High tibial osteotomies are a surgical procedure used to treat unicompartmental osteoarthritis of the knee caused by malalignment. There are several types of high tibial osteotomies including medial opening wedge, lateral closing wedge, medial opening hemicallotasis, and dome osteotomies. Complications can include recurrence of deformity, irritation or failure of implants, nerve palsy, nonunion, infection, or stiffness. Outcomes of high tibial osteotomies are generally good, though some patients may eventually require total knee arthroplasty. High tibial osteotomies can be combined with cartilage restoration procedures, though long-term outcomes of graft survival are mixed.
2. Introduction
ā¢ The complex etiology of knee osteoarthritis includes overuse,genetic
factors, prior knee trauma, chronic ligamentous instability, cartilage and
meniscal defects, obesity, and biomechanical derangements such as
anatomic malalignment.
ā¢ The most deļ¬nitive surgical option for the symptomatic, aging patient with
arthritis remains total knee arthroplasty In younger patients with
unicompartmental chondral injuries secondary to lower-extremity
malalignment,
ā¢ High tibial osteotomy is a well-established procedure for the treatment of
unicompartmental osteoarthritis of the knee.
ā¢ Most reports have shown approximately 80% satisfactory results at 5 years
and 60% at 10 years after high tibial osteotomy.
3. Biomechanics
ā¢ The knee is a pivotal weight-bearing hinge joint characterized
primarily by ļ¬exion and extension movements with slight internal and
external rotation.
ā¢ Joint reactive forces across the knee may be up to six times body
weight when climbing stairs
ā¢ The weight-bearing load distribution in the normal knee is 60% to
75% in the medial compartment.
ā¢ The most common deformity in patients with osteoarthritis of the
knee is a varus position.
4.
5. High Tibial Osteotomies
ā¢ Basically presented with 4 types:
1. Medial opening wedge.
2. Lateral closing wedge.
3. Medial opening Hemicallotasis.
4. Dome.
ā¢ A recent meta analysis however revealed no significant differences in union
rate between closing and opening-wedge HTOs.
Smith TO, Sexton D, Mitchell P, Hing CB. Opening- or closing-wedged high tibial osteotomy: a meta-analysis of clinical and radiological outcomes. Knee.
2011 Dec;18(6):361-8. Epub 2010 Oct 29
6. Indications
ā¢ Symptomatic osteoarthritis.
ā¢ Medial compartment of the varus knee.
ā¢ Active patient.
ā¢ Additional indications for this procedure include unloading a cartilage
restoration site after a cartilage preservation procedure or changing the
sagittal slope to address cruciate ligament insufļ¬ciency with or without a
concomitant ligament reconstruction
7. Contraindications
ā¢ Narrowing of lateral compartment cartilage space.
ā¢ Lateral tibial subluxation of more than 1 cm.
ā¢ Medial compartment tibial bone loss of more than 2 or 3 mm.
ā¢ Flexion contracture of more than 15 degrees.
ā¢ knee flexion of less than 90 degrees.
ā¢ More than 20 degrees of correction needed.
ā¢ Inflammatory arthritis.
ā¢ Significant peripheral vascular disease
8. Preoperative Planning.
ā¢ Full Length X-ray from the hip to ankle.
ā¢ We measure the Mechanical axis.
ā¢ Overcorrection of 3-5 degree is recommended.
ā¢ The correction angle is generally proportional to
the osteotomy distraction at the level of the medial
cortex in roughly a 1-to-1-mm relationship
9. LATERAL CLOSING WEDGE OSTEOTOMY
ā¢ Coventry described a closing wedge osteotomy made proximal to the tibial
tuberosity.
ā¢ He recommended a lateral approach to correct a varus deformity and a
medial approach to correct a valgus deformity.
ā¢ The advantages of this osteotomy are .
1. it is made near the deformity, that is, the knee joint.
2. it is made through cancellous bone, which heals rapidly.
3. it permits the fragments to be held firmly in position by staples or a rigid fixation
device, such as a plate-and-screw construct.
4. it permits exploration of the knee through the same incision
ā¢ Due to Recurrence of pain he recommended the overcorrection up to 8
degree.
10.
11.
12. MEDIAL OPENING WEDGE OSTEOTOMY
ā¢ Hernigou et al. described a medial opening wedge tibial osteotomy.
ā¢ They believed is more precise and allows more exact correction than
does a lateral closing wedge osteotomy.
ā¢ It is preferable when the involved extremity is 2 cm or more shorter
than the contralateral extremity or laxity of the medial collateral
ligament or combined anterior cruciate ligament deficiency.
ā¢ It is critical to identify the superļ¬cial medial collateral ligament
(sMCL) and elevate its entire insertion on the medial aspect of the
tibia
14. OPENING WEDGE HEMICALLOTASIS
ā¢ Schwartsman advocated the use of circular external fixation after
percutaneous tibial osteotomy (Ilizarov technique).
ā¢ He suggested that:
ā¢ Healing is better.
ā¢ Placement of the osteotomy below the tibial tubercle minimizes the chance
of patella infera and
ā¢ Loss of proximal tibial bone stock that may complicate later TKA.
ā¢ Disadvantage:
ā¢ Poor Patient acceptance.
ā¢ Risk of Pin loosening and Infection.
ā¢ Close follow up reuired.
15.
16.
17. Dome Osteotomy
ā¢ Maquet described a ābarrel vault,ā or dome, osteotomy, which he
believed allowed more accuracy and adjustability of correction.
ā¢ It may be considered if a correction angle of >20 is desired.
ā¢ An osteotomy cut in the shape of an inverted U is made above the
level of the tibial tubercle
ā¢ Stable , no need for fixations but pins or External fixation can be used
if necessary.
ā¢ Disadvantages
1. technical difficulty,
2. Intraarticular fracture.
3. scarring around the patellofemoral extensor mechanism.
18. Complications
ļ¼Reported complication rates for HTO are 7% to 55%
ā¢ Recurrence of deformity (loss of correction) in 5% to 30%
ā¢ Irritation to implant & Implant Failure.
ā¢ Peroneal nerve palsy.
ā¢ Nonunion
ā¢ Infection.
ā¢ knee stiffness or instability,
ā¢ Intraarticular fracture.
ā¢ DVT.
ā¢ Compartment syndrome.
ā¢ Patella baja.
ā¢ Osteonecrosis of the proximal fragment
19. HTO Versus Unicompartmental Knee Arthroplasty (UKA)
ā¢ The outcomes of HTO and UKA are similar.
Dettoni F, Bonasia DE, Castoldi F, Bruzzone M, Blonna D, Rossi R. High tibial osteotomy versus unicompartmental knee
arthroplasty for medial compartment arthrosis of the knee: a review of the literature. Iowa Orthop J. 2010;30:131-40.
ā¢ A meta-analysis by Spahn et al. found that after a nine to
twelve-year follow-up, survivorship of HTO was 84.4% and
UKA was 86.9%, with comparable clinical results and no
difference in the complication rates.
Spahn G, Hofmann GO, von Engelhardt LV, Li M, Neubauer H, Klinger HM. The impact of a high tibial valgus osteotomy and
unicondylar medial arthroplasty on the treatment for knee osteoarthritis: a meta-analysis. Knee Surg Sports Traumatol
Arthrosc. 2013 Jan;21(1):96-112. Epub 2011 Nov 11.
20. TKA After HTO
ā¢ At 10 to 15 years after proximal tibial osteotomy, 40% of patients require conversion to
total knee arthroplasty
ā¢ Both opening and closing-wedge osteotomies change anatomic relationships within the
knee, potentially complicating subsequent TKA.
ā¢ Historically, lateral closing-wedge HTOs created problems with everting the patella,
balancing ligaments, and removing retained implants. In addition, the increased risk of
patella baja.
ā¢ A study by van Raaij et al. showed increased operative time, an increased number of
combined procedures, and less postoperative knee motion for patients undergoing TKA
after HTO.
ā¢ Erak et al. compared a group of thirty-six TKAs performed after opening-wedge HTO with
a group of 1315 primary TKAs and found that patients in whom the TKA followed
opening-wedge HTO had a poorer knee score and greater pain.
Erak S, Naudie D, MacDonald SJ, McCalden RW, Rorabeck CH, Bourne RB. Total knee arthroplasty following medial opening wedge tibial osteotomy: technical issues
early clinical radiological results. Knee. 2011 Dec;18(6):499-504. Epub 2010 Dec 8.
21. HTO and Concomitant Cartilage Procedures
ā¢ Bauer et al. evaluated eighteen patients who underwent HTO
combined with matrix-induced autologous chondrocyte implantation
(MACI) and reported clinical improvement at ļ¬ve years. However,
magnetic resonance imaging demonstrated poor graft survival and
cartilage inļ¬ll.
Bauer S, Khan RJ, Ebert JR, Robertson WB, Breidahl W, Ackland TR, Wood DJ. Knee joint preservation with combined neutralising high tibial osteotomy (HTO) and
matrix-induced autologous chondrocyte implantation (MACI) in younger patients with medial knee osteoarthritis: a case series with prospective clinical and MRI
follow-up over 5 years. Knee. 2012 Aug;19(4):431-9. Epub 2011 Jul 22.
ā¢ Wong etal. showed good short-term clinical outcomes after HTO
performed in combination with intra-articular injection of
mesenchymal stem cells.
Wong KL, Lee KB, Tai BC, Law P, Lee EH, Hui JH. Injectable cultured bone marrow-derived mesenchymal stem cells in varus knees with cartilage
defects undergoing high tibial osteotomy: a prospective, randomized controlled clinical trial with 2 yearsā follow-up. Arthroscopy. 2013
Dec;29(12):2020-8
22. ā¢ In a recent systematic review, Harris et al. analyzed HTO performed
with or without articular cartilage restoration surgery and/or allograft
meniscal transplantation. They found that HTO performed in
combination with other procedures led to excellent short-term and
intermediateterm survival and clinical outcomes; however, there was
a deterioration in outcomes at ten years.
Harris JD, McNeilan R, Siston RA, Flanigan DC. Survival and clinical outcome of isolated high tibial osteotomy and combined
biological knee reconstruction. Knee. 2013 Jun;20(3):154-61. Epub 2013 Mar 9.