Semitendinosus Autograft vs Meniscal Allograft in Post-Meniscectomy Syndrome

Official title

A Stratified, Partially Randomized Study Comparing Autologous Semitendinosus Tendon Graft and Meniscal Allograft Transplantation in Young Adults With Post-Meniscectomy Syndrome

Overview

This multicenter, stratified, partially randomized clinical trial aims to compare autologous semitendinosus tendon graft and meniscal allograft transplantation (MAT) in young adults with post-meniscectomy syndrome. The meniscus plays a critical role in load distribution, shock absorption, and joint stability. After meniscectomy, insufficient meniscal tissue often leads to persistent pain, swelling, and functional decline, increasing the risk of early osteoarthritis. Two reconstructive strategies are clinically available: MAT provides immediate biomechanical function but requires donor matching and carries higher costs, while autologous tendon graft offers stable supply and no immunologic risk but lacks long-term clinical validation. In this study, 40 patients aged 18-45 years will be enrolled. Participants will be allocated into four groups (randomized MAT, randomized autograft, patient-preference MAT, patient-preference autograft). All procedures will use a two-tunnel fixation technique with additional internal brace support. The primary endpoint is the improvement in KOOS (Knee Injury and Osteoarthritis Outcome Score) at 24 months postoperatively. Secondary endpoints include MRI-based assessment of graft morphology and extrusion, reoperation rate, complications, patient satisfaction, and return-to-sport time. This trial will provide critical evidence regarding the comparative effectiveness and feasibility of tendon autograft versus meniscal allograft in real-world clinical settings, potentially informing surgical decision-making and future treatment guidelines for post-meniscectomy syndrome.

Detailed description

Post-meniscectomy syndrome represents a challenging condition in young adults, characterized by persistent pain, swelling, and functional impairment after partial or subtotal meniscectomy. The lack of sufficient meniscal tissue predisposes patients to abnormal tibiofemoral loading and early onset osteoarthritis. Current reconstructive options remain limited, and there is no consensus on the optimal surgical strategy.

Meniscal allograft transplantation (MAT) has been the most widely accepted method, offering immediate restoration of meniscal morphology and load-distributing capacity. However, MAT is constrained by donor availability, graft costs, and local regulations. In contrast, autologous tendon grafts-most commonly using semitendinosus-are readily available, carry no risk of rejection, and reduce cost barriers. Early biomechanical and translational studies suggest that autologous tendon grafts may adapt to meniscal-like properties, yet long-term clinical data remain scarce.

This trial employs a stratified, partially randomized design to balance methodological rigor with patient autonomy and ethical feasibility. Participants are assigned to autologous tendon graft or MAT either through randomization or patient preference, allowing assessment of outcomes under both controlled and real-world conditions. All procedures are standardized across participating centers, utilizing a two-tunnel fixation technique and augmented with an internal brace (Fibertape) to enhance graft stability.

Outcomes will be assessed over 24 months, including validated patient-reported measures (KOOS, IKDC, Tegner), MRI-based graft evaluation (volume, signal, extrusion, morphology), reoperation rates, complications, satisfaction, and return-to-sport. By integrating randomized comparison with pragmatic elements, this study aims to generate clinically applicable evidence on the relative benefits and limitations of autologous tendon graft versus MAT. The findings are expected to inform surgical decision-making, optimize patient outcomes, and guide future treatment recommendations for young patients suffering from post-meniscectomy syndrome.

Interventions

• Procedure Autologous Semitendinosus Tendon Graft
  Meniscal reconstruction will be performed using autologous semitendinosus tendon harvested from the ipsilateral leg. The graft diameter must be at least 6 mm. A two-tunnel fixation technique will be employed, securing the graft to the tibial plateau at the anatomic meniscal root sites. The graft will be shaped and positioned to mimic the native meniscal contour. Fibertape internal brace augmentation will be added to enhance fixation strength and graft stability. If concomitant anterior cruciate
• Procedure Meniscal Allograft Transplantation (MAT)
  Meniscal allograft transplantation will use size-matched, fresh-frozen allograft menisci prepared according to institutional tissue bank standards. Grafts will be fixed using a two-tunnel bone plug technique, restoring the anatomic root insertions. The allograft will be centrally positioned within the tibiofemoral compartment, and centralization sutures may be added at the discretion of the operating surgeon. All procedures will be standardized across participating centers, and postoperative reh

Primary outcome measures

• Knee Injury and Osteoarthritis Outcome Score [Time frame: Baseline, 6, 12, and 24 months after surgery (primary analysis at 24 months)]

Secondary outcome measures (7)

• MRI-Based Graft Evaluation [Time frame: 12 and 24 months postoperatively]
• IKDC (International Knee Documentation Committee) Subjective Knee Evaluation [Time frame: Baseline, 6, 12, and 24 months after surgery]
• Tegner Activity Scale [Time frame: Baseline, 6, 12, and 24 months after surgery]
• Reoperation Rate [Time frame: Up to 24 months postoperatively]
• Complications [Time frame: Within 24 months after surgery]
• Patient Satisfaction [Time frame: 12 and 24 months postoperatively]
• Return to Sport Time [Time frame: Up to 24 months postoperatively]

Eligibility criteria

Inclusion criteria

• Adults aged 18 to 45 years

History of partial meniscectomy > 6 months prior to enrollment

Symptomatic post-meniscectomy syndrome (knee pain, swelling, or functional decline)

MRI showing cartilage status ≤ Outerbridge grade 2

Knee joint stability (or stabilized during the index surgery)

Body mass index (BMI) < 30

Willingness to provide written informed consent

Exclusion criteria

Tibial slope > 16°

Radiographic or arthroscopic evidence of advanced cartilage degeneration (Outerbridge > 2 or ICRS ≥ 3)

Presence of inflammatory arthritis or systemic inflammatory joint disease

History of cartilage repair surgery

Malalignment > 5° not corrected

Untreated ligamentous instability

Any other condition judged by the investigator to compromise study participation or outcomes

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Taiwan · 1 center

• Chang Gung memorial hospital, Taoyuan, taoyuan 333 — Taoyuan City

Publications

• Seitz AM, Leiprecht J, Schwer J, Ignatius A, Reichel H, Kappe T. Autologous semitendinosus meniscus graft significantly improves knee joint kinematics and the tibiofemoral contact after complete lateral meniscectomy. Knee Surg Sports Traumatol Arthrosc. 2023 Jul;31(7):2956-2965. doi: 10.1007/s00167-022-07300-z. Epub 2023 Jan 5. PMID 36604322
• Ronnblad E, Rotzius P, Eriksson K. Autologous semitendinosus tendon graft could function as a meniscal transplant. Knee Surg Sports Traumatol Arthrosc. 2022 May;30(5):1520-1526. doi: 10.1007/s00167-021-06606-8. Epub 2021 Jun 8. PMID 34100999

Identifiers

NCT: NCT07204587 · ChangGungMH MeniscusTransplant

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗