Rheumatologic Disorders

Rheumatologic Disorders

Matthew J. Anderson

Stefanos Haddad

Hollie Garber


Rheumatologic conditions have a varied effect on the foot. Many will cause serious morbidity and disability associated with foot pain and instability. The main goal for the foot, as with all rheumatologic conditions, is early detection and pharmacologic treatment of the underlying disease to prevent long-term sequelae. Once pathology is manifest within the joint or soft tissues of the foot, treatment modalities progress and ultimately surgery to restore pain-free ambulation.


Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by synovitis, periarticular bone loss, and osteoporosis. The disease affects between 0.3% and 2.1% of the general population1 and is 2 to 4 times more common in women than in men.2 The disease prevalence peaks in the third to fifth decades and follows 1 of 3 pathways: (1) a relentless, destructive, and aggressive course; (2) a monocyclic course notable for a single episode of synovitis without permanent cartilage damage; and (3) a polycyclic course with multiple episodes of attack followed by remissions, which is the most common.

The disease can affect all joints of the body but preferentially affects the small joints of the hand and foot. Foot and ankle symptoms account for 50% of the presenting complaints at diagnosis, and it is estimated that 85% to 90% of patients with RA will experience foot or ankle problems3 with increasing incidence over the duration of the disease process.4

Initial complaints with rheumatoid arthritis involve vague forefoot pain and metatarsalgia resulting from synovitis and intra-articular effusion, a variable waxing and waning course of foot swelling, pain with ambulation, and tenderness to palpation. The course of rheumatoid arthritis can be broken up into 4 stages based on physical examination and radiographic findings:

  • Stage I: Discomfort and synovitis; no bone deformity or significant joint space narrowing

  • Stage II: Early involvement with flexible deformity; minimal erosive changes

  • Stage III: Fixed soft tissue deformity; significant erosive joint changes (Figure 13.1)

  • Stage IV: Severe hallux valgus, dislocation of the lesser metatarsophalangeal (MTP) joints with fixed hammer toe or claw toe deformities, pes planovalgus (flatfoot), and hindfoot arthroses; articular destruction (Figure 13.2)

The characteristic x-ray findings of RA are similar for all synovial joints. Early examination reveals soft tissue swelling and diffuse juxta-articular osteoporosis.5 Continued bouts of synovial inflammation lead to marginal cortical erosions,6 eventually giving to central erosions, joint space narrowing, and subluxation or dislocation. Radiologic progression correlates to the number of macrophages lining the joint and activate osteoclasts and other inflammatory cells.7 These cells release the inflammatory
cytokines and proteinases resulting in joint destruction.

Diagnosis of RA is based on clinical, radiographic, and laboratory findings (Table 13.1). The American College of Rheumatology recommends that at least 4 of the 7 criteria be present to make the diagnosis of RA.8 Serologic testing for rheumatoid factor is present in 70% to 90% of cases of RA, but may be elevated in numerous inflammatory conditions and other diseases.

Rheumatoid arthritis manifestations in the forefoot begin with inflammation in the synovium resulting in joint effusions. Significant joint effusions destabilize the capsular structures and collateral ligaments and with continued ambulation results in subluxation and eventual dislocation occur.4,9 The proximal phalanx displaces proximally and dorsally; the long flexor tendons and intrinsic muscles contract locking the proximal phalanx behind the metatarsal neck and generating a downward force on the metatarsal head. The dislocation of the lesser toes creates imbalances in the intrinsic and extrinsic muscles resulting in progressive claw toe deformity (Figure 13.3). With the lesser toes significantly clawed, the hallux loses lateral stability and migrates laterally to position below the second and third toes. As the hallux valgus deformity worsens, the weight-bearing of the first ray decreases with increasing force through the second and third metatarsal heads.

Midfoot pathology begins with synovitis and chondrolysis of the tarsometatarsal joints (Figure 13.4). The flattening of the midfoot is multifactorial with links to arthritis, ligamentous laxity, and posterior tibial tendon rupture.10,11 The pes planus foot typically continues to have limited motion producing a fibrous or boney ankyloses. Occasionally, the MTC joint becomes hypermobile which can result in transfer metatarsalgia and make weight-bearing difficult.

Hindfoot pathology is a less common finding associated with rheumatoid arthritis,
involved 10 times less frequent than the forefoot.12 Changes to the hindfoot occur later or slower as there is a significant increase in percentage of patients with symptomatic hindfoot arthrosis among patients diagnosed with RA for more than 5 years.9 Similar to other joints the pathology of RA in the hindfoot begins with destruction of the capsule and surrounding ligaments destabilizing the joint, beginning with the subtalar joint. The progression of RA to the pes planovalgus deformity and subtalar destruction can result in the difficult situation of pantalar arthritis and instability.

Sep 8, 2022 | Posted by in ORTHOPEDIC | Comments Off on Rheumatologic Disorders

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