Our Orfit blog shares information and instructions in matching our thermoplastic materials to orthotic designs.
Please check back frequently to gain inspiration and ideas in orthotic fabrication for all of your patient’s needs.
Today, we focus on the Metacarpal-Phalangeal (MCP) Joint Blocking Orthosis.
Digital blocking splints are considered restriction splints that block or restrict motion at a given joint while allowing motion at other joints.
Blocking splints are useful to redirect, isolate motion or increase active motion at joints that might have limitations due to muscle substitution, scarring, weakness, stiffness, nerve dysfunction, joint hypermobility, and/or decreased motor performance.
For example, these splints can be used to block motion at an inflammed joint in order to reduce pain and promote healing, or they might be offered as exercise splints used to redirect the force of motion to more distal or proximal joints. A digital blocking splint might be fabricated to restrict motion at the Proximal Interphalangeal Joint (PIP) in order to allow increased active motion exercises at the Distal Interphalangeal Joint (DIP) joint in patients with tightness of the joint ligaments caused by trauma or injury.
A MCP blocking splint blocks full MCP flexion, but allows active motion at the adjacent PIP and DIP joints. Active range of motion exercises while wearing this splint can help to reduce tightness of the interosseous muscles of the involved digit. An MCP blocking splint is often fabricated for patients with Stenosing Tenosynovitis or Trigger Finger. The splint allows full PIP joint and DIP joint motion while decreasing the friction between the flexor tendon and the pulley mechanism. Studies indicate that splint wear significantly reduces triggering of the flexor tendon.
- The goals of a blocking splint may be to:
- Limit motion after nerve, tendon or ligament injury or repair
- Limit motion for symptomatic and/ or pain relief
- Assist in motor re-education
- Redirect muscle force
- Assist in functional use of the hand
Patients need to be instructed whether to wear the splint full time, during functional activities or at rest.
*A digital blocking orthosis can often be fabricated circumferentially without the need for additional strapping. Patients should be able to put on and take off their splints unaided.
Many of Orfit Industries’ lightweight and thin thermoplastic materials (2.0mm 1/12” or 1.6mm 1/16”) are suitable for the fabrication of digital blocking splints. Orficast Thermoplastic Tape is an excellent material for this splint and requires very little preparation or pattern making.
To fabricate a MCP joint blocking splint, place the patient’s hand in supination. Cut a strip of Orficast and activate in hot water of minimum 65°C (149,00°F). Dry slightly to remove the excessive hot water and stretch the Orficast material. Starting at the level of the PIP joint of the involved digit, place the material over the volar digit from the PIP joint to the mid palm. Fold the material back on itself, creating a double thickness on the volar aspect.Slip the remainder of the Orficast strip dorsally around the proximal phalanx and secure to the volar portion. The MCP joint can be positioned in 0-15° degrees of flexion. Smooth all of the Orficast layers together.When sufficiently hardened, remove the splint and trim all sharp edges and corners away. The patient should be able to slide this splint on and off the involved finger, and should be able to make a fist with it on, without fully flexing the MCP joint.
Digital blocking splints can also be fabricated for the treatment of:
- Stiff joints
- Painful and inflamed joints
- Hyper mobile joints