Intraoperative angiography provides objective assessment of skin perfusion in complex knee reconstruction

Intraoperative angiography imaging correlates with wound complications following soft tissue sarcoma resection

For soft tissue sarcoma patients receiving preoperative radiation therapy, wound complications are common and potentially devastating. The purpose of this study was to assess the feasibility of intraoperative indocyanine green fluorescent angiography (ICGA) as a predictor of wound complications in these patients. A consecutive series of patients with soft tissue sarcoma of the extremities or pelvis who received neoadjuvant radiation and a subsequent radical resection received intraoperative ICGA with the SPY PHI device (Stryker Inc.) at the time of closure. Retrospective analysis of fluorescence signal along multiple points of the wound length was performed and quantified. The primary endpoint was wound complication, defined as delayed wound healing or wound dehiscence, within 3 months of surgery. Fourteen patients with preoperative irradiated soft tissue sarcoma were consecutively imaged. There were six patients with wound complications classified as "aseptic" in five cases. Using the ICGA, blinded surgeons correctly predicted wound complications in 75% of cases. During the inflow phase, a mean ratio of normal of 0.62 maximized the area under the curve (AUC = 0.90) for predicting wound complications with a sensitivity of 100% and specificity of 77.4%. During the peak phase, a mean ratio of normal of 0.55 maximized the AUC (0.95) for predicting wound complications with a sensitivity of 88.9% and a specificity of 100%. Intraoperative use of ICGA may help to predict wound complications in patients undergoing resection of preoperatively irradiated soft tissue sarcomas of the extremities and pelvis.

Can Laser-Assisted Indocyanine Green Angiography Be Used to Quantify Perfusion Changes During Staged Fixation of Pilon Fractures? A Pilot Study

OBJECTIVE

To quantify soft tissue perfusion changes in pilon fractures during staged treatment using laser-assisted indocyanine green angiography (LA-ICGA).

SETTING

Level 1 trauma center.

DESIGN

Prospective cohort study.

PATIENTS/PARTICIPANTS

Twelve patients with 12 pilon fractures participated in the study. Seven patients had OTA/AO classification of 43-C3, 3 had 43-C2, and 2 had 43-B2.

MAIN OUTCOME MEASURES

LA-ICGA was performed with the SPY fluorescence imaging platform. Analysis via ImageJ was used to generate a fractional area of perfusion (FAP) based on fluorescent intensity to objectively quantify soft tissue perfusion. Anterior, medial, and lateral measurements were performed at the time of initial external fixation (EF) application and then at the time of definitive fixation.

RESULTS

FAP within the region of interest was on average 64% medially, 61% laterally, and 62% anteriorly immediately before EF placement. Immediately before definitive open reduction internal fixation, fractional region of interest perfusion was on average 86% medially, 87% laterally, and 86% anteriorly. FAP increased on average 24% medially ( P = 0.0004), 26% laterally ( P = 0.001), and 19% anteriorly ( P = 0.002) from the time of initial EF to the time of definitive open reduction and internal fixation.

CONCLUSIONS

Quantitative improvement in soft tissue perfusion was identified through the course of staged surgical management in pilon fractures. LA-ICGA potentially may be used to determine appropriate timing for definitive surgical intervention based on the readiness of the soft tissue envelope. Ultimately, these findings may influence clinical outcomes with respect to choice of surgical approach, soft tissue management, surgical timing, and wound healing.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Revision TKA for Instability: Poorer Outcomes after a Previous Aseptic Revision

Instability is a common indication for early revision total knee arthroplasty (rTKA). The comparative performance of instability rTKA performed after primary TKA and instability rerevision TKA (rrTKA) performed after a previous rTKA performed for any aseptic indication have not been defined. This study was performed to determine the rate of adverse outcomes for patients undergoing aseptic instability TKA revision following a primary TKA or a previous aseptic any-cause rTKA. After obtaining Institutional Review Board approval, we retrospectively identified 126 rTKA and 28 rrTKA component revision procedures performed for an exclusive instability diagnosis between January 1, 2011 and April 30, 2018. We excluded patients undergoing isolated liner exchange, single component revision for mid-flexion instability, and patients treated with a constrained hinge. Patient demographic characteristics, medical comorbidities, time to initial revision TKA, and adverse postrevision outcomes (reoperation, component revision, infection, amputation) were assessed using paired Student's t-test or Fisher's exact test with a p-value < 0.05 used to determine significance. Patients in the rrTKA cohort were more commonly female (57.1 vs. 27.8%, p < 0.01), with no other demographic differences. The rrTKA cohort had higher reoperation (39.3 vs. 18.4%, p = 0.02) and component revision rates (25.0 vs. 8.7%, p = 0.03), with a trend towards early reoperation < 2 years after surgery (25.0 vs. 11.1%, p = 0.07). The rrTKA cohort also had higher adverse outcomes related to infection (14.3 vs. 1.6%, p = 0.01), extensor mechanism failure (14.3 vs. 3.2%, p = 0.04) and above-knee amputation (14.3 vs. 2.4%, p = 0.02). Component revision is beneficial for patients with TKA instability; however, higher adverse outcome rates occur after instability rrTKA performed after a previous aseptic any-cause rTKA. Infection prevention and extensor mechanism protection are important to minimize the most common adverse outcomes identified among patients undergoing aseptic rrTKA for instability.

Assessing Soft Tissue Perfusion Using Laser-Assisted Angiography in Tibial Plateau and Pilon Fractures: A Pilot Study

OBJECTIVES

To determine whether skin perfusion surrounding tibial plateau and pilon fractures is associated with the Tscherne classification for severity of soft tissue injury. The secondary aim was to determine if soft tissue perfusion improves from the time of injury to the time of definitive fracture fixation in fractures treated using a staged protocol.

DESIGN

Prospective cohort study.

SETTING

Academic trauma center.

PATIENTS

Eight pilon fracture patients and 19 tibial plateau fracture patients who underwent open reduction internal fixation.

MAIN OUTCOME MEASURES

Skin perfusion (fluorescence units) as measured by LA-ICGA.

RESULTS

Six patients were classified as Tscherne grade 0, 9 as grade 1, 10 as grade 2, and 2 as grade 3. Perfusion decreased by 14 fluorescence units (95% confidence interval, -21 to -6; P < 0.01) with each increase in Tscherne grade. Sixteen patients underwent staged fixation with an external fixator (mean time to definitive fixation 14.1 days). The mean perfusion increased significantly at the time of definitive fixation by a mean of 13.9 fluorescence units (95% confidence interval 4.8-22.9; P = 0.01).

CONCLUSIONS

LA-ICGA perfusion measures are associated with severity of soft tissue injury surrounding orthopaedic trauma fractures and appear to improve over time when fractures are stabilized in an external fixator. Further research is warranted to investigate whether objective perfusion measures are predictive of postoperative wound healing complications and whether this tool can be used to effectively guide timing of safe surgical fixation.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Free Flap Coverage for Complex Primary and Revision Total Knee Arthroplasty

BACKGROUND

Free flap coverage in the setting of a total knee arthroplasty is rare. The purpose of the current study was to evaluate the outcome of patients who underwent a free flap to assist with soft-tissue coverage following a complex total knee arthroplasty.

METHODS

The authors used their institutional total joint registry to retrospectively review patients undergoing a free soft-tissue flap in the setting of complex primary and revision total knee arthroplasty. Among 29,069 primary and 6433 revision total knee arthroplasties from 1994 to 2017, eight (0.02 percent) required a free flap for wound coverage. This included three primary total knee arthroplasties (0.01 percent) for posttraumatic arthritis and five revision total knee arthroplasties (0.07 percent) in the setting of infection. Median follow-up was 4 years.

RESULTS

Free flaps included vertical rectus abdominis (n = 3), anterior lateral thigh (n = 2), latissimus (n = 2), and transverse rectus abdominis (n = 1). There were no total flap losses; however, one patient required additional skin grafting. Reoperation occurred in six patients, of which four were revisions of the total knee arthroplasty for infection (n = 2) and tibial component loosening (n = 2). One patient ultimately underwent transfemoral amputation for persistent infection. Following reconstruction, there was improvement in the median Knee Society Score (49 versus 82; p = 0.03) and total range of motion between preoperative and postoperative assessments (70 degrees versus 85 degrees; p = 0.14).

CONCLUSION

Free flap coverage in the setting of total knee arthroplasty was associated with a high rate of reoperation; however, the limb was able to be preserved in the majority of patients, with a reasonable functional outcome.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Periorbital and Perioral Defect Reconstruction Using the Split Pre-Expanded Medial Arm Flap Aided by Using Indocyanine Green Angiography

ABSTRACT

The pre-expanded medial arm flap provides suitable skin for the resurfacing of a periorbital or perioral defect. However, the flap must be intraoperatively split to imitate the appearance of the oral or ophthalmic fissure, which can compromise flap perfusion. This study aimed to evaluate the safety and effectiveness of splitting pre-expanded medial arm flaps with the aid of indocyanine green angiography. All 8 patients underwent periorbital or perioral soft tissue reconstruction using a split pre-expanded medial arm flap. Flap splitting was aided by indocyanine green angiography. It was used during 2 stages of the procedure, tissue expander placement and flap transfer. The pedicle was divided 3 weeks later, and the flaps were used to resurface the defect. The distal portion of the flap was split into a fishmouth pattern in 5 patients and a window pattern in 3 patients. The donor sites were closed directly or by using a latissimus dorsi myocutaneous flap. There were no perioperative complications or flap necrosis. A pre-expanded split medial arm flap could be an option for the reconstruction of periorbital and perioral defects. With the assistance of indocyanine green angiography, vessel distribution and distal flap perfusion can be reliably evaluated, facilitating the safe splitting of the flap for the reconstruction of defects.

Peri-incisional perfusion does not differ between running versus interrupted Allgöwer-Donati suture technique in ankle fracture surgery: a pilot randomized controlled trial of wound perfusion

Objectives:

To compare peri-incisional perfusion, perfusion impairment and wound closure time between the conventional interrupted Allgöwer-Donati (IAD) technique and a modified running Allgöwer-Donati (RAD) technique in ankle fracture surgery.

Design:

Prospective, randomized controlled clinical trial.

Setting:

Level I and II trauma centers.

Patients:

Twenty-five healthy adults with ankle fractures (AO/OTA 44-A, 44-B, or 44-C) between November 2017 and December 2018. (Of 26 patients enrolled in this study, 1 was lost to follow-up.)

Intervention:

Participants were randomized into the IAD or the RAD group (13 patients each). All participants were followed for at least 3 months after surgery to assess for wound complications.

Main Outcome Measurements:

Skin perfusion was assessed immediately after wound closure with laser-assisted indocyanine green angiography. Wound closure time, mean incision perfusion, and mean perfusion impairment were measured and compared with analysis of variance. Alpha = 0.05.

Results:

The RAD technique was significantly faster in terms of mean (± standard deviation) wound closure time (6.2 ± 1.4 minutes) compared with the IAD technique (7.3 ± 1.4 minutes) (P = 0.047). We found no differences in mean incision perfusion and mean perfusion impairment (all, P > 0.05).

Conclusion:

The IAD and RAD techniques resulted in similar peri-incisional perfusion and perfusion impairment. Closure time was significantly shorter for the RAD technique compared with the IAD technique.

Level of Evidence:

I

Laser-Assisted Indocyanine Green Angiography in the Management of Open Ankle Fractures: A Technical Trick

Open ankle and pilon fractures in patients with poor soft-tissue quality represent a challenge for the treating orthopaedic surgeon. Occasionally, the typical transverse medial wound is very cephalad and does not allow for the proper visualization of the fracture. It is difficult to decide how to extend these open wounds to get access to the fracture while minimizing disruption of the blood supply to the skin. We describe the use of a new tool, laser-assisted indocyanine green angiography, to assist in incision planning for the definitive treatment of these injuries.

Impact of Skin Suture Pattern on Incision Perfusion Using Intraoperative Laser Angiography: A Randomized Clinical Trial of Patients With Ankle Fractures

OBJECTIVES

To assess which skin suture pattern-simple, vertical mattress, horizontal mattress, Allgöwer-Donati (AD), or running subcuticular-enables the greatest degree of perfusion as measured by indocyanine green laser angiography after ankle fracture surgery.

DESIGN

Prospective, randomized.

SETTING

Level 1 Academic Trauma Center.

PATIENTS/PARTICIPANTS

Seventy-five patients undergoing ankle fracture surgery were prospectively randomized to 1 of 5 skin suture patterns (n = 15 per cohort). Patient demographics and operative parameters were similar between groups.

MAIN OUTCOME MEASUREMENTS

Skin perfusion was assessed intraoperatively after skin closure using indocyanine green laser angiography and quantified in fluorescence units. Two perfusion values were collected: (1) mean incision perfusion was the mean of 10 points along the incision and (2) mean perfusion impairment was the perfusion difference between the incision and the skin adjacent to it. We also collected a postoperative patient scar assessment score.

RESULTS

Running subcuticular closure had significantly better mean incision perfusion than all other closure patterns. Mean perfusion impairment also favored running subcuticular closure, which was significantly lower than all other suture patterns except AD. We found no patient perceived cosmetic differences between the 5 suture pattern types.

CONCLUSIONS

Running subcuticular suture pattern resulted in the greatest incision perfusion than simple, horizontal mattress, vertical mattress, and AD techniques after ankle fracture fixation.

LEVEL OF EVIDENCE

Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

Application of Ice for Postoperative Total Knee Incisions - Does this Make Sense? A Pilot Evaluation of Blood Flow Using Fluorescence Angiography

Introduction

Total knee arthroplasty (TKA) is a common procedure with significant advances over the past several years, many pertaining to improved perioperative pain control. Cryotherapy is one method thought to decrease swelling and pain postoperatively. To our knowledge no study has directly visualized the effect cryotherapy has on skin blood flow following TKA. The primary aim was to determine if cryotherapy (icing) affects peri-incisional skin blood flow and if this is lessened with an alternate placement of the ice. We hypothesized that blood flow would decrease following cryotherapy, and this decrease would be greater with ice placed directly over the incision as compared to placement along the posterior knee.

Methods

This study included 10 patients who underwent TKA. During the postoperative hospitalization, they were given an injection of indocyanine green dye. A baseline image was recorded of the skin blood flow. Images were then collected following a five-minute interval placement of ice over the incision. The experiment was then repeated with the ice placed along the posterior knee. 

Results

There was an approximate 40% decrease in skin blood flow following placement of the ice compared to baseline. We observed a greater decrease in blood flow when ice was placed over the incision as compared to when ice was placed posterior to the knee (p ≤ 0.020).

Conclusion

We found a significant decrease in peri-incisional blood flow with icing of the knee. Physicians should be cognizant of this when recommending cryotherapy to patients after surgery, especially in at-risk wounds.

Pilot study to assess the use of a fluorescence imaging system for assessment of amputation healing

OBJECTIVE:

The purpose of this study was to use a fluorescence imaging system (FIS) (SPYElite, NOVADAQ, US) during lower extremity amputations and develop parameters to predict amputation healing, for which there are no proven, objective tests. We hypothesised that the FIS may identify areas of poor perfusion at the time of amputation and predict potential healing complications. There are no studies involving the FIS used in this study in lower extremity amputation.

METHOD:

This prospective cohort study involved patients requiring either below- or above-knee-amputation at one, mid-western medical centre. The FIS was used as per manufacturer's instructions after wound closure and before dressing. Procedure and operative management was unchanged. Through the FIS, perfusion values were plotted along the amputation site to visualise and quantify intraoperative perfusion and to compare with 30-day postoperative amputation healing.

RESULTS:

Surgeons determined that all of the 18 participants had adequate perfusion at surgical wound closure. At 30 days, two subjects had wound dehiscence or infection; these correlated with low perfusion values on the FIS imaging. A further six subjects had marginal or low perfusion values, but did not develop wound failure.

CONCLUSION:

It is feasible to use the FIS during amputation, however it did not perfectly predict healing course based on vascular perfusion. There were interesting patterns of poor perfusion that correlated with areas of dehiscence or infection but other patients had reduced perfusion that healed well. Due to the small sample size, no discernible perfusion value differences existed between patients who healed and patients with healing complications. A future, larger study may show that the FIS can be predictive of patient healing and aid decisions for intraoperative revision.

The Chitranjan Ranawat Award: Running Subcuticular Closure Enables the Most Robust Perfusion After TKA: A Randomized Clinical Trial

BACKGROUND

Maintaining robust perfusion is an important physiologic parameter in wound healing. The effect of different closure techniques on wound perfusion after total knee arthroplasty (TKA) has not been established previously and may have implications for wound healing.

QUESTIONS/PURPOSES

We asked whether a running subcuticular, vertical mattress, or skin staple closure technique enables the most robust wound perfusion after TKA as measured by laser-assisted indocyanine green angiography (LA-ICGA) in patients without specific risk factors for wound healing complications.

METHODS

Forty-five patients undergoing primary TKA without comorbidities known to impact wound healing and perfusion were prospectively randomized to receive superficial skin closure with one of the following techniques: (1) running subcuticular (3-0 monofilament); (2) vertical mattress (2-0 nylon); or (3) skin staples. Twenty procedures were performed by RTT, 15 by RJS, and 10 by FHS. All surgeons used an anterior skin incision over the medial third of the patella in combination with a median parapatellar arthrotomy. Perfusion was assessed with a LA-ICGA device and software system immediately after closure to quantify fluorescence. Twenty-seven points were assessed immediately after closure in the operating room in each patient (nine along the incision and nine pairs medial and lateral to the incision). Mean incision perfusion was determined from the nine points along the incision with higher values indicating greater blood flow. Mean perfusion impairment was determined by calculating the difference between the nine pairs of surrounding skin and the nine points along the incision with smaller values indicating less perfusion impairment. These parameters were compared with analysis of variance (ANOVA) and subsequent pairwise comparisons with an unadjusted analysis as well as a multivariate analysis that adjusted for age, sex, and body mass index. Patients were followed for a mean of 7 months after surgery (range, 3-12 months) for possible incision-related complications. No patents were lost to followup.

RESULTS

Running subcuticular closure demonstrated the best overall perfusion. Mean incision perfusion in fluorescent units with SD was as follows: running subcuticular, 64 (16); vertical mattress, 32 (18); and staples, 19 (7) (ANOVA p < 0.001). The running subcuticular closure demonstrated the least impairment of perfusion among the closures compared. Mean perfusion impairment was as follows: running subcuticular, 21 (12); vertical mattress, 37 (24); and staples, 69 (27) (ANOVA p < 0.001). All Tukey-adjusted pairwise comparisons from both metrics likewise favored the subcuticular closure (p < 0.001) both before and after adjusting for age, sex, and body mass index. One patient in the vertical mattress cohort experienced a surgical site infection; no other wound-related complications were observed in this study.

CONCLUSIONS

The method of closure can influence skin and soft tissue perfusion after TKA. Running subcuticular closure enables the most physiologic robust blood flow, which may improve wound healing. However, the clinical importance of these findings remains uncertain, because patients in this study were selected because they lacked risk factors for wound healing complications. Studies with this modality in specific patient populations at higher risk for wound complications will be necessary to quantify the clinical advantage of using running subcuticular closure.

LEVEL OF EVIDENCE

Level I, therapeutic study.

Posttraumatic Total Knee Arthroplasty Continues to Have Worse Outcome Than Total Knee Arthroplasty for Osteoarthritis

Small studies have shown that patients who undergo TKA following a distal femur and/or tibial plateau fracture have inferior results. The purpose of this study was to evaluate the mid-term outcomes of a large group of patients undergoing TKA following periarticular knee fractures. We identified 531 patients who underwent a TKA following a periarticular fracture from 1990 to 2012; comparing outcomes to 19,641 patients undergoing primary TKA for osteoarthritis. Periarticular fracture significantly increased the risk of revision TKA, infection and complications. There was no difference in the need for revision TKA or infection based on fracture location. Patients with TKA following a periarticular fracture have worse overall revision free survival compared to with OA, with 1 in 4 patients requiring revision TKA by 15 years.