Loose Body in the Knee Joint: A Case Report

Background: Loose bodies (LBs) within the knee joint are commonly encountered during clinical practice and are frequently observed during knee arthroscopy. The primary treatment involves the removal of loose bodies;however, their complete eradication is often challenging and may not address underlying diseases, leading to persistent symptoms and the risk of new loose body formation. Aim: This case report aims to present the findings and surgical management of a 52-year-old male with an unusually large osseous loose body in the knee joint and associated pathologies. Case Presentation: The patient, a 52-year-old male, experienced recurrent episodes of severe, sudden, and painful locking of the knee joint, leading to difficulties moving. A plain MRI study was conducted to evaluate the condition of the knee joint, which revealed various degenerative changes and the presence of a loose body. Subsequently, an arthroscopic examination was performed under general anesthesia, uncovering the presence of an abnormally large loose body, as well as other pathologies including chondropathy, meniscal degeneration, and Baker’s cyst. Conclusion: Loose bodies (LBs) in the knee joint pose significant challenges and may lead to debilitating symptoms. Timely diagnosis and appropriate surgical intervention are crucial for symptom relief and the prevention of further joint damage as arthroscopic excision. Comprehensive imaging has a vital role in guiding treatment decisions and optimizing patient outcomes. In this case, the removal of the loose body improved patient outcomes and helped prevent potential joint complications.

The Immediate Analgesic Effect and Impact on Gait Function of Transcutaneous Electrical Nerve Stimulation in Late-Stage Elderly Individuals with Knee Pain: Examination of Gait Function Using an IoT-Based Gait Analysis Device

Purpose: This study verified the effects of transcutaneous electrical nerve stimulation (TENS), which can be worn during walking and exercise, in elderly individuals with late-stage knee pain who exercise regularly. Methods: Thirty-two late-stage elderly individuals were evaluated for knee pain during rest, walking, and program exercises, with and without TENS. Gait analysis was performed using an IoT-based gait analysis device to examine the effects of TENS-induced analgesia on gait. Results: TENS significantly reduced knee pain during rest, walking, and programmed exercises, with the greatest analgesic effect observed during walking. The greater the knee pain without TENS, the more significant the analgesic effect of TENS. A comparison of gait parameters revealed a significant difference only in the gait cycle time, with a trend towards faster walking with TENS;however, the effect was limited. Conclusion: TENS effectively relieves knee pain in late-stage elderly individuals and can be safely applied during exercise. Pain management using TENS provides important insights into the implementation of exercise therapy in this age group.

Biomechanical research of knee joint during the process of running

To study the effect of speed on the biomechanics of a knee joint during running, a biomechanical model of human lower limb joints is established based on the Kane method and semi-physical simulation. Experiments on the running process were made at different speeds for healthy young men. The influence of running speed on knee Joint motion is analyzed quantitatively and a mathematical model of the knee angle is established with speed as the independent variable. Results show that, at the moment of the heel contacting with theground, with the increase of speed, the more, and the calf and thigh are closer to the same line. In the middle stage of a gait cycle, the thigh stretches back, and then the calf and thigh are close to collineation. At that moment, the stretch of the posterior cruciate ligament is the largest, and the slower the speed, the more obvious the collineation. The maximal joint angle of the calf relative to the thigh appears in the later stage, and themaximal joint angle increases with the increase of the velocity. With the increase of the running speed, the phase of the cure of knee angle moves forward. The results can be used in the field of rehabilitation robotics and humanoid robot.

The Knee Joint Design and Control of Above-knee Intelligent Bionic Leg Based on Magneto-rheological Damper

The above-knee intelligent bionic leg is very helpful to amputees in the area of rehabilitation medicine. This paper first introduces the functional demand of the above-knee prosthesis design. Then, the advantages of the four-bar link mechanism and the magneto-rheological （MR） damper are analyzed in detail. The fixed position of the MR damper is optimized and a virtual prototype of knee joint is given. In the end, the system model of kinematics, dynamics, and controller are given and a control experiment is performed. The control experiment indicates that the intelligent bionic leg with multi-axis knee is able to realize gait tracking of the amputee＇s healthy leg based on semi-active control of the MR damper.

Dynamic knee valgus kinematics and their relationship to pain in women with patellofemoral pain compared to women with chronic hip joint pain

Background:Dynamic knee valgus(DKV)is an abnormal movement pattern visually characterized by excessive medial movement of the lower extremity during weight bearing.Differences in hip and knee kinematic components of DKV may explain the emergence of different pain problems in people who exhibit the same observed movement impairment.Using a secondary analysis of exiting data sets,we sought to determine whether hip and knee frontal and transverse plane angles during a functional task differed between women with patellofemoral pain and women with chronic hip joint pain and the relationship between joint-specific kinematics and pain in these 2 pain populations.Methods:In the original studies,3-dimensional hip and knee kinematics during a single-limb squat were obtained in 20 women with patellofemoral pain and 14 women with chronic hip joint pain who demonstrated visually classified DKV.Pain intensity during the squat was assessed in both groups.For the secondary analysis,kinematic data were compared between pain groups using their respective control groups as a reference.Within each pain group,correlation coefficients were used to determine the relationship between kinematics and pain during the squat.Results:Hip adduction and contralateral pelvic drop were greater in those with chronic hip joint pain compared to those with patellofemoral pain(effect sizes ≥0.40).Greater knee external rotation(r= 0.47,p= 0.04)was correlated with greater knee pain in those with patellofemoral pain,while greater hip adduction(r = 0.53,p = 0.05)and greater hip internal rotation(r = 0.55,p = 0.04)were correlated with greater hip pain in those with chronic hip joint pain.Conclusion:Hip frontal plane motion was greater in those with chronic hip joint pain compared to those with patellofemoral pain.In both groups,greater abnormal movement at the respective joint(e.g.,knee external rotation in the patellofemoral pain group and hip adduction and internal rotation in the chronic hip joint pain group)was associated with greater pain at that joint during a single-limb squat.

Two-stage revision arthroplasty for coagulase-negative staphylococcal periprosthetic joint infection of the hip and knee

BACKGROUND Periprosthetic joint infections(PJIs)are frequently caused by coagulase-negative Staphylococci(CoNS),which is known to be a hard-to-treat microorganism.Antibiotic resistance among causative pathogens of PJI is increasing.Two-stage revision is the favoured treatment for chronic CoNS infection of a hip or knee prosthesis.We hypothesised that the infection eradication rate of our treatment protocol for two-stage revision surgery for CoNS PJI of the hip and knee would be comparable to eradication rates described in the literature.AIM To evaluate the infection eradication rate of two-stage revision arthroplasty for PJI caused by CoNS.METHODS All patients treated with two-stage revision of a hip or knee prosthesis were retrospectively included.Patients with CoNS infection were included in the study,including polymicrobial cases.Primary outcome was infection eradication at final follow-up.RESULTS Forty-four patients were included in the study.Twenty-nine patients were treated for PJI of the hip and fifteen for PJI of the knee.At final follow-up after a mean of 37 mo,recurrent or persistent infection was present in eleven patients.CONCLUSION PJI with CoNS can be a difficult to treat infection due to increasing antibiotic resistance.Infection eradication rate of 70%-80%may be achieved.

Risk of methicillin-resistant staphylococcus aureus prosthetic joint infection in elective total hip and knee arthroplasty following eradication therapy

BACKGROUND Prosthetic joint infection(PJI)is a devastating complication requiring prolonged treatment and multiple operations,leading to significant morbidity for the patient.Patients are routinely tested for methicillin-resistant staphylococcus aureus(MRSA)colonisation.MRSA positive patients are given eradication therapy.We hypothesise that patients who are MRSA positive pre-operatively,have increased risk of developing PJI.AIM To identify deep wound infection(PJI)rates in patients who are colonised MRSA positive compared with those who are not colonised;and long term clinical and radiological outcomes.METHODS All patients who underwent total hip and knee replacements(THR/TKR)between December 2009 and December 2019 were identified.Patients who were also identified as being MRSA positive at pre-operative assessment were then selected.Confirmation of prescribing eradication treatment was recorded.Patient records,including consultation letters,operation notes and microbiology results were reviewed retrospectively.Comparison of outcomes for each MRSA positive patient was made with 2 MRSA negative patients undergoing the same operation of a similar age by the same consultant.RESULTS Screening identified 42 knee and 32 hip arthroplasty patients as MRSA positive,84 MRSA negative knee and 64 hip patients were reviewed.Patients were matched with medical co-morbidities in each group.Mean follow up was 5 years.PJI was identified in 4/32(12.5%)of THR MRSA positive and 3/42(7%)of TKR patients.All patients had PJI within one year of surgery.CONCLUSION MRSA positive patients are given eradication therapy routinely.However,no confirmation of eradication is sought.Patients who have MRSA colonisation preoperatively,in our study had a significantly increased risk of PJI,when compared to negative patients.We would recommend establishing true eradication after treatment prior to arthroplasty.

Evaluating the effects of pain and disorders of the knee joint on knee extension strength and daily life activities in the female elderly

This study aimed at examining the differences in leg strength and activities of daily living (ADL) ability among groups with various knee problems. The subjects consisted of 328 elderly females who were classified into three groups: those without knee pain or a knee disorder, those with knee pain, and those with a knee disorder. The subjects took a knee extension strength test and an ADL survey. Knee extension strength and ADL scores (total score and each domain score of the motions of locomotion, posture change, stability, and manipulation) were selected as the evaluation parameters. The knee extension strength, total ADL score and each domain score of the motions of locomotion, posture change, and stability ranged from low to high in the following order: the group with a knee disorder, the group with knee pain, and the group without pain or a knee disorder. Moreover, manipulation scores were significantly inferior in the group with a knee disorder compared with the other two groups. In conclusion, the female elderly with knee pain or a knee disorder have inferior knee extension strength and ADL with respect to the motions of locomotion, posture change and stability. In addition, with regard toknee extension strength with respect to theabove three motions, the elderly with a knee disorder have inferior scores when compared with the elderly who have only knee pain;thus, they find it difficult to perform activities involving the knee joints.

The Relationship between Incorrect Restoration of the Joint Line and Lateral Knee Pain in Patients Undergoing Total Knee Arthroplasty

Aim: In this study, the relationship between the change in the joint line and lateral knee pain was evaluated after primary total knee arthroplasty. Material and method: Between 2005 and 2012, patients who underwent primary total knee arthroplasty were included in the study. Patients having “cruciate retaining total knee arthroplasty” and with a change of the joint line ≥8 mm and patients having “posterior stabilized total knee arthroplasty” and with a change of the joint line ≥5 mm were selected as the study group (group 1, n = 32). A total of 47 patients having similar demographic characteristics with the study group and the joint line changing below the predetermined level or remaining unchanged were included as the control group (group 2). The 2 groups were compared according to the presence of knee pain, the localization and spread of the pain, iliotibial band, tension and pain in the patellar tendon and quadriceps tendon, front knee pain during squatting, VAS pain score, OBER test positivity, Knee Society knee and function score, and general patient satisfaction. Results: There were statistically significant more lateral knee pain (p < 0.001), OBER test positivity (p < 0.001) and iliotibial band tension (p < 0.001) in group 1 compared to group 2. However, there were no statistically significant differences between the 2 groups regarding rest pain (p = 0.855), pain during squatting (p = 0.761), exertional pain (p = 0.322), pain in the patellar tendon (p = 0.643) and quadriceps tendon (p = 0.873), Knee Society knee (p = 0.954) and function (p = 0.955) scores, and general satisfaction (p = 0.968). Conclusion: In total knee prosthesis operations, distal displacement of the joint line can result in lateral knee pain and iliotibial band tension. However, considering the results of total knee arthroplasty our findings have showed that this condition has no effect on knee functions and patient satisfaction.

Metastatic Rectal Adenocarcinoma of the Hip and Knee Joints: A Case Series

Two cases are presented of patients with a history of metastatic rectal adenocarcinoma presenting with a painful joint effusion. Both cases are potential examples of metastasis to periarticular bone with local infiltration to the synovium, which is one proposed mechanism of intrasynovial metastasis. While skeletal metastases are a relatively common occurrence in metastatic adenocarcinoma, intraarticular metastasis is extremely rare. These cases highlight the need to consider metastasis in the differential of joint swelling in the setting of a history of adenocarcinoma.

Prosthetic joint infection of the hip and knee due to Mycobacterium species:A systematic review

BACKGROUND Mycobacterium species(Mycobacterium sp)is an emerging cause of hip and knee prosthetic joint infection(PJI),and different species of this organism may be responsible for the same.AIM To evaluate the profile of hip and knee Mycobacterium PJI cases as published in the past 30 years.METHODS A literature search was performed in PubMed using the MeSH terms“Prosthesis joint infection”AND“Mycobacterium”for studies with publication dates from January 1,1990,to May 30,2021.To avoid missing any study,another search was performed with the terms“Arthroplasty infection”AND“Mycobacterium”in the same period as the previous search.The Preferred Reporting Items for Systematic Reviews and Meta-Analyses chart was used to evaluate the included studies for further review.In total,51 studies were included for further evaluation of thecases,type of pathogen,and treatment of PJI caused by Mycobacterium sp.RESULTS Seventeen identified Mycobacterium sp were reportedly responsible for hip/knee PJI in 115 hip/knee PJI cases,whereas in two cases there was no mention of any specific Mycobacterium sp.Mycobacterium tuberculosis(M.tuberculosis)was detected in 50/115(43.3%)of the cases.Nontuberculous mycobacteria(NTM)included M.fortuitum(26/115,22.6%),M.abscessus(10/115,8.6%),M.chelonae(8/115,6.9%),and M.bovis(8/115,6.9%).Majority of the cases(82/114,71.9%)had an onset of infection>3 mo after the index surgery,while in 24.6%(28/114)the disease had an onset in≤3 mo.Incidental intraoperative PJI diagnosis was made in 4 cases(3.5%).Overall,prosthesis removal was needed in 77.8%(84/108)of the cases to treat the infection.Overall infection rate was controlled in 88/102(86.3%)patients with Mycobacterium PJI.Persistent infection occurred in 10/108(9.8%)patients,while 4/108(3.9%)patients died due to the infection.CONCLUSION At least 17 Mycobacterium sp can be responsible for hip/knee PJI.Although M.tuberculosis is the most common causal pathogen,NTM should be considered as an emerging cause of hip/knee PJI.

Anatomy of the anterolateral ligament of the knee joint

Despite remarkable improvements in clinical outcomes after anterior cruciate ligament reconstruction,the residual rotational instability of knee joints remains a major concern.The anterolateral ligament(ALL)has recently gained attention as a distinct ligamentous structure on the anterolateral aspect of the knee joint.Numerous studies investigated the anatomy,function,and biomechanics of ALL to establish its potential role as a stabilizer for anterolateral rotational instability.However,controversies regarding its existence,prevalence,and femoral and tibial insertions need to be addressed.According to a recent consensus,ALL exists as a distinct ligamentous structure on the anterolateral aspect of the knee joint,with some anatomic variations.The aim of this article was to review the updated anatomy of ALL and present the most accepted findings among the existing controversies.Generally,ALL originates slightly proximal and posterior to the lateral epicondyle of the distal femur and has an anteroinferior course toward the tibial insertion between the tip of the fibular head and Gerdy’s tubercle below the lateral tibial plateau.

The Establishment of Three-Dimensional Model of Human Knee Joint

Objective: To discuss a method to establish a three-dimensional model of healthy human knee joint, which can be used for further knee joint biomechanics analysis and simulation. Methods: CT scan and medical image three-dimensional reconstruction software (Mimics) were used to obtain the knee joint three-dimensional finite element model (FEM) according to reverse engineering theory. Results: FEM of knee joint with complete bone structure was established by Mimics. Conclusion: Three-dimensional FEM was established according to CT images exports as IGES file. The model can be used for knee joint biomechanics finite element analysis to provide references and proposals for the clinical diagnoses of knee joint illness, and the design of artificial knee joint prosthesis.

A Case Report of Synovial Osteochondromatosis of the Knee Joint with neither Calcification nor a Synovial Lesion on Imaging

Synovial osteochondromatosis is a rare, benign condition of unknown etiology in which the synovium undergoes metaplasia, leading to cartilaginous nodules that ultimately break free, mineralize, and even ossify. The most commonly involved joint is the knee. Typically, radiographs can be diagnostic and mineralized nodules are pathognomonic. In as many as one-third of cases, however, no calcification or ossification of the cartilage occurs in the early stage of the disease because mineralization is time-dependent. In such cases, gadolinium-enhanced MRI can be useful. Unmineralized nodules are typically peripherally enhanced because they are attached to and derive a vascular supply from the synovium. We experienced an unmineralized case of synovial osteochondromatosis of the right knee joint, in which imaging diagnosis was difficult. Neither calcification nor ossification was observed, but all nodules were released from the synovium as loose bodies and there was no vascular supply. Therefore, MRI did not show a typical appearance. These findings suggest that synovial osteochondromatosis should be considered as a differential diagnosis in a case in which unmineralized loose bodies without a synovial lesion are found in an imaging examination.

IL-1B,IL-6 and TNF-a change of experimental knee joint degeneration model and effect of local loosening therapy

Objective To observe IL-1B,IL-6 and TNF-a level change of the joint fluid in the experimental knee joint degeneration and the effect of the local loosening therapy.Methods Thirty rabbits were divided into 3 groups at random:ten in the normal contrast group,ten in the blank model group and ten in the loosening therapy group to observe the IL-1B,IL-6 and TNF-a change of the joint fluid before and after the treatment in each group.Result IL-1B,IL-6 and TNF-a level in the blank model group was obviously higher than that in the normal group.(P<0.05).IL-1B,IL-6 and TNF-a level in the treatment group was obviously lower than that in the normal group.(P<0.05).Conclusions 1)IL-1B,IL-6 and TNF-a level of the joint fluid in the blank model group was obviously higher than that in the normal group.2)Loosening soft tissues of the knees can improve IL-1B,IL-6 and TNF-a level of the joint fluid.

Application of X-ray digital tomosynthesis in knee joint trauma examination

Objective: To explore the clinical value of X-ray digital tomosynthesis(DTS)in the diagnosis of knee joint fractures. Methods: A total of 28 cases of thoracic trauma, X-ray film cannot be clearly diagnosed or can confirm the diagnosis but the need for further identification of forensic diagnosis of cases of DTS scan and three-dimensional reconstruction in order to control the study. Results: 1. The reconstructed images after DTS scanning showed that the knee joint fractures were clearly diagnosed, and the detection rate of 28 knee joint fractures was 92.86%. 2. DTS scanning could clearly detect the fresh knee joint fracture's fracture line, corresponding line and broken bones. For the old fracture, DTS scanning could clearly show the condition of the fracture end's healing. Conclusions: The technique is of great value in the diagnosis of knee joint fracture, especially in the examination of complex structure, thick body and review of internal fixation after fracture.

Clinical effect of sodium hyaluronate joint cavity filling combined with exercise therapy on patients with post-traumatic knee arthritis

Objective:To research the sodium hyaluronate joint cavity filling combined with exercise therapy on the indicator of pain,motor function,and levels of inflammatory factors in joint fluid in patients with post-traumatic knee arthritis.Method Totally 100 patients(Department of Orthopaedics,The second Affiliated Hospital to Liaoning University of Chinese Medicine,2013.10-2018.8)with post-traumatic knee arthritis were selected,then they were divided into observation group(n=50)and control group(n=50).The control group was given glucosamine sulfate and sodium hyaluronate joint cavity filling,the observation group was given leg press with visual feedback,they were treated 4 weeks.Assessing the pain degree through visual analog scale(VAS),hospital for special surgery knee score(HSS)as the indicator of motor function,inflammatory factor(TNF-α,IL-6,and IL-8)in the joint fluid.Results The score of VAS were lower than pretherapy(P<0.05),the degree of VAS of observation group were lower than control group(P<0.05).The score of HSS were higher than pretherapy(P<0.05),the degree of VAS of observation group were higher than control group(P<0.05).The inflammatory factor(TNF-α,IL-6,and CRP)in the joint fluid were lower than pretherapy(P<0.05),and the observation group were lower than control group(P<0.05).Conclusions Giving sodium hyaluronate joint cavity filling combined with exercise therapy can improve the function of joint.

Analysis of the relative factors affecting the functional restoration of knee joint after the fracture of patella

Objective To explore the relative factors affecting the functional restoration of knee joint after the fracture of patella, and to anticipate the effect of middle-term and short-time rehabilitation therapy. Method 23 patients with limited flexion function of knee joint after the fracture of patella, accepted the routine rehabilitation treatment in out -patient service, and some of the patients adopted local heat therapy at the same time. The 13 factors have been selected for regression analysis step by step under the help of SPSS statistical software. Result The flexible degree of the knee joint before rehabilitation (X1), the non-smooth posterior edge of patella (X2), and the immobilization time of the joint (X3) are relative factors for the flexible degree of knee joint 1 month after rehabilitation (Y1) and the flexible degree of knee joint 3 months after rehabilitation (Y2), and Y1 can also be affected by whether surgery therapy or not (X4), (partial regression coefficient P< 0.05). The differences between theoretical mean and practical mean of Y1 and Y2 are 5.6% and 4.2% respectively in the 23 cases. Conclusion The flexible degree of the knee joint before rehabilitation, whether the posterior edge of patella is smooth or not, and the immobilization time of the joint are relative factors affecting the middle-term and short-term flexible function of knee joint after the fracture of patella, and short-term restoration can also be affected by whether surgery therapy or not. The effects of middle-term and short-term rehabilitation can be predicted by regression equation primarily.