Impingement of infrapatellar fat pad (Hoffa's disease): results of high-portal arthroscopic resection.

PURPOSE: We performed a retrospective cohort study with prospective data collection to assess clinical and functional outcomes of painful impingement of the infrapatellar fat pad (Hoffa's disease) treated with high-portal arthroscopic resection.
METHODS: Hoffa's disease as an isolated lesion was confirmed by arthroscopy in 34 patients with recalcitrant anterior knee pain. The visualization portals were made high in the soft spot above the level of the lower pole of the patella. Patients were treated by resection of the affected part of the fat pad and assessed via the Lysholm knee and Tegner activity level scales preoperatively and at 3 months and at 1 year postoperatively, as well as at the conclusion of this study.
RESULTS: The mean age of the patients was 38 years (range, 19 to 62 years). The mean duration of symptoms before surgery was 10 months (range, 1 to 22 months). Twelve patients had one or more previous failed arthroscopies at other centers. The mean follow-up period was 68 months (range, 49 to 95 months). The mean improvement in Lysholm score was 44.76, 55.58, and 53.97 at 3 months, at 1 year, and at the latest follow-up, respectively. On the basis of the Tegner activity level, all but 4 patients returned to their preinjury status. A statistically significant negative correlation was found between duration of symptoms and gain in Lysholm score after surgery (Pearson r = -0.58). Three types of lesion were identified. After resection, patients with acute lesions (type 1) had a quicker return to their previous level of activity according to the Tegner scale as compared with patients with chronic lesions (types 2 and 3) (P = .05 and .03, respectively).
CONCLUSIONS: Patients with Hoffa's disease without any other concomitant pathology can expect resolution or long-term improvement in their symptoms and function after arthroscopic resection. LEVEL OF EVIDENCE: Level IV, therapeutic case series.