Deborah F. Stanitski

Orthopaedic manifestations of Ehlers-Danlos Syndrome

Ehlers-Danlos syndrome is the most prevalent heritable disorder of connective tissue. Musculoskeletal problems include joint pain, swelling and instability, and spinal deformity. This study was undertaken to assess functional orthopaedic problems of patients with Ehlers-Danlos syndrome. Sixty patients with genetically verified Ehlers-Danlos syndrome (range, 8-60 years; mean, 34 years) who attended a National Ehlers-Danlos Syndrome Foundation learning conference were evaluated by questionnaire, clinical examination, and when indicated, radiographs. A database of 250 items per patient was constructed and statistically assessed using analysis of variance. Because of rarity of Types VII and VIII, these two patients were dropped from the analysis. Fifty-eight patients had Ehlers-Danlos syndrome Types I, II, III, or IV and form the study cohort. Among these four types, there were no significant differences in history of joint dislocation, swelling, or types of orthopaedic surgical procedures experienced. Thirty patients with Type III Ehlers-Danlos syndrome reported joint pain more frequently than did patients with Types I, II, or IV. Ambulation was impaired significantly in patients with Type III disorder as a whole, as was functional hand strength and upper extremity function. Back or neck pain was a common (67.2%) report among patients with all types of disease but did not correlate with the presence or absence of spinal deformity. Contrary to most previous reports, the patients in this study showed that Type III Ehlers-Danlos syndrome was the most debilitating form with respect to musculoskeletal function.

Results of tibial lengthening with the Ilizarov technique.

Between June 1987 and June 1992, 62 tibiae in 52 patients underwent lengthening by using the Ilizarov technique. Follow-up was from 18 months to 5 years. The mean age at surgery was 12.9 years (range, 5-19). The etiology of limb shortening was congenital in 53 and acquired in nine tibiae. Thirty-five tibiae had bifocal and 27 had unifocal treatment. Twenty-two of the 62 limbs had simultaneous treatment of other associated problems, including rotational or angular deformity or foot deformity. The average lengthening was 7.5 cm (range, 3.5-12), which was equivalent to a 32% average overall increase in limb-segment length (range, 6-96%). Complications required 28 (22%) unplanned procedures in the 62 tibiae, including nine osteotomies for iatrogenic malunion or deformation of regenerate bone (31%). Three tendo Achilles lengthenings and posterior ankle capsulotomies were required for persistent equinus contractures. Bony complications declined as experience with the technique increased. This technique allows simultaneous lengthening correction with control of the adjacent foot when required.

Results of femoral lengthening using the Ilizarov technique

We report the results of 36 femoral lengthenings in 30 consecutive patients using the Ilizarov technique. Patient age at surgery in 19 boys and 11 girls averaged 13.4 years (range, 5-18). Minimum follow-up was 2 years. The etiology of femoral shortening was congenital in 21 femora and acquired in 15. Twelve femora underwent concomitant correction of associated angular deformities during treatment. The average lengthening was 8.3 cm (range, 3.5-12 cm) with a treatment time of 6.4 months (range, 2.5-12). The mean number of surgeries per patient was 2.3, including apparatus application and removal. Lengthening index (months of treatment/centimeter lengthening) was 0.74. Complications included premature consolidation in four patients, malunion of > 10 degrees in two patients, and residual limb length inequality (< 2 cm) in two. There were two instances of knee subluxation [corrected]. No osteomyelitis, ring sequestra, neurologic or vascular compromise, compartment syndrome, hypertension, or hip or knee dislocations occurred. Psychological problems necessitated cessation of lengthening in two patients. These results show a significant improvement over previous reports of earlier techniques of femoral lengthening in terms of greater lengthening, simultaneous deformity correction, and fewer major complications.

Management of late-onset tibia vara in the obese patient by using circular external fixation

Previously published series of surgery for late-onset tibia vara reported a significant number of complications and fair or poor results. Obesity in many of these patients makes surgical intervention an even more daunting prospect. Circular external fixation is applicable to almost any limb size and allows weight bearing as tolerated, with gradual adjustment of alignment. Twenty-five tibiae in 17 patients who exceeded their ideal body weight by > or =50% underwent correction of late-onset tibia vara with the Ilizarov technique. Average age at surgery was 11 years 7 months (range, 7 years 8 months to 15 years 11 months). Mean varus deformity was 27 degrees (range, 10-55 degrees). Treatment time averaged 12 weeks in patients without lengthening and 16.9 weeks in those requiring lengthening (mean, 3.5 cm). All patients achieved alignment within 5 degrees of normal. Complications included one delayed union, premature consolidation in one, and two residual limb-length inequalities. There were no cases of osteomyelitis, compartment syndrome, or nerve palsy. These results are a significant improvement over reports of traditional methods in these difficult patients.

Syndrome of inappropriate antidiuretic hormone secretion in children following spinal fusion

OBJECTIVES a) To determine if antidiuretic hormone (ADH) is elevated in patients undergoing spinal fusion, especially in those who have clinical evidence of syndrome of inappropriate antidiuretic hormone (SIADH); b) to evaluate the relationship between ADH secretion and the secretion of atrial natriuretic peptide (ANP). SETTING Tertiary care pediatric intensive care unit (ICU) in a university hospital. DESIGN A prospective cross-sectional, observational study with factorial design. PATIENTS Thirty patients > or = 10 yrs of age undergoing spinal fusion admitted to the ICU for postoperative care. INTERVENTIONS Patients underwent anterior, posterior, or both anterior/posterior spinal fusion. Blood was collected for serial measurements of ADH, ANP and serum electrolyte levels. Heart rate, blood pressure and central venous pressure were measured. MEASUREMENTS AND MAIN RESULTS Thirty children were studied. Nineteen had idiopathic scoliosis, nine had neuromuscular scoliosis, one had Marfans disease, and one had congenital scoliosis. Ten (33%) children met clinical criteria of SIADH. There was no difference in duration of surgery, blood loss, volume of iv fluid administration pre- and intraoperatively, or type of scoliosis between those who developed SIADH and those who did not. Hemodynamic variables were similar in both groups. ADH levels increased in both groups immediately postoperatively and at 6 hrs after surgery, but were much more elevated in those patients with SIADH. Patients with SIADH also had significantly higher ADH levels preoperatively. In relation to serum osmolality, ADH was considerably higher in those with SIADH compared with those who did not. Although ANP values tended to be higher in the group with SIADH, this did not reach statistical significance. CONCLUSION SIADH occurs in a subset of children who undergo spinal fusion. The diagnosis of SIADH can be made easily using clinical parameters which are well-defined. In the face of SIADH, continued volume expansion may be harmful, and should therefore be avoided.

The Prognostic Value of Quantitative Bone Scan in Knee Osteochondritis Dissecans A Preliminary Experience

We reviewed the records of 12 patients ages 9 to 16 years with knee osteochondritis dissecans. All patients had clinical histories and examinations, four radiographic views of the knee, and technetium-99m diphosphonate quantitative bone scans. Scan results (symmetric, increased, or decreased activity), clinical course, healing time, and final outcome were correlated to determine the prognostic value of the scan. We divided the patients into those with open physes (distal femoral and proximal tibial) and those with closed physes. Four of the six patients with open physes had increased activity on the bone scan. All four of these knees healed with nonsurgical treatment. The other two patients had decreased activity on bone scan, and both required surgical treatment after nonsurgical treatment failed. Of the six patients with closed physes, all had increased activity on the bone scan, but only two patients had healing of the osteochondral lesion without surgery. Quantitative bone scanning had a 100% predictive value for the prognosis in osteochondritis dissecans patients with open physes, but for those with closed physes the predictive value was less. Because the natural history in the adolescent group is less predictable, it is in this group that the quantitative scan would be most helpful. In this small group of patients, quantitative bone scanning had limited prognostic value.

The effect of femoral lengthening on knee articular cartilage: the role of apparatus extension across the joint.

Loss of joint motion is a common complication of limb lengthening despite newer methods of incremental bone elongation. A pilot canine study has demonstrated that 30% femoral lengthening causes reproducible knee cartilage injury manifest by frank loss of cartilage substance or fibrillation. This study was undertaken to examine the potential of knee joint protection by apparatus extension to the tibia. Four dogs underwent application of a modified Ilizarov apparatus to the femur and tibia with coaxial hinges at the knee. After osteotomy, 30% lengthening was undertaken at 0.75 mm daily in three increments. At the completion of lengthening, experimental and contralateral knee joints were harvested, assessed grossly, decalcified, sagittally sectioned, and stained with safranin-O. All control joints were normal histologically. All experimental joints demonstrated a decrease in proteoglycan staining without evidence of fibrillation or necrosis. These findings suggest a protective effect of the tibial apparatus by avoiding joint compression.

Correction of proximal tibial deformities in adolescents with the T-Garches external fixator

Frontal-plane deformity of the proximal tibia in children has a variety of etiologies. There are also a number of described surgical techniques for correction of these deformities. The authors reviewed their early experience with the use of the Orthofix T-Garches external fixator for correction of 16 proximal tibial deformities in 14 patients. Mean age at surgery was 14.2 years. The most common diagnosis was adolescent Blounts disease. Average deformity was 12 degrees. Total treatment time averaged 13 weeks for those requiring lengthening and 10.8 weeks for those without. Complications included one ring sequestrum treated by curettage, and two patients with subsequent development of femoral deformity. Tibial anatomic axis averaged 1 degree of varus. This device can achieve excellent correction of deformity isolated to the frontal plane with few complications. It allows functional weight bearing and use of adjacent joints during treatment.

Femoral version in acute slipped capital femoral epiphysis.

Seven patients with seven acute slipped capital femoral epiphyses (SCFE) had computed tomography (CT) scan determination of femoral version. Version value differences were compared between the involved and uninvolved sides, and each was compared with a standard value for age. Comparison was also made with chronic slipped femoral version values. As compared to the standard of 20 degrees, the acute, involved side femoral version was 9.3 degrees (p = 0.057). Comparisons of involved and uninvolved sides showed no significant difference (p = 0.25). Analysis of differences of bilateral femoral version of patients with acute SCFE with that of patients with chronic SCFE version showed a significant difference (p = 0.009). Version in patients with acute SCFE more closely resembles the normal value than does that of patients with chronic SCFE, further emphasizing the uniqueness of the acute type of SCFE.

Relationship of factors affecting age of onset of independent ambulation.

Despite the standard available pediatric developmental scales and popular lore that girls walk at an earlier age than boys, no large-scale evaluation of the age of onset of independent ambulation has been previously published. The purpose of this study was the prospective epidemiologic evaluation of a large heterogeneous group of normal children to determine the effect of gender, race, birth order, and socioeconomic status on the age of onset of independent ambulation. The study cohort consisted of 986 children (575 male, 471 female). A multivariable analysis of covariance model was used to examine the effects of race, gender, income, and birth order on age at ambulation. After controlling for the other variables in the model, race was the only statistically significant predictor of age at ambulation (p < 0.0001), with black children walking at a younger age (10.9 ± 2.1 months) than white children (11.6 ± 2.3 months). Overall, the independent variables included in the model were only able to explain 2.5% of the variance of age at ambulation.