Common overuse injuries in the young athlete

Pediatric overuse injury is a common complaint presenting to pediatricians. Overuse injury can affect the soft tissues or bone, and results from an imbalance between training and load to the tissues and recovery time. In the skeletally immature athlete, physeal and apophyseal tissue is particularly vulnerable to overuse resulting in different patterns of injury compared to adults. Awareness of age-dependent patterns of overuse is necessary for proper recognition, treatment, and prevention of injury. This article reviews the most common pediatric overuse injuries with emphasis on risk factors, diagnosis, and treatment. Guidelines for prevention are included, as this is the key component for successful management of overuse injury in pediatric athletes.

Traumatic epiphysiolysis of the proximal femur

PURPOSE OF THE STUDY

Several former studies show the treatment of slipped epiphysis of the femoral head (SEFH). Its reason is rather unknown. On the other hand the rare traumatic SEFH takes place due to a real accident. According to the literature these injuries are treated like chronic SEFHs. The aim of this study is to show the differences in pathology and treatment of an acute traumatic SEFH in relationship to the chronic SEFH.

PATIENTS AND METHODS

In 8 patients dislocated traumatic SEFHs were reduced anatomically and stabilized by the means of 3 to 4 Kirschner- (K-) wires or two cancellous screws. Each patient got a plaster-cast fixation for about 6 weeks of the ipsilateral hip and leg and was mobilized with two crutches and partial weight bearing for 12 weeks. The implants were removed 24 weeks after surgery. Four patients with not dislocated SEFHs were immobilized or mobilized with two crutches without weight bearing according to their pain sensation. The final examination of both groups took place 2 Vz to 15 years after the initial treatment.

RESULTS

Four patients primarily under 10 years of age showed no or minimal radiological signs of a dislocated femoral head and were without any further inconvenience--the suspected SEFHs revealed as hip contusions. 8 children aged 10 years or older at the time of trauma were treated by closed reduction and internal fixation. Complications occurred in three cases--one necrosis of the femoral head because of a perforating K-wire, one subtrochanteric femur fracture after implant removal of a prophylactically stabilized contralateral femoral head and one minimally dislocated femoral head after postoperative too early full weight bearing.

DISCUSSION

The traumatic SEFH is very different to the chronic one regarding the pathology and acute treatment. Technical challenges must be solved. Unilateral K-wiring or screwing for 24 weeks and reduced weight bearing for the first 12 weeks after surgery is a sufficient way of treatment of the traumatic SEFH.

CONCLUSIONS

In the case of a traumatic SEFH it needs to be reduced anatomically and stabilized by surgical means in the acute phase. A prophylactic stabilization of the opposite intact side is usually not required.

[Traumatic distal humerus epiphysiolysis in a newborn child]

Traumatic distal humerus epiphysiolysis (TDHE) is a rare injury in infants with an incidence of about 1:35,000 births. It is primarily a birth injury, but it is also seen in cases of battered child syndrome. Because of its rare occurrence and the diagnostic difficulties, the lesion may be overlooked or misdiagnosed on initial presentation. The diagnosis is made on the basis of a high index of suspicion, clinical signs and symptoms and awareness of radiological changes. Traumatic humeral dislocation will produce the same radiological picture as TDHE and is consequently a common, incorrect initial diagnosis. We present a case of TDHE as a birth injury.

[Proximal tibial growth plate trauma in childhood and options for its management]

AIM

Traumas to the proximal tibial epiphyseal growth plate account for less than 2% of all physeal injuries, therefore, it may cause diagnostic or therapeutic difficulties. The authors studied a group of patients treated in the Clinic of pediatric surgery, orthopedics and traumatology of the Brno Faculty Hospital (FN Brno) during past 11 years, in order to assess its treatment outcomes and complication rates.

METHODOLOGY

Based on the Salter-Harris (SH) classification, the studied patients with proximal tibia epiphyseolyses were assigned to groups using the following criteria: type of epiphyseolysis and treatment approach, and the authors identified associated complications in individual patients. The follow up assessment of the treatment course and results were performed for each of the groups. The studied parametres included: fixation duration, duration of subsequent rehabilitation care, knee joint mobility and complication rates (angulation, limb shortening, skeletal porosis and eventual reoperation).

RESULTS

The studied complications were recorded in 2 subjects in the undislocated epiphyseolysis group treated conservatively, and a single complication was recorded in the traumatic fragment dislocation group. Out of the total of 19 patients, complications were recorded in 3 subjects (16%) and the remaining 16 patients (84%) had no complications or posttraumatic effects recorded.

CONCLUSION

The study results correspond to the literature data. Therefore, minimum complication rates and high treatment success rates using standard treatment procedures were demonstrated.

Anticonvulsant drug-induced rickets and multiple slipped epiphyses in a child treated non-operatively: a case report

The clinical and radiographic presentation of a child with spastic tetraplegia, anticonvulsant drug-induced rickets, borderline hypothyroidism and multiple slipped epiphyses is described. While the metabolic abnormalities were being treated, the parents denied surgical treatment and have been non-compliant with bracing of the wrist, ankle and knee deformities. By two years of medical treatment, rickets had resolved and the growth plates of the lower limbs' joints had closed. Non weight-bearing, gentle physiotherapy and bracing led to good results in the hip, ankle and wrist joints and to unacceptable residual valgus angular and rotational deformity of the right knee. Severely handicapped paediatric patients with metabolic bone disorders, non-compliant with bracing and with co-existent soft tissue contractures, are probably not good candidates for conservative treatment of severe angular limb deformities. However, non-operative treatment of minimal or moderate slippage of the proximal femoral epiphysis (as well as other major epiphyses) can lead to good results.

Little Leaguer's shoulder (proximal humeral epiphysiolysis): MRI findings in four boys

BACKGROUND

Shoulder pain is a common problem among adolescent athletes. A possible cause of such pain that can be diagnosed on MRI is a stress injury to the proximal humerus known as Little Leaguer's shoulder (proximal humeral epiphysiolysis).

OBJECTIVE

Our objective was to describe the MRI appearance of Little Leaguer's shoulder.

MATERIALS AND METHODS

Four patients (all boys; age range 11-15 years; median 13 years) with clinical, plain radiographic, and MR imaging findings of Little Leaguer's shoulder were studied retrospectively.

RESULTS

MRI demonstrated focal physeal widening in all four boys with extension of physeal signal intensity into the metaphysis on T1-weighted and gradient echo coronal and sagittal sequences. T2-weighted sequences were of limited use in demonstrating the physeal widening, which is critical to the diagnosis. Abnormal high T2-signal intensity was seen in the metaphysis adjacent to the focal physeal widening in all the boys.

CONCLUSION

Focal extension of normal physeal T1-weighted and gradient echo signal intensity into the adjacent metaphysis is a sign of stress injury in the proximal humeral physis (Little Leaguer's shoulder). Children should suspend the offending sport to allow healing.

Potential influence of hormones in the development of slipped capital femoral epiphysis: a preliminary study

The potential influence of hormonal imbalance on the development of slipped capital femoral epiphysis was assessed through a prospective clinical study. The serum levels of T3, T4, thyroid-stimulating hormone, testosterone, estradiol, dehydroepiandrosterone-sulfate, follicle-stimulating hormone, luteinizing hormone, human growth hormone, adrenal cortex hormone and cortisol were evaluated in seven boys and seven girls. Forty-three out of 154 hormonal determinations (27.9%) were abnormal. The results showed increased incidence of pathological values mainly in the levels of follicle-stimulating-hormone, luteinizing-hormone and testosterone. No patient had clinical findings of endocrinopathy. A (possibly) temporary hormonal disorder may play a potentially significant role in the development of slipped capital femoral epiphysis.

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.

Proximal femoral epiphysiolysis during reduction of hip dislocation in adolescents

Traumatic hip dislocation is an uncommon injury in children. The urgency of closed reduction to prevent possible osteonecrosis may present some pitfalls. Adolescents with open proximal femoral physis may have sustained trauma to the physis at the time of dislocation that can lead to displacement of the epiphysis during the reduction maneuver. The purpose of this study is to report 5 cases with this complication and discuss potential etiology and management. All of the 5 patients were between 12 and 16 years old and underwent closed reduction under conscious sedation. Epiphysiolysis of the femoral head was diagnosed after reduction in all 5 patients. Every patient underwent emergent open reduction and internal fixation of the femur and open hip reduction. Avascular necrosis was identified in all 5 patients within 3 to 15 months postinjury. If there is any suspicion of associated physeal injury or if there is any physeal instability noted under fluoroscopy, an open reduction is recommended in the operating room under radiograph guidance to prevent displacement.

Pseudohypoparathyroidism: a rare cause of bilateral slipped capital femoral epiphysis

Pseudohypoparathyroidism (PHP) type 1b is a rare childhood disorder characterized by renal resistance to parathyroid hormone (PTH) resulting in biochemical hypoparathyroidism but with skeletal sensitivity to PTH. We describe a patient with PHP type 1b who we believe is one of the youngest reported patients with bilateral slipped capital femoral epiphyses (SCFE).

Slipped capital femoral epiphysis: the importance of early diagnosis

Slipped capital femoral epiphysis typically occurs in adolescents. Presentation may include limp or vague pain in the hip, thigh or knee. Knee pain, in particular, is a common complaint among adolescents and may be due to patello-femoral syndromes, Osgood-Schlatter disease, patellar tendonitis, or chondromalacia patella, to name a few. However, it is vital to remember that the complaint of knee pain may be present because of referred pain from pathology at the hip. Every child presenting with a complaint of hip, thigh or knee pain must undergo a hip examination. Likewise, a "groin pull" is exceedingly rare in children and must be a diagnosis of exclusion. Any child with complaints of hip, thigh, or knee pain, or physical examination findings of out-toeing, decreased internal rotation, or obligate external rotation with flexion, should be presumed to have SCFE until proven otherwise. There is a high rate of delay in diagnosis of SCFE, which leads to opportunities for progression of deformity, which in turn leads to increased risk of arthritis. Delay in diagnosis also may allow a stable SCFE to become an unstable one, with a much higher risk of development of AVN. When suspected, the diagnosis is confirmed with x-rays (AP and frog-lateral of the pelvis). Therefore, a high index of suspicion for this disorder, and the attainment of appropriate radiographs, should allow for prompt diagnosis and referral for treatment. Treatment is urgent and surgical. Early diagnosis and proper treatment are the mainstays of prevention of adverse sequelae.

[Proximal tibial epiphysiolysis in a young gymnast due to hyperflexion trauma]

The authors present an unusual case of upper tibial epiphysiolysis due to hyperflexion trauma. The patient was operated on by removal of interposed periosteum and fixation by crossed Kirchner wires. Knowledge of the mechanism of trauma and the direction of the force of the trauma is essential to the planning of the surgical approach and awareness of possible complications.

Biomechanics of the shoulder in youth baseball pitchers: implications for the development of proximal humeral epiphysiolysis and humeral retrotorsion

BACKGROUND

The effects of repetitive throwing on the shoulders of developing athletes are not well understood because of the paucity of data describing the biomechanics of youth pitchers and the plasticity of the developing skeleton.

HYPOTHESIS

The direction and magnitude of the stresses that exist at the proximal humeral physis during the fastball pitching motion are consistent with the development of proximal humeral epiphysiolysis (Little League shoulder) and/or humeral retro-torsion.

STUDY DESIGN

Descriptive laboratory study.

METHODS

A total of 14 elite youth baseball pitchers (mean age, 12.1 +/- 0.4 years) were filmed from the front and dominant side while throwing fastballs in a simulated game. The net force and torque acting on the humerus throughout the throwing motion were calculated using standard biomechanical techniques.

RESULTS

The external rotation torque about the long axis of the humerus reached a peak value of 17.7 +/- 3.5 N.m (2.7% +/- 0.3% body weight x height) just before maximum shoulder external rotation. A shoulder distraction force of 214.7 +/- 47.2 N (49.8% +/- 8.3% body weight) occurred at, or just after, ball release.

CONCLUSION

Shear stress arising from the high torque late in the arm-cocking phase is large enough to lead to deformation of the weak proximal humeral epiphyseal cartilage, causing either humeral retrotorsion or proximal humeral epiphysiolysis over time. The stresses generated by the external rotation torque are much greater than those caused by distraction forces generated during the pitching motion of youth baseball pitchers.

CLINICAL RELEVANCE

The motion of throwing fastballs by youth baseball pitchers results in force components consistent with proposed mechanisms for 2 clinical entities.

[Slipped capital femoral epiphysis and overweight]

The slipped capital femoral epiphysis (SCFE) is defined as a nontraumatic epiphyseal separation and slipping of the proximal femoral epiphysis, which usually occurs during the adolescent growth spurt. Slipping of the upper femoral epiphysis may be classified as acute, chronic, and acute on chronic. The etiology of the disease is still not fully understood but seems to be multifactorial. The typical SCFE during puberty has to be differentiated from the atypical form, which may be associated with an endocrinological disorder or with its therapy. The typical SCFE may be found in male patients, with increased height and weight. It is likely that the growth rate is slightly accelerated before slippage. Obesity is often associated with a decreased femoral anteversion accounting for abnormal mechanical shear forces at the growth plate. SCFE is treated surgically. Surgical methods are administered according to the degree of disease. Because of possible alterations of blood supply to the femoral head, acute SCFE is an emergency. Following SCFE, complications such as chondrolysis and avascular necrosis are feared.

Surgical treatment of the severe sequelae of infantile septic arthritis of the hip

We retrospectively reviewed 45 hips in 43 patients with severe sequelae of infantile septic arthritis of the hip to compare the efficacy of various hip reconstructive and salvage surgeries, and to propose an algorithmic treatment protocol for the different types. Ten hips were classified as Choi Type IIIA, three as Type IIIB, 14 as Type IVA, and 18 as Type IVB sequelae. A total of 78 hip surgeries and 18 limb-length equalizations (three contralateral femoral epiphysiodesis and 15 ipsilateral femoral and/or tibial lengthenings) were done. The first surgical reconstructions were done at an average age of 5.9 years (range, 1.1-14.8 years), with a 9.5-year average followup. Type IIIA hips had better functional results than the other types. In Type III hips, early realignment osteotomy of the proximal femur or bone-grafting of the pseudarthrosis was indicated. In Type IVB hips, satisfactory results were observed in only five of 10 hips treated by trochanteric arthroplasty compared with satisfactory results in all four hips treated by Ilizarov's hip reconstruction osteotomy. The latter operation seems to be better indicated in older patients with Type IVB hips, or with Type IVA hips in which previous reconstructive surgery was unsuccessful.

[Epiphysiolysis capitis femoris caused by a repeat minor trauma]

We discuss the case of a 14-year-old boy who, after two episodes of mild recurrent sports trauma, presented with restricted mobility of the right hip due to substantial pain. Radiography revealed an acute slipped capital femoral epiphysis affecting the right femoral head. We report on the successful emergency osteosynthesis, and follow-up. On the basis of the current literature, we also discuss the clinical course of this lesion.

Slipped capital femoral epiphysis in patients with Down syndrome

The authors report their experience with eight patients (11 hips) with Down syndrome who sustained a slipped capital femoral epiphysis (SCFE). Six patients were diagnosed with hypothyroidism. All patients were greater than the 85th percentile for body mass index. Initial treatment was by in situ pinning in all hips. Six of the 11 slips progressed, 2 had collapse consistent with avascular necrosis, and 1 developed collapse secondary to joint sepsis and osteomyelitis. Additional surgery was necessary on seven hips. Four of eight hips followed until maturity had substantial femoral head deformity. Three of these patients had a noticeable limp and pain. Treatment of SCFE in patients with Down syndrome is difficult and the prognosis is guarded. These patients should be screened for hypothyroidism.

Atypical slipped capital femoral epiphysis after radiotherapy and chemotherapy

Atypical slipped capital femoral epiphysis after radiotherapy and chemotherapy is uncommon. Only 32 cases have been reported in the literature. Because patients may have slippage at atypical ages, we report two cases of slipped capital femoral epiphysis in children and review the 32 cases previously reported to heighten clinicians' awareness of this condition in patients who have received radiation and chemotherapy for pelvic tumors. The controversy over prophylactic pinning of the uninvolved hip in radiotherapy-associated slipped capital femoral epiphysis is unresolved. It may be justifiable to fix the nonslipped epiphysis if possible prodromal signs of abnormal radiographic findings are detected. Because radiotherapy and chemotherapy were used in the two children reported, it is not possible to state whether one or both forms of treatment were responsible for the atypical slipped capital femoral epiphysis.

Slipped capital femoral epiphysis: etiology and treatment

Progression of slip is apt to cause complications including osteonecrosis and osteoarthritis. Such complications result in a poor prognosis for the joint. Therefore, to diagnose slipped capital femoral epiphysis (SCFE) while it is still mild is important to avoid complications as well as to prevent further slippage. In Japan, as the number of obese patients increases, obesity seems to be involved in the onset of slip both biomechanically and endocrinologically. We need to take care of obese children as they comprise a reservoir for SCFE patients. For severe slip cases, treatment is difficult owing to significant deformity of the femoral head with or without such complications as osteonecrosis and osteoarthritis. Transtrochanteric anterior rotational osteotomy is a promising option for preventing further slippage as well as to improve the congruity of the joint.

Medial clavicular epiphysiolysis in children: the so-called sterno-clavicular dislocation

We retrospectively reviewed six pediatric cases of medial clavicular injury, i.e., epiphyseal separation (Salter/Harris type I or II injury), diagnosed between 1993 and 1997. The clavicular metaphysis was displaced posteriorly in three cases and anteriorly in three. On conventional radiographic views the diagnosis was initially missed in two of three retrosternal dislocations. A special X-ray projection (described by Heinig) or computed tomography (CT) permitted correct diagnosis. Anterior dislocations were immediately and correctly diagnosed. Closed reduction successfully treated retrosternal displacement in two of the three patients. The third patient needed open reduction and internal fixation. Open reduction and internal fixation had to be performed in all three patients with anterior displacement. Follow-up assessment showed perfect functional results in all cases. Direct visualization during open reduction, which was necessary in four of six cases, yielded clear evidence that the so-called sternoclavicular dislocation in children and young adults is, in fact, a fracture of the medial growth plate with posterior or anterior displacement of the metaphysis.

Body mass index and slipped capital femoral epiphysis

Body mass index (BMI) as a predictor of slipped capital femoral epiphysis (SCFE) was studied. A total of 26 adolescent patients had complete annual height and weight measurements taken from birth to onset of slippage. These values were compared with those of the normal adolescent population. Patients with SCFE showed statistically higher BMI during growth than normal developing children. BMI gives more accurate data on body build than height and weight alone and may be a useful tool for evaluating risk factors in SCFE.

Gigantism associated with slipped capital femoral epiphysis

The etiology of slipped capital femoral epiphysis (SCFE) is unknown, though hormonal as well as mechanical factors have been implicated. We report a case of gigantism who presented with SCFE. This case provides an insight into the genesis of SCFE, which in this case was related to growth hormone excess and sex-hormone deficiency.

Outcome of slipped capital femoral epiphysis in renal osteodystrophy

The cases of renal osteodystrophy-associated slipped capital femoral epiphysis in 11 consecutive patients were reviewed. Nine patients had bilateral involvement, totaling 20 hips. The mean age at presentation was 10.6 years. Slip location was physeal in 13 and metaphyseal in seven hips. All patients had prompt medical treatment of their bone disease, and nine patients underwent surgical stabilization. Fixation consisted of multiple custom-machined Steinmann pins that were smoothed distally but threaded proximally, allowing continued proximal femoral growth. The mean radiographic and clinical follow-up was 5.7 years and 9.1 years, respectively. Slips stabilized in 14 of 16 operated hips (88%), whereas one patient with inadequate renal disease control had slip progression requiring subsequent subtotal parathyroidectomy and repeat fixation. Combined medical management and surgery with custom-machined pins prevented slip progression while allowing continued physeal growth.

Slipped capital femoral epiphysis following contralateral infantile Blount's disease

Slipped capital femoral epiphysis (SCFE) and Blount's disease are reported to have a common etiology, but there is only one report describing two cases in which adolescent Blount's disease coexisted with SCFE. In this article, we describe a case of SCFE following contralateral infantile Blount's disease in an 11-year-old boy. This report is the first known case of SCFE associated with infantile Blount's disease. In this patient, pelvic tilt caused by leg length discrepancy associated with infantile Blount's disease and possible general weakness of the growth plate may be related to the occurrence of SCFE.

Clinical characteristics of children with atypical and idiopathic slipped capital femoral epiphysis: description of the age-weight test and implications for further diagnostic investigation

SUMMARY

Slipped capital femoral epiphyses (SCFEs) can be idiopathic or atypical (associated with renal failure, radiation therapy, and endocrine disorders). The demographics of 433 children (285 idiopathic, 148 atypical) with 612 SCFEs were studied to define predictors of atypical SCFEs. Multiple logistic regression analysis showed that age and weight were predictors. For two patients of equal weight, those younger than 10 or older than 16 years of age were 4.2 times more likely to have an atypical SCFE; for two patients of equal age, those <50th percentile weight were 8.4 times more likely. The age-weight test was defined as negative when age younger than 16 years and weight > or = 50th percentile and positive when beyond these boundaries. The probability of a child with a negative test result having an idiopathic SCFE was 93%, and the probability of a child with a positive test result having an atypical SCFE was 52%. An evaluation of the child's age and weight is useful when considering the cause of an SCFE.

[Diagnostic image (35). Epiphysiolysis of the knee due to renal osteodystrophy]

A 14-year-old boy with long-standing renal insufficiency presented with a virtually symptom free slipped epiphysis of the right knee.

Epiphysiolysis of the hip: relationship between etiopathogenesis and hormone status

The authors present a review of the literature on the etiology of epiphysiolysis of the hip and an original study on the hormone status of these patients. By examining eleven values including hormones, vector proteins, and hormonal transport, the authors related the data obtained to the anagraphical age of the patient, to his or her skeletal age, to the development of sexual features, and to the radiologic evidence of pathology. In light of the results obtained, despite the fact that the study only included 23 patients, the modified equilibrium between SHBG and Somatomedin C, would seem to lead to an accelerated turnover in the growth plate. The increase in BMI directly correlated with low levels of SHBG is also an indication of the increase in body weight that certainly contributes to slippage of the femoral head.

Salter-Harris type II fractures of the capital femoral epiphysis

Salter-Harris type II fractures of the capital femoral epiphysis have not been previously documented. The authors have treated three patients who sustained four such fractures. One child had a recurrent fracture two years after the first had healed satisfactorily. Two fractures were treated by spica cast immobilization, one fracture by closed reduction and internal fixation, and the other fracture healed without treatment. No patient developed avascular necrosis or other complications. Two of the children had an association with idiopathic slipped capital femoral epiphysis. An etiologic relationship with slipped capital femoral epiphysis, if any, is uncertain.

Delayed separation of the capital femoral epiphysis after an ipsilateral transcervical fracture of the femoral neck

A displaced transcervical fracture of the femoral neck in a three-year-eight-month-old boy was fixed with two screws, which did not cross the growth plate. When he resumed walking five weeks after the injury, a delayed separation of the capital femoral epiphysis occurred. The displaced epiphysis was reduced and fixed with three unthreaded pins. In spite of disruption of the femoral neck at two sites, avascular necrosis of the femoral head did not occur. This was confirmed by two sequential isotope scans. Delayed epiphyseal separation after the femoral neck fracture and the preservation of the vascularity of the epiphysis in this case are both very unusual.

Epiphyseal separations after neonatal osteomyelitis and septic arthritis

Complete separation of an epiphysis is a rare complication of neonatal osteomyelitis and septic arthritis. We report two cases of pathologic epiphyseal separation after neonatal osteomyelitis, involving the distal and proximal femoral epiphyses with a follow-up of 2 and 7.5 years, respectively. Birth trauma, scurvy, and nonaccidental injury should be considered in the differential diagnosis of pathologic epiphyseal slip. The pitfalls in diagnosis are many, and plain radiograms of unossified epiphyses are often misleading. A high index of suspicion and the use of imaging modalities are useful in making an early diagnosis of epiphyseal slip. The optimal treatment is controversial, and the long-term prognosis is uncertain. The potential for recovery appears to be excellent, provided an early diagnosis is made and prompt treatment by anatomic reduction of the displaced epiphysis is instituted.

[Periostal interposition in epiphysiolysis, diagnosed by ultrasound]

Musculoskeletal ultrasound is a rapidly expanding diagnostic field. High frequency transducers with high spacial resolution make it possible to demonstrate superficial soft tissue structures such as tendons, muscles, ligaments and even, under certain circumstances, fractures and periosteum. A case is presented where ultrasound clearly visualised periostal interposition in a distal tibial epiphysiolysis in an eight year-old boy, and some aspects of ultrasound in musculo-skeletal imaging are discussed.