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Changes in Contact Area in Meniscus Horizontal Cleavage Tears Subjected to Repair and Resection

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Purpose: To assess the changes in tibiofemoral contact pressure and contact area in human knees with a horizontal cleavage tear before and after treatment. Methods: Ten human cadaveric knees were tested. Pressure sensors were placed under the medial meniscus and the knees were loaded at twice the body weight for 20 cycles at 0°, 10°, and 20° of flexion. Contact area and pressure were recorded for the intact meniscus, the meniscus with a horizontal cleavage tear, after meniscal repair, after partial meniscectomy (single leaflet), and after subtotal meniscectomy (double leaflet). Results: The presence of a horizontal cleavage tear significantly increased average peak contact pressure and reduced effective average tibiofemoral contact area at all flexion angles tested compared with the intact state (P < .03). There was approximately a 70% increase in contact pressure after creation of the horizontal cleavage tear. Repairing the horizontal cleavage tear restored peak contact pressures and areas to within 15% of baseline, statistically similar to the intact state at all angles tested (P < .05). Partial meniscectomy and subtotal meniscectomy significantly increased average peak contact pressure and reduced average contact area at all degrees of flexion compared with the intact state (P < .05). Conclusions: The presence of a horizontal cleavage tear in the medial meniscus causes a significant reduction in contact area and a significant elevation in contact pressure. These changes may accelerate joint degeneration. A suture-based repair of these horizontal cleavage tears returns the contact area and contact pressure to nearly normal, whereas both partial and subtotal meniscectomy lead to significant reductions in contact area and significant elevations in contact pressure within the knee. Repairing horizontal cleavage tears may lead to improved clinical outcomes by preserving meniscal tissue and the meniscal function. Clinical relevance: Understanding contact area and peak contact pressure resulting from differing strategies for treating horizontal cleavage tears will allow the surgeon to evaluate the best strategy for treating his or her patients who present with this meniscal pathology.
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Changes in Contact Area in Meniscus Horizontal
Cleavage Tears Subjected to Repair and Resection
Brandon S. Beamer, M.D., Kempland C. Walley, B.Sc., Stephen Okajima, B.Sc.,
Ohan S. Manoukian, B.Sc., Miguel Perez-Viloria, M.D., Joseph P. DeAngelis, M.D.,
Arun J. Ramappa, M.D., and Ara Nazarian, Ph.D.
Purpose: To assess the changes in tibiofemoral contact pressure and contact area in human knees with a horizontal
cleavage tear before and after treatment. Methods: Ten human cadaveric knees were tested. Pressure sensors were
placed under the medial meniscus and the knees were loaded at twice the body weight for 20 cycles at 0,10
, and 20of
exion. Contact area and pressure were recorded for the intact meniscus, the meniscus with a horizontal cleavage tear,
after meniscal repair, after partial meniscectomy (single leaet), and after subtotal meniscectomy (double leaet).
Results: The presence of a horizontal cleavage tear signicantly increased average peak contact pressure and reduced
effective average tibiofemoral contact area at all exion angles tested compared with the intact state (P<.03). There was
approximately a 70% increase in contact pressure after creation of the horizontal cleavage tear. Repairing the horizontal
cleavage tear restored peak contact pressures and areas to within 15% of baseline, statistically similar to the intact state
at all angles tested (P<.05). Partial meniscectomy and subtotal meniscectomy signicantly increased average peak
contact pressure and reduced average contact area at all degrees of exion compared with the intact state (P<.05).
Conclusions: The presence of a horizontal cleavage tear in the medial meniscus causes a signicant reduction in contact
area and a signicant elevation in contact pressure. These changes may accelerate joint degeneration. A suture-based
repair of these horizontal cleavage tears returns the contact area and contact pressure to nearly normal, whereas both
partial and subtotal meniscectomy lead to signicant reductions in contact area and signicant elevations in contact
pressure within the knee. Repairing horizontal cleavage tears may lead to improved clinical outcomes by preserving
meniscal tissue and the meniscal function. Clinical Relevance: Understanding contact area and peak contact pressure
resulting from differing strategies for treating horizontal cleavage tears will allow the surgeon to evaluate the best strategy
for treating his or her patients who present with this meniscal pathology.
The meniscus serves to dissipate force across the
articular surface by increasing the contact area
between the concave distal femoral condyle and the
relatively at tibial plateau.
1,2
Multiple studies have
shown that removal of meniscal tissue lowers the
contact area and increases contact pressure.
3-7
It is
thought that the resulting elevated tibiofemoral contact
pressure leads to degenerative changes of the articular
cartilage.
8,9
Tears in the meniscus compromise the load distribu-
tion function of the meniscus. In the clinical setting, the
torn tissue often is removed to alleviate immediate
symptoms; however, tissue removal predisposes the
knee to arthritis.
3
Studies also show that greater
amounts of tissue removal are associated with worse
long-term outcomes in patients.
10
For this reason, ap-
proaches that preserve meniscal tissue and potentially
prevent future degeneration have been growing.
2,11-13
Most biomechanical studies have concentrated on
vertical or radial tears, with little in the literature pub-
lished on horizontal cleavage tears (HCTs) until
recently. HCTs divide the meniscus into an upper and
lower lamina, relatively parallel to the tibial plateau.
They are among the most common meniscal tears
14
and
From the Center for Advanced Orthopaedic Studies (B.S.B., K.C.W., S.O.,
O.S.M., M.P-V., A.N.) and Department of Orthopaedic Surgery (B.S.B.,
K.C.W., S.O., O.S.M., M.P-V., J.P.D., A.J.R., A.N.), Beth Israel Deaconess
Medical Center, Harvard Medical School, Boston, Massachusetts, U.S.A.
J.P.D., A.J.R., and A.N. contributed equally to this work and should be
considered coesenior authors.
The authors report the following potential conicts of interest or sources of
funding: The Orthopaedic Research and Education Foundation (OREF) in
conjunction with the Dr. Dane and Mary Miller Endowment Fund funded
this study. Ceterix provided devices for the study.
Received March 2, 2016; accepted September 12, 2016.
Address correspondence to Ara Nazarian, Ph.D., Center for Advanced
Orthopaedic Studies, Beth Israel Deaconess Medical Center, 330 Brookline
Avenue, RN115, Boston, MA 02215, U.S.A. E-mail: anazaria@bidmc.
harvard.edu
Ó2016 by the Arthroscopy Association of North America
0749-8063/16185/$36.00
http://dx.doi.org/10.1016/j.arthro.2016.09.004
Arthroscopy: The Journal of Arthroscopic and Related Surgery, Vol -,No-(Month), 2016: pp 1-8 1
have been associated with degradation of knee carti-
lage.
15
The presence of a horizontal tear may cause
symptoms leading to arthroscopic intervention. HCTs
frequently are treated with partial meniscectomy
(single leaet resection), subtotal meniscectomy
(resection of both leaets), or conservative treatment.
Haemer et al.
4
studied the impact of partial and subtotal
meniscectomy for small and large horizontal tears in a
goat model and showed that both partial and subtotal
meniscectomy led to signicant elevations in contact
pressure for large tears. A recent systematic review
examined all reported outcomes after HCT repair
attempts and showed a success rate similar to that
reported for other tear types that are repaired more
commonly.
16
Subsequently, 2 additional clinical studies
reported success rates of more than 90% for HCT
repair, raising the question related to the biomechanical
rationale for such repairs.
17,18
The specic aim of this study was to assess the
changes in tibiofemoral contact pressure and contact
area in human knees with a HCT before and after
treatment. We hypothesized that resection of one or
both lamina of a large HCT in the medial meniscus leads
to elevation in contact pressures in the knee, which
may be mitigated through repair.
Methods
Preparation, Repair, and Loading
Ten intact fresh frozen human cadaveric knees
(donor weight 66 11 kg, donor height 169 8.1 cm,
donor age 67 7 years, 5 male and 5 female) were
acquired (Medcure, Providence, RI) and evaluated by
an orthopaedic surgeon (B.S.B.) to exclude those with
grade 3 or 4 cartilage lesions (no specimens were
excluded). The skin and subcutaneous fat were
removed from the specimens, followed by the under-
lying muscle and extensor mechanism. Care was taken
to preserve the integrity of the joint capsule, collateral
ligaments, and cruciate ligaments. On gross examina-
tion, each showed no evidence of signicant arthritis or
meniscal tearing. The femur and tibia were cut 10 cm
from the joint line.
To gain access to the medial compartment, an
osteotomy was performed at the femoral origin of the
medial collateral ligament (MCL) so that the supercial
and deep bers could be taken down as a continuous
sleeve. The bone was then repaired in situ with a
50-mm 3.5-mm cortical screw and washer. This
technique was chosen because it does not affect tibio-
femoral contact pressures.
3
To allow the testing lm to
lie at on the tibial plateau, an incision was made
beneath the anterior and posterior horns of the
meniscus along the joint line, and approximately 1 cm
of the coronary ligaments was resected without
disrupting the meniscal root, meniscofemoral liga-
ments, or the remaining capsular attachments.
A calibrated pressure sensor (4010N; 44 mm
68 mm 0.2 mm, 422 sensels, 25 sensels/cm
2
density;
Tekscan, South Boston, MA) was wrapped in adhesive
lm (Tegaderm, Nexcare; 3M, Saint Paul, MN) and
was inserted under the medial meniscus ush with
the tibial plateau. Sensors were calibrated for repeat-
ability according to manufacturersprotocol.The
sensor was secured with 2 #1 PDS sutures (Poly-
diaxone suture; Ethicon, Somerville, NJ) placed
through the periphery of the sensor and the perios-
teum of the tibia.
3
Before insertion, the pressure sensor was calibrated
with a loading frame (Instron 8511; Instron, Norwood,
MA) with its native load cell (2500 N limit). Three
calibration pressures within the expected minimum
and maximum tibiofemoral contact pressure ranges of
the study were applied, and the entire matrix area of
the sensor was loaded to ensure precise calibration.
The sensors were instructed to collect pressure data at
a sampling rate of 100 Hz during cyclic loading
experiments and at a sampling rate of 4 Hz during the
ramped loading tests to ensure a consistent peak
pressure measurement. The ramped loading tests also
acquired pressure data at 4 Hz for 10 seconds once the
maximum load was achieved. Data acquisition for
each specimen was nished after the ramped loading
tests.
The tibiofemoral loading protocol was based on the
work of Bedi et al.,
3
in which the authors analyzed
tibiofemoral contact pressures for radial tears in
cadaveric lateral menisci. The exion angles were
chosen to recreate the tibiofemoral contact pressure
prole transitioning from stance
3
to normal walking
gait before execution of the swing mechanism, where
load on the meniscus is minimal. Although a mea-
surement at 0best resembles a well-established
loading scheme, load bearing occurs at various exion
angles; thus, additional testing at exion angles of 10
and 20was investigated for potential variations in
loading behaviors surrounding the meniscus.
A simplied testing jig was designed to apply axial
load to the knee joint at varying exion angles. The jig
consisted of 2 boxes to mount the embedded ends of
the proximal femur and the distal tibia. The distal tibia
box was mounted on a 6-degree of freedom (DoF) load
cell (Omega 160; ATI Industrial Automation, Apex,
NC) and a sliding mechanism to allow for the selection
of different exion angles. The testing jig was mounted
on the load cell (2500 N limit) of the load frame
(Instron 8511; Instron). The proximal femoral box was
attached to a ball joint before being connected to the
hydraulic actuator of the load frame (Fig 1). The knee
was placed in the testing jig by potting the tibial and
femoral diaphyses into a block mold with the use of
2B. S. BEAMER ET AL.
polymethylmethacrylate. The polymethylmethacrylate
blocks were placed and secured into the jig, ensuring
the joint line was perpendicular to the mechanical axis
of the mechanical testing system at 0exion angle via
a laser guide (Fig 2). Knees were loaded axially at twice
the body weight and 0exion angle (1310-2437 N),
simulating the average joint reactive force the knee
experiences during normal gait.
19
Axial loads for 10
and 20exion angles were calculated and applied for
the said angles (1290-2400 and 1231-2290 N, respec-
tively). For each testing condition and exion angle,
the knees were loaded axially for 20 cycles at a rate of
1 Hz. The native load cell of the load frame was used to
control the load frame, and the 6DoF load cell was used
to record loads and torques along X (anterior-posterior,
posterior þdirection), Y (medial-lateral, lateral þdi-
rection), and Z (superior-inferior, superior þdirection)
axes. Under these conditions, data were recorded for
average and peak tibiofemoral contact pressures and
contact area in the intact medial meniscus (group 1)
with the jig placed in 0,10
,or20
of exion
respectively (Fig 2), for 20 cycles each, to simulate
various phases of the gait cycle.
19
After the MCL was then taken down, an HCT was
made in the medial meniscus under direct visualization
with a #11 surgical blade just superior to the apex. The
tear extended to within 1 mm of the joint capsule and
extended from the anterior horn to the posterior horn
(Fig 3A) at the approximate midpoint of the meniscus.
Fig 1. An outline of the testing jig with key components and a
left knee mounted onto the jig. (DoF, degree of freedom.)
Fig 2. The tibiofemoral axial loading apparatus employed in this study at 0,10
, and 20settings with a left knee.
HORIZONTAL TEARS AND JOINT CONTACT PRESSURE 3
The location and size of tear were conrmed by visual
inspections. The MCL osteotomy was repaired and the
loading regimen was repeated, and we analyzed
tibiofemoral contact area and pressure for the torn
meniscus and recorded for the varying degrees of
exion (group 2).
Fig 3. The experimental testing states (torn [A], repaired [B], partially resected [C], and fully resected [D]) presented in this
study with a left knee.
4B. S. BEAMER ET AL.
The meniscus was then repaired in an open fashion
with an all-inside, vertical loop technique. Four vertical
loops of 2-0 UHMWPE suture (Teleex, Morrisville,
NC) were spaced evenly along the length of the torn
meniscus (Fig 3B) and tied with surgeons knots. The
sutures were placed via the use of a suture passing
device (NovoStitch; Ceterix Orthopaedics, Menlo Park,
CA). The loading regimen was repeated for the repair
group (group 3). The repair sutures were removed and
the upper leaet resected to within 2 mm of the
meniscal periphery to simulate a partial meniscectomy
and the sample was loaded (group 4) (Fig 3C). Lastly,
the remaining lower meniscal leaet was resected back
to a stable rim (2 mm from capsular attachment) to
complete a subtotal meniscectomy. The loading process
was repeated (group 5) (Fig 3D).
3
During the entire
testing process, the Tekscan sensors were monitored for
crinkling.
Statistical Analysis
Tibiofemoral contact pressures average 6 1.5 MPa
in the medial compartment of normal knees and
7.4 1.5 MPa in knees with the medial meniscus
resected.
3
When these values are used as a guide, a
sample size of 10 was calculated to result in 80%
power to detect a 20% change in contact pressure
based on analysis of variance (nQuery Advisor ver. 7.0;
Statistical Solutions, Saugus, MA). The Shapiro-Wilk
test for normality was used to evaluate the distribu-
tion of the data. When a normal distribution was
assumed, 2-way analysis of variance with the esti-
mated marginal means method and Tukey post-hoc
analysis was performed with group (intact, full-
thickness tear, repair, partial meniscectomy, and sub-
total meniscectomy) and exion angle (0,10
,20
)as
xed factors and contact pressure and contact area as
dependent variables. SPSS software (version 21.0,
Chicago, IL) was used for data analysis. All reported
Pvalues are 2-tailed, and P<.05 was considered
statistically signicant.
Results
The presence of a HCT signicantly increased average
peak contact pressure and reduced effective average
tibiofemoral contact area at 0,10
,20
of exion
compared with the intact state (P<.03) (Fig 4). The
increase in contact pressure was approximately 70%
after creation of the HCT. Repairing the HCT resulted in
peak contact pressures and areas that were restored to
within 15% of baseline, statistically similar to the intact
state at all angles tested (P<.05). Partial meniscec-
tomy, through the removal of the superior leaet,
signicantly increased average peak contact pressure
and reduced average contact area at all degrees of
exion compared with the intact state (P<.05), with
pressures approximating the unresected HCT status.
Although partial meniscectomy decreased the average
contact area and increased the average peak contact
pressure from baseline by a greater amount than the
torn state, the difference between the torn and partial
meniscectomy conditions was not statistically signi-
cant. Compared with the intact and repaired states,
Fig 4. Tibiofemoral contact area (A) along with average
(B) and peak (C) contact pressures for each of the 5 test
states (intact, torn, repaired, partial, and total resection).
Single asterisk (*) denotes difference between intact state
with other states; double asterisk (**) denotes difference
between tear state and other states; and diamond symbol
denotes difference between repaired state and other states.
HORIZONTAL TEARS AND JOINT CONTACT PRESSURE 5
subtotal meniscectomy increased the average peak
contact pressure by more than 100% and decreased the
average tibiofemoral contact area by approximately
50% at all degrees of exion (P<.0001).
Increasing exion angle was associated with
decreased average contact areas by 10% to 15% in the
presence of a tear, repair or meniscectomy, with 20
exion resulting in larger reductions in contact areas. In
the intact state, little difference in average contact area
was observed between 0and 10exion, and a small
difference was observed at 20exion. Moreover,
increasing exion angle resulted in some differences in
contact pressure, predominantly in the partial and full
resection states. Contact pressure values in the intact,
torn, and repaired states were very similar between all
exion angles.
Review of the data found that they were normally
distributed. Measurable pressures were observed both
under the meniscus and between the femoral condyle
and tibial plateau, with maximum pressures observed
between the femoral condyle and tibial plateau in all
conditions. Results from the 6DoF load cell revealed no
differences in forces and torques in the anterior-
posterior and medial-lateral directions among groups
(intact, tear, repair, partial meniscectomy, and subtotal
meniscectomy) across all exion angles (Pvalues
greater than .05 for all cases) (Table 1).
Discussion
A large HCT in the medial meniscus decreased tibio-
femoral contact area, leading to increased contact
pressures when the knee was at or near full extension.
When the tear was repaired with a vertical suture
conguration, the contact area and pressure improved
and returned almost to baseline. With resection of the
superior leaet and subtotal meniscectomy, the contact
area was reduced and contact pressure increased pro-
portionally to the amount of meniscus removed.
This behavior was consistent throughout knee exion
(0,10
, and 20).
Historically, symptomatic HCTs have been treated
with the use of benign neglect or subtotal resection of
the inferior or superior lamina of the meniscus.
20
In
previous studies, the presence of a HCT has been
associated with joint degeneration.
15
Partial meniscec-
tomy has been performed to alleviate pain and prevent
the progression of tears.
20
Several attempts have been made to understand the
clinical impact of a horizontal tear and its treatment
with meniscectomy. Arno et al.
21
conrmed that
Table 1. Load and Torque Data From the 6-Degree of Freedom Load Cell for All Axes
Angle, Condition Fx, N Fy, N Fz, N Mx My Mz
0 Intact 53.73 104.89 1702.46 0.97 5.61 0.20
SD 43.86 47.61 189.35 7.18 4.13 0.68
0 Tear 50.22 102.80 1693.77 1.20 5.37 0.42
SD 50.62 31.16 193.63 5.10 5.18 0.61
0 Repair 47.72 105.64 1696.22 1.15 5.60 0.14
SD 56.37 47.75 186.21 8.26 7.07 0.74
0 Part res 50.26 102.90 1719.32 1.42 5.36 0.48
SD 55.28 44.58 190.70 7.65 6.40 0.52
0 Full res 67.28 104.88 1729.79 0.87 4.61 0.44
SD 63.63 41.86 191.23 7.49 7.94 0.73
10 Intact 213.08 204.14 1664.48 21.94 32.69 1.14
SD 58.28 43.99 190.84 5.90 5.58 1.49
10 Tear 219.20 212.74 1676.55 24.82 36.86 1.08
SD 47.50 45.08 188.10 7.78 5.25 1.26
10 Repair 190.37 212.69 1672.86 31.20 27.00 1.54
SD 44.51 56.01 178.37 9.99 7.59 1.33
10 Part res 191.63 202.32 1683.35 27.60 28.07 1.52
SD 49.64 54.90 185.29 8.96 7.49 1.36
10 Full res 210.35 208.12 1680.01 26.09 30.27 1.82
SD 66.40 52.19 180.09 8.38 7.90 1.32
20 Intact 350.06 298.44 1620.92 47.57 58.45 2.22
SD 52.30 51.86 148.91 5.66 7.75 1.82
20 Tear 370.73 303.64 1634.72 47.56 62.86 2.17
SD 59.26 60.46 153.96 8.54 8.98 1.99
20 Repair 343.26 301.31 1610.24 56.45 56.31 2.24
SD 45.50 69.02 163.22 8.09 8.93 1.96
20 Part res 331.37 289.63 1628.28 44.48 59.25 2.16
SD 56.69 71.65 153.81 9.75 8.75 2.06
20 Full res 367.04 303.52 1622.47 51.93 61.06 1.96
SD 55.24 59.98 155.04 7.20 7.56 2.15
NOTE. F denotes force in x, y and z axes (Fx, Fy, and Fz), while M denotes moment in x, y and z directions (Mx, My, and Mz).
res, resection; SD, standard deviation.
6B. S. BEAMER ET AL.
contact area decreases and contact pressure increases in
knees with a HCT during simulated walking, stair
climbing/descending, rising from a chair, and squatting.
They concluded that the presence of an untreated HCT
may lead to cartilage degradation. It is noteworthy that
the horizontal tears created in this study were longer
than those in the study of Arno et al.
21
Brown et al.
22
explored the difference in contact area and pressure
after partial meniscectomy and total resection for a
small horizontal tear during axial loading at full
extension. These authors created a tear near the pos-
terior horn of the medial meniscus and the resection
was of the inferior leaet rather than the superior
leaet resected in the present study. Their work, in
contrast to other published investigations and the pre-
sent study, suggested no signicant change in contact
area for any condition other than the total resection.
Although this study found no signicant detrimental
effects from removing the inferior leaet of HCTs, our
study found signicant increases in contact pressure
when the superior leaet was removed
22
Haemer et al.
4
tested small and large tears and found that both partial
meniscectomy and total resection of large tears caused a
signicant increase in contact pressure. None of these
investigations explored the effect of suturing the tear
together to simulate a repair.
HCTs of the meniscus can present a clinical dilemma
for orthopaedic surgeons. Leaving the tear alone may
result in tear progression, resulting in increased contact
pressures and degeneration of the articular cartilage
20
(Arno et al.,
21
Haemer et al.
4
). Alternatively, resection
of one leaet of the horizontal tear may be palliative
but result in a permanent loss of meniscal tissue. In
their study, Brown et al.
22
showed minimal detrimental
effects if the inferior leaet is resected. The present
study showed signicant changes in contact area and
contact pressure when the superior leaet was resected.
Both studies agree that resecting both leaets will lower
contact area and increase contact pressures, similar to a
subtotal resection. As a third option, the horizontal tear
could be repaired. If the tissue heals, a patients symp-
toms may resolve. By preserving their meniscus and its
function, further degeneration may be avoided by
restoring the contact area and contact pressure to near
normal.
At present, there are few studies describing the clin-
ical results after a repair of horizontal cleavage
meniscus tears. In recent systematic review, Kurzweil
et al.
16
found only 9 studies in the literature dating back
to 1980 that included at least one clinical outcome.
These studies included repairs of 98 HCTs and noted
success with freedom from reoperation in approxi-
mately 78%.
More recently, Pujol et al.
17
studied open repairs of
HCTs with and without the use of platelet-rich plasma.
At a mean follow-up of 34 months, only 3 of 34
patients did not respond (91% success). The study
noted no signicant differences in failure rate between
patients treated with and without platelet-rich plasma.
Likewise, Ahn et al.
18
followed 32 patients after a
symptomatic HCT repair. The tears were treated with
all-inside suture technique and marrow stimulation.
At an average of 45.6 months, only 3 repairs had
failed, resulting in a 91% success rate. Second-look
arthroscopy in 11 patients revealed 1 repair that had
failed to heal. Lastly, Salle de Chou et al.
23
studied
2 groups of patients receiving open repairs of HCTs.
One group of 18 patients was followed for more than
2 years, whereas the other group of 9 patients was
followed for more than10 years. Both groups showed
positive clinical results on their Lysholm and Interna-
tional Knee Documentation Committee scores as well
as decreased magnetic resonance imaging signal in
all patients. Most importantly, the positive results
achieved obtained in the short term were maintained
in the long term.
Limitations
As for limitations, this investigation was a controlled
laboratory experiment, not an in vivo clinical trial. As
such, it would be inappropriate to extrapolate our data
to clinical outcomes. The tears studied were large by
design and may not be applicable to smaller HCTs.
Moreover, an open repair technique was used in this
study because pressure sensor placement required a
wide dissection. All-inside arthroscopic techniques may
not produce the same results.
In this investigation, each specimen was subjected to
an axial load at varying degrees of knee exion. We did
not recreate the complex mixture of axial loading,
translation, rotation, and shear that is present in vivo.
Similarly, the effects of a torn, resected, or HCT on the
knees ligamentous stability was not investigated. The
coronary ligaments were resected partially to allow the
pressure lm to lie at on the tibial plateau. This partial
resection of this tissue may have increased the meniscal
motion. For comparison, the same methodology was
used in the controls and subsequent torn specimens. As
a relative change, our approach may or may not
recreate the natural state.
Each specimen was loaded for 20 cycles. They were
not tested to failure. As such, the durability of the repair
was not tested. Similarly, the impact of the suture on
the articular cartilage was not considered. Because the
NovoStitch device is relatively new, there is little clin-
ical experience with this repair technique. A recent
publication by Saliman
24
provides one perspective
regarding the feasibility of placing all-inside circumfer-
ential compression stitches to repair meniscus tears
in vivo.
HORIZONTAL TEARS AND JOINT CONTACT PRESSURE 7
Conclusions
The presence of a HCT in the medial meniscus causes
a signicant reduction in contact area and a signicant
elevation in contact pressure. These changes may
accelerate joint degeneration. A suture-based repair
of these HCTs returns the contact area and contact
pressure to nearly normal, whereas both partial and
subtotal meniscectomy lead to signicant reductions
in contact area and signicant elevations in contact
pressure within the knee. Repairing HCTs may lead to
improved clinical outcomes by preserving meniscal
tissue and the meniscal function.
Acknowledgment
The authors acknowledge Ceterix, Inc., for providing
repair devices used in this study and the staff at the
Scientic Instrumentation Facility at Boston Uni-
versitys Department of Physics for manufacturing the
biomechanical testing apparatus. The authors also
acknowledge Dr. Peter Kurzweil for providing
thoughtful feedback on the manuscript.
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8B. S. BEAMER ET AL.
... T he prevention and repair of meniscal injuries are very important for preventing early osteoarthritic changes. [1][2][3] Three groups of techniques have been developed for meniscal repair: outside-in, inside-out, and all-inside techniques. The all-inside technique has some benefits because it does not necessitate additional cuts for knot tying, 4 with the arthroscopic all-inside suture technique using meniscal repair devices involving preloaded sutures and nonabsorbable implants being the most popular technique. ...
Article
Full-text available
Horizontal and longitudinal tears are the most common injuries of the meniscus. The arthroscopic all-inside suture technique using meniscal repair devices involving preloaded sutures and nonabsorbable implants is the most popular technique. The 2 main disadvantages of this technique are the high cost and complications associated with implants. We have adopted some modern shoulder surgery techniques to repair horizontal and longitudinal meniscal tears. Our technique is based on the continuous lasso-loop margin convergence technique for rotator cuff repair (Lafosse’s continuous stitches). The technique is an implant-free, cost-effective procedure, which can be performed using general arthroscopic instruments.
... However, horizontal cleavage tears do have a higher correlation with altered biomechanics. In a 2017 cadaveric study, Beamer et al. reported a 70% increase in contact pressures across all flexion angles [72]. Furthermore, when managing this tear pattern with partial meniscectomy, prior studies have demonstrated that resection of one medial meniscal leaflet increased contact pressures by 33-46%, while resection of both leaflets increased pressure by 75-79% [73,74]. ...
Article
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Purpose of Review Anatomic repair of meniscal pathology is critical for restoring native joint biomechanics and kinematics for patients who suffer from meniscal tears. The purpose of this review was to summarize the pertinent anatomy, biomechanics, and kinematics of the meniscus to guide surgeons during meniscal repair procedures. Recent Findings Over the past decade, there has been a growing trend to save the meniscus whenever possible. The goal of repair should be to recreate native anatomy as close as possible to recapitulate normal mechanics. Studies describing the quantitative and qualitative relationship of the meniscus roots, ligaments, and attachments are key in guiding any meniscus repair. This review summarizes these relationships, with particular emphasis on meniscal roots and other key attachments to the meniscus. The composition, embryology, vascularization, biomechanics, in vivo kinetics, and in vivo kinematics of the meniscus are also discussed in this review. Summary Meniscal tears can cause profound functional, biomechanical, and kinematic derangements within the knee joint leading to accelerated degeneration of the articular cartilage. A strong understanding of the quantitative and qualitative relationships of the meniscus and its attachments with key arthroscopic landmarks will allow a surgeon to anatomically repair meniscal pathology in order to restore native joint biomechanics.
... Therefore, most injuries of the posterior horn of the medial meniscus occur on the basis of degenerative injuries. [14][15][16][17] The diagnosis depends on MRI examination and sports medicine examination to a large extent, and it is often missed in primary hospitals. Conservative treatment is always the first treatment. ...
Article
Objectives: To investigate the clinical efficacy of exposure enhancement technique and femoral condyle pushing technique applying in the posterior horn of the medial meniscus of the knee. Methods: From January 2016 to June 2019, 52 patients with injury in the medial meniscus treated in our department were selected. The horizontal tear of the posterior horn of the medial meniscus was repaired by exposure enhancement technique and femoral condyle pushing technique using the meniscus suture system. Postoperatively, the efficacy was evaluated using the Lysholm scoring system. Results: These 52 patients were all followed up for 3~18 months, with an average of 12.5 ± 7.3 months. The pain and activity of all patients were significantly improved compared with those before surgery. Conclusion: Exposure enhancement technique and femoral condyle pushing technique in the repair of the posterior horn of the medial meniscus presents satisfactory efficacy. It can improve the pain and activity of the knee, and enhance the stability of residual meniscus. Therefore, it is worth promoting.
... Recent evidence suggests that horizontal cleavage meniscal tears should also be repaired when able [14, 54•]. Beamer et al. compared contact area and pressure for intact menisci, menisci with horizontal cleavage tears, following meniscal repair with the Novostitch, after meniscectomy of a single leaflet, or after double leaflet meniscectomy [55]. The repair construct involves a single pass of suture through the peripheral part of the meniscus that is tied in a "haybale" fashion to reduce and compress the tear. ...
Article
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Purpose of Review The indications for partial meniscectomy are becoming increasingly limited, and recent evidence suggests that the meniscus should be preserved whenever possible. Because of its many proposed advantages, all-inside meniscus repairs are becoming increasingly common. This review discusses the indications, advantages, disadvantages, and biomechanical and clinical outcomes of all-inside meniscus repair. Recent Findings All-inside meniscus repair demonstrates equal functional outcomes, healing rates, and complications compared to inside-out repair of vertical longitudinal and bucket-handle tears with the advantages of decreased surgical time and faster post-operative recovery. In addition, return-to-sport and activity levels are high following all-inside repair regardless of whether concomitant anterior cruciate ligament reconstruction is performed. Biomechanical studies have demonstrated advantages of all-inside meniscal based repairs on radial and horizontal tears. Summary All-inside meniscus repair compares favorably to inside-out repair of vertical longitudinal and bucket-handle tears and continues to increase in popularity. Both capsular based and meniscal based repairs can be used to repair a variety of tear patterns. While biomechanical results are encouraging, further research on the clinical outcomes of meniscal based repairs is needed to elucidate the role of these techniques in the future.
... However, suturing is associated with a 15-30% risk of rerupture, 5 while resection is associated with a 14-fold higher risk of knee joint osteoarthritis (OA), 6 as it decreases the contact area and increases contact pressure between adjacent surfaces of the knee joint. 7 Meniscal allograft transplantation can address the limitations of meniscal suturing and excision. ...
Article
Full-text available
Partial meniscectomy, which is generally used for the treatment of meniscal tears, can lead to knee joint osteoarthritis. To prevent this important complication, attempting to restore normal knee joint kinematics and biomechanical forces after partial meniscectomy is essential. Implantation of a meniscal scaffold can be useful in this regard, improving the function of the meniscus on knee joint biomechanics after partial meniscectomy. Use of meniscal scaffolds would have specific clinical merit for young patients who are at highest for developing knee joint osteoarthritis over time. Herein, we describe our novel bioabsorbable meniscal scaffold, fabricated with polyglycolic acid coated with polylactic acid/caprolactone, used after partial meniscectomy for degenerative and irreparable meniscal tears. The method of implantation of the scaffold will have a determinant effect on clinical outcomes. As the implementation technique by arthroscopy will be influenced by the stiffness and strength of the scaffold implant used, we provide a detailed description of our implantation technique, including a description of the pitfalls to consider in order to improve clinical outcomes.
... Therefore, axial loading forces can no longer be adequately dissipated from the cartilage surface (Yim et al., 2013), leading to an increased risk for OA (Brown et al., 2016). These findings are supported by the results of Beamer et al., who indicated a moderate 8% increased peak CP after a horizontal cleavage tear repair when compared to the intact meniscal state (Beamer et al., 2017). The post-injured peak CP increase was approximately 70% after a horizontal cleavage tear. ...
Article
Full-text available
Purpose: Menisci transfer axial loads, while increasing the load-bearing tibiofemoral contact area and decreasing tibiofemoral contact pressure (CP). Numerous clinical and experimental studies agree that an increased CP is one predominant indicator for post-traumatic osteoarthritis (PTOA) of the knee joint. However, due to the immense variability in experimental test setups and wide range of treatment possibilities in meniscus surgery, it is difficult to objectively assess their impact on the CP determination, which is clearly crucial for knee joint health. Therefore, the aim of this systematic review is to investigate the influence of different meniscal injuries and their associated surgical treatments on the CP. Secondly, the influence of different test setups on CP measurements is assessed. On the basis of these results, we established the basis for recommendations for future investigations with the aim to determine CPs under different meniscal states. Methods: This review was conducted in accordance with the PRISMA guidelines. Studies were identified through a systematic literature search in Cochrane, PubMed and Web of Science databases. Literature was searched through pre-defined keywords and medical subject headings. Results: This review indicates a significant increase of up to 235% in peak CP when comparing healthy joints and intact menisci with impaired knee joints, injured or resected menisci. In addition, different test setups were indicated to have major influences on CP: The variety of test setups ranged from standard material testing machines, including customized setups via horizontal and vertical knee joint simulators, through to robotic systems. Differences in applied axial knee joint loads ranged from 0 N up to 2,700 N and resulted unsurprisingly in significantly different peak CPs of between 0.1 and 12.06 MPa. Conclusion: It was shown that untreated traumatic meniscal tears result in an increased CP. Surgical repair intervention were able to restore the CP comparable to the healthy, native condition. Test setup differences and particularly axial joint loading variability also led to major CP differences. In conclusion, when focusing on CP measurements in the knee joint, transparent and traceable in vitro testing conditions are essential to allow researchers to make a direct comparison between future biomechanical investigations.
... For example, while incomplete (<90% width) radial longitudinal tears show maintenance of load transfer, 9,50 large horizontal tears result in increased tibial contact pressure compared with uninjured controls. 8 Even tears that are small in size initially may propagate with time, resulting in larger and more complex tears or complete maceration of the tissue, with subsequent pain and dysfunction. ...
Article
Full-text available
Background The corrective procedures for meniscal injury are dependent on tear type, severity, and location. Vertical longitudinal tears are common in young and active individuals, but their natural progression and impact on osteoarthritis (OA) development are not known. Root tears are challenging and they often indicate poor outcomes, although the timing and mechanisms of initiation of joint dysfunction are poorly understood, particularly in large-animal and human models. Purpose/Hypothesis In this study, vertical longitudinal and root tears were made in a large-animal model to determine the progression of joint-wide dysfunction. We hypothesized that OA onset and progression would depend on the extent of injury-based load disruption in the tissue, such that root tears would cause earlier and more severe changes to the joint. Study Design Controlled laboratory study. Methods Sham surgeries and procedures to create either vertical longitudinal or root tears were performed in juvenile Yucatan mini pigs through randomized and bilateral arthroscopic procedures. Animals were sacrificed at 1, 3, or 6 months after injury and assessed at the joint and tissue level for evidence of OA. Functional measures of joint load transfer, cartilage indentation mechanics, and meniscal tensile properties were performed, as well as histological evaluation of the cartilage, meniscus, and synovium. Results Outcomes suggested a progressive and sustained degeneration of the knee joint and meniscus after root tear, as evidenced by histological analysis of the cartilage and meniscus. This occurred in spite of spontaneous reattachment of the root, suggesting that this reattachment did not fully restore the function of the native attachment. In contrast, the vertical longitudinal tear did not cause significant changes to the joint, with only mild differences compared with sham surgery at the 6-month time point. Conclusion Given that the root tear, which severs circumferential connectivity and load transfer, caused more intense OA compared with the circumferentially stable vertical longitudinal tear, our findings suggest that without timely and mechanically competent fixation, root tears may cause irreversible joint damage. Clinical Relevance More generally, this new model can serve as a test bed for experimental surgical, scaffold-based, and small molecule–driven interventions after injury to prevent OA progression.
... Later on, in the 1990s, clinicians discovered that total meniscectomy led to osteoarthritis within 5-10 years [20]. Several studies on cadavers from meniscectomies have observed increased contact pressures of up to 80-90%, which increases with progressively larger amounts of resection, and the augmented pressures experienced by articular cartilage can lead to premature cartilage wear [21,22]. In the knee, after a complete meniscectomy, the contact area is reduced by approximately 50%, resulting in a dramatic increase in load per unit area. ...
Article
Full-text available
Menisci are crucial structures for knee homeostasis. After a meniscal lesion, the golden rule, now, is to save as much meniscus as possible; only the meniscus tissue that is identified as unrepairable should be excised, and meniscal sutures find more and more indications. Several different methods have been proposed to improve meniscal healing. They include very basic techniques, such as needling, abrasion, trephination and gluing, or more complex methods, such as synovial flaps, meniscal wrapping or the application of fibrin clots. Basic research of meniscal substitutes has also become very active in the last decades. The aim of this literature review is to analyze possible therapeutic and surgical options that go beyond traditional meniscal surgery: from scaffolds, which are made of different kind of polymers, such as natural, synthetic or hydrogel components, to new technologies, such as 3-D printing construct or hybrid biomaterials made of scaffolds and specific cells. These recent advances show that there is great interest in the development of new materials for meniscal reconstruction and that, with the development of new biomaterials, there will be the possibility of better management of meniscal injuries
Article
This study investigated the immediate biomechanical effects of a biter-width partial medial meniscectomy. Small tears on the free edge of the meniscus are occasionally discovered during arthroscopic knee procedures. Removal of these tears often requires no more width than that of a biter from the edge. While past cadaveric partial meniscectomy studies have reported on the effects of meniscectomies from resection of one-third to three-quarters of meniscal width, the biomechanical sequelae of substantially smaller meniscectomies remain unknown. This study was performed to determine how single-biter-width meniscectomies affect the pressure distribution and peak pressure on the tibial plateau, as these parameters are correlated with increased likelihood of development of osteoarthritis. Eight cadaveric knees were instrumented with a thin-film pressure sensor underneath the menisci while retaining the major ligaments and most of the capsule. Knees were loaded to 1000 N at angles of flexion of 0, 15, 30, and 45 in normal tibio-femoral angles and in 7° of varus. Pressure, peak pressure, force and contact area were recorded. Afterwards, biter-width meniscectomies were performed, and measures repeated. There were significant changes in contact area at most flexion and tibio-femoral angles. There were no changes in the amount of force that was transmitted through the medial compartment. The overall pressure on the tibial plateau did not change in most knee conditions and peak pressure did not change significantly in any condition. The changes in contact area were consistent with our expectations. Similarly, the lack of change in force was also expected. However, the lack of significant changes in pressure and peak pressure represent findings indicating that a biter sized meniscectomy may have clinically insignificant effects on biomechanics.
Article
A basic understanding of meniscal anatomy and biomechanics is important for physicians evaluating knee injuries and surgeons treating meniscal injuries. This chapter provides a concise review of meniscal anatomy and biomechanics relevant for the evaluation and treatment of meniscus injuries. Anatomic landmarks relevant for meniscal root repair and transplant are discussed, along with the gross, microscopic, vascular, and neuroanatomy of the menisci.
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Purpose Many studies have demonstrated that injection of various growth factors including platelet-derived growth factor could increase meniscal cell activity and stimulate repair. The purpose of this study was to augment repair and promote meniscal healing by the use of platelet-rich plasma (PRP) within horizontal cleavage meniscal tears repaired via an open approach. The hypothesis was that the clinical outcomes and healing process would be improved using this meniscal healing augmentation technique. Methods In this case–control study, 34 consecutive young patients underwent an open meniscal repair to treat symptomatic Grade 2 or Grade 3 horizontal meniscal tears [median age 28 years (13–40)]. The median time between the onset of symptoms and surgery was 11.5 months (6–50). In the first group (17 consecutive patients, Group 1), a standard open meniscal repair was performed. In the second group (17 consecutive patients, Group 2), the same surgical repair was performed, but platelet-rich plasma was introduced into the lesion at the end of the procedure. Clinical outcomes were evaluated using KOOS and IKDC 2000 scores. MRI was performed at 1 year after surgery for objective evaluation. Results At a minimum of 24 months postoperatively (mean 32.2 months, 24–40), three patients underwent subsequent meniscectomy (two in Group 1, one in Group 2). The mean KOOS distribution (pain, symptoms, daily activities, sports, quality of life) was 78.4, 86.1, 93.8, 74.4, 74.6 in Group 1, and 93.3, 90.7, 97.1, 88.8, 78.3 in Group 2 (p
Article
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Complete radial tears near the medial meniscus posterior root attachment site disrupt the circumferential integrity of the meniscus (similar to a posterior root avulsion). These tears can compromise the circumferential integrity, and they have been reported in biomechanical studies to be comparable with the meniscectomized state. To quantify the tibiofemoral contact pressure and contact area changes that occur in cadaveric knees from complete posterior horn radial tears and subsequent repairs of the medial meniscus adjacent to the posterior root attachment site. Controlled laboratory study. Six nonpaired fresh-frozen human cadaveric knees each underwent 45 different testing conditions: 9 medial meniscus conditions (intact, root avulsion, root repair, serial radial tear at 3, 6, and 9 mm from the root attachment site, and in situ repair at the same 3 distances from the root attachment site) at 5 flexion angles (0°, 30°, 45°, 60°, and 90°), under a 1000-N axial load. Tekscan sensors were used to measure contact area and pressure in the medial and lateral compartments. The medial meniscus root avulsion and all radial tear conditions resulted in significantly decreased contact area and increased mean contact pressure compared with the intact state for knee flexion angles beyond 0° (P < .05). The root repair and in situ repairs restored contact area and pressure to levels statistically indistinguishable from those of the intact meniscus and increased contact area and decreased contact pressure compared with the corresponding tear conditions. Posterior horn radial tears adjacent to the medial meniscus root that extend to the meniscocapsular junction can lead to derangement of the loading profiles of the medial compartment that are similar to a root avulsion. Repair of these radial tears with an in situ pull-out technique restored joint mechanics to the intact state. Complete radial tears of the posterior horn of the medial meniscus, which occur relatively frequently, are biomechanically equivalent to root avulsions and could potentially lead to medial compartment arthrosis. An in situ repair offers an alternative treatment to meniscectomy and can reestablish the posterior anchor point, thus improving load distribution in the medial compartment. Future clinical studies of these repairs are recommended.
Article
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Over the past 30 years, many patients have benefited from arthroscopically assisted meniscus repair surgery and its ability to preserve a healthy knee. Although techniques have evolved, the basic premise of central-to-peripheral needle penetration across the tear with fixation into the capsular region immediately peripheral to the meniscus has remained. Suture repair techniques that involve encircling the tear have been discussed but have remained largely impractical because of the anatomic constraints of the arthroscopic knee. A suture-passing technology designed to function within these constraints was recently made available from Ceterix Orthopaedics (Menlo Park, CA). It allows surgeons to arthroscopically place circumferential sutures around meniscus tears to provide uniform, anatomic compression of the tear edges through an all-inside technique. This stitch is likely to improve healing rates and safety, as well as to enable repair of tears that were previously considered difficult or impossible to sew. The purposes of this note and accompanying video are to show the feasibility of placing all-inside circumferential compression stitches to treat tears of the knee meniscus and to discuss the potential benefits of such techniques.
Article
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Background: Meniscus deficiency may lead to degenerative arthritis in the knee. There is a significant emphasis on meniscus preservation, particularly in the young patient, to reduce the risk of arthritis. Purpose: To report on the incidence of meniscus repair and meniscectomy, with and without concomitant anterior cruciate ligament (ACL) reconstruction, in the United States (US) over the past 7 years. Study design: Descriptive epidemiology study. Methods: Patients who underwent arthroscopic meniscectomy (Current Procedural Terminology [CPT] codes 29880 and 29881), meniscus repair (CPT codes 29882 and 29883), and ACL reconstruction (CPT code 29888) for the years 2005 through 2011 were identified using the PearlDiver Patient Record Database. Age group and sex were collected for each patient. Patient groups included meniscectomy alone, meniscus repair alone, meniscus repair followed by meniscectomy, ACL reconstruction with concomitant meniscus repair, and ACL reconstruction with concomitant meniscus repair followed by meniscectomy. Linear regression and Student t tests were utilized for comparisons, with an α value of .05 set as significant. Results: The database represented approximately 9% of the US population under 65 years of age. There was no significant change in the number of patients in the covered population during the study time frame (P = .138). From 2005 to 2011, there were a total of 387,833 meniscectomies, 23,640 meniscus repairs, and 84,927 ACL reconstructions. There was a significant increase in the total number of isolated meniscus repairs performed (P = .001) and a doubling of the incidence of repairs from 2005 to 2011. There was no significant increase in the total number of meniscectomies performed (P = .712), while the incidence of meniscectomies increased only 14% from 2005 to 2011. There was no significant change in the number of meniscus repairs performed at the same time as ACL reconstruction during the study time frame. The total number and incidence of meniscectomies after repair with and without ACL reconstruction significantly decreased. Conclusion: There has been an increased number of isolated meniscus repairs being performed in the US over the past 7 years without a concomitant increase in meniscectomies over the same time frame. These data suggest that meniscus repairs are preferentially being performed over meniscectomies.
Article
Background: Horizontal, degenerative tears of the medial meniscus and subsequent meniscectomy can compromise the biomechanical function of the meniscus in load transmission and weightbearing, leading to the development of radiographic and symptomatic tibiofemoral arthritis. Hypothesis: Resection of both leaflets of a horizontal medial meniscal tear will increase peak contact pressures and decrease contact areas in comparison with resection of only the inferior leaflet. Study design: Controlled laboratory study. Methods: Twelve fresh-frozen human cadaveric knees had tibiofemoral peak contact pressures and contact areas under an 1800-N axial load measured by Tekscan in the control state. A horizontal tear was created in the posterior horn of the medial meniscus, and the knees were retested. The knees were tested a third time after resection of the inferior leaflet (single leaflet) and a final time after resection of the superior leaflet (both leaflets). The Friedman test was used to test for group differences in peak pressure (psi) and contact area (mm(2)) between test conditions (native, tear, inferior leaflet resection, and resection of both leaflets). Results: For the medial compartment, there was a statistically significant difference in peak pressure (P = .03) but not in contact area (P = .70) between testing conditions. Median peak pressure in the medial compartment was significantly greater for resection of both leaflets compared with the tear (406.5 vs 294.7 psi, respectively; P = .002). Median contact area in the medial compartment was greatest for resection of both leaflets (602.7 mm(2)), but there were no statistically significant differences between test conditions (P = .70). For the lateral compartment, there were no statistically significant differences in peak pressure (P = .99) or contact area (P = .77) between test conditions. Conclusion: Resection of a single inferior leaflet after a horizontal medial meniscal tear preserves much of the original biomechanical function of the meniscus. Resection of both leaflets leads to a significant increase in contact pressure dispersed over the same contact area, which results in an undesirable biomechanical environment. Clinical relevance: Arthroscopic inferior leaflet resection is a viable option for providing symptomatic relief of horizontal medial meniscal tears and preserves the ability of the meniscus to absorb axial loading on the knee joint, theoretically decreasing the risk of subsequent osteoarthritis.
Article
Introduction: Symptomatic horizontal meniscal tears are rare but worrisome lesions in young adults. These are overuse injuries not amenable to the classic arthroscopic sutures. An open meniscal repair allows the meniscal lesion to be suture vertically, perpendicular to its in the vascularized zone. The purpose of this study was to evaluate the short and long-term clinical and radiological outcomes of the aforementioned surgical technique. Material and method: The first cohort consisted of 24 patients operated between 2009 and 2011 (6 women, 18 men; mean age 26years) having 11 lateral and 13 medial meniscal tears. The second cohort was of 10 patients operated between 2001 and 2002 (3 women, 7 men; mean age 24years) having 8 lateral and 2 medial meniscal tears. Patients were reviewed at the last follow-up using the IKDC, Lysholm and KOOS scores. Patients in the first cohort had an MRI, while those in the second cohort had X-rays. Results: Eighteen patients in the first cohort were reviewed with a mean follow-up of 2years (12-45months) and 9 patients from the second cohort were reviewed after 10years (97-142months). In the first cohort, one patient required secondary menisectomy. The mean Lysholm score was 90 and the subjective IKDC was 85. Every MRI examination found reduced extent and intensity of the hyperintense signal. In the second cohort, no patients required secondary meniscectomy. Two patients had joint space narrowing (less than 50%) on radiographs. The mean Lysholm score was 99 and the subjective IKDC was 91. Conclusion: Open repair of horizontal meniscal tears in young adults leads to good subjective and objective results in the short term, which are maintained in the long-term. Level of evidence: Level IV - retrospective study.
Article
To test contact pressures in the knee after treatment of a radial meniscus tear with an all-inside meniscal repair technique and compare the results with inside-out repair and partial meniscectomy. Six non-paired cadaveric knees were analyzed with intra-compartment pressures measured at loads of 250N, 500N and 1000N at 0°, eight degrees, 15°, and 30° of knee flexion. Compartmental contact pressures were measured for the intact medial meniscus, radial tear in the posterior horn, all-inside repair using the NovoStitch suture passer device (Ceterix Orthopaedics Inc., Menlo Park, CA), inside-out repair method, and partial meniscectomy. One-way ANOVA was used for statistical analysis. The greatest differences in peak pressures between treatments were observed under 1000N load at 30° flexion (0.8±(SD)0.1MPa (intact meniscus), 0.8±(SD)0.1MPa (all-inside), 0.9±(SD)0.1MPa (inside-out) and 1.6±(SD)0.2MPa (partial meniscectomy)). Treatment with partial meniscectomy resulted in the highest peak pressures compared to all other states (p<0.0001 at each angle). Repair of the radial tear using the all-inside technique as well as the inside-out technique resulted in significantly decreased compartment pressures compared to partial meniscectomies (p<0.0001 at each angle). There were no significant differences between peak pressures in the intact state and after repair with the all-inside or inside-out techniques. An all-inside repair technique using the NovoStitch suture passer can decrease contact pressures for a radial meniscus tear similarly to the inside-out repair technique when compared to partial meniscectomy. This novel arthroscopic suture passer warrants further analysis in the clinical setting as it may be a reliable method for repair of radial meniscal tears through an arthroscopic all-inside technique. Copyright © 2015 Elsevier B.V. All rights reserved.
Article
The purpose of this study was to determine if a horizontal cleavage lesion (HCL) of the posterior horn of the medial meniscus would result in changes to tibiofemoral contact mechanics, as measured by peak contact pressure and contact area, which can lead to cartilage degeneration. To study this, 10 cadaveric knees were tested in a rig where forces were applied (500 N Compression, 100 N shear, 2.5 Nm Torque) and the knee dynamically flexed from −5° to 135°, as peak contact pressure and contact area were recorded. After testing of the intact knee, a horizontal cleavage lesion was created arthroscopically and testing repeated. The Wilcoxon signed-rank test was used to determine if there were differences in peak contact pressure and contact area between the intact knee and that with the HCL. A statistically significant increase in peak contact pressure of 13%, on average, and a decrease in contact area of 6%, on average, was noted following the HCL. This suggests that a horizontal cleavage lesion will result in small but statistically significant changes in tibiofemoral contact mechanics which may lead to cartilage degeneration. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Article
Purpose: The purpose of this study was to evaluate patients after arthroscopic repair of meniscal horizontal tears with a marrow-stimulating technique through clinical signs and second-look arthroscopy. Methods: We retrospectively reviewed a consecutive series of 32 meniscal repairs with horizontal cleavage tears and evaluated them through clinical assessment and second-look arthroscopic examinations. Arthroscopic meniscal repair and a marrow-stimulating technique were performed. Functional outcomes were evaluated using the visual analog scale (VAS) pain score, Lysholm knee scoring scale, and Tegner activity scale. Assessment of meniscal healing was evaluated clinically by the presence of meniscal signs; second-look arthroscopy was performed in 11 patients. Correlation between chronicity of a meniscal lesion (time from initial symptom [TFIS]) and meniscal healing was evaluated. Results: The mean follow-up period was 45.6 +/- 13.9 months. Improvements in mean VAS scores from 6.7 to 1.9 (P < .001) were observed. The Lysholm score increased from 48.0 +/- 14.4 to 92.0 +/- 6.3 (P < .001). The Tegner activity score increased from 3.3 +/- 1.1 to 6.8 +/- 0.8 (P < .001). At the last follow-up, 29 of 32 patients (91%) were evaluated as healing in the clinical assessment. Of the 11 patients who underwent second-look arthroscopy, 8 (73%) showed complete healing, 2 (18%) had incomplete healing, and 1 (9%) failed to heal. Correlation between TFIS and meniscal healing was clinically significant (P = .001) but arthroscopically insignificant (P = .085) on second-look arthroscopy. Conclusions: The meniscal repair procedure for horizontal cleavage tears in the present study suggests an alternative treatment option to approach the treatment of meniscal tears extending into the avascular zone and degenerative tissue. The marrow-stimulating technique using a cannulated reamer can be considered as an alternative method for the augmentation of meniscal healing.
Article
Purpose Despite the well-documented advantages of meniscal repair over meniscectomy, horizontal cleavage tears (HCTs) are often not repaired. Reported reasons include difficulty performing the repair, potential suture failure due to mechanical stresses, and poor healing rates. In addition, many surgeons have the perception that debriding the tear until the superior and inferior laminae are stable results in a good clinical outcome. Furthermore, many of the tears occur in patients who are older than the generally accepted indicated age for repair and may also have a degenerative component, making them potentially less likely to benefit from repair. This review was performed to evaluate the published outcomes of HCT repairs and test the hypothesis that surgically repaired HCTs have an unacceptably low rate of success. Methods A systematic search of the PubMed and Embase databases was performed in December 2013 to identify studies in which meniscal HCTs were repaired. Inclusion criteria for the analysis were English language, reference to a patient with an HCT repaired by any method, and a report of at least 1 postoperative outcome. For the purposes of this review, a failed outcome was defined as the need for reoperation. Results More than 16,000 abstracts were returned in the search. From these abstracts, we identified 210 articles for further review, of which 9 met the inclusion criteria. A total of 98 repairs of horizontal tears were evaluated in these studies. By use of reoperation as the criterion for treatment failure, 77 of the repairs were successful, for an overall success rate of 77.8%. Conclusions The literature does not support the hypothesis that surgically repaired HCTs have an unacceptably low rate of success. Rather, our results show that existing studies of repaired HCTs show a comparable success rate to repairs of other types of meniscal tears. Level of Evidence Level IV, systematic review of Level IV studies.