Comfort is a position before it is a technique
Most grooming routines assume a dog who can stand square on a table for half an hour, be lifted, and hold a leg up on request. An arthritic dog can do none of that comfortably, and the standing itself — weight shifting onto sore hips, elbows and shoulders on a hard or slippery surface — is often the worst part of the session, not the brush. Rebuild the routine around lying down: a thick memory-foam mat or folded blankets on the floor, in a warm room, with you sitting beside him rather than him raised to your height. Groom the upper side thoroughly, then let him get up, move around, and settle on his other side in his own time rather than rolling him over.
Legs, paws and nails at resting angles
Joint handling is where grooming most often hurts an arthritic dog. Never lift a leg higher than he lifts it himself, and never hold a paw bent or extended while you work on it — support the leg from underneath in the angle it naturally rests at, and bring the brush or clippers to the paw instead of the paw to the tool. For nails, raise the foot just clear of the mat, trim, and set it down between nails if he needs the breaks. If a rear leg is too stiff to lift safely at all, trim what you can reach with the foot flat, a sliver at a time, or ask your groomer or vet to handle that foot during visits when he is already being helped into position.
Short sessions, split across days
An arthritic dog stiffens as a session goes on, and a dog who associates grooming with the ache afterwards will resist from the start next time. Aim for sessions measured in minutes: brush and check the coat on one day, paws and nails on another, ears and a wipe-down on a third. Stop while he is still relaxed, and let him end with something pleasant — a gentle massage over the muscles around, never directly on, the sore joints, if he enjoys touch there. Choose his best time of day for anything demanding; many arthritic dogs are stiffest first thing in the morning and loosest after a gentle midday walk and a warm rest, so schedule around the dog you actually have, not the clock.
Coat work that avoids pulling on sore places
Tangles over hips, elbows and shoulders are a particular problem, because brushing them out transmits every tug straight into the joint beneath. Soften knots with conditioner and your fingers first, hold the base of the hair against the skin so the skin does not take the pull, and clip out any mat that resists rather than combing through it — a small bald patch is a fair trade for a pain-free dog. Keep the coat itself in an easier trim if his breed allows it; a shorter, low-maintenance cut means shorter sessions and less daily brushing for the rest of his life, which matters more than a show outline on a dog whose priority is comfort. Watch his face and body throughout: lip-licking, turning toward your hand, panting or trying to rise are requests to pause, and honouring them keeps him cooperative.
Sharing the split routine with his other carers
Arthritis grooming works best as a written plan, because the comfort rules — lying down, no high leg lifts, short sessions, his good time of day — are easy for a well-meaning helper to break in a single enthusiastic session. Note his sore joints and his preferred positions alongside the plan. KinsLe Care Teams lets you break your dog's grooming into those small separate duties across the week and assign them to whoever is home, each marked complete with a timestamp, so his coat, nails and ears all get done without any one session asking more of his joints than they can give.