Anterior cruciate ligament ganglion causing flexion restriction: a case report and review of literature

Role of ultrasound-guided decompression in management of mucoid degeneration of the anterior cruciate ligament

OBJECTIVE

To assess the effectiveness of ultrasound-guided decompression in managing symptomatic mucoid degeneration of the anterior cruciate ligament (ACL).

MATERIALS AND METHODS

Retrospective analysis of 55 patients who underwent ultrasound-guided ACL mucoid degeneration decompression between July 2013 and August 2019. Subjective satisfaction scores were gathered immediately post-procedure for all 55 patients; follow-up satisfaction scores (scale of 0-10, 10 being excellent) were gathered telephonically for 46 patients (83.6%) up to 63 months post-procedure. Follow-up duration of each patient was classified as short (1-6 months), intermediate (7-12 months), or long (more than 12 months) post-procedure. Forty-five patients (81.8%) MRI were retrospectively analyzed and classified into cystic (n = 13, 28.9%), mucoid (n = 11, 24.4%), or mucoid-cystic (21, 46.7%) types. Multivariate logistic regression was used to identify associations between follow-up satisfaction score, follow-up duration, patient age, and type of ACL degeneration.

RESULTS

All patients had immediate marked post-procedure improvement, with excellent (>7/10) satisfaction scores. Forty-six of 55 patients were telephonically followed up: 21 (45.6%) short-term interval, 18 (39.1%) intermediate term, and 7 (15.2%) long-term. Thirty (65.22%) patients had excellent and eight (17.4%) patients had average satisfaction scores at follow-up. Eight (17.4%) patients had poor post-procedure satisfaction scores within six months. There were no significant associations between immediate or follow-up satisfaction score and duration of follow-up, age of patient, or type of ACL degeneration.

CONCLUSION

Ultrasound-guided aspiration, fenestration, and injection are an effective, safe, minimally invasive and radiation-free technique for management of mucoid degeneration of ACL with excellent immediate- and long-term results.

Inverted deltoid posterior cruciate ligament femoral insertion accompanied with medial synovial fold: a case of a complex posterior cruciate ligament anatomical variation recalcitrant to conservative treatment

PURPOSE

The present study aims to report a symptomatic rare anatomical variation of the posterior cruciate ligament (PCL) that was encountered during arthroscopy.

CASE PRESENTATION

A 34-year-old female suffered from dull anterior pain in the right knee, along with stiffness and the presence of an audible click and occasionally locking during deep knee flexion. Physical examination revealed only slight pain during single-leg squatting and mild knee effusion with painful limitation of the last degrees of flexion. Following unsuccessful conservative treatment, knee arthroscopy was performed in which the PCL was found to be hypertrophic, having a broad femoral insertion that almost completely occupied the intercondylar notch and impinged the anterior cruciate ligament. Moreover, the PCL presented a large medial synovial fold that formed a plica inserting to the medial meniscus's posterior horn. Ligamentoplasty was performed by excising one-third of the PCL lateral portion. The PCL medial synovial fold and the plica attaching to the medial meniscus were resected. The patient was allowed to return to full activity when her symptoms resolved, and the knee function was restored, at 5 weeks post-operatively.

CONCLUSION

The current study presented a rare and complex anatomical variation of the PCL that was symptomatic and recalcitrant to conservative treatment. Magnetic resonance imaging (MRI) can reveal the variant morphology of the PCL, and arthroscopy provides the definite treatment. This case report may be useful for orthopaedic surgeons and radiologists to consider anatomical PCL variations during differential diagnosis in patients with non-specific clinical presentation and findings.

Clinical Outcomes of Arthroscopic Notchplasty and Partial Resection for Mucoid Degeneration of the Anterior Cruciate Ligament

Background: Mucoid degeneration of the anterior cruciate ligament (MD-ACL) is a chronic degenerative process involving a hypertrophied ACL, which may lead to notch impingement syndrome. As a treatment method, there is consensus regarding arthroscopic resection for MD-ACL resulting in good clinical outcomes; however, additional notchplasty remains controversial. The purpose of this study was to investigate clinical outcomes after arthroscopic partial resection of the ACL and additional notchplasty performed to minimize volume reduction of the ACL. Study Design: Level IIIb retrospective cohort study. Methods: Of 1810 individuals who underwent knee arthroscopic surgery performed by the same surgeon between July 2011 and October 2020, 52 were included, while 10 were excluded due to a follow-up period of <1 year. Clinical data including pain location, terminal flexion or extension pain, range of motion (ROM), Lysholm knee score, and Hospital for Special Surgery (HSS) knee score were assessed pre- and postoperatively. Additionally, according to the resected volume of the ACL, patients were classified into two groups: <25% (Group 1), and 25–50% (Group 2). Clinical outcomes were compared between the two groups. Results: There were 17 (40.5%) men and 25 (59.5%) women with a mean age of 53.9 years (range, 16–81 years) at the time of surgery. The mean duration of symptoms before surgery was 14.4 months (range, 3–66 months). Arthroscopic partial resection of the MD-ACL was performed in all patients, and concomitant notchplasty was performed in 36 (81.8%). All clinical scores improved postoperatively, and were statistically significant (p < 0.01). However, there was no significant difference in clinical outcomes between groups 1 and 2 classified according to the resected ACL volume. Recurrence of MD-ACL was recorded in only one patient, 11 months after arthroscopic treatment. No patients underwent ACL reconstruction because of symptoms of anterior instability. Conclusion: Arthroscopic partial resection of the ACL and concomitant notchplasty yielded satisfactory outcomes for the treatment of MD-ACL. Notchplasty may be an alternative procedure to avoid total ACL resection and postoperative instability.

Symptomatic Posterior Cruciate Ligament Ganglion Cyst in a Child with Hemophilia: A Case Report

CASE

We report the case of an active 8-year-old boy with a history of hemophilia and with a 1-year history of knee pain and limited range of motion. Magnetic resonance imaging of the knee demonstrated a ganglion cyst arising from the posterior cruciate ligament (PCL). Arthroscopic decompression of the cyst was performed, and he was asymptomatic at the 1-year follow-up.

CONCLUSION

This case demonstrates a rare finding of a pediatric PCL ganglion cyst. We suggest that clinicians should be aware of this as a cause of knee pain in the pediatric population and that arthroscopic management can be successful.

Anterior Cruciate Ligament Ganglion Cyst and Mucoid Degeneration: A Review

Mucoid degeneration and ganglion cyst are two distinct non-traumatic lesions of the anterior cruciate ligament (ACL) that most commonly occur discretely but occasionally coexist. They are relatively uncommon, and their exact aetiopathogenesis is still not clear. ACL ganglion cyst occurs more frequently among relatively younger patients compared to mucoid degeneration. They could be asymptomatic and discovered incidentally while evaluating the knee for other pathologies. Symptomatic cases of the two conditions present with nonspecific chronic pain, painful limitation of terminal flexion and extension, and mechanical block (among other symptoms), similar to that of other internal derangement pathologies of the knee. Magnetic resonance imaging is the investigation of choice, and diagnostic criteria are defined. Arthroscopic management of these conditions efficiently provides an improvement in symptoms without instability. Computed tomography scan guided aspiration is also useful in selected cases of ACL ganglion cyst. ACL ganglion cyst and mucoid degeneration should be considered in the differential diagnosis of chronic knee pain and stiffness of unspecified etiology.