Operative Versus Nonoperative Management of Pediatric Proximal Humerus Fractures:A Meta-Analysis and Systematic Review

Background@#Proximal humerus fractures account for 2% of all pediatric fractures. A nonoperative approach is the treatment of choice for most of these fractures; however, debates continue regarding the treatment of displaced fractures, especially in adolescents. In this study, we aimed to examine demographic data and treatment strategies for proximal humerus fractures in the pediatric population by conducting a meta-analysis. Additionally, we investigated the preferred surgical technique for operative treatment. @*Methods@#A systematic online search of databases, including Embase, Medline, PubMed, and Cochrane Library, was conducted to identify studies that matched our search criteria. Data collection was completed on May 1, 2022. Age, sex, degree of angulation, Neer-Horwitz classification, Salter-Harris classification, treatment method (operative vs. nonoperative), and instrument used for internal fixation were classified and documented. Effect size analysis was performed using odds ratios (ORs) or weighted mean differences (WMDs) with 95% confidence intervals (CIs), based on data types. @*Results@#Eight studies met our inclusion criteria. Overall, 33% of the patients (n = 195) underwent operative treatment, whereas 67% of them (n = 392) received nonoperative treatment. Among the demographic risk factors, severely displaced fracture type (OR, 10.00; 95% CI, 1.56−64.22; p = 0.020) and older age (WMD, 3.26; 95% CI, 2.29−4.23; p < 0.001) were significantly associated with operative treatment. There was no significant difference in the preference for percutaneous pinning or intramedullary nailing, the most frequently employed surgical techniques (OR, 5.09; 95% CI, 0.65−39.58; p = 0.120). @*Conclusions@#The operative treatment rate in pediatric proximal humerus fractures was 33%, which increased to 60% in severely displaced fractures (Neer-Horwitz grade III/IV). Severely displaced fractures and older age significantly contributed to the establishment of a treatment strategy for operative treatment. The choice of surgical technique may seem to be based on the anatomical location of the fracture rather than the surgeon’s preference.

In Vitro Anti-Inflammation and Chondrogenic Differentiation Effects of Inclusion Nanocomplexes of Hyaluronic Acid-Beta Cyclodextrin and Simvastatin

The aim of this study was to prepare inclusion nanocomplexes of hyaluronic acid-β-cyclodextrin and simvastatin (HA-β-CD/SIM) and evaluate in vitro anti-inflammation effects on lipopolysaccharide (LPS)-activated synoviocytes and chondrogenic differentiation effects on rat adipose-derived stem cells (rADSCs). The β-CD moieties in HA-β-CD could incorporate SIM to form HA-β-CD/SIM nanocomplexes with diameters of 297–350 nm. HA-β-CD/SIM resulted in long-term release of SIM from the nanocomplexes for up to 63 days in a sustained manner. In vitro studies revealed that HA-β-CD/SIM nanocomplexes were able to effectively and dose-dependently suppress the mRNA expression levels of proinflammatory markers such as matrix metallopeptidase-3 (MMP-3), MMP-13, cyclooxygenase-2 (COX-2), a disintegrin and metalloproteinase with thrombospondin motifs-5 (ADAMTS-5), interleukin-6 (IL-6), and tumor necrosis factor (TNF-α) in LPS-stimulated synoviocytes. HA-β-CD/SIM-treated rADSCs significantly and dose-dependently enhanced mRNA expressions of aggrecan, collagen type II (COL2A1), and collagen type X (COL10A1), implying that HA-β-CD/SIM greatly induced the chondrogenic differentiation of rADSCs. Conclusively, HA-β-CD/SIM nanocomplexes will be a promising therapeutic material to alleviate inflammation as well as promote chondrogenesis.

Limb Lengthening in Patients with Achondroplasia

PURPOSE: Although bilateral lower-limb lengthening has been performed on patients with achondroplasia, the outcomes for the tibia and femur in terms of radiographic parameters, clinical results, and complications have not been compared with each other. We proposed 1) to compare the radiological outcomes of femoral and tibial lengthening and 2) to investigate the differences of complications related to lengthening. MATERIALS AND METHODS: We retrospectively reviewed 28 patients (average age, 14 years 4 months) with achondroplasia who underwent bilateral limb lengthening between 2004 and 2012. All patients first underwent bilateral tibial lengthening, and at 9-48 months (average, 17.8 months) after this procedure, bilateral femoral lengthening was performed. We analyzed the pixel value ratio (PVR) and characteristics of the callus of the lengthened area on serial radiographs. The external fixation index (EFI) and healing index (HI) were computed to compare tibial and femoral lengthening. The complications related to lengthening were assessed. RESULTS: The average gain in length was 8.4 cm for the femur and 9.8 cm for the tibia. The PVR, EFI, and HI of the tibia were significantly better than those of the femur. Fewer complications were found during the lengthening of the tibia than during the lengthening of the femur. CONCLUSION: Tibial lengthening had a significantly lower complication rate and a higher callus formation rate than femoral lengthening. Our findings suggest that bilateral limb lengthening (tibia, followed by femur) remains a reasonable option; however, we should be more cautious when performing femoral lengthening in selected patients.

case of metatropic dysplasia: operative treatment of severe kyphoscoliosis and limb deformities

Metatropic dysplasia is a rare but severe spondyloepimetaphyseal dysplasia characterized by long trunk and short extremities. The exact incidence is not known; however, 81 cases have been reported in the literature till now. Due to progressive kyphoscoliosis, there is a reversal of proportions in childhood [shortening of trunk with relative long extremities]. The diagnostic radiographic findings include marked platyspondyly [wafer-thin vertebral bodies], widened metaphyses [dumbbell-shaped tubular bones] and small epiphysis and a specific pelvic shape. The severe kyphoscoliosis is relentless and resistant to conservative treatment with bracing. Operative treatment is controversial due to the recurrence of deformity despite aggressive correction. We, here in report a case of this rare dysplasia and its follow-up after corrective surgery for spine and limb deformity. The excellent correction and good functional pulmonary status at 6-year follow-up has never been previously reported.

Fibrocartilaginous Intramedullary Bone Forming Tumor of the Distal Femur Mimicking Osteosarcoma

Fibrocartilaginous dysplasia (FCD) has occasionally led to a misdiagnosis and wrong decision which can significantly alter the outcome of the patients. A 9-yr-old boy presented with pain on his left distal thigh for 6 months without any trauma history. Initial radiographs showed moth eaten both osteolytic and osteosclerotic lesions and biopsy findings showed that the lesion revealed many irregular shaped and sclerotic mature and immature bony trabeculae. Initial diagnostic suggestions were varied from the conventional osteosarcoma to low grade central osteosarcoma or benign intramedullary bone forming lesion, but close observation was done. This study demonstrated a case of unusual fibrocartilaginous intramedullary bone forming tumor mimicking osteosarcoma, so that possible misdiagnosis might be made and unnecessary extensive surgical treatment could be performed. In conclusion, the role of orthopaedic oncologist as a decision maker is very important when the diagnosis is uncertain.

The Effect of Medial Arch Support for Flexible Flat Foot of Children / 대한족부족관절학회지

PURPOSE: The author evaluated the clinical and radiological results after wearing the medial arch supports in children. MATERIALS AND METHODS: 103 patients who had symptomatic flat feet were evaluated from march, 2002 to may 2009. All patients wore the medial arch supports according to the symptoms. We measured parameters at weight-bearing radiographs before and after medial arch support were worn. We also evaluated the clinical scores using the AOFAS score. RESULTS: Mean age of patients was 97 months (11-204 months), all foot of patients involved bilaterally. Mean talo-first metatarsal angle of right foot was 17.7+/-9.4 and left foot was 19.96+/-9.5 degrees at AP radiograph in pre-wearing state. Mean calcaneal pitch angle of right foot was 12.0+/-5.3 and left foot was 11.9+/-5.8 degrees at lateral radiograph in pre-wearing state. Mean talo-first metatarsal angle of right foot was 14.4+/-8.05 and left foot was 13.1+/-8.77 degrees at AP radiograph in post-wearing state. Mean calcaneal pitch angle of right foot was 16.4+/-5.75 left foot was 16.5+/-5.6 degrees at lateral radiograph in post-wearing state. The radiographic angles between pre-wearing and post-wearing state were statistically significant (p<0.05). Mean pre-wearing AOFAS hindfoot score was 66.7+/-9.25, midfoot score was 60.0+/-9.34 forefoot score was 57.1+/-11.8. Mean post-wearing AOFAS hindfoot score was 73.2+/-9.73, midfoot score was 68.1+/-10.1, forefoot score was 67.2+/-11.4. The forefoot score was highest improving scores among the AOFAS scores. CONCLUSION: From our study, we concluded that medial arch support was effective for symptomatic flat feet of children in radiological and clinical results from our study.

Comparison of Cytokine Expression in Mesenchymal Stem Cells from Human Placenta, Cord Blood, and Bone Marrow

Mesenchymal stem cells (MSCs) are capable of self-renewal and differentiation into lineages of mesenchymal tissues that are currently under investigation for a variety of therapeutic applications. The purpose of this study was to compare cytokine gene expression in MSCs from human placenta, cord blood (CB) and bone marrow (BM). The cytokine expression profiles of MSCs from BM, CB and placenta (amnion, decidua) were compared by proteome profiler array analysis. The cytokines that were expressed differently, in each type of MSC, were analyzed by real-time PCR. We evaluated 36 cytokines. Most types of MSCs had a common expression pattern including MIF (GIF, DER6), IL-8 (CXCL8), Serpin E1 (PAI-1), GROalpha(CXCL1), and IL-6. MCP-1, however, was expressed in both the MSCs from the BM and the amnion. sICAM-1 was expressed in both the amnion and decidua MSCs. SDF-1 was expressed only in the BM MSCs. Real-time PCR demonstrated the expression of the cytokines in each of the MSCs. The MSCs from bone marrow, placenta (amnion and decidua) and cord blood expressed the cytokines differently. These results suggest that cytokine induction and signal transduction are different in MSCs from different tissues.

Muscle Imbalance in Volleyball Players Initiates Scoliosis in Immature Spines: A Screening Analysis

STUDY DESIGN: Retrospective comparative study using radiographs and clinical findings. PURPOSE: To test the hypothesis that asymmetric loading of immature spines in young athletes initiates scoliosis. OVERVIEW OF LITERATURE: Scoliosis in athletes has been reported in the literature, but its causative factors have not been investigated. METHODS: We compared the incidence, type and magnitude of scoliotic curves in volleyball players with those in the non-player population. One hundred sixteen adolescent volleyball players were grouped for selective screening. Data regarding their playing duration, handedness, age, height, and menarchal status (in girls) were recorded, along with clinical examination and radiological investigation when necessary. We analyzed data from 46,428 non-player school children, and their data were compared to athletes to determine differences. RESULTS: Volleyball players had a statistically significant increase in the incidence of scoliotic spinal curves. Playing hand dominance was related to the curve direction. Cobb angle had no significant correlation with the duration of playing. CONCLUSIONS: There is a five-fold increase in the incidence of mild scoliosis in volleyball players. A high percentage (41%) of asymmetry was present on the Adams forward bending test, as compared to controls. The curves were either thoracic or thoracolumbar.

Effect of Aging on the Pluripotential Capacity of Human Bone Marrow Derived Mesenchymal Stem Cells / 대한정형외과학회잡지

PURPOSE: The aim of study was to compare the differentiation capacity of mesenchymal stem cells (MSCs) obtained from human bone marrow (BM) according to the age of the donors. MATERIALS AND METHODS: MSCs were isolated from the BM of young (n=16, 12.5+/-5.8 years) and elder (n=4, 48.5+/-7.2 years) patients with the consent of them. We analyzed the cell morphology and the cell surface markers of the MSCs. In addition, we assessed the cell senescence with serial cultures from both age groups. Cell pluripotentiality was analyzed by osteogenic, chondrogenic, and adipogenic induction media. We performed RT-PCR, a measurement of expression of alkaline phosphatase, and staining with von Kossa, safranin O, and oil red O stain. RESULTS: All of the MSC samples tested, irrespective of the age of the donors, MSCs were all successfully isolated from twenty bone marrows. However, the number of cells of from the young donors was five times greater than that of the elderly donors. Senescence was observed over 10 passages in both age groups. The immunophenotypes of both age groups showed similar patterns. MSCs obtained from young and older donors showed the potential to differentiate into osteogenic, chondrogenic, and adipogenic lineages with no difference for both age groups. CONCLUSION: Our study supports that age does not influence the pluripotential capacity of human BM derived MSCs.

Study of Bone Quality and Growth Characteristics of Growth Plate following Limb Transplantation between Animals of Different Ages-results of an Experimental Study on Male Syngeneic Rats / 대한정형외과학회잡지

BACKGROUND: Osteoporosis of transplanted/grafted bone is well known in the immediate post bone transplantation/bone grafting period. In limb transplantation, the growth plates in the transplanted limbs retain their longitudinal growth properties. However, there is a paucity of reports on what happens to the bone and the growth potential of the growth plate when limb transplantation between a juvenile donor and an adult recipient is performed. MATERIALS AND METHODS: Ten juvenile to juvenile hind limb transplants and five juvenile to adult hind limb transplants were performed in male syngeneic Lewis rats. Osteoporosis in the isochronograft as well as the heterochronograft limbs was measured by 3D micro-CT. In addition, the increase in tibial length, after transplantation was measured and compared with the increase in the tibial length of the opposite non-operated limbs. RESULTS: The 3D CT parameters indicate a significantly inferior bone quality in the heterochronografts compared with the isochronografts. After transplantation, the increase in the tibial length of the isochronografts was similar the increase in length of the opposite juvenile non operated tibiae and the heterochronograft tibias. CONCLUSION: Age is a significant factor that affects the bone quality, resulting in post transplant osteoporosis in heterochronografts compared with isochronografts. However, the growth plate after transplantation remains unaffected by the difference in age and continues to grow at its own inherent rate in adult recipients as it does in the juvenile recipients.

PHEX Gene Mutations and Genotype-Phenotype Analysis of Korean Patients with Hypophosphatemic Rickets

X-linked hypophosphatemic rickets (XLH) results from mutations in the PHEX gene. Mutational analysis of the PHEX gene in 15 unrelated Korean patients with hypophosphatemic rickets revealed eight mutations, including five novel mutations, in nine patients: two nonsense mutations, two missense mutations, one insertion, and three splicing acceptor/donor site mutations. Of these, c.64G>T, c.1699C>T, c.466_467 insAC, c.1174-1G>A, and c.1768+5G>A were novel mutations. To analyze the correlation between genotype and phenotype, phenotypes were compared between groups with and without a mutation, in terms of mutation location, mutation type, and sex. Skeletal disease tended to be more severe in the group with a mutation in the C-terminal half of the PHEX gene, but no genotype-phenotype correlation was detected in other comparisons. Further extensive studies of the PHEX gene mutations and analyses of the genotype-phenotype relationships are required to understand PHEX function and the pathogenesis of XLH.

Fibular Hemimelia: A Case Report

Fibular hemimelia is the most common congenital absence or hypoplasia of long bone. In addition to fibular absence or hypoplasia, this entity also includes various combined abnormalities of the lower limbs. We present here three cases of fibular hemimelia who underwent diagnosis and treatment in our hospital. Wee especially focus on the imaging findings of the plain radiographs, and we compare them with the findings found at another presentation.

Clinical Outcomes of Distraction Osteogenesis in First Brachymetatarsia / 대한정형외과학회잡지

PURPOSE: To evaluate the clinical results of lengthening in first brachymetatarsia using a distraction osteogensis with an external fixator. MATERIALS AND METHODS: Fifteen cases in nine patients, who had received firstmetatarsal distraction osteogenesis from January 1996 to December 2002, were enrolled in this study. At the final follow-up, the application time of the external fixator was measured and the percentage of lengthening, healing index, complication rate, and the patients satisfaction was analyzed. The patients satisfaction was evaluated using the American Orthopedic Foot and Ankle Society (AOFAS) scores, which were scored according to the level of stiffness, pain, function, and alignment. RESULTS: The score according to the AOFAS-Hallux Metatarsophalangeal joint and Inter-Phalangeal joint scale was excellent in 13 patients and good in 2. All patients were satisfied with the procedure. The average percentage of lengthening was 48.7%. The average healing index was 72.8 days/cm. The major complication was a cavus foot, which was noticed in four feet. All the first toes showed some decrease in motion at the metatarsophalangeal joint. The other complications were hallux valgus, angulation of the metatarsals, and a pin tract infection each in two feet. CONCLUSION: Distraction osteogenesis is an effective method for first brachymetatarsia. However, excessive lengthening can cause potential complications.

A Biomechanical Advantage of the Lengthening with an External Fixator Over an Intramedullary Nail: An Experimental Study in Saw Bones and Cadeveric Bones

PURPOSE: To know biomechanical differences in methods of limb lengthening between using monolateral external fixator and using external fixator over an intramedullary nail. MATERIALS AND METHODS: In acryl rods, saw-bone, and cadeveric bone, we created two lengthening models of using monolateral external fixator and using external fixator over an intramedullary nail. The axial compression test was done on the site of osteotomy for lengthening. To fix the models, half pins of 5 mm in diameter and nails of 9 mm in diameter were used. Using MTS (Material Test System) machine, we evaluated the differences of axial stiffness according to the presence of an intramedullary nail or the numbers of half-pins which were fixed at each side of osteotomy. RESULTS: Lengthening over an intramedullary nail, comparing to monolateral external fixator only, increased the axial stiffness by 1.1~1.2 times in acryl rods, 1.2~1.6 times in saw bones, and 15.6~15.9 times in cadeveric bones when the same numbers of half-pins were used. In saw bone and cadaveric bone, the group of two half pins in lengthening over an intramedullary nail was stiffer than the group of three pins in lengthening with monolateral external fixator. CONCLUSION: In the distraction of the limb, the addition of an intramedullary nail may increase the axial stiffness of the frame of monolateral external fixator. In lengthening over an intramedullary nail, it is enough to distract the bone with fixing two half pins at each sides of osteotomy.

Femoral Lengthening with External Fixator over the Intramedullary Nail / 대한정형외과학회잡지

PURPOSE: The results and complications of femoral lengthening over an intramedullary nail with a external fixator in patients with limb length discrepancy were retrospectively reviewed. MATERIALS AND METHODS: After lengthening 22 femoral segments, all patients were followed-up for a mean of 3.2 years (range, 2 to 5.2 years). They ranged in age from 13 to 35 years (average age, 22.2 years) at the time of the index procedure. The mean lengthening was 5 cm (2.7 to 8.1 cm), and the external fixator was removed after a median 135.9 days (range, 59 to 210 days). The mean external fixation index was 23.8 days/cm of lengthening (range, 11.1 to 34.7 days/cm of lengthening). RESULTS: Nineteen patients achieved the length of their pre-operative goal. However, there were 3 failures with osteomyelitis and the removal of the nail, which had a past history of infection or open trauma. There were 4 knee joint complications when the lengthening was over 20%. These included three cases of a patella subluxation and one case of a posterior knee subluxation. In the other complications, there was one case of a collapse in the lengthened segment with a breakage of the locking screws. CONCLUSION: Although lengthening over a nail can reduce the duration of external fixation, caution is needed in order to prevent complications.

High Flex Knee Arthroplasty and Range of Motion / 대한정형외과학회잡지

PURPOSE: The aim of this prospective study was to determine which factors are predictive of the post operative range of motion and to evaluate the short-term clinical results after total knee arthroplasty using The Nexgen Legacy Knee LPS-Flex fixed bearing knee system replacement. MATERIALS AND METHODS: A total of 67 patients (101 knees) were enrolled in this study. 101 knees were operated on using the LPS-Flex fixed bearing knee system replacement. The same surgeon performed the surgery between December 2001 and March 2002. The patients' ages ranged from 52 to 77 years, with an average of 68.4 years. Preoperatively the factors considered were the age of the patient, gender, the body mass index, the flexion contracture and further flexion possible. The factors considered postoperatively were patellar tilting and displacement, the postoperative knee and functional score, and a varus deformity. The patients were followed up once every 3 month for up to 2 years. RESULTS: At the latest follow-up, the average flexion in this series was 130.8degrees (range, 90degrees-150degrees). Thirty knees could attain more than 140degrees flexion. Twenty patients could comfortably kneel down. The 53 patients could sit cross-legged. The eleven knees could attain less than 120degrees of flexion at the final follow-up. There was a significant improvement in flexion at each successive review 12 months after surgery. The most important factor that influenced the range of motion after an arthroplasty was the preoperative range of flexion. The average Knee Society knee score was 90 points (range, 80-100), and the function score was 91 points (range, 45-100). CONCLUSION: A total knee arthroplasty with LPS-flex showed an excellent range of motion and satisfactory early clinical results. The most important factor that influences the range of motion after an arthroplasty is the preoperative range of flexion.

Posterior Cruciate Ligament Reconstruction with combined graft of Artificial Ligament and Bone - Patellar Tendon - Bone Autograft

No Abstract Available.

Spontaneous Bone Regeneration in Surgically Induced Bone Defects in Young Rabbits / 대한정형외과학회잡지

PURPOSE: To evaluate and compare the spontaneous regeneration repair process in femoral bone defects in 6-week-old rabbits and to compare the healing time periods between different rabbit groups. MATERIALS AND METHODS: Bone defects were created at the femur mid-shaft and an external fixator was applied in 50 rabbits. The periosteum was resected in 10 rabbits (defect size: 15%, 25%) and left untouched in the remaining rabbits. Forty rabbits were divided into four groups according to the percentage of bone defects (15%, 20%, 25%, 30%). Radiographs were taken weekly to evaluate the bone regeneration and union. The bone union time was measured between the osteotomy and the cortico-medullary differentiation by examining radiographs. The healing index was defined as the union time (week) per amount (cm) of bone defect. Eight rabbits, 2 from each groups with the bone defects, were investigated by histopathologic examination. RESULTS: The mean union time was approximately 7.0 to 7.3 weeks. The healing index in groups that had a large percentage of bone defects was less than in groups that had a small percentage of bone defects. The periosteum-resected group did not show bone regeneration. Histopathologic examinations showed intramembranous and atypical endochondral ossifications along the periosteum and typical endochondral ossification at the center of the bone defects. CONCLUSION: Spontaneous bone regeneration may be used in children to fill the bone defect instead of performing an internal bone transport. Spontaneous bone regeneration is useful in cases of mid-shaft bone defects or when the remaining bone fragments are large enough for an external fixation application.

The Change of Mechanical Angle after High Tibial Osteotomy using Blade Plate / 대한정형외과학회잡지

PURPOSE: To search cause of recurrence of varus deformity and to correlate the mechanical angle of the knee joint at the third postoperative month following high tibial osteotomy to the final mechanical angle and to the clinical results. MATERIALS AND METHODS: Study of thirty knee joints with lateral closed wedge osteotomy and fixation with 90-degree angle blade plate. Plateau-Blade angle was measured to evaluate the loss of correction at the osteotomy site. At the third postoperative month, the knees were divided into two groups according to the mechanical angle. Group I included the patients with valgus angle (16 knees) and group II included the patients with varus angle (14 knees) . The final mechanical angle was measured and the clinical results were evaluated with the knee score and the function score of Knee Society. RESULTS: Plateau-Blade angle decreased 2.5 in group I and 4.8 in group II at postoperative three month. At the final follow-up, the loss of correction angle was 0.8 in group I and 2.3 in Group II (p>0.05) . The final knee score was 86 in group I and 80 in group II (p>0.05) . The final function score was 90 in Group I and 80 in Group II. CONCLUSIONS: Because the final function score of valgus angle group is superior to that of varus angle group and recurrence of varus was mainly occur within postoperative three months, meticulous postoperative management needed to maintain valgus mechanical angle.

Classification of Transient Synovitis with Magnetic Resonance Imaging / 대한정형외과학회잡지

PURPOSE: To classify the type of transient synovitis and determine a treatment plan using MRI. MATERIALS AND METHODS: From March 1985 to October 1998, 37 hips in 33 children with clinical symptoms of transient synovitis were evaluated with MRI. The average age of the patients was 7.5 years (range, 3.5-15 years) . The mean follow-up period was 18 months (range, 12-36 months) . The 37 hips were classified as grade l, ll, lll, or lV according to the amount of accumulated joint fluid on MRI. RESULTS: Of 37 hips with transient synovitis, 36 hips had no involvement of epiphysis and metaphysis and one hip had a cyst and bone marrow edema in the metaphysis on MRI scans. The amount of joint fluid was classified as seen on MRI scans: grade 1 in 2 hips, grade 2 in 14 hips, grade 3 in 5 hips, and grade 4 in 16 hips. CONCLUSION: MRI is a very useful diagnostic tool to classify and determine the treatment plan for transient synovitis. In patients with grade 3 and 4 joint fluid, the risk of vascular compromise of the femoral epiphysis could be higher. These patients should be hospitalized and immobilized in flexed position of the hip. Patients with grade 1 and 2 joint fluid can be treated at home with immobilization.