Outcomes in microsurgery

The role of patient-reported outcomes in peripheral nerve surgery

Measuring the outcome of peripheral nerve surgery is challenging because of the spectrum of functional impairment is dependent on the level and severity of the lesion. There are no nerve-specific patient-reported outcome measures, and no universally accepted outcome measurement both in terms of the parameters to be assessed and the methods and timing of the assessment. Nevertheless, the use of patient-reported outcome measures is fundamental to better understand the needs and expectations of patients, to take advantage of all treatment opportunities to offer the best possible support to these patients. This paper outlines current concepts in the measurement of outcome in peripheral nerve surgery.

A Systematic Review of Microsurgical Pedicle Lengthening in Free Tissue Transfer

INTRODUCTION

Traumatic injuries that require free tissue flaps for reconstruction may require vascular pedicle extension between the flap and recipient vessels to form a clear anastomosis. Currently, a variety of techniques are used, each with their own potential benefits and harms. In addition, reports in the literature conflict on the reliability of pedicle extensions of vessels in free flap (FF) surgery. The objective of this study is to systematically assess the available literature about outcomes of pedicle extensions in FF reconstruction.

METHODS

A comprehensive search was performed for relevant studies published up to January 2020. Study quality was assessed using the Cochrane Collaboration risk of bias assessment tool and a set of predetermined parameters was extracted by 2 investigators independently for further analysis. The literature review yielded 49 studies investigating pedicled extension of FF. Studies meeting inclusion criteria underwent data extraction focusing on demographics, conduit type, microsurgical technique, and postoperative outcomes.

RESULTS

The search yielded 22 retrospective studies totaling 855 procedures from 2007 to 2018 in which 159 complications (17.1%) were reported in patients aged between 39 and 78 years. Overall heterogeneity of articles included in this study was high. Free flap failure and thrombosis were the 2 most prevalent major complications noted: vein graft extension technique had the highest rate of flap failure (11%) in comparison with the arterial graft (9%) and arteriovenous loops (8%). Arteriovenous loops had a rate of thrombosis of 5% versus 6% in arterial grafts and 8% in venous grafts. Bone flaps maintained the highest overall complication rates per tissue type at 21%. The overall success rate of pedicle extensions in FFs was 91%. Arteriovenous loop extension resulted in a 63% decrease in the odds of vascular thrombosis and a 27% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05). Arterial graft extension resulted in a 25% decrease in the odds of venous thrombosis and a 19% decrease in the odds of FF failure when compared with venous graft extensions (P < 0.05).

CONCLUSIONS

This systematic review strongly suggests that pedicle extensions of the FF in a high-risk complex setting are a practical and effective option. There may be a benefit to using arterial versus venous conduits, although further examination is warranted given the small number of reconstructions reported in the literature.

How to measure success in lower extremity reconstruction, which outcome measurements do we use a systematic review and metanalysis

Different factors have to be considered and weighted in the treatment algorithm of lower extremity reconstruction. A combination of both clinicians' and patients' perspectives is necessary to provide a conclusive picture. Currently, there aren't any standardized and validated measurement data sets for lower extremity reconstructions. This makes it necessary to identify the relevant domains. We, therefore, performed a systematic review and metanalysis of outcome measurements and evaluated their ability to measure outcomes after lower extremity reconstruction. A systematic review and metanalysis according to the 'Preferred Reporting Items for Systematic Reviews and Meta-Analyses' protocol were performed for studies reporting at least one structured outcome measurement of lower extremity reconstruction. Both Patient (PROMs)- and Clinician reported outcome measurements (CROMs)were analyzed. Of the 2827 identified articles, 102 were included in the final analysis. In total 86 outcome measurements were identified, 34 CROMs, 44 PROMs and 8 (9.3%) outcome measurements that have elements of both. Twenty-four measure functional outcome, 3 pain, 10 sensations and proprioception, 9 quality of life, 8 satisfaction with the result, 5 measure the aesthetic outcome, 6 contours and flap stability and 21 contain multidomain elements. A multitude of different outcome measurements is currently used in lower extremity reconstruction So far, no consensus has been reached on what to measure and how. Validation and standardization of both PROMs and CROMs in plastic surgery is needed to improve the outcome of our patients, better meet their needs and expectations and eventually optimize extremity reconstruction by enabling a direct comparison of studies' results.

New, Innovative, Three-Dimensional In Vivo Model for High-Level Microsurgical and Supermicrosurgical Training: A Replacement for Animal Models

SUMMARY

Microsurgery and supermicrosurgery are surgical subdomains necessary for a large variety of surgical disciplines. So far, there is no training model for lymphatic surgery or perforator flap surgery, and the most commonly used microsurgical training models are living animals. However, the ethical principles of replacement, refinement, and reduction (the three Rs) of living animals for training purposes were implemented, highlighting the necessity of an animal-sparing microsurgical training model. Formed during embryogenesis, the chick chorioallantoic membrane resembles a highly vascularized, noninnervated membrane within fertilized chicken eggs. The aim of this study was to utilize the chorioallantoic membrane model as an innovative and versatile training model for supermicrosurgery and microsurgery that can reduce the number of animals used for these purposes. The variety of different sized vessels for the implementation of an anastomosis proved the chorioallantoic membrane model as a well-functioning supermicrosurgical and microsurgical training model. The circulatory system is resilient enough to withstand the mechanical stress applied to the tissue, and the patency of the implemented anastomosis can be tested for the verification of the procedures. In summary, the integration of the chorioallantoic membrane model into a surgical training program can benefit its quality by representing a realistic anatomical and physiological model with a high variety of vascular structures. Moreover, the chorioallantoic membrane model satisfies the principles of replacement, refinement, and reduction as an animal-sparing model, indicating the potential of this model as an innovative microsurgical training model for the improvement of surgical skills.

Quality of Life after Flap Reconstruction of the Distal Lower Extremity: Is There a Difference Between a Pedicled Suralis Flap and a Free Anterior Lateral Thigh Flap?

Background:

Flap reconstruction of the distal lower extremity is challenging. Especially, the concept of perforator surgery has increased available surgical options. Although results are generally judged in terms of objective facts, patients-perceived quality of life has largely remained unexamined. The aim of the study was to compare quality of life after lower extremity reconstruction with pedicled and free flaps.

Methods:

Patients were evaluated retrospectively after reconstruction of defects of the distal lower extremity either with distally based adipofascial sural flap (pedicled reverse sural flap) or an anterior lateral thigh (ALT) flap. A specific questionnaire was developed to measure the patient’s quality of life, based on short form health survey-12, Dresden Body Image Score-35, Patient Health Questionnaire-4, and X-SMFA questionnaires with additional specific questions. Furthermore, results, secondary surgeries, and complications were analyzed.

Results:

Thirty-seven patients with reconstruction of lower limb defects treated with a pedicled reverse sural flap and 34 patients treated with an ALT flap were included in the study. There was no statistical significant difference in the overall satisfaction with the procedure in the long-term follow-up between both groups, but patients with ALT showed a higher satisfaction with the treatment in the initial postoperative period. Both groups demonstrated approximately similar results in the long term for self-acceptance and vitality.

Conclusions:

Although anatomic situation may dictate flap choice coverage with free flaps, a less-complicated flap is by no means regarded as an inferior treatment option in patient’s estimation. Despite the intuitive speculation that patients with more advanced reconstruction methods should have better function and subsequently higher quality of life, this assumption was clearly not supported by data in this study.

Effectiveness of Vascularized Lymph Node Transfer for Extremity Lymphedema Using Volumetric and Circumferential Differences

Background

Circumferential difference of lymphedematous limbs at designated anatomic distances has been the primary mode for measuring lymphedematous extremities. Computed tomography (CT) imaging produces accurate, consistent, hygienic volume measurements and a direct limb representation. This study compares these 2 main modalities and assesses their correlation.

Methods

CT and circumferential difference measurements, costs, and correlation of patient limbs that received vascularized lymph node transfer were compared.

Results

Mean circumferential difference by tape measurement pre- and postoperatively was 31.4% ± 19.1% and 17.4% ± 8.8% for upper limbs and 43.2% ± 16.1% and 22.4% ± 12% for the lower limbs, respectively. Mean CT volumetric difference pre- and postoperatively were 36.1 ± 4.1% and 27.2 ± 2.8% for the upper limb and 46.2 ± 3.2% and 33.2 ± 2.1% for the lower limbs, respectively. CT volume measurements significantly correlated with their respective circumferential difference with Pearson correlation coefficient of r = +0.7, which was statistically significant (P = 0.03), indicating a strong positive correlation between circumferential difference and actual limb volume changes as determined by CT imaging. Circumferential differences are more cost effective than CT volume assessments in the domains of measurement frequency (P = 0.03), fee (P < 0.01), time (P = 0.03), total cost per year (P < 0.01), and cost/minute (P = 0.03).

Conclusions

Standardized circumferential differences that are currently used are comparable to unbiased CT volumetric measurements and can be used as a reliable, reproducible, minimally invasive, low cost, and accurate method of measuring the lymphedematous limbs.

Long-term functional, subjective and psychological results after single digit replantation

Objective

The aim of this study was to analyse the long-term functional, subjective, and psychological results after single-digit replantation.

Methods

Thirty cases of digital replantation (14 thumbs, 12 index fingers, 2 middle fingers, 1 ring finger, and 1 little finger) in 30 patients (7 females and 23 males) with a mean age of 44.2 years (20–65 years) were evaluated at the end of a mean follow-up time of 36 months (19–50 months). The active range of motion of joints, grip and pinch strength, cutaneous sensibility, upper-extremity functioning, and subjective satisfaction were determined using the Disability of Arm, Shoulder, and Hand (DASH) questionnaire and the Michigan Hand Outcomes questionnaire (MHQ). Psychological sequelae, including depression, anxiety, and posttraumatic stress disorder (PTSD), were assessed. A correlation analysis among variables was also performed.

Results

The mean score for the DASH questionnaire was 6.6 (range: 0–39.2). The symptom of cold intolerance occurred in 53% of the patients. Two patients were diagnosed with depression, and only one patient exhibited PTSD. The DASH score had a good statistical correlation with total grip strength, pinch grip strength, and static two-point discrimination (S-2PD) (P < 0.05). Several aspects of the MHQ were also statistically relevant to some or all of the three objective results. Furthermore, the grip strength showed significant correlation with DASH and most aspects of the MHQ in multivariate logistic regression analysis (P < 0.05).

Conclusion

Total grip strength is the most important factor positively related to subjective outcomes. The incidence rates of psychological symptoms after digit replantation are very low at long-term follow-up.

Level of evidence

Level IV, therapeutic study.

Challenges in measuring outcomes following digital replantation

In the early period of replantation surgery, the emphasis was on digit survival. Subsequently, with better microsurgical techniques and instrumentation, the focus has shifted to function and in recent years to consideration of cost-effectiveness. Despite over 40 years of effort in refining digital replantation surgery, a rigorous evaluation of the outcomes of digital replantation has not been performed. This is because of the many confounding variables that influence outcome comparisons. These variables include the mechanism of injury (guillotine, crush, avulsion), the injury itself (total, near total, subtotal, partial amputation), and the surgical procedure (replantation, revascularization). In addition, the traditional outcome measures (two-point discrimination, range of motion, grip strength, or the ability to return to work) are reported inconsistently and vary widely among publications. All these factors make meaningful comparison of outcomes difficult. The recent emphasis on outcome research and cost-effectiveness necessitates a rethinking in the way we report outcomes of digital replantation. In this article, the authors summarize the challenges in assessing outcomes of digital replantation and explain the need to measure outcomes using rigorous clinical research designs that incorporate cost-effectiveness studies in the research protocol.