MEDICAL POLICY

POLICY
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DESCRIPTION
SCOPE
BENEFIT APPLICATION
RATIONALE
REFERENCES
CODING
APPENDIX
HISTORY

Knee Arthroplasty in Adults

Number 7.01.550

Effective Date February 15, 2014

Revision Date(s) N/A

Replaces N/A

Policy

Knee Arthroplasty may be considered medically necessary for degenerative joint disease when certain modified criteria are met. (see Policy Guidelines)

Knee Arthroplasty may be considered medically necessary for other indications only when applicable MCG™ criteria are met. (see Knee Arthroplasty (ORG: S-700 [ISC])

NOTE: Adult is defined as “individuals at or over 18 years of age”.

Related Policies

7.01.15

Meniscal Allograft and Other Meniscus Implants

Policy Guidelines

MCG™ criteria are used as a tool to guide medical necessity determinations and utilization management decisions, per licensed agreement.

Degenerative Joint Disease

Please use the following modified criteria MCG™ criteria.

  • Treatment of degenerative joint disease is indicated by ALL of the following:
  • Treatment is needed because 1 or more of the following
  • Disabling pain
  • Functional disability
  • NOTE: (An example of a tool for assisting in assessing pain or functional disability in the provider’s office, is the KOOS http://www.koos.nu/ , see Appendix).
  • Presence of significant radiographic findings, as evidenced by a Kellgren-Lawrence (KL) grade of 3 or 4. (see below for KL grading scale)
  • For a KL score of 3, the documentation must include:
  • Evidence of a trial of anti-inflammatory medication and/or analgesics, AND
  • Physical therapy exercises which increase flexibility and muscle strength (at least 6 visits over 12 weeks), AND
  • Reasonable restriction of activities.
  • For a KL score of 4, the medical documentation must include:
  • Evidence of a trial of anti-inflammatory medication and/or analgesics

All Other Knee Arthroplasty Indications

  • For all other knee arthroplasty indications, please refer to the MCG™ criteria: Knee Arthroplasty (ORG: S-700 [ISC]).

Kellgren-Lawrence Grading Scale

  • Grade 1: Doubtful narrowing of joint space and possible osteophytic lipping
  • Grade 2: Definite osteophytes, definite narrowing of joint space
  • Grade 3: Moderate multiple osteophytes, definite narrowing of joints space, some sclerosis and possible deformity of bone contour
  • Grade 4: Large osteophytes, marked narrowing of joint space, severe sclerosis and definite deformity of bone contour

Note: The MCG™ manuals are proprietary and cannot be published and/or distributed. However, on an individual member basis, the Company can share a copy of the specific criteria used to make a utilization management decision. If you would like a copy of these criteria, you may request a copy of the criteria by calling the Customer Service number on the member’s health plan card.

The Plan reserves the right to review and modify MCG™ or Customized Guidelines at any time.

Description

Modern total knee arthroplasty consists of resection of the diseased articular surfaces of the knee, followed by resurfacing with metal and polyethylene prosthetic components. For the properly selected patient, the procedure results in significant pain relief, as well as improved function and quality of life. Despite the potential benefits of total knee arthroplasty, it is an elective procedure and should only be considered after extensive discussion of the risks, benefits, and alternatives.(2)

The main indication for total knee arthroplasty is for the relief of pain associated with arthritis of the knee in patients who have failed nonoperative treatments. Correction of deformity and restoration of function should be considered secondary outcomes of the surgery and should not be considered the primary indication. The prosthetic joint has a finite lifetime, and factors upon which the durability of the prosthesis depends include patient age, underlying disease, and presence of obesity, as well as prosthesis and surgical factors.(2)

Patients with osteoarthritis limited to just one part of the knee may be candidates for unicompartmental knee replacement (also called a “partial” knee replacement). Unicompartmental (medial, lateral, or patellofemoral) is an option for a small percentage of patients with osteoarthritis of the knee. In a unicompartmental knee replacement, only the damaged compartment is replaced with metal and plastic. (3)

Scope

Medical policies are systematically developed guidelines that serve as a resource for Company staff when determining coverage for specific medical procedures, drugs or devices. Coverage for medical services is subject to the limits and conditions of the member benefit plan. Members and their providers should consult the member benefit booklet or contact a customer service representative to determine whether there are any benefit limitations applicable to this service or supply.

Benefit Application

N/A

Rationale

Guidelines recommendations from the American Academy of Orthopaedic Surgeons (AAOS) clinical practice guideline, “Treatment of Osteoarthritis of the Knee”. 2nd edition, May 2013(4)

Recommendation 1

  • We recommend that patients with symptomatic osteoarthritis of the knee participate in self-management programs, strengthening, low-impact aerobic exercises, and neuromuscular education; and engage in physical activity consistent with national guidelines.
  • Strength of Recommendation: Strong
  • Description: A strong recommendation means that the benefits of the recommended approach clearly exceed the potential harm and/or that the quality of the supporting evidence is high.

Recommendation 2

  • We suggest weight loss for patients with symptomatic osteoarthritis of the knee and a BMI > 25.
  • Strength of Recommendation: Moderate
  • Description: A moderate recommendation means the benefits exceed the potential harm (or that the potential harm clearly exceeds the benefits in the case of a negative recommendation), but the quality/applicability of the supporting evidence is not as strong.

Recommendation 3

  • We are unable to recommend for or against the use of a valgus directing force brace (medial compartment unloader) for patients with symptomatic osteoarthritis of the knee.
  • Strength of Recommendation: Inconclusive
  • Description: An inconclusive recommendation means that there is a lack of compelling evidence that has resulted in an unclear balance between benefits and potential harm.

Recommendation 7A

  • We recommend nonsteroidal anti-inflammatory drugs (NSAIDs; oral or topical) or Tramadol for patients with symptomatic osteoarthritis of the knee.
  • Strength of Recommendation: Strong
  • Description: A strong recommendation means that the benefits of the recommended approach clearly exceed the potential harm and/or that the quality of the supporting evidence is high.

Recommendation 7B

  • We are unable to recommend for or against the use of acetaminophen, opioids, or pain patches for patients with symptomatic osteoarthritis of the knee.
  • Strength of Recommendation: Inconclusive
  • Description: An inconclusive recommendation means that there is a lack of compelling evidence that has resulted in an unclear balance between benefits and potential harm.

Recommendation 8

  • We are unable to recommend for or against the use of intraarticular (IA) corticosteroids for patients with symptomatic osteoarthritis of the knee.
  • Strength of Recommendation: Inconclusive
  • Description: An inconclusive recommendation means that there is a lack of compelling evidence that has resulted in an unclear balance between benefits and potential harm.

Recommendation 9

  • We cannot recommend using hyaluronic acid for patients with symptomatic osteoarthritis of the knee.
  • Strength of Recommendation: Strong
  • Description: A strong recommendation means that the benefits of the recommended approach clearly exceed the potential harm and/or that the quality of the supporting evidence is high.

Excellent long-term outcomes can be achieved with contemporary methods of ligament reconstruction and open reduction and internal fixation for injuries around the knee; nevertheless, posttraumatic arthritis frequently develops. Reconstruction options for symptomatic posttraumatic knee arthritis include osteotomy, arthrodesis, and arthroplasty. Surgical challenges include the presence of extensive (often broken) hardware, scarring, stiffness, bony defects, compromised soft tissues, and malalignment. Patient age and activity and the anatomic location and extent of damage to the articular surface must be taken into account when determining the surgical treatment plan. For younger patients, osteotomy, allograft transplantation, or arthrodesis of the knee is considered, whereas older, low-demand patients are usually treated with arthroplasty. Attention to specific technical details and careful surgical technique are necessary to achieve a successful result. Functional improvement is usually seen following arthroplasty and, sometimes, arthrodesis. However, complications are common, and outcomes following arthroplasty are generally inferior to those reported for other diagnoses.(5)

Knee-replacement surgery is frequently done and highly successful. It relieves pain and improves knee function in people with advanced arthritis of the joint. The most common indication for the procedure is osteoarthritis. The authors reviewed the epidemiology of and risk factors for knee replacement. Because replacement is increasingly considered for patients younger than 55 years, improved decision making about whether a patient should undergo the procedure is needed. They discuss assessment of surgery outcomes based on data for revision surgery from national joint-replacement registries and on patient-reported outcome measures. Widespread surveillance of existing implants is urgently needed alongside the carefully monitored introduction of new implant designs. Developments for the future are improved delivery of care and training for surgeons and clinical teams. In an increasingly ageing society, the demand for knee-replacement surgery will probably rise further, and they predict future trends. They also emphasized the need for new strategies to treat early-stage osteoarthritis, which will ultimately reduce the demand for joint-replacement surgery.(6)

The purpose of this study was to evaluate the independent contributions of surgeon procedure volume, hospital procedure volume, and standardization of care on short-term postoperative outcomes and resource utilization in lower-extremity total joint arthroplasty. Methods: An analysis of 182,146 consecutive patients who underwent primary total joint arthroplasty was performed with use of data entered into the Perspective database by 3421 physicians from 312 hospitals over a two-year period. Adherence to evidence-based processes of care was defined by administration of appropriate perioperative antibiotic prophylaxis, beta-blockade, and venous thromboembolism prophylaxis. Patient outcomes included mortality, length of hospital stay, discharge disposition, surgical complications, readmissions, and reoperations within the first thirty days after discharge. Hierarchical models were used to estimate the effects of hospital and surgeon procedure volume and process standardization on individual and combined surgical outcomes and length of stay. Results: After adjustment in multivariate models, higher surgeon volume was associated with lower risk of complications, lower rates of readmission and reoperation, shorter length of hospital stay, and higher likelihood of being discharged home. Higher hospital volume was associated with lower risk of mortality, lower risk of readmission, and higher likelihood of being discharged home. The impact of process standardization was substantial; maximizing adherence to evidence-based processes of care resulted in improved clinical outcomes and shorter length of hospital stay, independent of hospital or surgeon procedure volume. Conclusions: Although surgeon and hospital procedure volumes are unquestionably correlated with patient outcomes in total joint arthroplasty, process standardization is also strongly associated with improved quality and efficiency of care. The exact relationship between individual processes of care and patient outcomes has not been established; however, our findings suggest that process standardization could help providers optimize quality and efficiency in total joint arthroplasty, independent of hospital or surgeon volume.(7)

In 2009, Osteoarthritis Research Society International (OARSI) evaluated new research evidence. Sixty-four systematic reviews, 266 randomized controlled trials (RCTs) and 21 new economic evaluations (EEs) were published between 2006 and 2009. Of 51 treatment modalities, new data on efficacy have been published for more than half (26/39, 67%) of those for which research evidence was available in 2006. Among non-pharmacological therapies, the effect sizes (ES) for pain relief were unchanged for self-management, education, exercise and acupuncture. However, with new evidence the ES for pain relief for weight reduction reached statistical significance, increasing from 0.13 [95% confidence interval (CI) 0.12, 0.36] in 2006 to 0.20 (95% CI: 0.00, 0.39) in 2009. By contrast, the effect sizes for electromagnetic therapy which was large in 2006 (ES¼0.77, 95% CI: 0.36, 1.17) was no longer significant (ES¼0.16, 95% CI: 0.08, 0.39). Among pharmacological therapies, the cumulative evidence for the benefits and harms of oral and topical non-steroidal anti-inflammatory drugs, diacerhein and intra-articular (IA) corticosteroid was not greatly changed. The ES for pain relief with acetaminophen diminished numerically, but not significantly, from 0.21 (0.02, 0.41) to 0.14 (0.05, 0.22) and was no longer significant when analysis was restricted to high quality trials (ES¼0.10, 95% CI: 0.0, 0.23). New evidence for increased risks of hospitalization due to perforation, peptic ulceration and bleeding with acetaminophen >3 g/day have been published (hazard ratio ¼1.20, 95% CI: 1.03, 1.40). ES for pain relief from IA hyaluronic acid, glucosamine sulphate, chondroitin sulphate and avocado soybean unsponifiables also diminished and there was greater heterogeneity of outcomes and more evidence of publication bias. Among surgical treatments further negative RCTs of lavage/debridement were published and the pooled results demonstrated that benefits from this modality of therapy were no greater than those obtained from placebo.(8)

There is broad consensus that good outcome measures are needed to distinguish interventions that are effective from those that are not. This task requires standardized, patient-centered measures that can be administered at a low cost. A questionnaire was developed to assess short- and long-term patient-relevant outcomes following knee injury, based on the WOMAC Osteoarthritis Index, a literature review, an expert panel, and a pilot study. The Knee Injury and Osteoarthritis outcome Scores (KOOS) is self-administered and assesses five outcomes: Pain, symptoms, activities of daily living, sport and recreation function, and knee-related quality of life. In this clinical study, the KOOS proved reliable, responsive to surgery and physical therapy, and valid for patients undergoing anterior cruciate ligament reconstruction. The KOOS meets basic criteria of outcome measures and can be used to evaluate the course of knee injury and treatment outcome.(9)

References

  1. MCG™ - 17th Edition (formerly Milliman Care Guidelines®): Inpatient and Surgical Care, ORG: S-700 (ISC). Available online at: http://careweb.careguidelines.com/ed17/. Last accessed on October 24, 2013.
  2. Martin G, Thornhill T, Katz J. Total Knee Arthroplasty. Available on-line. UpToDate, Furst, D (Ed), UpToDate®, Waltham, MA, 2013.
  3. American Academy of Orthopaedic Surgeons. Unicompartmental knee replacement, patient information. 2013, Available online at: http://orthoinfo.aaos.org/topic.cfm?topic=A00585 Last accessed October 24, 2013.
  4. American Academy of Orthopaedic Surgeons. Treatment of osteoarthritis of the knee. 2013, 2nd edition. Available online at: http://www.aaos.org/research/guidelines/GuidelineOAKnee.asp Last accessed October 24, 2013.
  5. Bedi A, Haidukewych GJ. Management of the posttraumatic arthritic knee. Journal of the American Academy of Orthopedic Surgeons 2009;17(2):88-101.
  6. Carr AJ, et al. Knee replacement. Lancet 2012;379(9823):1331-40.
  7. Bozic KJ, Maselli J, Pekow PS, Lindenauer PK, Vail TP, Auerbach AD. The influence of procedure volumes and standardization of care on quality and efficiency in total joint replacement surgery. Journal of Bone and Joint Surgery. American Volume 2010;92(16):2643-52.
  8. Zhang W, Nuki G, Moskowtiz RW, et al. OARSI recommendations for the management of hip and knee osteoarthritis: part III: Changes in evidence following systematic cumulative update of research published through January 2009. Osteoarthritis Cartilage 2010; 18:476. Available online at: http://www.oarsi.org/pdfs/part_III_changes_in_evidence2010.pdf Last accessed October 24, 2013.
  9. Roos EM, Roos HP, Lohmander LS, Ekdahl C, Beynnon BD. Knee Injury and Osteoarthritis Outcome Score (KOOS)-development of a self-administered outcome measure. J Orthop Sports Phys Ther 1998; Aug 28(2): 88-96 http://www.koos.nu/. Last accessed October 24, 2013.
  10. Reviewed by board certified orthopedic specialists, October 2013.

Coding

Codes

Number

Description

CPT

27445

Arthroplasty, knee, hinge prosthesis (e.g., Walldius type)

 

27446

Arthroplasty, knee condyle and plateau; medial OR lateral compartment

 

27447

Arthroplasty, knee, condyle and plateau; medial AND lateral compartments with or without patella resurfacing (total knee arthroplasty)

 

27486

Revision of total knee arthroplasty, with or without allograft; 1 component

 

27487

Revision of total knee arthroplasty, with or without allograft; femoral and entire tibial component

ICD-9 Diagnosis

170.7

Malignant neoplasm of bone and articular cartilage; Long bones of lower limb

 

170.8

Malignant neoplasm of bone and articular cartilage; Short bones of lower limb

 

716.16

Traumatic arthropathy, lower leg

 

996.43

Broken prosthetic joint implant

 

996.44

Peri-prosthetic fracture around prosthetic joint

ICD-9 Procedure

81.54

Total knee replacement

 

81.55

Revision of knee replacement, not otherwise specified

Appendix

The following is taken from the KOOS website and is offered as a tool in determining functional disability. To access more detailed information, visit the KOOS website at: http://www.koos.nu/.

Knee Injury and Osteoarthritis Outcome Score (KOOS)

KOOS Knee Survey

Today’s date: _____/______/______ Date of birth: _____/______/______

Name: ____________________________________________________

INSTRUCTIONS: This survey asks for your view about your knee. This information will help us keep track of how you feel about your knee and how well you are able to perform your usual activities.

Answer every question by ticking the appropriate box, only one box for each question. If you are unsure about how to answer a question, please give the best answer you can.

Symptoms

These questions should be answered thinking of your knee symptoms during the last week.

S1. Do you have swelling in your knee?

¨ Never ¨ Rarely ¨ Sometimes ¨ Often ¨ Always

S2. Do you feel grinding; hear clicking or any other type of noise when your knee moves?

¨ Never ¨ Rarely ¨ Sometimes ¨ Often ¨ Always

S3. Does your knee catch or hang up when moving?

¨ Never ¨ Rarely ¨ Sometimes ¨ Often ¨ Always

S4. Can you straighten your knee fully?

¨ Never ¨ Rarely ¨ Sometimes ¨ Often ¨ Always

S5. Can you bend your knee fully?

¨ Never ¨ Rarely ¨ Sometimes ¨ Often ¨ Always

Stiffness

The following questions concern the amount of joint stiffness you have experienced during the last week in your knee. Stiffness is a sensation of restriction or slowness in the ease with which you move your knee joint.

S6. How severe is your knee joint stiffness after first wakening in the morning?

¨ Never ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

S7. How severe is your knee stiffness after sitting, lying or resting later in the day?

¨ Never ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

Pain

P1. How often do you experience knee pain?

¨ Never ¨ Monthly ¨ Weekly ¨ Daily ¨ Always

What amount of knee pain have you experience the last week during the following activities?

P2. Twisting/pivoting on your knee

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P3. Straightening knee fully

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P4. Bending knee fully

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P5. Walking on a flat surface

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P6. Going up or down stairs

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P7. At night while in bed

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P8. Sitting or lying

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

P9. Standing upright

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

Functional, Daily Living

The following questions concern your physical function. By this we mean your ability to move around and to look after yourself. For each of the following activities, please indicate the degree of difficulty you have experienced in the last week due to your knee.

A1. Descending stairs

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A2. Ascending stairs

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

For each of the following activities, please indicate the degree of difficulty you have experienced in the last week due to your knee.

A3. Rising from sitting

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A4. Standing

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A5. Bending to floor/pick up an object

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A6. Walking on a flat surface

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A7. Getting in/out of car

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A8. Going shopping

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A9. Putting on socks/stockings

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A10. Rising from bed

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A11. Taking off socks/stocking

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A12. Lying in bed (turning over, maintaining knee position)

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A13. Getting in/out of bath

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A14. Sitting

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A15. Getting on/off toilet

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

For each of the following activities, please indicate the degree of difficulty you have experienced in the last week due to your knee.

A16. Heavy domestic duties (moving heavy boxes, scrubbing floors, etc.)

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

A17. Light domestic duties (cooking, dusting, etc.)

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

Function, Sports and Recreational Activities

The following questions concern your physical function when being active on a higher level. The questions should be answered thinking of what degree of difficulty you have experienced during the last week due to your knee.

SP1. Squatting

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

SP2. Running

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

SP3. Jumping

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

SP4. Twisting/pivoting on your injured knee

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

SP5. Kneeling

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

Quality of Life

Q1. How often are you aware of your knee problem?

¨ Never ¨ Monthly ¨ Weekly ¨ Daily ¨ Constantly

Q2. Have you modified your life style to avoid potentially damaging activities to your knee?

¨ Not at all ¨ Mildly ¨ Moderately ¨ Severely ¨ Totally

Q3. How much are you troubled with lack of confidence in your knee?

¨ Not at all ¨ Mildly ¨ Moderately ¨ Severely ¨ Extremely

Q4. In general, how much difficulty do you have with your knee?

¨ None ¨ Mild ¨ Moderate ¨ Severe ¨ Extreme

Thank you very much for completing all the questions in this questionnaire.

KOOS Scoring 2012

A change in how to manage missing items was introduced in 2012. Previously, 2 missing items were allowed in each subscale. From 2012, at least 50% of the items should be responded to. This change is reflected in the updated Excel scoring file formulae available from http://www.koos.nu/. The differences in subscale level are outlined in the following table:

 

Number of items needed for calculation of subscale score (2012 rule for missing items)

Number of items needed for calculation of subscale (1998 rule for missing items)

Pain

5

7

Symptoms

4

5

ADL

9

15

Sports/Recreation

3

3

QOL

2

2

KOOS Scoring Instructions

Assign the following scores to the boxes:

¨ None (0) ¨ Mild (1) ¨ Moderate (2) ¨ Severe (3) ¨ Extreme (4)

Each subscale is calculated independently. Calculate the man score of the individual items of each subscale and divide by 4 (the highest possible score for a single answer option). Traditionally in orthopedics, 100 indicates no problems and 0 indicates extreme problems. The normalized score is transformed to meet this standard.

Missing Data: If a mark is placed outside a box, the closest box is chosen. If two boxes are marked, tht which indicated the more severe problem is chose. As long as 50% of the subscale items are answered for each subscale, a mean score can be calculated. If more than 50% of the subscale items are omitted, the response is considered invalid and no subscale score should be calculated. For the subscale Pain, this means that 5 items must be answered; for Symptoms, 4 items; for ADL, 9 items; for Sports/Recreation, 3 items; and for QOL, 2 items must be answered in order to calculate a subscale score. Subscale scores are independent and can be reported for any number of individual subscales, i.e., if a particular subscale is not considered valid Ifor example, the subscale Sport/Rec 2 weeks after total knee replacement), the results from the other subscale can be reported at this time-point.

KOOS Excel Scoring Files

Excel spreadsheets with formulae to calculate the five subscale scores are available from http://www.koos.nu/. If, for any reason, you prefer to use your own spreadsheets, the Excel formulae are given below.

Excel Formulation: When the raw data have been entered in the order the items occur in the KOOS questionnaires available from koos.nu, these Excel formulations can be copied and pasted directly into an English version of an Excel spreadsheet to automatically calculate the five subscore scales. Please note that it has been assumed that the items in the subscale symptoms appear first in the questionnaire.

KOOS Pain: =100-AVERAGE(I2:Q2)/4*100

KOOS Symptoms: =100-AVERAGE(B2:H2)/4*100

KOOS ADL: =100-AVERAGE(R2:AH2)/4*100

KOOS Sport/Rec: =100-AVERAGE(AI2:AM2)/4*100

KOOS QOL: =100-AVERAGE(AN2:AQ2)/4*100

KOOS Manual Score Calculation

The slightly updated version of the formulae (presented above and used from August 2012 in the spreadsheets available from http://www.koos.nu/) does not need any manual imputation: Apply the mean of the observed items within the subscale (e.g. KOOS Pain), divide by 4, and multiply by 100; when this number is then subtracted from 100, you have the KOOS subscale estimate for that particular cross-sectional assessment of the individual patient. For manual calculations, please use the formulae provided below for each subscale:

  1. PAIN 100 – (Mean Score (P1 – P9)x100) / 4 = KOOS Pain
  2. SYMPTOMS 100 – (Mean Score (S1 – S7)x100) / 4 = KOOS Symptoms
  3. ADL 100 – (Mean Score (A1 – A17)x100) / 4 = KOOS ADL
  4. SPORT/REC 100 – (Mean Score (SP1 – SP5)x100) / 4 = KOOS Sport/Rec
  5. QOL 100 – (Mean Score (Q1 – Q4)x100) / 4= KOOS QOL

WOMAC - How to score from the KOOS

Assign scores from 0 to 4 to the boxes as shown above. To get original WOMAC Scores, sum the item scores for each subscale. If you prefer percentage scores in accordance with the KOOS, use the formula provided below to convert the original WOMAC scores.

Transformed scale = 100 – (actual raw score x 100) / maximum score

WOMAC subscores

Original score = sum of the following items

Maximum score

Pain

P5 – P9

20

Stiffness

S6 – S7

8

Function

A1 – A17

68

KOOS Profile

To visualize differences in the five different KOOS subscores and change between different administrations of the KOOS (e.g. pre-treatment to post-treatment), KOOS Profiles can be plotted. The example from Nilsdotter et al. [17] shows KOOS profiles prior to and at three time points following total knee replacement (TKR).

History

Date

Reason

11/11/13

New Policy. Added to Surgery section. Considered medically necessary when criteria are met. Approved with 90-day hold for provider notification; this policy is effective February 15, 2014.

03/31/14

Coding update. ICD-9 Diagnosis codes 170.7, 170.8, 716.16, 996.43, and 996.44 added to policy.


Disclaimer: This medical policy is a guide in evaluating the medical necessity of a particular service or treatment. The Company adopts policies after careful review of published peer-reviewed scientific literature, national guidelines and local standards of practice. Since medical technology is constantly changing, the Company reserves the right to review and update policies as appropriate. Member contracts differ in their benefits. Always consult the member benefit booklet or contact a member service representative to determine coverage for a specific medical service or supply. CPT codes, descriptions and materials are copyrighted by the American Medical Association (AMA).
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