One to three years, in three stages.
How to tell which one you are in

The three stages, with timings

The capsule around the shoulder joint becomes inflamed, then thickens and tightens, then slowly loosens. Each stage has its own feel.

• Freezing, 2 to 9 months. Pain leads. It aches at rest, bites on sudden movements and wakes you when you roll on to that side. Range shrinks month by month.
• Frozen, 4 to 12 months. Pain eases to an ache at the end of each movement. Stiffness is at its worst. Reaching a back pocket, a bra strap or the top shelf is blocked.
• Thawing, 5 to 24 months. Range comes back in small steps, often noticed first when washing your hair or putting on a coat.

The stages overlap and the ranges are wide. Published averages sit at around 30 months from start to finish.

Which stage are you in?

Three questions place most people.

• Does it wake you most nights? Yes points to freezing.
• Is the pain mainly at the end of a movement, with a solid block? That is frozen.
• Can you reach further than you could two months ago? That is thawing.

One check is worth doing today. Stand with your elbow tucked into your side and bent to 90 degrees, then turn your forearm outward like opening a door. Compare sides. A frozen shoulder is blocked well short of the other arm, and it stays blocked when someone else moves it for you. If someone else can turn it nearly all the way, the problem is more likely the rotator cuff, which is a different plan.

What shortens each stage

The total length is hard to change. What you can change is how bad each stage is and how much range you keep.

• Freezing. A steroid injection into the joint has the best evidence for pain, with clear relief at six weeks. Ask your GP early. Keep exercise gentle and inside the pain-free range: pendulum swings and table slides, twice a day. Forceful stretching in this stage makes it worse.
• Frozen. Now the stretching goes up. Long holds of 30 to 60 seconds at the end of range, several times a day, with hands-on joint mobilisation. Tightness is the target. Sharp pain is the limit.
• Thawing. Strength through the new range: rows, wall slides, then light overhead pressing. Keep the range work going for three months after daily tasks feel easy.

For the physiotherapy side of each stage, including the questions people ask about injections, Mid Sussex Osteopaths in Haywards Heath has a guide to the three stages of frozen shoulder and how physiotherapy helps.

What happens in the long run

Most people get back to normal or near-normal use. In a long-term follow-up of 223 people at an average of four years, 59 per cent had normal or near-normal shoulders and 41 per cent had some remaining symptoms, mostly mild.

Two more facts help with planning. The same shoulder rarely freezes twice. The other shoulder is affected in up to one person in five within a few years, so early stiffness on the second side is worth acting on quickly.

Diabetes raises the risk and tends to lengthen the course. If you have had no blood sugar check in the last year, ask your GP for one.

What to do this month

Four steps, with dates.

• Week 1: do the elbow-at-side test and write down which stage fits.
• Week 1, freezing stage: book the GP and ask about an injection. Sort your sleep: lie on the other side with a pillow hugged to your chest.
• Weeks 1 to 4: do the exercise for your stage twice a day. At a desk, rest the forearm on the table so the shoulder hangs relaxed.
• Week 4: re-test. Note how far your thumb reaches up your back and compare with week one.

Straight answers