Börje Sundell

RECOVERY OF SENSATION IN FREE FLAPS

A clinical study of touch, pain, warm and cold stimuli and two-point discrimination was performed in 27 free flaps four months to four years after the microsurgical procedure. There were 5 free skin flaps (2 with nerve suture), 15 musculocutaneous, 4 muscle-covered with split skin grafts and 3 osteomusculocutaneous flaps transplanted to various sites on the body. The results show full or nearly full recovery of touch and pain sensation in all free skin flaps. The musculocutaneous and osteomusculocutaneous free flaps developed good sensation if firmly grown onto the healthy recipient skin with normal sensation. Muscle flaps covered with split skin grafts and all flaps surrounded by scar tissue had a clinical absence of sensation. This study and our earlier findings of the regeneration of nerves in free skin grafts, in skin flaps and in experimental free flaps, lead us to suggest that the healthy denervated skin of the free flap provides a strong neurotrophic stimulus to the cut cutaneous nerves in the edges of the recipient skin. Cutaneous nerves freely regenerate in the loose subcutaneous tissue of the flap. We therefore conclude that all free flaps with skin islands have a potential for developing sufficient protective touch and pain sensation and even some superficial sensitivity.

The Return of Sensitivity to Cold, Warmth and Pain from Excessive Heat in Free Microvascular Flaps

Recovery of sensitivity to cold, warmth and pain caused by excessive heat in various types of free microvascular flaps was studied psychophysically in 27 patients who had undergone such operations four months to four years earlier. A thermal stimulator based on the Peltier principle and controlled by a microprocessor was used to measure the sensitivity to temperature in the transplants. The results were compared with the measured thresholds in the opposite sites in corresponding normal body areas. The present study showed that sensitivity to cold, warmth, and pain caused by excessive heat did return to some free microvascular flaps. According to the measurements the sensation started to return after 6 months in some flaps, and all types of thermal stimuli were felt by one patient as early as 10 months after operation. The return was more pronounced in younger people and in smaller flaps. If the hands, feet, or head defects were reconstructed with a thin skin flap (posterior aspect of thigh, dorsum of foot, or subscapular) the recovery of sensitivity was verified. Sensation returned to the musculocutaneous and osteomusculocutaneous transfers if they were on the hands or the head, or if they were sutured to healthy tissue with normal sensation. The main advantage of the psychophysical sensory testing method that we used is that it gave exact numerical data that made it possible to compare results among the different patient groups and even those obtained at different clinics and laboratories.

Latissimus Dorsi Breast Reconstruction Long Term Results and Return of Sensibility

The long-term results of 44 patients who underwent breast reconstruction after mastectomy with latissimus dorsi musculocutaneous flaps with endoprostheses were studied. Good symmetry without a brassiere was achieved in 15 patients, slight asymmetry in 24 and poor symmetry in five (11%). Symmetry when a brassiere was worn was acceptable in all but one of the patients (43/44). A third of the patients (n = 13) had developed unacceptable (grade III or IV) capsular contraction, but 39 (89%) of the patients studied were satisfied with the long-term reconstruction. Cutaneous sensibility, measured by von Freys test, had returned to 28 (64%) of the cutaneous skin islands, to their medial parts in particular. The flaps in patients who had received concentrated radiation or who had large prostheses remained numb. Sensation was normal in the scars of the donor areas in all but three patients. Latissimus dorsi breast reconstruction with an endoprosthesis is safe and simple. It gives a subjectively satisfactory result in nine out of 10 patients and is therefore a valuable method of reconstruction after mastectomy.

THE EFFECT OF PERFUSION ON POST-OPERATIVE VIABILITY IN THE REPLANTED RABBIT EAR: MEASURED BY LASER DOPPLER FLOWMETRY AND SKIN TEMPERATURE

The effect of perfusion by heparinized Ringer solution on post-operative microcirculation in rabbit ear replants was studied. One ear in each of five rabbits was replanted after perfusion with heparinized Ringer solution and these were compared with five replantations of rabbit ears without perfusion. The ears were studied post-operatively for 2 1/2 days by skin temperature monitoring and Laser Doppler Flowmetry (LDF). During the first day after replantation the perfused ears had better capillary flow, whereafter no significant differences were noted. LDF was more sensitive to changes in capillary blood flow, and this seems to make the reproducibility of LDF poor. It is, however, a suitable method for continued observation of post-operative viability.

The Late Appearance of Scars After Burns in Childhood

The late appearance of scars in children who had been burned, mainly scalded (n = 82, 90%) were analysed retrospectively from patient records and by clinical reassessment. All 91 patients who were re-examined had primarily sustained a burn of at least 5% of their total body surface area (TBSA). Only five patients showed no visible scars. The median interval between primary injury and re-examination was 17.3 years (range 6.4-30 years). Less than half of the patients (n = 36, 40%) had distinct scars without hypertrophy. The remaining 55 (60%) had either hypertrophic or constrictive scars. The scars were mostly located on the trunk (29%) and looked mainly hypertrophic (30.2%). The mean area of scars varied from 0.47% (on the neck) to 3.73% (on the left lower limb). There was no significant association between the appearance of the scar and any given method of treatment. The late cosmetic results were better than anticipated.

Microvascular Free Flaps in Early Reconstruction of Burns in the Hand and Forearm: Case Reports

In the reconstructive plastic surgery a free flap provides a one-stage method to achieve an optimal functional an aesthetic result. We report five acute burns or early contractions of the hand and forearm with free-flap reconstruction. In each case an attempt was made to design the flap to restore missing tissue components. We used three different musculocutaneous free flaps and two free skin flaps: a latissimus dorsi, a rectus abdominis and a rectus femoris renervated musculocutaneous flap, as well as a dorsalis pedis and a horizontal fasciocutaneous upper arm flap. In all five cases, the hand and wrist showed early restoration of function.

The Rabbit Ear Pedicle Flap: A New Model for Evaluating Factors Affecting the Circulation in Flaps

Laser Doppler flowmetry and transcutaneous oximetry were compared regarding their speed and accuracy in detecting occlusion of the artery of an experimental rabbit ear pedicle flap. The laser Doppler flowmeter showed a significant decrease in flow and the transcutaneous oximeter showed a significant decrease in oxygen tension within one minute after occlusion of the artery. A significant increase in flow was observed within one minute, and a significant increase in oxygen tension readings was observed one minute after the artery was opened. A steady state after opening the artery was reached sooner for the laser Doppler flowmeter readings. This study suggests that laser Doppler flowmetry and transcutaneous oximetry are equally fast and accurate in detecting changes in blood flow to a pedicle graft. These methods also have equally good reproducibility. Repeated clampings within a 30 min period did not affect the measured parameters.

Post-Anesthetic Tissue Necrosis in Experimental Pedicle Skin Flaps

Anesthetics like ether, halothane and methoxyflurane may cause side effects on the circulation of pedicle skin flaps. In patients operated under halothane anesthesia the circulatio of pedicle skin flaps was observed to be exceptionally often disturbed. The authors demonstrated in experimental pedicle skin flaps in rats, that halothane may cause larger necrotic changes than expected, especially if the flap is of unfavourable size and “critical” and subjected to bleeding.

The Repair of Severe Soft Tissue Defects of the Upper Extremity with Pedicle Flaps

Thirty-two patients with soft tissue defects of the upper extremities treated with pedicle flaps are reported. The causes of the lesions are analysed. The results are evaluated with follow-up observations and the treatment discussed.