Back to 2025 Abstracts
Tip-Tip Pinch Strength Following Median Nerve Decompression: Comparing Lacertus, Carpal Tunnel, and Double Crush Release.
Ileen Domela Nieuwenhuis, MD
1,
2; Sjoerd B Paulusma, MD
2; Niels WL Schep, MD PhD
3; J. Henk Coert, MD PhD
1; Jean Bart Jaquet, MD PhD
4
1University Medical Center Utrecht, Utrecht, Utrecht, Netherlands; 2Maasstad Hospital, Rotterdam, Zuid-Holland, Netherlands; 3Maasstad Ziekenhuis, Rotterdam, Netherlands; 4Maasstad Hospital, Rotterdam, Netherlands
Introduction: Tip-tip pinch weakness may help differentiate proximal and distal median nerve compression, such as carpal tunnel syndrome (CTS). Tip-tip pinch involves FPL and FDP2 flexion, both innervated by the anterior interosseous nerve (AIN), a median nerve branch in the forearm. These muscles remain unaffected in CTS. Proximal median nerve decompression positively affects the AIN and its motor signals, potentially restoring strength immediately. This study examines tip-tip pinch strength after Lacertus release (LR), carpal tunnel release (CTR), and combined LR and CTR to compare the effects of proximal and distal median nerve decompressions.
Methods: We included LR (n=20), combined LR and CTR (n=20), and CTR (n=20) patients. Diagnoses were based on clinical examination and neurophysiological testing. Tip-tip pinch strength was measured using a Baseline Pinch Gauge, immediately preoperatively, 5-10 minutes and three months postoperatively. Measurements were repeated thrice, and means were compared to normative ranges (meanąSD) based on sex, age, and hand dominance. Changes in strength were assessed relative to baseline.
Results: 60 patients were included (Table 1). The median strength gain for LR patients was +57% (IQR +30, +90) immediately postoperative, and +55% (IQR +30, +85) after three months. Combined LR and CTR patients improved by +32% (IQR -15, +60), and +41% (IQR +6, +55), respectively. CTR patients changed by -10% (IQR -25, -1), and +5% (IQR 0, +24), respectively (Fig 1). A decrease in strength may be attributed to patients' fear of complications. Preoperatively, three LR patients (15%) met their normative strength range, improving to 15 (79%) after three months, compared to 10 CTR patients (50%) preoperatively and 11 (65%) after three months (Fig 2).
Conclusions: Tip-tip pinch strength improves immediately and sustains following Lacertus release, both solitary and combined with CTR. Solitary CTR did not change strength, highlighting the importance of proximal decompression in restoring tip-tip pinch strength. Return of tip-tip pinch strength after proximal median nerve decompression is evident and may be a valuable diagnostic tool to differentiate from CTS.
Back to 2025 Abstracts
