Baker's cysts (popliteal cysts) are fluid-filled swellings in the posteromedial knee region that commonly associate with intra-articular knee pathology. In the setting of knee arthroplasty, preexisting small cysts can enlarge postoperatively and cause symptomatic posterior swelling and restricted knee flexion. This case report describes a patient who developed a symptomatic enlarging Baker's cyst after total knee arthroplasty (TKA) and who was treated with a minimally invasive posteromedial arthroscopic decompression.
A 55-year-old man underwent TKA for advanced knee osteoarthritis. Preoperatively a small Baker's cyst was present. After the arthroplasty the cyst enlarged, producing progressive posterior knee swelling and limiting knee flexion. The abstract does not provide further details on radiographic or magnetic resonance imaging findings, implant specifics, or exact timing of symptom onset relative to the index arthroplasty beyond the statement that the cyst enlarged postoperatively.
Initial management included conservative measures: the cyst was aspirated and treated with a corticosteroid injection. These interventions failed to relieve the patient's symptoms or to prevent further growth of the cyst. No other nonsurgical measures or durations of conservative care are reported in the abstract.
Because conservative therapy was ineffective and the cyst caused progressive symptoms and restricted range of motion, the treating surgeons performed a posteromedial arthroscopic decompression of the Baker's cyst. The abstract identifies the procedure as posteromedial arthroscopy targeting the popliteal cyst but does not provide operative-step details, anesthesia type, perioperative complications, or intraoperative findings in the provided summary.
At 14 months after the arthroscopic decompression the patient was reported to be pain-free, to have full range of motion of the knee, and to have no clinical evidence of recurrence of the Baker's cyst. The abstract does not supply additional objective outcome measures, imaging confirmation of cyst resolution, patient-reported outcome scores, or longer-term follow-up beyond 14 months.
This case supports the use of posteromedial arthroscopy as a minimally invasive option to manage persistent, symptomatic Baker's cysts that do not respond to aspiration and corticosteroid injection after TKA. Arthroscopic techniques for treating popliteal cysts have been described in the literature for adults with associated intra-articular pathology; this report extends that concept to the postoperative TKA population.
The authors list keywords emphasizing the relevant clinical themes: Baker's cyst, knee arthroscopy, popliteal cyst, posteromedial arthroscopy, and total knee arthroplasty. The article is categorized as a Case Report in JBJS Case Connect, and disclosure information is available with the full online article per the journal's statements. The abstract references prior literature concerning prevalence, associated intra-articular lesions, and arthroscopic treatment outcomes for popliteal cysts, but specific comparative data or series-level outcomes are not included in the abstract.
For this single patient, posteromedial arthroscopic decompression led to resolution of symptoms and no clinical recurrence at 14 months after surgery. The authors conclude that posteromedial arthroscopy is an effective, minimally invasive option for persistent symptomatic Baker's cysts following total knee arthroplasty. The abstract does not report detailed operative technique, imaging data, or broader case series data; readers interested in those specifics should consult the full text and the referenced literature.
This summary is based on the abstract of the published case report (PMID: 42721365; DOI: 10.2106/JBJS.CC.26.00217). The abstract cites prior reviews and arthroscopic series on popliteal cysts; the full article includes a Conflict of Interest statement and the Disclosure of Potential Conflicts of Interest forms as noted by the journal. The abstract provides limited procedural and diagnostic details; those were not reported in the abstract provided here.