Vita Yu-Hsien TU, Occupational Therapist and Project Manager
Sunshine Social Welfare Foundation
In Part 1 of our series on managing claw hand deformity of the little finger, we explored the causes and challenges associated with this common post-burn complication. We discussed how scar contracture and edema contribute to the development of claw hand deformity and emphasized the importance of addressing this issue due to its impact on hand function, particularly grip strength. In Part 2, we will delve into the various interventions used to treat claw hand deformity of the little finger. We will also outline the specific sequence of these interventions to optimize rehabilitation outcomes and restore hand functionality.
Sequence of interventions to increase MP flexion for little finger claw hand deformity
In part 1 of our series on managing claw hand deformity of the little finger, we explained that when establishing rehabilitation priorities for the management of claw hand deformity, we usually start dealing with MP joint issues first, followed by PIP joint issues. The following sequence of interventions can be followed to increase MP flexion.
1. Softening of scars and soft tissue using massage or ultrasound
Before passive stretching or active movement, massage of scars and soft tissue or ultrasound treatment can be used to soften scars and soft tissue around the MP joints, making subsequent movements smoother.
When massaging, it is usually recommended to press vertically. Do not rub, which will create excessive shearing force and cause blisters and broken skin. Press and hold in the same position for 5 to 10 seconds, then change position. Use your whole finger when pressing to increase the contact area, don't just use your fingertips. Use gentle force.
If the skin condition is suitable, ultrasound can be used on the ulnar side and back of the metacarpophalangeal joint of the little finger to promote softening deep tissue, following the general principles and precautions of ultrasound treatment.
2. MP joint traction
When joints are tightened for a long time, the space in the joint cavity will become smaller and the quantity of synovial fluid will decrease, which is not conducive to smooth joint movement. By performing joint traction to slightly separate the bones in the affected joint, it allows for synovial fluid to flow back to the joint-capsule, thus strengthening the cartilage and joint.
However, skin condition must be assessed before proceeding. Skin near the dorsal side of the PIP joint is fragile and can be easily damaged.
During traction, the therapist's hands can apply force on the left and right sides of the proximal phalanx. It’s not necessary to apply too much force, but the traction must be maintained for a while. Use a towel or anti-slip pad to cover the area before applying force. This will reduce the fatigue of the therapist's hands.
3. MP flexion stretch
Stretching can be performed by the therapist, using traction combined with stretching. Same as with traction, it’s not necessary to apply too much force, but the stretch must be maintained for a while. Stop when you stretch to the point where you feel resistance, there is no need to keep increasing the force. Stay in the stretched position for as long as possible.
It’s important to make sure that the patient feels stretched, but that it’s not overly painful. During the procedure, the patient's pain level and source of pain should be confirmed. If the patient feels some slight pain, it should be the pain from stretching, not the bone-to-bone pain in the joint. Stretching pain is acceptable, it should not be so severe that it becomes unbearable for the patient.
4. MP joints passive stretch by putty or towel
After completing the above-mentioned stretching, MP flexion should be slightly increased, or the resistance during extension stretching should be reduced. At this time, the patient can perform stretching exercises by himself. The most common way is to use putty or a towel to perform MP flexion stretching on the table. Place putty or a towel on the edge of the table to increase comfort of the fingers over the contact surface. Then, while the wrist joint of the target hand remains fixed, the patient can use his other hand to hold it so that the proximal phalanx is as perpendicular to the table as possible. The patient can then use the force of the arm to push forward to encourage MP flexion stretching, as shown in the picture below.
If MP flexion is small at the beginning, to maintain the proximal phalanx perpendicular to the tabletop, the arm posture must be adjusted. As MP flexion increases, the posture must also be adjusted, as shown in the pictures below.
During movement, the wrist is the joint that needs to be fixed, and MP joints are the main active joints. This is important to keep in mind. Grading of activity goals can be set to gradually increase the range of flexion or gradually lengthen the duration of stretching. For detailed activity design of passive flexion and extension of metacarpophalangeal joints, please refer to the course Rehabilitation of the Burned Hand - Range of Motion Evaluation and Design of ROM Rehabilitation Activities.
5. Use of dynamic cock-up splint for little finger MP joint flexion
Dynamic cock-up splint can be used to passively stretch in flexion the metacarpophalangeal joints to increase joint mobility. Note that the upper edge of the splint cannot restrict MP joint flexion. To determine the length of the outrigger, the external force of the rubber band must match MP joint flexion so that they can appear 90 degrees to each other. Therefore, when MP flexion is smaller, the length of the outrigger must be longer.
The external force applied to the joints should be low intensity for a prolonged time. Each wearing schedule should last for at least 20 to 30 minutes. If the patient cannot continue to wear the splint due to pain, first determine if the problem is with the upper edge of the splint that is restricting MP flexion, and if the problem is unbearable pain caused by excessive external force.
6. MP joints active ROM exercise
Whether you use a dynamic cock-up splint or passive stretch to carry out MP flexion, it must also be combined with active movements and activities. Perform active movements so that the increase in flexion after passive stretching can be reflected in the movement performance. The therapist fixes the patient's metacarpal bone with his hands, and then asks the patient to perform intrinsic plus movements. After flexion, stop and hold for 10 seconds. Relax and repeat. When doing active metacarpophalangeal joint flexion, it is important to fix the metacarpal bone, which can help the joint movement focus on MP flexion. If the metacarpal bones are not fixed, some joint movement will occur at the level of the CMC joint during flexion. To avoid this situation, the therapist fixes the joint with his hand. In addition, the patient can also wear a cock-up splint to perform the active movements. If it is a dynamic splint, loosen the rubber band and let the patient practice the active movement of MP flexion. Choose building blocks of appropriate size and have the patient practice picking up the building blocks by grasping them with his thumb and little finger. This can be used as an activity to practice little finger MP flexion.
Precautions
If it is the first time to perform the above-mentioned rehabilitation program, the therapist should closely observe scar tolerance. Ask the patient to observe scar condition of the area during the evening. If there are no blisters or wounds, it means that the dose and level of intensity of exercises given that day is appropriate and there are no problems.
Sequence of interventions to increase PIP extension
1. Check the skin condition on the dorsal side of PIP
Claw hand deformity of the little finger consists of a flexion contracture at the PIP site. Wounds can form easily on the dorsal side of the PIP joint, which can cause a injury to the extensor tendon. Therefore, the first step before initiating any intervention for PIP is to check the skin condition on the dorsal side of PIP joint. If there is a wound, PIP joint needs to be immobilized first. If the skin is fragile, the pressure from pressure therapy interventions needs to be reduced to avoid wounds. You can also refer to the article Pressure garments and wounds. To use or not to use? to determine whether pressure therapy should be used.
2. Management of scars on volar side of PIP joint
In the case of a flexion contracture of the PIP joint, the scar on the volar side is on a concave structure. It is recommended to use Otoform or silicone sheet to strengthen the scar control and increase the softness of the scar.
3. Splinting
Use a finger gutter to maintain PIP range of motion, wear it during the day when it does not affect activities, and wear it at night when sleeping. It is also a common way to increase PIP joint extension.
4. PIP extension stretching
As mentioned before, when stretching, we recommend long intensity-prolonged stretch. Stretch up to a range where you feel resistance and stop. There is no need to keep increasing the strength. Make sure that the patient feels stretched, but it is not too painful. However, before performing PIP extension stretching, you must rule out any injuries to the dorsal tendons that require immobilization.
Conclusion
Managing claw hand deformity of the little finger, particularly following a burn, involves a structured and patient-specific approach to restore function and prevent recurrence. Starting with interventions to increase MP flexion, including soft tissue management, joint traction, and dynamic splinting, followed by active range of motion exercises, sets the foundation for improving hand function. Additionally, addressing PIP extension with careful skin and scar management, along with proper stretching techniques, is crucial. The key to success lies in a comprehensive rehabilitation plan that combines these interventions, monitors progress closely, and adjusts as needed to ensure optimal outcomes for patients.
To learn more about rehabilitation interventions for post-burn hand deformities, check out our online course Rehabilitation of the Burned Hand - Management of Common Hand Deformities. After this course, you will be able to:
Explain the causes of various types of post-burn hand deformities.
Explain acute stage rehabilitation interventions to prevent post-burn hand deformities.
Explain rehabilitation interventions in the wound healing and rehabilitation stages to manage post-burn hand deformities.