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Average 4.3 of 53 Ratings
Technique guide are not considered high yield topics for orthopaedic standardized exams including the ABOS, EBOT and RC.
Which of the following is true regarding matrix metaloproteinases (MMPs)?
They are activated by chelating agents
They mediate the destruction of cartilage in septic arthritis
Toll-like receptors inhibit the formation of MMPs
They have a anabolic effect on cartilage
Stromelysin is an indirect antagonist of many MMPs
Select Answer to see Preferred Response
Matrix metalloproteinases have been associated with the destruction of cartilage in septic arthritis.
Matrix metalloproteinases and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs), are crucial to extracellular matrix remodeling in normal tissue development and maintenance. Additionally, their over-expression has been associated with cartilage degradation in diseases such as rheumatoid arthritis, osteoarthritis, and septic arthritis. In septic arthritis, toll-like receptors activate the NF-kB pathway which leads to the production of MMPs and resulting cartilage destruction.
Papathanasiou et al. investigate the role of toll-like receptors in septic arthritic chondrocytes. They demonstrated that TRL-1, 2, and 6 were up-regulated in septic chondrocytes and that TRL-2 directly affects the NF-kB pathway that leads to the production of MMPs.
Illustration A shows the pathway through which MMPs work to destroy cartilage.
Answer 1: Chelating agents bind to metals that serve to activate MMPs, thus inactivating them.
Answer 3: Toll-like receptors have been linked to the NK-kB pathway, which activates the formation of MMPs.
Answer 4: MMPs have a catabolic effect on cartilage.
Answer 5: Stromelysins are a subgroup of matrix metalloproteinases.
Papathanasiou I, Malizos KN, Poultsides L, Karachalios T, Oikonomou P, Tsezou A.
J Orthop Res. 2011 Feb;29(2):247-51. Epub 2010 Aug 25. PMID: 20740673 (Link to Abstract)
Papathanasiou, JORE 2011
Please rate question.
Average 3.0 of 17 Ratings
A 3-year-old presents with a 24-hour history of limping and progressive inability to bear weight. The parents recount no history of trauma, but note that he recently had an upper respiratory infection. A clinical photo is shown in Figure A. The patient’s vital signs are stable. Physical exam is limited because of pain. A hip ultrasound is shown in Figure B. Laboratory values are as follows: WBC-15.0 (97% PMN), ESR-120, CRP-5.0. What is the next best step for this patient?
Admit for observation
Repeat hip ultrasound
Obtain an MRI
Start the patient on IV antibiotics
Emergent hip arthrotomy with irrigation and debridement
Based on the clinical findings and figures shown, the patient has developed a septic arthritis of the left hip. As the patient has 3 out of the 4 Kocher criteria, he has a 93% chance of having a septic hip. The next best step in management would be to take the patient to the operating room for an emergent irrigation and debridement of the affected hip.
Septic arthritis in the pediatric population often occurs in the first few years of life, with 50% of cases occurring in those less than 2 years of age. Patients may present with a toxic appearance. The likelihood of a patient having a septic hip can be ascertained with use of the Kocher criteria (WBC > 12, ESR > 40, T > 38.5 and an inability to bear weight on the affected hip). Patients meeting all four criteria have a 99% chance of having a septic hip, whereas those meeting just one of the criteria have a 3% chance of having a septic hip. Rapid breakdown of the hyaline articular cartilage occurs via enzymes (matrix metalloproteinases & hyaluronidase) produced by the bacteria. This may be mitigated with an emergent surgical irrigation and debridement.
Rutz et al. review septic arthritis of the pediatric hip. Diagnosis in infants may be difficult because this subset of patient do not always develop fevers. They recommend arthroscopic irrigation and debridement for those patients with an acute presentation and no evidence of osseous complications on radiographs. For those with a subacute presentation or radiographically visible complications of the femoral head, an open arthrotomy should be completed.
Pillai et al. studied the appearance of the pediatric acetabulum on ultrasound in comparison with plain radiographs. They suggest that a static ultrasound evaluation can be an effective method of screening for developmental hip dysplasia.
Figure A shows a patient with a hip effusion, holding the extremity in an flexed, abducted and externally rotated position. Figure B shows an ultrasound demonstrative of a joint effusion. The region of capsular distention can be seen anterior to the femoral neck.
Answer 1: Observation is not indicated in this clinical scenario.
Answer 2: The hip ultrasound shown demonstrates an effusion; repeating the ultrasound will not change management.
Answer 3: Obtaining an MRI may be useful if the ultrasound were negative. It would help evaluate the extremity for evidence of osteomyelitis
Answer 4: As the patient is not septic, intraoperative cultures should be obtained prior to the administration of antibiotics.
Rutz E, Brunner R.
Hip Int. 2009 Jan-Mar;19 Suppl 6:S9-12. PMID: 19306242 (Link to Abstract)
Rutz, HIPIN 2009
Pillai A, Joseph J, McAuley A, Bramley D.
Arch Orthop Trauma Surg. 2011 Jan;131(1):53-8. Epub 2010 Apr 9. PMID: 20379825 (Link to Abstract)
Pillai, AOTS 2011
Average 4.0 of 18 Ratings
A 2-year-old child is diagnosed with a septic hip. Initially, no organisms grew on the standard blood agar plate. However, after 1 week, the offending organism was recovered in an aerobic blood culture medium. Which of the following organisms was the most likely cause?
Kingella kingae is a fastidious organism which is recovered on blood culture medium, recently with the addition of the BACTEC blood culture system (Illustration A). Mycobacterium tuberculosis is grown on Lowenstein Jensen (LJ) medium, while Mycobacterium avium can be grown on the LJ or Middlebrook medium. Neisseria is typically grown on the Thayer-Martin medium. E-coli is grown on the Luria Bertani medium.
Petti et al studied the use of standard and extended blood culture incubation for Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella (HACEK) bacteria. Although all are fastidious organisms, they determined that standard incubation time on a blood culture medium is sufficient to recover HACEK bacteria.
Yugupsky et al investigated the recovery of Kingella kinage in solid media and the BACTEC automated blood culture system. The BACTEC system is shown in Illustration A. They concluded that the BACTEC blood culture system enhances the recovery of the bacteria in joint fluid over solid mediums. They concluded that Kingella kingae is a more common cause of pediatric septic arthritis than previously reported.
Yagupsky P, Dagan R, Howard CW, Einhorn M, Kassis I, Simu A.
J Clin Microbiol. 1992 May;30(5):1278-81. PMID: 1583131 (Link to Abstract)
Petti CA, Bhally HS, Weinstein MP, Joho K, Wakefield T, Reller LB, Carroll KC.
J Clin Microbiol. 2006 Jan;44(1):257-9. PMID: 16390985 (Link to Abstract)
Average 2.0 of 69 Ratings
A 2-year-old boy is seen for evaluation of a limp. His history is significant for a left knee infection treated with IV antibiotics as a neonate and a family history of cancer. Laboratory testing demonstrates a normal ESR and CRP. The remainder of his workup is negative. An AP pelvis is seen in Figure A. What was the most likely etiology of his condition?
Untreated neonatal hip infection
Slipped capital femoral epiphysis
The clinical scenario and images are consistent with a neglected pediatric septic hip. The AP pelvis in Figure A shows an absent left femoral head due to an untreated infection. Failure to diagnose an infected adjacent joint can lead to joint destruction and physeal damage with resultant deformity. Surgical options for hip deformity following a neglected infection include trochanteric osteotomy, proximal femoral varus osteotomy, and a modified Albee arthroplasy.
McCarthy at al reviewed the pediatric musculoskeletal infection principles and treatments in their Instructional Course Lecture. Prevention, prompt and accurate diagnosis, and timely intervention are needed to prevent late sequelae such as limb-length inequalities and angular deformities. Proper diagnosis includes evaluating adjacent joints of neonatal infections.
Peters et al reviewed the results of septic arthritis and physeal damage on overall growth. Growth plate arrest in the distal femur, proximal femur and proximal humerus accounted for angular deformities in neonates with prior joint infections. They recommended continued long-term growth monitoring of infected patients until age 9.
McCarthy JJ, Dormans JP, Kozin SH, Pizzutillo PD.
Instr Course Lect. 2005;54:515-28. PMID: 15948476 (Link to Abstract)
McCarthy, JBJS 2005
Peters W, Irving J, Letts M.
J Pediatr Orthop. 1992 Nov-Dec;12(6):806-10. PMID: 1452755 (Link to Abstract)
Peters, JPO 1992
Average 3.0 of 16 Ratings
An 8-day-old infant is admitted to the hospital for septic arthritis of the hip. Which of the following will most likely be the causative organism by culture?
Group B Streptococcus
Group B Streptococcus is the most common causative organism of neonatal septic arthritis. It should be noted in the subgroup of neonates who acquire nosocomial septic arthritis, Staph Aureus is more common than Group B Strep. These infections often arise from invasive procedures such as central lines and indwelling catheters. Children in the first 2 years of life have the highest frequency of septic arthritis. In children 3 months of age to 2 years, H. Influenzae was traditionally the most common organism, but its prevalence has fallen significantly since the introduction of H. Flu vaccinations. In children over 2 years of age, Staph Aureus is the most common causative organism.
In an Instructional Course Lecture, McCarthy et al summarize the pathogenesis, evaluation, treatment, and prognosis of musculoskeletal infections in children. They emphasize long-term follow up as a musculoskeletal infection in a growing child may have further impact as the child ages.
Dan et al reviews a case series of pediatric septic hips to correlate the most common bacterial isolates in young infants.
Rev Infect Dis. 1984 Mar-Apr;6(2):147-55. PMID: 6374832 (Link to Abstract)
A 7-year-old boy developed a limp with right leg pain five days ago, and today has trouble bearing weight. On exam, he is lethargic and has chills. His temperature is 38.4 degrees centigrade. He points to his right inguinal region as the source of the discomfort. He winces with compression of his pelvis. Lab studies reveal a white blood cell count of 11,400/ul, CRP of 0.9 mg/dL (normal < 1.0 mg/dL), and erythrocyte sedimentation rate of 55 mm/h. A pelvis radiograph is shown in Figure A. Ultrasound guided aspiration of the right hip joint yields 9,000 leukocytes per mL. What is the most appropriate next step in management?
Further imaging of the pelvis
Open drainage and irrigation of the right hip joint
Repeat aspiration of the hip joint
Percutaneous screw fixation of the proximal femoral physis
Nonsteroidal antiinflamatory medications and observation
This patient has clinical signs of infection with symptoms localized to the pelvis. The differential diagnosis of an infectious presentation with NWB in a child should include: discitis, sacroilitis, transient synovitis, septic hip, osteomyelitis, and Iliopsoas abscess. Further imaging is required to confirm the diagnosis. The radiographs are not consistent with a slipped capital femoral epiphysis.
An appropriate workup has been completed for septic arthritis, which is a surgical emergency and prompts drainage and debridement of the hip joint. The Kocher criteria for septic arthritis include fever>38.5 degrees centigrade, inability to bear weight, ESR>40 mm/h, and WBC count>12,000/ul. In this case, 2/4 of the criteria are positive (inability to bear weight & ESR>40mm/h), which indicates approximately a 40% likelihood of septic arthritis. Synovial fluid analysis is used to either confirm or reject the hypothesis of suspected septic arthritis; an aspiration of < 50,000 leukocytes per mL virtually rules out sepsis of the joint.
The paper by Beaupre et al discusses that iliac osteomyelitis is a rare cause of pediatric hip pain, and it can usually be effectively treated with antibiotics alone. Repeat aspiration of the joint is indicated if there is suspicion of a poorly done procedure, but it was image guided in this case. It is notable that a joint infection secondary to osteomyelitis is possible in the pediatric hip as result of the synovial reflections facilitating bacterial migration from the metaphysis to joint space. The synovial fluid analysis is critical in identifying presence or absence of joint infection.
Beaupré A, Carroll N.
J Bone Joint Surg Am. 1979 Oct;61(7):1087-92. PMID: 489653 (Link to Abstract)
Beaupré, JBJS 1979
Average 1.0 of 118 Ratings
An 18 month-old child has been brought to the emergency room by his mother. He had the sudden onset of hip pain 3 days ago and now won't put weight on the affected limb. The child is febrile and an ultrasound (longitudinal view of the proximal femur) shown in Figure A shows the unaffected hip on the left and affected hip on the right. The patient is taken to the operating room for hip aspiration which reveals 60,000 leukocytes with 95% polymorphonucleocytes. What is the most likely diagnosis?
Acute rheumatic fever
Juvenille rheumatoid arthritis (JRA)
This patient most likely has a septic hip based on clinical, radiographic, and laboratory data. Traumatic effusions have less than 5,000 leukocytes, toxic synovitis (5,000-15,000 leuckocytes with <25% PMNs), rheumatic fever (10,000-15,000 leukocytes with 50% PMNs), and JRA (15,000-80,000 leukocytes with 75% PMNs). Synovial fluid analysis for septic arthritis includes >50,000 leukocytes and >75% PMNs. The review article by Sucato et al notes that JRA can be present similarly to a septic joint with a hip effusion with high leukocyte count and >75% PMN's. However, they mention that JRA patients often have gradual onset of symptoms, less pain, usually continue weightbearing activities, and lack constitutional symptoms. Illustration A compares the sonographic findings in a normal hip compared to a hip with an effusion.
Sucato DJ, Schwend RM, Gillespie R.
J Am Acad Orthop Surg. 1997 Oct;5(5):249-260. PMID: 10795061 (Link to Abstract)
Sucato, JAAOS 1997
An 8-month old infant is brought by his parents to your office for fever and malaise. Your inspection of the patient is detailed in Image A. An oral temperature of greater than 38.5 has been found to be the best predictor of this child's condition. What is the second best predictor?
Elevated neutrophil count
Elevated rheumatoid factor
Presence of bacteria on CSF gram stain
The patient's clinical image reveals a flexed, abducted, and externally rotated left hip. This hip position maximizes intracapsular volume and indicates a left hip effusion as described in the review by Sucato.
Caird et al performed a Level 1 study that concluded that a temperature above 38.5 was the best predictor of septic arthritis followed in decreasing order by CRP, ESR, refusal to bear weight, and serum WBC count. An elevated rheumatoid factor can be seen in juvenile rheumatoid arthritis but fever is not part of the ACR (American College of Rheumatology) criteria. Presence of bacteria on CSF gram stain indicates a diagnosis of bacterial meningitis, which in isolation does not cause a flexed, abducted, and externally rotated hip. Illustration A shows the predicted probability of septic arthritis based on the number of factors present in the patient and compares Kocher's original 4 factors (ESR, WBC, fever, refusal to bear weight) and Caird's addition of CRP as a 5th factor.
Caird MS, Flynn JM, Leung YL, Millman JE, D'Italia JG, Dormans JP
J Bone Joint Surg Am. 2006 Jun;88(6):1251-7. PMID: 16757758 (Link to Abstract)
Caird, JBJS 2006
Average 3.0 of 31 Ratings
A 6-week old boy refused to move his left hip. The patient was delivered by C-section 4 weeks premature, but otherwise is healthy. He has been afebrile. Examination reveals some mild, diffuse swelling about the left proximal thigh. Passive motion of the hip elicits discomfort. An AP pelvis radiograph is shown in Figure A. What is the most appropriate next step in management?
This question is describing a scenario in which you must rule out a septic hip, and therefore the most appropriate next step in management is aspiration.
Prematurity and c-section are both risk factors for a septic hip in the new born.While there is no fever in this case, there is swelling, pain with passive motion, no active motion secondary to pain, and a radiograph which indicates an effusion in the hip as seen by lateral displacement of the left proximal femur. Suspicion for a septic hip should be high, and the next most appropriate step is a hip aspiration. If no fluid is obtained, arthrography should be performed to confirm intra-articular position of the needle. The aspirate should be sent for a stat CBC with diff, culture (aerobic, anaerobic and acid-fast bacilli +/- fungal), and gram stain. A WBC greater than 50,000/uL or a positive gram stain suggest septic arthritis and are an indication for surgical incision and drainage and initiation of IV antibiotics.
Kocher et al identified four independent multivariate clinical predictors of septic arthritis. These were fever, non-weight-bearing (not applicable in this case because the infant is not of ambulatory age), ESR greater than 40 ml/hr, and WBC greater than 12,000. The predicted probability of septic arthritis was 0.2% for 0 predictors, 3.0% for 1 predictor, 40.0% for 2 predictors, 93.1% for 3 predictors, and 99.6% for 4 predictors.
Answer 1: MRI may reveal an effusion or associated osteomyelitis abscess, but this is not appropriate because the additional hours spent obtaining an MRI could potentially lead to severe articular cartilage destruction (as an aside ultrasound would be a reasonable choice in some institutions when readily available since it is an easy, quick and noninvasive technique that can detect an effusion and guide aspiration of the hip if an effusion is present).
Answer 2: A CT scan would not be sensitive for an effusion or osteomyeletis, and therefore is not the most appropriate imaging modality.
Answer 3: Observation is not appropriate because septic arthritis of the hip constitutes a surgical emergency; the release of proteolytic enzymes by polymorphonuclear cells and bacteria in conjunction with increased intra-articular pressure can result in rapid irreversible hyaline cartilage degradation in as little as 6 hours in animal studies, with resultant joint destruction, deformity and lifelong arthritis & disability.
Answer 5: A Pavlick harness would be appropriate if there was any indication of hip dysplasia, including a positive Ortolani or Barlow sign, a Galeazzi sign or ultrasound evidence of hip dysplasia, none of which were described.
Kocher MS, Zurakowski D, Kasser JR
J Bone Joint Surg Am. 1999 Dec;81(12):1662-70. PMID: 10608376 (Link to Abstract)
Kocher, JBJS 1999
Average 2.0 of 57 Ratings
A 3-year-old boy presents with his caregiver with concerns regarding a long-standing gait disturbance. The birth history is unknown except for a prolonged ICU stay for sepsis. A pelvic radiograph is shown in Figure A. What is the most likely cause for this child's limp?
Developmental dysplasia of the hip
Residual effects of previous untreated septic hip arthritis
Acute femur fracture secondary to child abuse
This child is presenting with radiographic and clinical findings consistent with the sequelae of untreated septic hip arthritis. Specifically, the child is limping and there is complete destruction of the femoral head/neck in the pelvic radiograph. Furthermore, the radiograph is not consistent with any of the remaining choices.
Dobbs et al. review a case series of 5 patients with previous untreated septic arthritis, treated with proximal femoral osteotomy. The authors found all 5 patients had stable, painless, and functional hips.
Vitale and Skaggs review the diagnosis, treatment, and outcome of young patients (6 months to 4 years) with developmental dysplasia of the hip.
1) Slipped capital femoral epiphysis - radiographs would show the epiphysis displaced upon the femoral neck (Illustration A) and typically occurs in an older age group
2) Legg-Calve-Perthes disease - radiographs would show the epiphysis undergoing some stage of resorption or reossification (Illustration B)
3) Developmental dysplasia of the hip - radiographs would show the femoral head incompletely covered by a dysplastic acetabulum (Illustration C)
5) Femur fracture - radiographs would show a fracture (Illustration D)
Dobbs MB, Sheridan JJ, Gordon JE, Corley CL, Szymanski DA, Schoenecker PL
J Pediatr Orthop. 2003 Mar-Apr;23(2):162-8. PMID: 12604944 (Link to Abstract)
Dobbs, JPO 2003
Vitale MG, Skaggs DL
J Am Acad Orthop Surg. 9(6):401-11. PMID: 11730331 (Link to Abstract)
Vitale, JAAOS 2001
Average 3.0 of 23 Ratings
Which of the following Gram stain images most accurately represents the primary causative organism for pediatric osteomyelitis and septic arthritis?
Figure E shows gram positive cocci in clusters which is characteristic of Staphylococcus aureus, which causes >50% of septic arthritis cases and most cases of acute hematogenous osteomyelitis. Neonates with community-acquired septic arthritis are the only pediatric subgroup that have Group B strep as the most common causative organism.
Gram-positive bacterial cell walls are not permeable to an alcohol solvent and retains a purple dye. Gram-negative bacterial cell walls allow the dye complex to be extracted therefore appear colorless until they are counterstained with safranin and appear pink due to the counterstain.
The review article by McCarthy et al descibes the various causative organisms specific to each age in addition to S. aureus. Neonates have Group B streptococci, and gram-negative bacilli. Children less than 4 years have Streptococcus pneumoniae, Group A streptococcus, and Haemophilus influenza if not previously vaccinated. Children >4 years typically have S. aureus unless there are special circumstances (Shoe puncture=Pseudomonas, sickle cell disease= Salmonella).
Figure A shows gram negative cocci (N. gonorrhea), B shows gram positive rods (B. cereus), C shows gram negative rods (P. aeruginosa), D shows gram negative coccobacilli (B. fragilis).
Average 3.0 of 32 Ratings
In differentiating pediatric septic hip from transient synovitis, an elevated ESR (>40), history of fever, refusal to bear weight and what other finding has been identified as predictive of a septic hip?
Elevated absolute neutrophil count
Serum white blood cell count > 12,000 cells/cubic millimeter
Positive blood cultures
Pain with hip extension
Symptoms greater than 3 days
In the classic article by Kocher et al, the authors reviewed pediatric patients with septic arthritis and concluded that four independent multivariate clinical predictors were identified to differentiate between septic arthritis and transient synovitis: history of fever, non-weight-bearing, erythrocyte sedimentation rate of at least forty millimeters per hour, and serum white blood-cell count of more than 12,000 cells per cubic millimeter (12,000 cells/cubic millimeter). The predicted probability of septic arthritis was determined for all sixteen combinations of these four predictors and is summarized as less than 0.2 % for zero predictors, 3% for one predictor, 40% percent for two predictors, 93% for three predictors, and 99% for four predictors.
Caird et al performed a study that concluded that a temperature above 38.5 was the best predictor of septic arthritis followed in decreasing order by CRP>2 mg/dL, ESR, refusal to bear weight, and WBC count in the serum.
Illustration A is a table that compares Kocher's original 4 factors (ESR, WBC, fever, refusal to bear weight) and Caird's addition of CRP>2 mg/dL as a 5th factor.
A 10-month-old infant is brought to the emergency department for fevers, irritability, and avoidance of motion in the right leg. On physical exam, passive motion of the right hip elicits crying. An AP pelvis and an ultrasound of the right hip are shown in Figures A and B respectively. A hip aspiration yields 82,000 WBC with >80% PMNs. Which of the following is the strongest predictor of a poor prognosis?
CRP > 5mg/L
Delay in treatment >4 days
Age > 6 months
Absence of associated osteomyelitis
ESR > 40mm/hr
The clinical scenario is consistent with a pediatric septic hip. The AP pelvis in figure A shows soft-tissue swelling with mild subluxation of the right hip due to a septic effusion, and the ultrasound in figure B also shows a hip effusion. The hip aspiration is consistent with an infectious process. An aspirate with WBC >50,000 is highly suggestive of a septic hip. Jackson et al reviewed pediatric septic arthritis and describe four poor prognostic signs: age <6 months, joint effusion with underlying osteomyelitis, hip involvement, and delay in treatment >4 days. In a review of pediatric septic hips, Sucato et al state that hip aspiration is the most sensitive test and that I&D is required to prevent late sequlae.
Jackson MA, Nelson JD.
J Pediatr Orthop. 1982 Aug;2(3):313-23. PMID: 6752200 (Link to Abstract)
Jackson, JPO 1982
Average 4.0 of 22 Ratings
A member recently made a very astute comment questioning whether our introd...
HPI - History of swelling and discharging wound over the left gluteal region at the age of 2 months. Treated only with dressings. No surgical decompression done. Started walking with a painless limp at 1.5 years of age. Affected limb noted to be shorter.
How would you classify this lesion?
HPI - Patient had a sudden onset of pain in the right hip 14 days back.. she felt a clicking sensation while having her bath, no history of trauma... by the next day she developed an increase of pain and mild swelling of the hip and had developed fever and had pain in performing movements of the right hip.... usg report show hemarthrosis
Based on the clinical presentation and radiographs above, what is the most likely diagnosis?
HPI - Patient was treated in a private setup for septic hip 1 year back. He now presents with a painful hip and limp. He reports current intermittent fever.
What would be your next step in treatment, considering his ESR and CRP are still abnormal?
HPI - He had septic arthritis of hip joint in early childhood. Now infection has resolved.
Is there any procedure to reconstruct his hip joint
HPI - No H/O trauma, fall or fever.
How would you treat this injury?
HPI - 8 month old male presents with 4 day history of decreased movement of left hip, intermittent fever measured up to 101.5 F, and general fussiness.
How would you next proceed?
HPI - 12 yr old female c/o limping gait and mild to moderate pain in left hip.no fever or weight loss
What is the most likely diagnosis
HPI - no h/o fever, trauma, joint swelling
what is most likely diagnosis and treatment option