Gaining exposure during revision total knee arthroplasty (TKA) and primary TKA for the ankylosed knee can be challenging.
Patients undergoing revision TKA are at particular risk for wound healing problems, extensor mechanism rupture, and infection.17
Although over 90% of revision TKA procedures can be performed through a standard surgical approach, the surgeon should be familiar with more extensile techniques in case one must be used to avoid extensor mechanism disruption.6
If adequate exposure is not obtained through a standard surgical approach, a graduated approach is necessary:
Quadriceps snip is used most commonly, followed by tibial tubercle osteotomy, and, rarely, a V-Y quadriceps turndown.
The quadriceps snip has the advantage of requiring no postoperative immobilization or changes to postoperative rehabilitation but may not give adequate exposure in very stiff knees.17
Although it may be possible to perform a prosthetic implantation without using an extensile exposure in the ankylosed knee, quadriceps contracture can limit extensor mechanism excursion, leading to poor postoperative flexion.
V-Y quadricepsplasty may be performed after prosthetic insertion to improve flexion.13
STANDARD APPROACH
Any skin incisions from previous procedures are clearly marked before skin preparation begins.
Although a straight, midline anterior incision is preferred because the vascular supply to the anterior skin of the knee comes primarily from the medial side, the most lateral usable incision is chosen to preserve blood supply to the lateral flap.
It is recommended that a minimum of 6–7 cm distance between the previous and any new incisions be maintained if possible to prevent skin bridge necrosis.7,11
Previous skin incisions are ideally crossed perpendicular to the scar. If this is not possible, they should be intersected at an angle of no less than 60 degrees.
Transcutaneous oxygen tension studies have shown that following skin incision, the inferolateral portion of the skin incision has the lowest oxygen tension, resulting in a decrease in wound healing potential.2,9,10
Thick flaps are developed that include the superficial fascia. Dissection superficial to the fascia should be avoided as the blood supply to the anterior skin of the knee comes from perforating vessels which traverse this fascia and the subcutaneous tissue.2,7,17
A medial parapatellar arthrotomy is made at the junction of the medial and central thirds of the quadriceps tendon.
Subperiosteal dissection of the tibia is extended from the tibial tubercle to the posteromedial corner.
The suprapatellar pouch and the medial and lateral gutters are reestablished, all adhesions are released, and a thorough synovectomy is performed.
All peripatellar scar tissue is removed.
Prior to flexion of the knee, the patellar tendon may be stabilized with a pin, towel clip, or small staple placed into the tibial tubercle to prevent patellar tendon avulsion.11
The knee is gently flexed while the tibia is externally rotated and subluxed laterally. These maneuvers reduce tension on the extensor mechanism.
If the extensor mechanism is still under too much tension, a lateral retinacular release may be performed from inside out, making sure to preserve the lateral superior genicular artery, which is now the primary blood supply to the patella.
If adequate exposure is still not possible, a quadriceps snip is performed.
In most revision TKAs, adequate exposure can be obtained with these maneuvers.11
TECHNIQUES
Tibial Tubercle Osteotomy
Tibial tubercle osteotomy (see Chap. 44) is chosen in cases with difficulty in stem or cement extraction or in patients with patella baja.5
Potentially serious complications of this procedure include proximal migration of the tibial tubercle as well as tibial tubercle nonunion.14,16
Other common complications include tibial tubercle pain and prominent hardware following fixation. These are often successfully treated with removal of hardware following tibial tubercle union.4,14
Quadriceps Turndown
The quadriceps tendon is exposed proximal to the insertion of the vastus lateralis and medialis muscles.
The medial parapatellar arthrotomy is extended proximally to the insertion of the vasti.
The quadriceps is then incised distally and laterally at an angle of about 45 degrees along the insertion of the vastus lateralis (TECH FIG 1).
This inverted V incision creates a distally based flap that includes the patella. Essentially, the medial arthrotomy is connected to the lateral release.
Care should be taken to preserve the lateral superior geniculate artery.
The patella is now “turned down” anterolaterally, providing excellent exposure to the joint.
V-Y Quadricepsplasty
This procedure is indicated to increase postoperative flexion.
The quadriceps is repaired in situ with multiple interrupted no. 2 nonabsorbable sutures and range of motion (ROM) is assessed.
If ROM is acceptable, closure is completed, leaving the lateral retinacular release open.
If increased passive ROM is desired, the V is converted to an inverted Y.
The knee is flexed and sutures or clamps are placed along the apex of the Y.
Once appropriate lengthening is established, no. 2 nonabsorbable sutures are used to close the medial side of the quadriceps mechanism.
The lateral retinacular release (lateral limb of the Y) is left open.
The lateral limb of the quadricepsplasty is covered by closing the quadriceps mechanism to the superficial fascia of the vastus lateralis (TECH FIG 2).
The maximum flexion of the knee that will not put undue tension on the repair is recorded prior to routine skin closure.
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POSTOPERATIVE CARE
One disadvantage of V-Y quadricepsplasty is the necessity to modify postoperative rehabilitation.
Maximum passive flexion to avoid tension on the repair is determined intraoperatively after capsular closure. This is not exceeded in the first 2 weeks.
The patient is place in a knee immobilizer immediately postoperatively.
A hinged knee brace is fitted after the first dressing change. A flexion stop is used for the first 2 weeks.
Passive knee extension and active knee flexion are done for 6 weeks.
Partial weight bearing is required for 6 weeks.
The brace is locked in extension at night and with ambulation until the extensor lag is less than 15 degrees.
OUTCOMES
Knee scores are similar to those of patients who have had revision TKA and reflect the difficulty of knees that need this procedure.1,15
A study comparing patients who underwent quadriceps turndown and tibial tubercle osteotomy to patients whose revision TKAs were performed with routine exposure found patients in the quadriceps turndown and tibial tubercle osteotomy groups had equivalent postoperative scores, which were significantly lower than those of patients in the routine exposure revision TKA group. The turndown group had a higher increase in ROM than the osteotomy group, but they also had a higher degree of extensor lag. The turndown group also had a lower percentage of patients who considered their surgery unsuccessful in relieving pain and return of function and a lower percentage of patients who had difficulty with kneeling and stooping.3
A prospective randomized controlled trial with 8 years minimum follow-up comparing quadriceps snip to tibial tubercle osteotomy for revision TKA cases for prosthetic knee infection found patients undergoing tibial tubercle osteotomy had significantly higher Knee Society Scores, higher postoperative knee flexion, and lower postoperative extension lag. All patients in the tibial osteotomy group showed radiographic evidence of tibial tubercle healing, 11 patients had pain over the tibial tubercle at 6 months, and 8 elected to undergo removal of fixation hardware and were pain free at 1 year.4
One study evaluating the effectiveness of V-Y quadricepsplasty found an average increase in postoperative flexion of 49 degrees, with an overall increase in postoperative ROM to 52 degrees. The patients also had average postoperative extensor lag of 8 degrees.13
Trousdale et al15 evaluated functional outcomes following V-Y quadricepsplasty found a trend toward knee extension weakness, but this only reached statistical significance at knee extension test speeds of 120, 180, and 240 degrees per second. Overall, the extensor weakness did not appear to be clinically significant.15
In a mixed population of primary and revision TKA, Cybex testing revealed that the quadriceps was weaker on the V-Y quadricepsplasty side, but this did not reach statistical significance. Only 5 of 14 patients had extensor lag greater than 5 degrees, with active extension lag averaging 4 degrees (range 0 to 20 degrees).15
A study of patients undergoing TKA with preoperative knee stiffness (defined as preoperative ROM <50 degrees) found that patients requiring the V-Y quadricepsplasty intraoperatively to increase ROM had a significantly higher rate of postoperative extensor lag greater than 10 degrees. However, these patients also had significantly lower preoperative knee function scores and ROM and higher incidence of flexion contracture.8
COMPLICATIONS
As detailed and referenced above. Mainly extensor lag and mild extensor weakness of questionable clinical significance.
Additionally, patellar osteonecrosis was observed in 8 of 29 patients with quadriceps turndown in one study.12
One case of minor wound dehiscence was also reported in a hemophiliac patient during manipulation under anesthesia after TKA using V-Y quadricepsplasty.
REFERENCES
1. Aglietti P, Buzzi R, D’Andria S, Scrobe F. Quadricepsplasty with the V-Y incision in total knee arthroplasty. Ital J Orthop Traumatol 1991;17(1):23–29.
2. Aso K, Ikeuchi M, Izumi M, et al. Transcutaneous oxygen tension in the anterior skin of the knee after minimal incision total knee arthroplasty. Knee 2012;19(5):576–579.
3. Barrack RL, Smith P, Munn B, et al. The Ranawat Award. Comparison of surgical approaches in total knee arthroplasty. Clin Orthop Relat Res 1998;(356):16–21.
4. Bruni D, Iacono F, Sharma B, et al. Tibial tubercle osteotomy or quadriceps snip in two-stage revision for prosthetic knee infection? A randomized prospective study. Clin Orthop Relat Res 2013;471(4):1305–1318.
5. Clarke HD, Scuderi GR. Revision total knee arthroplasty: planning, management, controversies, and surgical approaches. Instr Course Lect 2001;50:359–365.
6. Della Valle CJ, Berger RA, Rosenberg AG. Surgical exposures in revision total knee arthroplasty. Clin Orthop Relat Res 2006;446:59–68.
7. Garbedian S, Sternheim A, Backstein D. Wound healing problems in total knee arthroplasty. Orthopedics 2011;34(9):e516–e518.
8. Hsu CH, Lin PC, Chen WS, et al. Total knee arthroplasty in patients with stiff knees. J Arthroplasty 2012;27(2):286–292.
9. Johnson DP. Midline or parapatellar incision for knee arthroplasty. A comparative study of wound viability. J Bone Joint Surg Br 1988;70(4):656–658.
10. Johnson DP, Houghton TA, Radford P. Anterior midline or medial parapatellar incision for arthroplasty of the knee. A comparative study. J Bone Joint Surg Br 1986;68(5):812–814.
11. Laskin RS. Ten steps to an easier revision total knee arthroplasty. J Arthroplasty 2002;17(4)(suppl 1):78–82.
12. Parker DA, Dunbar MJ, Rorabeck CH. Extensor mechanism failure associated with total knee arthroplasty: prevention and management. J Am Acad Orthop Surg 2003;11(4):238–247.
13. Scott RD, Siliski JM. The use of a modified V-Y quadricepsplasty during total knee replacement to gain exposure and improve flexion in the ankylosed knee. Orthopedics 1985;8(1):45–48.
14. Tabutin J, Morin-Salvo N, Torga-Spak R, et al. Tibial tubercule osteotomy during medial approach to difficult knee arthroplasties. Orthop Traumatol Surg Res 2011;97(3):276–286.
15. Trousdale RT, Hanssen AD, Rand JA, et al. V-Y quadricepsplasty in total knee arthroplasty. Clin Orthop Relat Res 1993;(286):48–55.
16. Young CF, Bourne RB, Rorabeck CH. Tibial tubercle osteotomy in total knee arthroplasty surgery. J Arthroplasty 2008;23(3):371–375.
17. Younger AS, Duncan CP, Masri BA. Surgical exposures in revision total knee arthroplasty. J Am Acad Orthop Surg 1998;6(1):55–64.
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