Femoral neck fracture secondary to in situ pinning of slipped capital femoral epiphysis: a previously unreported complication

Two patients developed femoral neck fractures as a complication of in situ pinning for slipped capital femoral epiphysis (SCFE) by surgeons who each used a cannulated screw system. Both patients exhibited recurrent hip pain, femoral neck fracture, and coxa vara after asymptomatic postoperative intervals of 2 and 6 months, respectively. The fracture in one patient healed with weight relief alone: the other persisted, requiring a vascularized pedicle bone graft. Bone biopsy at surgery disclosed avascular necrosis (AVN). Based on preliminary studies of heat production during reaming, we speculate that these fractures developed through areas of AVN secondary to thermal injury.     

Factors influencing the development of osteonecrosis in patients treated for slipped capital femoral epiphysis

BACKGROUND: Osteonecrosis is a serious complication of the treatment of slipped capital femoral epiphysis. The purpose of the present study was to identify factors influencing the development of osteonecrosis. METHODS: Two hundred and forty patients who had been treated for slipped capital femoral epiphysis between 1965 and 1999 were retrospectively evaluated. Treatment included stabilization with a spica cast or fixation with one to four pins or screws. Radiographs that had been made at the time of presentation, before and after the operation, and at consecutive follow-up examinations were reviewed. Osteonecrosis was defined retrospectively on the basis of radiographic evidence of sclerosis and collapse of the femoral head. The risk of development of osteonecrosis was correlated with various clinical and radiographic parameters. RESULTS: All twenty-one patients in whom osteonecrosis developed had presented with an unstable slipped capital femoral epiphysis. None of the 204 patients who had presented with a stable slipped capital femoral epiphysis, regardless of grade, had development of osteonecrosis. In the group of patients who had presented with an unstable slipped capital femoral epiphysis, the risk of development of osteonecrosis increased with the severity (grade) of the slip. Osteonecrosis was more likely to develop in patients who had been treated with multiple pins than in those who had been treated with a single cannulated screw. CONCLUSIONS: Patients who have a stable slipped capital femoral epiphysis are not at risk for the development of osteonecrosis when treated with pinning in situ. Patients who have an unstable slipped capital femoral epiphysis have a decreased risk of osteonecrosis when treated with pinning in situ. Complete or partial reduction of an unstable slipped capital femoral epiphysis increases the risk of development of osteonecrosis. Pinning in situ without reduction with a single cannulated screw is the method of choice for the treatment of a slipped capital femoral epiphysis.     

Three cases of slipped capital femoral epiphysis in one family

Slipped capital femoral epiphysis is a relatively common disorder of the hip that affects children in late childhood and early adolescence, with an incidence in the United States of approximately 10 per 100,000. Although the diagnosis and treatment of slipped capital femoral epiphysis have been well described, the search for its cause and a method of early identification continues. Recent publications have suggested that there is a familial association among individuals with slipped capital femoral epiphysis, but there is no current genetic marker established for the disorder. This article reports a series of 3 biologically related Caucasian sisters who were athletic; had body mass indices <26 kg/m(2); had no record of any hormonal imbalances or endocrine abnormalities; had good nutrition; and presented with atypical characteristics of slipped capital femoral epiphysis. This is the first report of a series of 3 sisters with slipped capital femoral epiphysis in the United States. Our goals were to document our experience in the identification and treatment of these patients to highlight the complexities of slipped capital femoral epiphysis presentation patterning, to increase the awareness and reporting of familial cases of slipped capital femoral epiphysis by other physicians, and to encourage additional research in this area. As clinicians progress in the ability to diagnose and treat patients with slipped capital femoral epiphysis, they also must be mindful of the varying presentation characteristics.     

In situ fixation for slipped capital femoral epiphysis: perspectives in 2011

Slipped capital femoral epiphysis is usually treated with in situ fixation to prevent progression of deformity. However, slipped capital femoral epiphysis always is associated with structural risk factors for hip dysfunction in addition to the risk of slip progression. Femoro-acetabular impingement causes some mechanical abnormality in every hip affected by slipped capital femoral epiphysis, even when the slip is mild. The severity of femoro-acetabular impingement caused by slipped capital femoral epiphysis depends on several factors. Cumulative injury to the articular cartilage can result from impingement, and it is better to prevent this type of injury than to treat it later. In situ fixation alone rarely relieves femoro-acetabular impingement in slipped capital femoral epiphysis. Skillful and precise in situ fixation allows careful analysis of hip function in the stabilized slip by eliminating the major risk of acute instability. The more subtle risk of long-term articular damage caused by femoro-acetabular impingement must be considered. The treatment of femoro-acetabular impingement in patients who have slipped capital femoral epiphysis is a separate issue from instability of the proximal femoral physis. Femoro-acetabular impingement must be assessed in every hip that is affected by slipped capital femoral epiphysis, even when the deformity is mild. Several treatment options exist for treating femoro-acetabular impingement associated with slipped capital femoral epiphysis.     

Slipped capital femoral epiphysis: still an emergency

Two case histories are presented in which acute progression of slipped capital femoral epiphysis occurred after a radiographic diagnosis of chronic slipped capital femoral epiphysis had been made. The importance of recognizing the potential for acute progression of a slipped epiphysis and the need for prompt orthopedic intervention are emphasized.     

Fractures of the head and neck of the femur in children: an outcome study

Fractures of the head and neck of the femur in children are very rare, occurring only after a high-velocity trauma, e.g. a fall from a height. This analysis shows the clinical course of traumatic femoral head and neck fractures in paediatric patients. Predisposing factors for poor outcome or fracture complications, such as non-union or femoral head necrosis, are described. Between 1993 and 2006, 16 paediatric patients with proximal femoral fractures were treated at the Level One Trauma Centre of the Medical University of Vienna. The minimum follow-up was two years. Inclusion criteria were age less then 16 years, intact growth plate and a proximal femoral fracture according to the classification by Delbet and Colonna. Exclusion criteria were pathological fractures or fractures of the subtrochanteric region (6/16). Ten patients met the inclusion criteria. Two patients were lost to follow-up. Therefore eight patients were included in the study. All patients except one were operated upon within 48 h after the injury (“primary”) and healed without further complications. A single case was managed by “secondary” surgical treatment, two weeks after the initial trauma resulting in femoral head necrosis that healed without any subjective complaints. This case series confirms the importance of early surgical fixation of proximal femoral fractures in paediatric patients. An operative intervention later then 48 h after the initial trauma may increase the risk of complications such as femoral head necrosis, particularly in Delbet type I fractures (traumatic slipped capital femoral epiphysis).     

Slipped capital femoral epiphysis following ipsilateral femoral fracture.

Two cases of femoral fracture with a subsequent complication of ipsilateral slipped capital femoral epiphysis point out the possible deleterious effects of angular deformity of the proximal femur during the adolescent growth spurt.     

Slipped capital femoral epiphysis with severe vitamin D deficiency

Slipped capital femoral epiphysis is a relatively common disorder in late childhood and early adolescence, with an incidence in the United States of approximately 10 per 100,000. Although clinicians have theorized that contributing factors to the development of slipped capital femoral epiphysis include 25-hydroxyvitamin D deficiency and other nutritional deficiencies, the roles of these factors have not been fully analyzed. This article presents a case of a morbidly obese 13-year-old African-American boy who presented with sudden worsening of chronic hip pain and was diagnosed with stable, bilateral, grade-III slipped capital femoral epiphysis and severe vitamin D deficiency. He was initially treated with bilateral single-screw percutaneous fixation, however, after continued pain and nonunion, a right valgus subtrochanteric osteotomy was performed in association with correction of his severe vitamin D deficiency. This procedure led to improvement of his hip function and successful resolution of the pain. Approximately 3 months after the second operation and vitamin supplementation, the patient had signs of union, and his weight bearing progressed without discomfort. Although the osteotomy provided substantial biomechanical advantage by changing the forces across the physis from shear to compressive, correction of the vitamin D deficiency was critical in providing metabolic capacity for bone healing. Vitamin D plays an important role in bone formation and development, but the level of 25-hydroxyvitamin D is not routinely measured during assessment and treatment of slipped capital femoral epiphysis patients. The early detection and proper treatment of vitamin D may assist in the treatment of patients with slipped capital femoral epiphysis.     

Fractures of the calcaneal apophysis

Eleven patients with 12 open or closed fractures of the calcaneal apophysis were reviewed. The patterns of fracture varied, although all could be classified by a scheme similar to that used for physeal injuries in the long bones. Open injuries involved young children and were associated with subsequent maldevelopment of the posterior (nonarticular) portion of the calcaneus due to growth mechanism damage. The other susceptible age group, adolescence, had two patients with slipped calcaneal apophysis (type 1 injury), similar to slipped capital femoral epiphysis, and three patients with a splitting fracture through the apophysis and physis into the main part of the calcaneus (type 4 injury). Microscopic physeal injury was also observed in the calcaneus of a fatally injured boy.     

Subtrochanteric fracture as a complication of proximal femoral pinning

The circumstances of subtrochanteric fractures following the use of multiple pins for fixation of femoral neck fractures were reviewed in four women (age range, 67-94 years). Internal fixation by use of multiple pins in the proximal femur is a common orthopedic procedure. The pins, however, create a significant stress riser in the lateral subtrochanteric cortex. Subtrochanteric fracture has been reported after internal fixation of slipped capital femoral epiphysis with multiple conventional pins and, recently, after internal fixation of femoral neck fractures with large Garden screws.     

Apophyseal avulsion fracture of the greater trochanter after slipped capital femoral epiphysis: a case report

A 13-year-old boy sustained an avulsion fracture of the left greater trochanter eight months after surgical stabilisation of a slipped capital femoral epiphysis on the same side. In this specific case, avulsion of the greater trochanter after slipping of the capital femoral epiphysis may have been facilitated by weakening of the trochanteric physis.     

Radiological evidence of femoroacetabular impingement in mild slipped capital femoral epiphysis: a mean follow-up of 14.4 years after pinning in situ

Conventional treatment of mild slipped capital femoral epiphysis consists of fixation in situ with wires or screws. Recent contributions to the literature suggest that even a mild slip may lead to early damage of the acetabular labrum and adjacent cartilage by abutment of a prominent femoral metaphysis. It has been suggested that the appropriate treatment in mild slipped capital femoral epiphysis should not only prevent further slipping of the epiphysis, but also address potential femoroacetabular impingement by restoring the anatomy of the proximal femur. Between October 1984 and December 1995 we treated 16 patients for unilateral mild slipped capital femoral epiphysis by fixation in situ with Kirschner wires. In this study we have reviewed these patients for clinical and radiological evidence of femoroacetabular impingement. There was little clinical indication of impingement but radiological evaluation assessing the femoral head-neck ratio and measuring the N?tzli alpha angle on the anteroposterior and cross-table radiographs showed significant alterations in the proximal femur. None of the affected hips had a normal head-neck ratio and the mean alpha angle was 86 degrees (55 degrees to 99 degrees ) and 55 degrees (40 degrees to 94 degrees ) on the anteroposterior and lateral cross-table radiographs, respectively. While our clinical data favours conventional treatment, our radiological findings are in support of restoring the anatomy of the proximal femur to avoid or delay the development of femoroacetabular impingement following mild slipped capital femoral epiphysis.     

Short stature as a screening test for endocrinopathy in slipped capital femoral epiphysis

Slipped capital femoral epiphysis may be associated with hypothyroidism and other endocrinopathies. Routine screening for such abnormalities is unlikely to be cost-effective since the overall incidence of these disorders, in association with slipped capital femoral epiphysis, is low. The identification of a presenting characteristic which would predict the chance of an associated endocrinopathy would allow only selected children to be screened. Our aim was to determine if certain characteristics were useful as a screen for patients with an underlying endocrinopathy who presented with slipped capital femoral epiphysis. Between January 1988 and December 1996 we recorded gender, age, height, unilateral or bilateral involvement and an associated diagnosis of endocrinopathy for all patients who were treated for slipped capital femoral epiphysis. Of 166 such patients 13 (7.8%) had an endocrinopathy. Height was the only useful screening characteristic, although bilateral involvement was more likely in those with an endocrinopathy. Most (90.9%) of this latter group were below the tenth percentile for height compared with only 5.4% in those who did not have an endocrinopathy (p < 0.005). The sensitivity and negative predictive value of detecting an underlying endocrinopathy in a patient presenting with a slipped capital femoral epiphysis and short stature (tenth percentile or less) were 90.2% and 98.6%, respectively. Patients who are on or below the tenth percentile for height at the time of presentation should be screened for a possible endocrine abnormality using measurement of thyroid-stimulating hormone and free thyroxine as a preliminary screening test. These hormones are most likely to be abnormal in the presence of endocrine dysfunction.     

Slipped capital femoral epiphysis. A prospective study of fixation with a single screw.

Forty-four children (fifty-eight hips) who had a slipped capital femoral epiphysis were managed by in situ pinning with a single cannulated screw. This method of treatment was first used in our institution in 1983. Thirty-one boys and thirteen girls were followed for an average of three years (range, two to six years). There were eight acute slips and fifty chronic slips. Thirty-four patients were black and ten patients were white. The clinical criteria of Heyman and Herndon and the radiographic parameters cited by Boyer et al. were used to grade the results. Fifty-four hips were rated as either excellent or good. Avascular necrosis developed in one patient who had an acute slipped capital femoral epiphysis, but chondrolysis did not occur in any patient. The complications included a subtrochanteric fracture in one patient and an increase in the degree of slippage of the capital femoral epiphysis in two patients.     

Outcomes of total hip replacement in patients with slipped capital femoral epiphysis

Background

Total hip replacement has been advocated for the treatment of degenerative hip diseases secondary to slipped capital femoral epiphysis; nonetheless, outcomes of this procedure have not been well established. We reviewed the outcomes of modern total hip replacements in patients who suffered from slipped capital femoral epiphysis.

Methods

A retrospective study was carried out on 32 total hip replacements performed on 28 patients who suffered from slipped capital femoral epiphysis from August 1994 to January 2007. The average age at the time of surgery was 45?years. Clinical evaluation was performed using the Harris Hip Score, radiographic assessment measuring cup and stem orientation, the extent of osteolysis around the implant, and leg length discrepancy. The average follow-up was 98?months (range 25–204?months).

Results

Two total hip replacements failed, one for stem aseptic loosening and the other for modular neck failure. The cumulative survival rate at 9?years was 92.8?%. If the end point was revision for implant loosening, the survival rate improved to 96.8?% at 9?years. The only complication recorded was an intraoperative fracture of the lesser trochanter immediately treated with cerclage wire. At the latest follow-up, the Harris Hip Score averaged 86 (range 70–97). Leg length discrepancies greater than 1?cm were present in 18 cases before surgery, and in only 6 cases after surgery.

Discussion

We recommend total hip replacement for patients who suffer from slipped capital femoral epiphysis because of the satisfactory survival, low complication rate, and the possibility of restoring leg length.     

The value of scintigraphy in hips with slipped capital femoral epiphysis and the value of radiography and MRI after 10 years

Preoperative bone scintigraphy of the femoral head in 33 hips with slipped capital femoral epiphysis, showed no relation to duration of symptoms or degree of slip. The preoperative uptake was always normal or increased. Two hips had postoperative femoral head uptake below normal, both had complications affecting the vascular supply, resulting in necrosis of the femoral head and severe arthrosis. At follow-up after 10 (5-15) years of 28 hips, no relation could be demonstrated between Adolescent Hip Questionnaire which included clinical data, and radiography or magnetic resonance imaging. We only recommend scintigraphy after complications jeopardizing the vascular supply of the femoral head in slipped capital femoral epiphysis.     

Radiological evaluation of unstable (acute) slipped capital femoral epiphysis treated by pinning with Kirschner wires

Treatment of slipped capital femoral epiphysis is still controversial with regard to the implants used for stabilization and the need for prophylactic treatment of the contralateral, unaffected, side. The objective of this study was to ascertain whether prophylactic transfixation of the epiphysis with Kirschner wires in patients with unstable slipped capital femoral epiphysis resulted in significant disturbance of the growth plate and impairment of further growth of the femoral neck and head. Between 1990 and 1999, 29 patients with unstable slipped capital femoral epiphysis were simultaneously treated with internal fixation of the epiphysis and metaphysis with 3-4 Kirschner wires on the affected and the not (yet) affected side. After a mean follow-up of 3.5 years, we evaluated the hip joints radiologically, analysing different roentgenological parameters (CCD angle, femoral head diameter, length of the femoral neck and sphericity of the femoral head). CCD angle, femoral head diameter and length of the femoral neck showed statistically significant (P<0.001, Student's t-test) differences between the affected and unaffected, but prophylactically pinned, sides. Asphericity of the femoral head was found in six cases only on the affected side, whereas all hips, which were operated prophylactically, showed spherical femoral heads at follow-up (P<0.02, Pearson's chi test). These results indicate that the slip itself may cause impairment of the femoral growth plate in patients with unstable slipped capital femoral epiphysis and not stabilization with Kirschner wires. Compared with other series from the literature using different implants (screws, nails), prophylactic transfixation of the epiphysis and metaphysis with Kirschner wires is less compromising to the growth plate on the not (yet) affected side.     

Stress fractures of the femoral neck in child with open capital femoral epiphysis

Stress fracture of the femoral neck has been considered a typical injury of two age groups: active youths and elderly people with osteoporosis. Its occurrence in children with an open capital femoral epiphysis is rare, and only 11 cases have been reported. Here we report two cases, in a 12-year-old boy and a 5-year-old girl (among the youngest patients on record). This fracture can be classified as a compression fracture or a tension fracture. Although tension fractures are not uncommon in military recruits and young athletes, all 13 cases (including our two cases) of femoral neck stress fracture associated with an open capital epiphysis were compression fractures that were treated conservatively.     

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.     

Chondrolysis following slipped capital femoral epiphysis

Medical records and radiographs of 17 known cases of slipped capital femoral epiphysis, treated with in-situ pin fixation and complicated by chondrolysis were reviewed. Fourteen of these 17 hips that developed chondrolysis had definite evidence of pin penetration of the femoral head. One hip had intra-articular pin penetration of the femoral neck. In the remaining two hips, the pins were placed within the anterolateral quadrant of the femoral head and within 2 mm of the articular surface. Overall, this is an 88% incidence of definite intra-articular pin penetration on postoperative radiographs, and a 100% rate if the two probable cases are included. This suggests a correlation between pin penetration and the development of chondrolysis following slipped capital femoral epiphysis.