Current And Emerging Techniques For Hallux Rigidus
Given the relatively common nature of hallux rigidus, this author offers insights from the literature on current modalities as well as emerging surgical advances.
Hallux rigidus is a very common disorder affecting the first metatarsophalangeal joint. Hallux rigidus is characterized by arthritic changes of the joint resulting in osteophyte formation, limitation in joint range of motion and painful ambulation. It tends to affect men more frequently than women and reportedly affects 10 percent of people 20 to 34 years of age and 44 percent of people over 80 years of age.1
Researchers have found a greater negative impact on health status among patients with hallux rigidus in comparison to those with hallux valgus.2 This would certainly correspond with what one frequently sees in clinical practice where many patients with hallux valgus report few or no symptomatic problems related to the deformity. Alternately, a majority of individuals with hallux rigidus present with a complaint of joint pain or compensatory gait issues resulting in lateral foot pain, lower leg, lateral knee, hip or back pain.3,4
While the exact cause of hallux rigidus is not completely understood, there are a number of factors that appear to result in the development of this joint deformity. It is likely a combination of structural and biomechanical influences that result in an alteration of normal joint kinematics and the subsequent development of osteoarthritis.
The cause of hallux rigidus is multifactorial. A common cause is pes planovalgus in which there is a hypermobility of the first ray resulting in transverse and frontal plane motion of the first metatarsal and subsequent trauma to the joint resulting in joint cartilage erosion and osteophyte formation.5 Other factors include an elongated first metatarsal, a metatarsus primus elevatus, trauma to the first MPJ, post-surgical complications from procedures for hallux valgus in which preexisting osteoarthritis existed, osteochondral fractures of the first MPJ and a squared first metatarsal head.6,7
Clinical examination of the first MPJ will reveal an enlargement of the joint with localized erythema and edema. Upon palpation to the margins of the joint, one can feel osteophyte formation around the first metatarsal head and the base of the proximal phalanx dorsally. Dorsiflexion is restricted and often as the condition progresses, the hallux will maintain an equinus position. Joint range of motion is restricted with limitation of dorsiflexion, the primary factor in the ambulatory pain. Patients will also notice a lack of flexion of the great toe due to osteoarthritic changes that occur within the sesamoid complex. Joint range of motion can often be painful, particularly end arc range of motion at the end of dorsiflexion.
A weightbearing examination will often demonstrate a hallux that is sitting in a slight varus orientation as the individual attempts to flex the great toe against the ground in order to stabilize it. Gait examination will often demonstrate an antalgic gait with lateralization due to a lack of dorsiflexion or pain within the joint.
Pertinent Insights On The Diagnostic Workup
Plain film radiographs are essentially all that is necessary when diagnosing hallux rigidus. One will note joint space narrowing, joint space irregularity, subchondral sclerosis, marginal osteophyte formation and osteophyte formation around the margins of the sesamoid bones. Often, a loose body is present in the dorsal aspect of the joint as the osteophyte on the dorsal aspect of the base of the proximal phalanx fractures away. On the lateral projection, one may note a metatarsus primus elevatus. On an AP view, clinicians may often recognize a long first metatarsal with a squared-off metatarsal head.