Latissimus dorsi flap coverage of soft tissue defect following below-knee amputation: emphasis on flap design and recipient vessels

Reconstruction of soft tissue defect around knee with thoracodorsal artery perforator flap and muscle-sparing latissimus dorsi flap

INTRODUCTION

Around the knee reconstruction is challenging for reconstructive surgeons. Several methods have been proposed, including perforator and muscle flaps; however, all have advantages and disadvantages. As the success rate of free-flap surgery increases, reconstruction around the knee using this method is becoming increasingly popular. Nevertheless, there are no large-scale case reports in the previous literature using either a thoracodorsal artery perforator flap (latissimus dorsi (LD) perforator flap) or a muscle-sparing latissimus dorsi (msLD) flap for reconstruction around the knee. In this retrospective report, we describe our clinical experiences and present an algorithm regarding recipient vessel choice in free-flap reconstructive surgery of around the knee defects.

PATIENT AND METHODS

Fifty-six cases in which a flap from the lateral thoracic area was used to reconstruct an around the knee defect between January 2016 and March 2022 were reviewed. The patients were aged 18-87 years (mean, 52.13 years), and of the 56 patients, 36 were male and 20 were female. Injuries were caused by trauma, contracture, rheumatoid vasculitis, tumor, infection, burns, sunken deformity, and pressure sores. The 56 cases included 22 with a defect including the knee, 14 with a defect below the knee (7 of the primary below-knee amputation [BKA] and 7 of the secondary BKA), 9 involving the distal medial thigh, 8 involving the distal lateral thigh, 2 involving the popliteal area, and 1 involving the middle thigh. Most cases were reconstructed using a single LD perforator flap or msLD flap. Chimeric or supplementary flaps were used when extensive coverage or dead space obliteration was required. The average size of the defect area was 253.6 cm2 (range: 5 × 6-21 × 39 cm2 ).

RESULTS

In the cases, the recipient artery used included the following: descending genicular artery (23), superficial femoral artery (14), descending branch of the lateral circumflex femoral artery (14), anterior tibial artery (2), popliteal artery (2), and posterior tibial artery (1). The recipient vein included the greater saphenous vein (24), descending branch of the lateral circumflex femoral vein (14), superficial femoral vein (7), descending genicular vein (6), anterior tibial vein (2), popliteal vein (2), and posterior tibial vein (1). The average flap size was 281.8 cm2 (range: 4 × 8-35 × 19 cm2 ). All flaps survived; however, seven complications occurred, including 2 partial flap losses, 1 arterial insufficiency, 1 hematoma, 1 minor dehiscence, 1 donor-site graft loss, and 1 short BKA. Normal knee range of motion (121-140°) was observed in 34 patients and 16 showed varying degrees of limited range of motion. Motion was not observed in four patients who underwent knee fusion and could not be evaluated in two patients who underwent above-knee amputation. The mean follow-up duration was 24.6 months (range: 4-72 months).

CONCLUSION

The LD perforator flap is ideal for the reconstruction of around the knee defects because it enables a long pedicle, large flap, and chimeric design. The msLD flap is ideal because it enables strong stump support, dead-space obliteration, and infection control. Moreover, since the two flaps are distant from the knee, this method is advantageous in terms of postoperative rehabilitation and there is minimal donor-site morbidity due to the thin nature of the LD muscle. In addition, the flap can be elevated in three positions and the operation can be completed without positional changes in various recipient vessel locations. Based on our experience, we conclude that the LD flap has the potential to be used as widely as or in preference to the anterolateral thigh flap in the reconstruction of around the knee defects.

A Modified Scapular-Parascapular Flap Design for Optimal Coverage of the Residual Limb

BACKGROUND

Large soft tissue defects associated with major limb amputation pose a challenge to the reconstructive surgeon due to the 3-dimensional contour of the residual limb and the need to withstand the unnatural shear forces imparted by prosthetic sockets. Fasciocutaneous flaps based on the circumflex scapular system have proven useful for residual limb coverage due to the durability of the tissue provided, the absence of functional morbidity, and the ease of reelevation. A modified, bilobed flap design that incorporates large Burrow triangles into each limb serves to leverage the perforasome anatomy of the posterior trunk to provide maximal 3-dimensional coverage and favorable flap geometry while also facilitating donor site closure.

METHODS

A retrospective medical record review was performed for all patients who underwent reconstruction of a residual limb after major amputation using the modified, bilobed scapular-parascapular free flap design at Walter Reed National Military Medical Center between 2018 and 2021. A computer-based application was used to calculate flap area and dimensions based on photographs of preoperative and intraoperative markings.

RESULTS

Six patients with varying amputation levels (2 transtibial, 1 transfemoral, 1 hip-disarticulation, 1 hemipelvectomy, 1 transradial) underwent soft tissue coverage using the modified flap design. Mean flap area was 318.4 cm 2 with 51.1 cm 2 attributable to the modified design. This represents a 16% increase over a conventional bilobed design. There were no partial or complete flap failures.

CONCLUSIONS

The modified scapular-parascapular flap design enables harvest of a larger and more versatile fasciocutaneous flap with geometry that is well suited for coverage of the residual limb.

Clinical Application of Artificial Dermis and Autologous Skin in Repairing Skin and Soft Tissue Defects of Hands and Feet with Bone Exposure Injuries

Patients with skin and soft tissue defects are very common. Mild trauma often causes mild skin damage, while severe injuries are often accompanied by bone and tendon exposure, which brings great pain to patients. For the defect of skin and soft tissue, the traditional treatment methods are mostly medium or full-thickness skin or skin flap transplantation. These methods are effective in wound repair, but there are still many problems. In recent years, with the improvement of tissue engineering technology, the use of artificial skin to repair various skin wounds is gradually becoming clinical, and the key technology of skin tissue engineering lies in the development of dermal substitutes. The appearance of artificial dermis not only solves the shortage of autologous skin source but also makes the operation simple and easy. The purpose of this study was to investigate the clinical effect of artificial dermis combined with autologous skin grafts in repairing hand and foot skin and soft tissue defects with bone exposure. The results show that the use of artificial dermis combined with autogenous blade thick skin to treat patients with hand and foot soft tissue injury with bone exposure has a good clinical effect, and the skin is alive and has fewer complications, which is worthy of promotion.

Secondary Reconstruction of Frontal Sinus Fracture

Fractures of frontal sinus account for 5%-12% of all fractures of facial skeleton. Inadequately treated frontal sinus injuries may result in malposition of sinus structures, as well as subsequent distortion of the overlying soft tissue. Such inappropriate treatment can result in aesthetic complaints (contour deformity) as well as medical complications (recurrent sinusitis, mucocele or mucopyocele, osteomyelitis of the frontal bone, meningitis, encephalitis, brain abscess or thrombosis of the cavernous sinus) with potentially fatal outcomes. Frontal contour deformity warrants surgical intervention. Although deformities should be corrected by the deficiency in tissue type, skin and soft tissue correction is considered better choice than bone surgery because of minimal invasiveness. Development of infection in the postoperative period requires all secondary operations to be delayed, pending the resolution of infectious symptoms. The anterior cranial fossa must be isolated from the nasal cavity to prevent infectious complications. Because most of the complications are related to infection, frontal sinus fractures require extensive surgical debridement and adequate restructuring of the anatomy. The authors suggest surgeons to be familiar with various methods of treatment available in the prevention and management of complications following frontal sinus fractures, which is helpful in making the proper decision for secondary frontal sinus fracture surgery.

Application of the orthoplastic reconstructive ladder to preserve lower extremity amputation length

BACKGROUND

A primary goal in traumatic lower extremity amputation management is preservation of limb length. Energy expenditure during ambulation directly correlates with residual limb length, preserved limb segments, and stable joint preservation. An additional factor affecting limb function includes achieving adequate residual limb soft tissue coverage. This report describes techniques for achieving a stable soft tissue envelope to facilitate limb length and joint preservation.

METHODS

A series of traumatic amputation cases with inadequate soft tissue coverage are reviewed. Concepts from the reconstructive surgery ladder were used to achieve residual limb soft tissue coverage and to preserve lower extremity amputation length.

RESULTS

Soft tissue coverage was accomplished through a series of methods including delayed primary closure with assistance from an external tissue expander, use of acellular dermal regenerative templates combined with split-thickness skin grafting and negative-pressure wound therapy, use of biologic scaffolds such as extracellular porcine urinary bladder matrix combined with delayed skin grafting, and local pedicle flaps or adjacent tissue rearrangements and free tissue transfers.

CONCLUSIONS

The preservation of residual limb length in lower extremity amputations is crucial to optimize prosthetic fitting and to obtain the maximal functional outcome. A series of cases are presented that outline soft tissue coverage options for preserving maximal residual limb length. Applying various concepts from the reconstructive ladder may allow for viable soft tissue coverage to maximize functional outcome.

Reverse Anterolateral Thigh Flap to Revise a Below-knee Amputation Stump at the Mid-tibial Level

Summary:

The reconstruction of defects around the knee often poses a challenge due to the limited availability of local soft tissues. Indeed, this same problem is encountered when attempting to revise a below-knee amputation stump. Moreover, due to a paucity of recipient vessels in those who have undergone previous amputation secondary to trauma, free-flap reconstruction is often challenging and not always successful. We report a case of a reverse anterolateral thigh (ALT) flap used to revise a long below-knee amputation stump. Previous reports in the literature attest to the versatility of the reverse ALT to cover defects around the knee and proximal tibia, but to our knowledge, this is the first report of a reverse ALT reaching to the mid-tibial level.