Total knee arthroplasty coincident with high tibial osteotomy

Established lower limb alignment and knee stability are the two main prognosis factors influencing good functional result and prosthesis life. During Total Knee Arthroplasty (TKA), correction of tibial extra-articular deformity cannot be achieved without ligament balancing. Excessive valgus deformity after a failed high tibial osteotomy (HTO) necessitates a much larger resection of bone from the medial tibial plateau resulting in a trapezoidal extension gap. In overcorrected valgus knee patients after failed HTO, meticulous preoperative planning is required to predict complementary procedures needed to achieve flexion-extension balance with optimal postoperative lower limb alignment. This article details the preoperative planning involved and the intraoperative technique used in such cases. We describe a planning methodology consisting of measuring medial and lateral distance between future femoral and tibial orthogonal resection lines, drawn on valgus and varus stress radiographs (arrows). If the medial distance (medial arrows) on the valgus stress radiographs is longer than the lateral arrows on the varus stress radiographs, a lateral release will be necessary to achieve a rectangular extension gap during TKA procedure. However, the lateral release needed to compensate medial bone resection is limited. This limit must not exceed 10 millimeters (about 8 to 10° of valgus malunion). Over this limit, total knee arthroplasty plus corrective tibial osteotomy is one of the solutions. We prefer to insert prosthesis inside the “ligament box”; without any ligamentous release. The limb alignment is achieved with corrective tibial osteotomy. We propose and describe how to carry out TKA based on a rectangular extension gap, associated, in the same procedure, with a HTO to restore a neutral alignment of the leg.     

Lateral femoral sliding osteotomy in total knee arthroplasty for fixed valgus deformity

We treated 13 patients who had a fixed valgus deformity of the knee with a semi-constrained total knee arthroplasty combined with advancement of the lateral collateral ligament by means of a lateral femoral condylar sliding osteotomy. At follow-up of between 1 and 6.5 years, all patients were assessed using the Knee Society score. The mean knee score improved from 32 to 88 and the functional score from 45 to 73. The mean tibiofemoral angle was corrected from 191 to 180°. There was no postoperative tibiofemoral or patellar instability and, in most knees, distal transposition of the lateral femoral condyle achieved satisfactory stable alignment.     

Multiple needle puncturing: balancing the varus knee

The so-called "pie crusting" technique using multiple stab incisions is a well-established procedure for correcting tightness of the iliotibial band in the valgus knee. It is, however, not applicable for balancing the medial side in varus knees because of the risk for iatrogenic transsection of the medial collateral ligament (MCL). This article presents our experience with a safer alternative and minimally invasive technique for medial soft tissue balancing, where we make multiple punctures in the MCL using a 19-gauge needle to progressively stretch the MCL until a correct ligament balance is achieved. Our technique requires minimal to no additional soft tissue dissection and can even be performed percutaneously when necessary. This technique, therefore, does not impact the length of the skin or soft tissue incisions. We analyzed 61 cases with varus deformity that were intraoperatively treated using this technique. In 4 other cases, the technique was used as a percutaneous procedure to correct postoperative medial tightness that caused persistent pain on the medial side. The procedure was considered successful when a 2- to 4-mm mediolateral joint line opening was obtained in extension and 2 to 6 mm in flexion. In 62 cases (95%), a progressive correction of medial tightness was achieved according to the above-described criteria. Three cases were overreleased and required compensatory release of the lateral structures and use of a thicker insert. Based on these results, we consider needle puncturing an effective and safe technique for progressive correction of MCL tightness during minimally invasive total knee arthroplasty.     

Total knee replacement in severe genu varum deformity

In patients with osteoarthritis (OA) and severe osseous deformity of the knee, total knee replacement (TKR) is a major challenge. If the preoperative deformity exceeds 15°, restoration of the correct mechanical alignment will be difficult to achieve. In the management of medial compartment OA associated with a deformity of more than 15°, there is no agreement on the policy to adopt. The first step to be taken is a detailed analysis of the deformity, to determine where it is articular (wear, laxity) or extra-articular (constitutional or acquired bony deformity). The options open to the surgeon are: isolated valgus osteotomy (with TKR at a later stage), TKR or one-stage opening-wedge tibial valgus osteotomy and TKR. This chapter examines the different options and describes the authors’ preferred strategy.     

Quadriceps dislocation medial approach for intraarticular and medial structures of the knee

To minimize possible complications such as patellar subluxation, quadriceps atrophy and skin tightness and slough which interfere with successful rehabilitation following knee surgery, the author employed a quadriceps dislocation medial approach for total knee arthroplasty and ligament (medial and both cruciates) surgery. The results of this approach (99 knees) were compared with a medial capsular incision approach (111 knees), a lateral capsular incision approach (114 knees), and Hughston's medial hockey stick incision approach (122 knees). The skin slough, patellar subluxation, and sense of tightness during rehabilitation occurred least with the quadriceps dislocation medial approach (P less than .05). The quadriceps dislocation medial approach was also the most convenient approach of the four.     

Current concepts on management of medial and posteromedial knee injuries

Traditionally, while managing ligament injuries around the knee, medial side injuries are frequently overlooked or considered ‘benign’ with very little influence on overall knee stability outcomes. However, much has changed in the recent past, and like the lateral side of the knee, it is gaining considerable attention. It is now well known that the Medial collateral ligament and Posteromedial corner are fundamentally two distinct structures that differ in anatomy and biomechanics. When it comes to decision making between conservative versus operative approach for medial side injuries, treating orthopaedic surgeons are subjected to walking on a thin line trying to balance between potential residual laxity and joint stiffness. This review will delve into some of the recent works focusing on the medial side injuries and discuss the evolving concepts.     

侧方应力摄片测量和膝关节MRI诊断内侧副韧带损伤的临床研究

目的:研究双膝外翻应力位摄片对膝关节内侧副韧带损伤的诊断意义。方法:自2008年1月至2011年6月收治膝关节内侧副韧带损伤46例,31例行手术治疗,15例保守治疗,其中1例保守治疗3个月无效后手术。其中男32例,女14例;年龄28～72岁,平均(49.46±22.54)岁;左膝22例,右膝24例。常规行损伤侧、正常侧的应力位下和非应力位下X线摄片和MRI检查,对于内侧间隙明显增宽和MRI表现有深层断裂及后交叉韧带损伤的择期行切开内侧副韧带行缝合或重建术。以胫骨平台内侧髁和外侧髁作一条连线记为A线,将此线向上平移至股骨内侧髁最内缘记为B线,然后测量这2条线的垂直距离记为C。间隙差比值(R)计算方法为(患侧应力下间隙-患侧无应力下间隙)/(健侧应力下间隙-健侧无应力下间隙)。总结R值区间与术中所见韧带损伤种类的关系。结果:46例中17例有韧带浅层撕裂,21例深层断裂,8例合并有后关节囊或后交叉韧带断裂,当比值介于1.51～5.24时,内侧副韧带损伤表现为浅层撕裂的有15例,实际损伤为17例,诊断正确率为88.24%;当比值介于5.28～13.85时,表现为深层断裂的有19例,实际损伤为21例,诊断正确率为90.48%;当比值介于15.61～26.25时,表现为合并后关节囊或交叉韧带断裂的有7例,实际损伤为8例,诊断正确率为87.50%。结论:以膝关节受伤侧关节间隙差值与正常侧差值的比值作为衡量标准,可以提供膝关节内侧副韧带损伤的量化分级。     

Complex instability of the anterior knee

Complex knee instability involves the anterior cruciate ligament (ACL) and one or more major stabilizers of the knee [medial collateral ligament (MCL), lateral collateral ligament (LCL), posterior cruciate ligament (PCL)]. The medial side has a high healing potential and does not need operative treatment in most cases if ACL reconstruction is performed. Reconstruction of the medial ligament complex is indicated in gross instability of the medial meniscus fixation, dislocation of the MCL into the joint, and large dislocated bony avulsions. Injuries on the lateral side do not heal spontaneously and require acute operative treatment (first 2 weeks). Frank knee dislocations and gross multiligament injuries should be reduced acutely, and the integrity of the vascular structures must be examined closely. In a European multicenter study, operative treatment with reconstruction of both cruciate ligaments and functional rehabilitation gave better results than conservative treatment with immobilization of the joint.     

Lateral approach is advantageous in total knee arthroplasty for valgus deformed knee

Introduction

For the total knee arthroplasty in valgus deformed knee, superiority of the medial or lateral approach is still controversial. We compared the short-term result of two approach groups.

Materials and methods

Forty-seven knees in rheumatoid arthritis with valgus deformity from 6° to 24° were randomly divided into two group; medial approach (24 knees) and lateral approach (24 knees). We used Scorpio NRG PS for all knees. Median postoperative periods were 43 months in both groups. We compared the surgical time, and alignment on standing radiograph, range of motion (ROM) pre/postoperatively, and degrees of soft-tissue release procedure, and lateral laxity measured by stress radiograph immediately after operation and at final follow-up.

Result

Pre/postoperative alignment, surgical time, lateral laxity, and preoperative ROM had no significant in two groups; however, postoperative flexion was superior in lateral approach group 123.8°, 109° in medial approach group. All cases required iliotibial band (ITB) release at Gerdy’s tubercle, 83 % ITB at joint level, 21 % lateral collateral ligament (LCL), 17 % popliteus tendon (PT) in medial approach group, and 88 % ITB at Gerdy’s tubercle, 46 % ITB at joint level, 13 % LCL, 4 % PT in lateral approach group.

Discussion

In the valgus knee, lateral structures are tight. Lateral approach can directly adjust the tight structure, and also less vascular compromise to the patella than medial approach with lateral patellar release. Less invasiveness to the quadriceps muscle in lateral approach could result into better range of motion after the surgery.     

Total knee replacement in the fixed valgus deformity using a lateral approach: role of the automatic iliotibial band release for a successful balancing

The purpose of this work was to document eleven years of experience in knee replacement for fixed knee valgus through a lateral approach with special emphasis on the balancing procedures. At a mean follow-up of seven years, only one revision for sepsis was required in this series of 63 knee replacements. The mean knee score improved from 37 (range 20–45) to 91 (range 65–100) at the last review (p < 0.01) while the function score increased from 29.5 (range 0–50) to 78.7 (range 10–100) (p = 0.01). The mean mechanical axis (HKA) was 14.7° of valgus preoperatively and 1° of valgus postoperatively. After the iliotibial band was automatically released in the approach, only four of 63 knees required additional release for tightness in extension. These results underline the appeal of the lateral approach with the automatic release of the iliotibial band. If required, additional ligament release is recommended step-by-step after bone section to avoid postoperative instability.     

Bone resection and ligament treatment for flexion contracture in knee arthroplasty

A retrospective study of 103 knees (88 patients) who had primary total knee arthroplasty with a flexion contracture ranging from 20 degrees to 60 degrees was done to tabulate the primary soft tissue structures released during surgery and to identify any residual deformity. The average flexion contracture preoperatively was 27.1 degrees +/- 8 degrees and postoperatively was 2.7 degrees +/- 3.4 degrees (range, 0 degrees -10 degrees ). The average followup was 70.4 months (range, 12-180 months). Only medial or lateral soft tissue balancing procedures were necessary to correct the flexion contracture in 37 knees (35.9%) and no medial or lateral release was necessary in 25 knees (24.3%), of which 16 had a balanced posterior cruciate ligament. The posterior capsule was released on the deformity side of the knee in 15 knees (14.6%) and on the opposite side of the deformity in seven knees (6.8%). The posterior cruciate ligament was balanced in 21 knees (20.4%) and was released in four knees (3.9%). For all knees in which the posterior cruciate ligament was released or balanced, it was done for excessive rollback and tightness in flexion and not for flexion contracture management. In two patients (2%) an additional 4 mm of distal femur was resected for a 45 degrees and a 25 degrees flexion contracture. The data suggest that a contracted collateral ligament is the most likely primary structure whose effective release allows correction of the flexion contracture in most cases.     

Primary reconstruction of injuries of the capsular ligament of the knee joint

Whether operative or conservative treatment is indicated for acute knee ligament injuries depends on the lesions of the cruciate ligaments: complex instability with rupture of one or both cruciate ligaments and injuries to the lateral or medial ligamentous structures should be treated by operation. Surgical treatment of an isolated rupture of the anterior cruciate ligament is recommended only for the young active patient. Surgery is performed by way of a single anterolateral incision with standard medial and if necessary, lateral arthrotomies. Ruptures of the cruciate ligaments are reconstructed with absorbable sutures, which are passed through bone channels. Augmentation with an absorbable allograft is used in most reconstructions of the cruciate ligaments. A knee brace with limited range of motion is used for postoperative rehabilitation. Our long-term results after operative reconstruction of acute instabilities of the knee joint show that ligamentous stability was achieved in most cases, but the functional results were impaired by pain and limited range of motion.     

Associated lateral/medial knee instability and its relevant factors in anterior cruciate ligament-injured knees

Background

Associations of lateral/medial knee instability with anterior cruciate ligament (ACL) injury have not been thoroughly investigated. The purposes of this study were to investigate whether lateral/medial knee instability is associated with ACL injury, and to clarify relevant factors for lateral/medial knee instability in ACL-injured knees.

Ligaments of the knee

The ligaments of the knee can be divided into four groups. Ventral reinforcements are the patellar retinaculae. The posteromedial complex stabilizes the valgus stress. It consists of the medial collateral ligament, the thickened posteromedial capsule and a branch of the tendon of the semimembranosus muscle as well as the oblique popliteal ligament. On the lateral side the posterolateral complex protects the knee against varus stress. Here the lateral collateral ligament, the tendon of the popliteus muscle and the so-called popliteofibular fibres work together. The cruciate ligaments control the contact between femoral condyles and tibial plateau during flexion-extension of the knee. They course between the two layers of the capsule, the membranous and the synovial layer.     

Proximal gait adaptations in medial knee OA

The purpose of this study was to examine interlimb differences in gait kinematics and kinetics in patients with symptomatic medial knee OA. The main objective was to identify hip joint movement strategies that might lower the knee adduction moment and also compensate for decreased knee flexion during weight acceptance. Gait analysis was performed on 32 patients with moderate medial compartment knee OA. Kinetic and kinematic data were calculated and side‐to‐side comparisons made. Radiographs were used to identify frontal plane alignment. No interlimb difference in the peak knee adduction moment was found (p = 0.512), whereas a greatly reduced hip adduction moment was seen on the involved side (p < 0.001) during the early part of stance. The involved limb flexed significantly less and hip and knee flexion moments were smaller compared to the uninvolved side. Gait adaptations involving a lateral sway of the trunk may successfully lead to relatively lower ipsilateral knee adduction moments, and would further be reflected by a lower adduction moment at the hip. Subjects did not compensate for less knee flexion by any dynamic means, and likely experience a resulting higher joint impact. These gait adaptations may have implications with respect to development of weakness of the ipsilateral hip musculature and progression of multiarticular OA. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:78–83, 2009     

膝关节韧带损伤的MRI诊断价值

目的:探讨膝关节韧带损伤的MRI特点与诊断价值。方法:收集2008年6月至2010年2月经MRI检查的74例膝关节损伤患者,男47例,女27例;年龄12～76岁,平均37.3岁;病程2h～10d。临床表现为膝关节肿胀、疼痛,关节不稳、伸屈活动障碍,外翻试验、抽屉试验阳性,膝内侧明显压痛。对其MRI表现进行回顾性分析。结果:74例韧带损伤,其中前交叉韧带19例,后交叉韧带18例,外侧副韧带13例,内侧副韧带24例。韧带完全断裂12例,其中8例交叉韧带MR表现为韧带的连续性中断、断端回缩,局部或弥漫性肿胀,PDWI上呈中等信号,T2WI和脂肪抑制序列呈高信号;4例侧副韧带MR表现为韧带连续性中断或韧带肿胀增粗,PDWI上呈中等信号,T2WI和脂肪抑制序列呈高信号。部分纵形撕裂62例,MR表现为韧带连续性完整,韧带增粗,PDWI上呈中等信号,T2WI和脂肪抑制序列呈高信号。经手术、关节镜检查确诊44例,与MRI诊断相符41例。结论:MRI能诊断膝关节韧带损伤,是一种理想的诊断膝关节外伤的检查方法,宜作为常规检查。     

A geometric ratio to predict the flexion gap in total knee arthroplasty

Measured resection is a common technique for obtaining symmetric flexion and extension gaps in posterior-stabilized (PS) total knee arthroplasty (TKA). A known limitation of measured resection, however, is its reliance on osseous landmarks to guide bone resection and component alignment while ignoring the geometry of the surrounding soft tissues such as the medial collateral ligament (MCL), a possible reason for knee instability. To address this clinical concern, we introduce a new geometric proportion, the MCL ratio, which incorporates features of condylar geometry and MCL anterior fibers. The goal of this study was to determine whether the MCL ratio can predict the flexion gaps and to determine whether a range of MCL ratio corresponds to balanced gaps. Six computational knee models each implanted with PS TKA were utilized. Medial and lateral gaps were measured in response to varus and valgus loads at extension and flexion. The MCL ratio was related to the measured gaps for each knee. We found that the MCL ratio was associated with the flexion gaps and had a stronger association with the medial gap (β = −7.2 ± 3.05, P < .001) than with the lateral gap (β = 3.9 ± 7.26, P = .04). In addition, an MCL ratio ranging between 1.1 and 1.25 corresponded to balanced flexion gaps in the six knee models. Future studies will focus on defining MCL ratio targets after accounting for variations in ligament properties in TKA patients. Our results suggest that the MCL ratio could help guide femoral bone resections in measured resection TKA, but further clinical validation is required.     

Intraoperative assessment of tibiofemoral contact stresses in total knee arthroplasty

The production of polyethylene wear debris in total knee arthroplasty (TKA) is due to multiple factors. In particular, inadequate implant alignment and high bearing surface contact stresses are associated with polyethylene failure. Optimal implant placement and soft tissue balancing may contribute to reducing wear and the production of polyethylene particles. We present a case in which a quantitative technique was used to measure tibiofemoral contact stresses during implantation of a total knee prosthesis in vivo. In a knee with preoperative varus and fixed flexion deformity, medial compartment contact stresses after initial resection were reduced from 14.3 MPa to 11.3 MPa in neutral alignment by additional bone resection. Posterior cruciate release was required to reduce contact stresses further and to provide satisfactory balance between medial and lateral compartments, as determined by the operating surgeon, and was confirmed by the measurement system (3.8 MPa medially; 3.0 MPa laterally). This technique has potential to fine-tune implant positioning and ligament balancing during TKA.     

分期修复重建膝关节多发韧带损伤的临床疗效

目的 :探讨关节镜下分期治疗膝关节多发韧带损伤的临床疗效。方法 :2006年3月至2012年6月,关节镜下分期治疗膝关节多发韧带损伤14例(14膝)。男8例,女6例;年龄20~49岁,平均(31.8±8.1)岁。患者均行X线、MR检查,提示10例前交叉韧带、后交叉韧带及内侧副韧带损伤,4例前交叉韧带、后交叉韧带及后外侧角损伤。合并内侧半月板损伤4例,外侧半月板损伤2例。Ⅰ期手术治疗内侧副韧带损伤、后交叉韧带及半月板,术后固定3周后开始主被动功能锻炼,3~6个月后膝关节活动范围正常且存在明显松弛时Ⅱ期重建前交叉韧带和(或)后交叉韧带。结果:术后切口均Ⅰ期愈合,无感染等手术相关并发症发生。患者均获随访,时间24~80个月,平均48.9个月。末次随访时膝关节Lysholm评分达87.1±2.8,优于术前19.6±0.9(t=12.3,P0.01)。国际膝关节评分委员会(International Knee Documentation Committee,IKDC)评级:9例接近正常,5例异常。结论 :关节镜下分期治疗膝关节多发韧带损伤能有效恢复膝关节稳定性和功能。     

Immediate effects of meniscectomy on the knee joint. The effects of tensile load on knee joint ligaments in dogs

Tensile strength variables for the collateral ligaments were compared after excision of the meniscus in one knee, the corresponding meniscus in the contralateral knee of the same dog being intact. Removal of the meniscus was associated with a three-fold increase in initial laxity, two-fold for the lateral and three-fold for the medical ligament. The maximum tensile load uptake of the medial collateral ligament was reduced by more than 10 per cent after medial meniscectomy; the load uptake of the lateral ligament was not affected by lateral meniscectomy. It is proposed that tensile loads are distributed more favourably in the medial collateral ligament by the intact medial meniscus with firm capsular attachments than in the "normal" ligament after meniscectomy.