Arthroplasty and Knee Arthroplasty Notes

Arthroplasty

  • Arthroplasty is a surgical procedure used to restore the function of a joint, which can be achieved by resurfacing the bones.
  • An artificial joint, known as a prosthesis, may be used.
  • Common joint replacements include:
    • Hip and knee replacements (most common).
    • Ankle, wrist, shoulder, and elbow.

Knee Arthroplasty

  • Knee replacement, also known as knee arthroplasty or total knee replacement, is a surgical procedure to resurface a knee damaged by arthritis.
  • Metal and plastic parts are used to cap the ends of the bones that form the knee joint, along with the kneecap.
  • Indications:
    • Osteoarthritis (OA)
    • Rheumatoid arthritis (RA)
    • Avascular necrosis (AVN) or osteonecrosis (ON)
    • Congenital dislocation of the hip joint (CDH)
    • Hip dysplasia
    • Acetabular dysplasia (shallow hip socket)
    • Frozen shoulder, loose shoulder.
    • Traumatized and malaligned joint.
    • Joint stiffness.
  • Contraindications:
    • Acute/chronic local or systemic infection
    • Severe diseases of muscles, nerves, or blood vessels
    • Poor muscle or ligament tissues
    • Any disease that might result from the operation and affect the function and success of implants.
    • Allergy to implants, particularly to metals
    • Renal dysfunction.
    • Local bone tumor or bone cyst
    • Pregnancy.

Physiotherapy Rehabilitation After Knee Arthroplasty

Pre-surgical Physiotherapy

  • Post-surgical rehabilitation exercises may be taught before surgery to enhance post-surgical recovery.
  • Pre-surgical training programs may be used to optimize the functional status of patients to improve post-surgical recovery.
  • Pre-surgical training programs should focus on postural control, functional lower limb exercises, and strengthening exercises for bilateral lower extremities.
  • Evidence supporting the efficacy of pre-surgical physiotherapy on patient outcome scores, lower limb strength, pain, range of movement, or hospital length of stay following total knee arthroplasty is lacking.

Post-surgical Physiotherapy

  • Physiotherapy interventions are effective tools for improving a patient's physical function, range of motion, and pain in the short term after total knee replacement.
  • Long-term benefits and cost-effectiveness of physiotherapy interventions after a total knee replacement need further study.
Subjective Assessment
  • Assessment should include, but is not limited to:
    • Operative and post-operative complications, if any
    • History of knee and other musculoskeletal complaints, if any
    • Past medical history and relevant comorbidities
    • Social factors and home set-up
    • Progress of in-home exercises post-TKA surgery
    • Pain and other symptoms/discomfort (e.g., numbness, swelling)
    • Expectations from surgery and rehabilitation
    • Specific functional goals
Objective Assessment
  • Assessment should include, but is not limited to:
    • Observation of surgical wound or scar
    • Check for signs of infection:
      • Redness, discharge (pus/odor), adhesions of the skin, abnormal warmth and swelling, expanding redness beyond the edges of the surgical incision, fever, or chills.
      • Suspicion of infection warrants medical referral.
    • Knee swelling (circumference measurement)
    • Vital signs and relevant laboratory findings (as relevant/in the acute setting)
    • Check for deep vein thrombosis (DVT):
      • Homan’s sign test
      • Signs and symptoms of chest pain, shortness of breath, calf redness or discoloration, deep calf heat, pain, or tenderness
      • Suspicion of DVT warrants urgent medical referral
    • Palpation:
      • For increased warmth and swelling
      • For muscle activation (e.g., quadriceps; vastus medialis oblique) and hypertonia (e.g., hip adductors)
    • Lower limb range of motion:
      • Active and passive knee range of motion in supine or semi-reclined position
    • Lower limb muscle activation and strength
    • Gait:
      • Timed up and go test (TUG) or 10-meter walk test may be used (depending on individuals’ ability and tolerance)
      • Assess for guarding in knee flexion, avoidance to weight bear on the operative leg, antalgic patterns, etc.
Post-surgical Physiotherapy Treatment Strategies & Goals
Phase I: Up to 2-3 weeks post-surgery
  • Patient education: pain science, pain management, the importance of home exercises, setting rehabilitation goals and expectations
  • Achieve active and passive knee flexion to 90 degrees, and full knee extension
  • Keep passive knee flexion range of motion testing to less than 90 degrees in the first 2 weeks to protect surgical incision and respect tissue healing
  • Aim to achieve minimal pain and swelling
  • Achieve full weight bearing
  • Aim for independence in mobility and activities of daily living
  • During the early phase of rehabilitation, it is important to establish a therapeutic alliance and provide education on pain management strategies. Pain education may include appropriate usage of pain medication, cryotherapy and elevation of the operated limb. There is evidence that cryotherapy improves knee range of motion and pain in the short-term. Icing after exercise may be helpful, but low quality evidence makes specific recommendations for the use of cryotherapy difficult. Patients should be informed to avoid resting with a pillow under the knee as this may lead to contractures.
  • It is important to review the patient’s home exercise program during the first physiotherapy session as home exercises are a critical component of recovery. Post-surgical exercises given by the surgeon and inpatient physiotherapist should be reviewed. In the early phase, patients can be taught to use the stairs with their nonoperated leg leading on the ascent, and their operated leg leading on the descent.
  • COMMON BED AND CHAIR EXERCISES
    • Ankle plantarflexion/dorsiflexion
    • Inner range quadriceps strengthening using a pillow or rolled towel behind the knee
    • Isometric knee extension in the outer range
    • Knee and hip flexion/extension
    • Straight leg raises
    • Isometric buttock contraction
    • Hip abduction/adduction
    • Bridging
Phase II: 4-6 weeks post-surgery
  • Aim to have no quadriceps lag, with good, voluntary quadriceps muscle control
  • Achieve 105 degrees active knee flexion range of motion
  • Achieve full knee extension
  • Aim for minimal to no pain and swelling
  • Physiotherapy sessions may be scheduled one to two times weekly, This frequency may increase or decrease depending on an individual's progress. Achieving full knee extension is essential for functional tasks such as walking and stair climbing. Knee flexion range of motion is required for comfortable walking (65 degrees), stair climbing (85 degrees), sitting and standing (95 degrees). In this phase, tissue mobilisation techniques may be used to improve scar mobility.
Phase III: 6-8 weeks post-surgery
  • Strengthening exercises to ensure hypertrophy beyond neural adaptation
  • Lower limb functional exercises
  • Balance and proprioception training
  • Balance exercises may include single leg balancing, stepping over objects, lateral step- ups, and standing on uneven surfaces. Post-surgical balance and proprioceptive training
  • that involves single limb standing may begin when adequate knee control is achieved on the operated limb, which typically occurs around 8 weeks post-TKA.
  • Individualised rehabilitation programmes that include strengthening and intensive functional exercises, given through landbased or aquatic programmes, may be progressed as clinical and strength milestones are met. Owing to the highly individualised characteristics of these exercises, supervision by a trained physiotherapist is beneficial.
Phase IV: 8-12 weeks, up to 1 year post-surgery
  • Aim for independent exercise in the community setting
  • Continue regular exercise involving strengthening, balance and proprioception training
  • Incorporate strategies for behaviour change to increase overall physical activity
Discharge Criteria
  • Discharge planning should be individualised, and criteria may include:
    • Achieving a minimum 110 degrees active knee flexion and full knee extension
    • Achieving ambulation goals
    • Achieving compliance and competency with a home exercise programme
    • Commitment to an independent exercise program for 6-12 months post-operatively should be recommended
    • Exercise programme should include strength training 2-3 times/ week
Complications Following TKA surgery
  • Infection
  • Nerve damage
  • Bone fracture (intra-operative or post-operative)
  • Persistent / chronic pain
  • Increased Falls risk
  • Deep vein thrombosis (DVT)