Impaired Mobility ICD-10 Codes: What You Need to Know

As a rehabilitation therapist, your role centers around restoring and improving your patients’ functionality. Whether you help your patients regain the skills needed to complete activities of daily living or focus on restoring range of motion following an injury, your expertise is crucial to helping them live a better quality of life. 

However, these actions alone aren’t the key to better patient outcomes. Clear and concise medical documentation, combined with accurate coding, are also essential components of delivering exceptional care. Within your profession, the impaired mobility ICD-10 codes are some of the most commonly used, so it’s important to understand how and when to use them. 

To ensure you’re up to speed, we’ll cover what you need to know to receive proper reimbursement and promote continuity of care. 

What Are Impaired Mobility ICD-10 Codes?

Developed by the World Health Organization (WHO), the tenth revision of the International Classification of Diseases (ICD-10) is a medical coding system for classifying conditions, injuries, and causes of death. This globally recognized system helps us better understand the causes and consequences of human disease and mortality.

However, several countries use their own variations of ICD-10 to ensure their unique healthcare infrastructures are also accounted for. In the United States, for example, the Centers for Medicare & Medicaid Services (CMS) and the National Center for Health Statistics (NCHS) created two ICD medical coding sets: ICD-10-CM  and ICD-10-PCs. 

ICD-10-CM

ICD-10-CM (Clinical Modification) are alphanumeric diagnosis codes that include three to seven characters. They’re used by all providers in U.S. healthcare settings to explain the diagnosis for the patients’ healthcare services. ICD-10 mobility impairment codes fall under the clinical modification category, so let’s dive a little deeper into these codes to facilitate a greater understanding. 

Diagnosis codes follow a specific format, which is as follows. 

• Characters 1 – 3: These characters represent the category of the diagnosis. The first character is always alpha (A,B,C, etc.), and the second one is always numeric (1,2,3, etc.). The rest can be any combination of the two. 
• Characters 4 – 6: These describe the etiology, anatomic site, severity, and other clinical details. 
• Character 7: This character is an extension value used to represent injuries and external causes to identify the encounter. It primarily focuses on the patient’s condition and the specific situations related to treating the condition. Many of the categories that require a seventh character fall under one of these three conditions.
  • A: Initial encounter (when the patient is getting active treatment for their condition but not necessarily the very first visit)  
  • D: Subsequent encounter (routine care of the condition or injury during the healing or recovery phase, such as rehabilitation) 
  • S: Sequela (added for conditions or complications that occur as a result of the injury or primary condition)  

ICD-10-CM codes are intended to be used and reported using the maximum number of characters available. They should also be reported with the highest level of specificity documented in the medical record, which relies on the medical documentation being clear. 

ICD-10-PCS

Following a seven-character alphanumeric code structure, ICD-10-PCS (Procedure Coding System) is used to monitor the medical procedures that practitioners perform in U.S. hospital inpatient settings. These codes follow a specific format, with each character having a distinct meaning. 

Understanding Impaired Mobility ICD-10 Billing Codes

Physical therapists and occupational therapists occasionally encounter challenges when coding for patients with impaired mobility, and rightfully so. For instance, if  you try to search for impaired mobility codes online, the information out there isn’t always super clear. Search engines will populate a few coding options that might seem relevant, but then you might feel uncertain about how and when to use  them for reimbursement. 

We recognize that these concepts can be confusing, but on a fundamental level, this is what you need to know: ICD-10 mobility impairment billing codes are designed to address the various ways an individual’s functions can be impaired. 

Common Factors Causing Mobility Impairment 

In your role, you’ll often work with patients who struggle to get out of bed, walk more than a few feet, or even propel their wheelchairs. From experience and training, you’ll understand that helping them improve their functionality requires knowing why they’re unable to complete a mobility-related task in the first place. Much like other medical professions, you’re looking to treat the root cause of the mobility hindrance.

 Causes for impaired functional mobility vary and could be due to any number of conditions, including the following: 

• Pain
• Balance issues
• Movement disorders
• Muscle tone changes
• Limited range of motion
• Decreased cardiovascular fitness 
• Motor control deficits 
• Loss of muscular endurance and/or strength 
• Problems with sensation, coordination, or kinesthesia 
• Inadequate or missing adaptive footwear, assistive devices, etc. 

When you don’t know the underlying cause of impaired mobility or fail to document causative factors properly, it can make planning and directing treatment challenging. Furthermore, failing to clarify why you’re performing certain interventions could lead to insurance claim denials and continuity of care issues. 

Z Codes: Their Role and Importance in Rehabilitation  

In rehabilitation, Z codes, a subset of ICD-10 codes are frequently used to report non-medical factors that influence the need for ongoing patient care. It acknowledges that sometimes it’s not a specific pathology causing a patient’s health to be affected. 

Z codes are unique in that they allow healthcare professionals to document personal, socioeconomic, or environmental factors affecting a patient’s health status. Essentially, it offers a broader scope of patient well-being, making it easier to provide more personalized care. 

This is important to rehab therapists, who often have encounters with patients that aren’t directly related to a specific condition or injury. Instead, there may be other circumstances affecting a patient’s health, such as their mobility. Physical therapists and similar professionals primarily deal with the after-effects of injuries, accidents, and medical conditions, rather than the injuries or conditions themselves. 

Z74.09: A Popular Impaired Mobility ICD-10 Code

One of the most commonly used ICD-10 codes in rehab therapy is Z74.09, which refers to “other reduced mobility.” This aftercare Z code applies to encounters where a patient experiences challenges with mobility due to various issues, which affect their ability to complete activities of daily living (ADLs). 

The term “chair-ridden” may be used in conjunction with this code to describe a patient who is likely unable to walk or stand for an extended period. Reduced mobility NOS (not otherwise specified) may also be documented with this code to denote patients with mobility challenges that don’t fall under a more specific diagnosis. 

You can think of Z74.09 as a mobility-related impairment catch-all code that rehabilitation therapists can use when others aren’t appropriate. For instance, if a patient experiences limited mobility after surgery or an extended period of bed rest following an injury, Z74.09 could be used if a more specific code isn’t appropriate. 

When Should Z74.09 Be Excluded? 

If a patient’s reduced mobility is due to being wheelchair-bound, then Z74.09 wouldn’t be appropriate. Instead, rehabilitation practices should use Z99.3, as that indicates wheelchair dependence. 

Additionally, if their reduced mobility is a result of a known medical condition, the specific diagnosis code for that condition should be used, rather than Z74.09. 

Circumstances Where Z74.09 May Be Denied

ICD-10 codes enable greater specificity, allowing you to capture more detailed information in a single code. However, Z74.09 is broad, so it’s possible that payers might deny a practitioner’s claim if they believe a more specific code is available. Remember to always apply the most specific code possible.

Other Z Codes for Reduced Mobility in Rehab Therapy

There is another Z code that physical therapists might use, which looks very similar to Z74.09, and that’s Z74.0. This code indicates reduced mobility, but note that it’s not intended for reimbursement purposes. That’s because the code itself isn’t considered specific enough, but there are codes below  that could be used instead. Those billable codes are as follows.

•  Z74.0: Bed confinement status
•  Z74.1: Need for assistance with personal care
•  Z74.2: Need for assistance at home and no other household member able to render care
•  Z74.3: Need for continuous supervision
•  Z74.8: Other problems related to care provider dependency (patient requires help from a caregiver)
•  Z74.9: Problem related to care provider dependency, unspecified

A Z Code for Fall Risks 

If you have a patient who has experienced falls or is at risk of future falls, consider using Z91.81. This billable code is for individuals with a high risk of falls and a history of falling. It lets others know that they should use preventative measures when working with them. 

Additional Mobility-Related Diagnosis Codes

To properly use ICD-10 codes, it is essential to consider the importance of specificity. There are situations where the Z codes for impaired or reduced mobility wouldn’t be appropriate. You should avoid coding patients with general mobility issues when more specific diagnoses are available. For instance, if you’re working with a patient who has challenges walking, they might have an underlying condition that should be coded first. 

So, how should your rehab practice approach coding a patient who is being seen for gait and mobility issues leading to  struggles with ambulation? Imagine a patient who isn’t wheelchair-bound or experiencing other impairment in ADLs.

In this scenario, it would be most appropriate to use a diagnosis that reflects the patient’s abnormalities in gait and mobility, for which the corresponding code is R26. However, the problem with this code is that it’s too broad and not specific enough to receive reimbursement. 

You’d need to look at the more specific, billable ICD-10 codes within the R26 code set, such as: 

• R26.0 (Ataxic Gait). This covers patients with a stumbling gait and uncoordinated walking. This may stem from impaired sensory or motor function, often associated with nervous system disorders. 
• R26.1 (Paralytic Gait). This code is for those patients with a spastic gait due to paralysis. 
• R26.2 (Difficulty in Walking, Not Elsewhere Classified). These patients have general challenges with walking, but this code excludes unsteadiness on feet and falling. 
• R26.81 (Unsteadiness on Feet), This code describes gait unsteady patients. 
• R26.89 (Other Abnormalities of Gait and Mobility), This code can be used to describe various types of gait issues that aren’t covered by other ICD-10 codes. Some synonyms include cautious gait, gait disorder due to weakness, painful gait, toe-walking gait, unsteady when walking, limp in childhood, and  others. 
• R26.9 (Unspecified Abnormalities of Gait and Mobility). This code refers to non-specific gait abnormalities. A few applicable synonyms include abnormal gait, functional gait abnormality, and gait abnormality. 
• R29.6 (Repeated Falls): This is indicated for patients who’ve recently experienced multiple falls in a short period of time, and the cause of  the fall is being investigated. This code excludes individuals at risk of falling or those with a history of falling.  In those cases, code Z91.81 should be used instead. 

Why Are ICD-10 Codes Important to Rehab Therapists?

One of the primary reasons rehabilitation therapists need to understand ICD-10 codes is the requirement to use them. 

According to the U.S. Department of Health and Human Services (HHS), all entities covered by the Health Insurance Portability and Accountability Act (HIPAA) are required to use the ICD-10 coding system. Therefore, if you’re a practice owner and want to ensure you receive payments from Medicare, Medicaid, and private insurance companies, it’s a necessity. 

However, does the same apply if you’re a cash-based practice whose patients receive the reimbursement directly from their insurer? The answer is yes. Cash-based businesses aren’t exempt from using ICD-10 codes, because you’ll still need to provide your patients with superbills, which include ICD-10 codes, so  they can file for reimbursement. 

In addition to ensuring providers receive payments, ICD-10 codes also allow payers and providers to: 

• Observe and improve provider performance (consider value-based programs, which could tie into incentive payments if you’re delivering great quality of care). 
• Measure patient safety and efficacy. 
• Evaluate healthcare costs.
• Review risk factors for specific populations. 

Bonus Tip: Make Strides to Code Properly  

Keep in mind that it’s not just important to use ICD-10 codes; it’s vital that you use them correctly. If your documentation is vague, it could be challenging for a medical coder to accurately capture what occurred  during a patient encounter. In these situations, they may use an unspecified code leading to denied payment.

To minimize denials, optimize reimbursements, and even receive payments faster, consider leveraging technology. In recent years, robust electronic health records (EHRs) have been designed to help practitioners create defensible documentation that’s paired with the correct codes. When you automate certain workflows, you can save your practice several hours, allowing you to run more efficiently and profitably. 

Feel Confident Using Impaired Mobility ICD-10 Codes

If you’ve ever felt confused about using ​​impaired mobility ICD-10 codes, you’re not alone. Several rehab practice owners question if they’re using them correctly, and even worry that trying to figure out proper coding is cutting into time meant for patient care. This is why we prepared this overview. We want to help rehab therapists better understand and navigate the complexities of ICD-10 impaired mobility codes. 

However, understanding is just half the battle. The other part is implementation. Company leaders hoping to maintain patient care as the primary focus while maximizing reimbursements should assess how technology can benefit their business.