Syphilitic arthritis is a focal form of disseminated Treponema pallidum (T. pallidum) infection with bacteria in the blood, and is associated with secondary syphilis.

Syphilitic arthritis is the result of having a disseminated T. pallidum infection. Transmission occurs most frequently after sexual contact, through minor skin or mucosal lesions. Sites of incubation are usually in the genital area, but may be in non-genital areas.

Signs and symptoms of secondary syphilis include: a generalized rash; mucous membrane lesions, with patches and ulcers; weeping pimples; generalized, non-tender, enlarged lymph nodes (lymphadenopathy); fever; and arthritis. Signs and symptoms of syphilitic arthritis may include fever; severe pain in many joints (polyarthralgias); and limited movement in one or a few swollen and tender joints. These symptoms usually appear from a few weeks up to 6 weeks after development of the chancre (see Diagnostic Code: 6310 Syphilis).

Diagnostic measures include: complete blood count (CBC); analysis and blood culture of the synovial fluid; and serologic tests for syphilis.

Treatment is started immediately for primary syphilis against the causative agent T. pallidum. It includes antibiotic therapy. The person is advised to abstain from sexual activity. Treatment for syphilic arthritis may also include: immobilization of the joint; passive range of motion (ROM) exercise; and quadriceps strengthening of the knee.

Residuals may include limitation of the joint due to destruction of the articular surfaces of the involved joint. Most persons remain in a latent phase of syphilis throughout life. The prognosis is poor for persons who develop serious late lesions of syphilis.

• The rating schedule for musculoskeletal was updated on February 7, 2021. Protection still does apply and should be considered with existing evaluations (38 CFR 3.951(a)).

• The disease must have become manifest to a degree of 10 percent or more within 1 year (for Hansen's disease (leprosy) and tuberculosis, within 3 years; multiple sclerosis, within 7 years) from the date of separation from service as specified in paragraph (a)(2) of this section. See 38 CFR 3.307(a)(3) and §3.309(a) [chronic disease].

• May be entitled to special monthly compensation where the veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• Other specified forms of arthropathy include, but are not limited to, Charcot neuropathic, hypertrophic, crystalline, and other autoimmune arthropathies.

• With the types of arthritis, diagnostic codes 5004 through 5009, rate the acute phase under diagnostic code 5002; rate any chronic residuals under diagnostic code 5003.