Preoperative Gallows traction as an adjunct to hip open reduction surgery: Is it safe and is it effective?

Abstract

Background: Traction is used at our hospital before open reduction in infants with developmental dysplasia of the hip. Theoretically, it reduces soft-tissue tension, allowing an easier surgical reduction and therefore lower surgical complications. Owing to extended hospital stays, potential complications, and lack of evidence, the use of traction has decreased. This study aims to quantify whether traction is safe and whether it has any demonstrable effect.

Methods: The perioperative course of 80 patients undergoing preoperative traction and hip open reduction were reviewed. The height of hip dislocation was classified using the International Hip Dysplasia Institute classification system on both radiographs taken before and after traction. Any complications related to traction were recorded, along with the requirement for femoral shortening osteotomies, incidence of re-dislocation, and longer-term rate of avascular necrosis.

Results: Traction lowered the resting position of the majority of hips, with the median International Hip Dysplasia Institute grade before traction improving from 4 to 3, a statistically significant improvement (p < 0.00001). There were no neurovascular complications. Two babies were complicated with broken skin sores; however, surgery still progressed uneventfully. Zero hips in the cohort required femoral shortening osteotomies to achieve a tension-free reduction, and the re-dislocation rate was 0%. However, 96% of hips were Severin 1 or 2 at 6-year follow-up.

Conclusion: Notably, 1 week of preoperative traction significantly improves the resting position of the hip in high dislocations. It is safe when used in infants weighing <12 kg, and subsequent surgical outcomes are excellent, thus supporting its use ahead of developmental dysplasia of the hip open reduction surgery.

Level of evidence: Level IV.

Keywords: Developmental dysplasia of the hip; Gallows traction; avascular necrosis; preoperative traction.

Figure 1.

An infant happily undergoing Gallows traction ahead of hip open reduction surgery.

Figure 2.

(a) Radiological imaging outlining the IHDI classification system for hip position in DDH. The Right hip is normal and is IHDI I. The left hip is dislocated and is IHDI III. (b) A bar chart showing the resting position of each hip according to the IHDI classification system, both before and after traction. The red section shows the number of hips at IHDI grade IV, amber is for Grade III hips and green is for Grade II.

Figure 3.

(a) Preoperative and pre-traction radiograph of a 13-month-old infant. The left hip is a high IHDI 4 hip. The right hip is also affected, to a lesser extent, and is IHDI 2. (b) Post-traction radiograph performed 7 days later, at rest with the traction removed, with the image intensifier before any surgery has commenced. Hilgenreiner’s line is plotted on both radiographs to illustrate the different resting positions of the hip. The left hip has improved from IHDI 4 to 3. The right hip is IHDI 2 on both radiographs, although can be seen to be nearer the anatomical level post-traction.

Figure 4.

(a) Severin grade at mean of 6-year follow-up. Notably, 40 hips were Severin 1 (normal appearance), 37 hips were Severin 2 (mild deformity of the femoral head or neck or acetabulum), 2 hips were Severin 3 (dysplastic without subluxation), and 1 hip was Severin 4 (subluxed), (b) AVN grade using the Kalamchi and MacEwen classification system at mean of 6-year follow-up. Notably, 55 hips were Grade 0/1 (no AVN/delayed appearance or mild irregularity of ossific nucleus but with no long-standing change to development), 11 hips were Grade 2 (lateral growth arrest), 9 hips were Grade 3 (central necrosis), and 5 hips were Grade 4 (whole-head necrosis). (c) Avascular grade using the Salter classification system at mean of 6-year follow-up. Notably, 61 were Grade 0 (no evidence of AVN), 1 hip was Grade 1 (no ossific nucleus after 1 year post-reduction), 6 hips were Grade 2 (failure of growth in an existing ossifying nucleus for ≥ 1 year post-reduction), 9 hips were Grade 3 (broadening of the femoral neck), 2 hips were Grade 4 (fragmentation of the femoral head), and 1 hip was Grade 5 (residual deformity after reossification).

Figure 5.

(a) Bar chart showing the preoperative resting position of 10 hips that did not undergo preoperative traction. The first column is the standard departmental radiograph and the second column is the comparative film under GA but before any surgery. The red section is IHDI Grade IV hips and amber is for the Grade III hip. There is no change in the position on any hip, thus excluding the effect of GA on the cohort of hips that had preoperative traction in this study, (b) this is illustrated, and (c) with no difference seen. This should be compared to Figure 3, where the difference in resting hip position after traction is clear.