结论：给儿童做辅具，尺寸问题比成人复杂一个量级

成人的身体尺寸基本稳定，辅具配好之后可以用很多年。儿童在成长，而且成长速度快、个体差异大。

这带来一个矛盾：辅具要当下合适（否则影响姿势和功能），又要能跟随成长（否则频繁更换负担过重）。 两者的平衡是儿童辅具设计的核心问题。

另外，儿童康复辅具的使用者往往有发育方面的问题，不合适的辅具可能加重畸形，所以适配不只是舒适问题，而是治疗效果问题。

适配涉及的尺寸

尺寸 影响
座宽 过宽姿势不稳，过窄压迫
座深 过深压迫腘窝，过浅支撑不足
靠背高度 与躯干控制能力匹配
扶手高度 影响上肢支撑与姿势
脚踏高度 影响下肢角度与坐压分布
头枕位置 与头部控制能力匹配
侧支撑位置 与躯干形态匹配

这些尺寸不是独立的，调整一项会影响其他项。比如脚踏高度变化会改变大腿的受力分布，进而影响座深的适宜值。

成长调节的设计

支持成长的方式主要有几种：

可调节。 各尺寸在一定范围内可调。这是最常见的方式。

可更换部件。 更换座面、靠背等部件以适应更大尺寸。

模块化。 通过模块组合覆盖更宽的尺寸范围。

分档产品。 按年龄或身高分几个规格，超出后换产品。

设计上的关键问题是：调节范围有多大、调节是否方便、调节后是否可靠。

调节范围过大会带来结构上的代价 ——结构变重、刚度下降、成本上升。所以调节范围与产品定位相关，不是越大越好。

调节机构的可靠性

可调节产品的一个风险是：调节机构在使用中意外松动或滑移。

儿童使用的产品，这个风险的后果可能更严重，因为儿童无法判断和表达异常。所以调节机构的验证要重点做：

锁定可靠性。 调节后在载荷和振动下不移动。

防误调。 儿童自己或他人误触不应改变设定。

调节的可重复性。 有刻度或定位，便于记录和恢复设定。

耐久。 反复调节后锁定能力是否保持。

调节到极限位置的强度。 调到最大位置时结构是否仍然安全。

最后一项容易被忽略。 调节到极限位置时，悬臂变长、连接处受力增加，强度可能低于中间位置。强度试验应当在极限位置做，而不是中间位置。

测试上的特殊考虑

试验载荷。 按适用的体重范围确定，并考虑儿童可能的活动强度。儿童活泼好动，动态载荷可能相对更大。

试验人体模型。 需要符合儿童体型的模型，用成人模型做出来的数据不适用。

多种调节状态。 在不同的调节位置分别测试，特别是极限位置。

稳定性。 儿童的活动幅度大，稳定性要求应当考虑这一点。

小部件与可拆卸件。 儿童可能把小部件放入口中，需要考虑相关的安全要求。

尖锐边缘与夹持。 儿童的手指更小，间隙评价要按儿童尺寸做。

第五项和第六项是儿童产品特有的考虑，在成人产品的测试清单里通常没有，但对儿童产品是必要的。

与治疗目标的关系

儿童康复辅具往往同时是治疗工具，适配要服务于治疗目标：

姿势矫正。 侧支撑、髋部定位的位置要按具体的姿势问题设定。

功能促进。 座椅角度、扶手位置影响上肢活动能力。

预防畸形。 长期的姿势支持影响骨骼发育。

参与活动。 高度、角度影响儿童能否参与同龄人的活动。

所以适配不是纯粹的尺寸匹配，需要治疗师参与。 产品设计应当支持这种个体化调整——调节范围要够、调节要便于专业人员操作、设定要能记录。

说明书与随访

儿童辅具的资料应当包括：

适用的年龄或身高体重范围；各尺寸的调节范围与方法；调节后的检查要点；随成长调整的提示——建议多久复查一次适配情况；以及超出调节范围后的处理。

「随成长复查」这一条很重要，因为儿童成长是持续的，而家长可能不会主动想到辅具需要调整。资料中给出明确的复查建议，能提醒家长和照护者。

姿势支持件的验证

儿童辅具上的侧支撑、头枕、胸带、髋部定位件等姿势支持件，需要单独验证：

强度。 儿童可能用力靠压，支持件要能承受。

位置调节的范围与可靠性。 位置要能精确设定并保持。

接触面的压力。 支持件承受持续的侧向力，接触面压力关系到皮肤安全。儿童皮肤更脆弱，这一项要求更高。

边缘与形状。 不应有压迫点或尖锐边缘。

可拆卸性。 便于清洁和调整。

与成长的适配。 位置能否随成长调整。

「接触面压力」在姿势支持件上容易被忽略，因为它不像坐垫那样明显。但侧支撑长时间压在肋部，压力集中同样会造成损伤。建议做压力分布测量。

与家庭使用的配合

儿童辅具多数在家庭中使用，家长是主要操作者：

操作的简便性。 家长不是专业人员，调节和使用应当简单。

误操作的防护。 设定错误不应导致危险。

清洁的便利性。 儿童使用中污染较多，清洁要方便。

外观。 儿童产品的外观影响儿童的接受度和社会参与，不是纯粹的审美问题。

培训材料。 图示化的操作说明比文字更有效。

建议提供简明的操作图示并贴在产品上，家长在使用中随时能看到，比翻说明书实际。

我们的做法

做儿童辅具测试时，我们会在多个调节位置分别测试，特别是调到极限位置的状态 ——因为这是结构最不利的状态，也是儿童长大后实际会用到的状态。

另外，间隙和小部件相关的评价我们会按儿童的尺寸特征做，而不是沿用成人产品的判定。这两类风险对儿童产品是实质性的。

如果你有儿童康复辅具需要安排测试，想先理清测试状态和项目，可以把产品资料和适用范围发过来一起讨论，或者直接联系：132 4819 8029。检测能力见服务介绍，产品分类见手动轮椅检测与电动轮椅检测，案例见案例。

English version

Conclusion. Adult body dimensions are essentially stable, so once an assistive device is fitted it serves for years. Children grow, quickly and with wide individual variation. That creates a tension: the device must fit now, or posture and function suffer, and must also follow growth, or replacement becomes too frequent and too costly. Balancing the two is the central problem in designing paediatric assistive devices. Moreover, children using rehabilitation devices often have developmental conditions, and a poorly fitting device can worsen deformity, so fit is not a matter of comfort but of therapeutic outcome.

Dimensions involved. Seat width, where too wide leaves posture unstable and too narrow compresses. Seat depth, where too deep compresses the popliteal area and too shallow gives insufficient support. Backrest height, matched to trunk control. Armrest height, affecting upper limb support and posture. Footplate height, affecting lower limb angles and seat pressure distribution. Headrest position, matched to head control. And lateral support position, matched to trunk shape. These dimensions are not independent: adjusting one affects the others, and changing footplate height alters thigh loading and hence the appropriate seat depth.

Designing for growth. Several approaches exist. Adjustability allows dimensions to vary within a range, and is the most common. Replaceable components allow seat and backrest to be changed for larger sizes. Modularity covers a wider size range through combinations. And size bands provide several versions by age or stature, replaced when outgrown. The key design questions are how wide the adjustment range is, how convenient adjustment is, and how reliable it remains afterwards. A very wide range carries structural cost in weight, stiffness and price, so the range relates to product positioning rather than being better for being larger.

Reliability of adjustment mechanisms. One risk in adjustable products is the mechanism loosening or slipping in use. For paediatric products the consequences may be more serious, since children cannot judge or report a problem. Verification should therefore concentrate here. Locking must hold under load and vibration. Protection against unintended adjustment must prevent a child or others changing the setting by accident. Repeatability of adjustment, through scales or detents, lets settings be recorded and restored. Durability determines whether locking holds after repeated adjustment. And strength at the extremes of adjustment must be verified. The last is easily overlooked: at maximum extension the cantilever lengthens and connections carry more load, so strength may be lower than at intermediate positions. Perform strength testing at the extremes rather than mid-range.

Testing considerations. Test loads are set from the applicable weight range with allowance for the intensity of children's activity, which tends to make dynamic loads relatively larger. Test dummies must match child proportions, since data from adult dummies do not apply. Several adjustment states should be tested, the extremes especially. Stability requirements should reflect children's wider range of movement. Small and detachable parts require attention because children may put them in the mouth. And sharp edges and gaps must be assessed against children's smaller finger dimensions. The last two are specific to paediatric products, absent from adult test lists yet necessary here.

Relationship to therapeutic goals. Paediatric rehabilitation devices are often therapeutic tools as well, and fit must serve the therapeutic aim. Postural correction requires lateral and pelvic supports positioned for the specific postural problem. Functional facilitation depends on seat angle and armrest position affecting upper limb activity. Deformity prevention arises from long-term postural support influencing skeletal development. And participation depends on height and angle determining whether the child can join peers' activities. Fit is therefore not purely dimensional matching and requires therapist involvement, so the design must support individualised adjustment with adequate range, convenient professional adjustment and recordable settings.

Instructions and review. Documentation should state the applicable age or stature and weight range, the adjustment range and method for each dimension, check points after adjustment, prompts to adjust as the child grows including how often fit should be reviewed, and what to do once the adjustment range is exhausted. The growth review prompt matters, because children grow continuously while parents may not think of adjusting the device, and an explicit recommendation reminds families and carers.

How we handle it. For paediatric devices we test at several adjustment positions, the extremes in particular, since that is the structurally least favourable state and the one the child will actually reach on growing. We also assess gaps and small parts against children's dimensional characteristics rather than carrying over adult judgements, both risks being material for paediatric products.

Send us the product information and intended range and we will define the test states and items. Phone or WeChat: +86 132 4819 8029.