Hearing the pop and feeling your knee give out is a moment athletes describe with remarkable consistency — and it’s a moment that often marks an ACL tear. As an orthopedic surgeon specializing in sports medicine at Grossmont Orthopaedic Medical Group, I see ACL injuries throughout the year from patients across the San Diego area. They happen to high school athletes, weekend warriors, and professional competitors alike. The injury is serious, but with the right treatment and a committed rehabilitation plan, the majority of my patients return to their sport at or near their previous level.

What Is the ACL?

The anterior cruciate ligament (ACL) is one of four major ligaments that stabilize the knee. It runs diagonally through the center of the joint, connecting the femur to the tibia, and its primary job is to prevent the tibia from sliding forward and rotating beneath the femur. Without it, the knee feels unstable — especially during cutting, pivoting, and landing movements.

Unlike a muscle pull that heals with rest, a completely torn ACL does not knit itself back together. The ligament’s ends retract and the tissue loses its structural integrity, which is why surgery is often required for patients who want to return to high-demand activities.

How ACL Tears Happen

The majority of ACL tears — roughly 70% — are non-contact injuries. There is no collision; instead, the mechanism is a sudden deceleration combined with a cutting or pivoting movement. The classic scenario: planting the foot to change direction, then pushing off explosively while the knee rotates. Basketball, soccer, football, and skiing are particularly high-risk sports.

One statistic worth knowing: women tear their ACL five to six times more frequently than men in equivalent sports. The reasons are multifactorial — hormonal influences on ligament laxity, wider pelvis anatomy altering the angle of force through the knee, and differences in neuromuscular activation patterns all play a role. This disparity is one reason ACL prevention programs focused on landing mechanics and hip strengthening have become a standard part of women’s athletic training.

Recognizing the Symptoms

Most patients know immediately that something significant has happened:

A loud or felt pop at the time of injury
Immediate pain severe enough to stop play
Rapid swelling — a hemarthrosis (blood in the joint) that typically develops within two to four hours
Inability to continue activity or bear full weight
A sense of instability — “the knee shifted” or “it won’t hold me”

Occasionally patients walk off the field and think they simply twisted the knee. If swelling is significant and instability persists, an ACL tear should be on the diagnostic list regardless of initial walking ability.

Immediate First Aid

In the first 24–48 hours after suspected ACL injury:

Ice the knee for 10–15 minutes every few hours — do not apply ice directly to skin
Apply an ACE compression wrap to help control swelling
Elevate the leg above heart level when resting
Use crutches if weight bearing is painful
Avoid immobilizing the knee in full extension with a rigid splint — gentle motion actually helps

Seek evaluation within a few days. An MRI will confirm the diagnosis and identify any associated injuries — meniscus tears or collateral ligament injuries occur alongside ACL tears in a meaningful percentage of cases.

Treatment Options: Surgery vs. Non-Surgical

Who Can Be Treated Non-Surgically?

Non-surgical management is a reasonable choice for patients who are older, have lower activity demands, or are willing to permanently modify their activities to avoid cutting and pivoting sports. Physical therapy focused on strengthening the hamstrings and hip stabilizers can provide enough functional stability for daily life and low-demand recreation. That said, repeated episodes of giving way can damage cartilage and menisci over time, so the decision deserves careful discussion.

ACL Reconstruction for Active Patients

For patients who want to return to cutting and pivoting sports, ACL reconstruction is the standard of care. The torn ligament cannot be reattached — instead, a new ligament is constructed using a tendon graft. Common graft choices include:

Patellar tendon (bone-patellar tendon-bone) — historically the gold standard for athletes; strong bony fixation, longer rehabilitation
Hamstring tendon — strong, reliable, with less anterior knee pain than patellar tendon in many patients
Quadriceps tendon — increasingly popular, excellent strength characteristics
Allograft (donor tissue) — appropriate for lower-demand patients; avoids donor-site morbidity but carries slightly higher re-tear rates in young high-demand athletes

Graft selection is individualized. I discuss the options with each patient based on age, sport, activity level, and surgical history.

Recovery and Return to Sport

ACL recovery is a commitment. The biological process of graft incorporation — ligamentization — takes months, and returning to sport too soon before the graft has matured is a leading cause of re-injury. My program is built around functional milestones, not just time on the calendar.

Weeks 0–2: Swelling control, quad activation, range-of-motion work. Do not immobilize — early motion is protective.
Weeks 2–12: Progressive strengthening of the quadriceps, hamstrings, and hip stabilizers. Stationary cycling, pool walking.
Months 3–6: Running, agility work, proprioception training.
Months 6–12: Sport-specific training, return-to-sport testing. Full clearance based on symmetry testing, not the calendar alone.

Most patients return to sport between six and twelve months. Rushing that timeline meaningfully increases re-tear risk, so patience through the later phases is genuinely worthwhile.

Frequently Asked Questions

Do all ACL tears require surgery?

No. Patients with lower activity demands — particularly older individuals who do not participate in cutting and pivoting sports — can often function well without surgery using physical therapy and activity modification. Surgery is generally recommended for younger, active patients who want to return to sport and for patients of any age who experience functional instability affecting their daily life. We discuss the options carefully together based on your specific goals.

When is the best time to have ACL reconstruction?

We typically wait until the acute swelling has resolved and range of motion has recovered — usually two to six weeks after injury. Operating on a swollen, stiff knee increases the risk of postoperative stiffness. Working with a physical therapist during this “prehabilitation” period and arriving at surgery with a well-functioning quad makes a meaningful difference in outcomes.

Can I prevent an ACL tear?

ACL prevention programs — particularly the FIFA 11+ and PEP programs — have strong evidence behind them. They focus on landing mechanics, hip and hamstring strengthening, and neuromuscular control. Athletes, especially young women in soccer and basketball, benefit meaningfully from these programs. They won’t eliminate all risk, but they demonstrably reduce it. Our sports medicine team can discuss sport-specific prevention strategies at your visit.

How do I make an appointment to have my knee evaluated?

Call Grossmont Orthopaedic Medical Group at (619) 462-3131 or request an appointment online. We serve patients throughout San Diego, La Mesa, El Cajon, Santee, and the surrounding communities. If you have recent imaging, bring those records to your first visit — it helps us move quickly toward an accurate diagnosis and treatment plan.

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ACL Tear Treatment in San Diego: Surgery, Recovery, and Return to Sport