What Is Ribbing Disease?

Ribbing disease is a rare disorder that causes bony growths to develop on the long bones of the legs—the thigh bone and shin bone. The condition can also affect the long bones of the arms. Ribbing disease often develops after puberty (after the skeleton has matured) and will affect more women than men.

Ribbing disease goes by other names, including multiple diaphyseal sclerosis, diaphyseal sclerosis, and heredity multiple diaphyseal sclerosis. It is also is a part of a group of disorders called sclerosing bone dysplasias—rare genetic diseases characterized by abnormally thick and overgrown bones.

These disorders are usually caused by defects in the osteoclast regulation process (replacement of old bone with new bone), leading to abnormal accumulation of bone.

Here is what you need to know about Ribbing disease, including signs and symptoms, causes, diagnosis, and treatment.

Ribbing Disease Symptoms

The most common signs and symptoms of Ribbing disease include pain and muscle weakness in the areas of the body where bone growths have developed. These bone growths can occur in the bones on one side of the body or in different bones on both sides of the body.

Most people with Ribbing disease will present to their healthcare providers with pain that has no known cause. The pain will be localized and sporadic, and there might be tenderness in the legs or thighs.

Ribbing disease does not cause all-over pain or inflammation because it is not a systemic disease—a disease that affects other parts of the body or the whole body. Most people with Ribbing disease are considered healthy and will not have neurological and gait (walking) abnormalities or severe pain.

Ribbing disease shares similar symptoms to a disease called Camurati-Engelmann disease (CED), which typically begins in childhood. CED also affects more bones on both sides of the body.

Causes

An exact cause of Ribbing disease is unknown, but researchers think it is caused by genetic changes in the transforming growth factor beta-1 (TGFB1) gene. This gene provides instructions for producing a TGFB1 protein.

TGFB1 protein triggers chemical signals to regulate cell activities, including those responsible for the growth of cells, cell movement, cell function, and controlled cell death.

Researchers also think Ribbing disease is inherited in an autosomal recessive manner. For someone to develop an autosomal recessive disorder, they have to inherit two mutated genes, one from each parent.

If you are born to parents who have the same autosomal recessive gene, you have a 1 in 4 chance of inheriting the abnormal gene from both parents and developing an autosomal recessive disorder.

Diagnosis

The limited literature on Ribbing disease leaves researchers to speculate there have only been 20 to 30 cases reported.

Because it is rare and a lot of healthcare providers don’t know much about it, diagnosis is often delayed and confused with other sclerosing bone dysplasias, metabolic diseases (genetic conditions that cause metabolism problems), or osteomyelitis (infection of the bone).

A diagnosis of Ribbing disease can be made after reviewing clinical history, bloodwork, and imaging, and ruling out other conditions. For your clinical history, your healthcare provider will want to know what symptoms you are experiencing, including bone pain and muscle weakness, and the location of the pain. 

Bloodwork for most people with Ribbing disease will be normal. Normal bloodwork rules out inflammatory diseases.

Imaging

Your healthcare provider can confirm Ribbing disease by requesting imaging studies to look for bone changes. This may include computerized tomography (CT) scans, magnetic resonance imaging (MRI), and bone scans.

With Ribbing disease, imaging will show increased bone density (sclerosis), endosteal (endosteum), and periosteal (periosteum) thickening and narrowing of the intramedullary canal (inside of the bone). The endosteum lines the inner surface of the medullary cavity of the long bones while the periosteum covers the outer surface of bones.

Treatment

Treatment options for Ribbing disease may include medications, such as non-steroidal anti-inflammatory drugs (NSAIDs), bisphosphonates, and corticosteroids. If medications do not help manage pain and other symptoms, your healthcare provider might recommend a surgical procedure called intramedullary reaming.

Intramedullary reaming involves stabilizing long bones through reaming (widening) of the medullary cavity and inserting an intramedullary nail, with or without locking bolts. Reaming of affected long bones allows for improved mobilization especially in people who need surgical debridement of bone tissue.

A 2013 report in the Spanish Journal of Orthopaedics Surgery and Traumatology reports that pain improves immediately after surgery with patients being asymptomatic up to a year later. Unfortunately, there is not a lot of data on long-term follow-up after intramedullary reaming for Ribbing disease.

A Word From Verywell

Ribbing disease is an extremely rare disease that is believed to be self-limiting, although there is not a lot of information about progression and effective treatments. Fortunately, healthcare providers are learning more about it every day and they are able to make a diagnosis based on symptom history and imaging.

If you or a child experience long bone pain or muscle weakness in the legs or arms, it is a good idea to get these symptoms checked out. Your healthcare provider is in the best position to make a diagnosis and recommend treatment options.