Popliteal artery injury (PAI) is a feared complication during knee replacement. Our aim was to investigate those injuries that occurred in association with knee replacement in terms of the type of injury, treatment and outcomes. From our national vascular registry (Swedvasc) and the Swedish Patient Insurance databases a total of 32 cases were identified. Prospective data from the registries was supplemented with case-records, including long-term follow-up. We estimated the incidence during 1998 to 2010 to be 0.017%. In our series of 32 patients with PAI occurring between 1987 and 2011, 25 (78%) were due to penetrating trauma and seven were caused by blunt trauma. The patients presented in three ways: bleeding (14), ischaemia (7) and false aneurysm formation (11), and five occurred during revision surgery. A total of 12 injuries were detected intra-operatively, eight within 24 hours (3 to 24) and 12 at more than 24 hours post-operatively (2 to 90 days). Treatment comprised open surgery in 28 patients. Patency of the vascular repair at 30 days was 97% (31 of 32, one amputation). At the time of follow-up (median 546 days, mean 677 days (24 to 1251)), 25 patients had residual symptoms. Of seven patients with a complete recovery, six had had an early diagnosis of the PAI during the procedure, and were treated by a vascular surgeon in the same hospital. PAI is a rare adverse event during knee replacement surgery. The outcome following such events is often adversely affected by diagnostic and therapeutic delay. Bleeding and false aneurysm were the most common clinical presentations. Cite this article: Bone Joint J 2013;95-B:1645–9

We report a case in which the popliteal artery was divided during upper tibial osteotomy performed with the knee in 90 degrees of flexion. This position is believed to allow it to fall safely back from the tibia, but we could find no published confirmation. We used duplex ultrasonography in ten healthy volunteers to measure the distance from the popliteal artery to the posterior surface of the tibia at various degrees of flexion of the knee. Our results showed that in 12 of 20 knees the popliteal artery was closer to the tibia in 90 degrees of knee flexion than in full extension. Surgeons performing upper tibial osteotomy should be aware that flexing the knee does not protect the popliteal artery from injury

Total knee replacements and high tibial osteotomies are commonly performed orthopaedic operations with low complication rates. Both of these procedures involve surgery in close proximity to the popliteal artery with the use of power tools and sharp instruments. The behaviour of the popliteal artery during knee flexion, in particular the change in distance between itself and the posterior tibial cortex, is poorly understood. Many previous studies have been on stiff embalmed knees or with the patient lying supine, so as to subject the popliteal artery to an anterior pull from gravity. We used duplex ultrasonography on 100 healthy knees to determine the distance of the popliteal artery from the posterior tibial surface at 0 and 90 degrees of flexion. One observer was used throughout. At 1–1.5cm below the joint line, we found the artery was closer to the posterior tibial surface in 24% of knees when the knee was flexion. This was also the case for 15% of knees at 1.5–2cm below the joint line. These two levels were chosen as they represent the usual positions for the tibial cuts performed in total knee replacement and tibial osteotomy. We provide an anatomical account to help explain our findings using cadaveric dissections, arteriography and static MRI studies. The first of our explanations for this posterior movement of the artery is the increase in the antero-posterior thickness of the popliteus muscle during knee flexion. We also observed a posterior pull on the popliteal artery from the sural vessels. 6% of the knees had a high branching anterior tibial branch. We highlight this anatomical variant as an example of an extremely vulnerable vessel. We review the existing literature regarding the popliteal artery dynamics, and conclude that 90 degrees of knee flexion is the safer position for tibial procedures, but repeat the warning that the surgeon must still take great care

We have investigated iatrogenic popliteal artery injuries (PAI) during non arthroplasty knee surgery regarding mechanism of injury, treatment and outcomes, and to identify successful strategies when injury occurs. In all, 21 iatrogenic popliteal artery injuries in 21 patients during knee surgery other than knee arthroplasty were identified from the Swedish Vascular Registry (Swedvasc) between 1987 and 2011. Prospective registry data were supplemented with case-records, including long-term follow-up. In total, 13 patients suffered PAI during elective surgery and eight during urgent surgery such as fracture fixation or tumour resection. Nine injuries were detected intra-operatively, five within 12 to 48 hours and seven > 48 hours post-operatively (two days to 23 years). There were 19 open vascular and two endovascular surgical repairs. Two patients died within six months of surgery. One patient required amputation. Only six patients had a complete recovery of whom had the vascular injury detected at time of injury and repaired by a vascular surgeon. Patients sustaining vascular injury during elective procedures are more likely to litigate (p = 0.029). We conclude that outcomes are poorer when there is a delay of diagnosis and treatment, and that orthopaedic surgeons should develop strategies to detect PAI early and ensure rapid access to vascular surgical support. Cite this article: Bone Joint J 2015;97-B:192–6

Purpose: Knee dislocation is associated with blunt popliteal artery trauma in almost 30% of cases. In such injuries, prompt diagnosis and appropriate management is essential for limb salvage. Both our methods and outcomes of popliteal artery thrombosis treatment after knee dislocation are presented in this retrospective study. Methods: During the last six years, eight patients (all male, average age 25 years) were admitted to our hospital with knee dislocation and associated blunt popliteal artery thrombosis following automobile accidents (7/8) and fall from height (1/8). The average delay before accessing the emergency room was 14 hours (ranging from 2 to 24 hours). Seven patients were experiencing signs of distal ischemia (absence of distal pulses, motor and sensory loss) and one patient, admitted two hours after vehicle accident, was presented with absent distal pulses but maintained motor and sensory ability. Seven patients underwent external fixation and one plaster cast immobilization. In all cases, digital subtraction arteriography was performed. Results: All patients were treated by performing below knee femoropopliteal bypass, using reversed saphenous vein in seven cases and a vscs graft in one. All patients underwent fasciotomies. One above knee amputation was performed postoperatively while three patients experience permanent neurologic discrepancy. Conclusions: In any case of knee dislocation, there must be a high clinical suspicion of popliteal artery thrombosis. Meticulous and repeated physical examination and rapid admission to a department of vascular surgery are of vital importance for limb salvage and minimization of amputation rate and permanent neurologic deficiency

Purpose. We aim to determine the amputation rate and identify predictors of outcome in patients with tibial fractures and associated popliteal artery injuries at a level 1 trauma unit draining a large geographical region. Material and methods. All patients with popliteal artery injuries and tibial fractures treated at a level 1 trauma unit between 1999 and 2010 were assessed retrospectively regarding amputation rates and prognostic factors and tested for significance with a Z-test of proportions. Results. Thirty consecutive patients were reviewed with a mean age of 30.5 years and a male preponderance of 73.3%. Motor vehicle accidents (MVAs) and gunshot wounds (GSWs) constituted the mechanism of injury in 17 patients (56.7%) and 11 patients (36.7%) respectively. Twenty-one cases were polytrauma patients. Intra and extra-articular metaphyseal fractures (AO 41 A-C) were seen in 19 patients and diaphyseal fractures (42 A-C) in 7 patients. Primary amputation was performed in 7 patients and delayed amputation in 10 patients giving an overall amputation rate of 56.7%. Amputation rates in MVAs and GSWs were similar (57.9% and 54.5% respectively). Delays from injury to revascularization of more than 6 hours, delays from hospital admission to revascularization of more than 2 hours and initial clinical assessment of non-viability were associated with higher rates of limb loss of 60.9%, 62.5% and 60% respectively. Signs of threatened viability together with delay from admission to theatre more than 2 hours showed the highest amputation rate of 68,4%. These results are trends and not statistically significant with 95% confidence interval. Conclusion. More than half of the patients with these injuries required amputation. Predictors of amputation remain elusive; however, these results suggest that initial presentation of a threatened limb in the context of a tibial fracture may necessitate intervention within the first 2 hours of presentation in order to improve the outcome. NO DISCLOSURES

Injury to the popliteal artery is reported in two patients with closed ligament injuries of the knee, and no fracture or dislocation. The importance of careful assessment of the circulation in this type of patient is emphasised

Total knee replacement and high tibial osteotomy are common orthopaedic operations with low complication rates. Such surgery is in close proximity to the popliteal artery (PA), the behaviour of which during flexion of the knee is poorly understood. We used Duplex ultrasonography to determine the distance of the PA from the posterior tibial surface at 0° and 90° of flexion in 100 knees. When the knee was flexed the PA was closer to the posterior tibial surface at 1 to 1.5 cm below the joint line in 24% and at 1.5 to 2 cm below the joint line in 15%. There was a high branching anterior tibal artery in 6% of knees. We provide an anatomical account to help to explain our findings by using cadaver dissections, arteriography and static MRI studies

1. A clinico-pathological study of a patient who suffered traumatic rupture of his right popliteal artery is outlined. 2. Collateral circulation from the genicular anastomosis developed within twenty hours. 3. Ischaemic necrosis of the belly of the tibialis anterior occurred, but voluntary power began to return about twenty-one weeks after injury. 4. Biopsy of the muscle nineteen, fifty-seven and seventy-six weeks after injury showed that the muscle belly was being reconstituted by new fibres and that the ischaemic tissue remained entombed in the deepest part of the muscle. The regenerating fibres arose from small numbers of subfascial fibres which either survived the ischaemic episode or had arisen by myoblastic differentiation of connective tissue cells. Sarcoplasmic outgrowths produced new contractile substance, and new fibres were formed by amitotic fission. Many of the fibres matured and the regenerative process was still active seventy-six weeks after injury. 5. Growth of new nerve bundles containing myelinated axons accompanied the development of new muscle fibres

Introduction. Regional anesthesia is commonly utilized to minimize postoperative pain, improve function, and allow earlier rehabilitation following Total Knee Arthroplasty (TKA). The adductor canal block (ACB) provides effective analgesia of the anterior knee. However, patients will often experience posterior pain not covered by the ACB requiring supplemental opioid medications. A technique involving infiltration of local anesthetic between the popliteal artery and capsule of knee (IPACK) targets the terminal branches of the sciatic nerve, providing an alternative for controlling posterior knee pain following TKA. Materials and Methods. IRB approval was obtained, a power analysis was performed, and all patients gave informed consent. Eligible patients were those scheduled for an elective unilateral, primary TKA, who were ≥ 18 years old, English speaking, American Society of Anesthesiologists physical status (ASA PS) classification I-III. Exclusion criteria included contraindication to regional anesthesia or peripheral nerve blocks, allergy to local anesthetics, allergy to nonsteroidal anti-inflammatory drugs (NSAIDs), chronic renal insufficiency with GFR < 60, chronic pain not related to the operative joint, chronic (> 3 month) opioid use, pre-existing peripheral neuropathy involving the operative limb, and body mass index (BMI) ≥ 40 kg/m. 2. . Patients were randomized into one of two treatment arms: Continuous ACB with IPACK (IPACK Group) block or Continuous ACB with sham subcutaneous saline injection (No IPACK Group). IPACK Group received single injection of 20 mL 0.25% Ropivacaine. Postoperatively, all patients received a standardized multimodal analgesic regimen. The study followed a double-blinded format. Only the anesthesiologist performing the block was aware of randomization status. Following surgery, a blinded medical assessor recorded cumulative opioid consumption, average and worst pain scores, and gait distance. Results. 72 people were enrolled in the study and three withdrew. There were 35 people in the IPACK group and 34 in the NO IPACK group. There was no difference demographically between the groups. In the Post Anesthesia Care Unit (PACU), the average (P=0.0122) and worst (P=0.0168) pain scores at rest were statistically lower in the IPACK group. There was no difference in the pain scores during physical therapy. (P=0.2080) There was no difference in opioid consumption in the PACU (P=0.7928), at 8 hours (P=0.2867), 16 hours (P=0.2387), 24 hours (P=0.7456), or 30 hours (P=0.8029). There was no difference in pain scores on POD 1 in the AM (P=0.4597) or PM (P=0.6273), nor was there any difference in walking distance (P=0.5197). There was also no difference in length of stay in the PACU (P=0.9426) or hospital (P=0.2141) between the two groups. Discussion/Conclusion. Overall, pain was well controlled between the two groups. The IPACK group had lower pain scores at rest in the PACU, but this may not be clinically significant. The routine use of the IPACK is not supported by the results of this study. There may be use of the IPACK block as a rescue block or in patients whom have contraindications to our standard multimodal treatment regimen, or in patients with chronic pain or opioid dependence

Introduction The aim of the study was to investigate the incidence, in Australia, of popliteal artery injury during knee surgery; to assess the distance from the popliteal artery to the posterior tibia in flexion and extension; and to investigate the influence of major trauma or surgery on the anatomy. Methods A questionnaire was sent to Australian members of the ANZ Society of Vascular Surgeons. Duplex ultrasound studies were obtained through the Vascular Laboratory University of Melbourne. Studies in extension and 90° of flexion assessed the distance from the popliteal artery to the posterior tibia. Twelve persons with normal knees were assessed bilaterally. Eight patients with a posterior cruciate ligament deficient knee were assessed bilaterally. Seventy vascular surgeons responded documenting 115 popliteal artery injuries occurring during knee surgery. There were 69 lacerations, 27 thromboses, 13 AV fistula and 19 false aneurysms. In 12 normal people (24 knees) the popliteal artery was 5.5 mm (2.9 to 9.9) from the tibia in extension and 5.7 mm (2.9 to 10.0) in 90° of flexion. In ten of 24 knees the artery moved closer in flexion. In the eight posterior cruciate ligament deficient knees the artery was 4.7 mm (2.7 to 6.9) from the tibia in extension and 3.8 mm (2.6 to 4.5) at 90° of flexion. In all eight PCL knees the artery moved closer in flexion. In normal knees the popliteal artery may move closer to the tibia in flexion, the average distance being about 5.5 mm. Conclusions The popliteal artery is closer to the knee joint following trauma or surgery and specifically closer in flex-ion than in extension. Risks of injury are significant

Locking after total knee replacement is uncommon and is generally caused by the formation of fibrous tissue around the patella. We report an unusual cause of locking resulting from intermittent occlusion of the popliteal artery, which was tethered to cement at the posterior aspect of the tibial component

The February 2014 Knee Roundup. 360 . looks at: whether sham surgery is as good as arthroscopic meniscectomy; distraction in knee osteoarthritis; whether trans-tibial tunnel placement increases the risk of graft failure in ACL surgery; whether joint replacements prevent cardiac events; the size of the pulmonary embolism problem; tranexamic acid and knee replacement haemostasis; matching the demand for knee replacement and follow-up; predicting the length of stay after knee replacement; and popliteal artery injury in TKR

1. A case of traumatic aneurysm in the popliteal fossa after a lateral meniscectomy is described. 2. Relevant factors in the surgical anatomy of the inferior genicular artery are discussed. 3. The value and limitations of angiography of the popliteal artery are considered. 4. Treatment is governed by the degree of involvement of the popliteal artery. In the case described cure of the aneurysm was obtained by endo-aneurysmorrhaphy

Orthopaedic problems are common in patients with Ehlers-Danlos Syndrome (EDS). Articular hypermobility can be particularly disabling leading to instability in the appendicular skeleton. We present a case of an EDS patient presenting with knee pain and instability. It highlights important lessons to be learned when considering joint replacement in this patient group. A 51 year old lady with EDS underwent a posterior cruciate retaining total knee replacement for pain and instability. She dislocated her knee replacement three months post-operatively after a fall. Her knee was reduced at her local emergency department causing injury to the popliteal artery. She required urgent popliteal artery repair and fasciotomies. The common peroneal nerve was also irreversibly damaged by the dislocation. She has since had one further dislocation and is now awaiting revision surgery. When considering total knee replacement (TKR) in EDS, the patient must be warned of the inferior results compared to TKR for other causes. The increased risk of complications must be explained and a more constrained TKR design considered to address the inherent joint laxity. The potential consequences of a dislocated TKR can be disastrous and therefore relocation must be performed in a controlled environment in the operating theatre