The correlation between Salter's criteria for avascular necrosis of the femoral head and Kalamchi's prognostic classification following the treatment of developmental dysplasia of the hip.

AIMS: The aim of this study was to evaluate the correlation between Salter's criteria and Kalamchi's classification of avascular necrosis in patients treated for developmental dysphasia of the hip (DDH). PATIENTS AND METHODS: The study involved a retrospective analysis of 123 patients (123 hips) with DDH treated by operative and non-operative reduction before the age of two years, with a minimum follow-up of ten years. Salter's criteria (S1 to S4) were determined from radiographs obtained at one to two years post-reduction, whilst the Kalamchi grade was determined from radiographs obtained at ten or more years of age. Early post-reduction radiographs were also used to evaluate the centre-head distance discrepancy (CHDD) and the occurrence of a dome-shaped deformity of the proximal femoral metaphysis (D-shaped metaphysis). The prognosis was described as good (Kalamchi grade K0 or KI), fair (Kalamchi grade KII) or poor (Kalamchi grade KIII or KIV) for analysis and correlation with the early Salter criteria, CHDD and D-shaped metaphysis. RESULTS: S1 and S2 criteria were predictive of a poor prognosis. The outcome following S3, S4 and S3 + S4 varied; 18 (40%) had a good prognosis, 17 (38%) a fair prognosis and ten (22%) a poor prognosis. A CHDD ≥ 10% and a D-shaped metaphysis were also predictive of a poor prognosis. CONCLUSION: The Salter criteria were predictive of the Kalamchi grade of avascular necrosis in patients with DDH aged ten or more years after reduction of the hip. Cite this article: Bone Joint J 2017;99-B:1115-20.

Treatment for developmental dysplasia of the hip using the Pavlik harness: long-term results.

We reviewed the medical records of 115 patients with 130 hips with developmental dysplasia with complete dislocation in the absence of a neuromuscular disorder, spontaneous reduction with a Pavlik harness, and a minimum of 14 years' follow-up. The mean age at the time of harness application was 4.8 months (1 to 12) and the mean time spent in the harness was 6.1 months (3 to 12). A total of 108 hips (83.1%) were treated with the harness alone and supplementary surgery for residual acetabular dysplasia, as defined by an acetabular index > 30 degrees , was performed in 22 hips (16.9%). An overall satisfactory outcome (Severin grade I or II) was achieved in 119 hips (91.5%) at a mean follow-up of 16 years (14 to 32) with a follow-up rate of 75%. Avascular necrosis of the femoral head was noted in 16 hips (12.3%), seven of which (44%) underwent supplementary surgery and nine (56%) of which were classified as satisfactory. The acetabular index was the most reliable predictor of residual acetabular dysplasia.

A proposed prognostic formula for Perthes' disease.

UNLABELLED: We retrospectively reviewed 145 patients with unilateral Perthes' disease and compared a quantitative analysis of early radiographic signs with a predicted prognosis at long-term followup. The average age of the patients at followup was 18.7 years (range, 16.2-27.5 years). We used the age at onset and three radiographic factors as independent variables for multiple regression analysis. The final radiographic results were based on a modified Stulberg's classification as the dependent variable. Fifty patients (35%) had a good outcome, 33 patients (23%) had a fair outcome, and 62 patients (42%) had a poor outcome. The most reliable formula in the stepwise multiple regression analysis was calculated as: y = -0.697 + 0.418 (age score) + 0.860 (involvement score) + 0.248 (subluxation score). The radiographic stage at first visit had no influence on the final results. Multifactorial assessment by combination of age at onset and two radiographic factors (epiphyseal involvement and subluxation) was the most reliable for predicting the prognosis. A score of 1.5 points or less predicted a good prognosis and a score of 2.6 or more indicated a poor prognosis. LEVEL OF EVIDENCE: Prognostic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

A paired study of Perthes' disease comparing conservative and surgical treatment.

We performed a paired study of mature patients with Perthes' disease to compare the radiological results after treatment between conservatively- and surgically-treated groups. One patient was selected from each group to create the pairs for this study. Each pair was strictly matched for gender, body mass index, age at onset, stage at the first visit, necrotic area and radiological at-risk signs and each was assessed by comparing the values of six radiological measurements. Eighteen pairs (36 hips) fitted the criteria. The radiological measurements which showed a statistically better result in the surgical groups were Mose's method, the acetabular-head index and leg-length discrepancy. There were no statistical differences in the slope of the acetabular roof and the articulotrochanteric distance. Four hips in the conservative group were in Stulberg class II, five in class III and nine in class IV. In the surgical group, 13 were in Stulberg class II, four in class III and one in class IV. We conclude that surgical treatment improved the sphericity of the femoral head and provided greater acetabular cover, but did not reform the acetabular roof. It was noteworthy that a greater leg-length discrepancy and a smaller articulotrochanteric distance were not seen in the surgical group. Our study suggests that surgical treatment is preferable in patients with severe Perthes' disease.

Natural history of infantile tibia vara.

We have observed the natural history without treatment of 46 limbs in 29 patients with infantile tibia vara and a metaphyseal-diaphyseal angle (MDA) of more than 11 degrees. The femorotibial angle (FTA) and MDA were measured, and Langenskiöld's classification of radiological changes in the proximal medial metaphysis of the tibia was used. In 22 limbs which were not in Langenskiöld stages II to III the condition resolved spontaneously without treatment. Of the remaining 24 which were in stages II to III, in 18 it resolved spontaneously by the age of six years, but six showed little or no improvement at the latest follow-up. It was impossible to differentiate by measuring the FTA or MDA whether spontaneous resolution could be expected before the age of four years. There was no difference in the rate of resolution of the deformity between those patients who had been treated by a brace and those who had received no treatment. We advise no initial treatment but review at six-monthly intervals until the age of four years, even in patients with Langenskiöld stage-II to stage-III deformity. When a deformity persisted or progressed we carried out a corrective osteotomy after the age of four years.

MRI study of talonavicular alignment in club foot.

We studied in vivo the talonavicular alignment of club foot in infants using MRI. We examined 26 patients (36 feet) with congenital club foot. The mean age at examination was 9.0 months (4 to 12). All analyses used MRI of the earliest cartilaginous development of the tarsal bones in the transverse plane, rather than the ossific nucleus. The difference in the mean talar neck angle (44.0 +/- 8.1 degrees) in club foot was statistically significant (p < 0.001) when compared with that of the normal foot (30.8 +/- 5.5 degrees). The difference between the mean angles in the group treated by operation (47.9 +/- 6.7 degrees) and those treated conservatively (40.1 +/- 7.5 degrees) was also statistically significant. The anatomical relationship between the head of the talus and the navicular was divided into two patterns, based on the position of the mid-point of the navicular related to the long axis of the head. In the operative group, 18 feet were classified as having a medial shift of the navicular and none had a lateral shift. In the conservative group, 12 showed a medial shift of the navicular and six a lateral shift. All nine unaffected normal feet in which satisfactory MRI measurements were made showed a lateral shift of the navicular. Club feet had a larger talar neck angle and a more medially deviated navicular when compared with normal feet. This was more marked in the surgical group than in the conservative group.

Evaluation of pathologic abnormalities of clubfoot by magnetic resonance imaging.

Three-dimensional analyses of clubfoot in infants younger than 1 year of age were done using magnetic resonance imaging in an in vivo study. Twenty-one patients (31 feet) with congenital clubfoot were examined. The average age at examination was 8.6 months (range, 4-12 months). All patients originally were treated using corrective casts. Seventeen feet required complete subtalar release operations and the remaining 14 feet were treated conservatively with various orthoses. Four measurements using magnetic resonance imaging were performed in the transverse and coronal planes as follows: the calcaneus adduction angle, to define the degree of medial rotation of the calcaneus in the transverse plane; the navicular angle, to define the degree of medial displacement of the navicular; the talus neck angle, to define the degree of medial angulation of the talus; and the calcaneus shift index, to define the degree of medial shift of the calcaneus beneath the talar head in the coronal plane. In the results, all four measurements of clubfoot on magnetic resonance imaging were statistically different from those of normal feet. In the surgical group there were statistical differences in the calcaneus adduction angle, the navicular angle, and the calcaneus shift index (including two feet of patients whose parents had rejected proposed treatment), compared with the conservative group, but there was no statistical difference in the talus neck angle. Magnetic resonance imaging could delineate the three-dimensional abnormalities of the tarsal bones in clubfoot and quantitatively evaluate the severity of clubfoot.

Domain-specific mutations in TGFB1 result in Camurati-Engelmann disease.

Camurati-Engelmann disease (CED, MIM 131300) is an autosomal dominant, progressive diaphyseal dysplasia characterized by hyperosteosis and sclerosis of the diaphyses of long bones. We recently assigned the CED locus to an interval between D19S422 and D19S606 at chromosome 19q13.1-q13.3, which two other groups confirmed. As the human transforming growth factor-1 gene (TGFB1) is located within this interval, we considered it a candidate gene for CED.

Assessment of stability in children's minimally displaced lateral humeral condyle fracture by magnetic resonance imaging.

We studied 12 children who had minimally displaced lateral humeral condyle fractures. Bony gaps at the fracture site were <2 mm on the anteroposterior view of plain radiographs. To determine the stability of the fractures, we used a magnetic resonance imaging (MRI) study of the distal humerus and elbow joint. In the results, two types of fractures were classified by the extent of the fracture line in MRI. Type I showed that the line coursed from the lateral metaphysis to the growth plate but not through it. In type II, the line crossed the growth plate to enter the joint space. We concluded that the MRI study distinguished the potentially unstable fracture (type II) from the minimally displaced fracture and recommend the use of a percutaneous pin fixation for the expected unstable fracture.

Ludloff's medial approach for open reduction of congenital dislocation of the hip. A 20-year follow-up.

We reviewed 33 patients (35 hips) after open reduction of congenital dislocation of the hip using Ludloff's medial approach. The mean age at the time of operation was 14 months (5 to 29) and at the time of final follow-up 20.1 years (15 to 24) giving a mean duration of follow-up of 19.4 years (14 to 23). We evaluated the radiological results by the Severin classification and the extent of avascular necrosis using the criteria of Kalamchi. At the latest review 16 hips (45.7%) were in Severin groups I or II (acceptable results) and 19 (54.3%) in Severin groups III, IV or V (unacceptable results). There was evidence of avascular necrosis in 15 hips (42.9%). The radiological results began to become worse at about the age of ten years when type-II avascular changes presented. We conclude that Ludloff's medial approach for open reduction is unsatisfactory for the treatment of congenital dislocation since about half of our patients required additional operations.

Limb lengthening and correction of angulation deformity: immediate correction by using a unilateral fixator.

We performed limb lengthening (callus distraction) with immediate correction of the angulation deformity in 11 patients (16 long-bone segments) in Chiba Children's Hospital. The operated segments were 14 tibias and two femurs. The average age at operation was 12.0 years (range, 4.8-15.3). All had varus deformities and limb shortening. We used the Orthofix unilateral fixator in all cases. The following two types of osteotomy were selected, depending on the degree of the varus deformity: opening wedge osteotomy if it was < 20 degrees or dome osteotomy if > 20 degrees. The average amounts of the leg lengthening and the correction angle were 32.4 mm (range, 20-50) and 23.8 degrees (range, 15-40 degrees). The average of the healing index was 32.6 days/cm (range, 28.5-36.8 days/cm). There was also no difference in healing index between the two osteotomies groups, despite the greater angular correction in the dome osteotomy group. We concluded that our method of lengthening with immediate correction of deformity was a very simple and effective method.

The use of a hydroxyapatite block for innominate osteotomy.

We used hydroxyapatite blocks to keep open Salter innominate osteotomies in 19 children (21 hips), avoiding the need for an autograft taken from the anterior superior iliac spine. Our results were satisfactory, with less deformation of the iliac bone, and a reduction of both blood loss and operating time.

Acetabular remodelling in Perthes' disease after primary healing.

We conducted a study to assess the remodelling potential of the acetabulum of 29 children with Perthes' disease. In all but four, the acetabular head index (AHI) increased in the time between primary healing of the femoral head and follow-up at skeletal maturity. We classified 13 cases (44.8%) in which the increase in AHI was more than 10% as group I. In this group, the outcome at follow-up was predictable when subluxation during the active phase of the disease decreased until primary healing. Our observations suggest that the position of the femoral head, rather than sphericity, is the most important factor in acetabular growth and remodelling.

Spinal dysraphism. A study of patients over the age of 10 years.

Thirty patients over the age of 10 years, exhibiting cutaneous manifestations on the back suspected to be due to spinal dysraphism, and neurologic deficits, were studied to analyze neurologic appearance. Neurologic deficits appeared by age 5 in 26 patients. No patient complained of low-back pain or sciatica. Paralytic deformities of the lower extremities were divided into four grades for evaluation: A = no deformity, with only urinary disturbance (four cases); B = toe-limited deformity (two cases); C = toe and foot-limited deformity (six cases); D = toe, foot, ankle, and lower limb deformity (18 cases). Patients with slight neurologic disturbance, either Grade A or without urinary disturbance, were seen among the patients who had undergone a release operation by age 2, although neurologic appearance in patients in severe grades was not related to the age at release operation. Also, the release operation was thought to be effective in preventing low-back pain or sciatica.

Acetabular cover in congenital dislocation of the hip.

The exact measurement of femoral head cover is essential for an assessment of reduction of congenital dislocation of the hip. We have compared standard anteroposterior radiographs with computerised tomograms and thereby classified the shape of the acetabular roof into four types. We found that the CE angle of Wiberg is a more reliable measure of head cover when the lateral point of bony condensation of the roof is chosen as the reference point rather than the edge of the bone, where these two points do not overlap. We conclude that head cover can be more accurately determined in younger children with dysplastic hips by our 'refined' CE angle, than by the original method of Wiberg.

Experimental avascular necrosis of the femoral capital epiphysis and induced subluxation of the hip in young rabbits.

We attempted to clarify experimentally the effect of hip joint incongruity on the necrotic femoral head. Twenty-four immature rabbits were divided into three groups: group I (12 rabbits), interruption of the epiphyseal artery and immobilization of the knee in extension for inducing subluxation of the hip; group II (six rabbits), interruption of the epiphyseal artery; group III (six rabbits), opening of the capsule (with preservation of the epiphyseal artery) and immobilization of the knee in extension. Radiographic examination of the hips of the rabbits in group I showed severe deformation of the necrotic femoral head with subluxation. These radiographic findings appeared similar to those of human hip joints affected with Perthes' disease.

Arthrography of early Perthes' disease. Swelling of the ligamentum teres as a cause of subluxation.

Hip arthrography was performed in 19 patients in the initial stage of Perthes' disease. Sphericity and subluxation were measured and it was found that subluxation was independent of the femoral head deformity. We therefore tried to identify the cause of early subluxation: in seven patients a swollen ligamentum teres was thought to be responsible, and was associated with medial pooling of the contrast medium. A swollen ligamentum teres was seen in another seven cases; the other five arthrograms were normal. These findings were further clarified by enhanced CT scans, which confirmed that ligament swelling may be an important cause of early subluxation.

Comparative study of Perthes' disease treated by various ambulatory orthoses.

Ninety-six hips of 90 patients treated by three different orthoses, Thomas type, Tachdjian type and Atlanta type, were radiologically and clinically surveyed to evaluate the containment effect and the influence of weight-bearing. The Tachdjian and Atlanta types which introduced the containment method yielded good or fair results in 69% and 77% of cases respectively--clearly higher than the 52% with the Thomas type which only relieved weight-bearing. Comparison of the results between the Tachdjian type with non weight-bearing and the Atlanta type with weight-bearing, no significant difference was found but the latter had some advantages in terms of improved hip abduction, ease of movement and fit. Therefore, we are encouraged to continue the use of the Atlanta type for ambulatory orthotic treatment of the Perthes' disease. However, the rate of poor results could be expected in about 20% to 30% even in the Atlanta type. Another type of treatments should be chosen for the patient in whom the poor result is anticipated with our protocol.