Patent Popliteal Artery Research Articles

Below-knee Amputations Are Associated with Decreased Mortality and Reoperation in Elderly, Dependent Patients with Atherosclerotic Disease

Patients with dependent functional status are often offered above-knee amputations (AKAs), even if a below-knee amputation (BKA) could be an option, because AKA heals more easily than BKA. However, there is little data that directly compares the outcomes of these procedures in dependent patients to support this practice. The American College of Surgeons National Surgical Quality Improvement Program was used to identify functionally dependent patients who underwent non-traumatic BKA and AKA for atherosclerotic disease from 2005 to 2021. Emergent cases and those with preoperative sepsis and wound infections were excluded. The studied outcomes were 30-day mortality, major organ dysfunction, wound complications, and unplanned return to the operating room. Multivariable analysis was used. Institutional data from 2017 to 2022 on patients with BKA and AKA were included to provide more granular details about perfusion status of the legs by angiogram to predict the healing success of BKA. A total of 2399 patients were identified in the National Surgical Quality Improvement Program; 1039 underwent BKA and 1360 underwent AKA. BKA was associated with lower mortality (adjusted odds ratio [aOR], 0.60; P ≤ .001) and stroke (aOR, 0.14; P = .009) but higher wound complications (aOR, 1.87; P ≤ .001) and reoperation (aOR, 1.88; P ≤ .001) when compared with AKA (Table I). Preoperative imaging from 66 BKA patients was reviewed from institutional data to investigate factors associated with reoperation or BKA failure. There were 17 patients (25%) who failed a BKA and needed conversion to an AKA. Reoperation occurred at an average of 52 ± 37 days postoperatively. The status of the profunda appeared to make little difference; those failed BKA requiring AKA conversion were more likely to have occlusion of the popliteal artery when compared with those with successful BKA (69.2% vs 34.3%; P = .03) (Table II). Elderly, dependent patients requiring lower extremity amputation should initially be considered for BKA, as this is associated with decreased risk for mortality and reoperation when compared with AKA. Clinical judgement should be used in patients with popliteal occlusion, as this may contribute to BKA failure requiring conversion to AKA.Table IFactors predictive of mortality, wound complications, and reoperation in patients with below-knee amputation (BKA) and above-knee amputation (AKA)Adjusted odds ratio95% confidence intervalP-valueBKA MortalityHypoalbuminemiaa2.521.45-4.41.001Thrombocytopeniab2.681.41-5.08.003 Wound complicationsAge >70 years0.691.03-1.04.080 ReoperationAge >70 years0.560.32-0.83.004AKA MortalityChronic obstructive pulmonary disease1.611.03-2.51.036Congestive heart failure2.811.46-3.71<.001Dialysis dependence2.331.15-2.99<.001Steroid use2.171.15-4.10.017Thrombocytopeniab1.881.18-2.99.008 Wound complicationsBody mass index >30 kg/m21.931.14-3.28.014 ReoperationAge >70 years0.520.31-0.87.013Dialysis dependence1.891.05-3.37.031aSerum albumin less than 3.4 mg/dL.bSerum platelets less than 150 × 109/mL. Open table in a new tab Table IIPreoperative imaging scoring demonstrates prevalence of patent popliteal artery among patients with healed below-knee amputation (BKA) when compared with failed BKAHealed BKAFailed BKAP-valueTotal patients, n (%)4917Profunda stenosis.433 0-75% stenosis32 (91.4)10 (83.3) 76-100% stenosis3 (8.6)2 (16.7)Profunda disease length.091 0-2 cm34 (97.1)10 (83.3) 2->5 cm1 (2.9)2 (16.7)Patent popliteal23 (65.7)4 (30.8).030Patent SFA26 (74.3)10 (76.9).915Data are presented as number (%). Open table in a new tab

First Femoropopliteal Bypass for a Critical Limb Ischemia

First Femoropopliteal Bypass for a Critical Limb Ischemia

Alternative Combined Retrograde–Antegrade Use of a Re-entry Device in the Revascularization of a Surgically Ligated Superficial Femoral Artery Occlusion

AbstractWe report a case of a diabetic patient with critical limb ischemia, who previously underwent thromboendarterectomy at the right lower extremity, resulting in surgical ligation at the proximal third of the right superficial femoral artery (SFA). Twenty months later, the patient developed foot ulcers; endovascular treatment was therefore performed. After obtaining a retrograde right SFA subintimal access, directly puncturing the occluded segment of the artery, a re-entry intravascular ultrasound-guided catheter was used to gain proximal re-entry. Then, the same device was used again, in antegrade fashion, to obtain re-entry into the patent popliteal artery. A covered stent was deployed in the site of the surgical closure. In the following 3 months, foot ulcers healed.

How to proceed with a patent popliteal artery aneurysm below the chronic superficial femoral artery occlusion?

The indications for popliteal artery aneurysm treatment are clear. In aneurysms with patent inflow and outflow arteries, the risk of peripheral embolisation from amural thrombus is high and the treatment, mostly avascular intervention, is focused on preventing this extremity-threatening complication. It is unclear, however, how high the risk of peripheral embolisation is and how to proceed with apatent popliteal artery aneurysm fed by the deep femoral artery when the superficial femoral artery is chronically occluded. All patients diagnosed with popliteal artery aneurysm between 2015 and 2019 were searched in the database of the Department of Surgery II of University Hospital Olomouc. Patients with apatent popliteal artery aneurysm and chronic superficial femoral artery occlusion in the ipsilateral extremity were selected. We diagnosed 66 patients with 85 popliteal artery aneurysms. Four patients had apatent popliteal artery aneurysm and chronic superficial femoral artery occlusion in the ipsilateral extremity. In these patients, conservative treatment was indicated after the diagnosis was determined. In three patients, no clinically obvious complication of the popliteal artery aneurysm occurred. In one patient, popliteal artery aneurysm thrombosis occurred after afollow-up of 21 months, leading to ashortening of his calf claudication distance and limiting the patient. Our experience with this small group of patients shows the possibility of primary conservative treatment in patients with apatent popliteal artery aneurysm below the chronic superficial femoral artery occlusion site. Aneurysm thrombosis can be expected during follow-up. Patients in whom the thrombosis leads to limitations are indicated for surgical intervention. The risk of peripheral embolisation from the mural thrombus cannot be excluded with certainty. Further studies involving large groups of patients are needed to provide amore precise recommendation.

Ipsilateral Antegrade Angioplasty for Flush Superficial Femoral Artery Occlusion versus Open Bypass Surgery

Management of superficial femoral artery flush occlusion using the ipsilateral antegrade approach is challenging. The study aimed to assess technical feasibility, patency, and limb salvage of ipsilateral antegrade angioplasty versus surgery for this lesion in patients with lifestyle-limiting claudications and critical limb ischemia. Between June 2015 and March 2018, 53 patients were randomized to either ipsilateral antegrade angioplasty (n=28) or surgical bypass (n=25). We included patients with Trans-Atlantic Inter-Society Consensus IIB, C, or D lesions, having a patent popliteal artery. Technical success, patency, limb salvage, and major adverse events were assessed during the 12-month follow-up. The technical success was 100% and 89.3% in the surgical and endovascular groups, respectively (P=0.238). At 12 months, the primary, assisted, and secondary patency rates were 72% vs. 64.5%, 78.2% vs. 74.7%, and 81.6% vs. 74.2% in the surgical versus the endovascular groups, respectively, without significant differences between both groups. Limb salvage was 88% vs. 92% in the surgical versus the endovascular group, respectively (P=0.564). The length of hospital stay was longer in the surgical versus the endovascular group (6.24±0.37 vs. 1.84±0.19days, respectively, P=0.001). Local complications were higher in the surgical group (P=0.046). Technical success, patency, and limb salvage of endovascular approach were comparable to surgical bypass. The endovascular approach had the advantages of reduced local complications and hospitalization.

Role of Retrograde Trans-Popliteal Access for Surgical High-Risk Patients with TASC II-D Femoro-Popliteal Occlusive Disease: A Single Center Experience

Objectives: To compare the safety and efficacy of retrograde trans-popliteal access in total Superficial Femoral Artery (SFA) occlusions (TASK II-D) in surgical high-risk patients, in the presence of a patent popliteal artery, after unsuccessful antegrade lesion crossing attempts. Patients and methods: This is a retrospective study including 58 surgical high-risk patients with TASC II D femoro-popliteal occlusive diseases. After failure of antegrade access to cross the occlusion in 9 patients, medial retrograde trans-popliteal access was successfully achieved, followed by snaring of the retrograde wire through rendezvous technique. Perioperative complications and technical success were compared between different access groups. Results: 58 patients were included in the study; 15 men (25.9%) and 43 women (74.1%). 42 patients (72.4%) underwent contralateral retrograde access at Common Femoral Artery (CFA), 7 patients (12.1 %) ipsilateral antegrade access at CFA, 9 patients (15.5%) ipsilateral retrograde access at popliteal artery. All patients were ASA grade 4. Technical success was highest with contralateral retrograde entailing 40 cases (95.2%), followed by ipsilateral ante-grade access (6 cases - 85.7%) and lowest with ipsilateral retrograde (7 cases-77.8%). Conclusion: Transpopliteal retrograde approach can be utilized safely and efficiently using a medial infracondylar retrograde popliteal puncture, with the patient in the supine position. Furthermore, this retrograde popliteal approach can be considered a valid alternative for SFA or proximal PA recanalization after a failed antegrade approach, especially in high risk surgical patients (ASA 4).

Percutaneous chemical lumbar sympathectomy for buerger's disease: Results in 147 patients

Objectives: The objective of this study was to evaluate the efficacy, safety, and clinical outcome of percutaneous chemical lumbar sympathectomy (PCLS) in Buerger's disease (thromboangiitis obliterans [TAO]). Design: This was a retrospective comparative study. Methods: TAO patients who underwent PCLS in surgery department of a teaching hospital in Central India. Diagnosis of TAO was made on clinical grounds and color Doppler study. PCLS was done under image guidance after amputation of gangrene or before if a clear line of demarcation was lacking. After PCLS, patients were followed up on next day and after 2, 4, 8, and 12 weeks. Outcome monitored were improvement in rest pain (using visual analog scale) and healing of ischemic ulcers. Results: All patients were males, chronic bidi smokers, mostly in the third decade of life. All had involvement of lower limbs either ischemic rest pain or ischemic ulcers or gangrene of toes/forefoot. A total of 167 PCLS (20 bilateral) were performed on 147 TAO patients from June 2008 to January 2016. Imaging modalities were computed tomography scan (n = 67), digital X-ray (n = 50), and C-arm fluoroscopy (n = 50). Success rate for chemical neurolysis was > 82%. Excellent long-lasting rest pain relief was obtained in > 80% patients. Ulcer healing was seen in majority of patients. Large number of limbs (103/167) had gangrene of toe/multiple toes/part of forefoot. Those with patent popliteal artery fared better. Conclusions: PCLS can provide safe and efficient treatment for rest pain and healing of ischemic ulcers in TAO.

Anatomical Popliteal Artery Entrapment Syndrome Caused by an Aberrant Plantaris Muscle.

Purpose:We report on cases of anatomical popliteal artery entrapment syndrome (PAES) caused by an aberrant plantaris muscle and highlight the involvement of this muscle in PAES.Materials and Methods:Seven symptomatic PAES legs in six patients treated at The Division of Vascular Surgery, Asan Medical Center, Seoul, Korea, between 1995 and 2011 were included in this study. We retrospectively analyzed patient records, magnetic resonance imaging (MRI) and/or computed tomography (CT) scans of the knee joint, Doppler pressure studies, CT angiographies, and conventional femoral arteriographies.Results:Five males and one female patient with a median age of 32 (18–53) years old were enrolled in the study. All patients complained of intermittent claudication of the affected leg. All aberrant plantaris muscles were higher and more medially located than normal plantaris muscles, causing occlusion of the popliteal artery upon forced plantar flexion of the ankle. For arterial lesions, five occlusions of the popliteal artery and two patent popliteal arteries with positive provocation were noted. As for treatment, myotomy of the aberrant plantaris muscle was done for two non-occlusive PAES legs. For occlusive PAES legs, one thrombectomy, one saphenous vein graft interposition of the popliteal artery followed by myotomy, and two below-knee femoro-popliteal bypasses were performed. The median follow-up period was 88 (7–148) months.Conclusion:An aberrant plantaris muscle can cause anatomical PAES. Classification or diagnosis of PAES should be based on axial studies using CT scans or MRI using various reconstruction methods. Treatment, including myotomy of the plantaris muscle, should be individualized.

Alexis Carrel, Rene Leriche, Jean Kunlin, and the history of bypass surgery

Alexis Carrel, Rene Leriche, Jean Kunlin, and the history of bypass surgery

Dynamic Computed Tomography Angiography: Role in the Evaluation of Popliteal Artery Entrapment Syndrome

This study reviews our experience with dynamic computed tomographic angiography (CTA) as an imaging modality in the evaluation of popliteal artery entrapment syndrome (PAES). Eight patients with surgically proven PAES were included in this study. Dynamic CTA studies performed with the feet in neutral and plantar flexed positions were reviewed for the detailed anatomy of the region and to define the location and extent of the stenosis, occlusions and collateral circulation. These findings were compared with intraoperative observations. CTA provided adequate angiographic and anatomic information required to arrive at the diagnosis and make a surgical decision. Thirteen limbs were affected in eight patients. There was popliteal artery occlusion in four limbs, stenosis at rest that was accentuated on stress imaging in two limbs, and patent popliteal artery with marked stenosis on stress imaging in seven limbs. Long-segment stenosis was seen in functional entrapment compared to short-segment stenosis in anatomic PAES. Anteroposterior compression of the popliteal artery in anatomic PAES unlike the side-to-side compression in functional PAES was a unique observation in this study. The CTA and surgical characterisation and classification of PAES matched in all the patients, except for misinterpretation of compressing fibrous bands as accessory slips of muscles in three limbs. In conclusion, dynamic CTA is a robust diagnostic tool that provides clinically relevant information and serves as a rapidly performed and easily available "one-stop-shop" imaging modality in the management of PAES.

Rheolytic thrombectomy, angioplasty, and selective stenting for subacute isolated popliteal artery occlusions

We have observed that some patients with isolated popliteal artery occlusions (PAOs) harbor varying degrees of organized clot, as suggested by the rapidity with which these occlusions are traversed with the Glidewire. We hypothesized that debulking such PAOs by using rheolytic thrombectomy without adjunctive thrombolysis before percutaneous transluminal angioplasty and selective stenting (PTA/S) is safe and enables single-session treatment with minimal risk of embolization. Between February 2004 and January 2007, 16 male patients (mean age, 68.9 +/- 11.1 years; range, 54-84 years) presenting with disabling claudication (n = 1), rest pain (n = 5), and tissue loss (n = 10; mean duration, 11 +/- 8 weeks; range, 4-26 weeks) were prospectively followed up after rheolytic thrombectomy and angioplasty and selective stenting of their PAO. The mean occlusion length was 11.6 +/- 4.5 cm. After rheolytic thrombectomy, the occlusions were converted to long stenoses (mean length of 7.6 +/- 3.6 cm). Self-expanding stents were used in 10 of 16 (mean length of 8.3 +/- 4.4 cm). Additional recanalizations of occlusions of the iliac artery and proximal superficial femoral artery were performed before popliteal artery recanalizations in two patients. Ankle-brachial indexes increased from 0.27 +/- 0.22 to 0.94 +/- 0.13. No case of distal embolization was observed. Adjuvant thrombolysis was used in only one case to improve runoff. Inline flow to the foot was achieved in 15 of 16 cases. Three occlusions occurred at 3, 6, and 20 months after surgery (mean follow-up, 15.7 +/- 10.0 months), and two patients underwent successful thrombolysis. The third patient refused further intervention and remains a claudicant. One-year primary and secondary patency rates were 84% and 92%, respectively. Two limb losses occurred at 7 and 9 months as a result of recurrent foot infection in patients with diabetes, both with patent popliteal arteries (1-year limb salvage rate, 83%). We advocate debulking isolated subacute PAOs with rheolytic thrombectomy when they are easily crossed, because this enables recanalization of these lesions in a single setting, thus obviating the additional need for thrombolysis in most cases, with seemingly minimal risk of distal embolization. This simple approach is effective and widely available.

Duplex Arteriography Prior to Femoral-Popliteal Reconstruction in Claudicants: A Proposal for a New Shortened Protocol

The standard preoperative duplex arteriography (DA) from the aorta to the pedal vessels is time consuming and may be unnecessary in patients presenting with calf claudication alone. The feasibility of a shortened protocol was evaluated. Of 286 femoral-popliteal reconstruction based on DA during the last 4A years, 79 (28%) were primary operations for calf claudication. Eliminating the aortoiliac portion of the test except for the distal external iliac artery and limiting the scanning of the infrapopliteal vessels to one or two arteries in the leg would significantly shorten the exam. To confirm the adequacy of the inflow tract, we relied on the common femoral artery Doppler waveform analysis and the intraoperative graft pressure upon completion of the bypass. Of the 79 primary femoral-popliteal bypasses, 53 (67%) had triphasic common femoral artery waveform and the remaining 26 had monophasic or biphasic waveforms. Three (6%) of the 53 femoral-popliteal bypasses in the former group had significant pressure gradients measured intraoperatively and were treated with iliac angioplasties and stents for unsuspected stenoses in 2 cases and a covered stent for a common iliac aneurysm in 1 case. Three, two, and one infrapopliteal vessel runoff was observed in 24 (45%), 16 (30%), and 9 (17%) extremities, respectively. Four patients (8%) had significant stenoses (>50%) or occlusion of all three infrapopliteal arteries. Eighty-one percent of the patients would have completed the short protocol had we scanned the peroneal artery initially. An additional 8% would have required scanning of a second vessel (anterior tibial) and only 11%, scanning of all three infrapopliteal vessels. The time interval for completion of short-protocol DA was significantly less than the time for the standard DA (16.2 A+/- 5.2A min vs. 35.1 A+/- 10.6 min) ( p < 0.01). We believe that the proposed short DA protocol combined with intraoperative graft pressure measurements can be used in 94% of the patients who have a patent popliteal artery (>/= 7 cm). It is a totally noninvasive approach that is particularly suitable for vascular technologists and surgeons who wish to start utilizing DA instead of contrast arteriography prior to infrainguinal reconstructions. However, the short protocol does not avert the need for completion arteriography of the inflow arteries and readiness to perform endovascular procedures to correct lesions not suspected by common femoral artery waveform analysis.

Popliteal Artery Entrapment Syndrome: Arteriographic Findings and Thrombolytic Therapy

To review the arteriographic appearance of popliteal artery entrapment syndrome (PAES) and functional popliteal artery entrapment, and determine the role of thrombolysis in the treatment of these disorders. Retrospective review of hospital records from 1991 to 1998. Seven patients with PAES and one with functional entrapment were identified. The popliteal artery was occluded in two limbs and compressed in 13. Active plantar flexion was necessary to demonstrate impingement in nine limbs. Medial deviation of the popliteal artery was evident in six of 14 patent popliteal arteries, and lateral deviation was observed in one limb. "Classic" abrupt medial angulation of the popliteal artery was observed in one limb. Both limbs were involved in all six patients who underwent bilateral popliteal exploration. Thrombolytic therapy was performed in three limbs. In two instances, it permitted a less extensive surgical procedure than would otherwise have been required. There is considerable variability in the arteriographic appearance of PAES, which is arteriographically indistinguishable from functional entrapment. It is frequently bilateral. Thrombolytic therapy does not obviate surgery but may permit a less extensive procedure to be performed.

Balloon-expandable endobypass for femoropopliteal atherosclerotic occlusive disease. A preliminary evaluation of fifty-five patients.

The purpose of this study was to evaluate the early results of a newly developed endovascular technique for the treatment of superficial femoral artery occlusion. Fifty-five patients with total occlusion of the superficial femoral artery with patent popliteal artery were treated and evaluated over a 21-month period. The endovascular treatment was performed through a groin incision and consisted of a recanalization of the occluded femoral artery, balloon dilatation, and intraluminal placement of a 3-mm polytetrafluoroethylene graft, distal fixation with a stent, dilation of the graft, and proximal suture anastomosis in the common femoral artery. At a 1-year follow-up the Kaplan-Meier method revealed a primary patency rate of 73.1% (95% confidence limits: 59.6 to 86.6) and a secondary patency rate of 86.3% (range 75.8% to 96.9%). The procedure morbidity rate was 3.6%; the mortality and amputation rate at 12 months was nil. The early 1-year results of this endovascular study support the concept that femoropopliteal endobypass for atherosclerotic occlusive disease may be an acceptable alternative to classic direct femoropopliteal bypass operations. Further study is necessary.

Intermittent calf and foot compression increases lower extremity blood flow

Although foot compression increases foot skin perfusion and calf compression increases popliteal artery blood flow, these compression techniques have not been evaluated in combination. The purpose of this study was to evaluate whether calf and foot compression applied separately and simultaneously increase popliteal artery blood flow and/or foot skin perfusion, and to assess the relative merits of compression in patients with superficial femoral artery occlusion. Twenty-two legs from 12 normal volunteers with ankle/brachial indices (ABIs) > 0.96, and 10 legs from 7 claudicator patients with angiographically documented superficial femoral artery (SFA) occlusion and patent popliteal arteries with ABIs < 0.8 were studied in the sitting position. Calf and foot cuffs connected to a rapidly inflating and deflating timed-pressure pump (Art-Assist-AA 1000; ACI Medical Inc., San Marcos, California) were applied to the subject in the sitting position. Skin blood flow of the great toe was measured with a laser doppler (Laserflo model BPM 403A; TSI Inc., St. Paul, Minnesota), and popliteal artery blood flow was measured using duplex ultrasonography (ATL-Ultramark 9; Advanced Tech Laboratory, Bothell, Washington). Foot and calf compression was applied separately and simultaneously at 120 mm Hg pressure, with a 10-second inflation and 20-second deflation cycle. Popliteal artery blood flow and foot skin perfusion were recorded and the mean of 6 cycles calculated. Precompression popliteal artery blood flow (mL/min) for volunteers was 38.86 +/- 3.94, and for patients was 86.30 +/- 14.55 (P = 0.001). Precompression foot skin perfusion (mL/min/ 100/g tissue) for volunteers was 1.67 +/- 0.29, and for patients was 4.00 +/- 0.92 (P = 0.01). With the application of calf, foot, and simultaneous calf and foot compression, the popliteal artery blood flow increased in volunteers by 124%, 54%, and 173%, respectively, and in patients by 76%, 13%, and 50%. Foot skin perfusion increased in volunteers by 260%, 500%, and 328%, respectively, and in patients by 116%, 246%, and 188%. Relative increases in popliteal artery blood flow and foot skin perfusion were higher in volunteers compared with patients during compression; however, the absolute values for foot skin perfusion and popliteal artery blood flow were consistently higher in patients. Measured in the sitting position, the resting popliteal artery blood flow and foot skin perfusion are greater in patients with SFA occlusion compared with normal volunteers. Following compression, popliteal artery blood flow and foot skin perfusion increased in both groups, but relatively more in volunteers. Increases in popliteal artery blood flow are significantly higher with calf compression than with foot compression for both groups. A patent SFA allows for additive increases in popliteal artery blood flow with simultaneous foot and calf compression in normal persons, whereas this is not observed in patients. However, the increases in foot skin perfusion in patients with an occluded SFA parallel the increases shown in normal volunteers, with separate and simultaneous foot and calf compression.

The place of profundaplasty in the surgical treatment of superficial femoral artery occlusion

One-hundred and sixty-three patients in whom an isolated profundaplasty was performed as treatment for superficial femoral artery occlusion were evaluated for postoperative improvement, taking into consideration the degree of stenosis of the profunda origin and the patency of peripheral vessels. One-hundred and eleven (68.1%) patients achieved clinical improvement. Fifty-two patients had to undergo amputation (27 below the knee and 19 above the knee) or distal reconstruction (6 patients) because of unrelieved ischaemia. In patients with Fontaine stage II and III disease (89% and 70% respectively) improvement was observed more often than in those with stage IV disease (53%). Half of the patients had an increase of the resting systolic ankle-brachial arterial pressure index, but the rise was only slight (0.12 +/- 0.1). While radiological information of the presence and degree of a stenosis had little influence on the operative outcome stenosis at the origin of the profunda, when seen and described at operation, resulted in a more frequent improvement in the clinical state and systolic ankle-brachial arterial pressure index. A patent popliteal artery was not necessary for a favourable outcome but the number of patent tibial arteries was important. Whenever two tibial vessels were patent, relief was achieved in 75% of the cases: the existence of one patent tibial artery produced improvement in 64% but if all were occluded only 31% showed improvement. In cases of severe ischaemia, success following profundaplasty is limited and the results are often inadequate. If at least one tibial artery is patent, the alternative is a femoro-crural reconstruction.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascularised whole knee joint allografts in rabbits immunosuppressed with cyclosporin A

To develop the surgical model, whole knee joints including the distal femur, proximal tibia, and joint capsule, were raised on a vascular pedicle and then replanted at the same site. Rigid fixation of the bones was achieved using two mini-plates on the tibia and femur. Revascularization of the knee was accomplished by end-to-end anastomosis of the popliteal vessels using standard microvascular techniques, and the vascular and neural supplies to the lower leg and foot were preserved. A total of 21 vascularized whole knee allografts were then similarly performed on a microvascular pedicle between two incompatible strains of rabbit. In a control group of six adult animals, no immunosuppression was administered. Two of these joints were harvested at 1 week and had patent popliteal arteries. The remaining four joints were harvested at 2–3 weeks when they were deteriorating and were found to have occluded popliteal vessels by arteriography. Eight adult allograft recipients were immunosuppressed with cyclosporin A (CyA) at 15 mg/kg per day. One allograft failed at 10 days due to femoral fracture. None of the remaining seven were rejected acutely, and three of them had patent vessels by arteriography and live bone and cartilage by light microscopy when harvested 100 days after transplantation. In another group, seven knee joints were allografted into immature rabbits immunosuppressed with CyA. Again, none rejected acutely, and 90 days later two of the seven allografts had patent vessels by arteriography, growth by serial radiographs, and live bone and cartilage by histological examination. This pilot study suggests that CyA will be useful as an immunosuppressive agent in the study of vascularized bone and cartilage transplantation, and that experimental epiphyseal plate allografting is possible in rabbits.

Vascularized whole knee joint allografts in rabbits immunosuppressed with cyclosporin A.

To develop the surgical model, whole knee joints including the distal femur, proximal tibia, and joint capsule, were raised on a vascular pedicle and then replanted at the same site. Rigid fixation of the bones was achieved using two mini-plates on the tibia and femur. Revascularization of the knee was accomplished by end-to-end anastomosis of the popliteal vessels using standard microvascular techniques, and the vascular and neural supplies to the lower leg and foot were preserved. A total of 21 vascularized whole knee allografts were then similarly performed on a microvascular pedicle between two incompatible strains of rabbit. In a control group of six adult animals, no immunosuppression was administered. Two of these joints were harvested at 1 week and had patent popliteal arteries. The remaining four joints were harvested at 2-3 weeks when they were deteriorating and were found to have occluded popliteal vessels by arteriography. Eight adult allograft recipients were immunosuppressed with cyclosporin A (CyA) at 15 mg/kg per day. One allograft failed at 10 days due to femoral fracture. None of the remaining seven were rejected acutely, and three of them had patent vessels by arteriography and live bone and cartilage by light microscopy when harvested 100 days after transplantation. In another group, seven knee joints were allografted into immature rabbits immunosuppressed with CyA. Again, none rejected acutely, and 90 days later two of the seven allografts had patent vessels by arteriography, growth by serial radiographs, and live bone and cartilage by histological examination. This pilot study suggests that CyA will be useful as an immunosuppressive agent in the study of vascularized bone and cartilage transplantation, and that experimental epiphyseal plate allografting is possible in rabbits.

Modified Catheter for Percutaneous Transluminal Treatment of Arteriosclerotic Obstructions

Experience with transluminal dilatation of superficial femoral artery stenoses resulted in modification of the original outer catheter because of the following problem. The patient in Figure 1, A and B had generalized arteriosclerosis and one severely stenotic segment in the superficial femoral artery at the adductor hiatus. Although containing some atheromatous plaques, the popliteal artery was patent. Transluminal dilatation was carried out by the method of Dotter and Judkins (1–3). No difficulty was encountered in dilating the stenotic segment with the wire guide or with the small catheter. After the stenosis was traversed by the larger catheter, arteriography showed that the previously stenotic segment was now wide open. A stenosis had developed in the originally patent popliteal artery (Fig. 1, C), however, and atheromatous material had apparently been deposited in the lumen of the popliteal artery. I postulated that the difficulty arose from a “snow-plow” effect due to a small ridge which formed around the second catheter when it was passed over the first. A roentgenogram (Fig. 2, A) of the original catheters shows this sharp ridge formed by the junction of the leading edge of the outer catheter and the outside surface of the inner catheter. In a tight stenosis first traversed by the tapered inner catheter, the ridge of the outer catheter can push atheromatous material ahead of it rather than compress it to the sides of the lumen as was originally intended (Fig. 3, A). This thesis is supported by the appearance of the vessel wall at the original superficial femoral artery stenosis following dilatation. The step-like configuration suggests a gouging out of an atheromatous plaque (Fig. 1, C, arrow). The manufacturer2 modified the larger catheter so that the tip was molded to the diameter of the wire guide. Figure 2, B demonstrates the relationship of the modified outer catheter to the inner catheter and guide. The outer catheter has a smooth transition from the wire guide to its greatest diameter. The smooth change in diameter allows the tip of the catheter to occupy the space previously dilated by the smaller catheter. The proximal gradually widening larger tube then compresses the atheromatous material against the vessel wall (Fig. 3, B). With this arrangement the larger catheter cannot be passed over the smaller tubing. Therefore, after dilatation has been accomplished with the smaller catheter, it is removed and the larger catheter is inserted over the wire guide. This is no different from exchanging catheters in any vascular diagnostic catheter procedure. If more stiffness is required, the smaller catheter can be reintroduced inside the larger catheter. If this is not sufficient, a long metal cannula provided by the manufacturer can be passed over the wire guide inside the smaller catheter to increase stiffness in penetrating the stenosis.