Retroperitoneal and lower extremities muscle bleeding in acquired haemophilia A (AHA): Risk factors and implications in disability and survival.

AIM: To assess risk factors of retroperitoneal and lower extremity musculoskeletal bleed in acquired haemophilia (AHA) and perform an objective assessment of disability and influence on survival. METHODS: We included 49 patients with AHA from November 2017 to May 2023. The occurrence of any retroperitoneal or/and lower extremities bleeding manifestation was investigated. On clinical follow-up, we search for compressive femoral neuropathy and quadriceps amyotrophy. The lower extremity functional scale (LEFS) was carried out one year after the last bleeding event in all AHA patients. RESULTS: A 61.2% of patients in our AHA cohort presented with any retroperitoneal and/or lower extremities musculoskeletal manifestation. Those patients had higher percentage of major bleeding EACH2/ISTH criteria (90% vs. 57%, p = .01), needs of blood transfusions (86% vs. 57% of patients, p = .03), and haemostatic by-pass products (90% vs. 63%, p = .02). Hypertension (HR 2.6, 95% CI 1.1-5.9, p = .02), presence of autoimmune disease (HR 13, 95% CI 1.7-99, p = .01), and inhibitor level > 20 BU (HR 2.6 95% CI 1.0-6.8, p = .04) significantly predicted retroperitoneal/lower extremities clinical manifestations. Most frequent sequelae were quad atrophy (30.6%) and femoral nerve palsy (20.4%). Quad atrophy and LEFS scores under 50 were associated with increased mortality (HR 3, 95% CI 1.1-8.6 and HR 12, 95% CI 3.3-45, respectively). CONCLUSION: AHA with retroperitoneal/lower extremities bleeding involvement is of greater severity and shows high disability and worst survival outcomes. Quadriceps atrophy and LEFS scale scoring under 50 predicted mortality in our AHA patients.

A simple scoring algorithm predicting paravertebral and/or iliopsoas abscess among adults with community-onset bloodstream infections: matters of PVL-producing Staphylococcus aureus.

PURPOSE: Misdiagnosis or delayed diagnosis of paravertebral and/or iliopsoas abscess (PVIPA) has been frequently reported to be associated with unfavorable prognosis. We aimed to develop a scoring algorithm that can easily and accurately identify patients at greater risk for PVIPA among individuals with community-onset bloodstream infections. METHODS: In a multicenter, retrospective cohort study, the score was developed with the first four study years and validated with the remaining two years. Applying logistic regression, the score values of prediction determinants were derived from the adjusted odds ratios (AOR). The performance of the scoring algorithm was assessed with the receiver operating characteristic (ROC) curve. RESULTS: In the derivation (3869 patients) and validation (1608) cohorts, patients with PVIPA accounted for 1.7% and 1.4%, respectively. In the derivation cohort, five independent predictors of PVIPA were recognized using multivariable analyses: time-to-defervescence > 5 days (AOR, 7.00; 2 points), Panton-Valentine Leukocidin (PVL)-producing Staphylococcus aureus (AOR, 5.98; 2 points), intravenous drug users (AOR, 2.60; 1 points), and comorbid hemato-oncology (AOR, 0.41; -1 point) or liver cirrhosis (AOR, 2.56; 1 points). In the derivation and validation cohorts, areas under ROC curves (95% confidence intervals) of the prediction algorithm are 0.83 (0.77-0.88) and 0.85 (0.80-0.90), and a cutoff score of + 2 represents sensitivity of 83.3% and 95.7%, specificity of 68.6% and 67.7%, positive predictive values of 4.4% and 4.1%, and negative predictive values of 99.6% and 99.9%, respectively. CONCLUSIONS: Of a scoring algorithm with substantial sensitivity and specificity in predicting PVIPA, PVL-producing S. aureus and Time-to-defervescence > 5 days were crucial determinants.

Satisfactory mid-term clinical outcomes of endoscopic tenotomy for iliopsoas tendinopathy following total hip arthroplasty.

PURPOSE: To report 5-year outcomes of endoscopic iliopsoas tenotomy in patients with iliopsoas tendinopathy following total hip arthroplasty (THA) and determine whether clinical scores are associated with cup position. METHODS: Patients who underwent endoscopic iliopsoas tenotomy for iliopsoas tendinopathy following THA (2014-2017) were contacted. Indications for endoscopic iliopsoas tenotomy after THA were groin pain during active hip flexion, exclusion of other causes of groin pain, and no pain relief after 6 months of conservative treatment. Pretenotomy cup inclination and anteversion were measured on radiographs; axial and sagittal cup overhang were measured on computed tomography (CT) scans. Oxford hip score (OHS), modified Harris hip score (mHHS), and groin pain were assessed. RESULTS: The initial cohort comprised 16 men (17 hips) and 31 women (32 hips), aged 60.7 ± 10.6 years. Cup inclination and anteversion were, respectively, 46.2 ± 6.2° and 14.6 ± 8.4°, while axial and sagittal cup overhang were, respectively, 4.4 ± 4.0 mm and 6.9 ± 4.5 mm. At ≥5 years follow-up, four hips underwent cup and stem revision, two underwent isolated cup revision and one underwent secondary iliopsoas tenotomy. OHS improved by 23 ± 10 and mHHS improved by 31 ± 16. Posttenotomy groin pain was slight in 20.0%, mild in 17.5% and moderate in 12.5%. Regression analyses revealed that net change in mHHS decreased with sagittal cup overhang (ß = -3.1; 95% confidence interval [CI] = -4.6 to -1.7; p < 0.001), but that there were no associations between cup position and net change in OHS. CONCLUSIONS: Endoscopic iliopsoas tenotomy provides good mid-term clinical outcomes in patients with iliopsoas tendinopathy following THA. Furthermore, improvements in mHHS were found to decrease with increasing sagittal cup overhang, in cases for which adequate preoperative imaging was available. LEVEL OF EVIDENCE: Level IV.

Assessment of function and muscle strength after endoscopic iliopsoas tenotomy to treat iliopsoas impingement after total hip arthroplasty.

PURPOSE: The objective of this study was to evaluate the functional outcome during follow-up (FU) after endoscopic tenotomy for iliopsoas (IP)-cup impingement and to quantitatively analyze the hip flexion strength. METHODS: This was a monocentric, retrospective cohort study of a single surgeon series. Functional assessment was based on the modified Harris score, the Oxford score and the visual analog scale score. Strength was measured with a handheld dynamometer in the sitting and lying position. RESULTS: Thirty-six IP tenotomies for cup impingement were performed between May 2013 and November 2021. Seven (19%) patients were lost to FU. At the time of tenotomy, the mean (standard deviation) age was 62,6 (12,2) and BMI was 26,5 (4,1). The mean FU time after tenotomy to the last FU was 3,6 (0,8) years. All three outcome scores improved from preoperatively to six months postoperatively (p < 0.001). There were no significant change from six months to last FU. The minimal clinically important difference (MCID) of the modified Harris score was set at 25. 20 (69%) patients had values that exceeded the threshold at one month and six months and neutral 19 (65.5%) had values that exceeded the threshold at the last FU. The limp symmetry index concerning hip flexion strength was 63% at 90° and 40% at 30° at the last FU. CONCLUSION: Most patients significantly improved their outcome scores after endoscopic iliopsoas tenotomy, with results remaining consistently stable over time. Despite a significant loss in hip flexion strength, the majority of patients did not report any impairment of their quality of life. STUDY DESIGN: Level III, Retrospective cohort study.

Anatomy of the iliopsoas notch and its relationship with morphology of the proximal femur.

PURPOSE: Discrepancy between the morphology of the acetabular margin and the design of hemispheric acetabular cups used in total hip arthroplasty may produce postoperative hip pain due to an iliopsoas impingement at the iliopsoas notch. This study aimed to determine the anatomical features of the iliopsoas notch in the Central European sample, and to test whether the morphology of the proximal femur affects the size of the iliopsoas notch. METHODS: The sample was composed of 40 matched pairs of dry hip bones and corresponding femora. The depth and length of the iliopsoas notch were measured and correlated with the available demographic data. The anthropometric parameters of the proximal femur were calculated using image-analysis software, and their association with the measurements of the iliopsoas notch was tested. RESULTS: The iliopsoas notch was present in all specimens and featured four morphological configurations: curved (61.3%), angular (16.2%), irregular (16.2%), and straight (6.3%). Its size was found to be larger in males (P = 0.014 for depth, P < 0.001 for length). No significant difference existed between the sides. The height and age of the specimens did not correlate with the size of the iliopsoas notch. Furthermore, neither the femoral neck version, the lesser trochanteric version, nor the angle between the neck of the femur and the lesser trochanter influenced the dimensions of the iliopsoas notch. CONCLUSION: The iliopsoas notch is a consistent landmark of the acetabulum, although its anatomical appearance is widely variable. The iliopsoas notch arrangement cannot be predicted perioperatively based on the morphology of the proximal femur. The various shapes and sex-related differences detected in this study could be used for designing new hip implants or could be utilized during cup positioning in total hip arthroplasty.

Arthroscopic and endoscopic techniques for iliopsoas release in THA are safe and effective: a systematic review of the literature.

BACKGROUND: Hip replacement surgery is highly effective in relieving pain and improving mobility in patients with various hip conditions. However, some patients develop groin pain after surgery, often due to iliopsoas impingement (IPI), which can be challenging to diagnose. Conservative treatments are initially recommended, but when these are not effective, surgical options may be considered. This study aims to evaluate the clinical outcomes, success and failure rates, revision rates, and complications associated with arthroscopic and endoscopic surgery for IPI, thereby providing a comprehensive understanding of the effectiveness and risks of these surgical interventions. MATERIALS AND METHODS: A systematic review was conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including a thorough search of five main databases: PubMed, Scopus, Embase, Medline, and Cochrane. Eligible articles were meticulously evaluated according to predefined criteria for levels of evidence (LoE), with retrospective studies assessed using the Coleman Methodology Score (mCMS). This systematic review was registered in the International Prospective Registry of Systematic Reviews (PROSPERO). RESULTS: Among the 16 included studies, 431 patients with 434 hips underwent either endoscopic or arthroscopic tenotomy. Both techniques showed favorable outcomes, with arthroscopic tenotomy demonstrating slightly higher success rates than endoscopic tenotomy. Common complications included mild pain and occasional infections, with recurrence observed in some cases. Both techniques offer direct visualization of prosthetic components and potential preservation of psoas function. CONCLUSIONS: Arthroscopic and endoscopic iliopsoas tenotomy are effective treatments for alleviating symptoms and improving hip function in patients with IPI post-total hip arthroplasty (THA). LEVEL OF EVIDENCE: IV.

Spontaneous retroperitoneal haematoma in severe dengue: A case report.

Dengue is endemic in over 100 countries worldwide, predominantly in the subtropical and tropical regions and the incidence has been increasing globally. Patients with severe dengue may develop massive bleeding, disseminated intravascular coagulopathy and multi-organ failure. Bleeding may occur in various body cavities and muscles; however, bleeding in the retroperitoneal space is uncommon. We report a case of a 37-year-old gentleman who presented with a 4-day history of fever associated with chills and rigours. On Day 6 of illness, he complained of left lumbar and left iliac fossa pain which was aggravated by movement. A computed tomography angiography scan of the abdomen showed the presence of a retroperitoneal haematoma, left iliopsoas and quadratus lumbarum intramuscular haematoma with active bleeding and left abdominal wall muscles haematoma. His condition gradually improved after multiple blood transfusions and he gained full recovery. Spontaneous retroperitoneal haematoma is an uncommon complication of severe dengue infection. Early diagnosis based on high index of clinical suspicion using appropriate imaging will aid in prompt management of these cases and may prevent deaths.

Iliopsoas muscle to visceral fat ratio on CT predicts Cushing's syndrome in elderly females with adrenal tumors.

There is no computed tomography (CT)-based numerical index for predicting Cushing's syndrome (CS) in patients with adrenal incidentalomas. We tested the hypothesis that the iliopsoas muscle (Ip-M) to visceral fat (V-fat) ratio (IVR) on CT may predict CS in elderly female patients with adrenal tumors. We examined the V-fat area, subcutaneous fat (S-fat) area, Ip-M area, V-fat/S-fat ratio, and IVR at the third lumbar vertebra (L3) level using abdominal CT in female patients aged ≥50 years with cortisol-producing adrenal tumor diagnosed with CS or non-functioning adrenal tumor (NFT) in the derivation cohort. We performed receiver operating characteristic (ROC) analysis to evaluate the diagnostic value of the V-fat/S-fat ratio and IVR for predicting CS. We assessed the usefulness of the IVR in a separate validation cohort. In the derivation cohort, the IVR was significantly lower in the 9 patients with CS than in the 15 patients with NFT (p < 0.001). In ROC analysis with a cut-off value of 0.067, the IVR showed a sensitivity of 100%, specificity of 80.0%, positive likelihood ratio (PLR) of 5.000, and negative likelihood ratio (NLR) of 0.000. The area under the curve was significantly higher for the IVR than for the V-fat/S-fat ratio (0.933 vs. 0.704, respectively, p = 0.036). In 23 patients in the validation cohort, the IVR demonstrated a PLR of 5.714 and an NLR of 0.327. The novel IVR index, based on single-slice CT at the L3 level, predicted CS in elderly female patients with adrenal tumors.

A randomized controlled trial of iliopsoas plane block vs. femoral nerve block for hip arthroplasty.

BACKGROUND: Iliopsoas plane block (IPB) is a novel analgesic technique for hip surgery that retains quadriceps strength. However, evidence from randomized controlled trial is remains unavailable. We hypothesized that IPB, as a motor-sparing analgesic technique, could match the femoral nerve block (FNB) in pain management and morphine consumption, providing an advantage for earlier functional training in patients underwent hip arthroplasty. METHODS: We recruited ninety patients with femoral neck fracture, femoral head necrosis or hip osteoarthritis who were scheduled for unilateral primary hip arthroplasty were recruited and received either IPB or FNB. Primary outcome was the pain score during hip flexion at 4 h after surgery. Secondary outcomes included quadriceps strength and pain scores upon arrival at post anesthesia care unit (PACU) and at 2, 4, 6, 24, 48 h after surgery, the first time out of bed, total opioids consumption, patient satisfaction, and complications. RESULTS: There was no significant difference in terms of pain score during hip flexion at 4 h after surgery between the IPB group and FNB group. The quadriceps strength of patients receiving IPB was superior to those receiving FNB upon arrival at PACU and at 2, 4, 6 and 24 h after surgery. The IPB group showed a shorter first time out of bed compared to the FNB group. However, there were no significant differences in terms of pain scores within 48 h after surgery, total opioids consumption, patient satisfaction and complications between the two groups. CONCLUSION: IPB was not superior to FNB in terms of postoperative analgesia for hip arthroplasty. However, IPB could serve as an effective motor-sparing analgesic technique for hip arthroplasty, which would facilitate early recovery and rehabilitation. This makes IPB worth considering as an alternative to FNB. TRIAL REGISTRATION: The trial was registered prior to patient enrollment at the Chinese Clinical Trial Registry (ChiCTR2200055493; registration date: January 10, 2022; enrollment date: January 18, 2022; https://www.chictr.org.cn/searchprojEN.html ).

Ultrasound-Guided Iliopsoas Bursal Injections for Management of Iliopsoas Bursitis After Total Hip Arthroplasty.

BACKGROUND: Iliopsoas tendonitis can cause persistent pain after total hip arthroplasty (THA). Nonoperative management of iliopsoas tendonitis includes anti-inflammatory drugs and image-guided corticosteroid injections. This study evaluated the efficacy of ultrasound-guided corticosteroid injections (US-CSIs) for iliopsoas tendonitis following THA. METHODS: We retrospectively reviewed 42 patients who received an US-CSI for iliopsoas tendonitis after primary THA between 2009 and 2020 at a single institution. Outcomes including reoperation, groin pain at last follow-up, additional intrabursal injection, and Harris Hip Score (HHS) were evaluated at a minimum of 1 year. Cross-table lateral radiographs (36 patients) or computed tomography scans (6 patients) were reviewed to determine if anterior cup overhang was present, indicating a mechanical etiology of iliopsoas tendonitis. Descriptive statistics and univariate comparison of HHS preinjection and postinjection were performed, with alpha < 0.05. RESULTS: Among the 22 patients who did not have cup overhang, four (18.2%) had persistent groin pain at mean follow-up of 40 months (range, 14-94) after US-CSI. Three patients had a second injection; none had groin pain at most recent follow-up. No patients required acetabular revision. Mean HHS improved from 74 points (range, 52-94 points) to 91 points (range, 76-100 points; P < .001) at last follow-up. Among the 20 patients who had anterior cup overhang, five underwent acetabular revision after only temporary pain relief from injection. Groin pain was resolved in all revised patients at mean follow-up of 43 months (range, 12-60) after revision. Of the remaining 15 patients, five had persistent groin pain at mean follow-up of 35 months (range, 12-83). Mean HHS improved from 69 points (range, 50-96 points) preinjection to 81 (range, 56-98 points; P = .007) at last follow-up. CONCLUSION: Resolution of groin pain was demonstrated in 78.6% of patients in the cohort; however, those who did not have acetabular overhang had higher rates of success. The overall revision rate was 11.9%. US-CSI appears to be safe and effective in the diagnosis and treatment of iliopsoas tendonitis following primary THA. LEVEL OF EVIDENCE: Level IV, Therapeutic Study.

Risk Factors for Iliopsoas Tendinopathy After Anterior Approach Total Hip Arthroplasty.

BACKGROUND: Iliopsoas tendinopathy is a cause of groin pain following total hip arthroplasty (THA). With the anterior approach becoming increasingly popular, our aim was to determine the prevalence of iliopsoas tendinopathy following anterior approach THA, to identify risk factors and to determine an influence on patient-reported outcomes. METHODS: This is a retrospective case-control study of prospectively recorded data on 2,120 primary anterior approach THA (1,815 patients). The diagnosis of iliopsoas tendinopathy was based on (1) persistent postoperative groin pain, triggered by hip flexion; (2) absence of dislocation, infection, loosening, or fracture; and (3) decrease of pain after fluoroscopy-guided iliopsoas tendon sheet injection with xylocaine and corticosteroid. Outcomes included hip reconstruction (inclination/anteversion and leg-length), complication rates, reoperation rates, and patient-reported outcomes including Hip disability and Osteoarthritis Outcome Score. RESULTS: Forty four patients (46 THAs) (2.2%) were diagnosed with iliopsoas tendinopathy. They were younger than patients who did not have iliopsoas tendinopathy (51 years [range, 27-76] versus 62 years [range, 20-90]; P < .001). Logistic regression analyses demonstrated that younger age (P < .001) and presence of a spine fusion (P = .008) (odds ratio 4.6) were the significant predictors of iliopsoas tendinopathy. These patients had lower Hip disability and Osteoarthritis Outcome scores, reported more often low back pain (odds ratio 4.8), and greater trochanter pain (odds ratio 5.4). CONCLUSION: We found an incidence of 2.2% of iliopsoas tendinopathy patients after anterior approach THA that compromised outcomes. Younger age and previous spine fusion were identified as most important risk factors. These patients were 5 times more likely to report low back pain and greater trochanter pain post-THA.

Incidence and Risk Factors of Iliopsoas Tendinopathy After Total Hip Arthroplasty: A Radiographic Analysis of 1,602 Hips.

BACKGROUND: Iliopsoas tendinopathy (IPT) can cause persistent groin pain and lead to dissatisfaction after total hip arthroplasty (THA). This study aimed to report the characteristics, incidences, risk factors, and treatment outcomes of IPT after THA. METHODS: We reviewed primary THAs performed at a single institution between January 2012 and May 2018. Clinical and radiographic analyses were performed on 1,602 THAs (1,370 patients). Patient characteristics, component sizes, inclination and anteversion angles, and antero-inferior cup prominence (≥8 millimeters (mm)), were compared between the groups with and without IPT. Changes in teardrop to lesser trochanter distance were measured to estimate changes in leg length and horizontal offset caused by THA. Logistic regression models were used to identify the risk factors for IPT. IPT was identified in 53 hips (3.3%). RESULTS: Patients with IPT had greater leg lengthening (12.3 versus 9.3 mm; P = .001) and higher prevalence of antero-inferior cup prominence (5.7 versus 0.4%; P = .002). There was no significant difference in inclination, anteversion, and horizontal offset change between the two groups. In multivariate analyses, greater leg lengthening, prominent acetabular cup, women, and higher body mass index were associated with IPT. All patients reported improvement in groin pain after arthroscopic tenotomy, while 35.7% with nonoperative management reported improvement (P < .001). CONCLUSIONS: Symptomatic IPT occurred in 53 (3.3%) of the 1,602 primary THAs. Our findings suggest that leg lengthening as well as prominent acetabular cup in THAs can be associated with the development of IPT. Arthroscopic tenotomy was effective in relieving groin pain caused by IPT.

The Anterior Position of the Hip Center of Rotation Is Related to Anterior Cup Protrusion Length and Symptomatic Iliopsoas Impingement in Primary Total Hip Arthroplasty.

BACKGROUND: Iliopsoas impingement (IPI) is an important complication after total hip arthroplasty (THA), and anterior cup protrusion is believed to be its main cause; however, the relationship between the hip center of rotation (COR) and symptomatic IPI or cup protrusion remains poorly understood. Therefore, the present study investigated these relationships. METHODS: The medical records of 138 patients who underwent unilateral primary THA were retrospectively reviewed. There were 8 patients (5.8%) who had symptomatic IPI. The COR and cup protrusion length measured with 2 methods were assessed on computed tomography. Risk factors for symptomatic IPI and the relationship between the COR and protrusion length were evaluated. RESULTS: Logistic regression analyses showed that anteroposterior position of the COR, sagittal cup protrusion length (SCPL) at the COR, and both axial and SCPLs at the most anterior margin of the cup were related to symptomatic IPI. Multivariable regression analyses showed that acetabular offset was related to axial protrusion length at the COR, and anteroposterior position of the COR was related to both axial and sagittal protrusion lengths at the most anterior margin of the cup. CONCLUSION: Anterior position of the cup was related to symptomatic IPI and both axial and sagittal protrusion lengths at the most anterior margin of the cup. Anterior reaming and cup protrusion should be avoided as much as possible to prevent symptomatic IPI.

Iliopsoas haematoma during extracorporeal membrane oxygenation: A registry report from the COVID-19 critical care consortium across 30 countries.

INTRODUCTION: Iliopsoas haematoma (IPH) during extracorporeal membrane oxygenation (ECMO) is a rare bleeding complication that can be fatal due to its progression to abdominal compartment syndrome, but its incidence and risk factors are not well known. We have previously reported an IPH incidence rate of 16% in Japan. Among possible reasons for this high incidence, ethnicity has been hypothesised to play a role. Therefore, we used an international multi-centre cohort registry to test this hypothesis by determining the incidence rate of IPH. METHODS: This study was performed using the COVID-19 Critical Care Consortium database, conducted in 30 countries across five continents between 3 January 2020, and 20 June 2022. RESULTS: Overall, 1102 patients received ECMO for COVID-19-related acute respiratory distress syndrome. Of them, only seven were reported to have IPH, indicating an incidence rate of 0.64%, with comparable rates between the countries. The IPH group tended to have a higher mortality rate (71.4%) than the non-IPH group (51%). CONCLUSIONS: Overall incidence of IPH in the studied COVID-19 ECMO cohort was 0.64%. Most cases were reported from Japan, Belgium, and Italy. In our study, this rare complication did not appear to be confined to Asian patients. Due to the high fatality rate, awareness about the occurrence of IPH should be recognised.

Ultrasonography Facilitates the Diagnosis of Traumatic Iliopsoas Hemorrhage: A Report of Two Cases with Different Patterns.

We report two cases of traumatic iliopsoas hemorrhage, without hemoperitoneum, initially detected by ultrasound. Flexion hip contracture in the first case and incomplete femoral nerve palsy in the second case alerted the sonographer to the possibility of traumatic iliopsoas hemorrhage. The first case involved a 54-year-old man who complained of progressive right flank pain and difficulty in walking after falling to the ground. The second case involved a 34-year-old man who complained of severe lower back pain and numbness and weakness of the left leg after a motorcycle accident. In both cases, iliopsoas hemorrhage was confirmed on subsequent multidetector computed tomography.

Nocardia elegans primary iliopsoas abscess: A case report and literature review.

Nocardia species are rare causative agents of psoas abscess, more frequently occurring as part of disseminated infection. Only sporadic cases have been reported so far, with Nocardia asteroides and Nocardia farcinica being the most common causative agents. Nocardia elegans is an opportunistic pathogen, accounting for only 0.3-0.6% of infections caused by Nocardia species, usually affecting the respiratory tract.In this study, a previously healthy 74-year-old man was admitted to the University Hospital of Heraklion with fever and intense pain radiating from the lumbar region to the groin and the left thigh, increasing with movement. Imaging findings revealed a large abscess in the left iliopsoas. Blood and pus aspirate cultures yielded a pure culture of Nocardia that was identified by 16S rRNA sequence as N. elegans. The patient was successfully treated with drainage of the abscess along with administration of ceftriaxone, linezolid and trimethoprim-sulfamethoxazole. To our knowledge, this is the first report of iliopsoas abscess caused by N. elegans. Early, accurate diagnosis and timely treatment with drainage of the abscess and long-term administration of antimicrobial agents optimize the outcome.

Diagnosis and Treatment of Musculotendinous Deficiencies of the Hip.

Musculotendinous deficiencies related to iliopsoas tendinitis and abductor mechanism disruption following total hip arthroplasty (THA) are frequently under diagnosed and can be frustrating to surgeons and devastating to patients with painful THAs with normal appearing radiographs. Current peer-reviewed evidence is presented for diagnosis and treatment options for these two musculotendinous deficiencies. While these musculotendinous deficiencies are treatable, prevention during the primary THA is ideal, and special attention should be taken into consideration for optimized acetabular cup size and position, optimized hip biomechanics, and preservation and protection of the abductor tendon insertion to the greater trochanter.

Artificial Neural Network Detects Hip Muscle Forces as Determinant for Harmonic Walking in People after Stroke.

Many recent studies have highlighted that the harmony of physiological walking is based on a specific proportion between the durations of the phases of the gait cycle. When this proportion is close to the so-called golden ratio (about 1.618), the gait cycle assumes an autosimilar fractal structure. In stroke patients this harmony is altered, but it is unclear which factor is associated with the ratios between gait phases because these relationships are probably not linear. We used an artificial neural network to determine the weights associable to each factor for determining the ratio between gait phases and hence the harmony of walking. As expected, the gait ratio obtained as the ratio between stride duration and stance duration was found to be associated with walking speed and stride length, but also with hip muscle forces. These muscles could be important for exploiting the recovery of energy typical of the pendular mechanism of walking. Our study also highlighted that the results of an artificial neural network should be associated with a reliability analysis, being a non-deterministic approach. A good level of reliability was found for the findings of our study.

Association of Outcomes of Spinal Cord Stimulation for Chronic Low Back Pain and Psoas Measurements Based on Size of Iliopsoas Muscles.

INTRODUCTION: Patients experience variable long-term improvement in chronic back pain despite successful spinal cord stimulation (SCS) trials. Iliopsoas (IP) size has been shown to differ between patients with low back pain and healthy controls. In this study, we examine whether the IP muscle cross-sectional area (CSA) is associated with SCS outcomes. MATERIALS AND METHODS: We examined patients for whom we had lumbar MRIs 6.3 years prior to SCS and baseline and one-year outcome data. Percent change from baseline to one year was calculated for Numeric Rating Scale (NRS), Oswestry Disability Index (ODI), Beck Depression Inventory (BDI), Pain Catastrophizing Scale (PCS), and McGill Pain Questionnaire (MPQ). Correlations between IP muscle CSA, ratio of iliopsoas muscle size to the vertebral body area (P/VBA), and the ratio of iliopsoas muscle size to BMI (P/BMI) were examined. Sex differences were considered. RESULTS: A total of 73 subjects were included in this study, including 30 females and 43 males. Males had significantly larger IP (males 15.70 ± 0.58, females 9.72 ± 0.43; p < 0.001), P/VBA (males 1.00 ± 0.04, females 0.76 ± 0.03; p < 0.001), and P/BMI ratio (males 0.51 ± 0.02, females 0.32 ± 0.01; p < 0.001) than females. In females, P/VBA predicted NRS worst pain scores (ß = 0.82, p = 0.004, r2 = 0.55) and BDI (ß = 0.59, p = 0.02, r2 = 0.24). In males, P/BMI was a significant predictor of BDI outcome scores (ß = 0.45, p = 0.03, r2 = 0.16). Males who had more muscle mass measured by iliopsoas size had more depression as measured using BDI (p = 0.03, r = 0.61). Females with less muscle mass measured by P/VBA also experienced more depression (p = 0.02, r = 0.74). CONCLUSIONS: Our study showed that psoas measurements correlated with various pain outcomes specifically. P/VBA was most predictive in females and P/BMI in males. Depression correlated with P/BMI, reinforcing the complex relationship between depression and constant chronic pain. Tertile analyses further showed a relationship between iliopsoas CSA and depression in males and females. We provide preliminary data of sex-specific psoas measurements as a risk factor for worse SCS outcomes.

Multiple iliopsoas tendons: a cadaveric study and treatment implications for internal snapping hip syndrome.

PURPOSE: This cadaveric study aimed at describing the anatomical variations of the iliopsoas complex. METHODS: The iliopsoas complex was dissected unilaterally in 28 formalin-embalmed cadavers-13 males and 15 females with a mean age of 85.6 years. The number, courses and widths of the iliacus and psoas major tendons were determined. Patients with previous hip surgery were excluded. The following measurements were taken from the mid-inguinal point: the distance to the point of union of the psoas major and iliacus tendon; and the distance to the most distal insertion of iliopsoas. RESULTS: The presence of single, double and triple tendon insertions of iliopsoas were found in 12, 12 and 4 of the 28 specimens, respectively. When present, double and triple tendons inserted separately onto the lesser trochanter. The average length of the iliopsoas tendon from the mid-inguinal point to the most distal attachment at the lesser trochanter was 122.3 ± 13.0 mm. The iliacus muscle bulk merged with psoas major at an average distance of 24.9 ± 17.9 mm proximal to the mid-inguinal point. In all cases, the lateral-most fibres of iliacus yielded a non-tendinous, muscular insertion on to the anterior surface of the lesser trochanter and the femoral shaft, rather than joining onto the main iliopsoas tendon(s). The average total width of the psoas major tendon decreased with an increasing number of tendons: 14.6 ± 2.2 mm (single tendon), 8.2 ± 3.0 mm (2 tendons present) and 5.9 ± 1.1 mm (3 tendons present) (P < 0.001). CONCLUSIONS: The results of this study suggest that multiple tendinous insertions of iliopsoas are present as an anatomical variant in more than 50% of the population. The non-tendinous muscular insertion of the iliopsoas on to the anterior surface of the lesser trochanter and femoral shaft found represents a novel anatomical variant not previously described. LEVEL OF EVIDENCE: Level V.