The Stiff Total Knee Replacement: Causes, Treatment, and Prevention

1
The Stiff Total Knee Replacement Causes,
Treatment, and Prevention

• N. Johanson, M.D.
• I.C.L. Ch. 46, 1997
• Reviewed by K. Ikram, D.O.

2
Introduction

• Stiffness is observer dependent
• From surgeons perspective, it is inadequate or
  less than expected ROM
• Pt who has 90 deg flexion, and within 10 deg of
  full ext and no complaints of pain or fxnal
  difficulties in not considered to have a stiff
  knee

3

• If after 1 yr post op, pt has following problems,
  must evaluate for underlying knee problems
• C/o knee stiffness
• Difficulty getting out of chair
• Pain on climbing stairs
• Stiff knee gait

4

• Stiffness is closely related to the pts own
  motivation to gain a fxnal ROM, and his or her
  willingness to endure pain to achieve that goal.
• Stiffness is nearly always present during early
  postop period, gradually dec over time, and is a
  valuable marker of improvement throughout the
  recovery period
• Surgical pain is the most imp cause of early knee
  stiffness

5

• Both quads and hamstrings guard
• Passive flexion and extension is difficult to
  perform
• Theoretical basis for implementation of in-hosp
  CPM
• CPM has not conclusively demonstrated to shorten
  the hosp stay or provide significantly increased
  ROM.
• Its value in early post op period is questionable
  in view of its cost

6

• Post op knee stiffness usually subsides within
  6-8 wks
• Knee ROM improves steadily thru the first 3
  months, then less rapid progress seen in next 9
  months
• If a limited or deteriorating ROM occurs,
  consider
• Infection
• Mechanical complications related to soft tissue
  or implant
• Impending arthrofibrosis
• RSD

7

• Late onset knee stiffness following a relatively
  symptom-free period may be suggestive of one of
  the following
• Infection
• Overuse synovitis or tendonitis (esp. in younger
  pt)
• Synovitis secondary to rheumatoid arthritis,
  particulate wear debris or recurrent hemarthrosis
• Implant loosening or breakage

8
Infection

• Early infection (within first 6 wks) is
  characterized by swelling, erythema, and
  generalized pain, with or without drainage.
• Late infection more easily recognized b/c it
  follows a relatively asymptomatic period
• Aspiration and culture required to distinguish an
  indolent infection from other cuases of synovitis

9
Mechanical Problems (Implant/Soft Tissue)

• B/c of the wide variety of available implant
  designs and rarity of severely stiff TKRs in
  published series, overall problem remains
  enigmatic
• Dorr found that pts who had obtained excellent
  clinical results following either PCL retaining
  or sacrificing designs continued to walk with a
  stiff knee gain 2 yrs post op
• Suggest that TKR rarely produce a completely
  normal gait

10

• The right balance b/n motion, strength, and
  stability is the surgical goal for a good fxnal
  outcome.
• Inadequate bone resection combined with
  persistent lig imbalance or tightness may result
  in knee stiffness
• If tightness is recognized, correct by either
  revising bone cuts, releasing ligaments, or a
  combination
• If flexion contracture, more distal femur removed
  or post capsular release

11

• Approach to bone resection in TKA is dependent on
  plan to preserve or sacrifice PCL
• If PCL preserved, femur is cut first to preserve
  the level of the jt line and more closely
  approximate the normal kinematics of the knee
• A potentially dangerous pitfall is reversing tilt
  of the tibia in the sagittal plane thus causing
  tightening of PCL in flexion if rollback mech
  fxns according to design

12

• Inadequate release of tight capsular and
  ligamentous structures is an important cause of
  stiff TKA
• Poor flexion and extension may result from
  inadequate release or recession of a tight PCL
• Medial collateral lig in varus deformities and
  LCL and iliotibial band in valgus deformities
  often require release to prevent asymmetric
  implant wear and promote optimal range of knee
  motion

13

• Patellofemoral dysfxn may cause pain that may
  promote stiffness b/c of disuse.
• Following patellar conditions should be
  considered when evaluating stiff TKA
• 1. patella not resurfaced
• 2. inadequate lateral release
• 3. Asymmetrical cutting of patella
• 4. Excessive elevation of jt line
• 5. Int rotation of fem comp
• 6. Formation of intra-art adhesions
• 7. Patella fx or comp loosening

14

• Excessive wear debri over a given period of time
  causes synovitis, pain, stiffness, and swelling
• Causative factors include
• Poor quality polyethylene
• High pt wt and activity level
• Failure to remove cement and bone debris from
  knee jt
• Implant design factors (contract stresses, poly
  distribution)

15
Patient Related factors

• Availability and efficiency of in-hosp P.T. has a
  significant impact on outcome of TKA
• With shorter hosp stays, an increasing reliance
  on outpt and home P.T. services
• An important factor is the pts willingness to
  undergo a rigorous rehab program
• Pt preferences, expectations, and satisfaction
  are important indicators as to the likelihood of
  obtaining good outcomes from surgery.

16

• Pre op education is an important tool for guiding
  the pt to understanding the goals and risks and
  benefits of surgery
• Educ process gives the surgeon an opportunity to
  recognize pts with unrealistic expectations or
  lack of motivation
• Host factors that promote arthrofibrosis about
  the knee jt are not well understood
• Inflammatory connective tissue dz have increased
  incidence of arthrofibrosis

17
Diagnostic Considerations

• Most important diagnostic tool in the eval of the
  stiff TKA is the physical exam
• 2 exams should be performed within the first 6
  wks to assure acceptable progress with ROM and
  fxnal status
• Plain x-rays should be ordered within the first 6
  wks and repeated if stiffness and pain increase.
• X-ray findings may include Inadequate bone
  resection, oversized fem component, evidence of
  lig imbalance resulting from asymmetric cement
  pressurization, or gross maltracking or
  subluxation of patella

18

• Bone scan is indicated in late cases of stiffness
• Less useful during early recovery period and
  throughout first year post op
• Cementless implants tend to increase bone scan
  activity up to 2 yrs
• Infection should be ruled out with an aspiration
  and culture of jt fluid
• Neg culture does not absolutely r/o infection
• If suspicion high, arthrotomy may be necessary to
  obtain tissue sample

19
Treatment Alternatives

• In a stiff, non infected, radiographically
  satisfactory TKA, most imp initial treatment is
  an adequately supervised course of sustained
  intensive P.T., lasting 3-6 months
• If, during the first 3 months, a plateau is
  reached, manipulation under anesthesia should be
  considered
• Fox Poss found a group of pts manipulated 2 wks
  post op and could not see any difference from
  control at 1 yr post op
• Pre op ROM is an imp predictor of post op motion

20

• Parsley and assoc reported 17 knees lt 75 deg
  flexion pre op, gained 16 deg post op
• 257 knees had gt 95 deg flexion and lost a mean of
  6 deg of flexion
• So knowledge of pre op flexion should assist the
  surgeon and pt with goals for motion post op
• If manipulation does not obtain acceptable ROM,
  an exploration and debridement may be performed,
  using open or arthroscopic techniques
• Arthroscopy good for localized tethering of
  patella or patellar clunk syndrome
• Results of arthroscopic tx of gen arthrofibrosis
  have not been as good

21
Revision Surgery

• Exchange of modular tibial polyethylene space in
  conjunction with capsular or ligamentous release
  may provide improvement of ROM
• Deformity should be completely corrected with a
  new trial spacer in place
• If correction not complete, revise tibial and/or
  femoral components after making new bone cuts.

22

• During revision for TKA stiffness, fully release
  all structures that may have contributed to
  condition including
• Quadriceps tendon and vastus intermedius adhesion
  to femur and suprapatella pouch
• Medial and lateral gutters
• Collateral ligaments
• Lateral patellar retinaculum

23
Prevention of Stiff TKA

• The most fundamental consideration for prevention
  of TKA complications in general is the selection
  of an implant and instrumentation sytem that is
  complex enough to allow flexibility, yet simple
  enough to minimize chance for technical error
• Based on a published track record of performance
  over 5-10 yrs
• Technical difficulty should be compatible with
  proficiency and experience of surgeon

24

• A design with less inherent stability or
  constraint will require more exacting bone cuts
  and ligament balancing to deliver an acceptable
  result
• Applies to many PCL retaining designs
• Cemented cruciate substituting designs have more
  inherent stability and will better tolerate the
  aggressive ligament releases required to correct
  severe varus or valgus deformities
• Elevation of jt line is also better tolerated in
  PCL substituting implants

25
Conclusion

• Knowledge of pt expectations, goals, and
  motivations is essential for early detection of
  potential problems with stiffness following TKA
• A poorly motivated pt with little or no pre op
  education combined with a short hosp stay and
  marginally delivered home or outpt P.T.
  constitutes a dangerous mix that may result in a
  less than optimal surgical result.
• More research is needed on this issue.