Intra-articular Lesions Research Articles

Development of a novel rabbit model for femoroacetabular impingement through surgically induced acetabular overcoverage.

There is a lack of validated small animal models for femoroacetabular impingement (FAI) that induce intra-articular lesions and cause osteoarthritis (OA) progression. The gene expression profile of articular cartilage in patients with FAI has not been characterized in animal studies. The purpose of this study is to describe a novel rabbit model for FAI with validated induction of intra-articular lesions and OA progression and to characterize the gene expression pattern in impinged cartilage using this model. Thirty 6-month-old New Zealand White rabbits underwent unilateral endobutton implant placement at the acetabular rim to surgically create overcoverage. Radiological assessment confirmed secure placement of endobutton at the acetabular rim for all operated hips with a mean alteration in lateral center-edge angle (ΔLCEA) of 16.2 ± 6.6°. Gross inspection revealed secondary cartilage injuries in the anterosuperior region of the femoral head for the operated hips. Cartilage injuries were shown to exacerbate with increased impingement duration, as demonstrated by the modified Outerbridge scores and Mankin scores. Immunostaining and quantitative real-time polymerase chain reaction revealed elevated expression of inflammatory, anabolic and catabolic genes in impinged cartilage. RNA sequencing analysis of cartilage tissue revealed a distinct transcriptome profile and identified C-KIT, CD86, and CD68 as central markers. Our study confirmed that the novel rabbit FAI model created acetabular overcoverage and produced articular cartilage injury at the impingement zone. Cartilage from the impingement zone demonstrated a heightened metabolic state, corroborating with the gene expression pattern observed in patients with FAI.

Predicting the Recovery of Isokinetic Knee Strength 6 Months After Anterior Cruciate Ligament Reconstruction.

The limb symmetry index (LSI) is a metric of strength restoration. It is key to successfully return to sports after anterior cruciate ligament (ACL) reconstruction. The threshold for return to sports is generally considered an LSI of ≥85%. To develop a statistical model for predicting the recovery of knee extension and flexion strength (with LSI ≥85%) at 6 months after ACL reconstruction. Case-control study; Level of evidence: 3. Patients who underwent arthroscopic ACL reconstruction between November 2015 and December 2020 were included. The patients were classified into 2 groups: "pass" if the LSI at 6 months postoperatively was ≥85% and "fail" if the LSI was <85%. Factors in 25 categories with 74 levels, including patient characteristics, periarticular procedures, intra-articular lesions and treatment, and perioperative management, were collected. A multivariable logistic regression combined with backward variable elimination was used to determine the predictive parameters for recovery of knee extension and flexion strength. A total of 948 patients were included. Graft site, preoperative isokinetic strength, treatment of meniscal injury, and injured side (left vs right) were identified as general predictors for both knee extension and flexion strength. For knee extension strength, age at injury and partial weightbearing duration were identified as additional predictors. For knee flexion strength, type of meniscal injury, surgeon volume, cartilage procedures, and periarticular procedures were identified as additional predictors. The Nagelkerke R 2 of the final model was 0.178, and the c-statistic was 0.716 (95% CI, 0.676-0.754). The Hosmer-Lemeshow test indicated good calibration (P = .879). Several factors including preoperative isokinetic strength, treatment of meniscal injuries, left vs. right side and graft site were found to predict recovery of ≥85% LSI in knee extension and flexion strength. Despite the numerous factors that were analyzed, the predictive power was moderate (c-statistic = 0.716), indicating there were other nonincluded factors that significantly influence strength performance at 6 months postoperatively.

Intra-articular Osteoid Osteomas: Imaging Manifestations and Mimics.

Osteoid osteoma (OO) is the third most prevalent benign bone neoplasm in children. Although it predominantly affects the diaphysis of long bones, OO can assume an intra-articular location in the epiphysis or the intracapsular portions of bones. The most common location of intra-articular OO is the hip joint. The presentation of intra-articular OOs often poses a diagnostic enigma, both from clinical and radiologic perspectives. Initial symptoms are often vague and nonspecific, characterized by joint pain, stiffness, and limited range of motion, which frequently contributes to a delayed diagnosis. Radiographic findings range from normal to a subtle sclerotic focus, which may or may not have a lucent nidus. In contrast to their extra-articular counterparts, intra-articular lesions have distinct features at MRI, including synovitis, joint effusion, and bone marrow edema-like signal intensity. While CT remains the standard for identifying the nidus, even CT may be inadequate in visualizing it in some cases, necessitating the use of bone scintigraphy or fluorine 18-labeled sodium fluoride PET/CT for definitive diagnosis. Radiologists frequently play a pivotal role in suggesting this diagnosis. However, familiarity with the unique imaging attributes of intra-articular OO is key to this endeavor. Awareness of these distinctive imaging findings of intra-articular OO is crucial for avoiding diagnostic delay, ensuring timely intervention, and preventing unnecessary procedures or surgeries resulting from a misdiagnosis. The authors highlight and illustrate the different manifestations of intra-articular OO as compared with the more common extra-articular lesions with respect to clinical presentation and imaging findings. ©RSNA, 2024 Supplemental material is available for this article.

E028 A differential diagnosis for treatment resistant psoriatic arthritis

Abstract Background/Aims This case involves a 45 year old gentleman with established psoriatic arthritis with axial and peripheral joint involvement. His disease was managed with subcutaneous methotrexate and etanercept. Despite improvement in axial symptoms and resolution of symptoms at other peripheral joints, he had ongoing severe monoarthritis of his right knee with significant pain and swelling. Methods In spite of several joint aspirations and intra-articular steroid injections [ten in total], escalation of dose of methotrexate, addition of sulfasalazine and switch of biologic to adalimumab, the patient’s right knee symptoms persisted. Further imaging was performed. An US scan showed chronic synovial hypertrophy with fatty metaplasia and an MRI scan showed frond like synovial thickening, suggestive of lipoma arborescens. Results The patient was referred to the orthopaedic surgeons and underwent excision synovectomy. The histopathology reported fibrofatty tissue with areas of chronic synovitis with presence of lymphoplasmacytic aggregates. The patient’s knee symptoms persisted for five years in total after clinical improvement at other joints; post-synovectomy, his right knee symptoms were improved. Lipoma arborescens is a benign progressive intra-articular lesion characterised by villous lipomatous proliferation of the synovium; it frequently affects the knee joint suprapatellar pouch. Villous proliferation of the synovium occurs, with subsequent replacement of synovial connective tissue by adipocytes. Conclusion Lipoma arborescens has been described occasionally in association with psoriatic arthritis. It is felt to occur as a reactive response to chronic synovial irritation; in this case from an inflammatory affront. Given the rarity of lipoma arborescens, coupled with the patient’s known underlying diagnosis of a seronegative arthritis, there was significant delay in his diagnosis. This case highlights the need to consider other causes of persistent joint pain and swelling when maximal therapeutic options have been unsuccessful. Disclosure A. Jacobs: None. M. Callan: None.

Intra-Articular Nodular Fasciitis of the Knee, A Rare Clinical Presentation and Histological Diagnosis: A Case Report.

Nodular fasciitis is a rare, benign soft tissue lesion that can prove to be difficult to diagnose, especially when intra-articular. A 17-year-old female softball player presents with several year history of right knee pain and swelling initially attributed to patellar maltracking refractory to non-operative and operative management. Initial pathology suggested tenosynovial giant cell tumor; however, further tissue diagnosis revealed nodular fasciitis, which was eventually resected. Intra-articular nodular fasciitis of the knee is rare and may easily be misdiagnosed due to its nonspecific clinical presentation. Careful histological examination can aid in diagnosis. Nodular fasciitis should be considered in the differential diagnoses for intra-articular lesions of the knee joint.

Exploring molecular mechanisms of intra-articular changes in osteonecrosis of femoral head using DIA proteomics and bioinformatics.

This study is aimed to delve into the crucial proteins associated with hormonal osteonecrosis of the femoral head (ONFH) and its intra-articular lesions through data-independent acquisition (DIA) proteomics and bioinformatics analysis. We randomly selected samples from eligible ONFH patients and collected samples from the necrotic area of the femoral head and load-bearing cartilage. The control group comprised specimens from the same location in patients with femoral neck fractures. With DIA proteomics, we quantitatively and qualitatively tested both groups and analyzed the differentially expressed proteins (DEPs) between groups. Additionally, we enriched the analysis of DEP functions using gene ontology terms and Kyoto Encyclopedia of Genes and Genomes pathways and verified the key proteins in ONFH through Western blot. Proteomics experiment uncovered 937 common DEPs (422 upregulated and 515 downregulated) between the two groups. These DEPs mainly participate in biological processes such as hidden attributes, catalytic activity, molecular function regulators, and structural molecule activity, and in pathways such as starch and sucrose metabolism, ECM-receptor interaction, PI3K-Akt signaling, complement and coagulation cascades, IL-17 signaling, phagosome, transcriptional misregulation in cancers, and focal adhesion. Through protein-protein interaction network target gene analysis and Western blot validation, we identified C3, MMP9, APOE, MPO, LCN2, ELANE, HPX, LTF, and THBS1 as key proteins in ONFH. With DIA proteomics and bioinformatics analysis, this study reveals the molecular mechanisms of intra-articular lesions in ONFH. A correlation in the necrotic area and load-bearing cartilage of ONFH at ARCO stages IIIB-IV as well as potential key regulatory proteins was identified. These findings will help more deeply understand the pathogenesis of ONFH and may provide important clues for seeking more effective treatment strategies.

Relationship between pain and intra-articular pathology in patients with chronic lateral ankle instability.

Repeated ankle sprains can lead to chronic lateral ankle instability (CLAI). It is unclear whether CLAI causes pain unless complicated by intra-articular lesions. This study aimed to analyze the characteristics of pain and the relationship between pain and intra-articular pathology in patients with CLAI. Fifty-three ankles in 46 patients with CLAI who had undergone surgery were retrospectively reviewed. The self-administered foot evaluation questionnaire (SAFE-Q) was given to patients the day before surgery. Intra-articular lesions were assessed using arthroscopy and magnetic resonance imaging (MRI). In addition, the Hounsfield Unit (HU) on computed tomography (CT) of the medial gutter was measured. The relationship between pain and intra-articular findings was also analyzed. The pain and pain-related scores in the SAFE-Q were significantly correlated with synovitis in 96.3% (rs = - 0.532). HU ratios in the tibia and talus were also significantly correlated with pain (rs = - 0.603, - 0.534, respectively). The arthroscopic synovitis score and HU ratios in patients with high pain scores were significantly higher than those in patients with low pain scores. Forty ankles (75.5%) had synovitis and articular cartilage injuries were observed in 22 ankles (41.5%). Patients with fluid collection or bone marrow lesions (BML) scored significantly lower in pain than those without, but there was no significant difference between patients with and without cartilage injury. Multiple regression analysis revealed that a high synovitis score and HU ratio of the talus were significantly associated with high pain. Intra-articular lesions such as synovitis and BML were associated with pain in patients with CLAI. Osteosclerotic changes in the medial gutter also induced ankle pain, indicating that osteoarthritic changes had already begun. Therefore, lateral ankle ligament injuries after ankle sprain should be appropriately treated to avoid secondary degenerative changes.

A Rare Cause of Recurrent Pain in Athletes: Synovial Hemangioma

Background: Synovial hemangioma is a rare neoplastic lesion, which can result in recurrent hemarthrosis and pain. It can affect any joint, tendon, or bursa, withal those around the knee. The intra-articular lesion is more prevalent and is more frequently diagnosed in female children or young adults. Indications: Surgery is indicated when patients present with recurrent painful hemarthrosis that affect daily living and functionality. Technique Description: Diagnostic knee arthroscopy, initially without tourniquet inflation, was performed to detect and study the extent of the lesion. Afterwards, the tourniquet was inflated to proceed with the surgical excision. Medial parapatellar approach was performed, and limits of the hemangioma were identified. Wide resection was performed taking care to not damage the medial meniscus and medial condyle cartilage. Neoplastic lesion was sent to pathology analysis. The tourniquet was deflated and hemostasis checked because these lesions can present extensive bleeding. Results: Localized, well-circumscribed, and encapsulated lesions have been reported to usually present low recurrence rate when completely excised. Discussion/Conclusion: It is a rare disease, and around 200 cases have been reported; therefore, conclusions about treatment and outcomes rely mostly on case series and case reports. Early diagnosis and treatment are paramount to prevent degenerative changes secondary to recurrent hemarthrosis. Patient Consent Disclosure Statement: The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Double posteromedial portals versus single posteromedial portal for arthroscopic management of popliteal cysts

BackgroundAs a common disease in orthopedic clinics, popliteal cysts often coexist with intra-articular lesions. Compared with traditional open surgery, arthroscopic treatment of popliteal cysts is less traumatic, and intra-articular lesions can be treated. The ‘one-way valve’ mechanism of the popliteal cyst can be removed by expanding the communication between the articular cavity and the cyst to avoid cyst recurrence. In terms of arthroscopic techniques, the comparison of clinical effects between the double posteromedial portal (DPP) and single posteromedial portal (SPP) has rarely been studied. The purpose of this retrospective study was to compare the clinical effects of DPP and SPP.MethodsA total of 46 consecutive patients with symptomatic popliteal cysts who underwent arthroscopic treatment were included in this study and followed for approximately 1 year. All patients were divided into two groups according to the arthroscopic portals (DPP group and SPP group). The cyst size, Lysholm score and Rauschening–Lindgren (R–L) grade were evaluated before the operation for all patients, and the intra-articular lesions, operative time and complications were recorded after operation. At the last follow-up, the Lysholm score and R–L grade were recorded, and magnetic resonance imaging was used to evaluate the outcome of the cyst. The clinical data of the two groups was statistically compared and analyzed.ResultsThere were no significant differences in preoperative cyst size, Lysholm score or R–L grade between the two groups (P > 0.05). The operation time of the DPP group (67.52 ± 18.23 min) was longer than that of the SPP group (55.95 ± 16.40 min) (P = 0.030), but the recurrence rate of cysts in the DPP group (0%) was obviously lower than that in the SPP group (19.0%) (P = 0.046). There were no significant differences in the Lysholm score, R–L grade or complication rate between the two groups at the last follow-up (P > 0.05).ConclusionArthroscopic treatment of popliteal cysts using double posteromedial portals was a safe and effective surgical method.Trial registration: ChiCTR, ChiCTR2200060115. Registered 19 May 2022, https://www.chictr.org.cn/showproj.html?proj=133199

Treatment of Intra-Articular Lesions After Posterior Inferior Tibiofibular Ligament Injury: A Case Series of Elite Rugby Players.

Surgical intervention is not typically used to treat symptoms after mild tibiofibular ligament injuries without ankle dislocation or subluxation. To describe outcomes in patients arthroscopically treated for unique intra-articular lesions after sustaining syndesmosis injury of the ankle. Case series; Level of evidence, 4. A total of 11 elite male rugby players with a mean age of 21.0 years (range, 17-28 years) were referred to our hospital for prolonged posterior ankle pain after a high ankle sprain during rugby football. The patients were examined using standing view radiography, computed tomography (CT) and magnetic resonance imaging (MRI) to determine the extent of ligament damage. Posterior ankle arthroscopy was performed to examine intra-articular lesions. The patients were evaluated using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle/hindfoot rating scale and sports activity score of the Self-Administered Foot Evaluation Questionnaire (SAFE-Q). The average reduced tibiofibular overlap on the standing mortise view was 1.2 mm (range, 0.5-2.0 mm) compared with the opposite ankles. Mason type 1 fracture was detected on CT in 6 patients, and ossification of the interosseous membrane was detected in 2 patients. A bone bruise in the posterior malleolus was observed on MRI in all but 1 patient. Intra-articular fragments located in the posterior ankle were observed and removed arthroscopically. Symptoms improved rapidly after arthroscopic treatment in all patients. All patients returned to rugby games at a median of 11 weeks postoperatively. The median AOFAS scores improved from 77 preoperatively to 100 postoperatively (P < .01), and the median SAFE-Q sports activity subscale score improved from 49.4 to 100 (P < .01). All unique intra-articular lesions that developed in rugby football players after syndesmosis injury were able to be treated arthroscopically. Patients returned to playing rugby football without syndesmosis reduction. Posterior ankle arthroscopy was effective in patients with residual symptoms after syndesmosis injury.

Technical Note: Tibial Spine Avulsion Treatment with Arthroscopic Reduction and Internal Fixation with Kirschner Wires in Skeletally Immature Patients.

Tibial spine avulsion injury, tibial eminence injury, tibial spine fracture, and anterior cruciate ligament (ACL) avulsion are multiple terms that express the same pathological condition. It can be encountered both in the pediatric and adult population. A wide array of surgical techniques have been proposed to manage displaced tibial spine avulsions. Anyway, insufficient evidence is currently available to prefer one fixation technique over another, and a gold-standard arthroscopy-based technique is still missing. In this article, we describe a mini-invasive, safe and user-friendly technique for arthroscopic reduction and internal fixation of displaced tibial eminence fractures. Standard and patient-specific accessory arthroscopic portals allow for full access to knee visualization and management of concomitant intraarticular lesions. After performing the debridement of the inflammatory tissue and the release of eventual interposed tissues in the fracture site, the tibial eminence avulsion can be reduced by using a less-invasive bone impactor. With the knee flexed to 90°, the fracture fragments are then synthesized (under fluoroscopic control) with three thin Kirschner wires inserted in a proximal-distal direction in a cross-shaped geometry. This technique allows a fast surgical and hospitalization time, a punctiform arthrotomy, proximal tibial physis preservation, and an early rehabilitation program. This novel technique seems attractive and very promising since it is respectful of the epiphyseal growth plates and is thus suitable for children and adolescents.

High prevalence of associated intra-articular injuries with increasing time period from anterior cruciate ligament injury to reconstruction, even in apparent copers

BackgroundIt still unclear whether copers may bear the same time-sensitive risk of intra-articular injury as non-copers. The objectives were to investigate the clinical characteristics of copers and non-copers that have sustained an anterior cruciate ligament (ACL) injury, and to examine and compare the intra-articular pathologies in delayed ACL reconstruction (ACLR) in copers and noncopers. MethodsPatients who sustained ACL injury while participating in high-performance sports and opted for non-operative treatment were enrolled in this study. Depending on the occurrence of the knee giving way, patients were classified into copers and noncopers. Clinical characteristics were compared between the two groups. Additionally, intra-articular injuries were evaluated for those who eventually underwent delayed ACLR. Results11 of the 75 patients (14.7%) were classified as copers. No major differences were found in the clinical characteristics between groups. Following the initial non-operative treatment, 67 patients underwent delayed ACLR. When examining intra-articular abrasions at the time of surgery, non-copers who continued sports activities for 3 to 12 months exhibited a significantly higher rate of injury as opposed to their coper counterparts. However, the difference in the prevalence of intra-articular lesions between the two groups in patients who continued to play sports for at least 12 months before surgery was nominal. ConclusionThe rate of copers was relatively low in patients who resumed playing high-level sports after ACL injury. Additionally, even in copers, those who continued sports activities for more than 12 months had comparably high prevalence of intra-articular injuries with noncopers. Study designRetrospective case-control study; Level of evidence, 3.

Clinical outcomes and cost-effectiveness of manipulation under brachial plexus block versus physiotherapy for refractory frozen shoulder: a prospective observational study

Frozen shoulder (FS) is a pathological condition that involves a painful and stiff shoulder joint, most commonly in people aged 40-60 years. Most literature supports treatment with physical therapy (PT), although some studies have demonstrated years of continuing pain and functional deficits. Manipulation under anesthesia is effective at eliminating the contracture of intra-articular lesions for refractory FS. This study aimed to compare whether manipulation under anesthesia or PT is a more effective treatment in refractory FS. This study was a prospective observational study. A total of 102 patients with refractory FS were enrolled in this study in the medical records, all of whom had severe and multidirectional loss of motion and thickening of the joint capsule and coracohumeral ligament on magnetic resonance imaging. Fifty-one patients were in the manipulation under brachial plexus block (MUB) group (34 females, median age: 57 years), and 51 patients were in the PT group (34 females, median age: 59 years). The MUB procedure consisted of the conventional method with additional adduction manipulation, in which one examiner initially abducted the shoulder joint as much as possible. We recorded the visual analog scale, shoulder range of motion, and American Shoulder and Elbow Surgeons and Constant Scores at the initial baseline visit and at the 1-, 3-, 6-, and 12-month follow-ups. The total cost was calculated from the medical records, and cost-effectiveness was evaluated using quality-adjusted life year and incremental cost-effectiveness ratio. Visual analog scale (P<.001), range of motion (P<.001), and American Shoulder and Elbow Surgeons and Constant Scores (P<.001) in the MUB group were significantly superior to those in the PT group at 1, 3, 6, and 12 months after treatment. The median cost and total quality-adjusted life year in the MUB and PT groups were $1375 versus $2751 and 2.95 versus 2.68, respectively, and the cost-effectiveness ratio between the MUB and PT groups was calculated as -$560. The new MUB procedure provides a shorter treatment period, better clinical outcomes, and higher cost-effectiveness in patients with refractory FS compared to PT.

Arthroscopically assisted internal fixation for treatment of acute ankle fracture: A systematic review and meta-analysis of comparative studies.

Arthroscopically assisted reduction and internal fixation (ARIF) allows for the assessment of joint congruity following anatomic reduction, identification of occult intra-articular lesions, and treatment of traumatic intra-articular pathologies. The aim of this systematic review and meta-analysis was to provide evidence on whether ARIF is an alternative treatment protocol for ankle fractures. The PubMed, Embase, and Cochrane Library databases were searched independently by two investigators from the inception dates to October 9, 2022, for comparative studies. The risk-of-bias tool of the Cochrane Collaboration for Randomized Controlled Trials and the methodological index for non-randomized studies (MINORS) were used for assessing the methodological quality. Outcomes were evaluated in terms of the Olerud-Molander Ankle Score (OMAS), American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scale, post-operative complications, arthroscopic findings, Visual Analogue Scale (VAS) score, and operation time. Cochrane Review Manager Software 5.4 was used to perform the statistical analysis. A total of 10 trials involving 755 patients were included in this meta-analysis. The results revealed that ARIF for ankle fractures was superior regarding functional outcomes and VAS scores when compared with open reduction and internal fixation (ORIF). No significant difference was noted in the post-operative complication rate and the operation time between the ARIF and ORIF groups. A high incidence of chondral or osteochondral lesions (OCLs), ligamentous injuries, and loose bodies with ankle fractures was found by ankle arthroscopy. ARIF for ankle fractures might be beneficial to offer superior functional outcomes and VAS score than ORIF. Orthopedic surgeons should take a high incidence of OCLs and ligamentous injuries into consideration for the treatment of acute ankle fractures. We believe that with the increase in surgical experience, the occurrence of post-operative complications and the extension of operation time will no longer be a potential concern for surgeons.

Facteurs de risque de persistance d’un kyste poplité résiduel après décompression arthroscopique et kystectomie : association avec des lésions cartilagineuses dégénératives

BackgroundIn previous studies, good results have been reported after arthroscopic treatment of popliteal cysts and concomitant intra-articular pathology. However, only a few studies have reported the associated factors with residual popliteal cysts. The aim of this study was to examine the clinical and radiographic outcomes and investigate the factors associated with the recurrence of popliteal cyst after arthroscopic cyst decompression and cyst wall resection. HypothesisThe authors hypothesized that residual popliteal cyst after arthroscopic decompression and cystectomy would be associated with degenerative cartilage lesions. Patients and methodsFrom December 2010 to December 2018, 54 patients with popliteal cysts were treated with arthroscopic decompression and cyst wall resection through an additional posteromedial cystic portal. Magnetic resonance imaging (MRI) or ultrasonography was used to observe whether the popliteal cyst had disappeared or decreased. The maximum diameter of the popliteal cyst was measured after surgery. The patients were classified into the disappeared and reduced groups according to the treatment outcome. Age, sex, symptom duration, preoperative degenerative changes based on the Kellgren–Lawrence (K-L) grade, cartilage lesions according to the International Cartilage Repair Society (ICRS) grades, synovitis, functional outcomes, and associated intra-articular lesions were compared between the two groups. The functional outcome was evaluated on the basis of the Rauschning and Lindgren knee score. The study included 22 men and 32 women, with mean age of 49.6years (range: 5–82years). According to the ICRS grade system, 28 (51.8%) patients had grade 0 to II, 26 (48.2%) patients had grade III to IV. ResultsFollow-up radiographic evaluation revealed that the cyst had completely disappeared in 20 patients (37%) and reduced in size in 34 (63%). The mean cyst size was decreased significantly from 5.7cm (range: 1.7–15cm) to 1.7cm (range: 0–6.4cm), and the Rauschning and Lindgren knee score showed improved clinical features in all the patients. Between the disappeared and reduced groups, the presence of degenerative cartilage lesions (p=0.022, odds ratio 8.702, 95% confidence interval: 1.368–55.362) showed a statistically significant differences. DiscussionThrough the posteromedial cystic portal, cysts were completely removed in approximately 40% of patients, and the size was reduced in 60% of patients. Presence of degenerative cartilage lesion represents an associated risk factor for residual popliteal cyst. These findings could be helpful in ensuring explaining poor prognostic factors. Level of evidenceIIIb; retrospective cohort study.

Synovial Lipomatosis: Histopathologic Features in a Series of Five Cases.

Synovial lipomatosis is a controversial entity of uncommon intraarticular joint lesions. Most studies focused on radiological findings and surgical resection modalities. Pathologic findings were limited to case reports. Detailed descriptions of the histopathologic features are lacking. We aim to highlight the salient histopathologic features of synovial lipomatosis. We performed a retrospective review study over 15 years retrieving cases of synovial lipomatosis. We found 5 patients (age range: 8-78, average age: 50 years, male to female ratio: 4:1) demonstrating unilateral synovial lipomatosis out of 241 (2.0%) patients with knee joint lesions. Four patients had osteoarthritis. One patient was obese. The resected specimens showed synovial hyperplasia, surface fibrin, hemosiderin pigment, microcalcifications, lymphoplasmacytic infiltrates, lymphoid aggregates, stromal fibrotic, degenerative, and metaplastic alterations shared by other synovitis related changes. Consistent features included abundant adipocytic components, surface adipocytes, prominent large vessel vasculatures, plasma cells, and dense perivascular lymphocytic cuff-like infiltrates. One patient demonstrated superimposed sarcoid-type epithelioid granulomas. A distinct fibrous band separated the lesional tissue from the underlying normal fatty tissue. Synovial lipomatosis predominates in older males with degenerative joint conditions with a second peak in children and adolescents. Obesity is not a risk factor. Some histopathologic features help distinguish synovial lipomatosis from look-alike joint lesions. The findings may suggest an angiolipomatous hamartomatous growth or an exaggerated synovial reaction inducing florid subsynovial stromal proliferative, metaplastic, and degenerative changes. Regardless of its etiopathogenesis, pathologists have a role in confirming the diagnosis and ensuring a complete arthroscopic synovectomy by assessing the presence of the fibrous septa.

Poster 175: ALPSA Lesions Associated with High Rate of Early Repair Failure

Objectives: Anterior labroligamentous periosteal sleeve avulsion (ALPSA) lesions occur in patients with recurrent shoulder instability and are associated with higher rates of failure after capsulolabral repair surgery compared to typical Bankart lesions. Despite recognition that these lesions can portend poor outcomes, there is relatively limited data to understand the associated injuries and postoperative course in a young, active population. The purpose of this study is to evaluate ALPSA lesions for associated pathology and outcomes. Methods: Methods: We reviewed the records of 312 patients who underwent arthroscopic shoulder stabilization by one of two fellowship trained sports surgeons at a single facility between 1 January 2010 and 31 December 2015. Inclusion criteria were a minimum follow-up of five years after index surgical repair and presence of an ALPSA lesion as identified on arthroscopic exam, leaving 46 patients available for review. Our primary outcome measures were failure and operative revision surgery. We considered failure as any recurrent shoulder instability events including subjective subluxation and dislocation, recurrence of pain consistent with instability, or functionally limiting apprehension. We performed survival analysis and a multivariate logistic regression analysis to identify factors associated with failure. Results: Results: In total, 46 patients with average age 21.2 years met inclusion and underwent surgery a median of 7.1 months after initial recalled injury event. 11/46 had concomitant posterior pathology in addition to anterior labral lesion. Six patients were found to have SLAP lesions. All patients experienced subjective instability, and 44/46 endorsed pain prior to surgery. 38/46 reported having experienced complete dislocation. The median number of dislocations before surgery was 3. Repairs were performed with average 3.7 anchors. Eight patients failed surgery at median 15.1 months post-index procedure, with 75% of failures occurring before two years with the remaining 25% occurring later in follow-up. Three of these failed revision repair. Conclusions: Conclusions: ALPSA lesions frequently occur in the presence of other intra-articular shoulder lesions and portend a high rate of recurrent shoulder instability despite repair. Notably, while failure occurs at a high rate, most repair failure for these lesions tends to occur early.

Arthroscopically Assisted Suprapatellar Tibial Nail Removal

Intramedullary nailing remains the most popular and preferred method of fixation for tibial shaft fractures. The infrapatellar approach through the patellar tendon has long been considered the gold standard. However, the suprapatellar approach has gained popularity because of the advantages of being easier to perform when treating proximal shaft and metaphyseal fractures and there being less postoperative anterior knee pain. Despite increased use of this approach, the removal of the implant from the same suprapatellar approach is tricky, and in most cases, the removal is performed through a new transpatellar tendon approach. This article describes arthroscopically assisted suprapatellar tibial nail removal using the same approach and instrumentation of the nail insertion. The technique has the advantage of preserving the patellar tendon without causing secondary damage to it. Through arthroscopy, direct visualization of the patellofemoral joint aids in preventing possible cartilage injury. Moreover, any associated intra-articular lesions can be diagnosed and addressed.

Predictive value of ultrasound-guided anesthesia injection in arthroscopy for borderline developmental dysplasia of the hip

Objective: To evaluate the value of ultrasound-guided intra-articular anesthetic injection in predicting postoperative outcomes for borderline developmental hip dysplasia (BDDH). Methods: A follow-up study. The clinical data of 37 BDDH patients who received ultrasound-guided intra-articular anesthetic injection and arthroscopic examination in the Department of Sports Medicine, Senior Department of Orthopedics, the Fourth Medical Center of PLA General Hospital from May 2018 to February 2021 were retrospectively analyzed. Among them, there were 17 males and 20 females with a mean age of (37.9±12.8) years. All patients underwent ultrasound-guided intra-articular anesthetic injection prior to arthroscopy, and were evaluated with hip physical examination before and after injection, as well as before and after arthroscopy, in order to obtain the visual analog score (VAS) of pain for seven assessments. The total VAS score was calculated based on these evaluations. Follow-up was conducted for at least 12 months. The effective rate of injection referred to the ratio of the improvement of VAS score after anesthetic injection to the total VAS score before injection. Pearson correlation analysis and Bland-Altman analysis were used to test the correlation between modified Harris hip score (mHHS) after ultrasound-guided intra-articular anesthetic injection and mHHS score after arthroscopic surgery. A binary logistic regression model was established to analyze the substantial clinical benefit (SCB) for patients. Following the logistic regression analysis, a receiver operating characteristic (ROC) curve was constructed to evaluate the predictive power of ultrasound-guided intra-articular anesthetic injection in achieving SCB in those patients. The optimal cut-off value for injection efficacy was determined based on the ROC curve when SCB was achieved. Results: The follow-up time for all patients was (26.3±7.6) months. After anesthetic injection for 20 minutes, the total VAS score of pain [M(Q1,Q3)] decreased from 13(8,23) points before injection to 1(0,4) points; and the mHHS score [M(Q1,Q3)] increased from 60(46,70) points before arthroscopy to 90(84,96) points after, with statistically significant differences before and after injection and before and after arthroscopy (both P<0.001). Pearson correlation analysis showed that the mHHS score after intra-articular anesthetic injection was positively correlated with the mHHS score after surgery (r=0.961, P<0.001). The area under the ROC curve for predicting SCB after arthroscopy with ultrasound-guided intra-articular anesthetic injection was 0.769 (95%CI: 0.561-0.976), the Youden index was 0.663, the cut-off value was 0.569 2, the sensitivity was 96.3%, and the specificity was 70.0%. Conclusions: The results of ultrasound-guided intra-articular anesthetic injection before arthroscopy can indicate the presence of intra-articular lesions, and the degree of pain relief after injection is proportional to the functional recovery after arthroscopy. Patients with intra-articular anesthetic injection efficacy>56.92% have better results in hip arthroscopy.

Comparison of Arthroscopic-Assisted Percutaneous Internal Fixation With a Modified Reducer Versus Open Reduction and Internal Fixation for Schatzker Type II and III Tibial Plateau Fractures.

Tibial plateau fractures require anatomical reduction and stable fixation to achieve satisfactory results. In addition, addressing any related injuries is of paramount importance. Arthroscopic reduction and internal fixation (ARIF) has been promoted as a possible technique to treat tibial plateau fractures. To compare the effectiveness of ARIF with this modified reducer and open reduction and internal fixation (ORIF) for Schatzker types II and III tibial plateau fractures. Cohort study; Level of evidence, 3. We retrospectively reviewed 68 patients who were treated for Schatzker type II or III tibial plateau fractures between August 1, 2014, and October 31, 2018. Patients were categorized into the ARIF (n = 33) and ORIF groups (n = 35). The groups were compared regarding intra-articular injuries, duration of hospital stay, complications, and clinical outcomes-including the International Knee Documentation Committee (IKDC) score, the Hospital for Special Surgery (HSS) score, and range of motion (ROM). The paired t test was used to compare preoperative and postoperative data, and the chi-square test was used to compare the IKDC and HSS scores. The median follow-up period was 36 months (26-40 months). Additional intra-articular lesions were found in 29 patients-21 in the ARIF group and 8 in the ORIF group (P = .02). A significant difference was observed in the duration of hospital stay-3.58 ± 1.46 days for the ARIF group and 4.57 ± 1.12 days for the ORIF group (t = -3.169; P = .002). All fractures healed within 3 months after surgery. The complication rate for all patients was 11%, with no significant difference between the ARIF and ORIF groups (t = 1.244; P = .265). At the final follow-up, there were no significant differences between the 2 groups in the IKDC score, HSS score, and ROM (P > .05 for all). ARIF with a modified reducer was found to be an effective, reliable, and safe procedure for the treatment of Schatzker types II and III tibial plateau fractures. Both ARIF and ORIF provided equally good results, while ARIF offered a more precise evaluation and reduced the duration of hospital stay.