Missed slipped capital femoral epiphysis: illustrative cases and a review

A review of slipped capital femoral epiphysis

ABSTRACT

Hip pain in children is common, with causes ranging from the benign to destructive. This article reviews slipped capital femoral epiphysis (SCFE), one of the most common hip pathologies in preadolescents and adolescents, which often is missed or delayed in diagnosis because of its vague, atypical presentation.

Slipped Capital Femoral Epiphysis in an Adult with Panhypopituitarism: A Case Report

CASE

Our patient was a 31-year-old woman with previously undiagnosed panhypopituitarism who presented with bilateral slipped capital femoral epiphysis (SCFE). Together with endocrinology, her treatment plan involved medical management of her panhypopituitarism and surgical correction with femoral neck osteotomy. Hormone deficiencies were corrected 6 weeks after replacement therapy began, and the patient was cleared for surgery. By 5 months after osteotomy, examination revealed delayed union and prominent screws bilaterally. Hardware exchange and repeat internal fixation were then performed. At 8 weeks after revision, she presented with avascular necrosis, and the decision was made to proceed with total hip arthroplasty. A 5-year follow-up period was documented.

CONCLUSION

This case presented a rare look at SCFE in an adult patient with panhypopituitarism. Other systemic illnesses that can contribute to SCFE or other orthopaedic issues include, but are not limited to, multiple endocrine neoplasia syndromes, vitamin D deficiency, renal osteodystrophy, Kallmann syndrome, Klinefelter syndrome, and pathologies affecting the thyroid and pituitary gland.

Causes of Delayed Diagnosis of Slipped Capital Femoral Epiphysis: The Importance of the Frog Lateral Pelvis Projection

Delayed diagnosis and treatment is a universally reported problem that impairs the prognosis of slipped capital femoral epiphysis (SCFE). Quite frequently, a delayed diagnosis of SCFE is observed in spite of serial admissions and examinations of the limping adolescent. Why do health professionals globally fail to make a definitive diagnosis of SCFE during the first examination of the patient? A retrospective study of 36 adolescents treated for stable SCFE and two adolescents treated for unstable SCFE has been performed. In more than half of the delayed diagnosed stable slips (13/25, 52%), the diagnosis was set after serial examinations of the patient. Health professionals commonly order only the anteroposterior (AP) X-ray view of the pelvis when examining a non-traumatic limping adolescent. The frog lateral (FL) projection is usually spared in an attempt to limit the radiation exposure of the patient, especially in ambulating adolescents with mild symptoms. It is proposed that in the non-traumatic limping adolescent, the FL projection instead of the AP pelvis view should be requested by the health professional in order to timely diagnose a surgical emergency of the adolescent hip such as SCFE.

The Atypical Patient With Slipped Capital Femoral Epiphyses May Be at Increased Risk for a Missed Contralateral Slip

Slipped capital femoral epiphysis (SCFE) is a commonly encountered hip disorder. The goal of this study was to describe the incidence of missed contra-lateral SCFE as well as to identify risk factors. The authors hypothesized that contralateral slips are more often missed in patients with severe involvement of the treated side. After institutional review board approval was obtained, a retrospective chart review was performed of all pediatric patients who were treated for sequential and bilateral SCFE at a single institution during an 18-year period. Medical records were reviewed for demographic features and attending surgeon. Radiographs were reviewed for skeletal maturity, Klein's line, and severity of the treated slip. All radiographs were reviewed by 3 pediatric orthopedists. Contralateral SCFE was deemed present when consensus was achieved. Comparisons were made with Fisher's exact test, and P<.05 was considered significant. Of the records that were reviewed, 56 patients met the study criteria. Of these, 19 patients had bilateral involvement and 5 missed slips were identified (8.9%). The patients with missed disease tended to be younger (mean age, 10.8 vs 11.4 years), with a lower body mass index. Fellowship-trained pediatric surgeons were more likely to identify bilateral disease compared with orthopedists without pediatric training (P=.0065). A contralateral slip was more likely to be present in patients who had a positive finding for Klein's line (P<.0001). Severity of the treated slip did not increase the likelihood of missing a contralateral slip. Although Klein's line is a useful tool in the diagnosis of SCFE, a false-negative rate of 40% was observed. The authors recommend increased vigilance when an "atypical" patient with SCFE presents with unilateral disease. [Orthopedics. 2020;43(2):e114-e118.].

Bilateral Valgus Slipped Capital Femoral Epiphysis in an 11-year-old Girl

Valgus slipped capital femoral epiphysis (SCFE) is very infrequent, and it is characterized by a superolateral displacement of the epiphysis on the metaphysis. To date, less than 100 cases of valgus SCFE have been described in the literature. Bilaterality of valgus SCFE is extremely rare, and it presents management challenges to the treating orthopedic surgeons. Herein, we report the case of an 11-year-old Saudi Arabian girl presented to clinic with a one-year history of bilateral hip pain and limping. Past medical history was negative for endocrinopathies, hemoglobinopathies, bone disorders, trauma or radiation therapy to the pelvis. On physical examination, the patient looked tall and obese. On clinical examination, the patient showed a waddling gait and an external rotation on walking. A frog-leg lateral radiograph showed bilateral SCFE with a valgus deformity. The right and left femoral neck-shaft angles measured 154.3 and 148.2 degrees, respectively. Computed tomography (CT) scan suggested a moderate bilateral posterior slippage of femoral heads; the right and left femoral head-neck angles measured 60 and 52 degrees, respectively. A final diagnosis of bilateral valgus SCFE was established. Consequently, the patient underwent bilateral percutaneous in situ pinning with single cannulated screws. Postoperatively, the patient made an uneventful recovery. At one-year follow-up, hip radiograph showed bilateral atypical narrowing of the joint space and suspected chondrolysis and the physis of both proximal femoral heads were fused. On the right side, the fixating screw was penetrating into the articular surface of the femoral head with some osteoarthritic changes. Considering the patient’s worsening situation, it was decided to perform a revisional surgery. The revisional surgery included the removal of bilateral screws and administration of local steroids and analgesics for pain control. Post-revisional surgery at three months, though the patient was limping with a pelvic tilt, she was able to ambulate with the aid of axillary crutches.

MRI in idiopathic, stable, slipped capital femoral epiphysis: evaluation of contralateral pre-slip

PURPOSE

Early diagnosis and treatment of slipped capital femoral epiphysis (SCFE) is important to prevent slip progression and avoid complications. We sought to determine if MRI findings in patients with unilateral SCFE could indicate 'pre-slip' or predict future SCFE in the contralateral hip.

METHODS

A prospective study evaluated patients with unilateral SCFE over a two-year period. MRI of the asymptomatic hip was performed within the perioperative period. Patients were followed with radiographs until a contralateral slip occurred or until physeal closure. Demographics, clinical stability, severity, posterior slope angle (PSA), modified Oxford Bone Score (mOBS) and patency of the triradiate cartilage were recorded and statistical analysis performed.

RESULTS

In all, 33 of 54 patients with unilateral SCFE were enrolled into the study. In all, 29 (87.8%) had complete follow-up. Five of the enrolled patients (15.2%) developed a sequential slip requiring in situ pinning. Six of 33 (18.2%) patients had positive MRI findings: four of which proceeded to sequential SCFE and two which did not. One sequential slip had a negative MRI. PSA predicted 1/11 sequential slips (sensitivity 9.09%, specificity 81.4%, positive predictive value (PPV) 11.1%, negative predictive value (NPV) 77.8%) and mOBS predicted 5/11 sequential slips (sensitivity 45.5%, specificity 93%, PPV 62.5%, NPV 87%). An open triradiate cartilage was present in 8/11 patients with sequential slips (sensitivity 72.7%, specificity 81.4%, PPV 50%, NPV 92.1%).

CONCLUSION

MRI findings consistent with 'pre-slip' were present in 66.7% of patients who developed a sequential SCFE. Further study on the utility/sensitivity of MRI in predicting sequential SCFE is warranted.

LEVEL OF EVIDENCE

II, diagnostic.

Ultrasonographic Diagnosis of Slipped Capital Femoral Epiphysis

Background

Slipped capital femoral epiphysis (SCFE), a fracture through the physis with resultant slip of the epiphysis, is the most common hip abnormality in adolescents and is a major cause of early osteoarthritis. Plain radiograph is the initial modality used to evaluate patients with painful hip joints. Ultrasonography and magnetic resonance imaging (MRI), which do not involve radiation exposure, have also been used. This case report supports the view that ultrasound can be used as an initial, cost-effective and radiation-free modality for the evaluation of suspected SCFE.

Case Report

A 15-year-old male patient presented with pain in the right hip for 5 days, following a slip and fall accident while playing soccer. The patient was referred to the Department of Radio-diagnosis for ultrasound. A posterior displacement of the femoral head epiphysis with a physeal step was seen on the longitudinal section obtained over the right hip joint region. The anterior physeal step (APS) measured ~3.8 mm on the right side. The distance between the anterior rim of the acetabulum and the metaphysis measured ~20.4 mm on the affected right side and ~23.6 mm on the left side. A plain radiograph in frog leg position showed a widening of the right proximal physis below the right femoral head, with a medial and posterior slip of the right femoral head. A frontal radiograph of the pelvis taken six months before showed a widening of the proximal right femoral physis.

Conclusions

Although MRI appears to be the most sensitive modality for identifying slips early, ultrasound may be used as a cost-effective and radiation-free alternative before proceeding with further evaluation of suspected SCFE, especially considering the demographics of the affected population.

Delay in the Diagnosis of Stable Slipped Capital Femoral Epiphysis

INTRODUCTION

Delays in the diagnosis of stable slipped capital femoral epiphysis (SCFE) is common due to the vague symptomatology and the lack of awareness of this entity by healthcare providers. Delays in the diagnosis of this condition can lead to poor outcomes for the patients. This study was designed to identify factors that contributed to delays in the diagnosis or the treatment of patients with SCFE seen at our institution.

METHODS

A retrospective chart review of patients with the diagnosis of a stable SCFE who had undergone screw stabilization between 1989 and 2010 at our hospital was performed. For each patient, demographic data, the date of initial onset of symptoms, the date of the first visit to the medical provider, the type of provider seen initially (orthopaedic surgeon or not), the date of diagnosis of SCFE, the type of physician who made the diagnosis (orthopaedic surgeon or not), and the date of surgery were recorded. For each patient, the presenting symptom was recorded as hip, thigh, or knee pain. The effect of demographic data, presenting symptoms, and the type of initial provider seen on the delay to diagnosis was studied using 2 Cox models.

RESULTS

A total of 149 patients with 196 stable SCFE were included. The average time from the first physician visit to diagnosis was 94 days in the group seen by a nonorthopaedic provider compared with an average of 2.9 days in the group seen by an orthopaedist (P<0.05). Diagnosis was made in 1 week only in 19% of the group seen by a nonorthopaedic provider versus 97% in the group seen by orthopaedic surgeons. It took significantly longer to be diagnosed with SCFE in patients who presented with initial knee pain (P=0.0097) compared with those who presented with hip pain at the initial visit.

CONCLUSIONS

This study shows a significant delay in the diagnosis of SCFE in the United States, particularly in patients seen by nonorthopaedic providers initially.

LEVEL OF EVIDENCE

Level III-prognostic.

Delayed-onset of slipped capital femoral epiphysis

BACKGROUND

Slipped capital femoral epiphysis in adults is uncommon. The purpose of this study was to report our own four cases (six hips) of slipped capital femoral epiphysis (SCFE) in adulthood and to review the cases reported in the literature. The authors attempted to investigate the various causative underlying disorders and clinical characteristics, treatment, outcome, and complications.

METHODS

We searched for all 22 reported cases of SCFE in adults age 18 years and older via MEDLINE and Google Scholar from 1963 to 2012 without any exception. In doing so, we documented our own four cases, along with seven additional reports that we found in the literature but were not reported by Hu et al. in 2011.

RESULTS

All of 22 cases involved causative pathology: panhypopituitary disorders in 11, hypothyroidism in five, Kallmann syndrome in three, postradiation hypoestrogenism in one, hypogonadotropic hypogonadism as sequel of meningitis in one, and Klinefelter syndrome in one. Eight cases (36 %) involved both hips. The most common treatment modality was internal fixation combined with hormonal replacement therapy. Nineteen hips (63 %) healed well without any complications after fixation of the slipped epiphysis. Avascular necrosis of the femoral head developed in one hip after in situ pin fixation.

CONCLUSION

Awareness of the variety of conditions under which SCFE can occur is an important factor in early diagnosis, especially in slippage at atypical ages. In the adults with SCFE, it is very important to look for bilateral involvement as this occurs in 36 % of cases.

Pain as a Comorbidity of Pediatric Obesity

The purpose of this study was to document the prevalence and characteristics of physical pain in a sample of severely obese children and adolescents. In this retrospective chart review, primary measures included current and past pain, pain intensity, and pain characteristics during a 5-minute walk test. Pain assessments for 74 patients (mean age 11.7 years; 53% female; 41% African American) were conducted by a physical therapist. Past pain was reported by 73% of the sample, with 47% reporting pain on the day of program enrollment. Although average pain intensity was moderate (M = 5.5/10), alarmingly, 42% of those with current pain reported severe pain (6/10 to 10/10). Overall, pain occurred primarily in the lower extremities and with physical activity. Patients reporting current pain had a significantly higher body mass index than those reporting no pain. These findings suggest that pain is common in severely obese youth, and furthermore, that pain should be recognized as a comorbidity of pediatric obesity. Routinely screening severely obese children and adolescents for pain presence and intensity is recommended.

Acetabulotrochanteric distance in slipped capital femoral epiphysis

BACKGROUND

A pathognomonic finding of slipped capital femoral epiphysis (SCFE) is a combination of the decrease in the height of the slipped epiphysis and the position of external rotation and flexion of hip. We believe that decrease in the acetabulotrochanteric distance (ATD) on an anteroposterior (AP) radiograph represents this finding.

MATERIAL AND METHODS

In a retrospective study of 25 consecutive cases of unilateral SCFE, we defined ATD as the distance between a line connecting the superolateral margins of the acetabulae with a second line, parallel to the first line, which goes through the tip of the greater trochanter on each hip and acetabulotrochanteric angle (ATA) as the angle between a line connecting the superolateral margins of the acetabulae with a second line connecting the tip of greater trochanter on each side. The difference in ATD and ATA between both hips in each case was evaluated and their correlation was determined using the Pearson correlation coefficient.

RESULTS

Nineteen cases (76%) showed difference in ATD of > 2 mm and positive ATA divergence of >1 degree. The average difference in ATD was 6.6 mm (range, 0 to 25 mm); the average ATA divergence was 2.4 degree (range, 0 to 5.3 degree).

CONCLUSIONS

Our findings show that the difference in acetabulotrochanteric distance (ATD) between hips is an easy, reliable, and sensitive finding present on an AP radiograph of patients with unilateral SCFE. ATD should be taken into consideration while evaluating AP radiographs of a patient suspected to have SCFE, and further evaluation with lateral hip radiographs should be carried out to confirm the diagnosis.

LEVEL OF EVIDENCE

Level IV.

Slipped capital femoral epiphysis in an adult with panhypopituitarism

Slipped capital femoral epiphysis usually occurs in children going through a pubertal growth spurt, possibly because the immature proximal femoral physis is unable to bear the shear stress. It commonly occurs in adolescents between 10 and 16 years. Slipped capital femoral epiphysis in adults is uncommon, with only 10 cases reported in the literature. This article presents a case of a 29-year-old man with craniopharyngioma diagnosed when he was 19. He underwent surgery with subtotal tumor excision and postoperative radiotherapy, but received no further treatment for the panhypopituitarism concomitant with the tumor. He reported sudden onset of left hip pain after riding a bicycle and underwent surgical fixation 5 days later. He also underwent hormone replacement therapy, including prednisolone, thyroxin, desmopressin, and testosterone, and regular clinical follow-up. His hip function recovered with a painless gait. At 18-month follow-up, neither osteonecrosis nor contralateral slipped capital femoral epiphysis was noted. Furthermore, bilateral proximal femoral physes were also closed. For stable slippage as in this case, in situ pinning fixation is a commendable method. A high index of suspicion of endocrinal disorder and proper management are essential for successful treatment of adult slipped capital femoral epiphysis.

Prognostic significance of stability in slipped upper femoral epiphysis: a systematic review and meta-analysis

OBJECTIVE

To examine associations of major complications after surgical treatment of slipped upper femoral epiphysis (SUFE) with condition- and treatment-related risk factors.

STUDY DESIGN

This systematic review and meta-analysis of observational studies used an electronic literature search of Embase and Medline supplemented by a manual search of bibliographies. The studies enrolled children and adolescents with SUFE, defined stable and unstable disease, and reported at least 3 primary endpoints: avascular necrosis (AVN), chondrolysis, and reoperation. Random-effects meta-regression analysis was performed when possible.

RESULTS

The weighted risk for AVN, derived from intercept-only meta-regression, was estimated as 5.3% (95% confidence interval [CI], 3.4%-7.2%). Patients with unstable slips had a 9.4-fold greater risk of developing AVN. Instability proved to be an independent predictor for AVN. The weighted risk of chondrolysis was 0.8% (95% CI, 0.2%-1.4%), associated with unstable slips and osteotomies. The risk of reoperation was estimated at 5.5% (95% CI, 1.7%-9.3%). Loss of fixation was the primary reason for reoperation.

CONCLUSIONS

Current evidence indicates that unstable slips are at a significantly higher risk for AVN than stable slips, regardless of the attempted surgical approach. Little clinical information is available regarding chondrolysis and reoperation in relation to the stability of the physis.

Slipped upper femoral epiphysis--a case of a 'dodgem hip'

A 15-year-old male patient of slim habitus presented three times over 3 days to the emergency department. Four weeks prior to the first attendance, he apparently injured his left knee in a sudden jolt whilst going on a 'bumper car' (dodgems) at a funfair. Since this incident, he had walked with a limp due to the pain in his left knee. He had sustained a slipped upper femoral epiphysis (SUFE) through this unusual mechanism of injury.

Slipped capital femoral epiphysis update

PURPOSE OF REVIEW

Slipped capital femoral epiphysis (SCFE) is the most common adolescent hip condition. Its importance lies in its high morbidity if not diagnosed and treated in its early stages, not only in childhood but also as a cause of osteoarthritis in adulthood. This article highlights key diagnostic tools and optimal treatment plans for SCFE.

RECENT FINDINGS

SCFE involves displacement between the proximal femoral neck and the femoral head at the level of the open physis, with biomechanical and biochemical factors implicated. Acute major trauma is rarely involved; a gradual onset of symptoms and deformity is more common. Patients with unstable SCFE are in severe pain and unable to bear weight. SCFE occasionally is associated with endocrine or metabolic abnormality (hypothyroidism, panhypopituitarism and renal rickets). On physical examination, limited internal rotation of the affected hip is usual; obligatory external rotation of hip in flexion is classic. Diagnosis is confirmed on anteroposterior and frog-leg lateral radiographs of both hips. Treatment is surgical, with stabilization across the physis by in-situ pinning being the gold standard.

SUMMARY

Prompt diagnosis and timely surgical treatment usually lead to excellent long-term results with minimal morbidity. It is crucial to recognize that groin pulls are very rare in adolescents. Children with suggestive groin symptoms should have hip anteroposterior and frog-leg lateral radiographs to rule out the much more common SCFE.

Slipped Capital Femoral Epiphysis as a Complication of Growth Hormone Therapy

Slipped capital femoral epiphysis (SCFE) is a rare complication of growth hormone (GH) therapy. Here, we report three patients who developed SCFE during GH therapy. The first two patients had hypopituitarism and had started GH therapy at the age of 15 years 6 months and 13 years 9 months, respectively. SCFE developed 4 years and 1 year after GH therapy, respectively. The third patient had Prader-Willi syndrome with obesity and hypogonadism and began GH therapy at the age of 12 years and 11 months. SCFE developed 2 months after starting GH therapy. Pain over the hip joints or over the knees is an early sign of SCFE. Despite recommendation, none of the three patients continued GH therapy. A high index of suspicion during GH therapy in patients at high risk of SCFE is important for early diagnosis and appropriate management.

Delay in diagnosis of slipped capital femoral epiphysis

OBJECTIVE

Delay in diagnosis of slipped capital femoral epiphysis (SCFE) has important implications in terms of slip severity and long-term hip outcome. The purpose of this study was to identify predictors of delay in the diagnosis of SCFE.

METHODS

A review of 196 patients with SCFE was performed. The primary outcome measure was delay from onset of symptoms to diagnosis. Covariates included age, gender, side, weight, pain location, insurance status, family income, slip severity, and slip stability. Delay in diagnosis was not normal in distribution; therefore, nonparametric univariate and multivariate analyses were performed.

RESULTS

The median delay in diagnosis was 8.0 weeks. There was a significant relationship between delay in diagnosis and slip severity (<30 degrees : 10.0 weeks; 30 degrees to 50 degrees : 14.4 weeks; >50 degrees : 20.6 weeks). There were no significant associations between delay in diagnosis and covariates of age, gender, side, and weight. There were significant associations between longer delay in diagnosis and covariates of knee/distal-thigh pain versus hip/proximal-thigh pain (6.0 vs 15.0 weeks), Medicaid coverage versus private insurance (12.0 vs 7.5 weeks), lower family income, and stable slips versus unstable slips (8.0 vs 6.5 weeks). Controlling for the other covariates, knee/distal-thigh pain, Medicaid insurance, and stable slips remained significant independent multivariate predictors of delay in diagnosis.

CONCLUSIONS

Patients who present with primarily knee or distal-thigh pain, patients with Medicaid coverage, and patients with stable slips have longer delays in diagnosis of SCFE. Focused intervention programs to reduce the delay in diagnosis of SCFE should emphasize patients with knee/thigh pain and patients with Medicaid coverage.

Orthopedic pitfalls in the ED: slipped capital femoral epiphysis

Slipped capital femoral epiphysis (SCFE), though a relatively common disorder, is frequently missed on initial presentation. Symptoms can be vague, the physical examination unrevealing, and radiographic abnormalities subtle. Prompt diagnosis of SCFE is important, however, to improve clinical outcome. The emergency physician needs to remain vigilant for this diagnosis to avoid this orthopedic pitfall. This article examines the clinical presentation, diagnostic techniques, and management options applicable to the emergency physician in the treatment of SCFE.

Seasonal variation of slipped capital femoral epiphysis

During the 18-year period 1980-1997, 1103 patients were treated as in-patients for slipped capital femoral epiphysis (SCFE) in Scottish hospitals. This paper reports a significant seasonal variation, especially in male patients, with an excess admitted in the autumn. Examining the physiological seasonality of the monthly increment of growth in height and weight in childhood, we hypothesised that these physiological rhythms, while not pathogenetic, may be responsible for the timing of the seasonal features of SCFE. Previously published studies suggest that the average time between first symptoms and diagnosis is 3 to 5 months. The condition may start with the spring peak in growth and become more symptomatic with the autumn peak in weight. In conclusion, we report a new epidemiological finding, but, in accordance with other studies, we cannot provide a certain aetiological explanation. The timing, but not the pathogenesis, of admission to hospital for a SCFE might be related to the timing in the year of seasonal increments of height in spring and weight in autumn. It is tempting to draw attention to associations with environmental features. For example, in autumn there is the most rapid annual fall in temperature, and the hours of darkness are increasing from the autumn equinox to the winter solstice. However, there is no reason to conclude that these associations have anything to do with aetiology.

Magnetic resonance imaging as the primary imaging modality in children presenting with acute non-traumatic hip pain

The role of magnetic resonance imaging (MRI) in children presenting with acute non-traumatic hip pain was evaluated prospectively. Hip MRI was performed in addition to standard investigations (arthrosonography +/- hip radiographs) in 50 children presenting to the accident and emergency department of a paediatric hospital. MRI was performed on an open 0.23T system and comprised gradient echo T1 weighted coronal, fast spin echo T2 weighted coronal and inversion recovery spin echo (IRSE) axial sequences. Diagnostic quality MRI examinations were obtained in 94% of children. The IRSE sequence was the most reliable at determining underlying disorder (p<0.002). Interobserver agreement on the MRI examinations was very good with unweighted kappa value of 0.89, 95% confidence intervals 0.79, 0.99. Sensitivity of MRI was 0.79 (0.68, 0.90, specificity 1.00 (0.89, 1.00), accuracy 0.81 (0.70, 0.92), PPV 1.00 (0.89, 1), NPV 0.36 (0.25, 0.47). Sensitivity of standard imaging was 0.70 (0.54-0.86), specificity 0.57 (0.41, 0.73), accuracy 0.72 (0.56, 0.88), PPV 0.91 (0.75, 1.00), NPV 0.24 (0.08, 0.40). MRI correctly identified all seven children with serious underlying disorder whereas conventional imaging correctly diagnosed only two. Pelvic musculoskeletal infection was associated with the combination of marked alteration in signal in tissues adjacent to a symptomatic hip and an erythrocyte sedimentation rate of >20 mm 1st h (p<0.0001). In conclusion, MRI is a practical, well accepted and accurate non-invasive imaging technique in children presenting with acute non-traumatic hip pain. Combined with inflammatory markers MRI can be used to determine those children who require aggressive management. Where it is available, MRI is the imaging modality of choice in this condition.

Uncommon causes of anterior knee pain: a case report of infrapatellar contracture syndrome

The uncommon causes of anterior knee pain should always be considered in the differential diagnosis of a painful knee when treatment of common origins become ineffective. A case is presented in which the revised diagnosis of infrapatellar contracture syndrome was made after noting delayed progress in the rehabilitation of an active female patient with a presumed anterior horn medial meniscus tear and a contracted patellar tendon. The patient improved after the treatment program was augmented with closed manipulation under arthroscopy and infrapatellar injection of both corticosteroids and a local anesthetic. Infrapatellar contraction syndrome and other uncommon sources of anterior knee pain, including arthrofibrosis, Hoffa's syndrome, tibial collateral ligament bursitis, saphenous nerve palsy, isolated ganglions of the anterior cruciate ligament, slipped capital femoral epiphysis, and knee tumors, are subsequently discussed. Delayed functional advancement in a rehabilitation program requires full reassessment of the patient's diagnosis and treatment plan. Alternative diagnoses of knee pain are not always of common origins. Ample knowledge of uncommon causes of anterior knee pain is necessary to form a full differential diagnosis in patients with challenging presentations.