ACL Reconstruction — Patellar Tendon Graft

Why this approach — at MOS

The BPTB graft is our default recommendation for competitive athletes in cutting and pivoting sports — particularly those playing at high school varsity, collegiate, or professional levels — when the anatomy is appropriate and the patient is willing to accept the anterior knee tradeoffs. The mechanical advantages of bone-to-bone healing, graft stiffness, and decades of outcome data make it a reliable choice for patients whose performance demands are the highest.

That said, we do not use BPTB in every patient. A competitive distance runner with no pivoting demands, pre-existing anterior knee pain, and a job that involves daily kneeling would be better served by a quadriceps or hamstring autograft. Patient-specific anatomy matters too — we examine patellar tendon width on MRI before recommending this graft, because harvesting the middle third of a narrow tendon leaves inadequate remaining tissue.

Tunnel placement is performed with anatomic precision. The femoral tunnel is drilled through an anteromedial portal technique to achieve true anatomic placement on the medial wall of the lateral femoral condyle, rather than the more vertical tunnels produced by transtibial drilling. Anatomic tunnel placement restores the original ACL's isometry and reduces the risk of graft impingement and residual rotational laxity.

Patients who serve Bethesda, Germantown, and Rockville through our three MOS offices have access to our in-house physical therapy program, which is coordinated with our surgical protocols from the day of surgery.

Who is a candidate?

Indications

• Competitive athletes — high school, collegiate, professional — who need the highest-confidence graft option for return to cutting and pivoting sports
• Patients with ligamentous laxity where graft stiffness is a priority
• Patients willing to accept the donor-site tradeoffs (anterior knee pain, kneeling discomfort) in exchange for the mechanical advantages of bone-to-bone healing
• Primary ACL reconstruction in young patients (under 25) with high activity demands
• Patients with anatomic considerations favoring BPTB (adequate patellar tendon width, good patellar bone stock)

Contraindications / Less Preferred Situations

• Patients whose occupation or lifestyle requires frequent kneeling (clergy, flooring tradespeople, certain athletes) — anterior knee pain with kneeling is a documented donor-site complication
• Patients with pre-existing anterior knee pain or patellar tendinopathy — harvesting the patellar tendon can worsen baseline symptoms
• Skeletally immature patients where bone plug placement near the growth plates requires careful planning
• Revision ACL reconstruction where the patellar tendon was used in the prior surgery — a different graft source is preferred
• Patients with small patellar tendons (width less than 25 mm) where harvesting the middle third would leave inadequate tissue on each side

Conservative Treatment First

Not every ACL tear requires surgery. Lower-demand patients — those who are sedentary, do not pivot or cut, and do not experience functional giving-way — may manage successfully with physical therapy and activity modification. At Maryland Orthopedic Specialists, patients presenting with an ACL tear are offered a supervised physical therapy trial before committing to reconstruction when their functional demands make non-surgical management reasonable.

For competitive athletes, however, the case for reconstruction is typically clear: continued participation in pivoting sports with an ACL-deficient knee risks secondary meniscal damage and cartilage injury that can cause long-term problems. When surgery is recommended, graft selection becomes the central discussion.

The procedure

What Is ACL Reconstruction with a Patellar Tendon Graft?

Bone-patellar tendon-bone (BPTB) ACL reconstruction uses the middle third of the patellar tendon, with a block of bone at each end, to replace the torn ACL. The bone plugs heal directly into the femoral and tibial tunnels, providing strong, early fixation. It is widely regarded as the gold standard graft for competitive athletes due to its mechanical strength and reliable outcomes.

The patellar tendon connects the bottom of the kneecap (patella) to the front of the tibia (shin bone). Its middle third — typically 9–10 mm wide and 25–30 mm long — is harvested with a small rectangular block of patellar bone at one end and a block of tibial bone at the other. This combination of tendon and bone at each end is what defines the BPTB graft and is the key to its primary advantage: bone-to-bone healing.

When the bone plugs are seated inside the bone tunnels drilled in the femur and tibia, they heal the same way a fracture heals — through direct bony incorporation. This process is typically complete by 6–8 weeks and is faster and more mechanically reliable than the soft tissue-to-bone healing that occurs with hamstring or quadriceps tendon grafts. The result is earlier, more confident early fixation, which supports a more aggressive rehabilitation progression in athletes motivated to return to sport.

The BPTB graft has decades of clinical data behind it. It consistently produces low re-rupture rates in competitive athletes and has been the benchmark against which all other graft options are measured in comparative studies.

What Happens During Patellar Tendon ACL Reconstruction?

The procedure is performed as outpatient surgery under general or spinal anesthesia, typically lasting 60–90 minutes.

Step 1 — Graft harvest. A vertical incision approximately 3–4 cm long is made over the front of the knee, centered on the patellar tendon. The surgeon identifies the middle third of the tendon and cuts the graft with a bone plug of patellar bone superiorly and a bone plug of tibial bone inferiorly. The graft is prepared on the back table — the bone plugs are sized, shaped, and drilled to accept fixation hardware. Drill holes are placed in the donor sites to encourage bony fill.

Step 2 — Arthroscopic joint inspection. Small arthroscopic portals are made at the knee, and the joint is inspected through the camera. Any meniscus tears or cartilage damage found at this stage is addressed. The torn ACL remnants are debrided using a shaver.

Step 3 — Tunnel drilling. A guide pin is placed at the anatomic tibial ACL footprint and the tibial tunnel is drilled. The femoral tunnel is drilled through the tibial tunnel or via an accessory anteromedial portal to achieve accurate anatomic placement. Tunnel position is confirmed arthroscopically.

Step 4 — Graft passage. The prepared BPTB graft is pulled through the tibial tunnel and into the femoral tunnel using a passing suture. The patellar bone plug seats in the femoral tunnel and the tibial bone plug seats in the tibial tunnel.

Step 5 — Fixation. Interference screws are driven into each tunnel alongside the bone plugs, compressing the bone plug against the tunnel wall. This provides immediate rigid fixation. Graft tension is confirmed and the knee is cycled through full range of motion to ensure smooth tracking and full extension.

Step 6 — Closure. The harvest site and portal incisions are closed with absorbable sutures. A compressive wrap and a hinged knee brace are applied. Most patients are discharged home within 2–3 hours.

Recovery timeline

Frequently Asked Questions