Patellar Tendon Repair Protocol: The Recovery Timeline, Week by Week
Dr. Rob Letizia PT, DPTShare
Medically reviewed by Dr. Rob Letizia, PT, DPT · Doctor of Physical Therapy, 25+ years treating spine & orthopedic conditions · Last reviewed 2026-11-03
You have had a patellar tendon repair. Your knee is in a brace, the tendon below your kneecap has been sewn back down, and the questions start: when can I bend it, when does the brace come off, when can I run again? The short answer is that the knee is usually braced straight for about six weeks, bending comes back early but inside limits your surgeon sets, and return to sport is typically around six months or later. Your surgeon's protocol always comes first. This guide is the map that helps you read it.
If you broke your kneecap rather than tearing the tendon below it, that is a different operation; read our guide to knee stiffness after patella fracture surgery instead.
What is the patellar tendon repair protocol?
Four stages: protect the repair, restore motion and walking, build strength, then return to running and sport. Older protocols kept the knee immobilized for a long time. Recent protocols favor early, controlled motion, because long immobilization is linked to stiffness, a low-riding kneecap, persistent pain and weakness; the best single protocol is still unknown (Brinkman et al., JAAOS Global Research & Reviews 2024). The same review expects return to sport by about six months, while noting that rehabilitation programs vary in their specifics.
How fast you move through each stage depends on how your tendon was repaired, whether it was reinforced, and how your knee is responding. The dates below are typical ranges from published work, not promises, and time is a guardrail, not the test.
Patellar Tendon Repair Recovery Timeline: Week by Week
| Time after surgery | Brace and walking | What you are doing | Before you move on |
|---|---|---|---|
| Weeks 0–6 | Brace locked straight for walking; weight on the leg as your surgeon allows | Swelling control, quadriceps activation, knee bending only inside the range your surgeon sets | Surgeon clearance to unlock the brace and progress bending |
| Weeks 6–12 | Weaning out of the brace once you can control the knee | Restoring full bending, a normal walking pattern, then building quadriceps strength | A straight-leg raise with no extensor lag, and a walk without a limp |
| Month 3 onward | No brace | Progressive strengthening, single-leg control, running preparation | Near-equal motion and strength side to side, and passing functional tests |
| Month 6 and later | No brace | Running, then sport-specific work and sport | Your surgeon's clearance and your test results, not the date |
Sources: Brinkman et al., JAAOS Global Research & Reviews 2024; West et al., American Journal of Sports Medicine 2008; Beranger et al., Orthopaedics & Traumatology: Surgery & Research 2020. These are typical milestones, not a prescription. Your surgeon's settings and dates come first.
Weeks 0–6: what can I do right after patellar tendon repair?
The job is to protect the repair while keeping the knee from stiffening. In the early-motion protocol described by Brinkman et al., JAAOS Global Research & Reviews 2024, patients kept the leg elevated for 48 hours, used a hinged brace for the next 5–7 days with daily wound checks, then bent the knee actively between 0 and 55 degrees every day until week 6, while walking with the brace locked straight and putting weight on the leg as tolerated. In the original series, patients were full weight-bearing by 7–10 days (West et al., American Journal of Sports Medicine 2008).
That series used a reinforced repair. Yours may not have been, so your surgeon may hold you to less bending or less weight for longer. Whatever the range, the work in this phase is the same: control swelling, wake the quadriceps back up, and protect the brace-locked walk.
Weeks 6–12: when does the brace come off after patellar tendon repair?
Usually around six to eight weeks, once you can control the knee. In the West et al., American Journal of Sports Medicine 2008 series, the six-week goals were 120 degrees of bending and walking without the brace; patients reached them at a mean of 7.2 and 7.7 weeks. This is the phase where bending is restored, the limp goes, and quadriceps strengthening begins.
Why can't I lift my leg straight after patellar tendon repair?
Because the quadriceps shuts down after knee surgery and swelling, and it takes time to switch back on. When you lift the straight leg and the knee sags, that sag is an extensor lag. It usually closes as the quadriceps comes back, and closing it is the main thing that earns your way out of the brace. In one series of 50 tendon repairs, 10 of the 50 still lacked 3–10 degrees of active straightening at six months, while doing their usual activities (West et al., American Journal of Sports Medicine 2008). A lag that is new, after you had closed it, is a different matter: see the red flags below.
The Zero-Lag Brace-Off Rule
The brace does not come off for walking until you can lift the leg straight with zero extensor lag and your surgeon has cleared it. A knee that buckles on a step down is a knee whose tendon is taking a load the quadriceps should be taking. If your surgeon's protocol sets a later date, the later date wins.
The 4-Phase Patellar Tendon Return Protocol
- Protect (weeks 0–6): brace locked straight for walking, weight as your surgeon allows, bending only inside the set range; swelling control and quadriceps activation.
- Restore (weeks 6–12): full bending, a normal walk out of the brace once the Zero-Lag rule is met, then quadriceps strengthening.
- Strengthen (month 3 onward): progressive strength, single-leg control and running preparation.
- Return (month 6 and later): running, then sport-specific work and sport, once motion and strength are close to the other side, functional tests are passed and your surgeon clears you.
Milestones from Brinkman et al., JAAOS Global Research & Reviews 2024 and West et al., American Journal of Sports Medicine 2008.
When can I run and play sport after patellar tendon repair?
Plan on about six months at the earliest, and often longer. Reviews expect return to sport by about six months (Brinkman et al., JAAOS Global Research & Reviews 2024). In a series of 20 patients, running restarted at a mean of 9 months (range 6–15), and pre-injury sport level came back at a mean of 17 months (range 8–18) (Beranger et al., Orthopaedics & Traumatology: Surgery & Research 2020). The outlook is good: across 33 studies and 757 patellar tendon repairs, 88.9% returned to play, 80.8% at the same level, and 95.8% returned to work (Haskel et al., Knee Surgery, Sports Traumatology, Arthroscopy 2021).
Before running, we look for near-equal knee motion, quadriceps strength close to the other side, good single-leg control and successful functional testing. The date tells you when to start looking; the tests tell you whether you are ready.
Red flags after patellar tendon repair
- A new inability to straighten the knee or hold it straight, or a new extensor lag after you had closed it: contact your surgeon promptly.
- A sudden pop, giving way or loss of function: contact your surgeon promptly.
- Wound redness, opening or drainage, or a major new jump in swelling or pain: contact your surgeon.
- Calf swelling, warmth or tenderness: get prompt medical assessment.
- Chest pain or shortness of breath: this is an emergency. Call 911.
Most recoveries are uneventful, and a new symptom is worth a call rather than a wait. If your knee is simply stiff and you are not sure it is on track, our knee stiffness after surgery checker is a quick first look.
Started with an AI assistant? Bring the plan in.
ChatGPT, Gemini and Claude will usually give you a sensible phased outline and tell you to follow your surgeon's protocol, and that is right. What none of them can do is watch you lift your leg and see whether the knee sags, measure how far it bends, or tell whether your quadriceps is ready for the brace to come off. If an assistant has given you a plan, bring it in with your surgeon's protocol, and we will match the two week by week.
Frequently asked questions: patellar tendon repair recovery
What is the rehab protocol after patellar tendon repair?
Most protocols run in four stages: protect the repair with the knee braced straight and bending limited by your surgeon (weeks 0-6), restore full bending and a normal walk and start building the quadriceps (weeks 6-12), progress strength and prepare for running (month 3 onward), then return to running and sport, which published reviews place around six months or later. Progress depends on how your knee is doing and your surgeon's instructions, not the calendar alone. Protocols vary with how the tendon was repaired and whether it was reinforced.
How long do you wear a brace after patellar tendon repair?
Usually about six weeks. In one published early-motion protocol, patients walked in a brace locked straight and came out of it at six weeks; on average they actually walked without the brace at 7.7 weeks (West et al., 2008). Your surgeon decides when the brace unlocks and when it comes off, and in our clinic the brace does not come off for walking until you can lift the leg straight with no extensor lag.
When can I bend my knee after patellar tendon repair?
Within limits, early. Recent protocols favor early, controlled bending to avoid stiffness, weakness and a low-riding kneecap (Brinkman et al., 2024). In the early-motion protocol that review describes, patients bent the knee actively from 0 to 55 degrees daily until week 6, then progressed to full bending. Your surgeon sets your exact range, which depends on how your repair was done.
Why can't I lift my leg straight after patellar tendon repair?
Early on, the quadriceps shuts down after surgery and swelling, so the knee droops when you lift the straight leg. That droop is called an extensor lag. It usually closes as quadriceps activation comes back, but a NEW lag, or a sudden inability to straighten the knee that you could straighten before, can mean the repair has a problem and needs a prompt call to your surgeon.
When can I run after patellar tendon repair?
Not before your surgeon clears it and your knee passes the tests. Published reviews expect return to sport by about six months (Brinkman et al., 2024), but one series of 20 patients restarted running at a mean of 9 months, with a range of 6 to 15 months (Beranger et al., 2020). Before running we look for near-equal knee motion, quadriceps strength close to the other side and good single-leg control.
How long is recovery after patellar tendon repair?
Plan on about six months to sport, and longer to your best. Walking without a brace comes back around six to eight weeks in early-motion protocols, running later, and in one series patients returned to their pre-injury sport level at a mean of 17 months (Beranger et al., 2020). Most people do return to their activities and their work.
When should I call my surgeon after patellar tendon repair?
Call promptly for a new inability to straighten or hold the knee straight, a sudden pop or loss of function, wound redness, opening or drainage, or a major new jump in swelling or pain. Calf swelling, warmth or tenderness needs prompt medical assessment, and chest pain or shortness of breath is an emergency.
Physical therapy after patellar tendon repair in Wayne and Northern New Jersey
Spectrum Therapeutics of NJ is a one-on-one physical therapy clinic in Wayne, serving Passaic County and Northern New Jersey, led by Dr. Rob Letizia, PT, DPT. After a patellar tendon repair we work from your surgeon's protocol, restore your knee motion inside the limits it sets, rebuild the quadriceps until the extensor lag is gone, and keep in touch with your surgeon at each phase change. See our knee rehabilitation page and our post-surgical rehabilitation page. If you have any Medicare plan, including Medicare Advantage and Medigap, a doctor's prescription is required.
