Posterior Impingement Research Articles

VIRTUAL IMPINGEMENT TESTS IN 113 PATIENTS UNDERGOING TOTAL HIP ARTHROPLASTY

Hip precautions following total hip arthroplasty (THA) limits flexion, adduction and internal rotation, yet these precautions cause unnecessary psychological stress. This study aims to assess bony and implant impingement using virtual models from actual patient's bony morphology and spinopelvic parameters to deduce whether hip precautions are necessary with precise implant positioning in the Asian population.Individualized sitting and standing sacral slope data of robotic THAs performed at two tertiary referral centers in Hong Kong was inputted into the simulation system based on patients’ pre-operative sitting and standing lumbar spine X-rays. Three-dimensional dynamic models were reconstructed using the Stryker Mako THA 4.0 software to assess bony and implant impingement both anteriorly and posteriorly, with default cup placement at 40° inclination and 20° anteversion. Femoral anteversion followed individual patient's native version. A 36mm hip ball was chosen for all cups equal or above 48mm and 32mm for those below. Anterior impingement was assessed by hip flexion and posterior impingement was assessed by hip extension.113 patients were included. At neutral rotation and adduction, no patients had anterior implant impingement at hip flexion of 100°. 1.7% had impingement at 110°, 3.5% had impingement at 120°, 9.7% had impingement at 130°. With 20° of internal rotation and adduction, 0.8% had anterior implant impingement at hip flexion of 90°, 7.1% had impingement at 100° and 18.5% had impingement at 110°. With the hip externally rotated by 20°, 0.8% of patients had posterior implant impingement, and 8.8% bony impingement at 0° extension.With enabling technology allowing accurate component positioning, hip precautions without limiting forward flexion in neutral position is safe given precise implant positioning and adequate osteophyte removal. Patients should only be cautioned about combined internal rotation, adduction with flexion.

Ankle impingement after extra-articular open fracture of the leg: Full arthroscopic treatment in the supine position

ObjectiveExtra-articular open fractures of the leg often result from high energy trauma. After healing, a painful ankle impingement may occur. In the event of anterior and posterior impingements, arthroscopic treatment may require two surgical positions. We propose an operative strategy to treat anterior and posterior ankle impingement after extra-articular open fracture of the leg. Our hypothesis is that this strategy is simple, effective and with a low risk of complication. Material and methodAnterior ankle impingements were treated by anterior arthroscopy in supine position; anterior and posterior impingements were treated by anterior and posterior arthroscopy in supine position; anterior and posterior impingements associated with retraction of gastrocnemius muscles were treated with anterior arthroscopy in supine position followed by posterior arthroscopy in prone position, and an open tendon lengthening of the calcaneal tendon in the same position. The anterior and posterior arthroscopic release was tested in the cadaver laboratory. Then, the surgical strategy was applied to our patients in our clinical practice. After, we analysed retrospectively the results of the strategy in the first patients treated for a painful ankle impingement after extra-articular open fracture of the leg. The data retrieved were the importance of pain (VAS), the presence of clinical instability, ankle mobility, gastrocnemius retraction and the AOFAS functional score and the post-operative complications. Then, these data were compared before the surgery and at last follow-up. ResultsFrom the cadaver laboratory, anterior and posterior arthroscopic release was possible in all cases without changing position. From our clinical practice, we included 5 patients (3 women and 2 men, mean age 43 years) suffering from an ankle impingement after extra-articular open fracture of the leg (2 patients with isolated anterior impingement, 1 patient with anterior and posterior impingement, and 2 patients with anterior and posterior impingement plus a gastrocnemius retraction). All post-operative parameters (pain, range of motion and AOFAS score) at mean follow-up of 53 months were improved. No post-operative complication was reported. ConclusionWe propose a surgical strategy adapted to the different clinical presentations of ankle impingement after extra-articular open fracture of the leg.

Arthroscopic Management of Posterior Ankle Impingement Syndrome - A Case Series.

Posterior ankle impingement is a common cause of chronic ankle pain. Although nonoperative treatment is initially preferred, there are surgical options if the symptoms are persistent. Minimally invasive arthroscopic procedures reduce surgical trauma and enable an early return to routine activities. We conducted a study including 6 patients who underwent arthroscopic decompression for posterior ankle impingement. Five of them were female patients and one was a male patient. The pathology varied; one had os trigonum (OT), two had stieda processes (SP), and three had OT with posterior osteophyte complex as part of ankle arthritis. In this paper, we discuss the required clinical approach, preoperative investigations, surgical indications, functional outcomes, and complications of arthroscopic treatment. The patients were followed up for a minimum of 6 months and evaluated using American Orthopedic Foot and Ankle Society (AOFAS) score, Visual Analog Scale (VAS), and range of movement (ROM) pre and post-operatively. All the patients reported a significant reduction of pain and an improved ROMs and functional scores at the operated ankles compared to the opposite side. However, one of the patients developed post-operative tingling and numbness at the plantar aspect of the forefoot. Another one developed tingling at the lateral plantar aspect of the foot. One of the patients with SP, had an incomplete excision of the lesion. Ankle arthroscopy is an effective and minimally invasive surgery that has a significant role in managing chronic ankle pain due to posterior impingement that does not respond to conservative management and provides good functional outcomes with minimal complications.

Posterior Ankle Impingement: It's Not Only About the Os Trigonum.

Os trigonum and Stieda process are common etiologies for posterior ankle impingement syndrome (PAIS), and diagnosis is typically made by radiographs, computed tomographic, or magnetic resonance imaging. However, these static tests may not detect associated soft tissue and bony pathologies. Posterior ankle and hindfoot arthroscopy (PAHA) is dynamic, providing at least ×8 magnification with full anatomical visualization. The primary aim of this study was to report the prevalence of associated conditions seen with trigonal impingement treated with PAHA. In this retrospective comparative study, patients who underwent PAHA for PAIS due to trigonal impingement, from January 2011 to September 2016, were reviewed. Concomitant open posterior procedures and other indications for PAHA were excluded. Demographic data were collected with pre- and postoperative diagnosis, arthroscopic findings, type of impingement, location, associated procedures, and anatomical etiologies. Trigonal impingements were divided in os trigonal or Stieda and subgrouped as isolated, with flexor hallucis longus (FHL) disorders, with FHL plus other impingement, and with other impingement lesions. A total of 111 ankles were studied-74 os trigonum and 37 Stieda. Isolated trigonal disorders accounted for 15.3% of PAIS (n = 17). Cases having associated conditions had a mode of 3 additional pathologies. FHL disorders were found in 69.4%, subtalar impingement in 32.4%, posteromedial ankle synovitis in 25.2%, posterolateral ankle synovitis in 22.5%, and posterior inferior tibiofibular ligament impingement in 19.8% of cases. Associated pathologies were observed in 58.6% of cases when FHL was not considered. Significant differences were noted comparing os and Stieda (isolated: 20.3% to 5.4%, P = .040; FHL plus others: 35.1% to 59.5%, P = .015). Trigonal bone (os trigonum or Stieda) was found to cause impingement in isolation in a small proportion of cases even when the FHL was considered part of the same disease spectrum. This should alert surgeons when considering removing trigonal impingement. Open approaches may limit the visualization and assessment of associated posterior ankle and subtalar pathoanatomy, thus possibly overlooking concomitant causes of PAIS. Level III, retrospective comparative study.

Clinical Relevance of Posterior Osteophyte Formation in Ultra-congruent Total Knee Arthroplasty: Midterm Radiographic Rollback and Impingement Analysis.

Posterior femoral condylar osteophytes were frequently observed in patients with the ultra-congruent (UC) deep-dish design prosthesis. Therefore, the purpose of the present study was to verify the clinical relevance of osteophyte formation in the UC design. From March 2014 to February 2018, a comparative study was conducted on 96 knees using the UC design. They were divided into 2 groups (group 1: osteophyte +, group 2: osteophyte -). Intraoperative findings, indirect femoral rollback assessment using 30° flexion and active full flexion lateral radiographs, serial change of the osteophyte, and outcomes were compared. The mean follow-up period was 49.35 ± 3.47 months in group 1 and 47.52 ± 3.37 months in group 2. Posterior component coverage was significantly different between the groups: group 1 exhibited more underhang and group 2 exhibited more overhang (p = 0.022). On the indirect assessment of the femoral rollback, there was a statistically significant difference in deep flexion and change in distance (p < 0.001 and p < 0.001, respectively). There was no statistical difference between the 2 groups in the American Knee Society knee and function score, and group 2 showed significant improvement in pain compared to group 1 in Western Ontario and McMaster University Arthritis Index pain score (p = 0.029). Posterior condylar osteophyte formation was related to posterior impingement. It was more frequently observed in the underhang of the femoral component and insufficient femoral rollback. In addition, it changed with time and caused negative effects, including a gradual decrease in flexion and more pain.

Anterior Ankle Impingement Syndrome With Spur Fragmentation: Is It an Os Talotibiale?

Bone fragments are often found in ankles with anterior bony impingement. However, whether they are detached osteophytes or accessory bones remains unknown. Among the 66 continuously enrolled cases of ankles with anterior bony impingement, 32 had a fragment located at the anterior margin of the tibia. The cases of posterior impingement, lateral instability, osteochondral lesions, or free bodies simultaneously treated were excluded. The enrolled subjects were classified into 2 groups: ankles without (group A) and with remarkable spurs (group B). The patients' backgrounds, location of the fragments, clinical scores, and other parameters required to resume sports were compared. The Japanese Society for Surgery of the Foot (JSSF) ankle rating scale was used to evaluate preoperative and postoperative ankle conditions, and the Self-Administered Foot Evaluation Questionnaire (SAFE-Q) was used to evaluate postoperative sports abilities. Eight (seven subjects) and 11 ankles were classified into groups A and B, respectively, and the mean age of the 18 patients was 25.4 (range, 16-37) years. No statistical differences in patient backgrounds or fragment sizes between the groups existed. In group A, the fragments were located on the lateral plateau in 7 of the 8 ankles, whereas in group B, their locations varied. The patients were followed up for a median of 48 months (range, 24-168). No complications were observed. The postoperative JSSF and SAFE-Q sports activity scores were significantly higher in group A than in group B (P <.01 and <.001, respectively). The postoperative term to return to their original sports activities was significantly shorter in group A (P < .05). Anterior bony fragments of the ankle without a remarkable spur were located at a specific site, and the results of arthroscopic treatment were better than in those with remarkable spurs. Such a fragment may be called an os talotibiale. Level III, retrospective cohort study.

Patterns of ankle injury in soccer: MRI clues to traumatic mechanism.

Understanding the traumatic mechanisms of ankle injuries in soccer is crucial for an accurate and complete MRI diagnosis. Many ankle injuries share universal mechanisms seen in other athletic activities, but certain patterns are found to be more specific and relatively unique to soccer. Ankle impingement syndromes encountered in soccer encompass a spectrum of disorders that include anterior and posterior impingement categories, with anterior impingement representing pathology relatively specific to soccer. Lateral ligamentous sprains are one of the most common injuries; however, there is a higher rate of injuries to the medial structures in soccer as compared to other sports. Ankle fractures are uncommon in soccer while bone contusions and chondral and osteochondral injuries frequently accompany ligamentous sprains. Tendon abnormalities in soccer most commonly result from overuse injuries and typically affect peroneal tendons, posterior and anterior tibialis tendons, and Achilles tendon. Acute Achilles tendon ruptures occur in both recreational players and elite soccer athletes. Tibialis anterior friction syndrome may mimic tibial stress fractures. Long-term sequelae of acute traumatic and chronic overuse ankle injuries in professional soccer players manifest as ankle osteoarthritis that is more prevalent compared to not only the general population, but also to former elite athletes from other sports. This article examines the most common and specific injuries in soccer in order of their frequency.

Stronger Magnets, No Improvements in Accuracy: Comparing Efficacy of 3-T Magnetic Resonance Imaging (MRI) vs 1.5-T MRI in Detecting Associated Lesions in Patients with Lateral Ankle Instability

Category: Ankle Arthritis Introduction/Purpose: Patients with lateral ankle instability often have other associated pathologies, including osteochondral lesions of the talus (OLT), peroneus brevis tears, and intra-articular loose bodies. If left untreated, these pathologies can lead to worsening instability, significant ankle pain, and progressive osteoarthritis. Arthroscopy has historically been the gold standard for diagnosing and treating these abnormalities, while magnetic resonance imaging (MRI) can be useful in preoperative evaluation and planning. Our group’s previous research evaluated a subset of the current sample, focusing on MRI diagnostic accuracy of OLTs, demonstrating that 3-T outperformed 1.5-T. Using a larger sample size, the purpose of this study is to assess the efficacy of 3-T MRI and 1.5-T MRI in diagnosing additional pathologies in patients undergoing Broström Gould procedure for lateral ankle instability. Methods: Following institutional review board approval, a database was obtained for all patients at a single institution who underwent a Broström Gould procedure with a concurrent diagnostic arthroscopy of the tibiotalar joint between 1/1/2014- 6/30/2022. Additionally, patients required a pre-operative ankle MRI for inclusion in the study. Patients who did not undergo a preoperative MRI, diagnostic arthroscopy, and Broström Gould procedure were excluded from the study. Additionally, patients with pre-operative MRIs in which the field strength could not be determined were also excluded from analysis. Patient charts were reviewed to determine the field strength of the preoperative MRIs, the efficacy of 3-T and 1.5-T MRIs in correctly identifying the presence or absence of OLTs, peroneus brevis tears, loose bodies, os trigonum, medial malleolus fractures, lateral malleolus fractures, and posterior impingement lesions. Intraoperative diagnostic arthroscopy findings were utilized as a reference standard. Results: One hundred twelve patients met our inclusion criteria of undergoing preoperative MRI with identifiable field strength, Broström Gould procedure, and diagnostic arthroscopy of the tibiotalar joint. The average age was 35.73 ± 21.01 years; 65 (58.0%) patients were female. Fifty-six (50.0%) patients had a preoperative 3-T MRI and 56 patients had a preoperative 1.5-T MRI. There were no differences observed regarding demographic data between groups. Fifty-one OLTs, 12 peroneus brevis tears, 14 loose bodies, two os trigonum, two medial malleolus fractures, two lateral malleolus fractures, and one posterior impingement lesion were identified in our sample (Figure 1A). Three tesla MRI test characteristics did not significantly differ from the test characteristics of 1.5-T MRI (Figures 1B, 1C). Conclusion: The sensitivity, specificity, and overall diagnostic accuracy of 3-T MRI compared against 1.5-T MRI did not significantly differ regarding each imaging modalities’ efficacy in identifying OLTs, peroneus brevis tears, loose bodies, os trigonum, medial and lateral malleolus fractures, and posterior impingement lesions. These findings demonstrate no significant improvement in the diagnostic accuracy of 3-T MRI over 1.5-T MRI in identifying pathologies associated with lateral ankle instability. While many lesions were correctly identified by both modalities, patients will continue to benefit from undergoing intraoperative arthroscopy to determine the most accurate diagnosis regarding their ankle instability.

Frequency of Os trigonum and Stieda process, determination of its relation with posterior ankle pain and tendinopathy by ankle MRI

ABSTRACT&#x0D; Aim: To investigate the frequency of Os trigonum and Stieda process and the relationship of Os trigonum with other pathologies detected by magnetic resonance imaging (MRI) in patients with posterior ankle pain.&#x0D; Methods: This was a retrospective study conducted by re-examining MRI images obtained between January 2017 and May 2023. The study included 482 patients (496 ankles) who underwent ankle MRI for diagnostic purposes due to posterior or posterolateral ankle pain. MRI images were re-examined for the following parameters: fractures, contusion, tendinosis, ligament injury, arthritis, effusion, presence of Stieda process, posterior ankle bursa impingement, Os trigonum, retrocalcaneal bursitis, ganglion cyst, widespread osteophytes, accessory navicular bone, presence and grade of osteochondritis dissecans, and presence and type of Achilles tendon pathology. &#x0D; Results: The mean age of the participants was 41.96 ± 15.89 (7–83 years), and 51.04% (n = 246) were male. Os trigonum was detected in 17 patients (3.43 %), and none of the cases were bilateral. The likelihood of Os trigonum was significantly higher in males (p = 0.016, OR: 4.725, 95% CI: 1.341 - 16.655). Stieda process was detected in 186 patients (37.5 %). The accessory navicular bone was detected in 8 (1.61%). The percentage of patients with pathological metatarsal fractures was significantly higher in patients with Os trigonum (p = 0.034). The frequency of Stieda process was significantly lower in patients with Os trigonum (p = 0.013, OR: 0.099, 95% CI: 0.013 - 0.755). There were significantly fewer cases of talotibial effusion in the Os trigonum group (p = 0.030).&#x0D; Conclusion: While Os trigonum appears to be significantly more frequent among males, it is less frequent in the presence of the Stieda process and talotibial effusion.

Posterior Hip Impingement at Maximal Hip Extension in Female Patients With Increased Femoral Version or Increased McKibbin Index and Its Effect on Sports Performance.

The location of posterior hip impingement at maximal extension in patients with posterior femoroacetabular impingement (FAI) is unclear. To investigate the frequency and area of impingement at maximal hip extension and at 10° and 20° of extension in female patients with increased femoral version (FV) and posterior hip pain. Cross-sectional study; Level of evidence, 3. Osseous patient-specific 3-dimensional (3D) models were generated of 50 hips (37 female patients, 3D computed tomography) with a positive posterior impingement test and increased FV (defined as >35°). The McKibbin index (combined version) was calculated as the sum of FV and acetabular version (AV). Subgroups of patients with an increased McKibbin index >70° (24 hips) and FV >50° (20 hips) were analyzed. A control group of female participants (10 hips) had normal FV, normal AV, and no valgus deformity (neck-shaft angle, <139°). Validated 3D collision detection software was used for simulation of osseous impingement-free hip extension (no rotation). The mean impingement-free maximal hip extension was significantly lower in patients with FV >35° compared with the control group (15° ± 15° vs 55° ± 19°; P < .001). At maximal hip extension, 78% of patients with FV >35° had osseous posterior extra-articular ischiofemoral hip impingement. At 20° of extension, the frequency of posterior extra-articular ischiofemoral impingement was significantly higher for patients with a McKibbin index >70° (83%) and for patients with FV >35° (76%) than for controls (0%) (P < .001 for both). There was a significant correlation between maximal extension (no rotation) and FV (r = 0.46; P < .001) as well as between impingement area at 20° of extension (external rotation [ER], 0°) and McKibbin index (0.61; P < .001). Impingement area at 20° of extension (ER, 0°) was significantly larger for patients with McKibbin index >70° versus <70° (251 vs 44 mm2; P = .001). The limited hip extension found in our study could theoretically affect the performance of sports activities such as running, ballet dancing, or lunges. Therefore, although not examined directly in this study, these activities are not advisable for these patients. Preoperative evaluation of FV and the McKibbin index is important in female patients with posterior hip pain before hip preservation surgery (eg, hip arthroscopy).

Excessive Femoral Anteversion Leading to Symptomatic Posterior Femoroacetabular Impingement, Cam Deformity of the Posterior Femoral Head-Neck Junction, and Anterior Hip Instability in a Dancer: A Case Report.

An adolescent female dancer with excessive femoral anteversion presented with posterior and anterior hip pain aggravated by poses that required extension and external rotation. Imaging revealed an atypical cam deformity of the posterior head-neck junction. During surgery, the posterior head-neck junction was observed to impinge on the posterior acetabulum with anterior subluxation of the hip. After a derotational femoral osteotomy, the patient experienced resolution of her symptoms. Excessive femoral anteversion can lead to reactive cam deformity, posterior intra-articular impingement, and anterior hip instability in patients who require repetitive hip extension and external rotation, such as ballet dancers.

THRESHOLD FOR ANTERIOR CUP OVERHANG CORRELATED WITH SYMPTOMATIC ILIOPSOAS IMPINGEMENT AFTER TOTAL HIP ARTHROPLASTY: A 268-PATIENT CASE CONTROL STUDY USING CT SCAN

Mechanical irritation or impingement of the iliopsoas tendon accounts for 2–6% of persistent postoperative pain cases after total hip arthroplasty (THA). The most common trigger is anterior cup overhang. CT-scan can be used to identify and measure this overhang; however, no threshold exists for symptomatic anterior iliopsoas impingement. We conducted a case–control study in which CT-scan was used to define a threshold that differentiates patients with iliopsoas impingement from asymptomatic patients after THA.We analyzed the CT-scans of 622 patients (758 CT-scans) between 2011 and 2020. Out of this population we identified 136 patients with symptoms suggestive of iliopsoas impingement. Among them, 6 were subsequently excluded: three because the diagnosis was reestablished intra-operatively (one metallosis, two anterior instability related to posterior prosthetic impingement) and three because they had another obvious cause of impingement (one protruding screw, one protruding cement plug, one stem collar), leaving 130 patients in the study (impingement) group. They were matched to a control group of 138 patients who were asymptomatic after THA. The anterior cup overhang (anterior margin of cup not covered by anterior wall) was measured by an observer (without knowledge of the clinical status) on an axial CT slice based on anatomical landmarks (orthogonal to pelvic axis).The impingement group had a median overhang of 8 mm [IQR: 5 to 11] versus 0 mm [IQR: 0 to 4] for the control group (p&lt;.001). Using ROC curves, an overhang threshold of 4 mm was best correlated with a diagnosis of impingement (sensitivity 79%, specificity 85%, PPV = 75%, NPV = 85%).Pain after THA related to iliopsoas impingement can be reasonably linked to acetabular overhang if it exceeds 4 mm on a CT scan. Below this threshold, it seems logical to look for another cause of iliopsoas irritation or another reason for the pain after THA before concluding impingement is present.

Injury prevention and physiotherapy procedures for ankle injuries in ballet dancers

The aim of this study was to investigate the most frequent, effective and up-to-date injury prevention and physiotherapy procedures used in relation to ballet dancers’ ankle injuries. A literature review with a qualitative analysis was performed using the following databases: PubMed, SAGE, ScienceDirect, PlosOne and Cochrane Library. The inclusion criteria were: both genders, age &gt; 18, journal impact factor &gt; 0, age of study ≤ 10 years and the following search keywords were used: “ankle”, “injury”, “ballet”, “dancers”, “physiotherapy”, “physical therapy” and “prevention”. A total of 520 articles were found, out of which six were determined to be appropriate according to the inclusion and exclusion criteria. They dealt with the prevention/rehabilitation of ankle sprains (N=2), tendinopathy of the Achilles tendon (N=2), tendinitis of the m. hallucis longus (N=4), rupture of the Achilles tendon (N=2), and anterior (N=3) and posterior (N=4) impingement syndrome. It was found that for injury prevention in ballet, strengthening and stretching exercises are the most often used methods, while rest, ice therapy, muscle strengthening exercises, foot braces and dance technique optimisation are the most frequently used methods in injury management. These seem to also be the most up-to-date injury prevention and physiotherapy procedures, while the most effective procedures could not be retrieved due to a lack of relevant studies, which prevented the quantitative comparison of their effectiveness. The published clinical evidence endorses physiotherapy/kinesiotherapy as an effective ankle injury prevention and management modality in ballet dancers, although additional studies with a better quality of methodology are required.

Preoperative MR imaging for hip dysplasia : Assessment of associated deformities and intraarticular pathologies

Developmental dysplasia of the hip (DDH) is aknown reason for hip pain for adolescents and young adults. Preoperative imaging is increasingly recognized as an important factor due to the recent advances in MR imaging. The aim of this article is to give an overview of preoperative imaging for DDH. The acetabular version and morphology, associated femoral deformities (cam deformity, valgus and femoral antetorsion) and intraarticular pathologies (labrum and cartilage damage) and cartilage mapping are described. After an initial evaluation with AP radiographs, CT or MRI represent the methods of choice for the preoperative evaluation of the acetabular morphology and cam deformity, and for the measurement of femoral torsion. Different measurement techniques and normal values should be considered, especially for patients with increased femoral antetorsion because this could lead to misinterpretation and misdiagnosis. MRI allows analysis of labrum hypertrophy and subtle signs for hip instability. 3DMRI for cartilage mapping allows quantification of biochemical cartilage degeneration and yields great potential for surgical decision-making. 3D-CT and, increasingly, 3DMRI of the hip to generate 3Dpelvic bone models and subsequent 3Dimpingement simulation can help to detect posterior extraarticular ischiofemoral impingement. Acetabular morphology can be divided in anterior, lateral and posterior hip dysplasia. Combined osseous deformities are common, such as hip dysplasia combined with cam deformity (86%). Valgus deformities were reported in 44%. Combined hip dysplasia and increased femoral antetorsion can occur in 52%. Posterior extraarticular ischiofemoral impingement between the lesser trochanter and the ischial tuberosity can occur in patients with increased femoral antetorsion. Typically, labrum damage and hypertrophy, cartilage damage, subchondral cysts can occur in hip dysplasia. Hypertrophy of the muscle iliocapsularis is a sign for hip instability. Acetabular morphology and femoral deformities (cam deformity and femoral anteversion) should be evaluated before surgical therapy for patients with hip dysplasia, considering the different measurement techniques and normal values of femoral antetorsion.

Hip Joint Instability After Surgery Performed Through the Surgical Dislocation Approach.

Safe surgical dislocation of the hip is a versatile approach to the hip joint with a low complication rate. Hip joint instability is a devastating complication with poor prognosis. All hips treated surgically through the safe surgical dislocation approach were entered in a database and the complication of hip joint instability was studied prospectively from 2000 to 2021. Instability was diagnosed by intraoperative stress examination and on postoperative radiographs. The initial deformities treated, type of instability, presumed causes, treatment provided, response to the treatment, and final result were recorded as they happened during the course of the treatment. We considered patient's age, sex, body mass index (BMI), and initial diagnosis as risk factors. We evaluated the radiographs for femoral neck shortening, lack of greater trochanteric advancement, acetabular deformity, and incongruity of the hip joint. Anterior hip precautions were initiated in the middle of the study period. 22/459 hips developed hip joint instability after surgical dislocation approach performed for hip preservation. Acetabular deficiency, coxa breva, coxa valga, posterior impingement, increased anteversion, lax soft tissues, medial thigh obesity and lack of postoperative precautions seemed to contribute to instability. 50% of the hips became normal. Chondrolysis and residual subluxation were common in the others. Surgical dislocation approach disrupts the soft tissue restraints of the hip and joint stability depends on bony morphology, abductor muscle tension, and postoperative precautions. Several risk factors were subjective and speculative, but awareness of all the potential risk factors and prevention and treatment options should decrease this complication. IV Case series.

Limited External Rotation and Hip Extension Due to Posterior Extra-articular Ischiofemoral Hip Impingement in Female Patients With Increased Femoral Anteversion: Implications for Sports, Sexual, and Daily Activities

Background: Posterior femoroacetabular impingement (FAI) is poorly understood. Patients with increased femoral anteversion (FV) exhibit posterior hip pain. Purpose: To correlate hip impingement area with FV and with combined version and to investigate frequency of limited external rotation (ER) and hip extension (<40°, <20°, and <0°) due to posterior extra-articular ischiofemoral impingement. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Osseous patient-specific three-dimensional (3D) models based on 3D computed tomography scans were generated of 37 female patients (50 hips) with positive posterior impingement test (100%) and increased FV >35° (Murphy method). Surgery was performed in 50% of patients (mean age, 30 years; 100% female). FV and acetabular version (AV) were added to calculate combined version. Subgroups of patients (24 hips) with increased combined version >70° and patients (9 valgus hips) with increased combined version >50° were analyzed. The control group (20 hips) had normal FV, normal AV, and no valgus. Bone segmentation was performed to generate 3D models of every patient. Validated 3D collision detection software was used for simulation of impingement-free hip motion (equidistant method). Impingement area was evaluated in combined 20° of ER and 20° of extension. Results: Posterior extra-articular ischiofemoral impingement occurred between the ischium and the lesser trochanter in 92% of patients with FV >35° in combined 20° of ER and 20° of extension. Impingement area in combined 20° of ER and 20° of extension was larger with increasing FV and with higher combined version; correlation was significant (P < .001, r = 0.57, and r = 0.65). Impingement area was significantly (P = .001) larger (681 vs 296 mm2) for patients with combined version >70° (vs <70°, respectively) in combined 20° of ER and 20° of extension. All symptomatic patients with increased FV >35° (100%) had limited ER <40°, and most (88%) had limited extension <40°. The frequency of posterior intra- and extra-articular hip impingement of symptomatic patients (100% and 88%, respectively) was significantly (P < .001) higher compared with the control group (10% and 10%, respectively). The frequency of patients with increased FV >35° with limited extension <20° (70%) and patients with limited ER <20° (54%) was significantly (P < .001) higher compared with the control group (0% and 0%, respectively). The frequency of completely limited extension <0° (no extension) and ER <0° (no ER in extension) was significantly (P < .001) higher for valgus hips (44%) with combined version >50° compared with patients with FV >35° (0%). Conclusion: All patients with increased FV >35° had limited ER <40°, and most of them had limited extension <20° due to posterior intra- or extra-articular hip impingement. This is important for patient counselling, for physical therapy, and for planning of hip-preservation surgery (eg, hip arthroscopy). This finding has implications and could limit daily activities (long-stride walking), sexual activity, ballet dancing, and sports (eg, yoga or skiing), although not studied directly. Good correlation between impingement area and combined version supports evaluation of combined version in female patients with positive posterior impingement test or posterior hip pain.

CT-Based Calculation Model Assists Precise Treatment for Anterior and Posterior Ankle Bony Impingement.

Ankle arthroscope is the preferred tool for ankle surgeons to treat ankle impingement. However, there is no relevant report on how to improve the accuracy of arthroscopic osteotomy through preoperative planning. The aims of this study were to investigate a novel method to obtain the bone morphology in anterior and posterior ankle bony impingement through computed tomography (CT) calculation model, use this method to guide surgical decision-making, and compare the postoperative efficacy and actual bone cutting volume with conventional surgery. This retrospective cohort study includes 32 consecutive cases with anterior and posterior ankle bony impingement by arthroscopy from January 2017 to December 2019. Mimics software was utilized to calculate the bony morphology and measure the volume of the osteophytes by two trained software engineers. The patients were divided into the precise group (n=15) and the conventional group (n=17) according to whether obtain and quantify the osteophytes' morphology with CT based calculation model preoperative. All patients were evaluated clinically using visual analog scale (VAS) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, active dorsiflexion and plantarflexion angle before and after surgery at both 3 months and 12months postoperatively. We obtained the shape and volume of bone cutting through Boolean calculation. Clinical outcomes and radiological data were compared between the two groups. The VAS score, AOFAS score, active dorsiflexion angle and plantarflexion angle were significantly improved in both groups postoperatively. In comparison of the VAS score, AOFAS score, and active dorsiflexion angle, the precise group were higher than the conventional group in the follow-up at 3 and 12months postoperatively with statistical difference. The difference between the virtual bone cutting volume and the actual bone cutting volume of the anterior edge of distal tibia in the conventional group and precise group were 244.20 ± 147.66 mm3 and 76.53 ± 168.51 mm3 , respectively, there was statistical difference between the two groups (t=-2.927, p= 0.011). Using a novel method of obtaining and quantifying the bony morphology with CT-based calculation model for anterior and posterior ankle bony impingement can help guide surgical decision-making preoperatively and assist precise bone cutting during the operation, which can improve the efficacy and evaluate the accuracy of osteotomy postoperatively.

Defining Haglund’s deformity radiographically by incorporating the biomechanics of ankle motion

BackgroundHaglund’s deformity is clinically defined by the presence of retrocalcaneal tenderness, with previous radiographic parameters relying on calcaneal anatomic parameters that did not considering the influence of ankle motion on posterior calcaneal-Achilles impingement MethodsStanding foot radiographs from 55 patients with clinically defined Haglund’s deformity were compared to 50 control patients using previously described measurements and 2 new angular measurements based on the linkage between ankle rotation and posterior calcaneal-Achilles impingement. The ability of each measure to distinguish between Haglund’s and control patients was assessed. ResultsThe combination of the angles to account for both increased calcaneal tubercle height and increased posterior calcaneal prominence could distinguish between the two patient groups (p = .018, Area under the curve = 63.2%). None of the previously published radiographic criteria were different between the two patient groups. ConclusionsThe proposed radiographic criteria were more predictive than previous criteria that did not address the role of ankle motion.

Stripe Wear - Ceramic on Polyethylene Bearing Surface: A Case Report

Background: Stripe wear is a well-known phenomenon that might be caused by rim impingement, edge loading, metal particle entrapment, micro-separation, and transient subluxation. Stripe wear is felt to represent metal transfer and has been associated with squeaking in ceramic-on-ceramic bearings. In our paper, we report the presence of stripe wear on a retrieved modular ceramic femoral head from a patient with ceramic-on-polyethylene-bearing total hip arthroplasty. Method: We report a case of a 57-year-old male who originally had metal-on-metal (MOM) THA and underwent debridement and exchange of the bearing surface from MOM to ceramic-on-polyethylene (COP) articulation for pain and metallosis. He subsequently developed sepsis and underwent resection arthroplasty. Result: Intraoperatively, a cross-table lateral radiograph revealed the forward flexion of the acetabular component and femoral neck to posterior acetabular margin impingement. By analyzing the retrieved components macroscopically and microscopically, linear scars were found on the polyethylene liner, femoral neck, and femoral head in a pattern consistent with the X-ray finding. Conclusion: If metallosis is encountered after THA, the source of the metal wear should be identified. Component malposition is a possible cause, and the surgeon should consider revision or repositioning of the components if evidence of impingement is seen, as a simple bearing exchange may not solve the problem. This report indicates that stripe wear is not limited to ceramic on ceramic articulations.

Anterior and Posterior Ankle Arthroscopy in Prone Position: Description of Technique

Category: Arthroscopy; Ankle Introduction/Purpose: The ankle arthroscopy has many advantages compared to open surgery and it is possible to access the ankle anteriorly and posteriorly. The pathologies localized in the anterior and posterior aspects of the ankle may coexist and demand the combination of these approaches. The objective is to describe the anterior and posterior ankle arthroscopic access, keeping the patient in prone position, reducing the risks of contamination, surgical time and favoring the operative strategy. Methods: Patients diagnosed with chronic ankle instability and posterior ankle impingement, who failed conservative treatment for 3 months were selected. These patients were positioned in ventral decubitus and performed arthroscopic resection of posterior impingement followed by a Brostrom-Gould procedure, without decubitus change. Results: Patients were positioned in prone position, with spinal block performed and application of pneumatic tourniquet on the thigh. The posterior arthroscopic approach was first stablished through the posterolateral and posteromedial portals. The Os Trigonum could be identified and then removed. Maintaining the decubitus, the anterior approach was performed through 90° knee flexion, enabling the creation of the anteromedial and anterolateral portals. At this time, the lateral ankle instability could be treated by a Broström-Gould procedure in a upside down manner. Conclusion: The anterior and posterior approach by arthroscopy may provide a faster rehabilitation associated with lesser soft tissue trauma and lesser post-operative comorbities compared to open techniques. Also the combination of these approaches without decubitus change may reduce the surgery time and contamination risks. Disadvantages should also be considered and these includes the risk of compartimental syndrome and its severe complications. In addition, the arthroscopic images can be difficult to understand at first and the Broström-Gould procedure performed in a upside down manner will require a experienced staff in the surgery.