2nd MTP Joint Instability
2nd MTP joint instability is a condition which involves inflammation and pain located at the 2nd toe's base, level with the 2nd MTP joint, also known as the metatarsophalangeal joint.
The condition can affect the joint capsule and plantar plate structure, as well as the collateral ligaments.
The plantar plate is a thickening of the bottom surface of the joint capsule which can play a crucial role in the stability of 2nd MTP joint - it joins the base of the 2nd toe with the 2nd metatarsal. 2nd MTP joint instability can involve a gradual decrease in the stability of the 2nd MTP joint, which leads to the toe moving upwards and crossing over the big toe.
What can cause 2nd MTP joint instability?
there are many factors which can be related to 2nd mtp joint instability which include issues with the big toe like 1st MTP joint arthritis and bunions; overload or trauma of the 2nd MTP joint; and inflammatory arthritis of the 2nd MTP joint.
What are the symptoms of 2nd MTP joint instability?
The main symptoms of 2nd MTP joint instability include; pain in the ball of the foot, specifically under the base of the 2nd toe, which has been described as a similar sensation as standing on a marble; swelling around the 2nd toe joint a toe deformity such as hammer toe or crossover toe, which occurs in the more developed stages of the condition; and calluses or ulcers, which can form in several locations around the second toe joint.
In diagnosing 2nd MTP joint instability, x-rays are typically needed.A clinical examination can also demonstrate instability in the joint. Occasionally an MRI or ultrasound is useful to determine damage to the plantar plate.
Non-surgical treatment options which can be used to treat 2nd MTP joint instability include; orthotics, such as silicon toe sleeves which protect the toe from rubbing against shoes, or insoles with a dome pad that relieve some of the pressure on the mtp joint; resting, including the temporary avoidance of exercise, sports and any activities which may be aggravating the condition; modified footwear, with stiff soles that offer protection to the 2nd MTP joint and more stability; and the taping of the toe in order to realign it.
In the case of inflammation to the 2nd MTP joint, oral medications such as nonsteroidal anti-inflammatory drugs can be taken.
Surgical procedures which can be used to treat 2nd MTP joint instability include; extensor tendon lengthening, which can allow the toe to realign by loosening the tendons; MTP joint capsular release, which loosens the joint capsule and allows the toe to return to its normal position; and FDL flexor to extensor tendon transfer, also known as the Girdlestone-Taylor procedure, which releases one of several tendons that pulls the toe downwards and transfers it to the top of the toe, correcting the forces on the toe which are responsible for the condition. The second metatarsal can be shortened by performing a Weils osteotomy. Keyhole surgery can also be used to correct the condition.
As with all foot surgery it is common for swelling to persist for some months after surgery and is completely normal. This swelling will eventually completely subside with time and can take up to 12 months but often goes well before this.