Chapter 2: Cold Therapy Modalities

INTRODUCTION

The use of cold as a therapeutic agent has a long history, beginning in Egypt around 2500 bc.¹ Cold has had many different uses since that time with application for injury management and rehabilitation becoming prevalent in the 1950s and 1960s.^2-4 Although many technological advances have been made in the realm of therapeutic modalities in the past century, the use of cold (water, ice, or gel) remains one of the most effective and least expensive treatment choices for acute injury and pain management.

Cryotherapy, defined as the use of cold modalities for therapeutic purposes, is used as a first-aid measure after trauma and as a supplemental tool in the rehabilitation of musculoskeletal and neuromuscular dysfunctions. The basis for cryotherapy is grounded in the physiological responses that occur when tissue temperature is lowered. Cold decreases blood flow and tissue metabolism, minimizing bleeding and acute inflammation immediately or soon after injury or surgery.^5,6 Muscle spasms and tightness from myofascial trigger points can be diminished, allowing for greater ease of motion. Cold can elevate a patient’s pain threshold, facilitating ease of exercises with less discomfort.

Cold can be easily applied in different ways, including cold packs, ice massage, cool baths, cold compression devices, hypercooled air, or vapocoolant sprays. Caution should be taken, however, to avoid undue exposure to cold in persons with conditions such as cold hypersensitivity, impaired circulation, diminished sensation, or hypertension. This chapter includes descriptions of the physical principles, biophysical responses, and clinical applications of cold therapy modalities.

PHYSICAL PRINCIPLES

Cooling is achieved by removing or abstracting heat from an object and not by adding cold. When a therapeutic cooling agent is applied, the temperature of the skin and underlying tissues is lowered by removing heat from the body (Fig. 2-1). The principal modes of energy transfer used for therapeutic cooling include conduction, convection, and evaporation (Table 2-1).

Conduction

Conduction is the transfer of heat by direct interaction of the molecules in the warmer area with those in the cooler area.⁷ Warmer, rapidly moving particles transfer or exchange heat to cooler, slower-moving particles that are in close proximity. The most commonly used conductive cooling methods in rehabilitation include placement ...