Hip arthrodesis using the AO modular external fixator

Arthrodesis remains the treatment of choice for children and young adults with deteriorated, painful hip joints. In 1992, Fernandez Dell'Oca et al. reported on the use of the AO external fixator in hip arthrodesis. Three patients who underwent this procedure are reported. Hip arthrodesis with AO modular external fixator has all the benefits of the Thompson arthrodesis, with the added advantages of producing a solid fusion in the correct position and allowing the patient to remain ambulatory while using the external fixator.

Bone disease in African children with slipped capital femoral epiphysis: histomorphometry of iliac crest biopsies

African teenagers with slipped capital femoral epiphysis (SCFE) not infrequently also have genu valgum (knock-knee). Because we had previously demonstrated metabolic bone disease attributable to dietary calcium deficiency in black teenagers with genu valgum, we examined 29 black teenagers (15 male, 14 female) with SCFE for metabolic bone disease. Each patient had an iliac crest bone biopsy taken (after double tetracycline labeling) for routine histomorphometry, and blood and urine samples for bone biochemistry. Spinal bone mineral density was measured in 13 patients. Compared to reported data, we found our patients to be sexually more immature, older, at least as obese, and to have more severe and more frequently bilateral hip disease. Eighty percent of the children took dairy products only once or twice a week or less frequently, and 37.9% had genu valgum. Compared with race- and age-matched South Africans, bone biopsies in our patients showed lower bone volume (BV/TV, p = 0.0003), wall thickness (p = 0.0002), and trabecular thickness (Tb.Th, p = 0.0002), and a tendency to greater trabecular spacing (Tb.Sp, p = 0.053). Lower osteoid volume (OV/BV, p = 0.0001), osteoid surface (OS/BS, p = 0.0001), osteoid thickness (O.Th, p = 0.0002), double labeled surface (dLS/BS, p = 0.029), and bone formation rate (BFR/BS, p = 0.037) suggested poorer bone forming capacity in our patients. No evidence of hyperparathyroid bone disease or osteomalacia was found. BV/TV was below the reference range (14.2%) in 65.5% of cases; these patients had lower values for Tb.Th (p = 0.037) and Tb.N (p = 0.0003), greater Tb.Sp (p = 0.0002), a tendency to lower adjusted apposition rate (Aj.AR, p = 0.057), and had had less frequent intake of dairy products than those with normal BV/TV (p = 0.024). Furthermore, months since menarche correlated with histomorphometric variables BV/TV (r = 0.667, p = 0.009), Tb.Th (r = 0.745, p = 0.002), Tb.Sp (r = -0.549, p = 0.042), O.Th (r = 0.784, p = 0.0009), and Aj.AR (r = 0.549, p = 0.042). The correlation between Tb.Th and spinal bone mineral content (r = 0.656, p = 0.015) suggests that the reduced trabecular thickness reflected a generalized bone condition. A greater than normal proportion of patients had spinal bone mineral density values below -1 standard deviation (SD) of the mean (osteopenia) (p = 0.001). Patients tested for parathyroid hormone and 25-hydroxyvitamin D levels were found to have normal values. Parathyroid hormone correlated with Aj.AR (r = 0.661, p = 0.038) and serum phosphorus (r = -0.764, p = 0.010). We conclude that sexual immaturity and possibly past dietary calcium deficiency contributed to osteopenia, and that this, together with obesity, led to the development of more severe and more frequently bilateral SCFE in our patients than in reported series of black and white children.

Long-term results after nailing in situ of slipped upper femoral epiphysis. A 30-year follow-up of 59 hips

We reviewed the radiological and clinical long-term results after the nailing in situ of slipped upper femoral epiphysis in 59 hips in 43 patients. The displacement of the epiphysis had been measured as the 'slipping angle' before operation and related to the results at follow-up at a mean of 30.9 years (27 to 34). The mean age at follow-up was 44.2 years (39 to 50). Radiographic re-examination of 41 hips with slipping angles of < or =30 degrees at the time of operation showed that eight (20%) had developed mild osteoarthritis and one had severe changes. For 18 hips with slipping angles ranging from 31 to 50 degrees at surgery six (33%) had mild osteoarthritis and three had severe changes. The differences did not quite achieve statistical significance (p = 0.09). Clinical re-examination of the 41 hips with slipping angles of < or =30 degrees showed fair or poor results (Harris hip score <90) in three (7%). In the 18 hips with slipping of 31 to 50 degrees, four had fair or poor results (22%) (p = 0.13). We conclude that nailing in situ for slipping of < or =30 degrees, using one thin nail, can give excellent long-term results. At present we recommend that hips with slips ranging from 31 to 50 degrees should also be nailed in situ, but further long-term studies are required, especially on the choice between nailing in situ and corrective osteotomy for slips in excess of 50 degrees.

Subclinical slipped capital femoral epiphysis. Relationship to osteoarthrosis of the hip

We examined the femora of 2665 adult human skeletons from an osteological collection to determine the prevalence of post-slip morphology termed femoral head-tilt deformity by Murray and pistol-grip deformity by Stulberg et al. The hypothesis was that primary osteoarthrosis of the hip is a secondary manifestation of a subclinical developmental disorder of the hip. The prevalence of post-slip morphology was 8 per cent (215 of 2665 skeletons). Severe osteoarthrosis was more prevalent in association with post-slip morphology (116 [38 per cent] of 306 hips) than in the matched controls (seventy-nine [26 per cent] of 306 hips) (p < 0.005). In the skeletons that had unilateral post-slip morphology, severe osteoarthrosis was more prevalent in the involved hips (thirty-one [37 per cent] of eighty-three) than in the contralateral, normal hips (eighteen [22 per cent] of eighty-three) (p < 0.05). Post-slip morphology, which was unrelated to age, was found to be a major risk factor for the development of high-grade osteoarthrosis. We noted evidence of high-grade osteoarthrosis in sixty-three (68 percent) of the ninety-three hips with minimum post-slip morphology in skeletons from individuals who had been fifty-six years old or more at the time of death compared with forty-five (48 percent) of the ninety-three control hips. This difference was significant (p < 0.025) [corrected]. The osteoarthrosis in the hips with post-slip morphology was distinctly characterized by anterior flattening of the acetabulum, cystic degeneration in the anterior metaphyseal-epiphyseal region, and progression to global osteoarthrosis of the hip.

Acute slipped capital femoral epiphysis: the value and safety of urgent manipulative reduction

A 40-year experience consisting of 91 cases of acute slipped capital femoral epiphysis (SCFE) was reviewed to assess the safety of manipulative reduction and to determine whether urgent reduction has an effect on the development of avascular necrosis (AVN) of the capital femoral epiphysis. All patients had a history of sudden onset of severe hip pain and were documented to have an unstable (acute) slipped epiphysis. Treatment modalities included manipulative reduction under general anesthesia followed by internal fixation (41 hips), epiphysiodesis and internal fixation (15 hips), epiphysiodesis and cast immobilization (31 hips), and cast immobilization alone (three hips). One case was treated with cast immobilization after reduction by skeletal traction. Patient follow-up averaged 44 months, and ranged from 12 to 216 months. Radiographic review identified 13 (14%) cases of AVN in the series of 91 hips. Of 42 hips reduced in <24 h from presentation, AVN developed in three (7%). Of 49 hips reduced in >24 h from presentation, AVN developed in 10 (20%). Manipulative reduction of the acute SCFE may be accomplished without increased risk of AVN. Time to reduction may be an important risk factor for development of AVN after acute SCFE.

Slipped capital femoral epiphyses in a patient with primary hyperparathyroidism

Slipped capital femoral epiphyses are rarely associated with primary hyperparathyroidism, and only four cases have been documented in the English literature. We report such a case. A 13-year-old boy presented with bilateral slipped capital femoral epiphyses. Investigation showed that he had primary hyperparathyroidism due to a parathyroid adenoma. The adenoma was removed, and then the epiphyses were pinned in situ 3 weeks later. The pins were removed 3 months postoperatively when the physes had closed. The patient had a painless hip 1 year later at follow-up. We concluded that identification and excision of the hyperparathyroid adenoma and in situ pinning of the slipped epiphyses results in satisfactory treatment of the condition.

Slipped capital femoral epiphysis

SCFE is the most common hip abnormality in adolescence. The subsequent development and severity of degenerative changes is related to the degree of slippage and to delay in diagnosis. Awareness of this diagnostic possibility in the population at greatest risk and knowledge of subtle and early radiographic findings will allow prompt diagnosis and treatment of SCFE. Follow-up radiographic examination should be used to evaluate for physeal fusion and any complications, including progression of the slip, hardware complications, chondrolysis, avascular necrosis, and secondary osteoarthritis.

Slipped capital femoral epiphysis associated with renal failure osteodystrophy

A retrospective institutional and literature review of 31 children (20 boys and 11 girls) with 58 renal failure-associated slipped capital femoral epiphyses (RFASCFEs) was performed. The average age at diagnosis of renal failure was 8.9 years, and for RFASCFE 11.5 years, with a linear correlation between these two ages. All patients had secondary hyperparathyroidism at diagnosis of the RFASCFE. The median height and weight were below the 5th percentile. The RFASCFEs were stable and bilateral in 95% of the children. Slip magnitude was mild in 53%, moderate in 8%, and severe in 39%. Avascular necrosis was associated with steroid immunosuppression in children with renal transplants. All children were treated with medical management; surgery was used in an additional 29 hips. If correction of secondary hyperparathyroidism is not achieved within 2 months, RFASCFEs are likely to progress and surgical stabilization is recommended.

Three common causes of childhood hip pain

Disorders of the hip that result in pain during childhood are not random and chaotic events. The work of numerous investigators demonstrates that each condition has distinguishing characteristics. These characteristics are found in the manner of presentation, the physical examination, and the diagnostic study. Familiarity, with these conditions, attention to the details of the patients' history, and a careful eye for the details of physical examination allow skillful physicians to devise a plan of investigation that results in a successful diagnosis.

Is severe renal osteodystrophy a contraindication for recombinant human growth hormone treatment?

Recent extension of the use of recombinant growth hormone (rhGH) to non-growth hormone-deficient patients necessitates close attention to possible complications in these patients, including effects on bone. Recent studies on the use of rhGH in children with chronic renal failure (CRF) provide some early data. No significant differences in radiographic osteodystrophy scores, serum calcium, phosphorus, or parathyroid hormone (PTH) levels were found between treated and untreated groups. Alkaline phosphatase increased transiently. The effect of renal osteodystrophy on growth response has not yet been reported. Animal models demonstrate that GH stimulates chondrocyte proliferation. Experimental data further suggest that GH can weaken the epiphyseal plate. Slipped capital femoral epiphysis has been reported in GH-deficient patients, before, during, and after GH therapy. In CRF patients treated with GH, slipped capital femoral epiphysis has also been reported. As renal osteodystrophy and hypocalcemia are risk factors for this condition, the relationship to GH therapy is unclear in these patients. Avascular necrosis, known to be associated with slipped capital femoral epiphysis and CRF, has also been reported in patients receiving GH, although the relationship to the therapy is unknown. Children with CRF treated with rhGH should be serially monitored for renal osteodystrophy, slipped capital femoral epiphysis, and avascular necrosis with serial radiographs and serum calcium, phosphorus, alkaline phosphatase, and PTH levels.

Acute slipped capital femoral epiphysis. Review of outcomes and rates of avascular necrosis

One hundred and forty-nine patients (208 hips) were managed for slipped capital femoral epiphysis at the Hospital for Sick Children in Toronto from 1980 through 1990. We retrospectively reviewed the records of twenty-four patients (twenty-six hips) who had an acute slipped capital femoral epiphysis to evaluate the outcome of treatment and possible risk factors for avascular necrosis associated with this condition. The patients were evaluated with the Iowa hip-scoring system, a physical examination, and anteroposterior and lateral radiographs. The severity of degenerative joint disease was assessed on the radiographs with use of the system described by Boyer et al. Eighteen slips were classified as grade 1; seven, as grade 2; and one, as grade 3, according to the system of Southwick. Twenty-three hips were treated with in situ pinning and three, with reduction and pinning. The mean duration of follow-up was 5.9 years (range, 2.1 to 12.8 years). Poor Iowa hip scores and more severe degenerative changes were related to the development of avascular necrosis and to the severity of the slip. Avascular necrosis developed in four hips (15 per cent), two of which had had a reduction. Multiple logistic regression analysis, which included all 150 slips (both acute and chronic) for which there was adequate follow-up, showed that the rate of avascular necrosis was related to both the severity and the acute nature of the slip.

Endocrine disorders and orthopedic problems in children

Endocrine excesses or deficiencies frequently result in alterations of height as compared with age-matched children. Less clinically obvious are significant alterations in bone metabolism leading to osteoporosis, which can affect the child and may affect the patient as an adult. Slipped capital femoral epiphysis appears to be associated with a variety of endocrine disorders, particularly hypothyroidism. The hormonal treatment of various endocrine and nonendocrine disorders has been associated with alterations of bone metabolism, or of bone maturation, as well as with producing or aggravating orthopedic disorders.

Screw fixation of Grade III slipped capital femoral epiphysis

From 1987 to 1992, 161 children were treated at The Children's Hospital of Philadelphia for slipped capital femoral epiphysis. Of these, 23 patients (23 hips) had Grade III slips (> 50%). Fixation was achieved by 1 or 2 screws in all patients. Twenty-one of 23 patients were available for followup (average followup, 2.8 years). Four slips were acute, 11 were acute-on-chronic, and 6 were chronic. At the most recent followup, radiographs were taken and a Harris Hip Score was assigned for each patient. Stabilization without progression of slip at followup was achieved in all patients. Screw placement was satisfactory per the criteria of Stambough in all patients. Four children (19%) had major complications: Three (1 acute slip and 2 acute-on-chronic slips) had avascular necrosis of the femoral head; One (chronic slip) had chondrolysis. There were no immediate postoperative complications. The mean Harris Hip Score for these 4 patients was 85 points, versus a mean score of 94 points for all 21 patients. Chronic Grade III slipped capital femoral epiphysis can be treated safely and effectively by screw fixation. Five of 6 patients had satisfactory results; the only exception had evidence of chondrolysis preoperatively. Acute and acute-on-chronic Grade III slipped capital femoral epiphyses treated with screw fixation are less predictable. In 15 patients, reduction occurred in 9 hips despite deliberate avoidance of forceful manipulative maneuvers. Avascular necrosis developed in 3 (33%) of these 9 hips. Reduction of the acute component of the slip during screw fixation, whether deliberate or not, indicates gross instability. It is hypothesized that avascular necrosis may be associated with injury to the epiphyseal vasculature occurring at the time of the acute slip.

Natural history of untreated chronic slipped capital femoral epiphysis

From 1915 to 1952, 31 hips in 28 patients with slipped capital femoral epiphysis were observed without interventional treatment at the University of Iowa Department of Orthopaedic Surgery. A slip was considered chronic if the symptoms had been present for 3 weeks or more. The severity of the slip was determined by radiographs. Assessment included Iowa Hip Rating and grading of radiographic degenerative changes. The mean duration of patient followup from the onset of symptoms was 41 years. The mean patient age was 54 years old at review, and 13 years old at onset of symptoms. Degenerative arthritis developed in hips with displaced slipped capital femoral epiphysis. Untreated slipped capital femoral epiphysis can progress to a severe degree. The natural history of chronic slipped capital femoral epiphysis is favorable provided that displacement is minimal and remains so.

Treatment of the unstable (acute) slipped capital femoral epiphysis

Slipped capital femoral epiphysis, the most common hip disorder in adolescence, traditionally has been classified according to symptom duration. An acute slip is 1 in which there are symptoms for < 3 weeks; for a chronic slip, there are symptoms for > 3 weeks. An acute-on-chronic slip is characterized by a combination of both with a recent exacerbation of symptoms. This classification system is misleading because it does not consider stability. A stable slipped capital femoral epiphysis has a good prognosis, but an unstable slip has a guarded prognosis. The priorities in treating an unstable (acute) slip are (1) to avoid avascular necrosis, (2) to avoid chondrolysis, (3) to prevent further slip, and (4) to correct deformity. The last priority, correcting the deformity, is associated with a high incidence of complications including avascular necrosis and chondrolysis, so manipulative reduction under anesthesia or an acute corrective osteotomy is not recommended. To address these priorities in treatment, the authors recommend preoperative bed rest to decrease the synovitis and intraarticular effusion. Operative stabilization is done in an elective fashion once the synovitis has subsided. The technique includes careful patient positioning on the fracture table, which may cause an incidental reduction, but no attempt is made to do a manipulative reduction. The technique is dependent on radiographic control. The femoral head and neck must be well visualized on the anteroposterior and lateral intensifier images before the operation is started. The slipped capital femoral epiphysis is stabilized with a single central screw, and nonweightbearing ambulation with crutches is recommended until a satisfactory painless range of motion has returned.

Chondrolysis and avascular necrosis: complications of slipped capital femoral epiphysis

Chondrolysis and avascular necrosis (AVN) are serious complications after slipped capital femoral epiphysis (SCFE). Chondrolysis, or acute cartilage necrosis of the capital femoral epiphysis, can occur in treated and untreated SCFE. Its exact etiology has not been conclusively determined, and there may be some connection with hardware penetration into the joint and its development. Because chondrolysis can occur in both treated and untreated hips, an immune mechanism has been postulated. Although some evidence of immune reaction has been confirmed in the joint, no screening test has yet been developed to determine susceptible individuals. AVN is clearly related to impeded blood supply to the femoral head and to severely slipped unstable acute slips. Forceful reduction of the femoral head must be avoided. However, some slips are so unstable that reductions occur merely with positioning of the patient for operation. Improperly placed fixation devices may also play a role in the development of AVN. Chondrolysis and AVN may not be completely avoidable in the treatment of SCFE.

The contralateral hip in slipped capital femoral epiphysis

The risk of contralateral slipping in slipped capital femoral epiphysis (SCFE) has been estimated to be 40-80% in follow-up examinations. Before age 50 years, 25% of the contralateral hips with untreated slipping showed arthrosis, some severe. In the same long-term follow-up, no hip with mild or moderate slipping treated with pinning in situ had developed severe arthrosis at that age, indicating the risk of arthrosis in the contralateral hip in SCFE can be reduced by prophylactic pinning. Prophylactic pinning also diminishes the need for repeated radiographical examination during the remaining growth period. Provided that a technique with a low complication rate is used, prophylactic pinning of the contralateral hip is recommended in all cases of SCFE.

Slipped capital femoral epiphysis. Incidence and clinical assessment of physeal instability

In an unselected series of 55 cases of slipped capital femoral epiphysis (SCFE) we observed an incidence of 25% of epiphyseal reduction, mostly unintentional. Reduction indicated physeal instability and was associated with an effusion, detected by sonography on admission, and inability to bear weight. The true prevalence of instability may be higher since an effusion was noted in 33 cases (60%) on the initial sonographic assessment. Serial radiographs showed reduction in 12 (22%), with an average change of 15.1 degrees in the head-neck angle. Serial sonography showed reduction in 7 out of 20 cases (35%), with an average change of 3.7 mm in displacement. In two cases reduction was seen on sonography but not on radiography. Of the hips which showed subsequent reduction, 12 had had a bone scan on admission; three showed initial epiphyseal avascularity but only one progressed to symptomatic avascular necrosis. All stable hips had normal epiphyseal vascularity on the initial bone scan. This indicates the importance of injury from the initial displacement in causing avascular necrosis, rather than effusion, vascular compromise or iatrogenic injury from gentle repositioning. Physeal instability in SCFE is common and should be assessed clinically on admission. It is indicated by joint effusion or inability to bear weight. A slip is very unlikely to be unstable in a child able to bear weight and with no sonographic effusion.

[Epiphysiolysis of the femoral head--can surgery prevent later arthritis?]

Slipped capital femoral epiphysis is one of the few orthopaedic emergencies. All orthopaedic surgeons agree that operation is the treatment of choice. In early stages, complete healing is possible. Fixation in situ is sufficient. If there is more severe dislocation of the head of the femur, the results become worse. More sophisticated and more difficult interventions aim at correction of the deformity, which may be a preliminary stage ['prearthrosis'] of osteoarthritis later in life. According to the extent of the slip, the surgeon may choose among different operations. The decision in a particular case is not easy. Complications are relatively frequent and sometimes severe. Long-term control show the late results and can thereby give guidelines for the surgeon's choice. Early diagnosis, however, is still decisive for a good prognosis in later life. As the disease is rather rare, the doctor who sees the patient first must be aware of it. Even at an early stage diagnosis can always be made on the basis of history, clinical findings and two X-rays.

Treatment of slipped capital femoral epiphysis with severe displacement (report of 14 hips in 12 non Caucasian patients)

This paper presents a report of a study of 14 hips in 12 non Caucasian patients treated for severe slipped capital femoral epiphysis. There were four Sudanese, two Syrians, and six Libyan patients. Three hips in two patients had severe acute slip and eleven hips in ten patients had severe chronic slip. Patients with severe acute slip were treated by closed reduction and internal fixation. Patients with severe chronic slip were treated by open replacement of the femoral epiphysis using the procedure advocated by Dunn and Angel[1]. One patient treated for acute severe slip developed over reduction of the epiphysis after closed manipulation. The results were good in all the three hips with acute slip. Two hips with severe chronic slip developed avascular necrosis and chondrolysis. Considering the results in this small series, closed reduction and internal fixation is a satisfactory method of treatment for severe acute slip while results of open replacement of the epiphysis for severe chronic slip has high incidence of complication in non caucasian patients as compared to those reported for caucasians.

The management of severe avascular necrosis following slipped capital femoral epiphysis by transtrochanteric rotational osteotomy. Results of successful treatment in two cases with longterm follow-up

We present two cases of unstable slipped capital femoral epiphysis complicated by avascular necrosis that were successfully treated with transtrochanteric anterior rotational osteotomy. These two cases both had severe avascular necrosis and were felt to be unsalvageable. We recommend this surgical technique as a viable alternative to other forms of treatment in this selected patient population.