Sources and References

Protein

1. Schricker T, Lattermann R. Perioperative catabolism. Can J Anaesth 2015;62:182–93
   A review of how surgery switches the body to breaking down its own protein; a healthy adult can lose one to two kilograms of muscle after a major elective operation.
2. Ferrando AA et al. Pre- and post-surgical nutrition for preservation of muscle mass, strength, and functionality following orthopedic surgery. Nutrients 2021;13:1675
   After knee replacement, thigh muscle can shrink by up to 18% within six weeks, most of it in the first two — and what to eat to limit that.
3. Dreyer HC et al. Essential amino acid supplementation in patients following total knee arthroplasty. J Clin Invest 2013;123:4654–66
   Randomized trial: 20 g of essential amino acids twice a day cut thigh-muscle loss from 14% to 3% at two weeks and from 18% to 6% at six weeks, with better mobility.
4. Dreyer HC et al. Essential amino acid supplementation mitigates muscle atrophy after total knee arthroplasty: a randomized, double-blind, placebo-controlled trial. JBJS Open Access 2018;3:e0006
   Confirmatory randomized trial: less thigh-muscle loss with supplementation, and no safety problems.
5. Ueyama H et al. Perioperative essential amino acid supplementation suppresses rectus femoris muscle atrophy and accelerates early functional recovery following total knee arthroplasty. Bone Joint J 2020;102-B(6 Suppl A):10–18
   Randomized trial: 9 g a day of amino acids from one week before to two weeks after surgery preserved thigh muscle and sped the return to daily activities.
6. Khani A et al. Peri-operative protein or amino acid supplementation for total joint arthroplasty: a systematic review and meta-analysis. J Orthop Surg Res 2025
   Review of 19 studies and 903 patients: protein or amino-acid supplementation around joint replacement reduces thigh-muscle loss.
7. Tischler EH et al. Hypoalbuminemia associated perioperative mortality, reoperation, and readmission rates among total joint arthroplasty procedures: a systematic review and meta-analysis. Eur J Orthop Surg Traumatol 2025
   Review of 21 studies and more than 600,000 patients: low blood protein before surgery roughly doubles the chance of a repeat operation or readmission.
8. Arapovic AE et al. Nutritional considerations in hip and knee arthroplasty: a critical analysis of current evidence. JBJS Rev 2024;12(8)
   A critical review of nutrition around hip and knee replacement recommending 1.2 to 1.9 g of protein per kilogram of body weight each day, especially for people with low muscle mass.
9. Coletta G et al. Prevalence of sarcopenia indicators and sub-optimal protein intake among elective total joint replacement patients. Appl Physiol Nutr Metab 2023;48:498–506
   Three-quarters of people awaiting joint replacement ate less than 1.2 g of protein per kilogram per day; those who ate more protein were stronger.
10. Weimann A et al. ESPEN practical guideline: clinical nutrition in surgery. Clin Nutr 2021;40:4745–61
    The European surgical-nutrition guideline: surgical patients need about 1.5 g of protein per kilogram per day, and poor nutrition raises the risk of complications.

Weight-loss medications and protein

1. Korus S et al. Dietary intake patterns and nutritional adequacy among adults with overweight or obesity treated with GLP-1 or dual GIP/GLP-1 receptor agonists. J Transl Med 2026;24:532
   387 adults taking once-weekly GLP-1 or GIP/GLP-1 medications kept food diaries: average intake was 753 calories and 33 g of protein a day, and fewer than one in ten met the protein recommendation.
2. Neeland IJ et al. Changes in lean body mass with glucagon-like peptide-1-based therapies and mitigation strategies. Diabetes Obes Metab 2024
   A review of what these medications do to muscle: lean tissue makes up a substantial share of the weight lost, and protein plus resistance exercise protects it.
3. Wilding JPH et al. Once-weekly semaglutide in adults with overweight or obesity (STEP 1). N Engl J Med 2021;384:989–1002
   The main semaglutide trial; its body-composition substudy found lean mass fell 9.7% alongside fat.
4. Look M et al. Body composition changes during weight reduction with tirzepatide in the SURMOUNT-1 study. Diabetes Obes Metab 2025
   Body-composition substudy of tirzepatide: about a quarter of the weight lost was lean mass.

Diosmin

The two-month course before and after surgery is Dr. Olsen's protocol; the trials below studied the two weeks after surgery.

1. Wang Q et al. Efficacy of diosmin in reducing lower-extremity swelling and pain after total knee arthroplasty: a randomized, controlled multicenter trial. J Bone Joint Surg Am 2024;106:492–500
   Randomized trial of 330 patients at 13 hospitals: diosmin for 14 days after knee replacement reduced calf, thigh and knee swelling and pain with movement, with no increase in complications.
2. Girgin AB, Duman E. Is a combination of diosmin and hesperidin effective on swelling, pain, and range of motion after total knee arthroplasty? J Arthroplasty 2026;41:2043–50
   Randomized trial of 176 patients: diosmin with hesperidin for 14 days after knee replacement gave less swelling, less pain, and better knee bend at two weeks (105° versus 91°).
3. Lyseng-Williamson KA, Perry CM. Micronised purified flavonoid fraction: a review of its use in chronic venous insufficiency, venous ulcers and haemorrhoids. Drugs 2003;63:71–100
   How diosmin and hesperidin work on vein tone and capillary leakage, and their safety record: side effects no more frequent than placebo.

Step limits

The weekly limits are Dr. Olsen's protocol, from his experience with his own patients. The link between early swelling and a slower recovery is documented below.

1. Holm B et al. Loss of knee-extension strength is related to knee swelling after total knee arthroplasty. Arch Phys Med Rehabil 2010;91:1770–6
   Early after knee replacement, the more the knee swells, the more thigh strength is lost.
2. Pua YH. The time course of knee swelling post total knee arthroplasty and its associations with quadriceps strength and gait speed. J Arthroplasty 2015;30:1215–9
   Knee swelling peaks early after replacement; more swelling goes with weaker thigh muscles and slower walking.
3. Loyd BJ et al. The relationship between lower extremity swelling, quadriceps strength, and functional performance following total knee arthroplasty. Knee 2019;26:382–91
   Greater early swelling predicted weaker thigh muscles and slower function at two and six weeks; limiting peak swelling may speed recovery.
4. Yang L et al. Factors associated with early swelling after total knee arthroplasty and poor venous return. BMC Musculoskelet Disord 2026;27
   In the first days after knee replacement, longer time walking and standing tended toward more swelling; the authors recommend paced walking and rest with the leg up.
5. Bourne RB et al. Patient satisfaction after total knee arthroplasty: who is satisfied and who is not? Clin Orthop Relat Res 2010;468:57–63
   Of 1,703 knee-replacement patients, about one in five was not satisfied with the result.
6. Gunaratne R et al. Patient dissatisfaction following total knee arthroplasty: a systematic review of the literature. J Arthroplasty 2017;32:3854–60
   A systematic review of why patients are dissatisfied after knee replacement.

Strengthening exercises

Waiting four weeks before strength work is Dr. Olsen's protocol. The link between knee swelling and lost motion and strength is documented below.

1. Holm B et al. Loss of knee-extension strength is related to knee swelling after total knee arthroplasty. Arch Phys Med Rehabil 2010;91:1770–6
   Early after knee replacement, the more the knee swells, the more thigh strength is lost.
2. Loyd BJ et al. The relationship between lower extremity swelling, quadriceps strength, and functional performance following total knee arthroplasty. Knee 2019;26:382–91
   Greater early swelling predicted weaker thigh muscles and slower function at two and six weeks; limiting peak swelling may speed recovery.

Driving after knee replacement

Six weeks for a right knee is Dr. Olsen's protocol; it is at the cautious end of what the studies below found.

1. Marques C et al. What is the evidence on which physicians can rely to advise patients when they may resume driving after TKA? A systematic literature review. J Funct Morphol Kinesiol 2018;3:8
   Review of driving studies: braking recovered on average 44 days after a right knee replacement (the authors recommend six weeks) and 20 days after a left (three weeks).
2. Giannoudis VP et al. Doctor when can I drive? Braking response after knee arthroplasty: a systematic review & meta-analysis of brake reaction time. Knee 2021;30:214–40
   Pooled analysis of 12 studies: braking movement time was slower at two to four weeks and back to normal by six weeks.
3. DiSilvestro KJ et al. When can I drive after orthopaedic surgery? A systematic review. Clin Orthop Relat Res 2016;474:2557–70
   Review of 48 studies across orthopaedic surgery: right knee about four weeks, left knee up to three, right hip about four weeks — and no driving while taking opioid pain medication.
4. Marques CJ et al. Does the brake response time of the right leg change after left total knee arthroplasty? A prospective study. Knee 2008;15:295–8
   After a left knee replacement, the right leg's braking was normal at ten days, so an automatic car can be driven sooner.
5. Na A, Richburg K, Gugala Z. Clinical considerations for return to driving a car following a total knee or hip arthroplasty: a systematic review. Biomed Res Int 2020;2020:8921892
   Review of 23 studies on driving after knee and hip replacement; it is safe to drive only once you are off narcotic pain medication.

Driving after hip replacement

The three- and four-week figures, and the age cut-off, are Dr. Olsen's protocol. The studies below measured how quickly braking recovers.

1. Hernandez VH et al. When is it safe for patients to drive after right total hip arthroplasty? J Arthroplasty 2015;30:627–30
   After a right hip replacement, 87% of patients were braking normally by two weeks and all by four.
2. Richards JT et al. Rapid return to braking after anterior and posterior approach total hip arthroplasty. JAAOS Glob Res Rev 2024;8(4)
   Braking returned to normal by two weeks after hip replacement through either the anterior or the posterior approach.
3. Patel PV et al. Doctor when can I drive? A systematic review and meta-analysis of return to driving after total hip arthroplasty. Hip Int 2023;33:17–27
   Pooled analysis of 14 studies: braking is clearly better than before surgery from six weeks; the authors advise judging each patient individually.
4. DiSilvestro KJ et al. When can I drive after orthopaedic surgery? A systematic review. Clin Orthop Relat Res 2016;474:2557–70
   Review of 48 studies across orthopaedic surgery: right knee about four weeks, left knee up to three, right hip about four weeks — and no driving while taking opioid pain medication.

Ice

The 30-minutes-on, 30-off routine and the ice-machine advice are Dr. Olsen's protocol.

1. Aggarwal A et al. Cryotherapy following total knee replacement. Cochrane Database Syst Rev 2025;(10):CD007911
   Cochrane review: cold therapy modestly reduces pain and swelling after knee replacement.
2. Keskin M et al. Frostbite injury due to improper usage of an ice pack. Ann Plast Surg 2005;55:437–8
   A case of frostbite from an ice pack left on too long — the reason for the 30-minutes-off rule.

Showering

1. Toon CD et al. Early versus delayed post-operative bathing or showering to prevent wound complications. Cochrane Database Syst Rev 2015;(7):CD010075
   Cochrane review: showering early after surgery did not increase wound infections.
2. Yu AL et al. Wound hygiene practices after total knee arthroplasty: does it matter? J Arthroplasty 2016;31:2256–9
   Knee-replacement patients who showered from day two had no more wound problems than those who waited two weeks, and preferred it.
3. Jans Ø et al. Orthostatic intolerance during early mobilization after fast-track hip arthroplasty. Br J Anaesth 2012;108:436–43
   In the first day after hip replacement, four in ten patients felt faint on standing.
4. Folly de Campos T et al. Orthostatic intolerance-type events following hip and knee arthroplasty: a systematic review and meta-analysis. J Bone Joint Surg Am 2023;105:239–49
   Review: feeling faint or fainting on standing is common in the first days after hip and knee replacement.

Creams and ointments on the wound

Leaving the wound alone is Dr. Olsen's protocol.

1. Baumann LS, Spencer J. The effects of topical vitamin E on the cosmetic appearance of scars. Dermatol Surg 1999;25:311–5
   Vitamin E on healing scars did not improve their appearance and caused a skin reaction in about a third of people.

Bone growing into the implant

The three-month pause from stop-and-start sports is Dr. Olsen's protocol.

1. Pilliar RM, Lee JM, Maniatopoulos C. Observations on the effect of movement on bone ingrowth into porous-surfaced implants. Clin Orthop Relat Res 1986;(208):108–13
   Bone grows into a porous implant only when the implant is nearly still; too much movement produces scar tissue instead.
2. van der Water L et al. Migration patterns of uncemented femoral stems in hip replacement: a systematic review and meta-analysis of clinical RSA cohort studies. Acta Orthop 2026;97:247–54
   Review of stem-migration studies: uncemented hip stems settle during the first three months, then hold steady.

Walker, cane or crutches

Three to four weeks with a walking aid is Dr. Olsen's protocol.

1. Farmer KW et al. Trochanteric bursitis after total hip arthroplasty: incidence and evaluation of response to treatment. J Arthroplasty 2010;25:208–12
   About one hip-replacement patient in twenty develops bursitis over the outside of the hip; most settle with treatment.

Pain shooting past the knee

1. Brown MD et al. Differential diagnosis of hip disease versus spine disease. Clin Orthop Relat Res 2004;(419):280–4
   How doctors tell hip pain from spine pain: a limp, groin pain and a stiff hip point to the hip; pain that travels down past the knee usually points to the spine.

Dr. Olsen's protocol

From Dr. Olsen's Quiet Knee Protocol — his standing instructions for his own patients.

Answers about dressings, the OnQ pump, who to call and when, taking your regular medications, and how to reach the office are Dr. Olsen's instructions for his own patients. They come from his practice, not from a published study, and the app says so under each one.