Joint Arthroplasty

purpose of arthroplasty

pain relief, restore ROM, improve function and quality of life, avoid secondary sequelae

indications for arthroplasty

joint degeneration, trauma, pain, deformity, dysfunction

considerations for arthroplasty

>60 years of age (15-20+ life span of prothesis) → younger with severe dysfunction

bone integrity → osteoporosis? no surgery

contraindications for arthroplasty

infection → clean viable bone required for healing

age →

arthroplasty guidelines

implants must be: durable and low coefficient of friction

materials: metal (convex) + plastic (concave)

interface between articulating partners must be stable

interface between bone and prosthesis must be secure and durable

types of arthroplasty

osteotomy

surface replacement arthroplasty

hemiarthroplasty

unicompartmental

total joint arthroplasty (TKA, THA)

osteotomy

surgically induced fracture and re-alignment → redistribute load beaing

younger pts to delay arthroplasty

limited WB post-operatively

surface replacement arthroplasty

advantage - bone preservation

may not be possible with poor bone quality

hemiarthroplasty

partial joint replacement → only one partner in joint replaced with prosthesis

most common: hemiarthroplasty of hip (femoral head/neck replaced after fracture)

unicompartmental

one compartment of knee - usually medial

results similar to TKA → 90% survivorship at 10yrs

less invasive surgery BUT just delays eventual TKA

THA procedure

ligaments and muscles divided

hip dislocated

femoral head excised

acetabulum reamed out

acetabular component inserted

femoral canal reamed out

femoral stem inserted

component fixation utilized

cemented - components glued in place (bone cement penetrates porous bone) → allows for early WB

non-cemented

porous prosthesis

gradual increase in WB over six weeks → allows bone in growth + better for younger, more active

hybrid

component cemented, non-cemented - acetabulum usually non-cemented

if anticipating another surgery, this can be detrimental

cement can be detrimental

posterolateral THA approach

through gluteus maximus - hip dislocated posteriorly (prone → flexion, adduction, internal rotation

anterolateral THA approach

between TFL and gluteus medius - hip dislocated anteriorly (supine → extension, external rotation)

posterolateral approach risks

tying shoes, rolling in bed, sitting with legs crossed, sitting low, turning with walker

hip precautions posterolateral approach

flexion beyond 90 degrees

internal rotation

adduction beyond midline

posterolateral approach has a

higher postsurgical dislocation rate

hip precations: anterolateral approach

extension

external rotation

adduction beyond midline

TKA variation - PCL retention

more natural stability retained

more complex surgery

TKA variation - PCL sacrifice

stability depends more on prosthesis

posterior stabilizer component may be used

TKA/THA complications

infection, integumentary concerns, excessive bleeding, leg length inequality, DVT, PE, MI, sciatic/femoral nerve palsy (THA), post-op dislocation (THA)

long term THA/TKA complications

prosthesis loosening

prosthesis failure

arthrofibrosis (stiff joint)

WB status for TKA and THA are

WBAT

TKA precautions

no restrictions

pre-operative considerations for TKA: exercise

associated with better post-op functional outcome, no specific regimens identified, address flexibility and strength based on individual, pre-op status associated with post-op status

pre-operative considerations for TKA: education

expectation during hospitalization

factors influencing discharge

post-op rehab program

transfer techniques

assistive devices

acute care orthro: early mobility

start within 24hrs

bed mobility, transfers, WB/weight shifting, gait and stair training with AD

acute care orthro: early ROM

0-90 degrees knee flexion as soon as possible

stretching, patellar mobz, repetitive movement

CPM

positioning for ROM

we want ___________ recruitment in acute care ortho

early quad

post arthroplasty rehab: authorized activities

bowling

dance

gardening

golf

stationary biking

swimming

walking

post arthroplasty rehab: activities with experience

caneoing

doubles tennis

hiking

road bike

rowing

skiing

working out (progressive)

post arthroplasty rehab: unauthorized activities

basketball

bouldering

football

gymnastics

jogging

racquetball

volleyball

goal of ROM for post arthroplasty rehab

0-120 degrees → anything beyond is great

post arthroplasty rehab - e-stim

high intensity NMES

early - 5-7x a day, for at least 3 weeks

max tolerable intensity