2. Autologous semitendinosus tendon
graft could function as a meniscal
transplant
Knee Surgery, Sports Traumatology, Arthroscopy (KSSTA)
https://doi.org/10.1007/s00167-021-06606-8
Date of publication- June 2021.
Erik Rönnblad, Pierre Rotzius and Karl Eriksson
Capio Artro Clinic, Stockholm Sports Trauma Research Center/Karolinska Institutet,
Valhallavägen, Stockholm, Sweden.
3. Introduction
• Menisci were defined in 1897 as “functionless remnants of leg muscle
origin”, today, they are considered as structures of fundamental
importance for maintaining the integrity of the knee joint homeostasis.
• Menisci which are fibro-cartilagenous structures, improve the congruence
of the hyaline articular surfaces and play a most important role in load
distribution.
• After a meniscal lesion, the golden rule, now, is to save as much meniscus
as possible and only the meniscus tissue that is identified as unrepairable
should be excised.
4. • Removal of meniscal tissue has been linked to poor outcome and
increased risk of osteoarthritis.
• The reason being decreased tibiofemoral contact surface and increased
contact pressures.
• Post medial menisectomy the contact pressures of the medial side
increase by 100% and of the lateral side increased by 200 to 350%.
• Post menisectomy the treatment options are surgical and nonsurgical, the
nonsurgical being pharmacological and non pharmacological.
5. • The non pharmacological options include physiotherapy, unloading with
crutches or braces, insoles, activity modification and weight loss.
• The surgical management involves substituting the meniscus with either
autografts, allografts or scaffolds. (Synthetic and bio)
• The problems with Meniscal Allograft Transplantation (MAT) were cost and
availability of same size meniscus along with risk of disease transmission,
risk of graft failures due to ruptures, shrinkage, limited cellular infiltration
and poor mechanical properties .
6. • Autografts are biocompatible, no need of processing, no additional monetary
expense and no disease transmission.
• Tendon tissue has same orientation of type 1 collagen fiber bundles as the
peripheral half of meniscus suggesting that it has potential for meniscus
replacement.
• Semitendinosus which has been used routinely for ACL reconstruction has a
lower donor site morbidity and can regenerate after its harvest.
• Tendon derived stem cells in the semitendinosus tendon and the synovium
derived mesenchymal stem cells which covers the meniscus has
fibrochondrogenesis ability.
7. Aim of the study
• Semitendinosus graft can function as a meniscal transplant after total or
subtotal menisectomy.
• Patients receiving neomeniscus with semitendinosus tendon experiences
less post meniscus symptoms.
8. Materials and Methods
• Institute ethical clearance was obtained. Jan 2018 to June 2020.
Inclusion criteria-
• 20-50 years.
• Previous history of total or subtotal menisectomy, medial or lateral.
• No significant osteoarthritis. (Ahlback 0,1)
• No smoking.
• Complaints of post menisectomy symptoms like medial and lateral joint
line pain on weight bearing.
9. Surgical technique
Performed by a senior author
• The harvested SemiT was imbedded in Vancomycin.
• If ACL insufficiency present- ACLR was carried.
• Remnants of the native meniscus were debrided, menisco-capsular
junction was debrided to obtain fresh bleeding surface.
• Pie crust of the MCL done for medial side if necessary.
Post operative course:
• PWBCW for 6 weeks.
• Hinged knee brace with ROM up to 30 degrees for 3 weeks.
• Up to 60 for subsequent 3 weeks, and 90 degrees for the next two weeks.
10. • Graft harvested was folded over it
self, the free ends stitched using
Chinese finger trap technique.
• The folded end stitched with fiber
wire to hold the two ends
together.
• The length varied from 12 to 15
and diameter 6 to 7cm.
• Tunnels were drilled for root
using guide and flip cutter.
• The ends were secured in the
tunnels and the body repaired to
capsule using outside in and
inside out repair.
11. Analysis
• Outcomes were measured at 3, 6, 12 months postoperatively.
• Patients reported outcome measures like- Knee injury and osteoarthritis
and outcome score (KOOS), Lysholm score, and Tenger score.
• MRI at similar intervals, to look for transplant integrity.
• Clinical assessment- ROM, tenderness, effusion, laxity.
• Because of lower sample size the results are only presented in a
descriptive fashion.
13. • There was improvement in Lysholm score and KOOS
score at 12 months follow up.
14. Discussion
• The most important finding of the study
was that early results indicate
promising potential for the use of
semitendinosus tendon as a meniscus
transplant with most patients
experienced an improvement in terms
of weight bearing pain and quality of
life
• The early follow-up data indicate that
the transplant could survive, transform
and remodel to a meniscus-like
structure with ingrowth to the
surrounding capsular tissue.
15. Transplant integrity
• MRI scans at 12-month follow-up show signs that the transplant transforms in
shape and becomes more wedge like, with increased signal in most
projections.
• The anchorage of the roots is visible.
16. Conclusion
• The use of autologous semitendinosus tendon as meniscus
transplant seems to be a possible alternative to the methods
used today.
• The patients included so far present improvement in weight
bearing pain and quality of life.
17. Limitations
• The follow-up time is short.
• The cohort is limited in size.
• The patients in this study were not offered a MAT as alternative
treatment.
• To be able to draw a sounder conclusion, more patients need to be
included with a longer follow-uptime.
19. • 5 patients with post-menisectomy complaints, loss of joint space,
ligamentous stable knee, included grade 3 and 4 degenerative
changes (Outerbridge)
• Exclusion criteria are ligamentous instability, and axial mal-
alignment > 15 degrees, infection.
• 5 patients (41 years mean age) lateral meniscus,
semitendinosus(4), patellar tendon, did not exclude mal-alignment
or arthritis.
• At 4 years follow up one pt underwent arthrodesis, 3 underwent
TKR, one had minimal pain in recreational activities.
• Concluded that case selection should include less severe
degenerative changes, and mal-alignment to be corrected.
20.
21. • Single patient, 32 years, medial meniscus post subtotal menisectomy 6
months post op,
• For implanting a meniscal implant a intact meniscal rim is necessary to
prevent extrusion,
• 5 months post op, second look arthroscopy identified graft invaded by
synovial tissue and a collagen meniscal implant was used and fixed to
the meniscal wall formed by the graft, at two years no complaints.
• Tendon graft complemented with meniscal implant.
