What did the study look at?
The patellar tendon runs from the lower end of the kneecap to a bony bump on the shinbone and is part of the mechanism that straightens the knee (extension). According to the authors, chronic, long-standing ruptures are difficult to treat because the tendon thins, scar tissue forms and the tendon pulls upwards. This publication presents a reconstruction technique for such ruptures using an Achilles tendon allograft (tissue from a donor). It is a technical note presented with video, not a comparative study.
How was it done?
The technique was performed on a 46-year-old woman who had previously had anterior cruciate ligament reconstruction. After a fall two years earlier she had increasing knee pain, could not actively straighten the knee fully (an extensor lag of 30–40 degrees) and had a high-riding kneecap (patella alta) on X-ray. Non-operative treatment had not helped.
The main steps of the operation are described as follows:
- A lengthwise incision was made over the front of the knee, the ruptured tendon was found and the scarred tissue was cleared.
- Three 3.5 mm holes were drilled in the lower end of the kneecap for 5.5 mm bio-composite anchors, and the native tendon was secured with sutures while the knee was fully straight.
- An Achilles tendon graft with a bone block was prepared; the bone block was fixed with a metal screw in a tunnel 10 mm wide and 2 cm deep just below the bump on the shinbone.
- The graft was folded upwards over the repair and stitched to the native tendon with suture tape, and its lower end was reinforced with an additional anchor.
The authors state that the patient's own tissue (autograft) was not used because of her earlier surgery and the risk of problems at the donor site. The procedure took about 90 minutes.
What did it find?
After surgery the patient wore a brace locked straight, was allowed to bear weight as tolerated and began physiotherapy on the first day. At six months she had full extension and 120 degrees of flexion and had returned to daily activities without walking aids. X-rays showed a healed graft and restored kneecap height. The authors report that similar cases at their institution have also shown graft incorporation with few complications.
In their discussion, citing earlier biomechanical studies, the authors note that repairs with an Achilles graft and bone block nearly double the load to failure compared with primary repair alone (from under 400 N to 750 N).
The authors' conclusion
The authors consider Achilles allograft augmentation a reliable option for chronic patellar tendon ruptures, particularly when the tendon is thinned or retracted, as it avoids donor-site problems and allows strong fixation and early rehabilitation. It should be noted that this conclusion is based on a technique description shown in a single patient.
Reference
Alnemri AG, Vadhera AS, Kumar R, Swindell H, Gürsoy S, Verma NN, Chahla J. (2025). Patellar Tendon Reconstruction With Achilles Allograft: A Technical Note. Video Journal of Sports Medicine, 5(6):26350254251368929. Licence: CC BY 4.0.
DOI: 10.1177/26350254251368929
Free full text: PMC12686371
This article summarises a published scientific paper for general information; it does not replace an examination or a personal medical assessment. Please consult your doctor about your symptoms.
