Hip Capsule Research Articles

Capsule Closure of Periportal Capsulotomy for Hip Arthroscopy

Multiple approaches for management of the hip capsule during hip arthroscopy for femoroacetabular impingement syndrome have been reported. Capsular closure is advocated in the setting of larger capsulotomies, including interportal and T-capsulotomies, to reduce the risk of iatrogenic instability or microinstability of the hip. The periportal capsulotomy technique has been described for conservative management of the capsule that would not necessitate closure. However, hip arthroscopy for patients with ligamentous laxity or joint hypermobility may warrant capsule closure or plication even with use of conservative capsulotomy techniques. We introduce a technique for closure of periportal capsulotomy as a means to repair or plicate the hip capsule in the at-risk hypermobile patient.

Biomechanical Evaluation of 4 Suture Techniques for Hip Capsular Closure.

Background:The most reliable suture technique for capsular closure after a capsulotomy remains unknown.Purpose:To determine which suture technique best restores native stability after a 5-cm interportal capsulotomy.Study Design:Controlled laboratory study.Methods:Ten human cadaveric hip specimens were tested using a 6-degrees-of-freedom robotic arm in 7 states: intact, capsular laxity, 5-cm capsulotomy, standard suture, shoelace, double shoelace, and Quebec City slider (QCS). Rotational range of motion (ROM) was measured across 9 tests: flexion, extension, abduction, abduction at 45° of flexion, adduction, external rotation, internal rotation, anterior impingement, and log roll. Distraction (ie, femoral head translation [FHT]) was measured across a range of flexion and abduction angles.Results:When compared with the native state, the 5-cm capsulotomy state showed the largest laxity increases on all tests, specifically in external rotation ROM (+13.4°), extension ROM (+11.5°), and distraction FHT (+4.5 mm) (P < .001 for all). The standard suture technique was not significantly different from the 5-cm capsulotomy on any test and demonstrated significantly more flexion ROM than the double shoelace suture (+1.41°; P = .049) and more extension ROM (+5.51°; P = .014) and external rotation ROM (+6.03°; P = .021) than the QCS. The standard suture also resulted in significantly higher distraction FHT as compared with the shoelace suture (+1.0 mm; P = .005), double shoelace suture (+1.4 mm; P < .001), and QCS (+1.1 mm; P = .003). The shoelace, double shoelace, and QCS techniques significantly reduced hip laxity when compared with the 5-cm capsulotomy state, specifically in external rotation ROM (respectively, –8.1°, –7.8°, and –10.2°), extension ROM (–6.3°, –7.3°, and –8.1°), and distraction FHT (–1.8, –2.2, and –1.9 mm) (P ≤ .003 for all). These 3 techniques restored native stability (no significant difference from intact) on some but not all tests, and no significant differences were observed among them on any test.Conclusion:Hip capsule closure with the standard suture technique did not prevent postoperative hip instability after a 5-cm capsulotomy, and 3 suture techniques were found to be preferable; however, none perfectly restored native stability at time zero.Clinical Relevance:The shoelace, double shoelace, and QCS suture techniques are recommended when closing the hip capsule.

Collagen I in the Hip Capsule Plays a Role in Postoperative Clinical Function in Patients With Developmental Dysplasia of the Hip.

The aims of the present study is to evaluate the roles of collagen I and III in the hip capsule in the postoperative clinical function of patients with developmental dysplasia of the hip (DDH). Hip capsules from 155 hips of 120 patients were collected during surgery. The patients were divided into three groups according to age: I: 2–3.5 years; II: 3.5–5 years; and III: 5–6 years. Patient clinical function and radiographic outcomes were evaluated with the McKay scores and Severin classification. The expression of collagen I and III was detected through immunohistochemistry and quantitative reverse transcription polymerase chain reaction (RT-PCR) and analyzed according to age, sex, degree of dislocation and McKay classification. All patients received open reduction and pelvic osteotomy and/or femoral shortening osteotomy and achieved good results on the basis of postoperative X-ray imaging. The average follow-up time was 3.4 years (range 2–4.3 years). There were no changes in the expression of collagen III in the different groups. The expression of collagen I according to age and sex was not significantly different. Lower expression of collagen I was observed in DDH patients with a higher degree of dislocation according to the Tonnis grade. The highest expression of collagen I was detected in the group with poor clinical function according to the McKay classification. Collagen I is correlated with the degree of dislocation and is a risk factor for poor clinical function in DDH patients. Collagen I is correlated with the degree of hip dislocation and poor clinical function in DDH patients.

Female Patients and Decreased Hip Capsular Thickness on Magnetic Resonance Imaging Associated With Increased Axial Distraction Distance on Examination Under Anesthesia: An In Vivo Study

To investigate the relation of hip capsular thickness as measured on preoperative magnetic resonance imaging (MRI) and intraoperative hip joint axial distraction distance on an examination under anesthesia. A retrospective review of primary arthroscopic hip procedures performed between November 2018 and June 2021 was conducted. The inclusion criteria included a diagnosis of femoroacetabular impingement syndrome and preoperative radiographic imaging and MRI. Fluoroscopic images were obtained at 0 lb and 100 lb of axial traction force. Total distraction distance was calculated by comparing the initial joint space with the total joint space at 100 lb. Hip capsular thickness was measured on MRI. Analysis was conducted using multiple linear regression, independent-samples t tests, and Mann-Whitney U tests. Eighty patients were included. Bivariable regression showed an association between an increased distraction distance and female sex (β= 4.303, R= 0.561, P < .001), as well as decreased anterior axial (β= -1.291, R= 0.365, P < .001) and superior coronal (β= -1.433, R= 0.501, P < .001) capsular thickness. Multivariable regression (R= 0.645) showed an association between an increased distraction distance and female sex (β= 3.175, P < .001), as well as decreased superior coronal capsular thickness (β= -0.764, P= .022). Independent-samples t tests showed that female patients had significantly decreased superior coronal capsular thickness (2.92 ± 1.14 mm vs 3.99 ± 1.15 mm, P < .001). Female sex and decreased hip capsular thickness in the superior aspect of the coronal plane on magnetic resonance scans were found to be predictors of increased hip joint axial distraction distance on examination under anesthesia prior to hip arthroscopy, with anterior axial capsular thickness being a moderate predictor. Poor predictors of distraction distance were posterior axial and inferior coronal capsular thickness, age, body mass index, and lateral center-edge angle. Female patients were also found to have thinner hip capsules in the superior region, which may explain the association between female patients and increased distraction. These findings further characterize the relation between capsular thickness and hip laxity. Level IV, case series.

In vivo magnetic resonance imaging study of the hip joint capsule in the flexion abduction external rotation position

Although the flexion abduction external rotation (FABER) test is a useful hip provocation test, hip soft tissue characteristics in the FABER position remain unclear. This study investigated the in-vivo joint capsule characteristics, including its articular cavity area and relation to the fat pad surrounded by the joint capsule and pericapsular muscles, in the FABER position using magnetic resonance imaging. Thirteen hips from 13 healthy volunteers were analyzed. The images were obtained, with the participant hips at 15°-extension, 45°-flexion, and in the FABER position, to analyze the articular cavity size and fat pad and calculate these ratios to size of the femoral neck. The articular cavity area and its ratio to the femoral neck were significantly greatest in the FABER position, followed by those in the hip flexion and extension. Additionally, the area of the fat pad in the inter-pericapsular muscle space and its ratio to the femoral neck in the FABER position were significantly larger than those in the hip flexion and, as a tendency, larger than those in hip extension. To the best of our knowledge, this is the first in-vivo study to show the interrelationship among the joint capsule, pericapsular muscles, and fat pad in the FABER position.

Integrity of the hip capsule measured with magnetic resonance imaging after capsular repair or unrepaired capsulotomy in hip arthroscopy.

BACKGROUNDCurrent literature shows no clear answer on the question how to manage the capsule after hip arthroscopy. Regarding patient reported outcome measures there seems to be no difference between capsular repair or unrepaired capsulotomy.AIMTo evaluate and compare the integrity of the hip capsule measured on a magnetic resonance imaging (MRI) scan after capsular repair or unrepaired capsulotomy.METHODSA case series study was performed; a random sample of patients included in a trial comparing capsular repair vs unrepaired capsulotomy had a postoperative MRI scan. The presence of a capsular defect and gap size were independently evaluated on MRI.RESULTSA total of 28 patients (29 hips) were included. Patient demographics were comparable between treatment groups. There were 2 capsular defects in the capsular repair group and 7 capsular defects in the unrepaired capsulotomy group (P = 0.13). In the group of patients with a defect, median gap sizes at the acetabular side were 5.9 mm (range: 2.7-9.0) in the repaired and 8.0 mm (range: 4.5-18.0) in the unrepaired group (P = 0.462). At the muscular side gap sizes were 6.6 mm (range: 4.1-9.0) in the repaired group and 11.5 mm (range: 3.0-18.0) in the unrepaired group (P = 0.857). The calculated Odds ratio (OR) for having a capsular defect with an increasing lateral center-edge (CE) angle was 1.12 (P = 0.06). The OR for having a capsular defect is lower in the group of patients that underwent a labral repair with an OR of 0.1 (P = 0.05).CONCLUSIONThere is no significant difference in capsular defects between capsular repair or unrepaired capsulotomy. Regarding clinical characteristics our case series shows that a larger CE angle increases the likelihood of a capsular defect and the presence of a labral repair decreases the likelihood of a capsular defect.

Protocol for a multicenter prospective cohort study evaluating arthroscopic and non-surgical treatment for microinstability of the hip joint

BackgroundMicroinstability of the hip joint is a proposed cause of hip pain and reduced function in young individuals. The underlying mechanism is thought to be extraphysiological hip motion due to bony deficiency and/or soft tissue deficiency or decreased soft tissue function. Recently, the condition has gained increased attention, and despite the fact that treatment today includes both non-surgical and surgical approaches, there is limited evidence on diagnostic specificity and treatment effects. The aim of this study is to evaluate clinical outcomes of both non-surgical and surgical treatment for microinstability of the hip joint.MethodsA multicenter prospective cohort study is planned to evaluating the outcome of physical therapy aimed at stabilizing the hip joint, as well as arthroscopic plication of the hip joint capsule, if the physical therapy fails. Outcomes will be evaluated using hip-specific patient-reported outcome measures: the short version of the International Hip Outcome Tool and the Copenhagen Hip and Groin Outcome Score, strength and function tests, health-related quality of life as determined using the European Quality of Life-5 Dimensions and the European Quality of Life-Visual Analog Scale, sports activity levels according to the Hip Sport Activity Scale, and reported complications. Patients will be evaluated at 6, 12 and 24 months after each treatment.DiscussionIt is important to evaluate the clinical outcomes of both non-surgical and surgical treatment for suspected microinstability of the hip joint, and the planned prospective evaluation will contribute to the understanding of non-surgical as well as surgical treatment outcomes, including complications.Trial registrationClinicaltrials.gov: NCT04934462. Registered June 22 2021.

Fluoride increases the susceptibility of developmental dysplasia of the hip via increasing capsular laxity triggered by cell apoptosis and oxidative stress in vivo and in vitro

The etiology of developmental dysplasia of the hip (DDH) is multifactorial, including breech presentation and hip capsular laxity. In particular, hip laxity is the main contributor to DDH by changing the ratio and distribution of collagens. Also, fluoride (F) affects collagens from various tissue besides bone and tooth. To investigate the association of DDH and excessive F intake, we conducted this research in lab on cell and animal model simultaneously. We established animal model of combination of DDH and F toxicity. The incidence of DDH in each group was calculated, and hip capsules were collected for testing histopathological and ultrastructural changes. The primary fibroblasts were further extracted from hip capsule and treated with F. The expression of collagen type I and III was both examined in vivo and in vitro, and the level of oxidative stress and apoptosis was also tested identically. We revealed that the incidence of DDH increased with F concentration. Furthermore, the oxidative stress and apoptosis levels of hip capsules and fibroblasts both increased after F exposure. Therefore, this study shows that excessive F intake increases susceptibility to DDH by altering hip capsular laxity in vivo and in vitro respectively. We believe that F might be a risk factor for DDH by increasing hip laxity induced by triggering fibroblast oxidative stress and apoptosis.

Open technique for supra-acetabular pin placement in pelvic external fixation: a cadaveric study

BackgroundStandard supra-acetabular pin placement still needs fluoroscopic guidance, which is technically demanding for an untrained surgeon due to the unfamiliar fluoroscopic view and the risk of damaging some structures. The risks associated with the open technique without fluoroscopy have not yet been investigated, despite the palpable entry point and large bony corridor for rapid insertion in the limited time available for the management of unstable pelvic fracture patients. The aim of this study was to compare the open technique without fluoroscopy to the fluoroscopically assisted percutaneous technique for the positioning of supra-acetabular screws in cadavers without pelvic instability.Materials and methodsThe open technique for half-pin placement was compared to standard fluoroscopic guidance in 16 hemipelves (8 cadavers). The open technique was first performed on one side in each cadaver after simple randomization, followed by standard fluoroscopic guidance on the other side. In the open technique group, a Schanz pin 5 mm in diameter and 200 mm in length was inserted in the area just above the anteroinferior iliac spine (AIIS) and aimed with a medial inclination of 20° and a cephalad inclination of 10–20° after a 2 cm pilot drill hole had been established. Standard fluoroscopically guided pin placement was performed on the other side. Fluoroscopic assessment was conducted after final pin placement on both sides. The lateral femoral cutaneous nerve of the thigh (LFCN) and the hip capsule were identified via the Smith–Peterson approach. After complete dissection of soft tissue, it was clearly apparent that pin penetration was conducted outside the bony corridor.ResultsThe LFCN was found to be in a risk zone near the pin (mean distance, 15 mm; range, 0–30 mm). One LFCN may have been injured in the fluoroscopic guidance group. The mean medial inclination of the pin was 19.8° (range, 5–40°) and the mean cephalad inclination was 11.5° (range 0–20°) in the open technique group. The mean medial inclination of the pin was 30.4° (range, 20–45°) and the mean cephalad inclination was 19.3° (range, 2–35°) in the fluoroscopic guidance group. The mean distance of the pin entry point from the AIIS was 11.1 mm (range, 0–35 mm) in the open technique group. The mean distance of the entry point of the pin from the AIIS was 15.1 mm (range, 0–25 mm) in the fluoroscopic guidance group. The mean hip joint capsule distance was 12 mm (range, 8–25 mm). No joint penetration was observed in the open technique group, compared to one joint penetration in the fluoroscopic guidance group. No sciatic notch penetration was found in either group, but pin penetration outside the external cortex of the ilium was found only in the open technique group, in 4 hemipelves.ConclusionsThis study shows that the freehand technique performed by experienced trauma surgeons may be as acceptable as controlled pin insertion under image intensification for selecting the proper entry point and stabilizing the anterior pelvic ring.

The Iliofemoral Bounce Test: Identifying Hip Capsular Insufficiency

Background: Insufficiency of hip capsular structures has recently gained recognition as a cause of pre-arthritic hip pain, leading to hip joint instability and progressive chondrolabral injury. An accurate evaluation of capsular integrity can help orthopedic surgeons plan capsular management prior to hip arthroscopy. Indications: The proposed iliofemoral bounce test is meant to be applied preoperatively for identification of hip capsular integrity when microinstability is suspected or in the setting of revision hip arthroscopy. Technique Description: After induction of general anesthesia and complete muscle relaxation, the patient is placed in a supine figure-four position by placing the foot of the pathologic hip on the contralateral knee. Two examination techniques are performed: (1) The examiner places one hand on the patient’s contralateral anterior superior iliac spine and applies consecutive downward pressure in a “rocking” manner to the pelvis; (2) the examiner applies a preload and release force to the flexed knee (examined hip), with the contralateral pelvis stabilized, and observes the response of the knee to this loads. Results: Technique 1: The expected physiologic response in a preserved joint is a “bounce” of the contralateral hip (examined hip), evidenced by an up-and-down movement of the knee in response to the rocking movement applied. This movement reflects the integrity and functionality of the hip capsule ligaments’ elastic recoil forces, allowing the hip to remain in a stable state in response to destabilizing forces. In contrast, when capsular insufficiency is present, a lack of bouncing will be observed due to unrestricted external rotation of the hip to constrain the hip joint. Technique 2: In a preserved joint capsule, the knee will return to its preload position, while in capsular insufficiency, no bouncing of the knee will be observed. Discussion/Conclusion: The iliofemoral bounce test is a novel, dynamic, and reproducible examination technique for clinicians to evaluate patient’s true hip capsular integrity and for preoperative identification of the proper capsular management, either with a less invasive capsulotomy or performing a capsular closure, plication or even reconstruction, when necessary.

Handle With Care: The Anterior Hip Capsule Plays a Key Role in Daily Hip Performance.

Background:Passive energy storage and return has long been recognized as one of the central mechanisms for minimizing the energy cost needed for terrestrial locomotion. Although the iliofemoral ligament (IFL) is the strongest ligament in the body, its potential role in energy-efficient walking remains unexplored.Purpose:To identify the contribution of the IFL to the amount of work performed by the hip muscles for normal, straight-level walking.Study Design:Controlled laboratory study.Methods:Straight-level walking of 50 healthy and injury-free adults was simulated using the AnyBody Modeling System. For each participant, the bone morphology and soft tissue properties were nonuniformly scaled. The superior and inferior parts of the IFL were represented by 2 springs each, and a linear force-strain relation was defined. A parameter study was conducted to account for the uncertainty surrounding the mechanical properties of the IFL. The work required from the gluteus, quadriceps, iliopsoas, and sartorius with and without inclusion of the IFL was calculated. Analysis of variance with subsequent post hoc paired t test was used to test the significance of IFL presence on the required mechanical work.Results:During walking, the strain in the IFL reached a median of 18.7% (95% CI, 8.0%-26.5%), with the largest values obtained at toe-off. With the IFL undamaged and fully operational, the effort required by the hip flexor muscles was reduced by a median of 54% (99% CI, 45%-62%) for the iliopsoas and by a median of 41% (99% CI, 27%-54%) for the sartorius muscles. The inclusion of the IFL did not significantly alter the work required by the gluteus and the quadriceps.Conclusion:The findings emphasized the key role the IFL plays in hip flexion by working synergistically with the hip musculature.Clinical Relevance:The importance of the contribution of the IFL to the hip flexors warrants careful handling and repair of these ligaments in cases of surgery and structural damage.

Anatomical features of the iliocapsularis muscle: a dissection study.

PurposeIliocapsularis (IC) overlies the anteromedial hip capsule and is an important landmark in anterior approaches to hip arthroplasty. Previously believed to be part of iliacus, few publications describe the prevalence, attachments, fibre direction, blood supply, innervation, and size of IC. This study was aimed to determine these anatomical features using embalmed bodies and whether they vary between sides, sex, and age.MethodsThirty-eight formalin-fixed adult bodies were dissected and the prevalence, presence of a connective tissue raphe, attachments, fibre direction, blood supply, and innervation, were documented. Length and width were measured, and significant differences were investigated with t tests.ResultsIliocapsularis was present in all bodies examined, originating from the inferior border of the anterior inferior iliac spine, and inserting 20 mm distal to the lesser trochanter in 54 muscles (71%). Iliocapsularis was supplied by a thin branch from the femoral nerve and by branches of the lateral circumflex femoral and deep femoral arteries and veins. Muscle fibre direction was from superolateral to inferomedial. Mean length was 116.8 ± 11.2 mm and width was 12.8 ± 3.1 mm, with no significant differences between sides, sex, and age.ConclusionThis was the first study to document the venous drainage and compare the dimensions with sides, sex, and age, using adult bodies. However, the true function of IC is still unknown. Iliocapsularis is a constant muscle, distinct from iliacus, which is relevant to orthopaedic surgeons and physical rehabilitation specialists, particularly for postoperative patient care.Supplementary InformationThe online version contains supplementary material available at 10.1007/s00276-022-02905-y.

Surgical treatment of femoroacetabular impingement syndrome : Arthroscopy-mini-open-surgical hip dislocation

Femoroacetabular impingement syndrome (FAIS) is one of the most common prearthritic hip deformities. Since FAIS is amechanical pathology, surgical correction of the underlying deformity is the sole causal treatment. If surgery is indicated, a surgical technique that results in complete deformity correction with least morbidity should be selected. Due to advancements in techniques and instruments, most pathologies in FAIS can nowadays be addressed arthroscopically. Hip arthroscopy can be successfully performed if the locations of the pathologies are anterior and lateral. In special cases and indications-like periarticular pathologies, pathologies of the hip capsule and large labral reconstructions and transplantations, acombination of arthroscopy with amini-open approach is advantageous. Furthermore, the learning curve of hip arthroscopy can be improved with an additional open approach. Global and circumferential pathologies still have to be addressed in surgical hip dislocation to avoid residual deformities. Finally, extraarticular osteotomies have to be considered in cases with significant rotational deformities.

Особливості формування капсули суглоба після антенатальної дії антигену

У роботі із застосуванням морфометричного, гістологічного, гістохімічного та статистичного методів досліджена динаміка становлення капсули кульшового суглоба білих лабораторних щурів протягом постнатального періоду після внутрішньоплідного введення антигену. Встановлено, що антенатальна дія антигену призводить до збільшення кількості лімфоцитів, зокрема PNA+-лімфоцитів, у капсулі суглоба. На цьому тлі спостерігається збільшення частки клітин, основної речовини та еластичних волокон при одночасному зменшенні вмісту колагенових волокон, порушення розподілу полісахаридів та фібробластів, що вказує на розвиток диспластичних процесів у кульшовому суглобі та може розглядатися як провідний рушійний фактор розвитку коксартрозу. Експериментально отримано доліхостеномелію як візуальний клінічний прояв дисплазії.

Arthroscopic Hip Capsular Reconstruction Using Iliotibial Band Allograft as a Salvage Option for Unrepairable Capsular Defects Demonstrates Good Survivorship and Improved Patient-Reported Outcomes

To describe patient outcomes 3 to 5 years after arthroscopic hip capsule reconstruction. Between January 2007 and December 2016, patients aged 18 to 50 years who underwent arthroscopic hip capsular reconstruction using an Iliotibial band allograft by the senior author and had minimum of 3-year follow-up were identified. Patients were excluded if they had previous open hip surgery, advanced osteoarthritis (Tönnis grade >2), significant acetabular dysplasia (lateral center edge angle <20°), avascular necrosis, or Legg-Calve-Perthes disease. Outcome scores including the Hip Outcome Score (HOS)-Activities of Daily Living scale, modified Harris Hip Score, HOS-Sports scale, SF-12, and Western Ontario & McMaster Universities Osteoarthritis Index were compared in addition to failure rate, revision rate, and patient satisfaction rate with the outcome (range, 1-10). All patients were assessed by the senior author pre- and postoperatively. Thirty-nine patients met the inclusion criteria. The mean age of the cohort was 32 ± 10 years, with 6 male and 33 female patients. The average number of previous hip arthroscopy surgeries was 2 ± 1. Six patients (15%) converted to total hip arthroplasty at an average of 2.1 years (range 7 months to 6 years) following capsular reconstruction. Four patients required revision hip arthroscopy after the arthroscopic capsular reconstruction. All arthroscopic revisions occurred in female patients with the primary intraoperative finding of capsulolabral adhesions at the time of revision. At mean follow-up of 4.3 years (range 3-6.8 years), the 29 patients who did not require subsequent surgery had significant improvements from preoperatively to postoperatively in HOS-Activities of Daily Living and HOS-Sport with 90% reaching minimal clinically important difference. All other scores showed significant improvement. Survival for patients not requiring total hip arthroplasty was 86% at 3 years, with a mean survival of 5.7 years (95% confidence interval 4.97-6.4). Arthroscopic hip capsular reconstruction with iliotibial band allograft is a successful treatment option for patients with symptomatic capsular defects, demonstrating improved patient-reported outcomes maintained at mean follow-up time of 4 years. This technique offers restoration of the anatomic structure and function of the capsular ligaments to improve pain and instability. IV, case series.

CLINICAL RELEVANCE OF HETEROTOPIC OSSIFICATION OF HIP AND PELVIC BONES MUSCLES AND LIGAMENTS

Objectives: Heterotopic ossification is a formation of bone at unusual sites. The present study is aimed to observe the ossification of transverse acetabular ligament, obturator membrane and gluteus maximus muscle in hip bones and fibrous capsule of hip joints and ossification of sacrotuberous and sacrospinous ligaments, erector spinae aponeurosis in pelves, and bilateral ankylosis of sacroiliac joints. Methods: The study was performed on 128 dried human hip bones and six pelves of unidentified sex and age, in the Department of Anatomy. An ossified muscles and ligaments of hip and pelvic bones were observed and their measurements were recorded using Vernier calipers. Results: The present study showed the incidence of completely ossified transverse acetabular ligament in four hip bones, that is, 3.12% with completely ossified fibrous capsule of hip joint on the left side. The incidence of bony spurs along the margin of Obturator Foramen in four left hip bones is 6.25% along with the ossification of the gluteus maximus muscle on dorsal aspect of ilium. Out of six pelves, one pelvis presented complete ossification of erector spinae aponeurosis bilaterally on the dorsal surface of the sacrum along with complete ossification of sacrotuberous ligament of the right side and sacrospinous ligament of the left side along with bilateral ankylosed sacroiliac joint of pelvis. Conclusions: The knowledge of these abnormal ossifications of hip bones and pelvis may be of immense help to orthopedicians, surgeons, neurosurgeons, and radiologists to come to differential diagnosis and plan treatment accordingly.

Native bone and joint infections caused by extended-spectrum β-lactamase-producing Enterobacterales: experience of a reference centre in the Greater Paris area

Antibiotic treatment of native osteomyelitis caused by extended-spectrum β-lactamase-producing Enterobacterales (ESBL-PE) is a challenge. Limited epidemiological and outcome data are available. This retrospective cohort study included osteomyelitis patients with ESBL-PE infections treated in a reference centre for bone and joint infections (BJIs) between 2011-2019. Twenty-nine patients with native BJI (mean age, 44.4 ± 15.7 years) were analysed. Fifteen cases were paraplegic patients with ischial pressure sores breaching the hip capsule. Other cases included eight other hip infections, four tibial infections and two foot infections. Infections were mostly polymicrobial (n=23; 79.3%), including Staphylococcus aureus (n=13; 8 methicillin-resistant). Klebsiella pneumoniae (n=13) was the most frequent ESBL-producing species identified, followed by Escherichia coli (n=10), including 3 E. coli/K. pneumoniae co-infections, and Enterobacter spp. (n=9). ESBL-PE were rarely susceptible to fluoroquinolones (n=4; 13.8%). Most therapies were based on carbapenems (n=22) and combination therapies (n=19). The median duration of treatment was 41 (5-60) days. Primary control of the infection was achieved in 62.1% (18/29) of cases and up to 86.2% after second look surgeries, after a median follow-up of 6 (1-36) months. Infection with ESBL-producing K. pneumoniae was associated with failure (P=0.001), whereas age, infection location, prior colonisation and antimicrobial therapy were not found to be predictors of outcome. ESBL-PE native BJIs are often polymicrobial and fluoroquinolone-resistant infections caused by K. pneumoniae, highlighting the need for expert centres with pluridisciplinary meetings with experienced surgeons.

The effect of platelet-rich plasma on chondrocyte healing in traumatic dislocation of the hip in a rat model

Background/Aim: Traumatic hip dislocations (THD) are orthopedic emergencies and significant complications such as cartilage degeneration can be reduced with early reduction. This study aimed to examine the effect of platelet-rich plasma (PRP) on cartilage cells in one-, two- or 8-hours prolonged hip dislocation. Methods: We used 24 Sprague-Dawley rats in this study and divided them into three main groups based on whether their hips were in the protruding position for one, two, or eight hours. Each main group was further divided into two subgroups, with the right hips constituting the experimental group and the left hips, the control group. Traumatic hip dislocation modeling was performed surgically on both hips of the rats under anesthesia in the same session. After both dislocated joints were reduced and the hip capsules were sutured, platelet-rich plasma was administered to the right hips. After 1 week, all rats were sacrificed, their femoral heads were excised and subjected to histopathological examination. Terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL) testing was used to show chondrocyte apoptosis in the femoral head. The apoptotic index (AI) showing the ratio of cartilage cells to apoptosis was calculated histopathologically. A comparison of apoptotic indices was made between the groups. Results: The AIs of the one-, two- and eight hours-long hip dislocation groups were 0.012 (0.005), 0.023 (0.011), 0.046 (0.012), respectively (P

Polymyalgia rheumatica in 18-fluorodeoxyglucose-positron-emission-tomography/computed tomography : Improvement in diagnostic accuracy and differentiation from rheumatoid arthritis

The diagnosis of patients with polymyalgia rheumatica (PMR) has relied upon the clinical examination of symptoms and laboratory parameters of inflammation until now. Currently, the use of different imaging modalities is being explored, including ultrasound, MRI and PET. The aim was to evaluate the diagnostic value of 18-fluorodeoxyglucose-positron-emission-tomography/computed tomography (18F-FDG-PET/CT) for PMR, in order to improve the sensitivity and specificity of diagnosing PMR and to improve the differential diagnosis of rheumatoid arthritis (RA). Examinations using 18F-FDG-PET/CT of 284 rheumatological patients, including 97 patients with PMR, were retrospectively evaluated over a44-month period. Furthermore, 13regions changed by inflammation were analysed via athree-dimensional region of interest (ROI) measurement with determination of maximum standardized uptake values (SUVmax), followed by statistical analyses. Patients with PMR presented significantly elevated uptake in all regions examined (p < 0.001), compared with acontrol group treated for rheumatological diseases. The method with the highest diagnostic relevance was represented by the combination of four SUVmax values of both anterolateral hip capsules and both ischial tuberosities, reaching asensitivity of 91.3% and aspecificity of 97.6% with acut-off of 11.0 SUV at the initial diagnosis of PMR patients who had not yet received any immunosuppressive therapy. Patients with RA could be significantly distinguished from those with PMR at initial diagnosis in the same anatomical regions (p < 0.001).

Spatial distribution of loose connective tissues on the anterior hip joint capsule: a combination of cadaveric and in-vivo study

Recently, pathological changes in the fat pad on the anterior inferior iliac spine (AIIS), between the proximal rectus femoris and joint capsule, have been highlighted as a cause of anterior hip pain. However, precise fat pad features, such as the spatial distribution distal to the AIIS, histological features, and in vivo tissue elasticity, remain unclear. This study aimed to investigate the morphological characteristics of the fat pad on the AIIS. Four hips from four cadaveric donors were both macroscopically and histologically investigated, and eight hips from four volunteers were assessed using ultrasonography. The fat pad on the AIIS was also surrounded by the iliopsoas and gluteus minimus, extending distally to the superficial portion of the vastus lateralis, and the anterior portion of the gluteus maximus tendon. Histological analysis revealed that the fat pad was composed of loose connective tissue. Based on the ultrasonography, the shear wave velocity in the fat pad was significantly lower than that in the joint capsule. Conclusively, the pathological adhesion between the joint capsule and pericapsular muscles, if caused by fat pad fibrosis, may occur following the abovementioned fat pad spatial distribution.