Regional Interdependence: Effects on the Tibiofemoral (Knee) Joint

by Dr. Bruce Buckman PT, DPT, ART

Regional interdependence is the concept that “seemingly unrelated impairments in remote anatomical regions of the body may contribute to and be associated with a patient’s primary report of symptoms.” The majority of the literature surrounding regional interdependence in the lower extremity has been focused on low back pain, which has been positively correlated to hip osteoarthritis, decreased strength, neuromuscular control, range of motion, and mobility of the lower extremity. Relationships between the foot, ankle, and the low back have also been reported. The examples of regional interdependence are endless, some more obscure than others, but let’s break down a simple one that may not be all that “seemingly unrelated.” This example is one that I see in many, if not all of my elementary school and high school athletes.

Regional Interdependence and Tibiofemoral (Knee) Pain

The knee, for many young athletes, becomes a problem in sports that involve running, jumping, lunging, and lateral change of direction. Trying to think of a sport that doesn’t involve these movements? Keep thinking… Keep thinking… Exactly. The knee often gets a bad reputation and is the source of a lot of unnecessary force during these aforementioned activities, while in reality your hips and feet are most likely significant contributing factors to your knee pain. So how can your foot and hip be contributing to your knee pain?

The Foot’s Role In Knee Pain

Pes planus, or simply put, having flat feet (Figure 1) is a term that describes an observation in static postures. When moving, your foot may fall into pronation. Pronation is actually a normal part of the gait cycle. In fact, foot pronation is necessary to soften the blow and absorb contact from ground reaction forces when walking.

Figure 1. Foot Pronation

“Over/excessive pronation” is the correctly used terminology that describes the medial longitudinal arch (Figure 2) collapsing towards the ground. Now, how does over-pronation tie into the concept of regional interdependence? Simply put…it starts from the ground up. When the foot makes contact with the ground and overly pronates, increased stress is placed on the medial (inside) aspect of the lower extremity. This medial stress travels up the kinetic chain to the next closest joint (the knee) causing a valgus moment as well as medial tibial rotation (Figure 3). In static standing, valgus knee stress is not a huge issue, but place the knee under significant load with activities such as running, jumping, lunging, and lateral change of direction activities and this stress can cause dysfunction leading to muscle strains, ligament sprains, and capsular restrictions. Know someone who has had an ACL/PCL injury? Consider this… The ACL and the PCL twist around one another forming an “X” pattern. Both the ACL and PCL become taught with medial tibial rotation and subsequent lateral (outside) femoral rotation (Figure 3). Continuing on, the femur (leg bone above the knee) becomes adducted and medially rotated placing stress on the acetabular femoral joint leading to more potential muscle strains and hip labrum pathology. This stress finally makes its way to the sacroiliac joint and lumbar spine.

Figure 2. Medial Longitudinal Arch







Figure 3. Kinetic Chain Breakdown







Figure 4. ACL/PCL








The Hip’s Role In Knee Pain

Aside from anatomical variables such as femoral anteversion (twisting in of the thigh bone at the femoral head) and femoral retroversion, (twisting out of the thigh bone at the femoral head) most of the dysfunction that occurs at the hip is muscular when relating the hip to knee pain. The hip abductors (gluteus medius and tensor fascia latae) along with the gluteus maximus and external rotators pull the hip away from the body in an open kinetic chain position (feet off the floor) such as in sitting. However, when in standing, the activation of these muscles pull the knee outward, away from midline and prevent dynamic genu valgus (Figure 5). In single limb stance, the lack of activation of these muscles causes Trendelenburg’s hip drop, which has been associated with Patellofemoral Pain Syndrome. In fact, subjects with Patellofemoral Pain Syndrome (PFPS) also display 18% less hip abduction and 17% less hip external rotation strength. Muscles such as the Vastus Medialis Oblique (VMO) often take blame for being weak, or under activated in patients with PFPS; however, research has denied this muscle’s ability to be isolated with EMG studies. While the VMO anatomically assists in the “tracking” of the patella, a more regional approach involving strengthening the hip musculature may influence knee mechanics to a greater degree. The biceps femoris (hamstring), rectus femoris (quadriceps) and Illiotibial band (abductor) influence the knee in a more direct way by crossing both the hip and knee joint, directly affecting the knee during functional movement patterns. What does this all do to the knee? Besides the rotary forces I explained above, this valgus stress collapses the lateral knee capsule and puts a significant amount of tensile strength on the medial knee joint deeming it susceptible for ligamentous/cartilaginous (MCL, ACL, PCL, meniscus), tendinous (pes anserine) and capsule injury.

Figure 5. Dynamic Genu Valgus


Using regional interdependence, clinicians can effectively evaluate and treat the body as whole rather than specific joints, which may lead to incorrect diagnoses of associated musculoskeletal disorders. Joints above and below your primary impairment may be contributing factors, and if not addressed, could lead to the re-occurrence of chronic injury. Call us at The Spine and Health Center of Montvale at 201-746-6577 for a physical therapy regional interdependence evaluation today!



Sueki et al. A regional interdependence model of musculoskeletal dysfunction: research, mechanisms, and clinical implications. J Man Manip Ther. 2013 May; 21(2): 90–102.

Nakasagawa et al. Trunk, pelvis, hip and knee kinematics, hip strength and gluteal muscle activation during a single-leg squat in males and females with and without patellofemoral pain syndrome. Journal of Sports Physical Therapy. 2012 June; 42(6).


Diagnosing and Preventing 2,000,000 Ankle Sprains Per Year

by Dr. Bruce Buckman PT, DPT, ART

2,000,000. It’s a huge number. It’s also the estimated number of ankle sprains sustained every year in the United States alone. One in six injuries sustained by a high school athlete will be an ankle sprain, more specifically a lateral ankle sprain, making it the most commonly occurring injury in all high school sports. While most ankle sprains heal relatively quickly, 50% of the time they account for a loss of sport participation for more than one week. As always, it is important and necessary to understand ankle anatomy before learning prevention; but first, what are the risk factors for ankle sprains and how are they graded?

  1. Prior Injury
    • As with many injuries, prior injury is a significant risk factor for future ankle sprains, with 15.7% of all ankle sprains being that of a recurring injury in sport that involves jumping and landing.
  2. Braces
    • Think you are protecting yourself by wearing a brace? Think again! A 2013 study highlighted that athletes were wearing braces when 10.6% of ankle sprains occurred. Braces being worn included lace up, ridged frame, and neoprene sleeves.
  3. Contact
    • Play a contact sport? 42.4% of all ankle sprains occur as a result of contact with another player.

Grading Ankle Sprains

Grade I Sprain

  • Slight stretching and microscopic tearing of the ligamentous fibers
  • Mild tenderness and swelling around the ankle

Grade II Sprain

  • Partial ligament tearing
  • Moderate tenderness and swelling around the ankle
  • Abnormal looseness of the ankle joint

Grade III Sprain

  • Complete ligament tear
  • Significant tenderness and swelling around the ankle
  • Ankle instability

Fig. 1 Anatomy of the Ankle

Importance of an X-Ray

The Ottowa Ankle rules are well-established clinical guidelines used to determine the need for radiography (x-ray imagining). These rules are very good at ruling out the occurrence of an ankle fracture, if the following are not present. According to these rules, x-rays are indicated if there is pain in the malleolar zone and any of the following:

  1. Bone tenderness or pain to palpation of the distal 6 cm of lateral malleolus (Fig 1.)
  2. Bone tenderness or pain to palpation of the distal 6 cm of the posterior edge of the medial malleolus (Fig 1.)
  3. Inability to weight bear four steps immediately after the injury or in the ER

Bones and Ligaments

The ankle is composed of three structures: the Tibial malleolus, Fibular malleolus and Talus making up the “Mortise or Talocrural joint”. This is the principle joint of the ankle making up plantarflexion (toe pointing), and dorsiflexion (toes pulling up). With the SubTalar Joint the ankle also allows motions of Inversion (toes in), and Eversion (pinky toe pulling out). These motions are restricted by ligaments. The lateral, or outside, ligaments of the ankle joint include the Anterior TaloFibular Ligament (ATFL), which restricts inversion range of motion. It is also the most commonly injured ligament along with the CalcaneoFibular Ligament (CFL). The medial, or inside, ligament of the ankle joint is the very strong Deltoid Ligament Complex which restricts eversion range of motion. It is less often involved in ankle sprains due to its strength; however, can be affected in a traumatic inversion/ eversion ankle sprain.


The muscles of the ankle act to dynamically stabilize and protect the ankle joint to avoid injury to the ligaments mentioned above. Arguably, the most important muscles of the ankle that are involved in lateral ankle sprains are the Peroneus Longus and Peroneus Brevis. These two muscles originate at the fibula with the Peroneus Longus coursing around the posterior aspect of the lateral malleolus, underneath the foot, inserting into the first metatarsal (1st Toe). The Peroneus Brevis travels along the same path inserting into the styloid of the 5th toe. Together, these muscles stabilize the arch of the foot and act to prevent inversion range of motion.

The Anterior Tibialis muscle is another significant stabilizer of the ankle complex, originating from the lateral aspect of the tibia, and inserts into the top of the first metatarsal. Finally, the Gastrocnemius and soleus muscle originate at the backside of the tibia and fibula. Together, they insert into the Achilles tendon, which acts to plantarflex and inverts the ankle joint.

High Ankle Sprains

Fig. 2 Anatomy of the lower leg

High ankle sprains are different and typically more severe than a lateral “low” ankle sprain. High ankle sprains occur when the ankle is dorsiflexed, locking up the ankle joint, and forcefully planted on causing a twisting motion of the ankle. Due to the anatomy of the ankle, the syndesmosis (red arrow) is spread and occasionally torn. These ankle sprains involve the Tibiofibular joint’s syndesmosis (Fig. 2) and usually require increased healing time.

I know you are all wondering…

Does taping help? To sum up the research, the jury is still out on this question. Most research has found minimal evidence suggesting that ankle taping actually reduces susceptibility. Furthermore, research has actually found ankle taping to reduce proprioceptive feedback (the ability to understand where your ankle is in space) in an athlete who finds himself or herself in an unstable or abnormal position. Some research has supported the use of ankle taking by athletes who have experienced one or more ankle injuries, but it is important to understand that this should never be used as the first-line treatment for ankle injuries. Unfortunately, there is currently no recommended best practice guideline for this question.

Check out Part II in our video library for an explanation of 5 exercises to reduce the risk of ankle sprains. In conclusion, ankle bracing and or taping should not be used in place of aggressive physical therapy including strengthening, stabilization, muscle endurance training, and balance/proprioceptive training.


Swenson D, Collins C, Fields S, Comstock R.  Epidemiology of US High School Sports-Related Ligamentous Ankle Injuries, 2005/06-2010-11. Clin J Sport Med 2013;23(3):190-196.

McKay GD. Ankle injuries in basketball: injury rate and risk factors. Br. J. Sports Med.2001;35:103-108.

Preventing and Treating Injuries in Young Athletes

by Bruce Buckman, PT, DPT

Quadriceps (thigh) muscle strain, or avulsion fracture?

Approximately 60 million children ages 6-18 participate in some form of organized athletics, with 44 million participating in more than 1 sport. Greater numbers of participant in youth sports has led to more intense training and thus competition, which has increased susceptibility to over-use injuries. “Overuse injuries occur due to repetitive submaximal loading of the musculoskeletal system when rest is not adequate to allow for structural adaptation to take place”. These injuries may occur, but are not limited to muscle, tendons and bones. Further more, apophyseal injuries also almost exclusively occur in young athletes, especially those athletes who sports specialize (participate in intensive year-round training in a single sport at the exclusion of other sports).

So what now?

Seen below in blue, an apophysis is defined as a bony outgrowth or projection. This apophysis, the Anterior Inferior Illiac Spine (AIIS) of the pelvis, happens to be one of particular interest when considering injuries to youth athletes. Studies have demonstrated that soccer, track and field/running sports and baseball all pose an increased likelihood of injury, especially when considering the above paragraph.

So what is so special about the AIIS?

The AIIS is the origin of a muscle called the Rectus Femoris, which is located in the quadriceps muscle group. The rectus femoris aids in flexing the hip and extending the knee; conversely, this muscle is stretched with hip extension and knee flexion. Now, when eccentrically contracting (lengthening, or stretching, while simultaneously contracting) such as with a kicking motion, the rectus Femoris generates an extraordinary amount of force and pull on the AIIS, which in inadequately rested athletes may cause the AIIS to fracture.

Signs and symptoms

  • “Popping” to hip/groin region during injury
  • Point tenderness to AIIS/upper Rectus Femoris muscle
  • Bruising to upper thigh/groin
  • Pain with and without associated muscle weakness during hip flexion
  • Pain with walking and climbing stairs


  • Pelvic avulsions fractures are most often identified via X-ray imaging

Injury Reduction

  • Adequate rest time/muscle recovery in between sport/training activities
  • Foam Rolling Quadriceps musculature
  • Perform lower extremity dynamic warm- up including sport specific movement patterns such as in the FIFA 11+
  • Static stretching post activity

How Can Physical Therapy Benefit?

Studies have confirmed that non-surgical intervention can be effective in treatment of avulsion fractures at the hip with a mean return to play in 2.5 to 3 months. Most importantly, activity must be restricted initially in order to ensure proper tissue healing. Your physical therapist will assess all impairments and possible contributing factors in order to prescribe an individualized therapeutic exercise program including, strengthening (eccentric and concentric), stretching, balance/proprioception, and soft tissue mobilization. Manual therapy techniques may also include but are not limited to cross friction and soft tissue massage, tactile muscle cuing, and the addressing of associated impairment/restrictions that may predispose the athlete to injury. A home exercise program will be prescribed, as supplementation will improve healing time and patient tolerance to physical therapy appointments. It is also important to understand that once feeling better, with rest and treatment, your physical therapist will be in contact with your physical ensure to scheduling of follow up imaging studies to assess anatomical integrity prior to return to sport.

Need tips on Specific Injury Reduction techniques? Contact us at 201-746-6577 today to schedule an appointment with one of our physical therapists or chiropractors!


McKee, J. Conservative Treatment Effective for Most Apophyseal Fractures in Adolescents. American Academy of Orthopedic Surgeons. 2015: Volume 9 Number 8.