Introduction
Osteochondritis dissecans (OCD) is a condition that affects the ankle joint, causing pain, stiffness, and swelling. It can impact people of all ages and typically follows a twisting injury to the ankle, which can result in small fractures in the joint surface. These fractures disrupt the smooth functioning of the joint, leading to persistent discomfort if left untreated.
This guide will help you understand:
- How OCD develops
- How it causes ankle pain and instability
- The available treatment options to relieve your symptoms
Case Example: Meet Sarah, a 30-year-old avid runner who rolled her ankle while trail running. Despite some initial improvement with rest, her pain lingered, and she noticed her ankle catching during movement. An X-ray revealed a small bone fragment on her talus—a classic sign of OCD. Sarah’s story will help illustrate how OCD develops and what can be done to treat it effectively.
Anatomy: Where Does OCD Develop?
OCD commonly affects the talus, a key bone in the back of the foot that forms part of the ankle joint. The top of the talus, where the condition typically occurs, is covered by a smooth, slippery material called articular cartilage. This cartilage allows the bones to glide without friction. When a fragment of cartilage and underlying bone breaks off from the talus, it can lead to pain and instability in the ankle.
Causes: How Does OCD Develop?
Most cases of OCD result from a chip-type fracture caused by a severe ankle sprain. The location of the fracture depends on how the ankle twists during the injury.
In Sarah’s case, her ankle rolled inward, leading to a chip fracture on the inside of her talus. These fractures can vary in severity:
- If only the bone is affected, the fragment is less likely to move.
- However, if the cartilage is also damaged, the fragment may displace, making healing less likely.
If the bone fragment becomes separated from its blood supply, it may die, leading to more serious problems over time. In some cases, the initial injury may not cause a visible fracture but can damage the blood supply to the bone, leading to OCD without a clear history of trauma.
Symptoms: What Does OCD Feel Like?
Initially, OCD may mimic the symptoms of a regular ankle sprain: pain, swelling, and difficulty bearing weight. However, persistent discomfort, swelling, or a catching sensation in the ankle can signal that a chip fracture is present.
For Sarah, her pain didn’t subside after her initial ankle sprain, and over time, she experienced a catching sensation when she moved her foot. This is a common sign that the loose fragment is interfering with normal ankle movement.
Diagnosis: How Will Your Doctor Know It’s OCD?
Your doctor will review your symptoms and perform a physical exam. X-rays can reveal the presence of a chip fracture on the talus, and more advanced imaging tests such as CT scans or MRIs may be needed to understand the full extent of the damage.
In Sarah’s case, her X-ray clearly showed a loose fragment on the top of the talus, confirming the diagnosis of OCD.
Treatment: What Can Be Done for My Pain?
Nonsurgical Treatment
If OCD is diagnosed early, immobilizing the ankle in a cast or boot for six weeks may help the fracture heal. This allows the bone fragment to reattach and reduces pain. You may also need to keep weight off the ankle and use crutches during this period.
Surgical Treatment
If the fragment doesn’t heal with nonsurgical treatment or if it becomes displaced, surgery may be necessary. The goal of surgery is to remove the loose fragment and stimulate the bone to heal. This is often done by drilling small holes in the talus to encourage blood flow and the formation of new tissue.
Arthroscopic Surgery: In many cases, the procedure can be performed arthroscopically, meaning a tiny camera and instruments are inserted through small incisions to remove the fragment and drill the bone.
Open Surgery: If the fragment is located in a difficult-to-reach area, an open incision may be needed to access and repair the injury.
Rehabilitation: What to Expect After Treatment
Nonsurgical Rehabilitation
If you’re treated without surgery, your doctor will monitor your progress with regular X-rays. You’ll likely use crutches for about six weeks to keep weight off the ankle, and your physical therapist will guide you through exercises to restore strength and range of motion.
After Surgery
Following surgery, you’ll need to use crutches for four to six weeks, and your surgeon may start you on gentle motion exercises soon after the procedure. Physical therapy will help manage pain, reduce swelling, and improve ankle strength and mobility.
Sarah underwent arthroscopic surgery to remove the fragment and was able to return to light activities within six weeks. With the help of physical therapy, she regained her ankle strength and eventually returned to running without pain.