Use of Autologous Adipose-Derived Stromal Vascular Fraction to Treat Osteoarthritis of the Knee
Condition: Arthritis, Degenerative
MeSH terms: Osteoarthritis; Osteoarthritis, Knee
Study type: Interventional
Phase: Phase 1

Summary: 
      Autologous adipose-derived stromal vascular fraction (SVF) was used to treat 10
      osteoarthritic knees of grade II or III (K-L scale) under IRB-approved protocol in a
      feasibility and safety study. The adipose-derived SVF was obtained through disaggregation of
      lipoaspirate and resuspension of the SVF in 3 ml of Lactated Ringer's Solution, with a mean
      of 48 million nucleated SVF cells and a mean viability of 78%, injected per knee. Cell
      suspension was injected into the intra-articular space using ultrasound guidance. At 12 weeks
      post-op all 10 knees showed decreased pain and increased mobility, both statistically
      significant (α = .01). Nine of ten knees reported either maximum possible or very significant
      decrease in pain. No infections, acute pain flares, or other adverse events were reported.
      Patient ages ranged from 52 - 69 years with a mean of 59 years.
    

Detailed description: 
      Methods:

      Adipose Harvest. Using no oral or parenteral sedation, standard wetting solution (1 liter
      Lactated Ringer's, 50 milligrams of 1% lidocaine, and 1 cc of 1:1000 epinephrine) was infused
      through small incisions created with the tip of a #11 scalpel blade in the abdomen or flank
      using a standard multi-hole infusion cannula. A super-wet plus technique (2 volumes of
      wetting solution to 1 volume of proposed fat aspirate) was used to infuse the solution into
      the deep and superficial fat compartments. Twenty minutes was allowed for maximum
      vasoconstrictive effect of the epinephrine. Fat was harvested using standard
      Suctioned-Assisted Liposuction (SAL) method with a 3mm cannula at approximately .5 - .7
      atmosphere of vacuum, aspirating approximately 200-300 cc of lipoaspirate into a sterile
      tissue processing container (GID SVF-1, Lousiville, CO) for each knee to be treated.

      Adipose processing method. Lipoaspirate was harvested and processed all the way to the
      generation of the SVF within a single GID SVF-1 sterile disposable device. The GID SVF-1 unit
      contains the washing mechanism, the mesh filter, and the centrifuge capability in the same
      device. After harvest the lipoaspirate was washed three times with 37C Lactated Ringer's
      Solution with 20 mg Cipro and 5,000 units heparin per liter and the fluid portion removed
      using the mesh filter system, leaving dry adipose inside the canister. The canister was
      weighed to determine the amount of dry adipose available for further processing. The washed
      adipose was disaggregated using Type I collagenase (Worthington, Lakewood, NJ) at a
      concentration of 200 CDU/ml of total catalytic volume where total catalytic volume is the
      volume of the adipose tissue plus an equal volume of 37C Lactated Ringer's Solution. The
      collagenase was injected into the canister through a sterile .22 micron filter (Millex-MP,
      Millipore, Cork, Ireland). The device with adipose, buffer, and collagenase was then placed
      into an incubated shaker for 40 minutes at 38C at 150 RPM, see Figure 1. After disaggregation
      human albumin solution was added to achieve a concentration of 2.5% and stop any further
      collagenase activity. The device was then centrifuged at 800 g for 10 minutes. The
      supernatant, including all floating cells and debris and the aqueous phase, was removed using
      a port on the top of the device and discarded. The SVF pellet at the bottom was resuspended
      in 10 ml of sterile LR accessed via the central port on the device using a 14G 5.5 inch
      spinal needle (Abbocath-T, Hospira, Sligo, Ireland). A sample of 0.5 ml of the resuspension
      was collected in a 1.5 cc Eppendorf tube to be used for cell counting and assay. The
      resuspended SVF cells were concentrated into a 3 ml dose using a sterile 15 ml Falcon tube at
      400 g for 4 minutes.

      SVF counting method. The SVF cell count and viability was assessed using an ADAM MC image
      cytometry system (Bulldog Bio, Portsmouth, NH). The ADAM MC uses propidium iodide staining to
      count viable and non-viable nucleated cells. A 100 µL aliquot of the assay sample was diluted
      with a 1:5 ratio (1 part sample to 5 parts sterile LR) to adjust the sample within the
      operating limits of the ADAM MC. The differential stains were applied and aliquots loaded
      into the disposable cassette that is utilized with the ADAM device. The results from the ADAM
      counting device provide the concentration of SVF cells in the resuspension syringe and the
      percentage viability. The total volume of the resuspension in the syringe was multiplied by
      the concentration to give the total number of resuspended mononucleated cells (no adipose
      cells, no RBCs, and no fragments included in the counting process).

      Injection and image guidance method. The patient was placed in the supine position and the
      area over the lateral suprapatellar region of the knee was prepared in the usual sterile
      fashion using an iodine prep solution (1% Iodophor) followed by a 70% Isopropyl Alcohol
      solution. This location was used due to ease of access into the intra-articular space and to
      avoid injecting into the fat pad of the knee. No sedation or pain medication was administered
      to the patient. An ethylchloride topical anesthetic was sprayed on the lateral knee until the
      skin color changed to white. Lidocaine local anesthetic was injected using a 25 gauge needle
      to numb the skin and subcutaneous tissues. Using an M-Turbo Sonosite ultrasound system, the
      joint space was identified and under live ultrasound guidance the knee was aspirated using an
      18 gauge/1.5 inch needle, if fluids were available for aspiration. Then all of the 3 cc of
      buffered solution of SVF was slowly injected into the intra-articular space through the same
      18 gauge/1.5 inch needle. The needle was then be removed and direct pressure over the
      injection site will placed for approximately ten (10) seconds. Hemostasis after injection was
      confirmed, and then the injection site was cleaned with an alcohol wipe and covered with a
      sterile band-aid. The patient was given crutches and asked to be non-weight bearing on the
      injected knee for two (2) days. The patient was allowed to bend and flex the knee as long as
      non-weight bearing condition is maintained.

      Pain and mobility assessment methods. Assessment of knee pain was done using the PROMIS pain
      instruments, a validated pain scale system developed under funding by the NIH. PROMIS
      (Patient Reported Outcomes Measurement Information System) is a system for measures of
      patient reported health status for physical, mental, and social well-being, including three
      measurements of pain (www.nihpromis.org). The PROMIS Pain Intensity instrument (3a) assesses
      how much a person hurts. The PROMIS Pain Behavior instrument (Bank 1.0) measures behaviors
      that indicate to others that an individual is experiencing pain. The PROMIS Pain Interference
      instrument (Bank 1.0) measures the consequences of pain on relevant aspects of one's life.
      Patient responses are converted to numeric values in a validated scale. Responses to each
      question in a pain instrument range from 1 to 5 (1=not at all, 2=a little bit, 3=somewhat,
      4=quite a bit, 5=very much), and are summed over the number of questions in the bank to
      create a raw score. The raw score is converted to a standardized score using an iterative
      response method with a mean of 50 and SD of 10, based on a large sample of the general
      population of the United States. The validated PROMIS pain scales provide interval data and
      allows calculation of the mean and SD, and use of t-tests of significance. Data was recorded
      pre-operatively (time 0), and at follow-up points at 2 weeks, 4 weeks, 6 weeks, and 12 weeks.

      Additionally patients were asked to respond to a pain and mobility questionnaire with one
      question on pain and one question on mobility. The questionnaire asked the patient to compare
      their increase/decrease in pain and mobility relative to before surgery, using a ± 1-5 scale,
      see Figure 2. On this scale negative numbers correspond to decreasing pain/mobility, and
      positive numbers correspond to increasing pain/mobility. This questionnaire provides ordinal
      data and allows calculation of the median and significance using Wilcoxon Ranked Sums
      nonparametric testing.
    

Intervention name(s): intra-articular space injection of SVF
Intervention type(s): Other
Intervention description(s): intra-articular injection of autologous adipose SVF derived in the same surgical procedure
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Treatment