RECONSTRUCTION 2023, Jan, 08 | 12:00 am

Quadriceps-Sparing Total Knee Arthroplasty

‏ف ‏‏إيت فولز ‏

  • ‏الذكر الطويل العضلي ذو الأوعية الدموية الإنسية منخفضة الإدخال على الجانب الإنسي من الرضفة هو حالة صعبة.‏

     

  • ‏الركبة مع الرضفة باجا صعبة ويجب تجنبها.‏

     

  • ‏بعض المرضى لديهم أنسجة رخوة "ضيقة" تعطي القليل جدا وتجعل التعرض للركبة صعبا بشكل عام.‏

     

  • ‏الركبة التي تعمل بالمضاعفة ، حتى لو كانت الإجراءات كلها‏

‏تنظير المفصل ، يمكن أن يكون في بعض الأحيان ما يكفي من التندب لجعل النهج صعبا.‏

 

‏TKA تجنيب عضلات الفخذ‏

 

‏مؤشرات‏

  • ‏يشار إلى الإجراء في المرضى الذين خضعوا بالفعل لجميع التدابير المحافظة ويحتاجون الآن إلى استبدال الركبة.‏

  • ‏تعتبر الركبة المصابة بالتهاب المفاصل مثالية لأن مخزون العظام جيد دون دليل على هشاشة العظام. قد تحتوي الركبة المصابة بالتهاب المفاصل الالتهابي على أسطح عظمية أكثر ليونة تنهار قليلا مع التراجع ويجب تقييمها بعناية قبل الجراحة.‏

  • ‏يجب أن يكون للركبة نطاق حركة لا يقل عن 105 درجة مع ما لا يزيد عن 10 درجات من التباين الثابت ، و 15 درجة من الأروح الثابتة ، و 10 درجات من تقلص الانثناء. يجب ألا يحتوي على شقوق سابقة لبضع المفصل ، مثل قطع العظم السابق.‏

  • ‏يجب أن يزن المريض أقل من 225 رطلا.‏

    ‏الخلافات‏

    • ‏يشعر العديد من الجراحين أنه لا يمكن إجراء العملية بدقة من خلال مثل هذا الشق الصغير.‏

    • ‏يعتقد بعض الجراحين أن الأوعية الدموية الإنسية تدخل في الجزء الأوسط من الرضفة في جميع الحالات ، وأن إجراء تجنيب عضلات الفخذ لا يمكن أن يتجنب قطع هذه العضلة ، مما يجعل تقنية التجنيب مستحيلة. ومع ذلك ، فإن الأدبيات مثيرة للجدل للغاية فيما يتعلق بهذا الموضوع.‏

     

  • ‏يمكن بناء نسبة تقسم طول الفخذ من العمود الفقري الحرقفي العلوي الأمامي للحوض على محيط الركبة على مستوى الرضفة. الرقم بين 2 و 3 مثالي. أي شيء أقل من 2 سيكون ركبة أكثر صعوبة بسبب الأنسجة الرخوة المحيطة.‏

  • ‏يجب أن تكون الرضفة في الارتفاع الطبيعي ، ويجب أن يكون إدخال الأوعية الإنسية في القطب العلوي للرضفة أو أعلى.‏

    ‏الفحص / التصوير‏

  • ‏يجب أن يتضمن التقييم الشعاعي منظرا أماميا خلفيا (AP) قائما جنبا إلى جنب مع مناظر جانبية وأفقية.‏

    ‏خيارات العلاج‏

    • ‏يمكن إجراء النهج الجراحي الذي يحافظ على عضلات الفخذ ل TKA من خلال شق نصف رضفي وسطي محدود. يمتد الشق الإنسي من القطب العلوي للرضفة إلى‏

      ‏2 سم تحت خط المفصل الظنبوبي (الشكل 2).‏

    • ‏في بعض الأحيان ، يمكن استخدام الشق الجانبي للركبة الأروح.‏

    • ‏تشمل الطرق المحدودة الأخرى للركبة subvastus و midvastus وبضع المفصل المصغر ، والتي تستخدم جميعها نهجا وسطيا.‏

     

    • ‏تظهر صورة شعاعية دائمة للركبة (الشكل 1A) المحور التشريحي.‏

    • ‏تظهر الصورة الشعاعية الجانبية (الشكل 1B) ارتفاع الرضفة ومنحدر الظنبوب. الرضفة ألتا هي موانع نسبية لتقنية تجنيب عضلات الفخذ.‏

  • ‏من المثالي أن يكون لديك عرض طويل للمحور الميكانيكي AP للساق ، لكن هذا ليس إلزاميا. يجب ألا يزيد التباين التشريحي عن 10 درجات وألا يزيد أروح عن 15 درجة.‏

  • ‏إذا كانت هناك مسألة نخر الأوعية الدموية أو عدم الاستقرار غير المبرر ، يمكن الإشارة إلى التصوير بالرنين المغناطيسي ، ولكن هذا ليس اختبارا روتينيا.‏

     

     

     

     

     

    ‏TKA تجنيب عضلات الفخذ‏

     

     

     

     

     

    121

     

    A

    ‏الشكل 1‏

     

    B

     

    ‏الشكل 2‏

     

     

     

     

    122

     

    ‏TKA تجنيب عضلات الفخذ‏

     

    ‏الشكل 3‏

     

    ‏التشريح الجراحي‏

  • ‏مجال القلق الرئيسي في جميع الأساليب المحدودة هو الأوعية الإنسية.‏

  • ‏يمكن أن يدخل بطن العضلات عاليا فوق الرضفة أو في القطب العلوي (الشكل 3) ، أو في المستوى المتوسط.‏

  • ‏العضلة منخفضة الإدخال غير شائعة وتجعل التعرض صعبا للغاية. غالبية الركبتين لديها إدخال في القطب العلوي وقابلة للنهج.‏

     

    P EARLS

    • It is difficult for any assistant to hold the knee in the midzones of flexion as opposed to 0° and 90°.

     

    Positioning

  • The patient is positioned supine on the operating room table.

  • It is best to use a leg holder (e.g., Innovative Medical Products, Plainville, CT) so that the knee can be positioned in various degrees of flexion from 20°

    ‏الخلافات‏

    • Many surgeons believe that the leg holder is an expensive device that is unnecessary. However, it is most often a single-time expense and helps to eliminate an additional surgical assistant in the operating room.

     

    to 70°, where most of the surgical procedure is performed (Fig. 4). The standard TKA is typically positioned at 0° and 90° for most of the operation, and this is not at all the case in the quad-sparing approach.

     

     

     

    123

     

    ‏TKA تجنيب عضلات الفخذ‏

     

    ‏الشكل 4‏

     

    Portals/Exposures

    • The skin incision can be a curved one around the medial aspect of the patella or a straight one that is positioned just medial to the patella (see Fig. 2).

       

      P EARLS

      • The benefits of the straight versus curved incision are determined more by the arthrotomy and treatment of the underlying extensor mechanism. The curved incision is a more utilitarian approach and readily accommodates extensile exposure.

         

        ‏ف ‏‏إيت فولز ‏

      • Increased tension with retractors in an attempt to improve visualization often results in less rather than more exposure.

       

    • The length of the incision is determined by the height of the patient and the difficulty of the exposure. If the knee is particularly tight, it is better to extend the incision to avoid skin compromise.

    • Simple retractors are used for the approach, and the skin incision must be moved in all directions as a “mobile window.”

    • The arthrotomy begins from the superior pole of the patella and extends to 2 cm below the joint line.

      • It can be extended up to 2 cm into the quadriceps tendon without changing the operative result.

      • Extension beyond the 2-cm level will convert the result more to a standard outcome with slightly greater blood loss.

    • The fascia beneath the vastus medialis can be incised at the superior margin of the arthrotomy incision, which increases the exposure without violating the vastus medialis muscle itself.

     

     

    P EARLS

    • It is not necessary to resurface the patella; however, if the knee is particularly tight and the exposure is difficult, resection of the patellar surface does facilitate the exposure.

       

    • It is helpful to keep the knee in the midportion of the range of motion from 20° to 70° throughout most of the operative procedure to enable soft tissue retraction.

       

      ‏ف ‏‏إيت فولز ‏

    • No more than two retractors should be placed into the wound at any given time. The retraction is critical with the limited exposure, and increased force on any one retractor usually decreases the actual view.

     

    Procedure

    Step 1

    • The deep medial collateral ligament is released from the proximal tibia, and the fat pad is excised to increase the exposure (Fig. 5). The patellar thickness is measured, but the surface is not resected at this time.

    • The synovium is removed from the anterior surface of the femur, and the knee is flexed to 70°.

    • The incision should be treated as a mobile window.

      • It can be moved with two retractors either medial to lateral or superior to inferior, facilitating the view of the specific area of the knee that is undergoing surgery at that time.

      • It is seldom possible to see the entire knee through this exposure, and the surgeon must allow for that.

        124

         

        ‏TKA تجنيب عضلات الفخذ‏

         

        Step 2

    • The AP axis of the femur (Whiteside’s line) is drawn for rotational alignment of the femoral cuts (Fig. 6).

    • The intramedullary hole is made in the midline just above the roof of the intercondylar notch.

       

      P EARLS

      • Care must be taken to avoid notching the anterior cortex of the femur, but, at the same time, it is important to set the anterior cut as close to the cortical surface as possible to decrease the patellofemoral forces across the knee after surgery.

         

        P ITFALLS

      • The difficulty with custom instruments is the lack of familiarity for the operating surgeon and the resultant decrease in the accuracy of the cuts.

       

    • The intramedullary reference rod is inserted with the appropriate chosen valgus angle (from 3° to 7°). The angle is determined by measuring the difference between the anatomic and mechanical axis of the preoperative knee.

      • The rotational alignment is set using the “flag” on the instrument. The flag, with the arrow pointing superior, is aligned with Whiteside’s line for rotation of the subsequent cuts (Fig. 7).

         

         

         

        FIGURE 5

         

         

         

         

         

        Quadriceps-Sparing TKA

         

         

         

        125

         

        FIGURE 6

         

        FIGURE 7

         

         

         

         

        Quadriceps-Sparing TKA

         

        FIGURE 8

         

        126

         

      • Once this is pinned in place, the depth of the anterior femoral resection is set using a reference arm. The reference arm is set in the cutting slot and used to show where the cut will exit on the anterior cortex of the femur to avoid notching (Fig. 8).

    • The distal femoral cut can be made either from the medial side of the femur or from anterior.

      • The cut can be made using a medially based guide that requires less lateral retraction of the extensor mechanism (Fig. 9A). With the medial-based cut, it is easier to fit the saw blade into the arthrotomy, but this cut does result in some inaccuracy across the lateral femoral condyle because of the distance involved.

      • The cut can also be made with a more traditional cutting guide that allows the surgeon to cut from anterior to posterior (Fig. 9B). The anterior-based cut is familiar to the surgeon and slightly more accurate, but does require more soft tissue retraction.

    • The procedure can be performed with custom instruments that are designed to fit into the small space with greater ease.

      • The distal femur can be resected first from the medial side using a custom instrument that has

 

 

 

Quadriceps-Sparing TKA

 

A B

FIGURE 9

 

127

 

cutting slots that capture the saw blade from the medial side (Fig. 10A).

  • The anterior resection can be completed with a custom instrument that has foot pads that contact the posterior femoral condyles and allows the cutting slot to be moved anterior to posterior on the tower to reference the anterior femoral cortex and avoid notching (Fig. 10B).

 

 

 

A B

FIGURE 10

 

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Quadriceps-Sparing TKA

 

  • The custom femoral finishing block is set into the knee in full extension with the attached plate resting on the previously cut anterior surface (Fig. 11A).

  • The knee is flexed to 70° with the custom block pinned to the anterior femoral surface (Fig. 11B). The final cuts are completed in this position.

  • The depth of the femoral resection is determined by the extent of the preexisting flexion contracture.

    It should be deepened by 2 mm if there is a 5° or greater flexion contracture for a planned posterior-stabilized TKA and if there is 10° or greater flexion contracture for a planned cruciate-retaining TKA.

  • After the anterior and distal femoral cuts are completed, the femur can be sized for the final component.

  • The finishing block is placed on the distal femoral cut surface with reference to the anterior cortex (Fig. 12), and the cuts are completed.

     

     

     

     

     

    A

    FIGURE 11

     

    B

     

     

     

     

     

    Controversies

    • The use of intramedullary instruments for both the femur and the tibia can be criticized because this can increase the possibility of fat embolism and bleeding.

     

    Step 3

    FIGURE 12

    • The tibial resection is completed with an extramedullary instrument that can reference the depth of the resection, the varus-valgus angle, and the slope of the cut. The extramedullary guide slides around the medial aspect of the tibia, as seen in Figure 13 via a mini-incision used to fully show the instrument.

    • Intramedullary instruments are available, but they are difficult to insert in the small arthrotomy and they cannot be used in some valgus knees where there is a valgus angle to the tibial shaft.

       

       

       

      129

       

      FIGURE 13

      Quadriceps-Sparing TKA

       

       

       

       

      130

       

      Quadriceps-Sparing TKA

       

      FIGURE 14

       

  • At one point in its development, the extramedullary tibial cutting device was set on an outrigger that permitted a pure medial approach to the tibial cut (Fig. 14), which made the positioning of the jig much easier. The proximal tibial resection could be completed with a medially based guide that requires less lateral retraction. However, the longer saw blade that is necessary for this cut can introduce inaccuracy on the lateral tibial plateau side because of the increased distance from the cutting slot.

    Step 4

  • After the femoral and tibial resections are completed, a spacer block with extramedullary rods can be inserted into the knee at 90° of flexion and at full extension, and the gaps can be compared and corrected if necessary (Fig. 15). The alignment of all surfaces is also checked at this point.

  • If a cruciate-retaining knee is planned, the cuts on

    the femur are already completed and the tibia can now be addressed.

  • If a posterior-stabilized design is chosen, the box cut on the femur should be completed at this time.

     

     

     

    Quadriceps-Sparing TKA

     

    FIGURE 15

     

    131

     

    Step 5

    • The final tibial preparation is completed by placing the tibial guide plate on the top of the cut surface and centering it first in the coronal plane (Fig. 16). This can sometimes be difficult because of the limited exposure of the posterior lateral aspect. The knee should be flexed to 70° (not 90° as in the traditional TKA), and the lateral retractors placed first.

       

       

       

      FIGURE 16

       

      Quadriceps-Sparing TKA

       

  • A smooth Hohmann retractor can be placed in the midline of the tibia (or on either side of the posterior cruciate ligament if a cruciate-retaining knee is planned) and used to shift the tibia slightly anterior to the femoral cut surface. The tibial flanges and the central hole can then be completed.

  • It can be difficult to insert a traditional tibial component (Fig. 17A), and gentle manipulation of the soft tissues becomes extremely important.

     

     

     

    132

     

    A

     

     

     

    B

    FIGURE 17A

     

    133

     

    Quadriceps-Sparing TKA

     

    • ”MIS”-type tibial components such as that made by Smith and Nephew (Memphis, TN; Fig. 17B) have an abbreviated intramedullary stem that facilitates component insertion without compromising the fixation.

    • These designs are helpful but not completely necessary if the surgeon develops some experience with the soft tissue retraction.

      • The patellar resection can also be completed at this time. It is easier to perform because the surfaces of the femur and tibia have been resected, leaving more space for manipulation of the extensor mechanism.

    • If necessary, the patella can actually be everted in full extension without difficulty. The resurfacing should usually decrease the original thickness by 2 mm.

    • The patellar resection clamp made by Zimmer (Warsaw, IN) allows the surgeon to determine the amount of bone that will be resected and fits easily into the limited incision (Fig. 18).

      Step 6

      • The components are usually cemented; however, this is not a requirement of the technique, and a cementless femur is certainly easier to work with.

    • In the cruciate-retaining design, the tibial component is cemented with the polyethylene and the femur is inserted over the plastic into position on the distal femur.

     

     

     

    FIGURE 17

     

     

     

    Quadriceps-Sparing TKA

     

    FIGURE 19

     

    134

     

    • In the posterior-stabilized design, the tibial tray is cemented first. The femur is then cemented, and the polyethylene is inserted last.

  • The patella is inserted as the final component if the surface is replaced.

  • The tourniquet is released before closure of the arthrotomy, and the closure is completed in the standard fashion. The incision is usually 8 to 12 cm (Fig. 19). This is determined by the size of the patient and the bony landmarks.

     

    P EARLS

    • Patients have less blood loss, less pain, and more motion than the standard TKA patient.

     

    Postoperative Care and Expected Outcomes

  • The knee is only covered with a light dressing and an elastic bandage.

  • The author uses drains for Cell Saver salvage of the blood after surgery. The drains are removed on the morning after the operation.

  • Full physical therapy is instituted on the afternoon of surgery, including weight bearing as tolerated and range of motion.

  • Anticoagulation is started 24 hours after surgery, and Doppler ultrasound surveillance is used for all patients. The anticoagulation is continued for

    14 days.

  • Patients usually have full range of motion within 6–8 weeks after surgery. If the patient does not obtain 90° of motion by 6 weeks after surgery, a manipulation of the knee may be necessary.

 

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Quadriceps-Sparing TKA

 

Evidence

Bonutti PM, Mont MA, McMahon M, Ragland PS, Kester M. Minimally invasive total knee arthroplasty. J Bone Joint Surg [Am]. 2004;86(Suppl 2):26-32.

 

This article reviews the authors’ experience with the mini-midvastus approach and summarizes the results well.

 

Chen AF, Alan RK, Redziniak DE, Tria AJ: Quadriceps sparing total knee arthroplasty: initial experience with two to four year results. J Bone Joint Surg [Br]. 2006;88:1448-53.

 

This article reviews the authors’ experience with the quadriceps sparing approach and indicates that it does have benefits for the patient but with some loss of implant accuracy.

 

Huang HT, Su JY, Chang JK, Chen CH, Wang GJ. The early clinical outcome of minimally invasive quadriceps-sparing total knee arthroplasty: report of a 2-year follow-up. J Arthroplasty. 2007;22:1007-12.

 

The authors report that the quadriceps sparing approach has distinct benefits but there is an associated learning curve with more outliers with the technique.

 

Kim YH, Kim JS, Kim DY. Clinical outcome and rate of complications after primary total knee replacement performed with quadriceps-sparing or standard arthrotomy. J Bone Joint Surg [Am]. 2007;89:467-70.

 

This group reports more complications with the quadriceps sparing technique and suggests that the surgeon use the smallest incision that is practical in each case with a standard approach.

 

King J, Stamper DL, Schaad DC, Leopold SS. Minimally invasive total knee arthroplasty compared with traditional total knee arthroplasty: assessment of the learning curve and the postoperative recuperative period. J Bone Joint Surg [Am]. 2007;89:1497-503.

 

This article reviews the authors’ experience with the quadriceps sparing approach and emphasizes that there is an associated learning curve with the surgery.

 

Romanowski MR, Repicci JA. Minimally invasive unicondylar arthroplasty: eight-year follow-up. J Knee Surg. 2002;15:17-22.

 

The authors report their experience with a limited approach for UKA with 10 revisions (7%) over 8 years of follow-up.

 

Scuderi GR, Tenholder M, Capeci C. Surgical approaches in mini-incision total knee arthroplasty. Clin Orthop Relat Res. 2004;428:61-7.

 

The authors show that the mini arthrotomy for TKA is just as accurate as the standard incision and does have some less blood loss.

 

Tanavalee A, Thiengwittayaporn S, Itiravivong P. Progressive quadriceps incision during minimally invasive surgery for total knee arthroplasty: the effect on early postoperative ambulation. J Arthroplasty. 2007;22:1013-18.

 

The authors show that the quadriceps sparing technique can be modified with up to a 2 cm incision into the quadriceps tendon without any change in the clinical result versus the original quadriceps sparing operation.