Ankle Deformity Secondary to Acquired Fibular Segmental Defect in Children

BACKGROUND: The authors report the long-term effect of acquired pseudoarthrosis of the fibula on ankle development in children during skeletal growth, and the results of a long-term follow-up of Langenskiold's supramalleolar synostosis to correct an ankle deformity induced by an acquired fibular segmental defect in children. METHODS: Since 1980, 19 children with acquired pseudoarthrosis of the fibula were treated and followed up for an average of 11 years. Pseudoarthrosis was the result of a fibulectomy for tumor surgery, osteomyelitis of the fibula and traumatic segmental loss of the fibula in 10, 6, and 3 cases, respectively. Initially, a Langenskiold's operation (in 4 cases) and fusion of the lateral malleolus to the distal tibial epiphysis (in 1 case) were performed, whereas only skeletal growth was monitored in the other 14 cases. After a mean follow-up of 11 years, the valgus deformity and external tibial torsion of the ankle joint associated with proximal migration of the lateral malleolus needed to be treated with a supramallolar osteotomy in 12 cases (63%). These ankle deformities were evaluated using the serial radiographs and limb length scintigraphs. RESULTS: In all cases, early closure of the lateral part of the distal tibial physis, upward migration of the lateral malleolus, unstable valgus deformity and external tibial torsion of the ankle joint developed during a mean follow-up of 11 years (range, 5 to 21 years). The mean valgus deformity and external tibial torsion of the ankle at the final follow-up were 15.2degrees (range, 5degrees to 35degrees) and 10degrees (range, 5degrees to 12degrees), respectively. In 12 cases (12/19, 63%), a supramalleolar corrective osteotomy was performed but three children had a recurrence requiring an additional supramalleolar corrective osteotomy 2-4 times. CONCLUSIONS: A valgus deformity and external tibial torsion are inevitable after acquired pseudoarthrosis of the fibula in children. Both Langenskiold supramalleolar synostosis to prevent these ankle deformities and supramalleolar corrective osteotomy to correct them in children are effective initially. However, both procedures cannot maintain the permanent ankle stability during skeletal maturity. Therefore any type of prophylactic surgery should be carried out before epiphyseal closure of the distal tibia occurs, but the possibility of a recurrence of the ankle deformities and the need for final corrective surgery after skeletal maturity should be considered.

Utility of Preoperative Distractive Stress Radiograph for Beginners to Extent of Medial Release in Total Knee Arthroplasty

BACKGROUND: This study evaluated the preoperative distractive stress radiographs in order to quantify and predict the extent of medial release according to the degree of varus deformity in primary total knee arthroplasty. METHODS: We evaluated 120 varus, osteoarthritic knee joints (75 patients). The association of the angle on the distractive stress radiograph with extent of medial release was analyzed. The extent of medial release was classified into the following 4 groups according to the stage: release of the deep medial collateral ligament (group 1), release of the posterior oblique ligament and/or semimembranous tendon (group 2), release of the posterior capsule (group 3) and release of the superficial medial collateral ligament (group 4). RESULTS: The mean femorotibial angle on the preoperative distractive stress radiograph was valgus 2.4degrees (group 1), valgus 0.8degrees (group 2), varus 2.1degrees (group 3) and varus 2.7degrees (group 4). The extent of medial release increased with increasing degree of varus deformity seen on the preoperative distractive stress radiograph. CONCLUSIONS: The preoperative distractive stress radiograph was useful for predicting the extent of medial release when performing primary total knee arthroplaty.

Contralateral total knee arthroplasty after unilateral surgery in bilateral varus gonathrosis.

The authors retrospectively evaluated the rate of contralateral total knee arthroplasty (TKA) in 93 patients who had bilateral varus gonarthrosis and underwent unilateral TKA. Patients were divided into 3 groups according to degree of anatomical varus of the contralateral knee and/or contralateral knee pain at the time of first TKA. Group A, 25 patients, had no pain and within 10-degree deformity. Group B, 48 patients, had pain and within 10-degree deformity. Group C, 20 patients, had pain and more than 10-degree deformity. At a minimum of 2-years follow up after the first TKA, the mean function scores among the groups were significantly different (p < 0.0001). Seventy-five percent of group C, 34% of group B and 0% of group A underwent sequential contralateral TKA, respectively at average 6.7-month interval. Rate of contralateral TKA was high if patients had contralateral knee pain and more than 10 degrees of anatomical varus.

Rotational deformity of the distal humerus in cubitus varus.

The medial rotation deformity of the distal humerus usually exists in the cubitus varus deformity but has received little attention. Study of this deformity in 29 cases of cubitus varus was carried out using the osteotomized bony specimens that were removed during closed wedge osteotomy in order to determine the actual bone deformity. The average duration of the varus deformity was 5.6 yrs (range 1 to 11). The medial rotation deformity of the distal humerus averaged 27 degrees (range 15 to 45). There was no correlation between the degree of rotation and that of the varus deformity (correlation coefficient r = 0.15). The affected-side shoulder compensated well in both internal and external rotation, and had a greater arc of rotation than that of the normal side. The affected-side shoulder exhibited an internal rotation deformity with an average of 16 degrees (range 5 to 25), with restriction of external rotation of only 13 degrees (range 0 to 20) in comparison to normal side shoulder.