Musculoskeletal Week 11 - Knee Examinations

• Manual therapy techniques can be integrated into the intervention approach.
• Evaluation findings are analyzed to select appropriate manual therapy techniques.

Restoring Knee Flexion Mobility

• Tibiofemoral traction mobilization can restore knee flexion mobility.
  • The patient sits with the leg over the table while the therapist stabilizes the leg between their thighs.
  • An anterior, then posterior mobilization is performed at the proximal tibia to improve movement.
• Mobilization with movement is another method for restoring knee flexion mobility.
  • The patient is supine, and the knee is flexed to identify the pain range.
  • A belt on the ankle allows the patient to pull the leg into flexion, while the therapist applies posterior overpressure at the tibia.

Restoring Knee Extension Mobility

• The tibiofemoral anterior glide can restore knee extension mobility.
  • The patient is prone with a towel at the distal thigh to protect it and maintain a neutral hip angle.
  • The therapist applies an anterior force through the tibia, stabilizing just proximal to the ankle.
• Tibiofemoral extension overpressure mobilization.
  • A longitudinal force is applied at the tibial tuberosity by the movement arm.
  • Overpressure of extension is also applied, while the other hand stabilizes the knee proximal to the ankle.

Patellofemoral Joint Mobilization

• Medial, lateral, superior, and inferior patellar glides are performed.
• Superior/inferior patellar glides use the web space of the hand on the superior and inferior parts of the patella.
• Medial and lateral glides are performed with the patient in a side-lying position.
  • The lower leg will be used for a lateral glide.
  • The superior leg will be used for a medial glide.

Soft Tissue Mobilization

• Soft tissue mobilization techniques can be integrated into the intervention approach.
• Evaluation findings are analyzed to select appropriate soft tissue mobilization techniques.

Improving TFL/ITB Flexibility

• Tensor fasciae latae inhibition relaxation is used to improve TFL/ITB flexibility.
  • The patient inhales while flexing and abducting the leg, then exhales while extending and adducting the leg to relieve TFL tension.
• TFL/ITB Stretch in Standing involves standing with the opposite leg crossed in front and leaning away.
• Foam rolling the TFL/ITB involves direct application to the TFL muscle, moving down the ITB band to find and pause at tension areas.

Improving Gastrocnemius Flexibility

• A gastrocnemius stretch is performed in standing.
• The knee is bent during the stretch to bias the soleus.
• Foam rolling the gastrocnemius can also be used.

Rectus Femoris Stretch

• A belt is applied proximal to the ankle, and the patient passively pulls the leg into more flexion.

Knee Therapeutic Exercise

• Therapeutic exercises are identified and applied based on knee impairments.

Flexibility Training Guidelines

• Perform 2-4 repetitions per muscle group.
• Stretching should be done 2-3 days per week.
• Static stretches should be held at a point of mild discomfort for 10-30 seconds.
• Each muscle group should be stretched for at least 60 seconds.

Therapeutic Exercises Include

• Mobility exercises.
• Motor coordination exercises.
• Functional movement exercises.
• Tendon reloading exercises.

ACL Injury Prevention

• Understand the mechanism of injury for ACL injuries.
• Determine the indications for prevention programs for ACL injuries.
• Implement an ACL injury prevention program.

ACL Injury Facts

• ACL injury is the most common ligamentous injury of the knee.
• Injuries are noncontact.
  • Occur during deceleration.
  • Cutting.
  • Landing movements.
• Mechanism: knee valgus, tibial rotation, and decreased knee flexion.
• Individuals in high-level cutting and pivoting sports, many under 25 years of age, are more likely to experience this type of injury.
• 74.2-83% of athletes return to sport, with only 50% at their prior level.
• There is a 4-15% chance of recurrent ligamentous disruption.
• There is a 5-34% chance of injury to the contralateral limb post-surgery.
• Females are more likely to experience than males.
• There is an increased risk of developing knee OA after ACL injury.

Nonsurgical Approach

• A higher success rate is possible for individuals who avoid or mitigate high-risk activities.
• Nonoperative return to high-level activities based on self-selection has ranged from 23% to 42%.
• 79% of copers who had perturbation and agility training and strengthening returned to previous activity levels.
• 12-32% of individuals with ACL deficiency have quadriceps strength deficits for 1 or 2 years after injury.
• Younger patients are more likely to experience poor outcomes with a nonsurgical approach.
• High Tegner Scale scores indicate a poor nonsurgical prognosis.

Pre-Screening for Surgical Candidate Criteria

• Level I or II athlete or work (> 50 hrs/year of cutting, pivoting, or jumping).
• No concomitant knee injuries.
• No repairable meniscus on MRI.
• Zero-to-trace knee effusion.
• Full knee ROM.
• Normal gait.
• Greater than 70% isometric quadriceps strength on bilateral comparison.
• No pain with hopping on the injured limb.

Screening Test Battery

• Includes four single-legged hop tests.
  • Single hop for distance.
  • Crossover hop for distance.
  • Triple hop for distance.
  • 6-minute timed hop are compared bilaterally.
• The number of giving way episodes reported with activities of daily living (ADLs) since the time of injury.
• Knee Outcome Survey-Activities of Daily Living Scale (KOS-ADLS) score should be greater than or equal to 80%.
• Global Rating Scale of Perceived Knee Function score should be more than or equal to 60%.
• Patients must meet the pre-screening criteria to be considered a possible coper and then go through the screening test
• Individuals must have less than one giving away episode with activities of daily living.
• The single leg 6-minute timed hop score of greater than or equal to 80% with bilateral comparison.
• They are automatically placed in the potential non-coper category if unable to meet any one of the test battery criteria.

Screening for a Coper

• Four single-legged hop tests (single hop for distance, crossover hop for distance, triple hop for distance, 6-minute timed hop) that are compared bilaterally.
• The number of giving way episodes reported with activities of daily living since the time of injury- less than or equal to one giving way episode.
• Knee Outcome Survey-Activities of Daily Living Scale – score greater than or equal to 80%.
• Global Rating Scale of Perceived Knee Function (GRS) - greater than or equal to 60%.
• Rate current knee function on a scale of 0-100.
  • 0 is the inability to perform any activity, and 100 is being back to the level of function before the injury.
• KOS and GRS should be completed following the hop testing.
  • Allows patients to self-evaluate their knees during physically challenging tasks.
  • Leads to much more accurate readings on the self-report surveys.

Management for Nonsurgical Approach

• RICE.
• Gait training with crutches.
• Education on long-term outcomes.
• Limit participation in athletic activities.

Strength Training

• Focus on quadriceps femoris and hamstrings.
• Both open and closed kinetic chain exercises can be used.
• Low-impact aerobic conditioning should be used until knee stability improves.

Neuromuscular Training Techniques

• Perturbation-based balance training.
• Research shows that rehab for a partially torn acute ACL improves stability within three months.
• Therapy lasts up to 12 months if the knee still has some instability after 3 months.

Perturbation Training

• Early Phase Goals:
  • Expose athlete to perturbations in all directions.
  • Elicit an appropriate muscular response to applied perturbations.
  • Minimize verbal cues.
• Middle Phase Goals:
  • Add light sport-specific activity during perturbation techniques.
  • Improve athlete accuracy in matching muscle responses to perturbation intensity, direction, and speed.
• Late Phase Goals:
  • Increase difficulty of perturbations by using sport-specific stances.
  • Obtain accurate, selective muscular responses to perturbations in any direction and of any intensity, magnitude, or speed.

Prevention Strategies

• Aim to increase proprioception and neuromuscular control through balance, perturbation, plyometric, proximal control, and strengthening activities.
• External cueing can facilitate implicit learning.
• Video or real-time feedback may be beneficial

Coaching Education

• Functional knee braces are typically more advantageous than not wearing an ACL brace in an ACL-deficient population.

Post-Operative Management

• Understanding the indications for knee surgical procedures is key.
• Post-operative rehabilitation should be progressed within rehabilitation guidelines, considering healing time frames and patient response.
• Describe typical outcomes for knee surgical procedures.

Surgical Procedures

• Includes total knee arthroplasty, ACL repair, meniscectomy, and meniscal repair.

Total Knee Arthroplasty

• Metal implants that are customized for each patient’s joint nuances are placed on the articulating surface of the knee joint and secured with medical cement.
• A plastic space may be put in the joint to allow the surfaces to move smoothly against each other.
• This usually occurs after total Knee OA.

Total Knee Replacement Outcomes

• About 78% of TKAs last 20 years, and > 90% of TKAs last for 10 years.

Total Knee Replacement Rehabilitation

• Preoperative:
  • Normal ROM.
  • Quadriceps strengthening, which can include NMES.
  • Patient and caregiver education.
• Phase 1 (Protected knee movement):
  • Protect the injury site.
  • Reduce pain and swelling.
  • Assistive device training.
  • Increase knee ROM.
• Phase 2 (Progress knee motion and strengthening):
  • Avoid running, jumping, or twisting motions.
  • Increase knee ROM and strength.
• Phase 3 (Functional Sensorimotor Training, last 6+ weeks):
  • Progress exercise to include levels of weightbearing and motion.
  • Include single leg exercises, e.g., balancing or squats.
  • HEP (home exercise program).

Clinical Practice Guidelines Intervention Recommendations

• Rating scale is 1 to 4 (4 is 100% definitive).
• Pre-operative exercise program = 3 out of 4.
• Motor function training = 4 out of 4.
• Interventions should address patient deficits or impairments.
• Outcome measures used should be geared towards this.

ACL Repair/Reconstruction

• A torn ACL is removed and replaced with a section of tendon (graft).
• The goal of surgical management is to restore anterior stability of the tibiofemoral joint.
• Surgeons prioritize graft fixation strength and material integrity, along with reproduction of the anatomical footprint.
• Allograft - Graft material comes from outside the body.
• Autograft - Graft material comes from the patient.
  • Usually, a hamstring autograft is used, but the quad patellar bone or patella tendon are options too.
• Patients with hamstring autografts demonstrate both knee flexor and extensor weakness as far as nine months past surgery.
• Patients with patella tendon graft only demonstrate knee extensor weakness.
• Males with patella tendon grafts, females with any type of graft, and adolescents with any graft demonstrate persistent quadricep weakness up to a year post-surgery.
• Patient-reported outcomes for hamstring autographs are superior to those of other grafts.

Management for ACL Injury

• Pre-Optive Phase:
  • Reduce pain and swelling and work on full extension.
  • Extension deficit is associated with increased risk of extension deficits post-ACL reconstruction.
  • Improve quadriceps strength.
  • Crutch training.
  • Prep of postop exercises and expectations.
• Phase 1 (weeks 0-4):
  • Protected motion phase.
  • Early mobilization to decrease adverse changes in articular cartilage, prevention of scar tissue that could limit the soft tissue and joint range of motion and trying to reduce pain.
  • Straighten the affected knee to 0 degrees of knee extension.
  • Able to bend the knee to 120 degrees.
  • Improve walking technique and activate the quadriceps.
• Phase 2 (weeks 4-8):
  • Progressive loading/strengthening phase.
  • Includes resistance exercises where there's no pain with exercise and little to no swelling.
  • Work towards performing home and work exercises without issues.
• Phase 3 (8-12 weeks):
  • Challenge positional sense in space and improve the ability to perform functional activities, progressing exercises.
  • Start sports/recreational activity.
  • Athletes should be able to return to high-demand activities to prevent re-injury of the affected knee or injury to the unaffected knee.
  • Athlete should be able to perform basic sports-related activities without restrictions.
• Phase 4 (16+ Weeks):
  • Return to sport and improve tolerance for functional/recreational activities.
  • Test the jumping ability of both legs.
  • HEP to prevent future injuries.
  • Athlete should be able to perform physically demanding work without issues.
  • Athlete should reach their desired level of sport performance and be able to perform a home exercise program properly before the last session of rehab.
• Prehab, combined with post-operative rehab protocols, has improved patient-reported knee function at 12 weeks postoperatively and up to two years after ACL reconstruction.

ACL Repair Outcomes

• Younger age (< 20-25 years), higher activity level, and allograft use increase the risk of reinjury.
• The incidence of reinjury in those participating in high-risk cutting and pivoting sports and under the age of 25 is 23%.
• Patient reports and function improve from early on after surgery up to 6 years after surgery.
• Readiness to return to sport occurs at ~ 4-6 months, with full return-to-sport activities at ~ 6-12 months.
• The incidence of ROM deficits following ACL reconstruction is between 2% and 11%.
• Loss of flexion and extension range of motion is correlated to lower quadriceps strength.
• This loss can increase forces to the patellofemoral joint and alter gait mechanics, putting the patient at risk for developing knee OA.
• Quadriceps strength deficits improve over time.
• ACLR restores the mechanical properties of the ACL but not the proprioceptive properties, so upregulation of associated knee, hip, and ankle control must be regained.

Return to Sport Post ACL Repair

• Requires at least a 90% limb symmetry index, with 100% required for pivoting/contacts sports.
• Returning to sport prior to 9 months after repair has shown an increased risk of ACL injury, with a 51% decrease for each month following 6 months since surgery.

Return-to-Sport Tests

• Single, Crossover, and Triple Hop tests for Distance require > 90% contralateral limb symmetry or > 100% in pivoting sports.
• Standard benchmark is 80-100% of patient's height
• 6-meter hop test for time also requires the same contralateral symmetry

Wilk et al 8-Step Sequence includes

• Blazepod lateral slide test, 4 corners test, Right versus Left Reactive Test, Reactive 10-yard T shuttle run test, Reactive 10-yeard L run test, Reactive single-limb hop for distance test, Reactive single-limb crossover hop for distance test, Reactive single-limb alternating crossover hop for distance test,

Meniscectomy Definition

• Removal of frayed edges of the meniscus by clipping them away.

Management for Meniscectomy

• Phase 1 (Immediate post-op day 0-7):
  • Swelling management and ROM/Mobility.
  • Criteria to progress = 0-90 degrees; strengthen with straight leg raises.
  • Goals = Restore ROM and re-establish quadriceps activation; reach 0 degrees extension; Patient education.
• Phase 2 (Immediate post-op day 8- Week 2):
  • ROM/mobility looking for pain-free movement.
  • Gradual return to functional activities while monitoring symptom response, increasing strength and endurance.
  • Single leg standing steady and unsteady surface for balance and proprioception.
• Phase 3 (Late post-op weeks 2-8):
  • Maintain full ROM
  • Cardio
  • Gymnasium machines for Strengthening.
  • Emphasis on muscles above knee for Proximal stability.
  • Perturbations, Y balance, star excursion for balance/proprioception.
• Phase 4 (Return to sport 9-12 weeks post):
  • Multi-plane sport-specific plyometrics and agility.
  • Hard cutting and pivoting depending on individual’s goals.

Goals for Meniscectomy

• No pain and swelling with exercise, proper movement patterns, and a return to all necessary and desired functional activities, work duties, and athletic activities.

Functional Assessment Milestones

• Quadriceps index at least 80%, hamstring glute max and glute Medius index needs to be 80%, degree of a leg hop test minimum 75 degrees compared to the contralateral side.

Meniscectomy Outcomes

• 15% conversation rate at 20 years from arthroscopic meniscectomy to total knee replacement.
• Female sex, older age, lateral meniscectomy, malalignment, preoperative osteoarthritis, and advanced chondral lesion found to be relate to subsequent total knee replacement.

Meniscal Repair

• Occurs when tear causes the edges of the meniscus to become frayed, leading to popping or clicking in the knee.
• The goal is to re-establish integrity of the meniscus edges at the site of the tear.

Management for Meniscal Repair

• Vertical, longitudinal tears:
  • First 2 weeks:
    • Immediate partial weight-bearing and quadriceps setting exercises with NMES.
  • 3-4 weeks:
    • Full weight-bearing and 0-90 degrees knee flexion ROM and OKC non-resistive quadriceps and hip exercises.
  • 5-6 weeks:
    • OKC resistive quadriceps exercises, non-resistive hamstring exercises.
  • 12 weeks:
    • Progressive strengthening exercises and squatting to 90 degrees.
  • Return to sport at 3-4 months.
• Radial and complex tears:
  • First 2 weeks:
    • No weight-bearing and quadriceps setting exercises with NMES.
  • 3-4 weeks:
    • Partial weight-bearing 0-90 knee flexion ROM, and OKC non-resistive quadriceps and hip exercises.
  • 5-6 weeks:
    • Full weight-bearing 0-90 degrees knee flexion ROM, and OKC resistive quadriceps exercises, non-resistive hamstring exercises.
  • 12 weeks:
    • Full knee flexion ROM and squatting to 60 degrees knee flexion.
  • Return to sport at 6 months.

Key Subjective and Functional Milestones

• Achieve quadriceps neuromuscular control and decrease pain and edema.
• Controlled weight-bearing with good quadriceps control, increased hip and quadriceps strength.
• Normalized gait, improved hamstring-quadriceps co-contraction at the knee, increased hamstring strength.
• Restore normal activities of daily living, begin running when 60% quadriceps strength symmetry is achieved.
• No knee pain, full knee ROM, and at least 90% quadriceps strength symmetry for return to sports.

Meniscal Repair Outcomes

• The failure rates are 33% in those > 30 years old and 12% in those < 30 years old
• Failure is higher in those with an earlier return to sport.

Patellar Taping Indications

• Increases patellar mobility and decrease the patient’s pain
• McConnell’s test, step down, and resisted knee extension test