Name: arthroscopic excision of posterior cruciate ligament cysts using a double posteromedial approach
Uploaded: 2023-10-20T14:50:00.000+00:00
Duration: 5 min 44 s
Description: Read this Scientific Article Protocol about Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts at JoVE.com

This research was supported by the Youth Science and Technology Project of the Department of Health of Hebei Province. (No.20201046).

The protocol follows the guidelines of the Ethics Committee of the Third Hospital of Hebei Medical University. Informed consent was obtained from the patients for including them and the data generated as a part of this study. Patients enrolled in this study were between the ages of 18-60. A total of eight patients were included in the study, five females and three males.
1. Preoperative preparation
<ol>
	<li>Use the following inclusion and exclusion criteria for enrolling patients in this study.
	<ol>
		<li>Use these inclusion criteria: Patients with a clear diagnosis of posterior cruciate ligament cyst by MRI of the knee; patients with significant knee pain, hyperextension pain, and other symptoms that may be caused by posterior cruciate ligament cyst or patients with combined meniscal injuries that require arthroscopic treatment; patients who have an interest in surgery because of the impact on their quality of life.</li>
		<li>Use these exclusion criteria: Patients with other serious medical conditions who cannot tolerate surgery; patients who refuse surgical treatment; patients with posterior cruciate ligament cyst diagnosed by MRI but without symptoms; patients with combined anterior cruciate ligament rupture or posterior cruciate ligament rupture.</li>
	</ol>
	</li>
	<li>Use general anesthesia or neuraxial anesthesia for all patients. Place the patient in the supine position on the surgical bed. Apply a tourniquet to the affected limb in the middle and upper part of the thigh for no more than 1 h. Disinfect the affected limb 2x with iodophor and lay the surgical sheet.</li>
</ol>
2. Establishment of arthroscopic approaches
<ol>
	<li>Use a blood-repellent belt to expel blood from the affected limb. Tighten the blood-repellent belt from the end of the limb to the proximal end. Make each lap overlap by 1/3. Do not insert soft tissue between each turn. Drain blood from the soft tissues of the operated limb. Inflate the tourniquet by applying 50 kPa pressure/force.</li>
	<li>Establish an anterolateral approach, 1 cm above the lateral knee line and 1 cm lateral to the patellar tendon margin. Make an incision of about 0.5 cm in size from the skin to the joint cavity using an 11G sharp blade.</li>
	<li>Establish an anteromedial approach, 1 cm above the medial knee articular line and 1 cm medial to the patellar tendon margin. Make an incision of about 0.5 cm in size from the skin to the joint cavity using an 11G sharp blade.</li>
	<li>Insert the arthroscope parallel to the tibial platform towards the intercondylar fossa in medial and lateral approaches, respectively. Explore the suprapatellar capsule, patellofemoral joint, medial trochanteric clearance, lateral trochanteric sulcus, anterior cruciate ligament, posterior cruciate ligament, medial meniscus, and lateral meniscus.</li>
	<li>Partially remove the injured meniscus or suture the injured meniscus. Remove the joint-free body. Treat all injuries within the joint.</li>
	<li>Establish a normal posteromedial approach as described below.
	<ol>
		<li>Flex the knee at 90&#176;. Insert the arthroscopy in the anteromedial approach to monitor the intercondylar fossa and place the switching rod in the anterolateral approach.</li>
		<li>Insert the exchange rod between the posterior cruciate ligament (PCL) and the medial femoral condyle into the posteromedial joint capsule under arthroscopic surveillance. There is usually a distinct sensation of slipping in and out.</li>
		<li>Rotate the lens to the medial posterior joint capsule. See the triangular area formed by the reverse fold of the joint capsule, the medial femoral condyle, and the medial meniscus.</li>
		<li>Turn off the operating room lights. Observe the translucent area of the posterior medial skin surface of the knee (Figure 2).</li>
		<li>Use a lumbar needle to assist positioning (Figure 3). Eccentric puncture into the joint capsule in the translucent area (usually 0.5-1 cm behind the posterior femoral condyle and proximal to the articular line).</li>
		<li>Make a small incision of about 0.5 cm in the skin using an 11G sharp blade. Insert a straight clamp into the joint capsule under arthroscopic surveillance. Establish a normal posteromedial approach.</li>
	</ol>
	</li>
	<li>Establish a high posteromedial approach as described below.
	<ol>
		<li>Insert the arthroscopy into the posteromedial approach. Insert the lumbar needle in the direction of the joint, 2-3 cm proximal to the posteromedial approach.</li>
		<li>Make the lumbar needle penetrate into the joint capsule in the triangular space of the medial posterior condyle, medial meniscus, and posterior joint capsule.</li>
		<li>Make a small incision in the skin. Insert a straight clamp into the joint capsule under arthroscopic surveillance. Establish a high posteromedial approach.</li>
	</ol>
	</li>
</ol>
3. Exposing and removing posterior cruciate ligament cysts
<ol>
	<li>Insert the arthroscopy in the high posteromedial approach. Insert the shaver in the normal posteromedial approach (Figure 4).</li>
	<li>Remove synovial tissue between the posterior cruciate ligament and the joint capsule using a shaver.</li>
	<li>Find the cyst, which is a translucent, raised synovial membrane around the posterior cruciate ligament (Figure 1C). Remove the cyst wall and see yellow and translucent fluid flowing out of the cyst wall, visualize compartment-like tissue in the cyst.</li>
	<li>Remove the posterior cyst wall completely. Avoid injury to the posterior cruciate ligament and posterior blood vessels and nerves and explore the posterior cruciate ligament without injury.</li>
	<li>Insert the arthroscopy in the anterolateral approach. See a portion of the cyst at the femoral terminus of the posterior cruciate ligament.</li>
	<li>Remove the anterior cyst wall and see yellow and translucent fluid flowing out of the cyst wall. Remove the cyst wall completely.</li>
	<li>Remove the synovial tissue in the V-shaped space between the anterior cruciate ligament and the posterior cruciate ligament. Probe the posterior cruciate ligament and check for damage to the posterior cruciate ligament.</li>
	<li>Insert the arthroscopy in the medial patellar approach. Check the V-shaped space between the anterior cruciate ligament and the posterior cruciate ligament for residual cysts.</li>
	<li>Insert the arthroscopy in the posteromedial approach. Check for residual cysts.</li>
</ol>
4. Closure of the incision
<ol>
	<li>Insert the arthroscopic sheath in the anterolateral approach. Squeeze the suprapatellar capsule and completely drain the intra-articular fluid. Check knee extension and flexion activities from 0&#176; to 120&#176;.</li>
	<li>Suture the incision with silk thread No. 4.</li>
</ol>
5. Postoperative rehabilitation
<ol>
	<li>Quadriceps exercise: Ask the patient to perform this exercise in the supine position. Straighten the affected limb, hook up the toes, slowly lift the leg upward to a height of about 15 cm on the heel, stay for 3 seconds, and then slowly lower it down.</li>
	<li>Joint release training: Ask the patients to perform this as they sit at the bedside and extend and flex the knee joint by themselves.</li>
	<li>Ask the patient to get out of bed on the second day after surgery and move appropriately, and gradually return to normal activities.</li>
	<li>Change the dressing every 3 days after surgery and remove the stitches 14 days after surgery.</li>
	<li>Ask the patient to perform non-confrontational activities such as jogging in the first month after surgery and resume normal activities in the third month after surgery.</li>
</ol>
6. Postoperative care and follow-up
<ol>
	<li>Ask the patient to lie flat without the pillow for 6 hours after surgery. The patient was hospitalized for approximately 3 days.</li>
	<li>At 3 months after surgery, check whether the patient&#39;s range of motion returns to normal and 12 months after surgery, perform an MRI examination of the affected knee combined with arthroscopy to check whether there is discomfort in the affected knee and whether the cyst has recurred.</li>
</ol>

Arthroscopic Double Posteromedial Approach for PCL Cyst Excision

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The authors declare that there are no conflicts of interest in this study.

Posterior cruciate ligament cyst is a rare disease. Knee ligament cysts are usually discovered during MRI or knee arthroscopy exams. The causes of knee ligament cyst formation are varied, including post-traumatic formation, synovial tissue hernia formation during embryogenesis, and mesenchymal stem cell proliferation and formation. Recently, trauma and tissue stimulation have been recognized by most experts2,7,14.
Most patients with posterior cruciate ligament cysts are asymptomatic and can be treated conservatively. In simple posterior cruciate ligament cysts, clinical symptoms are mostly related to the location or size of the cysts and are non-specific11,14. As the posterior ligament cyst enlarges, in addition to the pain symptoms of the knee joint, knee noose, hyperextension or hyperflexion pain, and reduced range of motion of the knee joint is observed8,11,14. The main methods of post-treatment of cruciate ligament cysts include arthroscopic resection and ultrasound-guided cyst puncture sac aspiration.
Jawish et al. found that cruciate ligament cysts treated with puncture and suction of cystic fluid showed relapse or poor results and required secondary posterior resection surgery or arthroscopic surgery15. The cyst shape is leaf-shaped or fusiform and may contain internal septations or be multilovary11,16,17 (Figure 1A,D). A cyst&#39;s formation requires an intact cyst wall in which the sac fluid is encased. However, simply extracting the fluid without removing the cyst wall results in the puncture site acting as a one-way valve. Due to the influence of a one-way valve or small puncture hole, the fluid in the cyst does not flow directly and freely between the joint cavity and the cyst cavity. This causes synovial fluid to accumulate in the cyst cavity, leading to the recurrence of the cyst after it is drained. This is the primary reason why cysts often reoccur after puncture and fluid suction. Arthroscopic surgery can completely remove the cyst wall, eliminate the cyst cavity, and cannot form a one-way flap, thereby avoiding synovial fluid from entering the cyst cavity in one direction, and the cyst will not recur8,13,18,19,20. Cyst fluid aspiration does not remove the cyst wall, only removes the synovial fluid in the cyst cavity, while arthroscopic surgery removes the cyst wall to release cystic fluid and can remove all the divided cyst walls under direct vision, completely preventing recurrence.
Some scholars have reported that arthroscopic cruciate ligament cysts after septal resection can completely remove cysts12,13. However, the addition of a posterolateral incision may increase the risk of injury to the common peroneal nerve, which may lead to foot dropping after surgery. Although the posterior cruciate ligament is not prone to degeneration because it receives both subchondral and synovial nutrients21,22,23,24,25, and the posterior cruciate ligament has vegetative posterior cruciate ligament vessels in the posterior synovial membrane, the septal approach may damage the blood vessels of the vegetative posterior cruciate ligament, and so the postoperative posterior cruciate ligament has poor blood supply, resulting in posterior cruciate ligament degeneration. Although the post-cruciate ligament cyst is treated with this surgical method, there is no recurrence after surgery, but the partial normal nutrient supply structure of the synovial membrane is damaged24.
Local anatomy around the posterior medial passage of the knee is relatively complex. According to our positioning method, when the knee joint is flexed by 90&#176;, the great saphenous vein and saphenous nerve are 2-3 cm anterior to it. The goosefoot tendon part is distal to its distal end, and the channel pierces part of the sartorius tendon above the gracilis tendon 0.5-1 cm. After the skin is poked, a slight peel and entry into the joint capsule using straight forceps bluntly minimizes collateral damage to the above structures. Since important vascular nerve structures are anterior or posterior to the high posteromedial approach, the high posteromedial approach does not increase the risk of vascular nerve injury. The double posteromedial approach removes the cyst wall under direct vision, does not destroy the posterior septal synovial tissue, preserves the blood vessels of the postoperative posterior cruciate ligament, and retains sufficient nutritional support for the recovery of the postoperative posterior cruciate ligament.
In patients with posterior cruciate ligament cysts of the knee, the main cyst portion is mostly behind the posterior cruciate ligament. In 3 out of 4 patients, the major cyst part originates posteriorly behind the posterior cruciate ligament. A double posteromedial approach was added, arthroscopic observation was inserted into the high posteromedial approach, and a shaver was inserted into the conventional posteromedial approach to remove the cyst. It has the advantages of easy observation and operation for the excision of the posterior cruciate ligament&#39;s posterior cyst.
In our surgical approach, the establishment of a double-posteromedial approach is the most critical step. When the normal posteromedial approach is established, patients often experience narrowing of the intercondylar fossa, which makes it difficult for the exchange rod to pass through the anterolateral approach through the intercondylar fossa to the posteromedial compartment, so we cannot establish the posteromedial approach under arthroscopic supervision. In this case, in patients with severe intercondylar fossa stenosis, we need to have the intercondylar fossa formed before inserting the exchange rod. For patients with relatively narrow intercondylar fossa, we can add the anterior median approach, through which an exchange rod is inserted through the intercondylar fossa into the posteromedial compartment. The establishment of a high posteromedial approach is also very important. If the high posteromedial approach is too close to the normal posteromedial approach, arthroscopy and shaver strike can have an impact on the operation. If the posteromedial approach is anterior or posterior, we may not completely remove the cyst because of an unclear visual field when we remove the cyst. Therefore, it is important to establish a suitable position for a double posteromedial approach under arthroscopic monitoring.
Our surgical method also has its drawbacks, and establishing a double posteromedial approach carries the risk of damaging the saphenous vein and saphenous nerve. Although the approach is a safe distance from the saphenous vein and saphenous nerve, since we need to obtain the best cyst field of view and operating space in the posteromedial approach, we need to adjust the optimal position of the posteromedial approach according to different cyst locations, which may increase the risk of injury to the saphenous vein and saphenous nerve. Due to the limited space of the posteromedial compartment, the establishment of two suitable positions of double approach on the basis of limited space increases the technical difficulty and requires higher surgical techniques of the operator. The arthroscopic double posteromedial approach is a safe and effective technique for PCL cyst resection. For the removal of dorsal cysts of the posterior cruciate ligament, especially those near the tibial end or compartmentalized cysts, this surgical approach offers significant advantages.

Joint cysts are cystic lesions, and the cyst fluid is a transparent jelly-like fluid that can be found in the ligament, meniscus, synovial membrane, and other parts of the knee joint1,2. High mechanical stress can easily lead to cyst formation, which is why cysts are most common in the knee joint3,4, and Baker&#39;s cysts are the most common type of cysts5. Cruciate ligament cysts of the knee are rare, occurring incidentally in 0.2% to 1.3% of cases scanned using knee magnetic resonance imaging (MRI) and in 0.6% of patients tested using knee arthroscopy6,7. Posterior cruciate ligament cysts are rarer, with Brown and Dandy reporting that after performing knee arthroscopy on 6,500 patients, they found only 35 ligament cysts and only 6 from the posterior cruciate ligament5. Knee ligament cysts can occur regardless of sex or age but are more common in men aged 20 years to 40 years4,8.
The cause of cruciate ligament cysts is unknown. For the non-invasive diagnosis of knee ligament cysts, MRI can clearly show the relationship between the size and position of the cyst and is the most accurate diagnostic method4,6,9,10. Arthroscopic removal of cysts is the most effective and recommended treatment method4,6,9,10. Arthroscopy can see the cyst site directly and completely remove the cyst wall, the recurrence rate is extremely low, and the patient recovers quickly after surgery7,9,10. Posterior cruciate ligament cysts are mostly lobulated or multiloculated, most of which are located mainly behind the posterior cruciate ligament, and in 12.5% of patients, the cyst is mainly located anterior to the posterior cruciate ligament11 (Figure 1A,B).
Many treatments can be used to treat posterior cruciate ligament cysts, such as ultrasound and computed tomography-guided joint paracentesis. However, several studies have shown that there is a potentially higher risk of recurrence because of which these procedures do not remove the cyst walls12. Arthroscopic removal of cysts is the gold standard for the treatment of posterior cruciate ligament cysts. Arthroscopic surgery can completely remove the cyst wall, but it&#39;s hard to remove dorsal cruciate ligament cysts by the anterior approach alone. Abreu et al.12 introduced an approach to the arthroscopic excision of PCL cysts using a trans-septal portal, and it&#39;s safe and effective. Tsai et al.13 reported that the trans-septal approach to the resection of posterior cruciate ligament cysts was successful in 15 patients, and there was no recurrence. The trans-septal approach requires the addition of a posterolateral approach, so it increases the risk of damaging the common peroneal nerve and popliteal neurovascular bundle. To avoid these risks, we present a surgical approach to treat posterior cruciate ligament cysts by an arthroscopic double posteromedial approach. Our approach does not require an additional posterolateral approach; there is no risk of injuring the common peroneal nerve. We use the double posteromedial approach, which keeps the entire surgical process on the medial side of the posterior septal, thus reducing the possibility of damaging the popliteal neurovascular bundle. The technique produces the same results while being safer than the trans-septal approach. This surgical approach is particularly suitable for the removal of cysts located on the dorsal side of the posterior cruciate ligament. The surgical approach is more advantageous if the cyst is compartmentalized or close to the tibial end.

<table><tbody><tr><td>Arthroscopic sheath&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>72200829</td><td>6mm</td></tr><tr><td>Arthroscopy</td><td>smith&amp;amp;nephew</td><td>72202087</td><td>30 mm x 4 mm</td></tr><tr><td>Beam guide&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>72204925</td><td>5 mm x 3.6 m</td></tr><tr><td>Beam guide-arthroscopy end connector&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>2143</td><td></td></tr><tr><td>Beam guide-panel connector&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>2147</td><td></td></tr><tr><td>Blood-repellent belt</td><td>selani</td><td>tpe15100</td><td>15 cm x 1 m</td></tr><tr><td>Blunt puncture cone&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>4356</td><td>4 mm</td></tr><tr><td>Camera&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>72200561</td><td>NTSC/PAL</td></tr><tr><td>Coupler&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>72200315</td><td></td></tr><tr><td>DYONICS POWER II</td><td>smith&amp;amp;nephew</td><td>72200873</td><td>100-24VAC, 50/60Hz</td></tr><tr><td>DYONICS POWERMAX ELITE</td><td>smith&amp;amp;nephew</td><td>72200616</td><td></td></tr><tr><td>Endoscopic camera system</td><td>smith&amp;amp;nephew</td><td>72201919</td><td>560P NTSC/PAL</td></tr><tr><td>HD monitor&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>&amp;nbsp;LB500031</td><td>27 inch&amp;nbsp;</td></tr><tr><td>Hook probe&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>3312</td><td></td></tr><tr><td>Incisor plus platinum shaver&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>72202531</td><td>&amp;nbsp;4.5 mm</td></tr><tr><td>Lumbar needle&amp;nbsp; AN-E/S&amp;nbsp;&lt;img alt=&quot;Equation 1&quot; src=&quot;/files/ftp_upload/65620/65620eq01.jpg&quot; style=&quot;margin: auto;&quot;/&gt;</td><td>tuoren</td><td>AN-E/S&amp;nbsp;&lt;img alt=&quot;Equation 1&quot; src=&quot;/files/ftp_upload/65620/65620eq01.jpg&quot; style=&quot;margin: auto;&quot;/&gt;</td><td>1.6 mm x 80 mm</td></tr><tr><td>Micropunch,teardrop,left&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>7207602</td><td></td></tr><tr><td>Micropunch,teardrop,right&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>7207601</td><td></td></tr><tr><td>Micropunch,teardrop,straight&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>7207600</td><td></td></tr><tr><td>Pitbull Jr. Grasper&amp;nbsp;&amp;nbsp;</td><td>smith&amp;amp;nephew</td><td>14845</td><td></td></tr></tbody></table>

arthroscopic excision of posterior cruciate ligament cysts using a double posteromedial approach

Cruciate ligament cysts of the knee are a rare condition. Posterior cruciate ligament cysts of the knee are less common than anterior cruciate ligament cysts. In patients with asymptomatic isolated cruciate ligament cysts of the knee, conservative treatment is recommended. Symptomatic cruciate ligament cysts of the knee are mostly manifested as knee hyperflexion pain, straightening pain, knee discomfort after standing for a long time or walking for a long time, etc., which seriously affects the quality of life, surgical treatment can be performed. The surgical treatments can be divided into ultrasound-guided cyst puncture and fluid extraction procedure and arthroscopic cystectomy. Cysts are mostly lobulated with a multi-layer cyst wall, cyst fluid extraction does not remove the cyst wall completely but simply extracts cyst fluid, leading to a high recurrence rate. Arthroscopic surgery can completely remove the cyst wall with little trauma, a low recurrence rate, and fast postoperative recovery, so arthroscopic resection is the most common and preferred method of treatment. Since posterior cruciate ligament cysts mostly occur posterior to the ligament, we remove the cyst wall by adding a double posteromedial approach to the knee joint, and the cyst wall is removed under direct vision, which is simple to operate, the cyst wall is completely cleared, the trauma is small, the postoperative recovery is fast, and there is no recurrence. Here, 8 posterior cruciate ligament cysts were removed with complete postoperative symptom relief, no surgical complications, and no recurrence at 1-year follow-up.

All eight patients were successfully operated on without any complications. Seven of the 8 patients had isolated posterior cruciate ligament cysts, and 1 patient had medial meniscal injury. The main symptoms of all patients before surgery are knee hyperflexion pain, inability to squat freely, pain, and discomfort in the back of the knee after standing for a long time or walking for a long time. After surgery, all symptoms were relieved and disappeared (Table 1).
Of the 7 patients with simple posterior cruciate ligament cysts, 1 year after surgery, no special discomfort was found. The postoperative knee range of motion significantly improved compared with the preoperative period, the patient could squat freely, and no special discomfort in the knee joint after standing for a long time or walking for a long time was found (Table 2). For the single patient with medial meniscal injury, a partial resection of the medial meniscus and 2&#176;-3&#176; degeneration of medial cartilage was performed during surgery. The follow-up 1 year after surgery found occasional mild knee joint discomfort, the knee range of motion significantly improved compared with the preoperative period, and the patient could squat freely. Mild pain on the inside of the knee after prolonged walking is considered to be a symptom caused by mild osteoarthritis. Repeat knee MRI shows mild cartilage degeneration. Knee discomfort was not associated with a posterior cruciate ligament cyst.
Posterior cruciate ligament cysts were seen on preoperative MRI in all patients (Figure 1A,D). All patients had an MRI 1 year after surgery and no recurrence was found (Figure 1B,E). In all patients, cysts can be seen during surgery (Figure 1C), and the cyst wall was completely removed during surgery, which means the success of all surgeries (Figure 1F).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/65620/65620fig01.jpg" /> 
Figure 1: Preoperative and postoperative MRI and arthroscopic images of cysts. (A) Sagittal MRI of the knee: posterior cyst of the posterior cruciate ligament (indicated by the red arrow). (B) Posterior cruciate ligament cyst recurrence was not seen on sagittal MRI of the knee 1 year after surgery (indicated by red arrow). (C) Posteromedial approach, arthroscopic view of posterior cruciate ligament cyst (indicated by red arrow). (D) MRI of the coronal position of the knee: anterior cyst of the posterior cruciate ligament (indicated by the red arrow); posterior cruciate ligament cyst with compartment-like structures visible within the cyst. (E) No recurrence of posterior cruciate ligament cyst on knee coronal MRI 1 year after surgery (indicated by red arrow). (F) Arthroscopic resection of posterior cruciate ligament cyst wall (indicated by red arrow). <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/65620/65620fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/65620/65620fig02.jpg" /> 
Figure 2: Light transmission phenomena on the surface of the skin. Flex the knee at 90&#176; and insert the arthroscopy through the anterolateral approach into the posteromedial joint capsule between the PCL and the medial femoral condyle, and light transmission can be observed on the posteromedial skin surface of the knee. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/65620/65620fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/65620/65620fig03.jpg" /> 
Figure 3: Establishing a posteromedial approach. At 0.5-1 cm each behind the posterior femoral condyle and the proximal end of the joint line, touch the needlepoint of the posteromedial approach on the posteromedial skin of the joint and puncture the lumbar needle toward the posteromedial capsule, and there is water flowing out. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/65620/65620fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/65620/65620fig04.jpg" /> 
Figure 4: The position of the arthroscope and shaver in the double posteromedial approach. Use the same method to create an additional posteromedial approach 2-3 cm proximal to the posteromedial approach, forming a double posteromedial approach. The arthroscopy and shaver are placed, respectively. <a href="https://www-jove-com.remotexs.ntu.edu.sg/files/ftp_upload/65620/65620fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td></td>
			<td>Knee hyperflexion pain</td>
			<td>Inability to squat freely</td>
			<td>Pain and discomfort in the back of the knee</td>
		</tr>
		<tr>
			<td>Pre-surgery</td>
			<td>8 out of 8</td>
			<td>8 out of 8</td>
			<td>8 out of 8</td>
		</tr>
		<tr>
			<td>Post-surgery</td>
			<td>0 out of 8</td>
			<td>0 out of 8</td>
			<td>0 out of 8</td>
		</tr>
	</tbody>
</table>
Table 1: Comparison of the symptoms of pre-surgery and post-surgery. The patient&#39;s symptoms improved significantly after surgery.
<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Independent posterior cruciate ligament cyst</td>
			<td>posterior cruciate ligament cysts with medial meniscal injury</td>
			<td>Recovery time</td>
			<td>relapse</td>
		</tr>
		<tr>
			<td>7 out of 8</td>
			<td>1 out of 8</td>
			<td>3 months</td>
			<td>0 out of 8</td>
		</tr>
	</tbody>
</table>
Table 2: Types of the patients. None of the patients had any recurrence after surgery.

Read this Scientific Article Protocol about Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts at JoVE.com

Author Spotlight: Double Posteromedial Approach for Treating Posterior Cruciate Ligament Cysts

We present a surgical approach to treat posterior cruciate ligament cysts by an arthroscopic double posteromedial approach.

Arthroscopic Excision of Posterior Cruciate Ligament Cysts Using a Double Posteromedial Approach

Cruciate ligament cysts of the knee are a rare condition. Posterior cruciate ligament cysts of the knee are less common than anterior cruciate ligament ...

arthroscopic-excision-posterior-cruciate-ligament-cysts-using-double

Nanyang Technological University

Research

JoVE Journal

Medicine

472 Views.  The Third Hospital of Hebei Medical University. Kruisbandcysten in de knie, vooral de achterste, komen niet vaak voor. Arthroscopische chirurgie is de voorkeursbehandeling, vanwege minimaal trauma, laag recidief, en snel herstel. Waardoor het de meest voorkomende keuze is voor volledige verwijdering van cysten.Achterste kruisbandcysten die zich achter het ligament bevinden, worden tijdens arthroscopische chirurgie behandeld met een dubbele posteromediale benadering. Deze aanpak is voor het eerst visueel ontwikkeld voor volledige ver...

Video: Auteur in de schijnwerpers: dubbele posteromediale benadering voor de behandeling van cysten in de achterste kruisband

A Simplified Technique for In situ Excision of Cornea and Evisceration of Retinal Tissue from Human Ocular Globe

Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina. The ocular globe consists of the cornea, the sclera, the vitreous body, the lens, the iris, the retina, the choroid, muscles etc (Suppl. Figure 1). When a patient is suffering from corneal damage, the cornea needs to be removed and a healthy one must be transplanted by keratoplastic surgeries. Genetic disorders or defects in retinal function can compromise vision. Human ocular globes can be used for various surgical procedures such as eye banking, transplantation of human cornea or sclera and research on ocular tissues. However, there is little information available on human corneal and retinal excision, probably due to the limited accessibility to human tissues. Most of the studies describing similar procedures are performed on animal models. Research scientists rely on the availability of properly dissected and well-conserved ocular tissues in order to extend the knowledge on human eye development, homeostasis and function. As we receive high amount of ocular globes out of which approximately 40% (Table 1) of them are used for research purposes, we are able to perform huge amount of experiments on these tissues, defining techniques to excise and preserve them regularly.
The cornea is an avascular tissue which enables the transmission of light onto the retina and for this purpose should always maintain a good degree of transparency. Within the cornea, the limbus region, which is a reservoir of the stem cells, helps the reconstruction of epithelial cells and restricts the overgrowth of the conjunctiva maintaining corneal transparency and clarity. The size and thickness of the cornea are critical for clear vision, as changes in either of them could lead to distracted, unclear vision. The cornea comprises of 5 layers; a) epithelium, b) Bowman's layer, c) stroma, d) Descemet's membrane and e) endothelium. All layers should function properly to ensure clear vision4,5,6. The choroid is the intermediate tunic between the sclera and retina, bounded on the interior by the Bruch's membrane and is responsible for blood flow in the eye. The choroid also helps to regulate the temperature and supplies nourishment to the outer layers of the retina5,6. The retina is a layer of nervous tissue that covers the back of the ocular globe (Suppl. Figure 1) and consists of two parts: a photoreceptive part and a non-receptive part. The retina helps to receive the light from the cornea and lens and converts it into the chemical energy eventually transmitted to the brain with help of the optic nerve5,6.
The aim of this paper is to provide a protocol for the dissection of corneal and retinal tissues from human ocular globes. Avoiding cross-contamination with adjacent tissues and preserving RNA integrity is of fundamental importance as such tissues are indispensable for research purposes aimed at (i) characterizing the transcriptome of the ocular tissues, (ii) isolating stem cells for regenerative medicine projects, and (iii) evaluating histological differences between tissues from normal/affected subjects. In this paper we describe the technique we currently use to remove the cornea, the choroid and retinal tissues from an ocular globe. Here we provide a detailed protocol for the dissection of the human ocular globe and the excision of corneal and retinal tissues. The accompanying video will help researchers to learn an appropriate technique for the retrieval of precious human tissues which are difficult to find regularly.

A Simplified Technique for In situ Excision of Cornea and Evisceration of Retinal Tissue from Human Ocular Globe

The paper describes a simplified technique to excise corneal and to eviscerate retinal tissues from the ocular globe of human cadaveric donors. The technique described here will help to excise good quality tissues to be used for transplantation, surgical or research purposes without damaging other tissues of the ocular globe.

Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the ...

Surgical Retrieval, Isolation and In vitro Expansion of Human Anterior Cruciate Ligament-derived Cells for Tissue Engineering Applications

Injury to the ACL is a commonly encountered problem in active individuals. Even partial tears of this intra-articular knee ligament lead to biomechanical deficiencies that impair function and stability. Current options for the treatment of partial ACL tears range from nonoperative, conservative management to multiple surgical options, such as: thermal modification, single-bundle repair, complete reconstruction, and reconstruction of the damaged portion of the native ligament. Few studies, if any, have demonstrated any single method for management to be consistently superior, and in many cases patients continue to demonstrate persistent instability and other comorbidities.
The goal of this study is to identify a potential cell source for utilization in the development of a tissue engineered patch that could be implemented in the repair of a partially torn ACL. A novel protocol was developed for the expansion of cells derived from patients undergoing ACL reconstruction. To isolate the cells, minced hACL tissue obtained during ACL reconstruction was digested in a Collagenase solution. Expansion was performed using DMEM/F12 medium supplemented with 10% fetal bovine serum (FBS) and 1% penicillin/streptomycin (P/S). The cells were then stored at -80 &#186;C or in liquid nitrogen in a freezing medium consisting of DMSO, FBS and the expansion medium. After thawing, the hACL derived cells were then seeded onto a tissue engineered scaffold, PLAGA (Poly lactic-co-glycolic acid) and control Tissue culture polystyrene (TCPS). After 7 days, SEM was performed to compare cellular adhesion to the PLAGA versus the control TCPS. Cellular morphology was evaluated using immunofluorescence staining. SEM (Scanning Electron Microscope) micrographs demonstrated that cells grew and adhered on both PLAGA and TCPS surfaces and were confluent over the entire surfaces by day 7. Immunofluorescence staining showed normal, non-stressed morphological patterns on both surfaces. This technique is promising for applications in ACL regeneration and reconstruction.

Surgical Retrieval, Isolation and In vitro Expansion of Human Anterior Cruciate Ligament-derived Cells for Tissue Engineering Applications

For future applications as a patch to repair partial tears of the Anterior Cruciate Ligament (ACL), human ACL derived cells were isolated from tissue obtained during reconstructive procedures, expanded in vitro and grown on tissue engineered scaffolds. Cellular adhesion and morphology was then performed to confirm biocompatibility on scaffold surface.

Injury to the ACL is a commonly encountered problem in active individuals. Even partial tears of this intra-articular knee ligament lead to biomechanical ...

Bioengineering

Athymic Rat Model for Evaluation of Engineered Anterior Cruciate Ligament Grafts

Anterior cruciate ligament (ACL) rupture is a common ligamentous injury that often requires surgery because the ACL does not heal well without intervention. Current treatment strategies include ligament reconstruction with either autograft or allograft, which each have their associated limitations. Thus, there is interest in designing a tissue-engineered graft for use in ACL reconstruction. We describe the fabrication of an electrospun polymer graft for use in ACL tissue engineering. This polycaprolactone graft is biocompatible, biodegradable, porous, and is comprised of aligned fibers. Because an animal model is necessary to evaluate such a graft, this paper describes an intra-articular athymic rat model of ACL reconstruction that can be used to evaluate engineered grafts, including those seeded with xenogeneic cells. Representative histology and biomechanical testing results at 16 weeks postoperatively are presented, with grafts tested immediately post-implantation and contralateral native ACLs serving as controls. The present study provides a reproducible animal model with which to evaluate tissue engineered ACL grafts, and demonstrates the potential of a regenerative medicine approach to treatment of ACL rupture.

Animal models are important tools for the evaluation of tissue-engineered grafts. This paper presents the protocol for preparing an electrospun biodegradable polymer graft for use in anterior cruciate ligament tissue engineering, as well as a surgical protocol for implantation in a rat model.

Anterior cruciate ligament (ACL) rupture is a common ligamentous injury that often requires surgery because the ACL does not heal well without ...

A Possible Zebrafish Model of Polycystic Kidney Disease: Knockdown of wnt5a Causes Cysts in Zebrafish Kidneys

Polycystic kidney disease (PKD) is one of the most common causes of end-stage kidney disease, a devastating disease for which there is no cure. The molecular mechanisms leading to cyst formation in PKD remain somewhat unclear, but many genes are thought to be involved. Wnt5a is a non-canonical glycoprotein that regulates a wide range of developmental processes. Wnt5a works through the planar cell polarity (PCP) pathway that regulates oriented cell division during renal tubular cell elongation. Defects of the PCP pathway have been found to cause kidney cyst formation. Our paper describes a method for developing a zebrafish cystic kidney disease model by knockdown of the wnt5a gene with wnt5a antisense morpholino (MO) oligonucleotides. Tg(wt1b:GFP) transgenic zebrafish were used to visualize kidney structure and kidney cysts following wnt5a knockdown. Two distinct antisense MOs (AUG - and splice-site) were used and both resulted in curly tail down phenotype and cyst formation after wnt5a knockdown. Injection of mouse Wnt5a mRNA, resistant to the MOs due to a difference in primary base pair structure, rescued the abnormal phenotype, demonstrating that the phenotype was not due to &#8220;off-target&#8221; effects of the morpholino. This work supports the validity of using a zebrafish model to study wnt5a function in the kidney.

A Possible Zebrafish Model of Polycystic Kidney Disease: Knockdown of wnt5a Causes Cysts in Zebrafish Kidneys

We describe a method of generating a possible zebrafish model of polycystic kidney disease. We used Tg(wt1b:GFP) fish to visualize kidney structure. Knockdown of wnt5a was by morpholino injection. Pronephric cyst formation after wnt5a knockdown was observed in this GFP transgenic zebrafish.

Polycystic kidney disease (PKD) is one of the most common causes of end-stage kidney disease, a devastating disease for which there is no cure. The ...

Isolation and Excision of Murine Aorta; A Versatile Technique in the Study of Cardiovascular Disease

Cardiovascular disease is a broad term describing disease of the heart and/or blood vessels. The main blood vessel supplying the body with oxygenated blood is the aorta. The aorta may become affected in diseases such as atherosclerosis and aneurysm. Researchers investigating these diseases would benefit from direct observation of the aorta to characterize disease progression as well as to evaluate efficacy of potential therapeutics. The goal of this protocol is to describe proper isolation and excision of the aorta to aid investigators researching cardiovascular disease. Isolation and excision of the aorta allows investigators to look at gross morphometric changes as wells as allowing them to preserve and stain the tissue to look at histologic changes if desired. The aorta may be used for molecular studies to evaluate protein and gene expression to discover targets of interest and mechanisms of action. This technique is superior to imaging modalities as they have inherent limitations in technology and cost. Additionally, primary isolated cells from a freshly isolated and excised aorta can allowing researchers to perform further in situ and in vitro assays. The isolation and excision of the aorta has the limitation of having to sacrifice the animal however, in this case the benefits outweigh the harm as it is the most versatile technique in the study of aortic disease.

Pathology of the aorta can lead to severe morbidity and mortality, therefore research of disease progression and potential therapies is warranted. Here, we present a protocol to isolate and excise the murine aorta to aid researchers in their investigation of cardiovascular disease.

Cardiovascular disease is a broad term describing disease of the heart and/or blood vessels. The main blood vessel supplying the body with oxygenated ...

Localization, Identification, and Excision of Murine Adipose Depots

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 reached a staggering sum of $190.2 billion in direct medical costs alone. Obesity is a major risk factor for a wide host of diseases. Historically, little was known regarding adipose and its major and essential functions in the body. Brown and white adipose are the two main types of adipose but current literature has identified a new type of fat called brite or beige adipose. Research has shown that adipose depots have specific metabolic profiles and certain depots allow for a propensity for obesity and other related disorders. The goal of this protocol is to provide researchers the capacity to identify and excise adipose depots that will allow for the analysis of different factorial effects on adipose; as well as the beneficial or detrimental role adipose plays in disease and overall health. Isolation and excision of adipose depots allows investigators to look at gross morphological changes as well as histological changes. The adipose isolated can also be used for molecular studies to evaluate transcriptional and translational change or for in vitro experimentation to discover targets of interest and mechanisms of action. This technique is superior to other published techniques due to the design allowing for isolation of multiple depots with simplicity and minimal contamination.

Due to the drastic and negative connection between obesity and other comorbidities, research on the role adipose plays in disease and overall health is warranted. We present a protocol for the isolation and excision of adipose depots allowing for the study of adipose using in situ and in vitro methods.

Obesity has increased dramatically in the last few decades and affects over one third of the adult US population. The economic effect of obesity in 2005 ...

Autologous Microfractured and Purified Adipose Tissue for Arthroscopic Management of Osteochondral Lesions of the Talus

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several studies have focused their attention on mesenchymal stem cells derived from adipose tissue. Adipose-derived stem cells (ADSCs) exhibit morphological characteristics and properties similar to other mesenchymal cells, and are able to differentiate into several cellular lines. Moreover, these cells are also widely available in the subcutaneous tissue, representing 10 - 30% of the normal body weight, with a concentration of 5,000 cells per gram of tissue.
In the presented technique, the first step involves harvesting ADSCs from the abdomen and a process of microfracture and purification; next, the surgical procedure is performed entirely arthroscopically, with less soft tissue dissection, better joint visualization, and a faster recovery compared with standard open procedures. Arthroscopy is characterized by a first phase in which the lesion is identified, isolated, and prepared with microperforations; the second step, performed dry, involves injection of adipose tissue at the level of the lesion.
Between January 2016 and September 2016, four patients underwent arthroscopic treatment of osteochondral lesion of the talus with microfractured and purified adipose tissue. All patients reported clinical improvement six months after surgery with no reported complications. Functional scores at the latest follow-up are encouraging and confirm that the technique provides reliable pain relief and improvements in patients with osteochondral lesion of the talus.

The aim of this study is to report a protocol for the arthroscopic treatment of osteochondral lesions of the talus using microfractured and purified adipose-derived stem cells.

In recent years, regenerative techniques have been increasingly studied and used to treat osteochondral lesions of the talus. In particular, several ...

An Effective Surgical Strategy for Anteromedial Osteoarthritis of the Knee with Simultaneous Popliteal Cysts Drainage

Unicompartmental knee arthroplasty (UKA) is an established treatment option for anteromedial osteoarthritis, and popliteal cysts are a common finding in the knee among patients with chronic osteoarthritis pain. The two are so closely related that popliteal cysts are commonly discovered during the unicompartmental knee arthroplasty preoperative examination. However, only a few reports exist on the management and outcome of popliteal cysts in the patients receiving UKA for knee osteoarthritis (OA) and popliteal cysts. As such, it is crucial to evaluate different treatment strategies and their management of popliteal cysts. In this paper, we evaluate a surgical strategy for patients with knee anteromedial osteoarthritis and symptomatic popliteal cysts. These patients were treated with UKA and internal drainage of the popliteal cyst. The results shown here, spanning 1-year post-operation follow-up, demonstrated that UKA and internal drainage is an effective surgical protocol for treating anteromedial osteoarthritis with symptomatic popliteal cysts.

Popliteal cysts are frequently found during the pre-operative examination of patients with osteoarthritis being prepared for the unicompartmental knee arthroplasty. These symptomatic cysts usually require treatment. To do this, a unicompartmental knee arthroplasty was performed with internal drainage of the popliteal cyst under the same anesthetic.

Unicompartmental knee arthroplasty (UKA) is an established treatment option for anteromedial osteoarthritis, and popliteal cysts are a common finding in ...

Arthroscopic Repair of Medial Meniscus Posterior Root Tear with Adjustable Titanium Plate Fixation

Medial meniscus injury is one of the most prevalent knee disorders, with posterior root tears occurring in approximately 10% to 21% of affected individuals. A posterior root tear disrupts the meniscus's continuous annular structure, compromising its ability to absorb pressure and protect the knee's articular cartilage. If left untreated, this can result in increased stress on the cartilage, leading to conditions such as varus deformity and accelerated joint degeneration. Partial removal (resection) of the medial meniscus further exacerbates these issues, often leading to quicker joint deterioration. Repairing medial meniscus posterior root tears (MMPRTs) plays a crucial role in restoring the meniscus's structural integrity and improving knee biomechanics. Studies have shown that compared to partial medial meniscectomy or conservative treatments, repairing MMPRTs enhances clinical outcomes and significantly delays the onset of arthritis. This article details a surgical procedure that uses a single-suture, double-loop, adjustable titanium plate fixation technique under arthroscopy for effective MMPRT repair.

This article describes a surgical approach to repairing a medial meniscus posterior root tear (MMPRT) using a single-suture, double-loop, adjustable titanium plate internal fixation under arthroscopy.

Arthroscopic Excision of Posterior Cruciate Ligament Cysts Using a Double Posteromedial Approach

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