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 pa...

Arthroscopic Double Posteromedial Approach for PCL Cyst Excision

<ol>
	<li>Deutsch, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Symptomatic+intraarticular+ganglia+of+the+cruciate+ligaments+of+the+knee.">Symptomatic intraarticular ganglia of the cruciate ligaments of the knee.</a> Arthroscopy. 10 (2), 219-223 (1994).</li><li>Zantop, T., Rusch, A., Hassenpflug, J., Petersen, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-articular+ganglion+cysts+of+the+cruciate+ligaments:+Case+report+and+review+of+the+literature.">Intra-articular ganglion cysts of the cruciate ligaments: Case report and review of the literature.</a> Arch Orthop Trauma Surg. 123 (4), 195-198 (2003).</li><li>Garcia, A., Hodler, J., Vaughn, L., Haghighi, P., Resnick, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Case+report+667.+Intraarticular+ganglion+arising+from+the+posterior+cruciate-ligament.">Case report 667. Intraarticular ganglion arising from the posterior cruciate-ligament.</a> Skeletal Radiol. 20 (5), 373-375 (1991).</li><li>Garc&#237;a-Alvarez, F., Garc&#237;a-Pequerul, J. M., Avila, J. L., Sainz, J. M., Castiella, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cysts+associated+with+cruciate+ligaments+of+the+knee:+A+possible+cause+of+recurrent+knee+pain.">Ganglion cysts associated with cruciate ligaments of the knee: A possible cause of recurrent knee pain.</a> Acta Orthop Belg. 66 (5), 490-494 (2000).</li><li>Brown, M. F., Dandy, D. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-articular+ganglia+in+the+knee.">Intra-articular ganglia in the knee.</a> Arthroscopy. 6 (4), 322-323 (1990).</li><li>Kim, M. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-articular+ganglion+cysts+of+the+knee:+Clinical+and+MR+imaging+features.">Intra-articular ganglion cysts of the knee: Clinical and MR imaging features.</a> Eur Radiol. 11 (5), 834-840 (2001).</li><li>Kim, R. S., Kim, K. T., Lee, J. Y., Lee, K. Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cysts+of+the+posterior+cruciate+ligament.">Ganglion cysts of the posterior cruciate ligament.</a> Arthroscopy. 19 (6), e36-e40 (2003).</li><li>Shetty, G. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cysts+of+the+posterior+cruciate+ligament.">Ganglion cysts of the posterior cruciate ligament.</a> The Knee. 15 (4), 325-329 (2008).</li><li>DeFriend, D. E., Schranz, P. J., Silver, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultrasound-guided+aspiration+of+posterior+cruciate+ligament+ganglion+cysts.">Ultrasound-guided aspiration of posterior cruciate ligament ganglion cysts.</a> Skeletal Radiol. 30 (7), 411-414 (2001).</li><li>Krudwig, W. K., Schulte, K. K., Heinemann, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intra-articular+ganglion+cysts+of+the+knee+joint:+A+report+of+85+cases+and+review+of+the+literature.">Intra-articular ganglion cysts of the knee joint: A report of 85 cases and review of the literature.</a> Knee Surg Sports Traumatol Arthrosc. 12 (2), 123-129 (2004).</li><li>Seki, K., Mine, T., Tanaka, H., Isida, Y., Taguchi, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Locked+knee+caused+by+intraarticular+ganglion.">Locked knee caused by intraarticular ganglion.</a> Knee Surg Sports Traumatol Arthrosc. 14 (9), 859-861 (2006).</li><li>Abreu, F. G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Excision+of+a+posterior+cruciate+ligament+cyst+using+an+arthroscopic+trans-septal+approach.">Excision of a posterior cruciate ligament cyst using an arthroscopic trans-septal approach.</a> Arthrosc Tech. 9 (4), e581-e585 (2020).</li><li>Tsai, T. Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Arthroscopic+excision+of+ganglion+cysts+of+the+posterior+cruciate+ligaments+using+posterior+trans-septal+portal.">Arthroscopic excision of ganglion cysts of the posterior cruciate ligaments using posterior trans-septal portal.</a> Arthroscopy. 28 (1), 95-99 (2012).</li><li>Boushnak, M. n. O., Moussa, M. K., Abed Ali, A., Alayane, A., Bayoud, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+uncommon+finding+of+posterior+cruciate+ligament+intrasubstance+cyst:+A+case+report+and+review+of+literature.">An uncommon finding of posterior cruciate ligament intrasubstance cyst: A case report and review of literature.</a> J Orthop Case Rep. 12 (3), 61-63 (2022).</li><li>Jawish, R., Nemer, C., Assoum, H., Haddad, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cyst+of+the+anterior+cruciate+ligament+in+children.">Ganglion cyst of the anterior cruciate ligament in children.</a> J Pediatr Orthop B. 18 (5), 234-237 (2009).</li><li>Bui-Mansfield, L. T., Youngberg, R. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intraarticular+ganglia+of+the+knee:+Prevalence,+presentation,+etiology,+and+management.">Intraarticular ganglia of the knee: Prevalence, presentation, etiology, and management.</a> Am J Roentgenol. 168 (1), 123-127 (1997).</li><li>Recht, M. P., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+MR+appearance+of+cruciate+ganglion+cysts:+A+report+of+16+cases.">The MR appearance of cruciate ganglion cysts: A report of 16 cases.</a> Skeletal Radiol. 23 (8), 597-600 (1994).</li><li>Dinakar, B., Khan, T., Kumar, A., Kumar, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cyst+of+the+anterior+cruciate+ligament:+A+case+report.">Ganglion cyst of the anterior cruciate ligament: A case report.</a> J Orthop Surg. 13 (2), 181-185 (2005).</li><li>Hameed, S. A., Sujir, P., Naik, M. A., Rao, S. K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ganglion+cyst+of+the+posterior+cruciate+ligament+in+a+child.">Ganglion cyst of the posterior cruciate ligament in a child.</a> Singapore Med J. 53 (4), e80-e82 (2012).</li><li>Tie, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+manifestation+and+arthroscopic+treatment+of+symptomatic+posterior+cruciate+ligament+cyst.">Clinical manifestation and arthroscopic treatment of symptomatic posterior cruciate ligament cyst.</a> J Orthop Surg Res. 13 (1), 84 (2018).</li><li>Lankes, M., Petersen, W., Hassenpflug, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Arterial+supply+of+the+femoral+condyles.">Arterial supply of the femoral condyles.</a> Z Orthop Ihre Grenzgeb. 138 (2), 174-180 (2000).</li><li>McCarthy, M. M., Hannafin, J. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+mature+athlete:+Aging+tendon+and+ligament.">The mature athlete: Aging tendon and ligament.</a> Sports Health. 6 (1), 41-48 (2014).</li><li>Petersen, W., Tillmann, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blood+and+lymph+supply+of+the+posterior+cruciate+ligament:+A+cadaver+study.">Blood and lymph supply of the posterior cruciate ligament: A cadaver study.</a> Knee Surg Sports Traumatol Arthrosc. 7 (1), 42-50 (1999).</li><li>Simank, H. G., Graf, J., Schneider, U., Fromm, B., Niethard, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Demonstration+of+the+blood+supply+of+human+cruciate+ligaments+using+the+plastination+method.">Demonstration of the blood supply of human cruciate ligaments using the plastination method.</a> Z Orthop Ihre Grenzgeb. 133 (01), 39-42 (1995).</li><li>Tang, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Surgical+techniques+in+the+management+of+pediatric+anterior+cruciate+ligament+tears:+Current+concepts.">Surgical techniques in the management of pediatric anterior cruciate ligament tears: Current concepts.</a> J Child Orthop. 17 (1), 12-21 (2023).</li></ol>

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.
<p class="...

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 border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Arthroscopic sheath&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200829</td>
			<td>6mm</td>
		</tr>
		<tr>
			<td>Arthroscopy</td>
			<td>smith&#38;nephew</td>
			<td>72202087</td>
			<td>30 mm x 4 mm</td>
		</tr>
		<tr>
			<td>Beam guide&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72204925</td>
			<td>5 mm x 3.6 m</td>
		</tr>
		<tr>
			<td>Beam guide-arthroscopy end connector&#160;</td>
			<td>smith&#38;nephew</td>
			<td>2143</td>
			<td></td>
		</tr>
		<tr>
			<td>Beam guide-panel connector&#160;&#160;</td>
			<td>smith&#38;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&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>4356</td>
			<td>4 mm</td>
		</tr>
		<tr>
			<td>Camera&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200561</td>
			<td>NTSC/PAL</td>
		</tr>
		<tr>
			<td>Coupler&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72200315</td>
			<td></td>
		</tr>
		<tr>
			<td>DYONICS POWER II</td>
			<td>smith&#38;nephew</td>
			<td>72200873</td>
			<td>100-24VAC, 50/60Hz</td>
		</tr>
		<tr>
			<td>DYONICS POWERMAX ELITE</td>
			<td>smith&#38;nephew</td>
			<td>72200616</td>
			<td></td>
		</tr>
		<tr>
			<td>Endoscopic camera system</td>
			<td>smith&#38;nephew</td>
			<td>72201919</td>
			<td>560P NTSC/PAL</td>
		</tr>
		<tr>
			<td>HD monitor&#160;</td>
			<td>smith&#38;nephew</td>
			<td>&#160;LB500031</td>
			<td>27 inch&#160;</td>
		</tr>
		<tr>
			<td>Hook probe&#160;</td>
			<td>smith&#38;nephew</td>
			<td>3312</td>
			<td></td>
		</tr>
		<tr>
			<td>Incisor plus platinum shaver&#160;&#160;&#160;&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>72202531</td>
			<td>&#160;4.5 mm</td>
		</tr>
		<tr>
			<td>Lumbar needle&#160; AN-E/S&#160;<img alt="Equation 1" src="/files/ftp_upload/65620/65620eq01.jpg" style="margin: auto;" /></td>
			<td>tuoren</td>
			<td>AN-E/S&#160;<img alt="Equation 1" src="/files/ftp_upload/65620/65620eq01.jpg" style="margin: auto;" /></td>
			<td>1.6 mm x 80 mm</td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,left&#160;&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207602</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,right&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207601</td>
			<td></td>
		</tr>
		<tr>
			<td>Micropunch,teardrop,straight&#160;</td>
			<td>smith&#38;nephew</td>
			<td>7207600</td>
			<td></td>
		</tr>
		<tr>
			<td>Pitbull Jr. Grasper&#160;&#160;</td>
			<td>smith&#38;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.

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

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

Cruciate ligament knee cysts, particularly posterior ones, are uncommon. Arthroscopic surgery is the preferred treatment, due to minimal trauma, low recurrence and quick recovery. Making it the most common choice for complete cyst removal.Posterior cruciate ligament cysts located behind the ligament are treated with a double posteromedial approach during arthroscopic surgery. This approach in first developed visual for complete cyst removal;simplifying the procedure with minimal trauma, less recovery and no recurrence. Our surgical approach is particularly suitable for the removal of cysts located on the dorsal side of the posterior cruciate ligament.The third approach is more advantageous if the set is compartmentalized or close to the tibial end.

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 patie...

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

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