A straightforward inexpensive method for hip cast immobilization in infants and children

Abstract

Backgrouds

Developmental dysplasia of the hip (DDH) represents the most prevalent hip disorder in children. A variety of methods for spica cast immobilization have been described using specialized equipment. This study attempts to explore an effective tool for spica cast immobilization.

Methods

We retrospectively analysed a total of 216 children who were diagnosed with DDH and underwent spica cast immobilization in our hospital from January 2018 to December 2023. They were divided into the group A (use of a bamboo stick) and group B (use of the hip spica table). The statistical analysis was conducted on preoperative data, procedure time, and major complications following spica cast immobilization.

Results

A total of 101 children in group A and 115 children in group B underwent spica cast immobilization. There was no statistically significant difference in general preoperative data (gender age, weight, medical history, or affected side) and procedure time. The mean number of polymer bandages consumed in group A was 7.8 ± 0.4 rolls, and 7.9 ± 0.5 rolls in group B. There was no statistically significant difference between the two groups. There was no statistical difference in complications (including superficial skin injury, extensive rash, and cast contamination).

Conclusion

The bamboo stick represents a portable, safe, and cost-effective alternative to the hip plaster operating table. This method can be applied in spica cast immobilization in children.

Introduction

Developmental dysplasia of the hip (DDH) represents the most common hip disorder in children, with a prevalence ranging from 0.1‰ to 6.6‰ [1]. This condition encompasses a range of abnormalities, including hip dislocation, subluxation, and acetabular dysplasia [2]. The treatment of DDH emphasises the importance of early detection and intervention. Earlier treatment is associated with better outcomes. The principals in treatment of DDH are to achieve central repositioning, to maintain stable repositioning, to promote normal growth and development of the hip joint, and to reduce complications. In our institution, for children with DDH between the ages of 6 and 18 months who undergo closed reduction, immobilization in a spica cast is a standard treatment option.

The human position is defined as a range of hip flexion between 95° and 100°, a range of abduction between 40° and 50°, and rotational neutrality [3]. This type of human positional cast immobilization of the hip is a standard method for treatment DDH. Usually, surgeons use specialized plaster beds to perform the immobilization. Currently, bed is fewer and more expensive to purchase on the market. Here, we describe and evaluate the application of a simple bamboo stick tool for immobilization of the hip. To our knowledge, this is the least expensive and simplest tool for hip immobilization in children. The purpose of this study was to prove the effectiveness of this method.

Patients and methods

Patients

A total of 216 patients diagnosed with DDH underwent human positional cast immobilization in our hospital from January 2018 to December 2023. The patients consisted of 180 females and 36 males aged 12.3 ± 3.6 months (ranging from 6 to 18 months). Bilateral disease was seen in 65 patients; left side, 92 patients; right side, 59 patients. Inclusion criteria were: 1) aged 6 months to 18 months diagnosed with DDH, 2) did not have any other comorbidities, 3) admitted at our hospital and placed in intraoperative spica cast immobilization in the human position, and 4) patients who had complete clinical data. Exclusion criteria were 1) presence of other diseases; 2) aged younger than 6 months or older than 18 months 3) seen in outpatient clinics using various types of braces without human positional plaster immobilization, 4) hip could not be successfully reset, and 5) incomplete or lost follow-up data.

Surgical procedure

Under general anaesthesia, the child had a cotton liner placed for both lower limbs and the torso. Additionally, a long strip of towel was placed inside the cotton liner from the epigastrium to the perineum (or scrotum).

Group A: The initial step involved the placement of a bamboo stick with relatively flat and narrow ends, commonly used for transporting loads. Bamboo was chosen for its favorable combination of strength, toughness, elasticity, wide availability, and low cost. (Figure 1). The bamboo was placed between the operating bed and a table that had been padded with therapeutic wipes (it is placed between two tables of the same height). Then, the patient’s head and the back of the upper chest are positioned horizontally on the surgical bed. The lumbar spine and sacrococcygeal region are positioned on the bamboo stick between the two tables, with the assistant providing support for the child’s lower limbs. This ensures that the hip joint is maintained in a position of 95°-100° flexion, 40°-50° abduction, and neutral rotation, thereby keeping the femoral head within the acetabulum. Subsequently, a cotton pad was wrapped around the child’s trunk, lower limbs, abdomen, hips, thighs, and calves, with particular attention paid to the protection of bony prominences such as the sacrum, both iliac crests, patella, fibular tuberosity, and anterior tibial margin. A polymer immobilizing bandage (Prime Medical Inc., South Korea, 7.5 cm in width, and 3.6 m in length) was then used to tie and wrap around the child’s hips. The wrapping process was conducted in a fixed sequence of stages. The initial step was to immobilize both hips to just below the knee. Subsequently, both calves were immobilized (with particular attention paid to both inguinal areas and the affected greater trochanteric area during the shaping process). Once the polymer bandage had undergone the necessary hardening process, the bamboo stick was carefully withdrawn from the area between the child’s back and the herringbone cast. This was achieved by rocking the bamboo stick from side to side, allowing the operator to precisely trim the perineal cast (The preservation of the sacrococcygeal area and anterolateral opening is necessary to facilitate the child’s urinary and bowel care). Concurrently, the margins of the excised hip herringbone cast were wrapped with elastic tape, thereby guaranteeing the ability to insert a diaper into the hip herringbone cast (for further clarification, please refer to Figure 3). Finally, intraoperative C-arm radiography was performed to confirm hip reduction.

Figure 1.

Bamboo stick used for group A.

Figure 3.

Flow of hip cast immobilization in the bamboo stick group (①②③④⑤).

Group B: The patient is positioned in a supine position on a specialized plaster operating table (a locally customized hip herringbone plaster operating table is illustrated in Figure 2). An assistant supports both of the child’s lower limbs, and the surgeon immobilizes the child in a human positional cast (cotton pads are wrapped and polymer fixation bandage is formed as for group A).

Figure 2.

Local customized plaster operating table.

Postoperative management and follow-up

All patients were followed, and the polymer bandage was changed again once at six weeks postoperatively. During this period, the family of the patients paid close attention to patient care. In the event of an adverse reaction, such as a failure of the hip reset, a broken hip cast, a severe odor (caused by urine and fecal contamination), a skin injury, or a cast indentation, the cast was replaced promptly. In the absence of the aforementioned factors, the standard practice was to remove the cast and rehumanize the cast immobilization, typically six weeks postoperatively.

Statistical analysis

The data were analysed by SPSS (20.0 IBM. USA). The t-test was employed for continuous information, whereas the χ² test or Fisher’s exact probability method was utilized for categorical data. p < 0.05 was considered statistically significant.

Ethics approval and consent to participate

This study was performed in line with the principles of the Declaration of Helsinki. Approval was granted by the Ethics Committee of Children’s Hospital of Chongqing Medical University [No. CHCMU-2024-458]. In the present study, written informed consent was obtained from the parents or legal guardians of all participants.

Results

Patients numbering 216 with DDH were included in this study, and a total of 458 human positional cast immobilization were performed in our hospital. In group A, 101 patients underwent 213 human position plaster immobilizations, while 115 patients in group B underwent 245 human position plaster immobilizations. No difference was found between the two groups in gender, age, weight, or the condition of the affected limb. (Table 1)

Table 1.

Preoperative, intraoperative and postoperative analysis of the groups.

	Group A (Bamboo stick)	Group B (Plaster)	statistical value	P-value
plaster cast(times)	213	245
Sex			χ2 = 0.450	0.502
Patients(n=216)	101	115
Male	15(14.85%)	21(18.26%)
Female	86(85.15%)	94(81.74%)
affected limb(n=216)			χ2 = 0.353	0.838
Bilateral	30	35
Left side	45	47
Right side	26	33
Age (months)	11.9 ± 3.7	12.5 ± 3.4	t=-1.734	0.084
Weight (Kg)	9.9 ± 1.2	10.1 ± 1.0	t=-1.738	0.075
Operative time for plaster immobilization(hour)	0.56 ± 0.14	0.54 ± 0.15	t=1.642	0.101
Single use of polymer bandage(roll)	7.8 ± 0.4	7.9 ± 0.5	t=-1.756	0.08
Associated Plaster Complications (case)	17	22	χ2=0.192	0.661
Re-dislocation (case)	2	3	χ2=0.094	0.759
AVN(case)	12	15	χ2=0.66	0.697

Statistical significance was set at p < 0.05.

The mean time for the plaster immobilization in group A was 0.56 ± 0.14 h, while in group B it was 0.54 ± 0.15 h. There was no statistically significant difference. Additionally, the mean number of polymer bandages utilized in the intraoperative by the group A was 7.8 ± 0.4 rolls, while group B was 7.9 ± 0.5 rolls, demonstrating no statistically significant difference (Table 1).

A total of 17 patients with postoperative complications were identified in group A, compared to 22 patients in group B, which was not a statistically significant difference. Regarding the primary outcome of hip stability, there were two cases of re-dislocation in Group A and three cases in Group B; however, there was no statistically significant difference between the two groups (p = 0.759). (Table 1). There were 11 patients with superficial skin injury, 3 patients with extensive rash, no patients with skin pressure sores, 3 patients with urine and faecal contamination, and no patients with breakage of the plaster in group A. There were 15 patients with superficial skin injuries, 2 patients with extensive rashes, 4 patients with urine and faecal contamination, and no patients with pressure sores on the skin. Additionally, there was one patient with fracture and breakage of the plaster.

Discussion

This study demonstrates that a bamboo stick is an effective hip cast immobilization tool compared to a plaster operating table. It was easily purchased, carried and inexpensive. Spica cast immobilization has been demonstrated to be an effective treatment for DDH. However, the procedure needs utilization of specialized tables. The tables are used to support the patient’s trunk and sacrum while the cast is placed. Many scholars have initiated the design and patent application process for the tables [4–6]. In a survey of the Gulf region, Ammar et al. found that the company’s hip operating tables are perceived as expensive and not widely recognized or popularized by surgeons. Additionally, a notable proportion of surgeons still locally customise these tables [7].

In the current literature, various hip cast immobilization procedures and cast manipulation tables are described, Fraser et al.⁸ proposed a suspension bed technique using soft materials; however, this arrangement does not provide adequate support for the sacrococcygeal region. Other described methods include using an operating table armboard (requiring additional assistant support) [9], a custom box-and-rod table (less portable) [10], a set of multiple pads (not portable) [11], and a table with an acrylic plate (which may be difficult to remove after casting) [12]. Compared to these methods, the bamboo stick used in this study provides adequate stabilization, is highly portable, inexpensive, and readily available.

The stick used in this study was made of bamboo and exhibits sufficient resistance to breakage, as well as a certain degree of toughness and elasticity. It provides adequate support for the sacrococcygeal region while not necessitating a specialized base. Resting between two flat surfaces of equal height is sufficient. Also, it can be found everywhere, is easy to buy and inexpensive. A significant advantage of the bamboo stick is its cost-effectiveness. The primary cost of the specialized plaster operating table can range from hundreds to thousands of dollars, not including maintenance and storage. In contrast, a bamboo stick is nearly ubiquitous and incurs negligible cost. Furthermore, its portability eliminates the need for dedicated storage space and facilitates use in different operating rooms or resource-limited settings, reducing indirect logistical costs.

The operating table used for group B was essentially the same as the local customized hip cast tabletops from the Gulf Area provided by Ammar et al. No significant differences were found in preoperative characteristics, intraoperative time or complications postoperatively. Furthermore, we have made improvements to the process of operating the plaster bundles. The initial step involves the polymer bandage performing three to five cycles of figure-of-eight cross-wrapping of the hip in both the posterior and anterior directions (Figure 4). This method is analogous to the figure-of-eight bandage fixation technique employed for clavicle fractures, which is a straightforward and routine procedure. The subsequent polymer wrapping sequence is in accordance with the description provided by Kumar [13]. It is our contention that this anterior-posterior cross-wrapping of the hip is consistent with the anterior cross plasterboard of the hip described by Bitar [14]. Furthermore, we also cross-wrapped the hip posteriorly, which has been demonstrated to be an effective method for preventing re-dislocation of the hip joint and increasing the stability and strength of the cast. Concurrently, the four-point plasticity of the bilateral greater trochanter, pubic symphysis, and sacrococcygeal region [15] was considered during the polymer bandage’s formation, as it facilitates the reset and stabilization of the hip joint.

Figure 4.

Anterior-posterior cross cast wrapping process of the hip.

The solid blue line represents the polymer bandage wrapped around the front of the body. The red dotted line indicates the back of the body, where Fig. ① indicates the back of the figure-of-eight cross-wrapping and Fig. ② indicates the front of the figure-of-eight cross-wrapping.

A long strip of towels was placed from the child’s abdomen to the perineum anteriorly prior to the application of a plaster cast. This was done to preserve sufficient space and reduce abdominal pressure, thereby preventing superior mesenteric artery syndrome (plaster cast syndrome) [16]. It also facilitated postoperative breathing and eating. This approach effectively circumvents the need for an unnecessary postoperative opening of the abdominal cast or placement of a ring anterior to the abdomen, as illustrated by the methodology of Kiter et al. [17] which is both complicated and potentially ineffective.

In this study, both groups of patients exhibited postoperative skin complications, which may be attributable to the absence of a waterproof liner during the intraoperative period [18,19] This is a costly and scarce resource, with limited manufacturers and availability. The children were subjected to a standard protocol of immobilization in a cast for a period of six weeks, followed by a second cast change and subsequently by a brace. The duration of cast immobilization was relatively brief. Most complications were superficial skin injuries with mild symptoms. These injuries were successfully treated with effective intervention and fully recovered within 1–3 days.

There were some limitations in this study. First, this was retrospective and further prospective or a multicentre study should be performed in the future. Second, the follow up time was not long enough, and long-term complications should be studied. Thirdly, the cast operation table was only one type, we did not compare it to others. Lastly, the age range of our cohort (6–18 months) was selected as it represents the typical window for closed reduction and spica cast immobilization at our institution. This limits the generalizability of our findings to younger infants for which harnesses are used or older children who may require surgical intervention.

Conclusion

The bamboo stick represents a portable, safe, and cost-effective alternative to the hip cast operating table.

Funding Statement

No funding was received for this work.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available from the corresponding author upon reasonable request.