registry reference: ACTRN12615001177549 . Trial registered 2/11/2015.

Is It Safe to Use a Lead Screen During Hip Arthroscopy?

PURPOSE: To assess the radiation attenuation of lead screens in comparison to lead gowns in a simulated hip arthroscopy setting. METHODS: In this quantitative laboratory study, a phantom pelvis was used to simulate the scatter produced by patients during hip arthroscopy. Radiation measurements were taken using a handheld radiation detector positioned perpendicular to the phantom pelvis at 1.5 m and 2 m. Measurements were taken without shielding as a control, behind a lead gown (0.4-mm lead equivalent), and behind a lead screen (0.5-mm lead equivalent). RESULTS: With the detector at 1.5 m perpendicular to the hip, equivalent radiation was attenuated by the lead screen (94%) and the lead gown (94%). With the detector at 2 m perpendicular to the hip, the lead screen at 1.7 m attenuated 95% of radiation. CONCLUSIONS: In hip arthroscopy, using lead screens is a safe and more comfortable alternative to wearing lead gowns. The lead screen should be at least 1.2 m from the radiation source, with the surgeon standing closely behind the screen, fully covered. CLINICAL RELEVANCE: Lead screens can be safely used in hip arthroscopy.

Posterior-Stabilized TKA in Patients With Severe Genu Recurvatum Achieves Good Clinical and Radiological Results at 5-year Minimum Follow-Up: A Case-Controlled Study.

BACKGROUND: Genu recurvatum is a rare knee deformity. Total knee arthroplasty (TKA) in severe preoperative recurvatum requires surgical adjustments. Few studies have assessed the clinical and radiological results of TKA in recurvatum. The aim was to compare the clinical and radiological outcomes, complications, and revision rates after posterior-stabilized TKA in severe recurvatum with those without recurvatum. METHODS: Between 1987 and 2015, 32 primary posterior-stabilized TKA were performed with a preoperative genu recurvatum greater than 10° and minimum follow-up of 60 months. In severe genu recurvatum, the extension gap needs to be decreased compared with flexion gap. To achieve this, the distal femoral cut is distalized, whereas the posterior femoral and tibial cuts are performed as usual. They were compared with 64 matched posterior-stabilized TKAs without recurvatum. The demographic data were similar between groups. The clinical and radiological outcomes, complications, and revision rates were assessed at the last follow-up. RESULTS: At a mean follow-up of 7.4 years ± 1.9, there was no significant difference in International Knee Score functional score (77.5 vs. 73.4; P = .50) and knee score (86.6 vs. 89.5; P = .37) between the recurvatum group and the control group, respectively. 6 patients had a postoperative recurvatum equal or superior to 10° in the recurvatum group (18.8%). There was no difference between both groups in radiological outcomes, complication, or revision rates. No instability was found in the recurvatum group. CONCLUSION: Posterior-stabilized TKA with controlled distalization of the femoral component in the setting of severe preoperative genu recurvatum achieves good clinical and radiological outcomes at a minimum follow-up of 5 years and similar to TKA without preoperative recurvatum. LEVEL OF EVIDENCE: III.

Personalized alignment in total knee arthroplasty: current concepts.

Traditionally in total knee arthroplasty (TKA), a post-operative neutral alignment was the gold standard. This principle has been contested as functional outcomes were found to be inconsistent. Analysis of limb alignment in the non-osteoarthritic population reveals variations from neutral alignment and consideration of a personalized or patient-specific alignment in TKA is challenging previous concepts. The aim of this review was to clarify the variations of current personalized alignments and to report their results. Current personalized approaches of alignment reported are: kinematic, inverse kinematic, restricted kinematic, and functional. The principle of "kinematic alignment" is knee resurfacing with restitution of pre-arthritic anatomy. The aim is to resurface the femur maintaining the native femoral joint line obliquity. The flexion and extension gaps are balanced with the tibial resection. The principle of the "inverse kinematic alignment" is to resurface the tibia with similar medial and lateral bone resections in order to keep the native tibial joint line obliquity. Gap balancing is performed by adjusting the femoral resections. To avoid reproducing extreme anatomical alignments there is "restricted kinematic alignment" which is a compromise between mechanical alignment and true kinematic alignment with a defined safe zone of alignment. Finally, there is the concept of "functional alignment" which is an evolution of kinematic alignment as enabling technology has progressed. This is obtained by manipulating alignment, bone resections, soft tissue releases, and/or implant positioning with a robotic-assisted system to optimize TKA function for a patient's specific alignment, bone morphology, and soft tissue envelope. The aim of personalizing alignment is to restore native knee kinematics and improve functional outcomes after TKA. A long-term follow-up remains crucial to assess both outcomes and implant survivorship of these current concepts.

Trunk, pelvis and lower limb walking biomechanics are similarly altered in those with femoroacetabular impingement syndrome regardless of cam morphology size.

BACKGROUND: Studies of walking in those with femoroacetabular impingement syndrome have found altered pelvis and hip biomechanics. But a whole body, time-contiuous, assessment of biomechanical parameters has not been reported. Additionally, larger cam morphology has been associated with more pain, faster progression to end-stage osteoarthritis and increased cartilage damage but differences in walking biomechanics between large compared to small cam morphologies have not been assessed. RESEARCH QUESTION: Are trunk, pelvis and lower limb biomechanics different between healthy pain-free controls and individuals with FAI syndrome and are those biomechanics different between those with larger, compared to smaller, cam morphologies? METHODS: Twenty four pain-free controls were compared against 41 participants with FAI syndrome who were stratified into two groups according to their maximum alpha angle. Participants underwent three-dimensional motion capture during walking. Trunk, pelvis, and lower limb biomechanics were compared between groups using statistical parametric mapping corrected for walking speed and pain. RESULTS: Compared to pain-free controls, participants with FAI syndrome walked with more trunk anterior tilt (mean difference 7.6°, p < 0.001) as well as less pelvic rise (3°, p < 0.001), hip abduction (-4.6°, p < 0.05) and external rotation (-6.5°, p < 0.05). They also had lower hip flexion (-0.06Nm⋅kg-1, p < 0.05), abduction (-0.07Nm⋅kg-1, p < 0.05) and ankle plantarflexion moments (-0.19Nm⋅kg-1, p < 0.001). These biomechanical differences occurred throughout the gait cycle. There were no differences in walking biomechanics according to cam morphology size. SIGNIFICANCE: Results do not support the hypothesis that larger cam morphology is associated with larger differences in walking biomechanics but did demonstrate general differences in trunk, pelvis and lower limb biomechanics between those with FAI sydrome and pain-free controls. Altered external biomechanics are likely the result of complex sensory-motor strategy resulting from pain inhibition or impingement avoidance. Future studies should examine internal loading in those with FAI sydnrome.

Early low complication rate of ceramic-on-ceramic total hip arthroplasty by direct anterior approach.

INTRODUCTION: Ceramic-on-ceramic couplings are an alternative bearing surface to reduce the problems related to polyethylene wear and debris. However, ceramic articulations have their own risk of unique complications: fracture, squeaking, or dislocation. Few studies have assessed the outcomes of ceramic-on-ceramic total hip arthroplasties (THA) by direct anterior approach (DAA). The aim was to evaluate the early complications and revision rate of ceramic-on-ceramic THA by DAA. MATERIAL: A retrospective single-center study of 116 consecutive THAs was performed by DAA (106 patients) with ceramic-on-ceramic bearing from January 2015 to February 2018 with a minimum 24 months of follow-up. No patients were lost to follow-up. The mean age was of 55.3 years ± 11.3. The same cementless acetabular shell with a Biolox Delta ceramic insert and head were used. The complication and revision rates were collected at the last follow-up. The positioning of the acetabular implant was assessed on standard radiographs. Postoperative clinical outcomes were assessed by the Harris Hip Score. RESULTS: At a mean follow-up of 31.9 months ± 5.5, no THA was revised. Five patients had late complications: 3 squeaking (2.6%) and 2 psoas impingements (1.7%) and were managed conservatively. All patients had satisfactory bony ingrowth of acetabular component, with no radiolucent lines and no osteolysis. Eight patients (6.9%) had an anterior overhang of the cup. The mean overhang for these patients was 4.1 mm. 111 hips (96%) were perceived as forgotten or having no limitations. CONCLUSION: This ceramic-on-ceramic coupling and shell by DAA produced excellent clinical outcomes and implant survival rate at a minimum two-year follow-up study. No serious complication was observed during the follow-up.

High Midterm Survival Rate of Uncemented Total Knee Arthroplasty After High Tibial Osteotomy: A Case-Control Study.

BACKGROUND: Total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is technically more demanding than TKA in a native knee. Studies have reported increased intraoperative and postoperative complication of TKA with previous HTO. The aim of this study is to compare the survival and complication rates and functional outcomes of uncemented TKA with previous HTO to primary TKA at our institution over a decade. METHODS: This case-control study included 41 uncemented TKA after HTO between 2002 and 2012. For each case, 2 control patients were matched based on age and gender without previous HTO. The 2 groups were comparable for body mass index, as well as preoperative functional scores. RESULTS: The mean follow-up was 7.8 ± 2.4 (range, 5-13.6) years. At last follow-up, there was no significant difference in functional outcomes or radiological imaging, particularly the rate of radiological loosening. There was no significant difference in complications (9; 22%) in the group of TKA after HTO vs the control group (14; 17%). One revision was performed in the group of TKA after HTO for septic loosening, and no revisions in the control group. The survival rate at a mean follow-up of 8 years was 97.6% in the group TKA after HTO vs 100% in the control group. CONCLUSION: Uncemented TKAs following HTO have no significant difference in functional and radiological outcomes and survivorship compared to uncemented primary TKA at midterm follow-up.

Dual Mobility Cups in Revision Total Hip Arthroplasty: Efficient Strategy to Decrease Dislocation Risk.

BACKGROUND: Revision total hip arthroplasty (rTHA) is a challenging surgery with a higher rate of complications than primary arthroplasty, particularly instability and aseptic loosening. The purpose of this study is to compare dual mobility cup (DMC) and standard mobility cup (SMC) in all rTHAs performed at our institution over a decade with a 1 year minimum follow-up. METHODS: Two hundred ninety-five rTHAs (acetabular only and bipolar revisions) between 2006 and 2016 were retrospectively reviewed. These were divided into those with a DMC (184 revisions) or SMC (111 revisions). Dislocation and complications requiring re-revision were reported. RESULTS: The rTHA mean age was 69 years ± 13.9 (19-92) and the mean follow-up was 2.3 years. Dislocation risk was statistically lower (P = .01) with a DMC (3.8%; 7/184) than with an SMC (13.5%; 15/111). DMC required re-rTHA in 24/184 (13%) for any reason compared to SMC in 19/111 (17.1%) (P = .34). There was no significant difference in early aseptic loosening (P = .28) between the 2 groups. For young patients (≤55 years), results were similar with a lower dislocation rate in the DMC group (P = .24) and no increased risk of early aseptic loosening (P = .49). CONCLUSION: This study demonstrates that for all rTHA indications DMC compared to SMC has a significantly decreased risk of postoperative dislocation without risk of early aseptic loosening at medium term follow-up. The use of DMC in rTHA is an important consideration particularly with the predicted increased incidence of both primary and revision THA globally.

The outcome of arthroscopic repair of acetabular labral tears using the iHOT-33.

BACKGROUND: The purpose of this study was to determine patient reported outcome measures (PROMS) after arthroscopic repair of an isolated labral tear using the validated International Hip Outcome Tool (iHOT-33). The iHOT-33 specifically measures (1) symptoms and functional limitations, (2) sport and recreation limitations, (3) job related concerns and social and (4) emotional and lifestyle concerns. METHODS: A retrospective review was performed on 45 procedures in 43 patients between September 2012 and September 2015. Two patients had bilateral isolated labral tears. Patients were excluded if they were younger than 18 years, had prior ipsilateral hip surgery and had radiological or arthroscopic evidence of femoroacetabular impingement (FAI), hip dysplasia or other bony dysmorphism. RESULTS: Of the 43 patients undergoing arthroscopy there were 29 right and 16 left hips repaired. There were 34 females and 9 males. The mean age at surgery was 37.4 years (range 19-63 years) with a mean follow up of 1.7 years (range 1.0-2.6 years). At follow up the mean total iHOT-33 score improved from 34.1 to 67.3 (p < 0.02). The mean improvement was 33.2 (p = < 0.02). Significant improvements were described in all 4 iHOT-33 sub sections. CONCLUSION: The study showed statistically significant favourable outcomes in selected patients with short follow-up for patients that underwent hip arthroscopy for an isolated labral tear using the validated iHOT-33. LEVEL OF EVIDENCE: IV, retrospective non-randomised study.

Prevalence and Trends of Patient-Reported Outcome Measures Used in Hip Arthroscopy.

The aim of this review was to determine the prevalence of patient-reported outcome measures concerning outcomes of arthroscopic hip surgery. The PubMed database was comprehensively reviewed in March 2016 using the key terms "hip" and "arthroscopy." A total of 192 eligible studies were identified. The most commonly used patient-reported outcome measures were the modified Harris Hip score (61%) and the Non-arthritic Hip Score (27%). Seventy-one percent of total patient-reported outcome measures articles were published between 2011 and 2015. The modified Harris Hip score, Nonarthritic Hip Score, and Hip Outcome Score remain the most commonly used patient-reported outcome measures in studies concerning outcomes of hip arthroscopy, and this has increased in the past 5 years. [Orthopedics. 2019; 42(3):e305-e308.].

The effect of surgical approach on early complications of total hip arthroplasty.

BACKGROUND: Total hip arthroplasty (THA) is traditionally associated with a low complication rate, with complications such as infection, fracture and dislocation requiring readmission or reoperation. We seek to identify the complication rate among the anterior, direct lateral and posterior surgical approaches. METHODS: We reviewed all THAs performed at the Epworth Healthcare from 1 July 2014 to 30 June 2016. There were 2437 THAs performed by a variety of approaches. No hips were excluded from this study. We surveyed the hospital database and the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR) to identify those patients who had been readmitted and/or reoperated on. Details collected included age, gender, laterality of the surgery (left/right/bilateral), surgical approach utilised, complications which occurred. RESULTS: There were 29 peri-prosthetic fractures detected (13 anterior, 9 lateral, 7 posterior) and 10 underwent revision of implant, 19 were fixed. The increased rate of revision in the anterior group was statistically significant. There were 14 dislocations (5 anterior, 1 lateral, 8 posterior) of which 8 prostheses were revised. Three cases operated via the anterior approach and 1 by the lateral had early subsidence without fracture, necessitating revision of the femoral prostheses. Operative site infection occurred in 12 cases (2 anterior, 4 lateral, 6 posterior) with 6 requiring revision of implants. CONCLUSION: The complication rates between the 3 main approaches are similar, but individual surgeons should be vigilant for complications unique to their surgical approaches, such as femoral fractures in the anterior approach and dislocations in the posterior approach.

Influence of femoral broach shape on stem alignment using anterior approach for total hip arthroplasty: A radiologic comparative study of 3 different stems.

BACKGROUND: Malalignment of the femoral stem in total hip arthroplasty (THA) can detrimentally affect outcome. Poor preparation of the femur intraoperatively is an important cause of stem malalignment. PURPOSES: The objective was to compare coronal alignment of three different stems using three different broaches. METHODS: Retrospective study of three groups of 60 patients following primary THA via direct anterior approach, by the same surgeon, between January 2015 and January 2016. Each group had a similar designed stem (Corail Depuy, Targos Lepine or Meije Tornier). Groups were matched for age, body mass index, gender, side, neck shaft angle and indications. The significant difference between groups was the broach shape. Broaches for the Corail and Meije stems had a prominent shoulder laterally, while the broach of the Targos stem had a rounded less prominent shape laterally. Coronal alignment was determined radiologically at 2 months. RESULTS: The mean varus was significantly lower for the Targos stems (1.1° +/-0.8) compared to the Corail (2.3° +/-1.5) and Meije stems (1.9° +/-1.2) (p<0.0001). There were significantly less Targos stems with varus greater than 3° (1.7%, n = 1) compared to the Corail (40%, n = 24) and Meije stems (20%, n = 12) (p<0.001). CONCLUSION: A femoral broach with a prominent lateral shoulder when performing a THA via direct anterior approach will increase the risk of varus femoral stem alignment compared to a less laterally prominent broach.

Outcomes of arthroscopic debridement of isolated Ligamentum Teres tears using the iHOT-33.

BACKGROUND: Tears of the Ligamentum Teres are a common cause of groin pain. Tears of the ligament frequently co-exist alongside other bony or labral intra-articular hip lesions, which are also treated at the time of arthroscopy. For this reason, it is often difficult to assess the effect that debridement alone has on improving patient pain and function. This study aims to assess the short-term outcomes of arthroscopic debridement of isolated Ligamentum Teres tears using a validated patient-reported outcome score - the International Hip Outcome Tool (iHOT-33). METHODS: A retrospective review was performed of 35 patients (37 hips) who had an isolated Ligamentum Teres tear treated with arthroscopic radiofrequency debridement between September 2012 and September 2015. Patients with concomitant intra-articular hip pathology (femoroacetabular impingement, labral lesions, hip dysplasia) were excluded from the study. All patients completed the iHOT-33 questionnaire pre-operatively and post-operatively. The mean age was 37.7 years (range 16-67 years) and patients were followed up for a mean period of 17.7 months (range 6-42 months). Thirty-one patients were female and 4 were male. RESULTS: Thirty-seven isolated partial tears were managed with arthroscopic radiofrequency debridement. At follow up, the mean iHOT-33 score improved from 26.9 pre-operatively to 48.0 post-operatively, representing a mean improvement of 21.1 (p < 0.001). The minimum clinically important difference of the iHOT-33 is 6.1 points. Significant improvements were noted in all four sub-sections of the iHOT-33. CONCLUSION: Arthroscopic radiofrequency debridement of isolated Ligamentum Teres tears provides short-term benefit in the majority of patients, including significant improvement in sporting function.