Reverse Radial Forearm Flap to Provide Arterial Inflow to a Toe Transfer

Free neurovascular toe-(joint)-transfers compared to alternative reconstructive procedures for amputation injuries of two and tripartite fingers with substance loss

BACKGROUND

Complex injuries of the hand frequently result in loss of essential functional features. Common reconstructive procedures for soft tissue defects of the thumb or phalanges are locoregional flaps like Moberg-, Foucher-, Cross-Finger- or Littler flaps. Microneurovascular toe (joint-) transfers complete the arsenal of operative reconstructive procedures and allow for most detailed reconstructions. Our experiences with free toe transplants are reported and diversely discussed regarding contending procedures.

METHODS

From 2010 until 2019 14 patients who received emergency or elective partial or complete toe transfers were compared with a control group (n = 12) treated with contending reconstructive procedures. Aim of the reconstructions was to cover the defect with well-vascularized, sensate tissue, while preserving length and range of motion in a reliable manner.

RESULTS

The Kapandji score showed a significant difference (p- value = 0.04) with a score of 9.8 in comparison to control group (Kapandji index = 8.0).

CONCLUSION

In our heterogenic patient collective free toe transplants have proven to achieve comparable functional results for reconstruction of two and tripartite phalanxes as opposed to common local reconstructive procedures.

Versatility of the Posterior Interosseous Artery Flap: Emphasis on Powering Up the Toe Transfer

BACKGROUND

Reverse-flow posterior interosseous artery (rPIA) flap is an excellent tool for restoration of defects in the hand and upper extremity, sparing the main arteries to the hand. Its reliability has been well established.

MATERIALS AND METHODS

Fifty-one cases of rPIA flap involving 49 patients were retrospectively reviewed. The inclusion criteria were age, sex, etiology, size and location of the defect, flap size, number of perforators included, pedicle length, flap inset, donor site coverage, complications, and ancillary procedures.

RESULTS

This study included 44 men and 5 women, ranging in age between 10 and 73 years. The subjects had soft tissue defects of the hand and upper extremity mainly due to traumatic injuries, including scar contractures of the first web space in 18 cases, thumb amputations in 6 cases, and congenital defects in 1 case. Among the 51 rPIA flap elevations, 3 cases involved flap failure due to the absence of proper pedicle. A fasciocutaneous pattern was observed in 45 cases and a myocutaneous pattern in 3 cases. In 5 cases of unplantable thumb amputations, the rPIA flap was performed for arterial inflow to the secondary toe-to-thumb transfer. Venous congestion of varying degrees was noted in 7 cases involving partial necrosis in 2 cases. During the mean 17 months of follow-up, patients were generally satisfied with the final outcomes.

CONCLUSION

The rPIA flap can be used not only for soft tissue coverage of the hand and upper extremity but also as a recipient arterial pedicle for a secondary toe-to thumb transfer.

Three-Dimensional Computer-Aided Design Modeling and Printing for Accurate Toe-to-Hand Transplantation

PURPOSE

To introduce toe-to-hand transplantation performed with the assistance of both bone and soft tissue modeling using 3-dimensional printing technology.

METHODS

From May 2015 to October 2018, 31 patients (group A, 24 thumbs and 7 fingers) were included. Computed tomography scans were acquired using a spiral computed tomography scanner, and the data were processed with software. Bone, skin, and nail models were created for tailoring the flap taken from the great toe. The impact of foot pathology in terms of pain, disability, and activity restriction was assessed using the Foot Function Index. For comparison, we included 35 patients (group B) who underwent toe-to-hand transplantation without the assistance of 3-dimensional computer-aided modeling.

RESULTS

The mean duration of follow-up of groups A and B was 26 months (range, 24-31 months) and 27 months (range, 24-33 months), respectively. The mean Foot Function Index of groups A and B was 5 (range: 0-15) and 17 (range, 0-39), respectively.

CONCLUSIONS

Three-dimensional computer-aided modeling and printing provide geometric accuracy in toe-to-hand transplantation. It also may reduce the donor foot morbidity by accurate flap designing and harvesting.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.

Decellularized adipose matrix provides an inductive microenvironment for stem cells in tissue regeneration

Stem cells play a key role in tissue regeneration due to their self-renewal and multidirectional differentiation, which are continuously regulated by signals from the extracellular matrix (ECM) microenvironment. Therefore, the unique biological and physical characteristics of the ECM are important determinants of stem cell behavior. Although the acellular ECM of specific tissues and organs (such as the skin, heart, cartilage, and lung) can mimic the natural microenvironment required for stem cell differentiation, the lack of donor sources restricts their development. With the rapid development of adipose tissue engineering, decellularized adipose matrix (DAM) has attracted much attention due to its wide range of sources and good regeneration capacity. Protocols for DAM preparation involve various physical, chemical, and biological methods. Different combinations of these methods may have different impacts on the structure and composition of DAM, which in turn interfere with the growth and differentiation of stem cells. This is a narrative review about DAM. We summarize the methods for decellularizing and sterilizing adipose tissue, and the impact of these methods on the biological and physical properties of DAM. In addition, we also analyze the application of different forms of DAM with or without stem cells in tissue regeneration (such as adipose tissue), repair (such as wounds, cartilage, bone, and nerves), in vitro bionic systems, clinical trials, and other disease research.

The free neurovascular transverse wrist crease flap for repairing soft tissue defects of the fingers: clinical outcomes of multiple centers

Background

Flap transplantation is often needed for soft tissue defects of the fingers that cannot be closed directly. Sensory reconstruction of the fingers is important for patients to recover feelings. In this study, we report clinical outcomes of using free neurovascular transverse wrist crease flap for repairing finger defects from multiple centers.

Methods

This case series includes 72 consecutive patients with finger defects between June 2013 and June 2016 from multiple centers. A neurovascular transverse free radial artery superficial palmar branch flap, named transverse wrist crease flap, was designed to reconstruct soft tissue defects of the fingers with microvascular anastomosis. When there were soft tissue defects of the fingers with digital nerve defect, end-to-end neurorrhaphy between the median palmar cutaneous branch and the digital nerves was also performed. The donor incision was sutured directly. All the patients were followed-up for more than 24 months.

Results

The soft tissue defects of the fingers were all completely covered with this free neurovascular transverse wrist crease flap, and the flaps in 71 patients survived completely without ischemia. Vascular crisis appeared in one case, and the wound healed gradually after changing wound dressing for nearly 1 month. Slight infections of wounds appeared in eight cases. There were no complications in the donor site, like infection and poor wound healing. At the last follow-up, the mean static two-point discrimination was 9.6 ± 2.4 mm on the injured finger and 4.5 ± 0.8 on the contralateral corresponding finger. The motion range of the distal interphalangeal joint and proximal interphalangeal joint on the injured finger were 72.5 ± 23.3% and 78.7 ± 32.5% of the contralateral corresponding finger, respectively. Patient self-evaluations were good in 53 cases and fair in 19 cases.

Conclusions

The results indicate that the free neurovascular transverse wrist crease flap is a good choice for repairing soft tissue defects of the fingers.

Level of evidence

Therapeutic IV

Thumb Amputations in Children: Classification and Reconstruction by Microsurgical Toe Transfers

PURPOSE

Traumatic amputations of the thumb are rare in children compared with adults, but hand surgeons remain reticent to consider microsurgical reconstruction with toe-to-thumb transfers. This study reports the functional outcomes and complications of children with traumatic thumb amputations who underwent toe-to-thumb reconstruction.

METHODS

A retrospective review of children who sustained thumb amputations and whose parents elected for their child to undergo reconstruction by toe-to-thumb transfer was performed. Details of the level of thumb amputation, whether other fingers were also amputated, which toe was transferred on which vascular pedicle, survival of the transfer, and complications, were collected. Opposition, sensation, and growth of the toe-to-thumb transfers was measured. Functional and psychosocial outcomes were evaluated by both the parents and the older children using the Pediatric Outcomes Data Collection Instrument questionnaire.

RESULTS

Twenty-one thumb amputations in 19 children between the ages of 2 and 17 years were referred for secondary reconstruction. Ten were isolated thumb amputations and 11 were combined thumb and multiple finger amputations. Two children had bilateral thumb amputations. Twenty-one toe-to-thumb transfers were performed: 14 second toe transfers and 7 great toe transfers (3 great toe and 2 trimmed and 2 Morrison wraparound variations). There were no immediate postoperative reexplorations of the microsurgical anastomoses and all toe transfers survived completely. All children regained pinch and grasp function and sensation. There were no gait problems in the donor feet.

CONCLUSIONS

Microsurgical toe-to-thumb transfers should be offered as an alternative option to the traditional techniques of distraction lengthening and pollicization, for posttraumatic thumb reconstruction in children for any level of amputation from just distal to the carpometacarpal joint to the interphalangeal joint. Toe-to-thumb transfer provides length, opposition, and sensation without disturbing ambulation and is associated with excellent psychosocial outcomes as evaluated by both parents and older children.

TYPE OF STUDY/LEVEL OF EVIDENCE

Therapeutic IV.