Complex Regional Pain Syndrome Type 1 (Reflex Sympathetic Dystrophy) Clinical Presentation

Updated: Mar 09, 2021
  • Author: T P Sudha Rao, MD; Chief Editor: Herbert S Diamond, MD  more...
  • Print


The three clinical stages of type 1 complex regional pain syndrome (CRPS 1) are acute, subacute, and chronic. The acute form lasts approximately 3 months. Pain, often burning in nature, is one of the first symptoms that initially limits function. Swelling, redness with vasomotor instability that worsens with dependency, hyperhidrosis, and coolness to the touch are common physical findings. Demineralization of the underlying bony skeleton begins because of disuse.

If the process is not arrested or reversed in the acute phase, the condition may progress to the subacute stage, which can last for up to 9 months. The patient develops persistent severe pain in the extremity and fixed edema that would have been reversible with elevation during the acute phase. The redness of the acute stage gives way to cyanosis or pallor and hyperhidrosis to dry skin. Loss of function progresses, both because of increased pain and fibrosis of the joints caused by chronic inflammation. In the hand, this leads to flexion deformity of the fingers. The skin and subcutaneous tissues begin to atrophy. Demineralization of the underlying bony skeleton becomes pronounced.

If the process continues, the chronic phase may develop approximately 1 year after disease onset. This stage may last for many years or can be permanent. Pain is more variable during this period. It may continue undiminished or abate. Edema tends to subside over time, leaving fibrosis around the involved joints. The skin is dry, pale, cool, and shiny. Flexion and extension creases are absent. Loss of function and stiffness are marked, and osteoporosis is extreme. In the upper extremity, this can manifest as a frozen shoulder and claw hand.

A thorough general history is strongly suggested. Maintaining a high index of suspicion is important because proper treatment requires rapid diagnosis and prompt therapy.

CRPS 1 commonly involves only one extremity. It is bilateral in approximately 25% of cases, but in those cases it is usually more prominent on one side.

Pain in CRPS 1 has the following characteristics:

  • Usually constant and disproportionate to the precipitant injury
  • May be exacerbated by ambient factors such as loud noises and emotional factors (eg, stress, light touch, active motion, passive motion)
  • May be described as burning, cutting, searing, pressure, or tearing
  • Usually begins locally but may progress to involve the entire extremity

Possible evidence of prior increased sympathetic activity includes the following:

  • Hyperhidrosis
  • Cold hands
  • Fainting

Precipitating factors may include any of the following:

  • Prior trauma, which may be trivial (eg, venipuncture) or significant (eg, Colles fracture), with or without diagnosable nerve injury
  • Prior surgery
  • Recent limb immobilization due to hemiplegic stroke, myocardial infarction
  • Systemic disease such as diabetes

Physical Examination

Perform a thorough physical examination followed by a focused examination of the involved extremity. Patients with CRPS 1 may present with suggestive physical findings that point to a presumptive diagnosis (eg, edema, stiffness, discoloration, abnormal skin moisture, tenderness).

Edema is the most consistent physical finding and is always disproportionate to the severity of the precipitant injury or event. Pain, swelling, and color change may be more prominent with dependency in the early stages. Edema worsens rather than improves and extends beyond the region of initial concern. It evolves into a brawny, nonpitting edema that may progress to an intense fibrosis in all the joints of the extremity.

Stiffness is more severe than expected and may be very distressing to the patient.

Discoloration varies depending on the stage of disease. It may be dusky, cyanotic, pale, or red and may eventually lead to skin hypopigmentation. In the hand, discoloration begins as redness over the metacarpophalangeal (MCP) or proximal interphalangeal (PIP) joint flexion creases early in the disease and progresses as a streak across the palm.

Early in the course of CRPS 1, abnormal skin moisture consists of hyperhidrosis. Late in the course, it consists of dry skin.

Tenderness is initially localized but may progress to generalized tenderness. Exquisite tenderness, both periarticular and interarticular, is often present. Patients may exhibit allodynia (ie, pain with nonnoxious stimuli) and hyperpathia (ie, persistent pain after light pressure).

Other physical findings may include the following:

  • Atrophy of the skin and subcutaneous fat pads
  • Fibrosis of the palmar fascia
  • Absence of extensor and flexor creases over joints
  • Frozen shoulder, flexion deformities of the fingers, claw hand