(1)
Yotsuya Medical Cube, Chiyoda-ku, Tokyo, Japan
Basic Principles
When treating adduction contracture of the thumb, after cutting the adductor muscle and widening the first web space, there is a need to cover the skin defect area with a skin flap. Although there are reports of inserting abdominal flaps or reverse flow forearm flaps, this can cause dome like deformity and an aesthetic reconstruction is difficult.
With the skin flap reported by Spinner that is created from the radial side of the index finger, there is no need to include major arteries and it is possible to create a comparatively large flap with a very pleasing outcome aesthetically.
The flaps created in this section can be used either as a rotation flap or a sliding flap.
Selectable Flaps and Surgical Procedures
Spinner flap4 & 5 Z plastyReverse flow radial forearm flapPedicled abdominal flapFree abdominal perforator flapFree groin flapThe difficulty level of each surgical procedure is shown subsequent to the procedure title (e.g., Level of Difficulty: 2). The levels range from 1 to 5, with level 1 indicating a preliminary level and level 5 indicating a very advanced level.
6.1 Spinner Flap (Level of Difficulty: 1)
Information
Vascular pedicle No specific arteries are included
Size It is created in the middle of the radial index finger, however when creating skin flaps exceeding a width of 20 mm, it is necessary to conduct a skin graft as reefing is difficult. The tip of the flap can extend as far as the PIP joint.
Advantage First choice surgical procedure for treating adduction contracture of the thumb. Simple with stable blood flow. Specific arteries are not included, however there is no problem even if the width to length ratio exceeds 1:3. Apart from use for the first interdigital area, can also be rotated and transferred to the base of the thumb.
Disadvantage In cases where large soft tissue is required, a skin graft is required for the donor site which can become somewhat obvious.
6.1.1 Operation Procedures
Fig. 6.1
Procedure 1: A burn scar is present on the first interdigital area, and a localized flap surgery (4 Z plasty) was conducted, but there was no improvement due to an implicit lack of skin
Fig. 6.2
Procedure 2: An incision is made in the first interdigital area, the subcutaneous fibrous cord is resected and the adduction contracture of the thumb released
Fig. 6.3
Procedure 3: The flap is designed in the middle of the radial side of the index finger
Fig. 6.4
Procedure 4: The flap is dissected above the fascia, but the palmar/dorsal digital arteries/veins are not included in the flap. The flap is dissected to the deep first web space area, and in cases where there is contracture of the adductor pollicis muscle, the required muscle is cut. The palmar side of the index finger is detached subcutaneously to make it easier to close the donor site
Fig. 6.5
Procedure 5: The flap is transferred and the donor site closed. A skin graft is conducted if there is considerable tension
Fig. 6.6
Procedure 6: The flap is pulled deeply into the web space and sutured
Fig. 6.7
Procedure 7: In cases with severe adduction contracture of the thumb, the patient is Procedure made to wear a night brace for several months to prevent recurrence
6.2 4 & 5 Z plasty (Level of Difficulty: 2)
Information
Vascular pedicle Subcutaneous vascular plexus
Size When creating for the first interdigital space, the standard is 2–3 cm per side, and a 60°Z plasty. A small Z plasty is not very effective.
Caution A 4-Z plasty has a considerable extension effect. For a 5 -Z plasty, part of the flap requires trimming.