Femoral Head-neck Research Articles

PINCER MORPHOLOGY IS NOT ASSOCIATED WITH DEVELOPMENT OF HIP OSTEOARTHRITIS WITHIN 10 YEARS; A NATIONWIDE PROSPECTIVE COHORT STUDY (CHECK)

Purpose: Pincer morphology is an overcoverage of the acetabulum relative to the femoral head (figure 1). During motion of the hip, this might lead to an abutment between the acetabular rim and femoral head-neck junction, a process referred to as pincer-type femoroacetabular impingement. This abnormal contact between the femoral head and acetabulum might potentially lead to damage of the labrum and articular cartilage. However, to date, results on the relationship between pincer morphology and hip osteoarthritis (OA) have been conflicting and previous prospective cohort studies typically did not find an association.

Internal fixation using fully threaded cannulated compression screws for fresh femoral neck fractures in adults

ObjectivesInternal fixation with multiple cannulated compression screws is an optional treatment for femoral neck fracture. Recently, fully threaded cannulated compression screws (FTCCS) have been introduced to fix fresh femoral neck fractures (FNF). The purpose of this study was to investigate the effectiveness of FTCCS.Patients and methodsPatients with FNF fixed by multiple FTCCS from February 1st, 2014 to August 31st, 2017 were included in this study. They were followed for at least 12 months postoperatively. Nonunion, osteonecrosis of the femoral head (ONFH), fixation failure, reoperation, and femoral neck shortening (FNS) were used to evaluate the outcomes. Risk factors including age, sex, fracture side, fracture displacement, fracture stability, fixation configuration, and screw numbers were analyzed.ResultsA total of 113 patients including 67 males and 46 females with an average age of 48.4 ± 13.4 years were included. The mean duration of follow-up was 27.1 months (range: 12–51 months). The incidence of nonunion, ONFH, fixation failure, and reoperation was 15.9%, 22.1%, 8.8%, and 24.8%, respectively. The rates of nonunion and reoperation were significantly higher in displaced fractures and unstable fractures. And patients with an unstable fracture had a higher risk of internal fixation failure. The median length of FNS was 2.9 mm (interquartile range: 0.9–6.5 mm, range: 0–17.5 mm). Age was a significant risk factor for FNS.ConclusionsThe screw fixation method with FTCCS provided encouraging clinical results which may be a rational choice for the treatment of fresh FNF. Displaced fractures and unstable fractures were attributed to the higher incidence of complications.Trial registration: ChiCTR, ChiCTR1800017200. Registered 17 July 2018-Retrospectively registered, http: www.chictr.org.cn/showprojen.aspx?proj=29182.

Hip Microinstability: Understanding a Newly Defined Hip Pathology in Young Athletes

Microinstability is an increasingly recognized diagnosis in young athletes presenting with hip pain. Causes of microinstability may include abnormality of the hip bony anatomy, acetabular labral tears, joint capsule laxity or injury, and muscle dysfunction. Borderline hip dysplasia is an increasingly recognized factor predisposing to microinstability. The capsuloligamentous structures of the hip, particularly the iliofemoral ligament, provide important restraints to femoral head motion, and iatrogenic defects can predispose patients to instability after surgery. Injury to the acetabular labrum may disrupt its important hip-stabilizing properties including the suction seal and improved acetabular depth. Hip muscle weakness or imbalance may result in increased femoral head motion within the acetabulum. The diagnosis of hip microinstability can be challenging, and the history is often nonspecific. Physical examination maneuvers include the anterior apprehension, prone instability, axial distraction, and abduction-hyperextension-external rotation tests. Radiographic features may include borderline hip dysplasia, femoral head-neck junction cliff sign, and an elevated femoral-epiphyseal acetabular roof index. Magnetic resonance arthrography may demonstrate a capsular defect, capsular thinning, or labral pathology. Diagnostic intra-articular injection of anesthetic can confirm the intra-articular nature of the pathology. Management of hip microinstability focuses on strengthening the dynamic stabilizers of the hip through focused physical therapy. Surgery may be considered in recalcitrant cases where symptoms persist despite optimization of hip stabilizer strength. In such cases, addressing the primary source of instability through labral repair or reconstruction and capsular repair or plication can be considered. In highly selected cases, surgery can result in excellent outcomes.

MRI-based synthetic CT of the hip: can it be an alternative to conventional CT in the evaluation of osseous morphology?

MRI is the gold standard for soft tissue evaluation in the hip joint. However, CT is superior to MRI in providing clear visualization of bony morphology. The aim of this study is to test the equivalency of MRI-based synthetic CT to conventional CT in quantitatively assessing bony morphology of the hip. A prospective study was performed. Adult patients who underwent MRI and CT of the hips were included. Synthetic CT images were generated from MRI using a deep learning-based image synthesis method. Two readers independently performed clinically relevant measurements for hip morphology, including anterior and posterior acetabular sector angle, acetabular version angle, joint space width, lateral center-edge angle, sharp angle, alpha angle, and femoral head-neck offset on synthetic CT and CT. Inter-method, inter-reader, and intra-reader reliability and agreement were assessed using calculations of intraclass correlation coefficient, standard error of measurement, and smallest detectable change. The equivalency among CT and synthetic CT was evaluated using equivalency statistical testing. Fifty-four hips from twenty-seven participants were included. There was no reported hip pathology in the subjects. The observed agreement based on reliability and agreement parameters indicated a strong degree of concordance between CT and synthetic CT. Equivalence statistical testing showed that all synthetic CT measurements are equivalent to the CT measurements at the considered margins. In healthy individuals, we demonstrated equivalency of MRI-based synthetic CT to conventional CT for the quantitative evaluation of osseous hip morphology, thus obviating the radiation exposure of a pelvic CT examination. •MRI-based synthetic CT images can be generated from MRI using a deep learning-based image synthesis method. •MRI-based synthetic CT is equivalent to CT in the quantitative assessment of bony hip morphology in healthy individuals. •MRI-based synthetic CT is promising for use in preoperative diagnosis and surgery planning.

Anterior acetabular coverage and femoral head-neck measurements predict postoperative anterior impingement: A simulation study.

The aim of this simulation study was to evaluate the relationship of elements of anterior acetabular coverage and femoral head-neck shape with the occurrence of postoperative anterior impingement after curved periacetabular osteotomy (PAO). Sixty-two patients with symptomatic developmental dysplasia of the hip who had undergone curved PAO were selected. The likelihood of developing postoperative anterior impingement was explored through simulations of the range of motion by collision detection of the pelvis and femur. Postoperative anterior impingement was defined as impingement that occurred during postoperative bone flexion <105° or postoperative internal rotation <20° at 90° flexion. The three-dimensional center-edge (CE) angles, acetabular and femoral versions, radiographic alpha angles of the femoral head, combination angles of anterior CE and alpha angles, and combined anteversions of acetabular and femoral versions were compared between patients with postoperative anterior impingement and nonimpingement. A receiver operator characteristic (ROC) analysis was conducted to determine thresholds of the examined radiographic parameters and calculate their accuracy for predicting postoperative anterior impingement. A multivariate analysis was performed to test whether combined anteversion, anterior CE angle, and combination angle are associated with excellent modified Harris Hip Scores (mHHSs).ROC analysis demonstrated a combination angle ≥108° was predictive of the occurrence of postoperative anterior impingement after curved PAO, which can lead to impaired clinical outcomes. Conversely, a combination angle <108° was significantly associated with mHHS ≥ 90 points. To avoid postoperative anterior impingement, osteochondroplasty of the femoral head or anterior CE angle control should be performed for patients with preoperative combination angles ≥90°.

Elimination of the Femoral Neck in Measuring Femoral Version Allows for Less Variance in Interobserver Reliability.

Background and Objectives: Producing consistent measures of femoral version amongst observers are necessary to allow for an assessment of version for possible corrective procedures. The purpose of this study was to compare two computed tomography (CT)-based techniques for the reliability of measuring femoral version amongst observers. Materials and Methods: Review was performed for 15 patients post-femoral nailing for comminuted (Winquist III and IV) femoral shaft fractures where CT scanograms were obtained. Two CT-based techniques were utilized to measure femoral version by five observers. Results: The mean femoral version, when utilizing a proximal line drawn down the center of the femoral head-neck through CT, was 9.50 ± 4.82°, while the method utilizing the head and shaft at lesser trochanter centers produced a mean version of 18.73 ± 2.69°. A significant difference was noted between these two (p ≤ 0.001). The method of measuring in the center of the femoral head and neck produced an intraclass correlation coefficient (ICC) of 0.960 with a 95% confidence interval lower bound of 0.909 and upper bound of 0.982. For the method assessing version via the center of the head and shaft at the lesser trochanter region, the ICC was 0.993 with a 95% confidence interval lower bound of 0.987 and an upper bound of 0.996. Conclusions: The method of measuring version proximally through a CT image of the femoral head–neck versus overlaying the femoral head with the femoral shaft at the most prominent aspect of the lesser trochanter produces differing version measurements by roughly 10° while yielding an almost perfect interobserver reliability in the new technique. Both techniques result in significantly high interobserver reliability.

Comparison between anterior cuneiform osteotomy and Dunn procedure in the surgical management of unstable severe slipped femoral epiphysis: A case-control study of 41 patients

BackgroundThere is little consensus on the best treatment algorithm for unstable severe slipped capital femoral epiphysis (SCFE). Subcapital osteotomy, which is one of the surgical options, is performed either anteriorly (anterior cuneiform osteotomy, CO) or laterally with trochanteric osteotomy (Dunn procedure, DP). The CO is technically easier and decreases operating time. Moreover, because the DP was the standard in our department before it was replaced by the CO, we had a series of consecutive patients. Therefore, we did a retrospective case-control study in unstable, severe SCFEs treated by CO versus DP, which is to our knowledge the first one aiming to compare: (1) postoperative complications and in particular avascular necrosis, (2) functional outcome, (3) radiologic findings. HypothesisCO is less or just as likely to cause avascular necrosis and has the same clinical and radiologic findings as DP. MethodsA total of 41 patients (24 girls, i.e. 58.5%) were included between 2005 and 2018: 23 in the CO group and 18 in the DP group. The median age was 12.9 years (range, 11.5–14.9) and the median slip angle 70̊ (range, 62.5̊–80̊) with a median follow-up of 3 years (range, 2–4). Preoperative, intraoperative, and postoperative clinical and radiologic parameters (Southwick and alpha angles, and femoral head-neck offset) were analyzed, and all complications were documented. ResultsTwo (8.7%) cases of avascular necrosis were reported in the CO group and 6 (33.3%) in the DP group (p=.11), with an overall rate of avascular necrosis of 19.5% (8/41). Five out of the 41 patients (12.2%) underwent a total hip arthroplasty: 1/23 (4.3%) in the CO group and 4/18 (22.2%) in the DP group (p=.16). Two (9.5%) patients in the CO group and 7 (38.9%) in the DP group developed postoperative limping before any arthroplasty was performed (p=.055). The alpha angle at follow-up (54±6.1̊ vs. 59.1±7.2̊; p=.027), Oxford hip score at follow-up (17/60 [range, 14–20] vs. 23.5 [range, 19–27]) (p=.021), operating time (132 min [range, 103–166] vs. 199.5 min [range, 142–215]) (p=.011) and intraoperative bleeding (250 mL [range, 100–350] vs. 300 mL [range, 197–450]) (p=.088) were more favorable in the CO group than in the DP group. ConclusionsThe CO has similar results to DP in the surgical management of unstable severe SCFE. Level of evidenceIII; retrospective comparative study.

Open MRI assessment of anterior femoroacetabular clearance in active and passive impingement-provoking postures.

AimsCam and pincer morphologies are potential precursors to hip osteoarthritis and important contributors to non-arthritic hip pain. However, only some hips with these pathomorphologies develop symptoms and joint degeneration, and it is not clear why. Anterior impingement between the femoral head-neck contour and acetabular rim in positions of hip flexion combined with rotation is a proposed pathomechanism in these hips, but this has not been studied in active postures. Our aim was to assess the anterior impingement pathomechanism in both active and passive postures with high hip flexion that are thought to provoke impingement.MethodsWe recruited nine participants with cam and/or pincer morphologies and with pain, 13 participants with cam and/or pincer morphologies and without pain, and 11 controls from a population-based cohort. We scanned hips in active squatting and passive sitting flexion, adduction, and internal rotation using open MRI and quantified anterior femoroacetabular clearance using the β angle.ResultsIn squatting, we found significantly decreased anterior femoroacetabular clearance in painful hips with cam and/or pincer morphologies (mean -11.3° (SD 19.2°)) compared to pain-free hips with cam and/or pincer morphologies (mean 8.5° (SD 14.6°); p = 0.022) and controls (mean 18.6° (SD 8.5°); p < 0.001). In sitting flexion, adduction, and internal rotation, we found significantly decreased anterior clearance in both painful (mean -15.2° (SD 15.3°); p = 0.002) and painfree hips (mean -4.7° (SD 13°); p = 0.010) with cam and/pincer morphologies compared to the controls (mean 7.1° (SD 5.9°)).ConclusionOur results support the anterior femoroacetabular impingement pathomechanism in hips with cam and/or pincer morphologies and highlight the effect of posture on this pathomechanism.Cite this article: Bone Jt Open 2021;2(11):988–996.

Tönnis Grade 1 dysplastic hips have improved patient-reported outcome scores when intraarticular pathology is treated during periacetabular osteotomy.

ABSTRACTIt is unclear whether treatment of intraarticular pathology should be performed during periacetabular osteotomy (PAO) to improve outcomes. Therefore, we asked: (i) What are the clinical results of PAO in patients with and without intraarticular intervention? (ii) Is there a difference in reoperations with and without intraarticular intervention? and (iii) Is there a difference in clinical results and reoperations depending on preoperative Tönnis Grade if intraarticular intervention is performed? Prospective evaluation of 161 PAO in 146 patients was performed. The cohort was 84.5% female, mean age was 26.7 ± 7.9 years and mean follow-up was 2.4 years; 112 hips had Grade 0 changes and 49 hips had Grade 1 changes. Patients were classified into three groups based on treatments during PAO: major (labral repair, femoral head–neck osteochondroplasty), minor (labral debridement, femoral/acetabular chondroplasty) or no intervention. A subset of eight patient-reported outcome measures (PROMs) was analyzed to determine whether the minimal clinically important difference (MCID) was achieved. Major, minor and no intervention groups exceeded the MCID in 5, 8 and 8, of 8 PROMs (P ≥ 0.20), respectively; intraarticular interventions did not influence reoperation-free survival (P ≥ 0.35). By Tönnis Grade, PROMs exceeding MCID decreased in Grade 1 versus 0 receiving no intervention (P < 0.001) but did not decrease for either intervention (P ≥ 0.14); intraarticular interventions did not influence reoperation-free survival (P ≥ 0.38). Overall, intraarticular intervention was associated with excellent PROMs and reoperation-free survival. Although Grade 1 patients had fewer PROM which achieved MCID, intraarticular interventions attenuated this decrease, suggesting a therapeutic advantage of intraarticular procedures for more advanced pathology.

Horror of three synergistic factors in THA: high mechanical stress, dissimilar metals, low elasticity stem: a case report

BackgroundA large-diameter femoral head is effective in preventing dislocation after total hip arthroplasty. However, although rare, catastrophic stem tribocorrosion may occur at the head-stem junction.Case presentationA 70-year-old woman underwent revision surgery 7.5 years after total hip arthroplasty because of catastrophic stem corrosion with dissociation of the metal head (cobalt/chromium) and stem (TiMo12Zr6Fe2). Abnormal levels of cobalt were found in the intra-articular fluid, capsule, hip muscle, and blood. Revision surgery was performed via the direct anterior approach. The well-fixed femoral stem was explanted, and a cemented stainless stem with stainless head was implanted. Three months after the revision surgery, the cobalt concentration in the blood had decreased to normal.ConclusionsStem dissociation in the present case might have been caused by synergistic combination of a 36-mm-diameter femoral head and long neck length offset with high frictional torque, a cobalt-chromium head with a high risk of galvanic corrosion, and a TMZF (TiMo12Zr6Fe2) alloy stem with a low Young’s modulus of elasticity. The combination of these factors must be avoided.

Comprehensive characterization of osseous tissues from impedance measurements by effective medium approximation

A unified mixing (UM) model was developed to derive microstructural information of trabecular bone, i.e., bone volume fraction (BV/TV), from electrical impedance spectroscopy. A distinct advantage of the UM-model over traditional methods, such as equivalent circuit models and multivariate analysis, is that the influence of both the environment (hydroxyapatite) and different inclusions (water, fat, and air) can be taken into account simultaneously. In addition, interactions between the different components such as interfacial polarization can be addressed by a dedicated fitting parameter v. Accordingly, values of BV/TV for different bone samples, e.g., including or not including water, were determined in the higher frequency range of 1–5 MHz. Results showed good agreement with experimental data obtained by micro-computer tomography. In particular, predictions for dielectric parameters that were derived for 3 and 4 MHz were found most promising for the assessment and distinction of osteopathic conditions and differences. This was shown by a clear differentiation of osseous tissues, e.g., the greater trochanter, femoral head, and femoral neck.

Soft Tissue CAM Impingement in Adolescents: MRI reveals impingement lesions underappreciated on x-ray (138)

Objectives:The presence of femoroacetabular impingement (FAI) in adolescents has been established. However, the existence of a non-ossified CAM lesion in adolescent femoracetabular impingement (FAI) is not well described. The purpose of this study is to evaluate the presence of a non-ossified or soft CAM lesion in adolescent patients with FAI.Methods:A review of a prospective cohort of patients with symptomatic FAI in an institutional registry was performed. Subjects were included if they had an MRI and lateral x-ray of the hip (45o Dunn, Cross Table, or frog) at a baseline visit. On MRI, evaluation of the anterolateral femoral head was evaluated using radial, coronal, sagittal, or axial oblique sequences. When a soft CAM lesion was identified (all found between 2-5 o’clock), an alpha angle was performed on MRI and plain radiograph. The cohort of soft CAM lesions was reviewed and differences between radiographic and MRI alpha angles were assessed using a paired T-Test.Results:Thirty-one (9.3%) of 332 hips (mean age 16.4 yrs, range 13.66-19.59 yrs; 83.9% F) were identified with a soft impinging lesion at the femoral head-neck junction on MRI. The most common primary sport was track & field (4), the average duration of symptoms was 92.4 weeks and a majority with insidious onset (77.4%). The average alpha angle on MRI was greater than on x-ray [63.53 ± 7.94o vs 51.25 ± 7.92o; p<.05]. All subjects with soft CAM lesions demonstrated soft tissue consistent with extension of the physis (n=1),thickening of the peri-chondral ring (n=22), or thickening of the periosteum (n=8). Twenty-two of these patients (71%) with soft impingement underwent hip preservation surgery (n=13 labral repairs) with improvements in clinical outcome.Conclusions:In adolescent patients with symptomatic hip impingement, MRI may be useful to identify soft CAM lesions (non-ossified) that are under-represented on x-ray.

Muscle and Hip Contact Forces in Asymptomatic Men With Cam Morphology During Deep Squat.

Cam morphology is defined as an aspherical femoral head-neck junction that causes abnormal contact of the acetabular rim with the anterior hip. Imaging confirmation of the cam morphology, associated with clinical signs and pain in the hip or groin, is characterized as femoroacetabular impingement (FAI) syndrome. Although some individuals with cam morphology do not experience any symptoms, sparse studies have been done on these individuals. Understanding the way asymptomatic individuals generate muscle forces may help us to better explain the progression of the degenerative FAI process and discover better ways in preventing the onset or worsening of symptoms. The purpose of this study was to compare the muscle and hip contact forces of asymptomatic cam morphology (ACM) and FAI syndrome men compared to cam-free healthy controls during a deep squat task. This prospective study compared 39 participants, with 13 in each group (ACM, FAI, and control). Five deep squatting trials were performed at a self-selected pace while joint trajectories and ground reaction forces were recorded. A generic model was scaled for each participant, and inverse kinematics and inverse dynamics calculated joint angles and moments, respectively. Muscle and hip contact forces were estimated using static optimization. All variables were time normalized in percentage by the total squat cycle and both muscle forces and hip contact forces were normalized by body weight. Statistical non-parametric mapping analyses were used to compare the groups. The ACM group showed increased pelvic tilt and hip flexion angles compared to the FAI group during the descent and ascent phases of the squat cycle. Muscle forces were greater in the ACM and control groups, compared to the FAI group for the psoas and semimembranosus muscles. Biceps femoris muscle force was lower in the ACM group compared to the FAI group. The FAI group had lower posterior hip contact force compared to both the control and ACM groups. Muscle contraction strategy was different in the FAI group compared to the ACM and control groups, which caused different muscle force applications during hip extension. These results rebut the concept that mobility restrictions are solely caused by the presence of the cam morphology and propose evidence that symptoms and muscle contraction strategy can be the origin of the mobility restriction in male patients with FAI.

The frequency of the bony parameters of femoroacetabular impingement syndrome in young asymptomatic individuals: a computed tomography study

Objectives: Femoroacetabular impingement syndrome is a painful disorder of the hip formed by movements in the hip joint between the femoral head-neck junction and the acetabular edge. The aim of this study was to determine the prevalence of radiological femoroacetabular impingement syndrome findings in a young, asymptomatic Turkish population. Methods: A total of 1000 abdominal pelvic CT images were collected from patients aged between 18–40 years. Measurements were taken on the CT images of the alpha angle and femoral head offset as signs of cam-type deformity, and of the acetabular version angle and center-edge angle as signs of pincer-type deformity. Results: Femoroacetabular impingement syndrome was determined in 2.3% of the individuals. Pincer type deformity was determined in 56.5%, being 83.3% in females and 47.1% in males. The cam-type deformity was present in 43.5% of all cases, being in 16.7% of the females and in 52.9% of the males. No difference was determined between the genders in respect of alpha angle which is &gt;55°. A head-neck offset which is &lt;8 mm was at a higher rate in females (13.3%) than males. An acetabular anteversion angle which is &lt;15° and centre-edge angle which is &gt;40° was more in males than females at a rate of 11% and 25.2% respectively. Conclusion: The results of this study showed that the incidence of cam-type deformity in the adult males and the incidence of pincer-type deformity in the adult females were lower in the asymptomatic Turkish population than previously reported in literature.

Arthroscopic Treatment of Femoroacetabular Impingement Syndrome with Bone Cyst at Femoral Head-Neck Junction: Case Report and Literature Review

In recent years, with the development of imaging and arthroscopy techniques, and a deep understanding of the pathogenic mechanism of femoroacetabular impingement syndrome (FAI), more and more scholars have gained a greater knowledge of the diagnosis and treatment of the disease. FAI not only has abnormal bone structure, such as cam deformity at the femoral head-neck junction, acetabular osteophyte formation, and bone cyst at the femoral or acetabulum, but also leads to the soft tissue injury of the hip joint, like acetabulum cartilage and labrum lesion, which might accelerate the progression of hip osteoarthritis. The incidence of bone cyst or synovial hernia at the femoral head-neck junction is not rare, which was seen as a sign of impingement. However, there is a paucity of literature about the treatment of bone cyst and the clear standard protocols of treatment, especially large or polycystic cysts. In this study, we reported a case of Cam FAI complicated with a giant bone cyst at the femoral head-neck junction and its characteristics and arthroscopic treatment. We also reviewed relevant documents and summarized the protocols of management of FAI complicated with femoral head-neck bone cyst for clinical reference.

Calcar-guided short-stem total hip arthroplasty: Will it be the future standard? Review and perspectives.

Short stems in total hip arthroplasty (THA) are becoming increasingly popular. In Germany, already 10.4% of all primary THAs are performed using a cementless short stem. The concept of modern, calcar-guided, short stems aims for an individualized reconstruction of the hip anatomy by following the calcar of the femoral neck, a bone- and soft-tissue-sparing implantation technique, and physiological loading. The stem design uses either metaphyseal fixation alone or additional diaphyseal anchoring, depending on the stem alignment and indication. These individualized anchorage types increase the potential indications for the safe use of a short stem. The design features may account for potential advantages of current short stem implants compared with earlier short-stem designs, particularly in cases of reduced bone quality or osteonecrosis of the femoral head and femoral neck fractures. The implantation technique, however, requires distinct knowledge regarding the characteristics of varus and valgus positioning, with the potential for clinical consequences. A learning curve for surgeons new to this technique must be taken into account. Cortical contact with the distal lateral cortex appears to be crucial to provide sufficient primary stability, and the use of intraoperative imaging to identify “undersizing” is highly recommended. Current results of several national registries indicate that calcar-guided short stems are among the most successful implants in terms of mid-term survivorship. However, long-term data remain scarce. This review introduces the characteristics of calcar-guided short-stem THA and summarizes the current evidence.

Patients' Characteristics Can Predict Clinical Outcomes Following Hip Arthroscopy by Reflecting the Patterns of Labral Tears: A Retrospective Observational Study.

To evaluate the relationship between morphological differences in labral tears and clinical features of the hip joint in patients who underwent hip arthroscopy. We retrospectively analyzed data from patients who underwent arthroscopic surgery for the treatment of labral tears. Hip labral tears were morphologically classified as longitudinal peripheral tears (group L), radial fibrillated tears (group FI), radial flaps (group FL), and an unstable labrum (group U). Radiographically, the center-edge angle, acetabular roof obliquity, vertical-center-anterior angle, alpha angle, femoral head-neck offset ratio, and crossover sign were evaluated and compared among the groups. The relationship between labral morphology and these radiographic findings, as well as clinical findings, such as age, gender, preoperative range of hip motion, and the clinical outcomes using modified Harris Hip Score (mHHS) were also examined. This study included fifty patients. Groups L and FI were often observed in late middle-aged patients with relatively shallow acetabular coverage. Group FL tears were frequently observed in young males with radiographic features, such as femoroacetabular impingement (FAI), compared to the other groups. Group U comprised mostly young females with relatively shallow acetabular coverage compared to the other groups. For the postoperative mHHS, group FL showed the best score among all groups, with a significant difference between groups FL and FI (p = 0.034). Our study revealed that morphologically, different labral tears were associated with different clinical features and radiological findings. Especially, our study can provide predictive findings for hip arthroscopists that younger males with FAI show better clinical outcomes when compared to middle-aged females with shallow acetabulum, which is indicative of degenerative hip labral tears. IV case series.

Primary cam morphology; bump, burden or bog-standard? A concept analysis

BackgroundCam morphology, a distinct bony morphology of the hip, is prevalent in many athletes, and a risk factor for hip-related pain and osteoarthritis. Secondary cam morphology, due to existing or...

Reverse distal femoral locking compression plate (DF-LCP), does it fit and how to fit on Asian's proximal femurs? A cadaveric study.

Reverse distal femoral locking compression plates (DF-LCP) have been used as an alternative treatment in complex proximal femur fractures. The purpose of this study was to assess the compatibility of reverse DF-LCP with Asian proximal femurs, to determine the matching patterns and integrate information to establish guidelines for correct application. Twenty-eight adult cadaveric femurs were obtained from 5 males and 9 females with an average age of 69.27years (range 59-85). A contralateral 13-hole DF-LCP was applied with MIPO technique using the vastus ridge as a landmark for Hole A. The first locking screw was inserted through Hole A under fluoroscopic guidance just above the femoral head-neck junction in AP view and centered of the neck in lateral view, followed by three proximal locking screws. The number of screws successfully inserted through the femoral neck, including any penetration of femoral neck, the gap between anterior and posterior borders between plate and bone, the anatomical parameters of proximal femur, and any mismatches between the plate and the bone were recorded. Most of the screws (82.1%) in Holes A, D, E, and F were put into the femoral neck without breaking through. The average distance from the entry point at the vastus ridge to the anterior cortex of the femur was 17.3 ± 2.3mm and from the posterior cortex was 19.46 ± 2.55mm. The anterior gap was 4.93 ± 1.01mm, and the posterior gap was 13.48 ± 1.44mm. The mismatch where the distal part of the plate started to lift off from the bone > 2mm at the 8th hole with an average distance of 2.78 ± 2.01 mm. That distance gradually increased distally to an average of 9.38 ± 6.03mm at the 13th hole. Reverse DF-LCP can fit most proximal femurs in the Asian population and can be used as an alternative implant when performed using an appropriate technique. However, as a relatively consistent mismatch was found at the distal part starting at the 8th hole, so if a plate is longer than 9 holes, the plate contouring should be considered.

SOFT TISSUE CAM IMPINGEMENT IN ADOLESCENTS: MRI REVEALS IMPINGEMENT LESIONS UNDERAPPRECIATED ON X-RAY

Background:The presence of femoroacetabular impingement (FAI) in adolescents has been established. However, the existence of a non-ossified CAM lesion in adolescent femoracetabular impingement (FAI) is not well described.Hypthesis/Purpose:The purpose of this study is to evaluate the presence of a non-ossified or soft CAM lesion in adolescent patients with FAI.Methods:A review of a prospective cohort of patients with symptomatic FAI in an institutional registry was performed. Subjects were included if they had an MRI and lateral x-ray of the hip (45o Dunn, Cross Table, or frog) at a baseline visit. On MRI, evaluation of the anterolateral femoral head was evaluated using radial, coronal, sagittal, or axial oblique sequences. When a soft CAM lesion was identified (all found between 2-5 o’clock), an alpha angle was performed on MRI and plain radiograph. The cohort of soft CAM lesions was reviewed and differences between radiographic and MRI alpha angles were assessed using a paired T-Test.Results:Thirty-one (9.3%) of 332 hips (mean age 16.4 yrs, range 13.66-19.59 yrs; 83.9% F) were identified with a soft impinging lesion at the femoral head-neck junction on MRI. The most common primary sport was track & field (4), the average duration of symptoms was 92.4 weeks and a majority with insidious onset (77.4%). The average alpha angle on MRI was greater than on x-ray [63.53 ± 7.94o vs 51.25 ± 7.92o; p<0.05]. All subjects with soft CAM lesions demonstrated soft tissue consistent with extension of the physis (n=1),thickening of the peri-chondral ring (n=22), or thickening of the periosteum (n=8). Twenty-two of these patients (71%) with soft impingement underwent hip preservation surgery (n=13 labral repairs) with improvements in clinical outcome.Conclusion:In adolescent patients with symptomatic hip impingement, MRI may be useful to identify soft CAM lesions (non-ossified) that are under-represented on x-ray.