Fibrous dysplasia (FD) is a rare, non-inherited bone disorder where abnormal fibrous tissue gradually replaces healthy, structural bone. This process weakens the affected bones, making them susceptible to fracture and deformity. The condition manifests on a wide spectrum; many individuals, especially those with the monostotic form, may remain entirely asymptomatic. Whether FD qualifies as a disability rests not on the diagnosis itself, but strictly on the degree of functional impairment it causes. This impairment must result in limitations that prevent a person from maintaining regular employment.
Functional Limitations Caused by Fibrous Dysplasia
The medical foundation for a disability claim is built upon the specific, measurable ways FD interferes with daily life and physical capacity. Lesions compromise skeletal integrity, frequently resulting in pathological fractures and progressive bone deformities. Chronic pain is a common symptom, arising from the lesions, microfractures, or the aftermath of corrective orthopedic surgeries.
In the lower limbs, extensive involvement (polyostotic FD) often leads to significant mobility issues. Deformities like coxa vara or the “shepherd’s crook” deformity of the femur can cause substantial leg-length discrepancies and an altered gait. These structural changes directly restrict an individual’s ability to stand, walk, and engage in sustained physical activity, which is a major consideration in assessing work capability.
Lesions affecting the craniofacial bones introduce a different set of functional challenges. Expanding lesions in the skull base may compress cranial nerves, potentially leading to sensory impairments, such as hearing or vision loss. Furthermore, FD can be complicated by associated conditions like McCune-Albright Syndrome (MAS). MAS combines polyostotic FD with endocrine disorders, such as hyperthyroidism, increasing disease severity.
Navigating the Legal Criteria for Disability Status
Federal programs, such as those administered by the Social Security Administration (SSA), define disability based on an inability to engage in Substantial Gainful Activity (SGA). Having a diagnosis of Fibrous Dysplasia, even the polyostotic form, does not automatically meet this definition. The condition must be medically proven to prevent a person from working. The SSA uses a five-step Sequential Evaluation Process, starting with assessing current work status and the severity of the medical condition.
If the impairment is deemed severe, the SSA checks if the condition meets or equals the criteria of an impairment listed in the official “Blue Book” of medical listings. There is no specific listing for Fibrous Dysplasia or McCune-Albright Syndrome. However, a severe case may qualify under a related listing, such as a musculoskeletal disorder, if it causes a “gross anatomical deformity” of a joint with corresponding pain and loss of function. Alternatively, the endocrine complications of MAS, such as uncontrolled hyperthyroidism, might meet the criteria under the endocrine system listings.
If the impairment does not meet a listing, the process moves to a Residual Functional Capacity (RFC) assessment. This assessment determines the most an individual can still do despite their limitations, considering factors like age, education, and past work experience. If the RFC shows the person cannot return to their previous job and cannot adjust to any other type of work that exists in the national economy, they may be found disabled.
The Role of Medical Documentation in Proving Severity
Successful disability claims for FD rely heavily on comprehensive, objective medical evidence that conclusively demonstrates the severity of functional limitations. Objective evidence includes medical imaging results (X-rays, CT scans, and MRIs) documenting the location, size, and extent of the lesions. Operative reports from corrective surgeries, such as fracture fixation or osteotomy, are also necessary to establish a history of skeletal compromise.
The documentation must go beyond confirming the diagnosis; it must specifically link the FD to functional restrictions. Detailed reports from treating specialists, such as orthopedic surgeons or endocrinologists, are paramount. These reports should explicitly describe limited range of motion, the inability to bear weight for specific periods, or other measurable constraints on activity.
The documentation must also address the debilitating nature of chronic pain associated with FD. While pain is subjective, it must be supported by medical evidence, including the frequency of pain-related doctor visits and prescribed pain management treatments. The physician’s opinion on how the pain contributes to the overall functional impairment is essential. Comprehensive records detailing the disease progression and its impact on work-related tasks are the foundation for proving a disabling condition.