AMERICAN ACADEMY OF ORTHOPAEDIC SURGEONS
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Adult Reconstructive
Surgery of the
Hip and Knee I
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Answer Book
, 2025 Adult Reconstructive Surgery of the Hip and Knee Examination Answer Book · 7
Question 1
During the course of a revision total knee arthroplasty via a medial parapatellar exposure, the surgeon
does a complete intra-articular release and synovectomy but exposure is still inadequate. A quadriceps
snip is performed and, at the end ofthe procedure, the knee is stable throughout a range of motion and
the postoperative radiographs show acceptable alignment of the components. The patient's postoperative
physical therapy regimen should include which of the following?
1. No restriction in range of motion or weight bearing after surgery.
2. Limit flexion to 30 degrees postoperatively, progressing 1 0 degrees per week
3. Limit flexion to 90 degrees for the first 6 weeks postoperatively
4. Limit to active flexion only with no passive flexion or active extension for 6 weeks
5. Use of a hinged knee brace for 6 weeks postoperatively
PREFERRED RESPONSE: 1
DISCUSSION: A quadriceps snip is performed by extending a medial parapatellar approach superiorly
and laterally across the quadriceps tendon. It is then repaired primarily at the end of the procedure. The
primary advantage of this technique over other surgical maneuvers that improve exposure at the time of
revision total knee arthroplasty is that the postoperative regimen for physical therapy does not need to be
altered.
REFERENCES: Younger AS, Duncan CP, Masri BA: Surgical exposures in revision total knee arthroplas-
ty. J Am Acad Orthop Surg 1 998;6:55 -64.
Della Valle CJ, Berger RA, Rosenberg AG: Surgical exposures in revision total knee arthroplasty. Clin
Orthop Relat Res 2006;446 : 59-68.
Barrack RL , Smith P, Munn B, et al: The Ranawat Award. Comparison of surgical approaches in total
knee arthropl asty. Clin Orthop Relat Res 19 98;3 56: 16-2 1 .
Question 2
A healthy 72-year-old woman is seen 14 days after cemented total knee arthroplasty. She reports
increasing pain and swelling for the last 4 days accompanied by 4 days of wound drainage. Examination
reveals that she is afebrile, and has erythema and moderate serosanguinous drainage from the wound. The
knee is moderately swollen. Aspiration of the knee reveals no organisms on Gram stain. Culture results
are expected back in 48 hours. Optimal management should consist of
1. initiation of a first-generation cephalosporin while awaiting culture results.
2. initiation of broad-spectrum antibiotics while awaiting culture results.
3. ultrasound to evaluate for fluid collection around the knee.
4. surgical debridement of the knee before culture results are available.
5. inpatient observation and no antibiotics until culture results are available.
PREFERRED RESPONSE: 4
,8 • American Academy of Orthopaedic Surgeons
DISCUSSION: Increased pain, swelling, erythema, and drainage 2 weeks removed from the primary
arthroplasty are all signs of a probable infection. Erythrocyte sedimentation rate and C-reactive protein
may not be helpful as they are elevated postoperatively even in the absence of infection. Even in the
absence of infection, persistent wound drainage is an indication for surgical debridement to prevent
subsequent infection. When a postoperative infection is easily recognized by clinical examination, there is
no need to wait for a positive culture before proceeding with debridement.
REFERENCES: Weiss AP, Krackow KA: Persistent wound drainage after primary total knee arthroplasty.
J Arthroplasty 1 993;8 :285-289 .
laberi FM, Parvizi J, Haytmanek CT, et al: Procrastination of wound drainage and malnutrition affect the
outcome of joint arthroplasty. Clin Orthop Relat Res 20 08 ;466 :13 68 -1 3 7 1 .
Insall IN, Windsor RE, Scott, WN: Surgery ofthe Knee, ed 2 . New York, NY, Churchill Livingstone,
1 993, pp 959-964.
Figure 3a Figure 3b
Question 3
A 72-year-old woman underwent a primary total hip arthroplasty 14 months ago. She states that the hip
has now dislocated four times when rising from a low chair, requiring closed reduction. A radiograph is
shown in Figure 3a and a CT scan of her pelvis is shown in Figure 3b. What is the most re1iable method
for rectifying her instability?
1. Use of an abduction orthosis for 6 weeks
2. Modular exchange of the femoral head to a 36-mm head and a longer neck
3. Modular exchange ofthe polyethylene liner to a constrained acetabular insert
4. Revision and repositioning of the acetabular component and use of a 36-mm femoral
head
5. A physical therapy program stressing abductor strengthening
PREFERRED RESPONSE: 4
DISCUSSION: The radiograph shows well-fixed components without evidence of loosening. The CT scan
shows severe retroversion of the acetabu1ar component. Revision of the component into the correct amount
of anteversion will most reliably rectify the instability in the face of severe component malposition.
, 2010 Adult Reconstmctive Surgery ofthe Hip and Knee Examination Answer Book· 9
REFERENCES: Parvizi J, Pidnic E, Sharkey PF: Revision total hip arthroplasty for instability: Surgical
techniques and principles. J Bone Joint Surg Am 2008;90: 1134- 1 142.
DeWal H, Su E, DiCesare PE: Instability following total hip arthroplasty. Am J Orthop 2003;32: 377-382.
Barrack RL, Booth RE Jr, Lonner lH, et al (eds) : Orthopaedic Knowledge Update: Hip and Knee
Reconstruction 3. Rosemont, IL, Amelican Academy of Orthopaedic Surgeons, 2006, pp 475-503.
Question s4
A spatient swith sa shistory sof srheumatoid sarthritis sreports sa spainful stotal ship sarthroplasty s3
syears safter sthe sindex sprocedure. s Radiographs sreveal sloosening sof sthe sfemoral scomponent.
s Preoperative sblood swork sshows san serythrocyte ssedimentation srate s(ESR) sof s38 smmlh s(nOlmal
s0-29 smmlh) sand sa sC-reactive sprotein s(CRP) sof s8.9 s(0.2-8.0). s W shat sis sthe smost sappropriate
saction sat sthis stime?
1. Technetium sbone s scan
2. Hip saspiration s for s culture
3. FDG-PET s scan
4. Surgery s with sno sfurther sinvestigations
5. Revision ssurgery sand sobtain san sintraoperative sfrozen
ssection sPREFERRED sRESPONSE: s2
DISCUSSION: s The squestion scenters son sthe sappropriate swork-up sfor sa sfailed stotal ship
sarthroplasty sprior sto srevision ssurgery. s The spreoperative sESR sis selevated sand sthe sCRP sis sat
sthe supper send sof snormal. s If s either sthe sESR sor sCRP sis selevated, sfurther sinvestigations sare
srequired sto sexclude sinfection sas sa scause sof s loosening, sparticularly sin sa spatient sonly s3
syears safter sthe sindex sprocedure. s A stechnetium sscan salone sis s nonspecific sand swill sshow
sincreased suptake sbecause sof sthe sloose sfemoral scomponent. s An sintraoperative
frozen ssection sis sa shelpful sconfirmatory sinvestigation, sbut swhenever spossible sthe sdiagnosis sshould
sbe smade spreoperatively sto sallow sfor sappropriate ssurgical splanning. s Recently, s investigators shave
sshown sthe svalue sof sFDG-PET s scanning sas s a s useful sinvestigation s for sdiagnosing s infection;
s however, s it sis sno s more saccurate s than sthe s combined s use s of san s ESR s and s CRP, s and s does
s not s allow s for s identification s of san s infecting s organism. s At sthis spoint, sa ship saspiration sfor
sculture sis sthe smost sappropriate sinvestigation.
REFERENCES: sBauer sTW, sParvizi sJ, sKobayashi sN, set sal: sDiagnosis sof speriprosthetic sinfection.
s J sBone sJoint sSurg sAm s2006;88:869-882.
Pill sSG, sParvizi sJ, sTang sPH, set sal: s Comparison soffiuorodeoxyglucose spositron semission
stomography sand s(s11 s1)indium-white sblood scell simaging sin sthe sdiagnosis sof speriprosthetic
sinfection sof sthe ship. s J sArthroplasty s2006;21:91-97.
Spangehl sMJ, sMasri sBA, sO'Connell sJX, set sal: s Prospective sanalysis sof spreoperative sand
sintraoperative sinvestigations sfor sthe sdiagnosis sof sinfection sat sthe ssites sof stwo shundred sand
stwo srevision stotal ship sarthroplasties. s J sBone sJoint sSurg sAm s 1999;8 s1:672-683.