An ACL tear can stop an athlete mid-stride and leave a weekend warrior wondering if they'll ever pivot again. We diagnose quickly, walk you through every option, and build a recovery plan around the life — and the sport — you want to get back to.
MRI through our imaging partners and return-to-play protocols built around your sport.
The anterior cruciate ligament — the ACL — is one of four ligaments that hold your knee together. It runs diagonally through the middle of the joint, connecting the femur to the tibia, and its job is to keep the knee from sliding forward and rotating out of place when you pivot, plant, or land from a jump.
Most ACL tears happen in a split second. A soccer player plants a foot and twists. A skier catches an edge. A basketball player lands awkwardly from a rebound. There's often a popping sound or sensation, followed by swelling within a few hours and a knee that suddenly feels unreliable — like it can't be trusted on stairs, slopes, or quick changes of direction.
The injury falls on a spectrum. Partial tears leave some of the ligament intact and may stabilize with rehab. Complete tears — the more common scenario — don't heal on their own, because the ACL lives in a fluid-filled joint that prevents the kind of clotting that heals other ligaments. Whether a complete tear needs surgery is a separate question, and it depends entirely on what you want to do with the knee.
At LAOSS, our sports-medicine surgeons treat ACL injuries every week. We don't push surgery on patients who don't need it, and we don't undertreat athletes who do. The conversation starts with an exam, an MRI when warranted, and an honest look at your goals.
This injury is a tearing of the ACL ligament in the knee joint. The ACL ligament is one of the bands of tissue that connects the femur to the tibia. An ACL tear can be painful. It can cause the knee to become unstable.
Animations licensed from ViewMedica · Swarm Interactive
The anterior cruciate ligament is a short, dense band of tissue — about the size of your little finger — that crosses the inside of the knee. Together with the PCL it forms an X shape that controls how the femur and tibia move on one another. When it tears, the bones can shift in ways the body wasn't built for, which is what creates the giving-way feeling so many ACL patients describe.
Most ACL tears are diagnosed in clinic, not on a scan. The story is often unmistakable — a pivot, a pop, a swollen knee — and a careful exam confirms it. We use specific maneuvers like the Lachman test, anterior drawer, and pivot shift to feel directly for the laxity that a torn ACL produces. In experienced hands, these tests are remarkably accurate.
We then confirm with imaging. Weight-bearing X-rays rule out fracture and tell us about the bones. MRI shows the ligament itself, plus the menisci, cartilage, and bone bruise pattern that often comes with an ACL injury. About half of ACL tears come with a meniscus injury, and many show bone bruising on the femur and tibia where the bones collided as the ligament gave way — both of which change the treatment plan.
Your first visit at LAOSS is built to give you answers, not a maze of referrals. Most ACL patients leave with a confirmed working diagnosis, an MRI scheduled within the week, and a clear next step — whether that's a surgical consult or a structured rehab plan with your in-network physical therapist.
Not every ACL tear needs surgery. The right path depends on the tear pattern, your activity goals, the condition of the rest of the knee, and how unstable it feels day-to-day. We lay out every option, the trade-offs of each, and the realistic timeline before you decide.
For partial tears, less active patients, and people who can structure their lives around a stable knee, non-surgical care can work — and works best when started early and followed consistently.
For active patients, athletes, and anyone whose knee continues to give out, reconstruction restores the ligament with a graft and gets you back to the activities you care about.
ACL reconstruction is one of the most technique-sensitive operations in orthopedics. Tunnel placement, graft tensioning, and addressing companion injuries all sit within millimeters of right and wrong.
Our sports-medicine team moves stepwise — diagnose accurately, treat conservatively when it fits, and reconstruct with the precision the knee deserves when surgery is the right call.
If most of these match your situation, an evaluation with a sports-medicine knee specialist is the next step.
These signs typically point toward an in-person evaluation with a knee specialist.
Your first visit is built to give you an answer the same day, not just another referral.
ACL recovery isn't a straight line — but it is predictable. These are the phases nearly every reconstructed knee moves through on the way back to sport.
The first six weeks are about calming the joint, protecting the new graft, and getting the knee fully straight. Full extension early is non-negotiable.
Targeted physical therapy rebuilds the hamstring and quad strength the graft depends on, plus the neuromuscular control that protects you from re-injury.
Return-to-sport clearance is earned, not given by the calendar. We use objective strength and hop testing to confirm the knee is ready before you go back to cutting and pivoting.
We talk through the risks and benefits with every ACL patient — informed consent is a conversation, not a form.
Every reconstruction carries a small set of standard surgical risks. We screen, prepare, and monitor for these on every patient.
A few risks are specific to ACL reconstruction itself. We discuss each in detail so you can weigh them against the benefits.
ACL reconstruction is a sports-medicine subspecialty, and our team treats it that way. The surgeons listed below operate on ACLs every week, train in the same fellowships that produced the team physicians for major professional and collegiate programs, and follow their patients personally from the first visit through full return to sport. You don't get handed off to a different doctor for each step.
Tore my ACL playing rec-league soccer at 34 and was convinced my season was over for good. Dr. Longacre walked me through every graft option, did the reconstruction, and I was back to non-contact training by month seven. Cleared for games at ten months. Couldn't ask for more.
Book an ACL evaluation at any of our eight Los Angeles–area offices. Same-week MRI available through our imaging partners.
