Extensor Tendon Repair — Zone III Central Slip Short Arc Motion (SAM)

UW Health Orthopedic Surgery; UnityPoint Health - Meriter Rehabilitation · Dr. Michelotti; Dr. Gander; Dr. Salyapongse

Weight-Bearing

NWB surgical UE

Key Restrictions

No lifting/pushing/pulling >2 lbs involved UE; no WB involved UE; no forceful gripping; orthosis 24/7 except hygiene and SAM exercises

Timeline & Phases

Phase I (2–5 days to 2 wks): volar gutter PIP full extension + volar exercise splint (wrist 30° flex; CS only: PIP/DIP 20° flex block; CS+LB: PIP flex block, DIP in extension); 20 reps/hour SAM flexion to template then extension to neutral using minimal active tension; edema/wound/scar management | Phase II (2–4 wks): progress exercise template 10° flexion weekly; if extension lag develops, hold exercises 1 wk then reassess; orthosis 24/7 except hygiene/exercises | Phase III (4–5 wks): wean daytime orthosis for sedentary/light ADLs; gentle AROM MP/PIP/DIP; night extension splint; if >10° lag, consider spring extension splint; at 5 wks if no lag initiate composite flexion | Phase IV (6–8 wks): night extension splint through 8 wks then D/C if no lag; PROM at 8 wks if persistent stiffness/weakness and no lag; strengthening at 10 wks

Notes

Short Arc Motion (SAM) protocol; surgeons: Dr. Michelotti, Dr. Gander, Dr. Salyapongse; two variants: CS only (DIP free in exercise splint) and CS+LB (DIP in extension in exercise splint); extension lag = hold exercises; progress when no lag; tissue maturation may take up to 1 year in resistant cases; shared URL with Conservative protocol; developed collaboratively by UW Health and UnityPoint Health - Meriter Rehabilitation

Surgeon / Author

Dr. Michelotti; Dr. Gander; Dr. Salyapongse