Selective neurectomy as surgical treatment for infrapatellar pain syndrome: A systematic review and meta-analysis

Injury to the cutaneous nerves around the knee can result in neuropathic pain and functional impairment, commonly referred to as infrapatellar pain syndrome (IPS). This meta-analysis evaluates clinical outcomes of selective neurectomy for the treatment of IPS.

MEDLINE, Embase, CENTRAL, and Web of Science were systematically searched for studies reporting clinical outcomes following selective neurectomy for IPS. A single-arm meta-analysis was performed using random-effects models. Pooled estimates are presented as mean differences (MDs) for continuous outcomes and event rates for dichotomous variables, each with corresponding 95% confidence intervals (CIs).

After screening 1018 studies, eight retrospective observational case series comprising 261 patients were included. The weighted mean age was 56.0 years (SD 12.9). Women were more commonly affected than men (69.9% vs. 30.1%). Primary and revision total knee arthroplasty were the most frequent precursors to IPS (54.0% of cases). The infrapatellar branch of the saphenous nerve was most affected (96.6% of patients), followed by the medial (44.4%) and lateral (25.7%) retinacular nerves. Weighted mean follow-up was 2.9 years (SD 1.3). All patients underwent local anaesthetic blockade prior to surgery. Pooled analysis of pre- versus postoperative Visual Analog Scale (VAS) scores demonstrated a significant reduction in pain (MD -5.6, [95% CI: -7.4 to -3.9]). The Knee Society Score showed significant postoperative improvement (MD 36.3 [95% CI: 23.4-49.2]). The pooled event rates for complications and revision surgery were low (1% [95% CI: 0-5%] and 2% [95% CI: 0-5%], respectively). Meta-regression analysis showed no statistically significant correlation between preoperative neuropathic pain duration and VAS improvement.

Selective neurectomy for IPS is associated with substantial pain relief, improved functional outcomes, and low rates of complications and revision surgery. While the available evidence is limited to retrospective observational studies, these findings support its role as an effective treatment in appropriately selected patients. A positive response to diagnostic local anaesthetic blockade appears to be a strong predictor of favourable surgical outcome and should be considered essential in patient selection.